bluuebunny/crossref_metadata_2025 huggingface dataset:
Melanocytogenesis and melanogenesis: genetic regulation and comparative clinical diseases
Authors: Alhaidari  , Olivry  , Ortonne
Published: March 2003

Murine models recently provided important information on the pathogenesis of pigmentation disorders. Multiple factors influence melanocyte function at various levels, such as melanoblast development and migration from the neural crest to peripheral sites, melanoblast differentiation into melanocytes, melanocyte survival and, finally, synthesis of melanosomes and melanins. Mutations affecting any of these steps result in hereditary hypomelanoses. In some of these diseases, melanocytes are absent, either because of a defect in migration of melanoblasts from the neural crest, their inability to survive and/or proliferate in colonized territories (piebaldism and Waardenburg syndromes), or because of programmed melanocyte destruction (e.g. vitiligo). In other entities, the melanocytes are present but functionally deficient (oculocutaneous albinisms and pigmentary dilutions). This comprehensive review will introduce the genetic regulation of melanocytogenesis and melanogenesis and the correlations between genetic abnormalities and hypopigmentation clinical disorders.
Morphologic and immunologic characterization of a canine isthmus mural folliculitis resembling pseudopelade of humans
Authors: Gross Thelma Lee , Olivry Thierry , Tobin Desmond
Published: March 2003

The clinical, histopathologic and immunopathologic features of a novel form of isthmus mural folliculitis in dogs, which resembles pseudopelade in humans, were characterized. Clinically, dogs exhibited variably distributed foci of alopecia that persisted without treatment or did not respond to immunosuppressive therapy. Histopathologically, mixed mononuclear cell infiltrates, largely lymphocytes, infiltrated the follicular isthmus. Occasionally, inflammation extended above and below the follicular isthmus but did not involve the hair bulb or the epidermis. Severe follicular atrophy and variable atrophy of sebaceous glands occurred in all dogs. Folliculotropic lymphocytes exhibited most commonly CD3 and CD8 (cytotoxic T cells). Autoantibodies specific for the lower hair follicle were detected in the serum of affected patients. Western immunoblotting demonstrated binding of these antibodies to multiple follicular keratinocyte proteins, including hair keratins and trichohyalin. Lack of hair regrowth (in contrast to canine alopecia areata), as well as location of inflammation and extreme atrophy of adnexal units are similar to findings seen in human pseudopelade.
Microbial flora and antimicrobial susceptibility patterns from dogs with otitis media
Authors: Colombini S. , Merchant S.R. , Hosgood G.
Published: March 2003

This study evaluated the middle ear microbial flora and antimicrobial susceptibility patterns from dogs with otitis media. Antimicrobial susceptibility patterns were obtained on 164 micro‐organisms from 107 ears of 82 dogs with otitis media that presented to Louisiana State University over a 12‐year period. The most common micro‐organisms isolated wereStaphylococcus intermedius(26.8%),Pseudomonas aeruginosa(23.2%), β‐haemolytic streptococcus (12.8%),Proteusspp. (11.0%) andStaphylococcus epidermidis(8.5%). Antimicrobial susceptibility testing was performed on all isolates employing the disk diffusion method (Kirby‐Bauer). Minimum inhibitory concentration (MIC) testing for enrofloxacin and ciprofloxacin was performed on 10 of the 18P. aeruginosaisolates found to be resistant to enrofloxacin on Kirby‐Bauer. Of these isolates, 6 (60%) were susceptible, 1 (10%) was intermediate and 3 (30%) were resistant to enrofloxacin. Eight of these isolates (80%) were susceptible to ciprofloxacin, 1 (10%) showed intermediate susceptibility and 1 (10%) was resistant.
Cyclosporine decreases skin lesions and pruritus in dogs with atopic dermatitis: a blinded randomized prednisolone‐controlled trial*
Authors: Olivry Thierry , Rivierre Christine , Jackson Hilary A. , Murphy K. Marcy , Davidson Gigi , Sousa Candace A.
Published: March 2003

Abstract During the last decade, oral cyclosporin (CsA) has proven to be effective, in randomized controlled trials, for the treatment of atopic dermatitis (AD) in human patients. The purpose of this blinded randomized controlled trial was to test the hypothesis that CsA was successful in reducing the gravity of clinical signs of AD in dogs. Thirty dogs with nonseasonal AD were randomly allocated to receive an oral solution of either NEORAL CsA (5 mg kg−1) or prednisolone (0.5 mg kg−1) once daily for 6 weeks. Before, and 3 and 6 weeks after therapy, skin lesions were graded by clinicians using the Canine AD Extent and Severity Index (CADESI). Pruritus was assessed by the owners using a visual analog scale (PVAS). In both groups, CADESI and PVAS values were significantly lower at 6 weeks post treatment than before the initiation of therapy (Friedman test, P < 0.0004). The percentage reductions in CADESI and PVAS values from baseline were not statistically different between groups (Mann–Whitney test, P > 0.3). In this experiment, the tolerability and safety of oral CsA and prednisolone appeared similar. One‐fifth of dogs given oral CsA occasionally developed diarrhoea or soft stools. One dog that was given CsA developed a generalized papillomatous skin eruption during the second half of the trial. Our study provides randomized controlled trial evidence that CsA reduces the severity of clinical signs in dogs with nonseasonal AD. Moreover, the anti‐allergic efficacy of CsA appears comparable with that of prednisolone. We propose that oral CsA should be considered as a valuable alternative to glucocorticoid therapy in dogs with AD.
Transfer of passive cutaneous anaphylaxis to Malassezia pachydermatis by the serum of atopic dogs with Malassezia dermatitis
Authors: Morris D. O. , Deboer D. J.
Published: March 2003

In atopic dogs with Malassezia dermatitis (MD), type 1 hypersensitivity reactions and circulating serum IgE reactive to M. pachydermatis extracts have been reported. The purpose of this study was to evaluate the functionality of anti‐Malassezia IgE by the transfer of passive cutaneous anaphylaxis (PCA testing). Three nonatopic dogs were used as recipients. Two test sera were utilized: pooled sera from 10 atopic dogs with MD that were skin test positive to M. pachydermatis extract; and serum from an atopic dog with MD that exhibited high levels of anti‐Malassezia IgE on an ELISA assay. One aliquot of each untreated serum, one aliquot of each serum heated at 56 oC for 4 h and two aliquots of the ELISA‐positive serum adsorbed with either mouse anticanine IgE or bovine serum albumin (as a control) were utilized. Six serial dilutions of all six aliquots were injected intradermally in triplicate, along with a 20 µg mL−1 extract of M. pachydermatis to rule out prior sensitization to the yeast. At 24‐, 48‐ and 72‐h intervals, the yeast extract was injected intradermally at the sites of prior serum injections and wheal/flare responses were graded 0–4+ compared with saline and histamine controls. Through 72 h, all dogs showed > 2+ reactions at the injection sites of both the untreated sera and the BSA‐treated sera (titers = 1:64), but no reactions at the sites of heat‐inactivated and IgE‐adsorbed sera. These results support the transfer of PCA by anti‐Malassezia IgE and implicate it to be functional in type 1 hypersensitivity.

 Funded by the Canine Health Foundation of the American Kennel Club.
Isolation and characterization of Pseudomonas aeruginosa from sheep with fleece rot in northern and middle Jordan
Authors: El‐Sukhon Saeb N.
Published: March 2003

Abstract A total of 162 sheep fleece samples were collected from 2315 sheep clinically examined for evidence of dermatitis. The sheep belonged to 32 flocks raised in northern and middle Jordan. Eighty‐three samples showed no obvious abnormalities, whereas the remainder showed exudation (79 samples), fleece discoloration (18) and fleece roughness (40) and abscesses (7). Seventeen Pseudomonas aeruginosa isolates were obtained from these samples. Antibacterial resistance in vitro was common; resistance to tetracycline, amoxycillin, erythromycin and cotrimoxazole was shown by > 90% of the isolates. Resistance to norfloxacin (29.4% of isolates), ciprofloxacin (17.6%) and amikacin (17.6%) was also demonstrated. Fourteen isolates were serum resistant when assessed after 1–3 h incubation in sheep and calf sera, and their count increased by 2–2.9 and 2.5–3.5 respectively.
Gap colonization by weeds in a wheat crop grown under different cultivation regimes
Authors: FELDMAN  , ALZUGARAY  , TORRES  , LEWIS
Published: March 2003

The effects of tillage systems (mouldboard plough, chisel, disk and non‐tillage, over 3 years) and gap openings during August and October of 0, 0.30 m × 0.30 m and 0.45 m × 0.45 m on the weed community were investigated in a wheat (Triticumaestivum L.) crop. Weed flora composition and species abundance were recorded in August, September and November and the data analysed with
MULVA programs and non‐parametric tests. The tillage system was more important than the timing or gap size on the weed floristic composition, and the changes in weed communities were evident within a 3‐year period in spite of herbicide use. Less disturbing tillage systems (non‐tillage and chisel plough) allowed the build‐up of a more diverse community, whereas the most disturbing one (mouldboard plough) prevented high diversity in the weed community.
A possible involvement of gibberellin in the mechanism of Avenafatua resistance to triallate and cross‐resistance to difenzoquat
Authors: RASHID  , O'DONOVAN  , KHAN  , BLACKSHAW  , HARKER  , PHARIS
Published: March 2003

Avena fatua L. populations from numerous fields in Alberta have simultaneously developed resistance to recommended rates of two dissimilar herbicides, triallate and difenzoquat. We used exogenous applications of gibberellic acid (GA3) to investigate the possibility that endogenous gibberellins were involved in the A. fatua's resistance mechanism. For control plants, without applied GA3, shoots of the most resistant (R) populations emerged more rapidly and elongated faster than shoots of the susceptible (S) populations. Increases in shoot elongation in response to exogenous GA3 were significantly lower in R populations compared with S populations. This suggests that R populations may have elevated endogenous gibberellin levels, relative to S populations. Additionally, inhibition of S population shoot elongation and shoot anatomical abnormalities caused by relatively low concentrations of triallate and difenzoquat could be prevented by exogenous application of GA3. These results suggest that there may be a phytohormonal involvement in the mechanism of triallate/difenzoquat resistance in A. fatua. That is, higher endogenous gibberellin levels in R populations may result in meristematic growth that is rapid enough to preclude phytotoxic levels of these herbicides from reaching the shoot meristem, which is the likely site of action.
A rapid reliable test for screening aryloxyphenoxy‐ propionic acid resistance within Alopecurus myosuroides and Lolium spp. populations
Authors: LETOUZÉ  , GASQUEZ
Published: March 2003

A reliable seedling bioassay was developed and tested for the rapid screening for resistance to aryloxyphenoxypropionic (APP) herbicides in Alopecurus myosuroides and Lolium spp. populations. It is based upon the difference in coleoptile length of resistant and susceptible A. myosuroides and Lolium seedlings, respectively, exposed to fenoxaprop‐P acid and diclofop acid solution for 6 days in a plastic box. A 6 mg L−1 fenoxaprop‐P acid solution was selected as the best concentration for a reliable screening of resistant biotypes within A. myosuroides populations. At this concentration, coleoptile lengths of susceptible and resistant seedlings were shorter and longer than 10 mm respectively. Similarly, resistant seedlings within Lolium populations were easily detected at 10 mg L−1 diclofop acid. At this concentration, coleoptile lengths of susceptible and resistant seedlings were shorter and longer than 20 mm respectively. For both populations, the coleoptile length distributions appear to discriminate between two kinds of APP‐resistant biotypes (highly and slightly resistant).
Effect of temperature and humidity on the longevity of Orobanche seeds
Authors: Kebreab  , Murdoch
Published: March 2003

The effects of moisture and temperature on seed longevity were studied over periods of up to 426 days in three species of Orobanche. Saturated salt solutions were used to achieve equilibrium relative humidities (e.r.h.) between 11% and 85% at temperatures of 20–60 °C. The viability equation describing loss of viability in these conditions applied to the three species such that the lower the temperature and lower the equilibrium relative humidity the greater the longevity. The initial viability differed between species with the seed lot of Orobanche crenata having the lowest viability. However, the relative effect of temperature on longevity and the relative sensitivity of seed longevity to changes in equilibrium relative humidity were the same in all species. Longevity, estimated by the standard deviation of the seed survival curves was greater in Orobanche aegyptiaca and O. crenata than in Orobanche minor, being for example about 100, 103 and 49 days, respectively, at 40 °C, 50% e.r.h. Accurate prediction of longevity is necessary to understand and quantify the population dynamics of weeds and will help the farmer to optimize control measures such as solarization. Taken in conjunction with published data on loss of viability of imbibed seeds, the annual loss of viability on a typical Eritrean farm is predicted to be about 38%.
Competition between sugarbeet and Sinapis arvensis and Chenopodium album, as affected by timing of nitrogen fertilization
Authors: Paolini  , Principi  , Froud‐Williams  , Del Puglia  , Biancardi
Published: March 2003

The effects of timing of N fertilization (early, standard or late) on competition between two sugarbeet cultivars (Ritmo, semi‐prostrate; and Rizor, erect) and two weeds (Sinapis arvensis and Chenopodium album) were studied over 2 years at Viterbo. In both years, time of N fertilization did not influence biomass, yield and yield quality of the weed‐free crop, but early N fertilization gave higher crop biomass reduction in the presence of S. arvensis and lower crop biomass reduction in the presence of C. album. Root and sucrose yield responded to competition in the same way as biomass. However, percentage reductions were higher, as both weeds affected harvest index. The two cultivars showed the same response to competition. At the weed densities studied, crop competitive ability was favoured by late N fertilization in the presence of S. arvensis and by early N fertilization in the presence of C. album. Crop competition only reduced seed production by C. album but lowered seed germination of both weeds.
Spatial distribution of weeds in arable crops: are current sampling and analytical methods appropriate?
Authors: Rew L J , Cousens R D
Published: March 2003

This paper reviews the literature concerning the spatial distribution of weeds; highlighting the limitations of our current sampling and analytical methodologies, and suggesting how these inadequacies can be addressed. Most research studies have used discrete sampling, i.e. weeds are counted within a quadrat, on a grid basis. Few have mapped weeds at a whole‐field scale, either with a resolution appropriate to spraying operations or key ecological processes. Statistical analyses used to describe the data can be divided into two main types, spatially implicit (also at the scale of the sampling unit) or spatially explicit, in which the location of individuals is included in the analyses. Spatially implicit methods can be strongly affected by quadrat size and mean density and are of doubtful benefit. More attention is required to address sampling resolution issues for spatially explicit methods. Our understanding of the formation and dynamics of spatial pattern, as well as predicting the consequences of site‐specific management, can be improved with models. Unfortunately, most models consider only newly expanding patches and appear incapable of predicting spatial distributions when an area has been fully invaded. More detailed biological information is required if models are to become more realistic and informative. We also need to ensure that we understand the spatial processes in the context of the whole field environment, to optimize the success of site‐specific weed management in the longer term.
Resistance of Raphanus raphanistrum to chlorsulfuron in the Republic of South Africa
Authors: Smit J J , Cairns A L P
Published: March 2003

Herbicide resistance poses a substantial threat to the agricultural industry throughout the world and during the past decade several reports regarding herbicide resistance have been published. Raphanus raphanistrum L., from two wheat farms located in the winter rainfall region of South Africa, showed indications of resistance to chlorsulfuron. Seeds from these suspected resistant biotypes as well as seeds from a susceptible biotype were collected and transported to the ARC‐Small Grain Institute for herbicide resistance studies. Herbicides registered for R. raphanistrum control, i.e. chlorsulfuron, MCPA and bromoxynil, were used in this study. Significant differences in the degree of control were found between the susceptible and two resistant biotypes, when treated with chlorsulfuron. The LD50 values for the resistant biotypes (WR 1 & WR 2) were 45 and 11.3 g a.i. ha–1, respectively, whereas the LD50 value for the susceptible biotype was 5.6 g a.i. ha–1. The almost eightfold difference between the susceptible and resistant biotype (WR 1), indicated that resistance has developed to chlorsulfuron. Only twofold resistance was established between the other resistant biotype (WR 2) and the susceptible biotype. Significant differences between herbicide rates were also established with the MCPA and bromoxynil experiments. No significant difference could, however, be found between the susceptible and resistant biotypes when treated with MCPA and bromoxynil, indicating the importance of different modes of action of herbicide as a strategy to prevent herbicide resistance.
Light, temperature and burial depth effects on Rumex obtusifolius seed germination and emergence
Authors: Benvenuti S , Macchia M , Miele S
Published: March 2003

Trials were carried out to investigate the effects of light and temperature on germination of Rumex obtusifolius L. After several months of storage, seeds gradually lost dormancy and became photosensitive. Thermal optima for germination were between 20 °C and 25 °C in light or in darkness. At lower temperatures there was a greater demand for light, so that the greatest differences in germination percentage (between low and high temperatures) were found within the 10–15 °C temperature range. The calculated thermal minima (x‐intercept method) in light and darkness were 8.3 °C and 6.1 °C respectively. Daily temperature fluctuation increased germination even after seed irradiation with far‐red light, suggesting a lower demand for the far‐red‐absorbing form of phytochrome. Seed burial inhibited germination in proportion to depth; however, germination inhibition was independent of seed phytochrome photo‐equilibrium, which had been diversified by seed pretreatment with light. Seedlings did not emerge when seeds were buried >8 cm deep. Recovery of ungerminated seeds showed that excessive burial did not impede seedling emergence but rather prevented seed germination. However, this induction of dormancy was lost once germination processes were activated (24–48 h at 20 °C) that made germination irreversible. Temperature was also involved in inhibition, and low temperature (<15 °C) induced the least inhibition. This is discussed in terms of processes of respiration and fermentation in buried seeds.
Propanil activity, uptake and metabolism in resistant Echinochloa spp. biotypes
Authors: Lopez‐Martinez N , Gonzalez‐Gutierrez J , De Prado R
Published: March 2003

Field resistance of Echinochloa spp. to propanil has been previously reported in Costa Rica, Colombia and Arkansas (USA). In this study, the mechanism of resistance was investigated in three resistant (R) and three susceptible (S) biotypes. The shoot fresh weight reduction in pot‐grown plants from a post‐emergence spray of propanil at 2.44 kg a.i. ha−1 on biotypes R/S from Costa Rica, Colombia and Arkansas was 35/98%, 25/79% and 20/82% respectively. In vitro chlorophyll fluorescence data from leaf tissue incubated in propanil showed that photosynthesis was inhibited in all biotypes, indicating that the propanil‐binding site and enzyme were not altered. After transfer to herbicide‐free solution, photosynthesis recovered only in resistant biotypes, indicating that the mechanism of resistance was caused by enhanced metabolism of the herbicide. Simultaneous treatment with fenitrothion, an aryl acylamidase inhibitor, prevented the recovery of photosynthesis in leaf tissue in two resistant biotypes. In contrast, the cytochrome P450 mono‐oxygenase inhibitor, 1‐aminobenzotriazole, did not prevent recovery from propanil in leaf tissue. Application of 14C‐propanil to the second leaf of intact Echinochloa plants showed that c. 90% of the radioactivity remained in the treated leaf for up to 72 h after application. No major differences in translocation between R and S biotype plants were found. TLC analysis of tissue extracts from the treated leaves showed substantially less radioactivity associated with propanil, present after 72 h in rice or in the three R biotypes, compared with S biotypes.
Do maize cultivars demonstrate tolerance to the parasitic weed Striga asiatica?
Authors: Gurney A L , Taylor A , Mbwaga A , Scholes J D , Press M C
Published: March 2003

Summary Three cultivars of maize (TMV‐1, Katumani and Staha) were grown in the absence and presence of the root hemiparasite Striga asiatica in the field in eastern Tanzania. Infested Katumani and TMV‐1 plants yielded 22% and 25% less grain than uninfested plants; however, the grain yield of Staha was similar in both infested and uninfested plants. Measurements of gas exchange and the quantum yield of photosystem II (ΦPSII) revealed that photosynthesis and stomatal conductance were lower in infested plants of TMV‐1 and Katumani than in control plants, but were not as severely affected in S. asiatica‐infested plants of the cultivar Staha. Chlorophyll fluorescence measurements, particularly the Fv/Fm ratio, showed that S. asiatica predisposed TMV‐1 to greater photoinhibition than control plants after exposure to irradiances of 2000 µmol quanta m−2 s−1 in the field during the day. The lowering of the Fv/Fm ratio resulted from a decrease in Fm rather than in Fo. In contrast to TMV‐1, infested Staha plants were not more photoinhibited than control plants by mid‐afternoon. We suggest that the ability of Staha to yield well in the presence of S. asiatica may result, in part, from the ability of this cultivar to maintain high rates of photosynthesis in the field, thus limiting the extent of photoinhibition.
Influence of developmental stage and time of assessment on hot water weed control
Authors: Hansson D , Ascard J
Published: March 2003

SummaryThe influence of plant developmental stage in hot water weed control was studied on the test weedSinapis albain field experiments. The dose was measured as thermal energy in the hot water (kJ m−2) and the response as reduction in plant weight. The energy dose for a 90% reduction in plant weight was 340 kJ m−2at the two‐leaf stage, which is one‐third of the energy required for the same reduction at the six‐leaf stage. Treatment at an early stage saves energy, increases the driving speed and lowers the costs. Hard surface areas with naturally developed weeds were used to study the required treatment interval and the influence of time of assessment on the reduction in weed cover. The required treatment interval was 25 d on average, which is similar to that of flame weeding. A longer lasting effect requires a higher energy dose. A 50% higher energy dose was needed to obtain a 90% reduction in weed cover that lasted for 15 d instead of 7 d. After 3–4 weeks, hardly any reduction could be recorded because of regrowth of perennial weeds. However, hot water weed control has a potential on urban hard surfaces and railroad embankments, especially where the use of herbicides is restricted.
Altered acetyl‐coenzyme A carboxylase confers resistance to clethodim, fluazifop and sethoxydim in Setaria faberi and Digitaria sanguinalis
Authors: Volenberg D , Stoltenberg D
Published: March 2003

Summary Populations of Setaria faberi and Digitaria sanguinalis cross‐resistant to sethoxydim and fluazifop‐P‐butyl were identified in a vegetable cropping system in Wisconsin, USA, in 1991 and 1992 respectively. Experiments were conducted with partially purified acetyl‐CoA carboxylase (ACCase) to determine whether resistance to sethoxydim and other ACCase inhibitors in S. faberi and D. sanguinalis resulted from altered enzyme activity. Based on I50 values (the herbicide dose that inhibited ACCase activity by 50% compared with untreated ACCase), ACCase of the resistant accession of S. faberi was 4.8‐, 10.6‐ and 319‐fold resistant to clethodim, fluazifop‐P acid and sethoxydim, respectively, compared with that of the susceptible accession. Similarly, ACCase of the resistant accession of D. sanguinalis was 5.8‐, 10.3‐ and 66‐fold resistant to clethodim, fluazifop‐P acid and sethoxydim respectively. These results indicated that resistance to ACCase inhibitors in these accessions of S. faberi and D. sanguinalis resulted from an altered ACCase enzyme that confers a very high level of resistance to sethoxydim.
Occupational protein contact dermatitis caused by meat and fish
Authors: Boehncke MD Wolf‐Henning , Pillekamp MD Hans , Gass MD Steffen , Gall MD Helmut
Published: March 2003

Background Protein contact dermatitis is a form of contact dermatitis possibly triggered by proteinaceous allergens.

Materials and methods We report two patients with a history of erythematous and urticarial skin reactions followed by transformation into prolonged papular symptoms upon contact with proteinaceous material.

Results The symptoms reported by the patients were reproducible by skin testing with meat (cow) and fish (salmon). Both patients experienced extracutaneous manifestations after ingestion of meat and fish, as proven by oral challenge. Specific immunoglobulin E (IgE) antibodies were detected in the patients’ blood.

Conclusions Both cases meet all major criteria of protein contact dermatitis, suggesting IgE‐mediated immediate‐type hypersensitivity with late‐phase cutaneous reactions.
Cytokines in leprosy, II. Effect of treatment on serum cytokines in leprosy
Authors: Moubasher Alaa El‐Din A. , Kamel ; Neveen A. , Zedan Hatem , Raheem Diaa El‐Din Abdel
Published: March 2003

Background Multidrug therapy (MDT) causes a decrease in the bacterial burden in leprosy patients. Does the decrease in the antigenic stimulation of the immune system have an effect on cytokine production?

Methods The effect of treatment on serum cytokines was evaluated in 36 leprosy patients and 35 reactional leprosy patients and compared with that in 20 age‐ and sex‐matched healthy individuals. The enzyme‐linked immunosorbent assay (ELISA) technique was used to measure serum levels of interleukin‐2 receptor (IL‐2R), interleukin‐10 (IL‐10), and interleukin‐1beta (IL‐1β) before and after treatment. These cytokines represent T‐helper 1 (TH1), T‐helper 2 (TH2), and macrophage cytokines, respectively.

Results The studied serum cytokines were significantly reduced after 1 year of treatment in leprosy patients. The degrees of reduction were significantly positively correlated with a reduction in the bacterial index (BI) and morphologic index (MI). After 1 year of MDT (but not 6 months), paucibacillary (PB) patients showed a significant reduction in all the studied serum cytokines to levels comparable with those of healthy controls. Multibacillary (MB) patients also showed a significant reduction in all the studied serum cytokines, but the levels were still significantly higher than those of healthy controls. Leprosy patients with high levels of serum IL‐1β were more susceptible to the development of reactions after the initiation of treatment. Corticosteroid therapy of reactional patients resulted in a significant reduction in the studied serum cytokines to levels similar or lower than those of nonreactional leprosy patients. The dose of steroids showed a significant positive correlation with the amount of decrease in IL‐1β.

Conclusions MDT caused a reduction in serum cytokines correlated with a reduction in the bacterial burden. It is advisable to continue MDT for PB patients for 1 year. Serum IL‐1β levels may have a prognostic value for the susceptibility of leprosy patients to the development of reactions.
Eruption of human immunodeficiency virus seroconversion
Authors: Sapadin Allen N. , Gelfand Joel M. , Gumprecht Jeffrey , Gordon Marsha , Rudikoff Donald
Published: March 2003

A 34‐year‐old Caucasian man, previously in excellent health, was admitted to Mount Sinai Hospital in September 1996 with an acute illness, including high fevers, malaise, sore throat, and a mucocutaneous eruption. On examination, he had a temperature of 38.5 °C. Cutaneous findings included a severe seborrheic dermatitis and an exanthem characterized by multiple erythematous macules and papules, some with a hemorrhagic center, distributed on the trunk and proximal extremities ( Fig. 1). Subtle palmar petechiae were noted. The mouth contained an enanthem with palatal petechiae and a well‐circumscribed erosion (
Fig. 2). Koplik’s spots were not present. Hepatosplenomegaly and lymphadenopathy were absent. Complete blood count revealed a white blood count of 2600 with a differential of 46% polymorphonuclear cells, 25% bands, 25% lymphocytes, and 4% monocytes. His hemoglobin was 11 g/dL and his platelet count was 90,000. A lymphopenia (0.7 (normal range 1.0–4.5 × 1000)) and an elevated PTT were also present. The routine biochemistry profile was within normal limits. Monospot was negative. There were no antibodies to hepatitis B or C, Coxsackie virus, Epstein–Barr virus, measles, herpes, toxoplasmosis, or cytomegalovirus antigen. The patient was immune to measles. Rapid plasma reagin (RPR) was nonreactive. Two months prior to presentation, human immunodeficiency virus (HIV) antibody testing was negative.

Exanthem characterized by multiple scattered erythematous macules and papules on the trunk

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Enanthem characterized by palatal petechiae and well‐circumscribed erosion

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A biopsy specimen from a lesion on the upper part of the chest demonstrated a mild interface dermatitis ( Fig. 3), consistent with a drug reaction or viral exanthem. Acid fast, Dieterle, and Gram stains of the biopsy specimen failed to reveal microorganisms. Serological testing for HIV DNA by polymerase chain reaction (PCR) was positive. PCR testing for HIV RNA recorded in excess of 7 million copies/mm3. Triple antiretroviral therapy with Saquinavir, AZT, and 3TC was initiated. The eruption cleared completely within one week of its onset. Six weeks later, seroconversion to HIV antibody positivity occurred. Eight weeks after starting therapy, the patient experienced severe nausea and vomiting and became icteric, and all medications were withdrawn. The patient recovered and has not experienced any further illness in 1 year of follow‐up.

Photomicrograph of biopsy specimen demonstrating mild interface dermatitis (hematoxylin and eosin; magnification, 200×)

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Tinea pedis et unguium in the Muslim community of Durban, South Africa
Authors: Raboobee Noufal , Aboobaker Jamila , Peer Abdool Kader , Micro Mmed
Published: March 2003

Background In a pilot study performed in eight mosques in the Durban area, it was found that the prevalence of tinea pedis et unguium in the adult Muslim male population regularly attending mosques was higher than in the nonMuslim male population. The aims of the present study were: (i) to determine the prevalence of tinea pedis et unguium in the adult Muslim male population regularly attending mosques; (ii) to investigate the role of mosque carpets and ablution areas in the spread of infection; and (iii) to develop strategies to combat the infection.

Method Seventy‐eight regular worshippers comprising adult Muslim males, chosen at random from five mosques in the Durban area, were examined for clinical evidence of tinea pedis et unguium. Skin scrapings and nail clippings were taken from clinically infected individuals and submitted for microscopy and culture for fungal organisms. A control group, comprising 72 nonMuslim adult male office workers from the administration departments of King Edward VIII Hospital, was similarly examined. In addition, scrapings from high traffic areas of the mosque carpets and swabs from the ablution areas were cultured for fungi.

Results In the mosque group, it was found that the prevalence of tinea pedis et unguium was 85%, taking either microscopy or culture positivity as indicative of infection. In the control group, the prevalence was 41%. Thus a statistical difference of 44% (P < 0.0001) between the two groups was demonstrated. Dermatophytes and yeasts were isolated from the carpets and/or floors of the ablution areas in all the mosques under investigation.

Conclusions The high prevalence of tinea pedis et unguium among regular male worshippers in the Muslim community can be attributed to the spread of fungal organisms in the communal ablution areas and prayer carpets of the mosques. Strategies to combat this spread of infection are being developed. These strategies are expected to find important practical applications in other communal environments, such as gymnasia, health spas, swimming pools, changing rooms of sports clubs, public showers, and even hotels.
The diagnostic role of the in vitro drug‐induced interferon‐γ release test in Stevens–Johnson syndrome
Authors: Halevy Sima , Cohen Arnon D. , Livni Ella
Published: March 2003

Background Drug‐related T‐cell activity in cutaneous drug reactions may be assessed by in vitro cytokine release tests. The diagnostic role of in vitro drug‐induced interferon‐γ (IFN‐γ) release was evaluated in a patient with Stevens–Johnson syndrome.

Case report Stevens–Johnson syndrome was diagnosed in a 58‐year‐old man, treated with colchicine (1 mg daily for 39 days) and allopurinol (300 mg daily for 13 days). Based on a clinical–epidemiologic score, allopurinol was more likely to be the causative agent. In vitro drug‐induced IFN‐γ release test was conducted on this patient and on two controls, using an enzyme‐linked immunoabsorbent assay (ELISA) technique. Increased IFN‐γ release was observed following an in vitro challenge of the patient’s lymphocytes with allopurinol, but not following in vitro challenge with colchicine. An in vitro challenge with allopurinol in two control patients, treated with allopurinol without adverse drug reactions, did not induce a significant increase in IFN‐γ release.

Conclusions The role of allopurinol as the drug responsible for the induction of Stevens–Johnson syndrome in our patient was confirmed by in vitro allopurinol‐induced IFN‐γ release, which may indicate a drug‐specific immune response.
Perianal Crohn's disease
Authors: Morales María Susana , Marini Mario , Caminero Mirta , Caglio Patricia
Published: March 2003

A 13‐year‐old girl with a history of 4 months of perianal skin lesions is described. Physical examination revealed three 0.5 Ï 1‐cm red, swollen, fleshy, skin tags extending from the perianal area to the perineum ( Fig. 1). The patient reported intermittent fever, diarrhea, and abdominal pain, and her body weight was below the third percentile for her age.

Red swollen, fleshy, skin tags extending from the perianal area to the perineum

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Laboratory studies showed an erythrocyte sedimentation rate of 101 mm/h; hematocrit of 26%; white blood cell count of 9800/mm3 ; serum iron of 15 mg/L (normal value (NV), 60–160 mg/L); ferritin of 43.4 μg/L (NV, 12–150 μg/L); transferrin of 203 mg/100 mL (NV, 200–400 mg/100 mL); transferrin saturation of 6% (NV, 20–50%); hypoalbuminemia; negative purified protein derivative (PPD), cytomegalovirus (CMV), human immunodeficiency virus (HIV), venereal disease research laboratory (VDRL), and antinuclear antibody tests; and Toxoplasma titers of 1/16, Van de Kamer 1.67 g/day. A barium examination revealed marked irregularity of the descending colon, and a colonoscopy showed uneven areas of mucosal edema and pseudopolyps in the transverse and descending colon, associated with irregular thickening and stenosis.

Histopathologically, large intestine and skin lesions consisted of noncaseating epithelioid and giant cell granulomas ( Fig. 2). Cultures for acid‐fast bacilli and fungi were negative, and under polarized light no foreign bodies were seen.

Noncaseating epithelioid and giant cell granulomas (hematoxylin and eosin, original magnification ×100)

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Treatment with metronidazole (250 mg three times a day), prednisone (0.5 mg/kg/day), and acetylsalicylic acid (75 mg/kg/day) was moderately effective. Vitamin, folic acid, and iron supplements were also added.
The significance of stress hormones (glucocorticoids, catecholamines) for eruptions and spontaneous remission phases in psoriasis
Authors: Weigl Bea A.
Published: March 2003

Austria

Background  In an earlier paper, it was described how acute eruptions of psoriasis may be produced in phases of immune deficiency and in the presence of bacterial antigen‐releasing inflammatory foci, whereas clinical spontaneous remissions are produced in phases of immunologic activity. Therefore, it was of interest to investigate whether the stress hormones cortisol/epinephrine are involved in triggering such deficiency and activity phases.

Methods  During a series of investigations lasting up to 3 years in 95 patients, the following were determined: cortisol/epinephrine levels, polyclonal serum immunoglobulins IgM, IgG, and IgA, total serum IgE, complement C3 and C4 proteins, T cells and subpopulations, as well as streptococcal titers ASO/ADNase B, severity index (PASI)

Results  Phases of clinical inactivity are associated with the mechanism, ‘‘immunologic regulation,’' where antibacterial titers are elevated, but all other parameters are unremarkable. Eruption phases (in 32 of 95 patients) showed absolute increases in serum cortisol levels and antibacterial titers, and decreases in serum epinephrine (adrenaline) levels. Phases of spontaneous remission (in 25 of 32 patients) showed, in contrast to the eruption phases, absolute increases in serum epinephrine levels, and significant falls in serum cortisol levels and bacterial titers.

Conclusions  On the basis of these results, the participation of the immune system is confirmed in the pathogenesis of psoriasis, which is subject to control by higher neurohormonal systems. Cortisol may be involved in the clinical eruption phase, and epinephrine in the remission phase. Both hormones are true antagonists and have important effects on the human immune system if produced in excess via the pituitary–adrenal axis. Infection with Streptococcus pyogenes is an additional trigger for the dermatosis.
Recessive dystrophic epidermolysis bullosa complicated with nephrotic syndrome due to secondary amyloidosis
Authors: Gündüz Kamer , Vatansever Seda , Türel Aylin , SÛen Sait
Published: March 2003

A 15‐year‐old young woman had a history of recurrent blisters and erosions on her whole body and oral mucosa since birth. There were patchy areas of cicatricial alopecia on the scalp and flaccid blisters and erosions on the back, buttocks, and distal portions of the extremities ( Fig. 1). Mitten‐hand deformity was observed on the hands and feet (
Fig. 2). The mobility of the tongue was limited due to fibrosis of the frenulum. Dental and ocular examinations were normal. Her mother and father were first‐degree relatives and no other relatives were known to have blistering disorders.

Blisters and erosions on the back, buttocks, and upper extremities

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Mitten‐hand deformity on the hands and feet as well as erosions on the lower extremities

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Skin biopsy specimens were stained with periodic acid–Schiff (PAS) and antilaminin, anticollagen IV antibodies by indirect immunohistochemistry. There was a separation between the epidermis and dermis. Regular linear homogeneous staining of the basement membrane with PAS was observed between the epidermis and the roof of the bullae ( Fig. 3). While laminin immunoreactivity was positive irregularly in the lamina lucida, deposition of collagen IV was observed as a homogeneous sheet in the lamina densa. Both the positive immunoreactivities for laminin and collagen IV were at the roof of the bullae. There was an inflammatory reaction in the dermis and within the bullae.

Bullae (asterisks) between the epidermis and dermis; basement membrane (arrow) staining homogeneously at the roof of the bullae. The inflammatory reaction is also indicated (star) (PAS, ×100)

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Hematologic and biochemical tests revealed anemia (hemoglobin 8.3 g/dL, hematocrit 28.5%, ferritin 12.7 ng/mL), hypoalbuminemia (2.12 g/dL), and proteinuria (2016 mg/24 h).Creatinine clearance was 9 mL/min. Rectal biopsy was negative for amyloidosis; the diagnosis of amyloidosis was established by means of renal biopsy ( Fig. 4). Immunohistochemical staining showed amyloid A type amyloid deposits in the renal glomerulus. Staphylococcus aureus grew frequently in skin cultures.

Segmental amyloid deposition at the vascular pole of the glomerulus (hematoxylin and eosin, ×400)

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Topical antiseptic dressings were applied and systemic antibiotics were used for secondary bacterial infection. Vitamin E (200 IU/day) and phenytoin (5 mg/kg/day) were administered with little success. Only protein replacement therapy could be administered for secondary amyloidosis and nephrotic syndrome because of renal impairment. The patient is still under the control of the Departments of Dermatology and Nephrology.
Effect of palmitic acid on neutrophil functions in vitro
Authors: Akamatsu Hirohiko , Niwa Yukie , Matsunaga Kayoko
Published: March 2003

Background  It has been shown that in acne comedones the proportion of linoleic acid is markedly decreased, while palmitic acid is significantly increased. We previously reported that the decreased proprtion of linoleic acid, which markedly suppresses neutrophil reactive oxygen species (ROS) generation and phagocytosis, contribute to the worsening of acne inflammation. The aim of this study was to examine the effect of palmitic acid on neutrophil functions in vitro.

Methods  We investigated the effect of palmitic acid on inflammatory parameters such as neutrophil chemotaxis, phagocytosis, and ROS generation. Reactive oxygen species generation in a cell‐free, xanthine‐xanthine oxidase system was also assessed. The species examined were superoxide radical anion (O2–), hydrogen peroxide (H2O2), and hydroxyl radical (OH·).

Results  Palmitic acid significantly decreased H2O2 generation both by neutrophils and in the xanthine‐xanthine oxidase system, while neutrophil chemotaxis and phagocytosis as well as O2– and OH· generation by both systems were not markedly affected in the presence of palmitic acid.

Conclusions  The present study suggests that palmitic acid may be involved in the pathogenesis of acne inflammation from a standpoint of oxidative tissue injury.
Treatment of cutaneous leishmaniasis with a combination of allopurinol and low‐dose meglumine antimoniate
Authors: Momeni Ali Z. , Reiszadae Mohamad Reza , Aminjavaheri Malihalsadat
Published: March 2003

The objective of this study was to compare the efficacy of a combination of allopurinol (AL) and low‐dose meglumine antimoniate (MA) with standard‐dose MA in cutaneous leishmaniasis caused by Leishmania major.

An open, controlled study was performed. Seventy‐two patients were randomly selected from volunteers with cutaneous leishmaniasis living in a hyperendemic area. Exclusion criteria included pregnancy, nursing vs. gestation, age less than 5 years, and duration of disease of more than 4 months. Each patient received MA (60 mg/kg/day) or AL (20 mg/kg/day) plus low‐dose MA (30 mg/kg/day) for 20 days, and was followed up for 30 days after cessation of treatment.

The study was completed as planned in 66 patients. Complete healing occurred in 74.2% of patients in the MA group and in 80.6% of patients in the MA + AL group. No difference was found between the two groups with respect to side‐effects.

The combination of AL and MA increases the anti‐leishmanial effects of antimoniate. In this study, it was confirmed that low‐dose MA plus AL is as effective as high‐dose MA in the treatment of cutaneous leishmaniasis caused by L. major.
Probing opioid receptor–ligand interactions by employment of indolizidin‐9‐one amino acid as a constrained Gly2‐Gly3 surrogate in a leucine‐enkephalin mimic
Authors: Gosselin F. , Lubell W.D. , Tourwé D. , Ceusters M. , Meert T. , Heylen L. , Jurzak M.
Published: March 2003

Abstract: The relationship between the conformation and biological activity of Leu‐enkephalin was studied using (2S,6R,8S)‐9‐oxo‐8‐N‐(Boc)amino‐1‐azabicyclo[4.3.0]nonane‐2‐carboxylic acid [(2S,6R,8S)‐1, I9AA] as a constrained Gly2‐Gly3 dipeptide surrogate. [I9AA]2,3‐Leu‐enkephalin 12 was assembled using solid‐phase peptide synthesis on Merrifield resin with TBTU as the coupling reagent. The in vitro assays indicated that [I9AA]2,3‐Leu‐enkephalin 12 exhibited affinities for the µ‐ and δ‐opioid receptors that were three orders of magnitude lower than that of Leu‐enkephalin, as well as partial agonist character for both receptors. In in vivo assays for spinal analgesia, the indolizidinone analog 12 showed significantly enhanced duration of action, indicating an increased metabolic stability. Conformational analysis was performed using NMR and CD spectroscopy. The amide temperature coefficients and 3JNH‐CαH coupling constants for 12 could not support a hydrogen‐bonded β‐turn structure; however, its CD spectrum indicated a turn conformation. Incorporation of indolizidinone amino acid 1 into Leu‐enkephalin thus provided additional support for the importance of a turn conformation for the biological activity of the native peptide.
Cladistic analysis of blue‐green procaryote interrelationships and chloroplast origin based on 16S rRNA oligonucleotide catalogues
Authors: Bremer Birgitta , Bremer K»re
Published: March 2003

Oligonucleotide catalogues from 16S rRNA have been a major source of information for phylogenetic reconstruction among procaryotes. Several large procaryote groups have been analyzed and phylogenies presented. Catalogues are also available for many chloroplasts. The hypotheses of phylogeny are derived mainly from similarity (phenetic) comparisons of the catalogues and the extent of the homoplasy (parallelisms and reversals) involved has not been estimated properly. Although catalogues are currently being superseded by complete sequence data, an evaluation of the strength of catalogue data, and hence of the strength of the extensive phylogenetic hypotheses derived from them, is in order. Cladistic analysis of 16S rRNA oligonucleotide catalogues from three blue‐green procaryotes, Prochloron, and chloroplasts of a red alga, Euglena, a green alga and two flowering plants shows that there is extensive homoplasy in the catalogues and several phylogenetic trees are possible. The corresponding consensus trees indicate that little or nothing can be said about interrelationships and chloroplast origin on the basis of these particular catalogues, except that Prochloron may be more closely related to the blue‐greens than to chloroplasts.