By H. Fedor. Murray State University. 2019.
A prospective survey of pediatric dermatology clinic patients in Kuwait: an analysis of 10 ,000 cases . Genome-wide scan for linkage reveals evidence of several susceptibility loci for alopecia areata . Neuropeptide control mechanisms in cutaneous biopsy: physiological mechanisms and clinical signicance . Efcacy and side effects including histologic study of the ensuing localized acneform response . Intralesional treatment of alopecia areata with triamcinolone acetonide by jet injector . Systemic steroids with or without 2% topical minoxidil in the treatment of alopecia areata . High-dose pulse corticosteroid therapy in the treatment of severe alopecia areata . Pulse methylprednisolone therapy for severe alopecia areata: an open prospective study of 45 patients . Topical photodynamic therapy with 5- aminolaevulinic acid does not induce hair growth in patients with extensive alopecia areata . Etanercept does not effectively treat moderate to severe alopecia areata: an open-label study. Alopecia areata in a patient using iniximab: new insights into the role of tumor necrosis factor on human hair follicles. The use of methotrexate alone or in combination with low doses of oral corticosteroids in the treatment of alopecia totalis or universalis. Pilot study to evaluate the effect of topical betamethasone dipropionate on the percutaneous absorption of minoxidil from 5% topical solution. Topical nitrogen mustard in the treatment of alopecia areata: a bilateral comparison study. Systemic cyclosporine and low-dose prednisone in the treatment of chronic severe alopecia areata: a clinical and immunopathologic evaluation. Comparison of azelaic acid and anthralin for the therapy of patchy alopecia areata: a pilot study. Alopecia totalis in a patient with Crohns disease and its treatment with azathioprine. The potential efcacy of thalidomide in the treatment of recalcitrant alopecia areata. Glatiramer acetate in multiple sclerosis: update on potential mechanisms of action. Immunohistologic and ultrastructural comparison of the dermal papilla and hair follicle bulb from active and normal areas of alopecia areata. Efcacy and safety results of a clinical study of efalizumab in patients with alopecia areata. It affects both sexes and all ethnic groups although the severity and frequency are greater in men and there are racial differences in prevalence. Male androgenetic alopecia is a trait rather than a disease, pre- dominantly determined by genetic factors. However, female androgenetic alopecia may also be a manifestation of signicant androgen excess due to an underlying endocrine disorder. The pathology appears identical in men and women although the pattern of hair loss tends to differ between the sexes and there is some controversy over whether male and female androgenetic alopecia share the same etiology. Very few people enjoy losing their hair and it is probably true that a simple, cheap, non- toxic and effective one-off treatment would be widely taken up. Until this ideal is realized many men, though not all, are content to accept their lot. This is rather less true of women, in whom loss of hair has a greater adverse effect on quality of life. In this article the treatments currently available for androgenetic alopecia are reviewed, together with a brief consideration of the etiology and epidemiology. In the majority of men balding is pat- terned, in which the two major components are fronto-temporal recession and loss of hair over the vertex. Ulti- mately this may lead to complete hair loss except at the lateral and posterior margins of the scalp where hair is retained. Hamilton clas- sied male balding into several stages (1) and the revision of his classication by Norwood is still widely used (2). There is sometimes a history of excessive hair shedding, which may predate a clinically obvious reduction in hair density. Examination of the scalp shows a widening of the central parting with a diffuse reduction in hair density mainly affecting the frontal scalp and crown. In some women the hair loss may affect a quite small area of the frontal scalp whereas in others the entire scalp is involved, including the parietal and occipital regions. Some women have more pronounced temporal recession although this usually manifests as thinning rather than the complete loss of temporal hair as seen in men. The latent phase, also termed kenogen, refers to the interval between shedding of the telogen hair and reentry into anagen. This has been demonstrated in aging male scalp hair follicles (7) and there is some evidence that it also occurs in women (8). There is little evidence that medical treatments are able to reverse follicular miniaturization; it follows, there- fore, that preservation of terminal hair density is best achieved by treatment at an early stage in the development of hair loss. A modest degree of chronic inammation around the upper part of hair follicles, sometimes associated with perifollicular brosis, is a common feature of the histopathology (4,9). The American anatomist James Hamilton observed that men castrated before puberty do not go bald unless treated with testoster- one (10). There are two isoforms of 5-reductase that are encoded by different genes (11,12). Type 1 5-reductase is widely distributed in the skin (13), but expression of the type 2 isoform is limited to certain andro- gen target tissues such as the prostate, the epididymis, and hair follicles in certain regions of the skin. These observations were extended by the demonstration that treatment with a 5-reductase inhibitor prevented the development of balding (15) or increased scalp hair growth (16) in macaques, a primate that reliably develops androgen-dependent hair loss. This latter nding also shows that, contrary to Hamilton s conclusions from his observations in eunuchs, male balding is partially reversible. Nevertheless, other factors are clearly involved as not all men develop balding despite similar androgen lev- els to those that do. The role of androgens in female androgenetic alopecia is less clear-cut than it is in men. Scalp hair loss is undoubtedly a feature of hyperandrogenism in women (although it is much less frequent than hirsutism). Indeed, loss of hair was reported in women with andro- gen-secreting tumors prior to Hamilton s observations in men (18,19). Several investigators have noted that women with hair loss are more likely to have elevated androgen levels or show an increased frequency of other features of androgen excess than women without hair loss. In a recent series of 89 women presenting to a trichology clinic with hair loss, 67% showed ultra- sound evidence of polycystic ovaries compared to 27% in a control group of 73 women, and 21% were signicantly hirsute compared to 4% of controls (22). The results of clinical trials of anti-androgens have also questioned whether female androgenetic alopecia is necessarily androgen-dependent and consequently the less committal term female pattern hair loss is preferred by some clinicians. Genetics Twin studies have demonstrated that the predisposition to male balding is predominantly due to genetic factors (24 26). Published concordance rates for monozygotic twins are around 80 90%, with consistently lower rates in dyzogotic twins. Several studies have shown there is a high frequency of balding in the fathers of bald men. So far, attempts to identify the relevant genes have been limited to a small number of candidate gene studies. No associations have been found with 5-reductase genes (27,30) or the insulin gene (31). This nding therefore conrms there is a mater- nal inuence on male balding but does not explain the genetic contribution from the father. Prevalence Population frequency and severity of androgenetic alopecia in both sexes increase with age. Almost all Caucasian men develop some recession of the frontal hairline at the temples during their teens. Deep frontal recession and/or vertex balding may also start shortly after puberty although in most men the onset is later. A small proportion of men (15 20%) do not show balding, apart from post-puber- tal temporal recession, even in old age. Some authorities have suggested that scalp hair loss in elderly men may develop independently of androgens (senescent alopecia) but this remains to be veried (35). Balding is less common in Asian men although there is quite a wide variation in pub- lished frequencies. Two recent studies from Thailand and Singapore found prevalence rates not far short of those in Caucasian men (36,37). In Korean men the frequency is 20 40% lower than in Caucasian men in the 40 70 age group although the difference becomes less pro- nounced with advancing age (39). Preservation of the frontal hairline was a common feature in the series reported from Korea and 11. One early study reported that balding is four times less common in African- American men than in Caucasians (40). The frequency and severity of androgenetic alopecia is lower in women than in men but it still affects a sizeable proportion of the population. Two studies in Caucasian women in the United Kingdom and the United States reported prevalence rates of 3 6% in women aged under 30, increasing to 29 42% in women aged 70 and over (41,42). As in men, androgenetic alopecia is less common and appears to start later in life in Asian women, although nearly 25% of Korean women over 70 years of age show evidence of hair loss (39). There are no published data on the prevalence of androgenetic alopecia in African women although clinical experience suggests that its frequency is similar to that in other racial groups. Under normal circumstances it has no adverse effect on physical well-being apart from increasing the risk of chronic photodamage to unpro- tected scalp skin. Under exceptional conditions a full head of hair may also contribute to ther- moregulation. The French military surgeon Dominique-Jean Larrey observed that the bald men (and men without hats) were the rst to die during the Russian campaign in the winter of 1812. Yet balding still has a powerful effect on the human psyche, to the extent that few men would choose to go bald were the choice available. However, for some men balding is important enough for them to seek treatment and, for a few, concern about hair loss reaches the level of a body dysmorphic disorder. Men in the latter group are important to recognize as treatment aimed at addressing the perceived hair problem is unlikely to be successful. A number of studies have shown that male balding has an adverse effect on quality of life (though this is almost inevitable in those seeking professional advice) (43). Nevertheless, balding is often seen as a trivial issue (mainly by non-sufferers) which may make men reluctant to approach their physician as they perceive, rightly or wrongly, that they will not receive a sympathetic response. In contrast to the pre- vailing attitude to male balding, however, society generally regards it as abnormal for women to lose their hair. Consequently the adverse effect of balding on quality of life tends be more severe in women than in men. In quality-of-life studies, individual responses were more related to self-percep- tion of hair loss than to objective or clinical ratings and those women most distressed by hair loss were more poorly adjusted and had a greater investment in their appearance (44,45). The physician needs to be alert and sensitive to these issues and needs counseling and psychothera- peutic skills that go beyond merely prescribing treatment. Diagnosis The diagnosis of androgenetic alopecia in men rarely causes difculties. In cases presenting with general thinning, other causes of diffuse hair loss should be considered, particularly when the hair loss progresses quickly. This situation is perhaps most likely to be seen in teenage boys brought along by worried parents. The diagnosis of female androgenetic alopecia may be more challenging although it can usually be made on clinical grounds. Rapidly progressive hair loss with a strongly positive tug test should raise the possibility of diffuse alopecia areata. Loss of body hair, eyebrows, or eyelashes, and nail changes will support the diagnosis but it is sometimes necessary to obtain histology. Other causes of diffuse hair loss include systemic lupus erythematosus and thyroid disease and the relevant investigations should be performed where indicated by the overall clinical picture. Occasionally, scarring alopecia presents in a diffuse pattern and here a biopsy will usually be necessary. The most common clinical dilemma is the diagnosis of women pre- senting with chronic excessive hair shedding in whom hair density appears normal, often referred to as chronic telogen efuvium. If known causes of telogen efuvium are excluded, about 60% of these women show histological evidence of early androgenetic alopecia on biopsy (46). The cause of increased hair shedding in the remaining 40% is usually obscure, although it may simply be due to age-related shortening of the hair cycle. It should also be remembered that androgenetic alopecia may be a sign of hyperandrogen- ism. Investigations are unnecessary in women with typical androgenetic alopecia and no other evidence of androgen excess, although most authorities recommend checking a full blood count, serum ferritin and thyroid function. In the author s experience, abnormalities of thyroid func- tion are not particularly common in women presenting with diffuse hair loss, possibly no more Androgenetic Alopecia 111 common than in the population at large, but formal data are lacking. The most important cause, albeit rare, is an androgen-secreting ovarian or adrenal tumor. A serum testosterone is a useful screening test; a level in excess of 5nmol/l should prompt further endocrinologic investigation.
The degree of damage to infected glands tion of further new intramammary infection . Swelling of the infected quarter usually is sufcient for detection , treatment , and control . Fever and inappetence may accompany correction of milking machine problems , postmilking acute infection . Cattle that are closely observed may have teat dipping with iodine teat dips , and dry cow therapy a less severe and gradual inammation of the infected are very effective in the control of coagulase-negative gland . Obvious causes of teat skin irritation vanced when nally recognized and represent fulminant should be eliminated . Wet milking or poor udder prepa- abscessation of a longer-standing , subacute or chronic ration are notorious problems in producing high num- infection. Cows having truly acute infections are febrile bers of coagulase-negative staphylococci in bulk tank milk and have rm inamed quarters and watery secretion and a high incidence of mastitis resulting from these with thick clots or ricelike clumps in the secretion. Abscesses may appear in a high percentage of intramammary infection as a result chronic cases and are located anywhere in the gland. Most chronically dine teat dips have been reported to be superior to other infected glands are ruined by the infection. Notice that the cow has been kept in a lthy environment as evidenced by dried mud on the udder and rear legs. Although protective against introduction of some mastitis or mastitis caused by some other primary patho- mastitis pathogens, dry cow formulations would be inef- gen. Cure rates have been so low histori- of necrotic or compromised mammary tissue from pyo- cally for A. Diagnosis is conrmed by culture of se- ter or chemically sterilize it using solutions containing cretion from the quarter. Although the prognosis is guarded, early attempted dry off or chemical sterilization meets with recognition of A. Before intra- disease, namely, abscessation and spontaneous drainage mammary administration of antimicrobials, infected from the skin of the affected quarter. The lactose-fermenting gram-negative rods Penicillin should be infused into the quarter once or such as E. Most cattle that improve require 7 to 14 days tis is familiar to all bovine veterinarians because of the of antibiotic therapy. Cattle that do not improve eventu- mortality associated with the infection in dairy cattle ally develop draining udder abscesses and cease lactating and because farmers call on veterinarians to treat coliform in the infected quarters. Other signs of Coliform mastitis also is the subject of heated debate re- improvement include reduced size of the gland and a garding proper therapeutics, drug residues, and drug with- more uid secretion. Deep mud in barnyards greatly in- the postpartum period, such as hepatic lipidosis or re- creases the likelihood of coliform organisms contami- tained placenta, may depress neutrophil function and al- nating the udder. Neutrophils may respond to multiplication and persistence of coliforms in the to infection of the gland at a slower rate in recently fresh environment such that the incidence of coliform masti- cows than in those in mid-lactation. Dry cows exposed to heavy numbers of environmen- However, because of the widespread use of free stall tal coliforms may become inapparently infected until housing for cattle, the damp barn environment present the periparturient period. Indeed, rates of new intramam- in free stalls predisposes to coliform mastitis, regardless mary infections caused by coliforms are greater during of seasonality. Dry cows are at fetal membranes may also increase the risk of coliform greatest risk for infection just after drying off and just infection. Epidemics of seen in herds in which contagious causes of mastitis Klebsiella mastitis have been associated with the use of have been controlled. High coliform/g of bedding increases the risk of coliform mas- concentrations of intramammary neutrophils have been titis. Kiln-dried sawdust may be better but is harder, and shown to deter coliform mastitis via the rapid engulf- more expensive, to obtain. Milking be a better choice than sawdust, and inorganic bedding procedures and teat-end injuries are important contrib- materials such as sand and crushed limestone will re- uting factors to coliform mastitis. In some herds with a duce the environmental exposure to coliform bacteria low level of contagious mastitis, coliforms are not only still further. In terms of both cow health and comfort, the most common cause of clinical mastitis but also may sand should be viewed as a preferable bedding material be the most common organism cultured from the milk for free stall housing. An advantage of sand is that it is Poor udder sanitation before milking is an obvious pushed out of the free stall bed by the cows more slowly problem. However, if beds are not picked and milking or use of contaminated wash water for udder scraped free of manure daily, coliform counts will quickly disinfection contributes to outbreaks of coliform masti- increase. Mechanical or procedural milking problems such as economic option for larger free stall dairies that use this vacuum uctuations leading to squawking or drop off bedding material. It appears that properly recycled sand can reverse milk ows at the teat end that inject coli- does not carry forward high-risk gram-negative bacterial form-contaminated milk droplets into the teat end and populations in bedding, although persistence of envi- streak canal. These injuries also cause counts experience the highest incidence of clinical masti- pain, which leads to incomplete milkout, and a tendency tis within the rst 30 days of lactation. Udder edema, in- to leak milk between milkings and a predisposition to- complete milkout, hemorrhage into the gland, sprinkling ward coliform infection. The bacteria are destroyed by phagocytosis and pathogens to enter the teat cistern and gland. However, in the course metabolic diseases such as hypocalcemia that cause the of bacterial lysis, the release of endotoxin initiates a cas- cow to remain recumbent also may increase the exposure cade of inammatory mediators, which in turn leads to to environmental coliforms. Inammatory mediators including histamine, se- rotonin, and eicosanoids are activated or are released during the process. Oxygen free radicals probably are produced during acute coliform infections because studies have shown a reduced incidence of severity of coliform mastitis in herds that have adequate vitamin E and selenium levels. Endotoxins cause rumen stasis and ileus and delay calcium absorp- tion from the gut. In addition, the inappetence reduces calcium intake in the face of continued calcium drain from lactation. Hypokalemia can be a major contributing cause to weakness or recumbency in cows with coliform mastitis. The electrolyte disturbance is thought to occur by a combination of decreased potassium consumption, de- creased potassium absorption from the gut, and ileus- related metabolic alkalosis. Clinical signs associated with coliform mastitis probably become apparent after bacterial levels have peaked and the inammatory cas- cade is maturing. On post- plain the inability of clinicians to isolate coliforms from mortem examination the gland had infarction. Delaying collection of milk for culture or previous treatment further contributes to negative cultures. Freezing of milk samples may in- not only because of lipopolysaccharide (endotoxin) crease the sensitivity of bacteriologic culturing by releas- and its effects but also from deep infection of the gland. The cover spontaneously and certainly do not have sterile role of host (cow) factors in deciding whether a cow will quarters. Affected quarters are the inoculum plays a role, and therefore the level of envi- warm and swollen. The degree of rmness varies, with ronmental contamination on the farm is an important some cows having only doughy or edematous quarters, control point, but the metabolic and immunologic status whereas others are very rm. Peracute inammation of the transition cow are very important factors in decid- may cause subtle swelling of the quarter in some peripar- ing the prevalence and severity of new, coliform intra- turient cows that may mask the inammation-related mammary infections in dairy cattle. Regardless of the degree of swelling, the secre- Chronic cases of coliform mastitis once were thought tion in coliform mastitis (acute) is more watery than that to be rare but now have been routinely conrmed in at in unaffected quarters. Chronically infected as serum-like or watery by most experienced clini- quarters may be nonproductive or may have subclinical cians and is best detected by rst stripping normal mastitis with intermittent areups that mimic other milk from an unaffected quarter onto a black-colored causes of acute mastitis. Unfortunately spontaneous plate, then milking secretions from the affected quarter cure is difcult for the cow that has been chronically onto the normal milk. Rectal temperatures ranging sociated with coliform mastitis predispose affected cows between 104. Patients that tant recumbent periparturient hypocalcemia may be have been treated with high doses of dexamethasone hypothermic rather than febrile. Some affected Rarely cattle with peracute coliform mastitis have cows will shiver and have their hair stand on end as developed lactic acid indigestion following ingestion of early nonspecic signs that are associated with fever and large meals of high-moisture corn. Ophthalmic consequences of the toxemia profound rumen stasis from endotoxemia was thought associated with coliform mastitis may include scleral in- to contribute to malfermentation of the grain. Cows may be- The severity of endotoxic signs varies tremendously in come recumbent from the profound weakness resulting cattle with coliform mastitis. Many cattle affected with acute nosis and may interfere with detection of the mastitis. The coliform mastitis that subsequently was conrmed as udders of all recumbent cattle, especially those in the early resulting from Klebsiella sp. The importance of careful examination of the milk with a black strip plate cannot be overemphasized. Plates should be examined under reected lighting to detect subtle changes that may occur early during coli- form mastitis. Tests based on increased milk pH are used for the detection of coliform mastitis in Europe, but such tests are less available in the United States. Freezing and thawing the samples before inoculation onto media increases the sensitivity of the test but could also kill some sensitive bacteria. Treatment of coliform mastitis has been The individual was recumbent, severely dehydrated, and controversial because of the administration of extra-label acidemic. Many experimental studies acids are better choices for intramammary administration of coliform mastitis emphasize that infection resolves for the treatment of clinical mastitis, whereas the weak spontaneously as a result of the inammatory neutro- bases achieve better tissue levels when given systemically. Penicillin and ampicillin, weak acids, high mortality rate from coliform mastitis. It is impossi- attain limited ratios in the milk of a healthy cow follow- ble, clinically, to distinguish signs that are associated with ing parenteral administration. Systemic ceftiofur and the persistent infection from those of persistent endotoxemia, aminoglycosides have the poorest distribution in mastitis and furthermore continued signs of endotoxemia may patients. Even knowing Results of studies examining experimental and natu- about these studies, the practicing veterinarian may not ral coliform mastitis treatments are highly confusing. In wish to withhold antibiotic therapy when faced with a one eld study, no apparent benet resulted when sys- greatly distressed or litigious owner whose valuable cow temic gentamicin was used in the treatment of coliform becomes gravely ill with coliform mastitis. The reported success in cows treated systemi- majority of experimental studies demonstrate that antibi- cally with gentamicin (to which the organisms were otic therapy confers no benet on induced coliform mas- sensitive) was no better than in cows treated systemi- titis, there are a smaller number of studies that do show cally with erythromycin, even though the causative or- favorable outcomes when severe eld cases are treated ganisms were resistant to erythromycin, or in nontreated with antibiotics such as ceftiofur. All quarters in this study were treated with with the repeated demonstration of true bacteremia in a cephalothin, regardless of the systemic antibiotic cho- proportion of cows with naturally occurring coliform sen. This differs from another study that demonstrated mastitis, are strong arguments in favor of systemic antibi- a benecial effect of ceftiofur treatment in cows with otic administration. It is no wonder that most prac- apy, albeit controversial, should be understood by bovine titioners develop an individual or clinic-based approach practitioners. The pharmacology and likely benets or to the therapy of coliform mastitis in the eld based on risks associated with each antibiotic should be known their own experiences. Currently approved anti- portant that treatment decisions are made within the biotics for use in lactating cattle are listed in Table 8-1. Although the likeli- Studies that report antibiotic susceptibility of gram- hood of sensitivity of the organism to oxytetracycline is negative bacteria causing mastitis have been reported, only moderate, distribution of the drug to the udder and the accumulated data from these studies and re- should be good, and the drug may provide some antiin- views combined with more recent culture and antibiotic ammatory properties within the udder. Nephrotoxic sensitivity results indicate the following: effects may occur in dehydrated cows treated with oxytet- 1. It is impossible to recommend one treatment sporins, and ticarcillin-clavulanic acid work against because of geographic differences in bacterial popula- most coliforms in vitro tions, resistance patterns of coliform organisms present 2. Polymyxin B and cephalothin work against 60% to on each farm, and many other factors. Culture and sensi- 80% in vitro tivity results should be obtained for isolates from each 3. Tetracycline, ampicillin, neomycin, and kanamycin farm to better determine appropriate antibiotic therapy work against 40% to 80% in vitro when faced with an acute coliform mastitis. Inammation and serum leakage into the gland in- New antibiotics such as orfenicol, a derivative of crease the pH of the milk to nearly physiologic levels chloramphenicol that is not associated with aplastic ane- (7. Inammation, cellular debris, and experimental drugs that have been shown to have good decreased ability to diffuse drugs throughout the quarter distribution via systemic and intramammary routes for diminish the effectiveness of antibiotics especially intra- bovine mastitis. Although most farms harbor a multitude of coli- cial effect on the survival rate of endotoxemic cattle. Flor- forms, culture and antibiotic sensitivity results from fenicol is also not approved for lactation-age dairy cows. Historically stripping every 1 or 2 hours has been advocated, but that has now been refuted with respect to outcome, and cur- rent guidelines call for stripping no more than every 4 to 6 hours even in peracute cases. Too frequent stripping may cause the teat sphincter to remain open, allowing other organisms to gain entrance. Alternatively, one or more calves may be placed in a box stall with the affected cow to nurse the quarters frequently. Obviously, individually as to present and future productive and ge- however, in clinical practice, their use is never prophylac- netic value before a decision to treat with antibiotics is tic because clinical signs only appear after endotoxemia made. Abomasal ulceration is the most frequent gastro- live or die on the farm and salvage for meat is not an op- intestinal complication of overdosage, prolonged use, or tion. If the cow s life is in jeopardy and extra-label drugs employment of these drugs (especially unixin meglu- or dosages are deemed necessary to save the cow, the mine) in very dehydrated patients. Renal papillary ne- owner and practitioner are responsible for ensuring ade- crosis and renal infarcts may develop in cattle treated quate withdrawal time. Some clinicians use intramammary cortico- many cases of coliform mastitis are life-threatening, the steroids such as 10 to 20 mg of dexamethasone as a destruction of glandular tissue is generally less than what one-time treatment. Other clinicians administer 10 to occurs with gram-positive infections, and if the cow sur- 40 mg of dexamethasone systemically. Although corti- vives and quickly clears the infection (with or without costeroids may alleviate the inammatory cascade, they antibiotics), return to near maximum production may be present risk of chronic infection and deter defense possible in the next lactation.
These two isolates could be considered as good candidates for further use as biopesticide taking into account their virulence and thermotolerance . Other critical factors linked with the implementation of this type of biocontrol in P . Keywords Psoroptes ovis Biological control Entomopathogenic fungi Temperature Virulence M . Nevertheless treatment failures and environmental consid- erations have led to the development of alternative approaches , particularly the use of entomopathogenic fungi (Smith et al . Because infection by entomopathogenic fungi such as Beauveria and Metarhizium species results from direct penetration of the tegument without any requirement for ingestion , these organisms often display wide host ranges . There is a growing literature dealing with their virulence and use in insects , ticks and other members of the class Arachnida (Kaaya and Munyinyi 1995; Chandler et al . Additionally inter- and intraspecic differences in the pathogenicity were observed in different arthropod species (Ferron and Diomande 1969; Daoust and Roberts 1982; Barson et al . To abate the development of psoroptic mange, 50% of the mite population must be killed every 2 days (Wall et al. These two factors were unfortunately not achieved with the isolates 8 -1 evaluated by these authors at a concentration of 10 conidia ml. It seemed thus inter- esting to test various isolates belonging to different genera and species in order to identify a highly virulent one. Moreover the high temperature prevailing at the skin surface of the hosts could limit the use of these fungi for the control of P. Indeed the temperature at the skin level varies between 31 and 37 C in sheep, and between 30 and 35 C in cattle (Brooks et al. However, differences can be observed between isolates with respect to thermotolerance. The aim of the present study was thus to investigate in twelve entomopathogenic fungal isolates the in vitro pathogenicity against P. These isolates belonged to four genera and originated from temperate and tropical areas. Materials and methods Mites Psoroptes mites were isolated from the ears of chronically infested rabbits maintained at the laboratory of the Faculty of Veterinary Medicine, Liege,` Belgium. Adult females were collected from freshly removed scabs (maximum 1 h) and directly transferred into conidial or control suspensions. The conidial suspension was pipetted from the plate and the con- 8 6 centration was evaluated using a haemocytometer. The handling chambers were sealed with paralm and placed at 27 C in an incubator exposed to the articial illumination of the lab during working periods. Mites were examined daily and dead mites (absence of motility) were transferred, after washing in 0. This plate was left at 27 C and checked every day for the apparition of fungal hyphae on the mite body. Entomopathogenic activity of the fungi was conrmed by examining histological sections of infected cadavers. Although the data were not distributed normally (with or without transforma- tion), the effects observed were so highly signicant (P 0. Only four isolates were able to infect 100% of the mites at all concentra- tions: M. Four isolates were able to infect 100% of the mites at 10 and 7 -1 10 conidia ml : B. Histological sections conrmed the presence of fungal hyphae inside the body of the infected mites. The interaction between isolates and temperature was also signicant with a nearly perfect suitability with the 2 model (r = 0. The analysis of the results showed that the temperature proles of temperate and tropical strains of B. For the other isolates, no comparison could be made but it is noteworthy that also the temperate isolate P. Discussion The use of entomopathogenic fungi for the control of psoroptic mange was rst evaluated by Smith et al. The major advantage of the fungal pathogens is that they infect their hosts directly through the tegument. Psoroptes ovis is almost completely unsclerotised which facilitates the penetration of the hyphae. Until now, only two species of entomo- pathogenic fungi have shown lethal activity against this mite, i. The rst one is the rate of killing the target (50% of dead mites every 2 days, according to Wall et al. This study demonstrated that several other species of entomopathogenic fungi have a lethal activity against Psoroptes mites. Additionally a 100% 6 -1 infection rate was also recorded at a concentration of 10 conidia ml. Therefore the entomopathogenic fungi could spread very easily on the host and in the herd. Indeed movements of the infected arthropods are the most efcient way of dispersion for the entomopathogenic fungi such as M. This way of infection has an additional advantage as it allows the use of a lower concentration of conidia and, consequently, easier and cheaper mass production. The infection process was not really submitted to a dened photoperiod; nevertheless the dishes received the articial light of the lab during the working periods. Some authors showed indeed that virulence, germination or conidial production on cadavers could be affected or not, depending on the fungal species by the applied photoperiod (Tang and Hou 2001; Hiroki et al. In the present study the germination of the fungi tested did not show any alteration when incubated in the dark. However, isolates with an optimal growth under these conditions may not be suitable for application on cattle skin where the temperature is higher (30 35 C) as shown by Polar et al. Consequently the isolates were tested for their growth on articial medium at temperatures ranging from 25 to 37. It appeared that all strains were capable of growth up to 30 C and all but one (B. These results are in agreement with other studies (Hallsworth and Magan 1999; Davidson et al. However it is noteworthy that only one tropical strain was included in the present study. These differences could be explained by the hosts from which the fungi originated. In fact, isolates originating from acridids were generally more heat tolerant because the temperatures can reach 47. However several of the isolates used in this study were isolated from the soil and it is not possible to draw any conclusion. In addition, the skin temperature on cattle uctuates during the day (Polar et al. Fortunately, these authors demonstrated that isolates which are more thermotolerant are more likely to exhibit high level of pathogenicity under conditions reecting the thermal characteristics of the cattle coat. Thus the next step should consist of an in vivo bioassay to verify that the isolates able to grow in vitro at temperatures ranging from 30 to 35 C are able to germinate, infect the mites and sporulate on the body surface of cattle in presence of diurnal temperature uctuations. A saprophytic microora can in fact be present on the tegument of the arthropods or on the hair of the host and stimulate or suppress the germination of the conidia in vivo (Schabel 1978; Fargues 1981; Polar et al. High relative humidity is generally con- sidered to be necessary for conidial germination but contradictory data can be found concerning this parameter (Lord 2005). In the case of cattle psoroptic mange, the relative humidity at the skin surface is high. Furthermore, it is likely that the conidia formulation would play a crucial role in the infection process by maintaining a high humidity level 102 J. In the case the conidia would still be present when the cows are turned out, the solar radi- ations could inactivate them which could prelude the dissemination of the fungus to non- target organisms. From the present study, two isolates could be considered as potential control agents for psoroptic mange: M. Because of the availability of mass production procedures for the former (no commercial biopesticide based on the use of P. Acknowledgements This study was supported by the convention S-6145 from the Ministere` de la Sante, Belgium. Ann N Y Acad Sci 916:172 178 Samish M, Gindin G, Alekseev E, Glazer I (2001) Pathogenicity of entomopathogenic fungi to different developmental stages of Rhipicephalus sanguineus (Acari: Ixodidae). Meikle Guy Mercadier Niels Holst Vincent Girod Originally published in the journal Experimental and Applied Acarology, Volume 46, Nos 1 4, 105 117. Objectives were to evaluate treatment effect on colony weight, adult bee mass, capped brood, and on Varroa fall onto sticky boards. Treatments included conidia for- mulated with either carnauba or candelilla wax powder, candelilla wax powder alone, or control; in two treatment groups formulation was applied a second time after one week. Colonies treated twice with Bb05002 conidia and carnauba wax powder had signicantly higher mite fall compared to colonies treated with blank candelilla wax powder. The proportion of fallen mites that were infected in both conidia treatments was higher than controls for 18 days after the second treatment. The number of fungal propagules on the bees themselves remained elevated for about 14 days after the second treatment. These results were compared to published results from previous experiments with regard to infection duration. Keywords Apis mellifera Varroa destructor Beauveria bassiana Biopesticide Formulation W. Varroa infestations have been largely responsible for the almost complete elimination of feral colonies in the U. The use of entomopathogenic fungi has been considered a promising alter- native to chemical miticides (Chandler et al. Collecting fungal isolates from either the target environment and/or even the target pests themselves is intended to increase the probability of nding the best adapted isolates. The high temperatures and humidities of beehives, among other factors, can present similar challenges to entomo- pathogenic fungi. Beauveria bassiana is known to have a broad host range (Tanada and Kaya 1993) and Meikle et al. Formulation with carnauba wax has been tested in previous studies and no negative effects have been observed with respect to honeybee colony health (Meikle et al. Treating hives with a powder, such as powdered sugar or pollen, is known to provoke mite fall (Fakhimzadeh 2001; Macedo et al. Diseases of Mites and Ticks 107 The main objective in this study was to evaluate the impact of two successive appli- cations of conidia of entomopathogenic fungi on colony health and on Varroa mite fall. Two kinds of wax powder were also compared as formulation ingredients: car- nauba wax, as used in previous experiments, and candelilla wax, which is obtained from Euphorbia antisyphilitica and Pedilanthus pavonis and is also safe as a human food ingredient (U. Here we measured colony growth rates per week, total adult bee weight and the amounts of sealed brood and honey. The use of growth rates, which are independent of colony size, was intended to facilitate comparison of these results with other studies. Varroa mite fall and the proportion infected mites were measured as in Meikle et al. Conidia were har- vested by scraping the surface of the cultures onto glass petri dishes with a metal spatula, and placing the petri dishes in a crystallizing dish containing silica gel for 20 24 h at room temperature for drying. Since carnauba wax powder alone had been tested in previous experiments (see Meikle et al. The density of colony-forming units (cfu) per g formulation was determined at the time of colony treatment by plating three sub-samples of the formulation diluted in distilled water and Tween 80 (Merck, Munich, Germany) onto potato-dextrose agar, and counting the number of colonies 96 h after plating. Field experiment In April 2007, 26 honeybee colonies were selected for the eld experiment. The colonies were part of an apiary of 52 colonies near Lattes, in southern France. The bee colonies were kept in painted, 10-frame, wooden Langstroth brood boxes (56 l capacity) with telescoping lids and with screens underneath the frames and queen excluders on top of the 108 J. The boards were replaced on 24 April and every 3 4 days thereafter with fresh boards. All mites adhering to the used boards were counted, and 40-mite samples were taken from each board and plated on water agar (6. Plated mite samples were incubated at 23 C, examined for sporulation after 15 days, and the proportion of sporulating cadavers was calculated (hereafter referred to as the proportion infected mites ). The hive was then reassembled, and one super containing nine frames with wax foundation was weighed and placed on top of each colony. Five colonies were selected for each treatment group except the untreated control, which had 6. Colonies were randomly assigned treatments, but treatments were occa- sionally re-assigned to distribute treatments evenly. To calculate colony and adult bee weight, hive weight was divided into a non-colony part, consisting of the hive pieces, e. Adult bee weight was calculated as the difference between the sum of the weights of all the hive parts and the observed hive weight. The non-colony weight was calculated as the total weight of all the hive parts except brood box frames, plus the weight of 10 empty frames, or about 2. Colony weight was calculated by subtracting the non-colony component from the total hive weight. The area of sealed brood and sealed honey per frame was estimated from the photographs using ArcView 3. Two subsamples of ve bees each were removed from bags of three colonies per treatment (the same colonies were always used) for a total of 30 subsamples.
Additionally , the equations for estimating lean mass may not be appropriate when patients are wasted or water balance is abnormal . Accuracy decreases when scanning either very small infants or very large individuals such as obese adults (8) . Patients who are edematous often complain of swelling of the hands and feet , making rings and shoes tight . If the area is pressed and leaves a dent for 5 seconds or more , edema is likely to be present . Care should be taken when evaluating a biochemical test to consider the disease , whether a fasting state is required , whether there are diurinal variations , and medication or supplement intakes that may influence the laboratory results. For example, a low ferritin value is not only an indication of potential iron deficiency, but may also be low because of protein calorie malnutrition. For example, serum albumin is often decreased because of inflammation and wasting rather than low dietary intake of protein. Serum Proteins Visceral proteins are proteins synthesized in the liver that circulate in plasma (12). These visceral proteins are also acute- or negative-phase proteins and change according to stress and inflammation. They include urinary creatinine, serum creatinine, and urinary 3- methylhistidine. These indices are sometimes used to assess protein and muscle status, but they are rather nonspecific (12,13). Many of the acute- and negative-phase reactants are used to assess the short-term visceral protein status in individuals. This section focuses on albumin and transthyretin because they are the most common biomarkers for protein used in clinical practice. Serum albumin is commonly used in clinical settings to assess protein status in individuals, although it is of only limited utility because it is affected by many other factors, including the presence of inflammation. Although it is true that serum albumin decreases with protein restriction, it changes little with energy restriction (12). It has a relatively long half-life of about 20 days and it changes only slowly (12). Low levels of serum albumin are associated with liver disease, pregnancy, increased capillary permeability, and overhydration. Transthyretin is a transport protein that binds with thyroxin and retinol-binding protein (12). It is another negative acute-phase reactant, and decreases in response to stress and infection, but it is also altered by zinc status (12). The advantages to using transthyretin are its short half-life, which is about 2 days (12,13), making it more sensitive to changes. However, it also has all of the disadvantages that have been described for serum albumin, including lack of specificity and high cost (12). Creatinine is found primarily in the muscles and is sometimes used as an indicator of muscle mass and adequate energy status. Serum creatinine is 22 Part I / Introduction to Rheumatic Diseases and Related Topics affected by disease and diet. A high consumption of muscle meats that contain creatine in the diet may give rise to high serum creatinine. A complete 24-hour urine collection is best, but collecting 24-hour urine samples may be difficult for ambulatory patients. The skeletal muscle mass (in kilograms) is sometimes very roughly estimated with this equation: the 24-hour urinary creatinine (grams per day) is multiplied by 18. Urinary creatinine levels are increased with exercise and with high meat intake (13). Urinary 3-methylhistidine is found only in muscle and is associated with muscle mass. A complete 24-hour urine 3-methylhistidine collection is required to obtain estimates of muscle mass. Calcium Serum calcium levels may be measured using total calcium or ionized calcium tests, but both are tightly controlled and change little in response to diet; hence, they are rarely used for nutritional status assessment. Calcium is primarily transported in the blood either freely or bound with albumin, and it is involved in muscle contraction and blood clotting (13). The regulation of calcium and phosphorus levels in the blood is influenced by vitamin D, calcitonin, and parathyroid hormone (15). Iron There are many types of nutrition-related alterations to red blood cell and hemoglobin synthesis, including iron-deficiency anemia, folate-related anemia, and vitamin B12- deficiency anemia. Other non-nutritional conditions may contribute to microcytic or macrocytic anemias and should be considered when evalu- ating the biomarkers. If anemia of chronic disease is present, increased ferritin levels are not representative of iron-deficient status. For example, individuals with arthritis who are truly iron-deficient may have elevated or normal serum ferritin levels. It is important to evaluate each biochemical test and disease state to determine if iron supplementation is warranted. Hyperglycemia Fasting blood glucose helps to identify abnormal glucose metabolism owing to diabetes or drugs. These tests are particularly important for those with obesity, a family history of heart disease, atherosclerosis, or diabetes. It is important to ensure that individuals fast for 12 hours before the blood draw. Markers of Inammation Many of the acute-phase proteins are used to assess the presence of inflammation. A common medication and nutri- tional interaction is between the anticoagulant, warfarin, and vitamin K, which compete with each other for the same binding site in the coagulation cascade (17). Clinical manifestations occur late and are nonspecific, and may also be related to other conditions or multiple nutrient deficiencies. These signs and symptoms may be caused by a disease, medication, or nutritional deficiency. Comorbidities The presence of other diseases often increases risk for malnutrition. Some diseases have symptoms that may appear similar to those resulting from nutritional deficiencies. Biotin and riboflavin deficiencies include scaly, red rashes on the face and around orifices, which should be not be confused with the facial rash often found on patients with systemic lupus erythematosus. But dietary assessment is difficult and must be done carefully to distinguish under- or malnutrition owing to diet alone (a primary deficiency) from that resulting from other causes (secondary deficiency) (20). Primary deficiency results from inadequate intake, which may be influenced by socioeconomic status and conditions such as alcohol abuse or eating disorders. Secondary nutrient deficiencies result from increased physiological needs, increased nutrient losses in feces and urine, and other causes. In planning interventions it may also be helpful to know about shopping and cooking habits and the frequency of meals consumed away from the home (5). Medications and dietary supplement intakes are important to consider when assessing dietary intake. Some medications provide nutrients, such as antacids containing relatively large amounts of calcium. There may be sources of amino acids, sugar, and vitamins and minerals in other medications as well. Dietary supplement intake of vitamins and minerals and other nutrients should also be included in assessing nutrient intakes. The use of other supplements, especially botanicals, may be helpful in assessing interactions with medications. The individual (or if a child is the patient, the parent or caretaker) is asked about intake over the last 24 hours. Probing is usually done to help the individual remember foods or beverages he or she may have forgotten. Memory aids and tools are used to promote an accurate estimation of portion sizes, including measuring cups and spoons, photographs of food in a known portion size, and food models. The individual should not be led to an assumed or socially acceptable answer; instead, open-ended questions should be asked. Computerized dietary assessment programs are now available for research purposes with a multiple-pass interview style that decreases underreporting (21). In the first pass, the individual recalls food and beverage intake for the designated time period. Finally, in the fourth and final pass, the interviewer questions the consumption of supplements and medications that contain nutrients. The disadvantages include the reliance on memory, thus making it inappropriate for individuals with a poor memory, and the fact that some foods may be forgotten or purposefully omitted (5,21). Because a computerized dietary assessment program is not used, it is also difficult to calculate nutrient intakes. Some simply present a list of common foods and ask the respondent to recall consumption of the food over the past year. This permits a rough estimate of nutrient intake, which may be useful in epidemiological studies in particular. Without adjustments for caloric intakes, intakes are usually grossly overestimated. There may also be biases with underreporting of socially unacceptable items or behaviors such as high-fat foods, alcohol, and so on. Food Records Food records are another method of collecting dietary intake for nutrient analysis. The individual records the brand names, cooking method, and ingredients of mixed dishes in household measurements (21). Forgetting to record intake and inaccurate estimation of volume and weights of foods and beverages are disadvantages to this method (5,21). Environmental assessment includes the identification of physical and social influences on intake. Influences in the Physical Environment on Intake Conditions within the household, access to food shopping and cooking facilities, and other factors may greatly influence intake. For those who have difficulties ambulating, the use of assistive devices should be queried because they can make the process of food preparation much easier. It may also be useful to identify the number of people in the home (5), the person responsible for purchasing and cooking food, and whether there are facilities to store and cook foods properly during periods of illness when the person may be shut in the house (5,22). Other factors to determine include whether a car is available and how far it is to the grocery or convenience store, avail- ability of foods at nearby stores, and the patient s ability to commute to and transport food from the store to the home (5). An environment that promotes physical activity also contributes to nutritional status. If necessary, efforts should be made to assist a patient with applications for food assistance programs (e. Family support and frequency of communication and activity with family and friends also need to be assessed because they too can influence dietary intake (18). In scleroderma, the mouth may become small, making it difficult for patients to feed themselves and consume adequate nutrients. Generic Quality-of-Life Indicators Evaluation of quality of life includes assessing physical ability and functional activity as well as the health-related emotional and social implications. Quality-of-life questionnaires are also available specifically for pediatric or adolescent patients. The most common measures include the Childhood Health Questionnaire, Pediatric Quality of Life Inventory Scales, and Quality of My Life Questionnaire (29). Arthritis-Specic Quality of Life Disease-specific quality-of-life questionnaires have been designed for many rheumatoid diseases. Table 1 lists the disease-specific quality-of-life measures for arthritis and related diseases. They are particularly useful because they provide specific information that is directly related to the disease. Indicators of malnutrition also include rheumatoid cachexia, which involves muscle wasting that is often replaced with fat (30). Even with good disease control and adequate caloric intake, skeletal muscle catabolism persists (31,32). Assessment of caloric and protein intake is important because inadequate intakes will further accelerate muscle loss. Muscle wasting also affects functional status and mobility, which may impair food shopping, meal preparation, and cleanup. As a result of the chronic inflammation, anemia of chronic disease is often present (10,11,34). Medication-related effects on biochemical indices of folic acid and iron status are also common. Some medications such as methotrexate also affect calcium and vitamin D status (17 19). Dietary and functional assessments should include attention to energy intake and problems related to obtaining, preparing, and eating food. Patients with social support may have a better quality of life, potentially moderating the impact of pain, depression, and physical disability (33). The disease is chronic and characterized by an age of onset before 16 years of joint swelling, heat, and pain and stiffness of unknown origin (10, 11) that occurs for 6 weeks or more (11). Disease characteristics often include inflammation, fever, damage/deformity of joints, and altered bone growth (10). In abnormal bone growth, one bone may be longer than another at times of accelerated growth and later become stunted. If the abnormal bone growth occurs in the leg, the child may compensate by bending the longer leg until the hips are level. Either arm-span or knee-height measurements are appropriate depending on the location of contractures and range in motion of joints.
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