Psoriatic alopecia.

Alopecia and other hair abnormalities occurring in patients with psoriasis were first recognized over four decades ago, yet psoriatic alopecia is not a well-known concept among clinicians. Alopecia may be directly related to the psoriasis itself, and can affect both the scalp and other parts of the body. On the scalp, psoriatic alopecia most commonly affects lesional skin, but may present as a generalized telogen effluvium. In most cases, there is regrowth of hair, but in rare cases it can cause scarring alopecia. Histological findings include features of psoriasis in the interfollicular epithelium, along with perifollicular inflammation and atrophy or loss of the sebaceous glands. Late changes include destruction of the hair follicle, with perifollicular fibrosis and 'naked' hair shafts lying free in the dermis. In addition to the hair loss caused by the psoriasis itself, data from population and genetic studies reveal that patients with psoriasis are at greater risk of developing alopecia areata. Psoriasis treatments may also contribute to hair loss. Application of topical preparations may cause hair loss through friction, and many of the systemic treatments used for psoriasis can also cause hair problems. Treatment with anti-tumour necrosis factor-α agents can precipitate de novo psoriasis and subsequent psoriatic alopecia.

Communicating the risks of handling bats: analysing approaches used by Australian stakeholders in the context of Australian bat lyssavirus.

Australian bat lyssavirus (ABLV) is a member of the Lyssavirus genus of the Rhabdoviridae family and is found in Australian bat species. It is of public health concern because of the rabies-like syndrome it causes in humans, resulting in government health and wildlife agencies using varied communication approaches to inform targeted audiences about zoonotic risks associated with handling bats. Despite these warnings, the number of reports of human-bat interactions remains high. This paper details a survey conducted to analyse the approaches utilised by a range of stakeholders to educate and communicate warnings to their target audiences. The survey focused on identifying the target audiences, communication methods used, along with the message frequency, content, and perceived effectiveness. Analysis of the top three messages delivered by stakeholders revealed that over half were information-focused messages and over a third, instruction-focused. Stakeholders identified the need to balance messaging about bat handling risks with information regarding the vulnerable status of bats and their environmental significance. Whilst the most common and (perceived) effective method of communication was one-on-one discussions, it was also identified to be ineffective for targeting mass audiences leading stakeholders to recognise the need to adapt to more efficient means of communication. The outcomes of this study may be useful to improve risk communication strategies regarding ABLV in Australia.

Selection of tumor-specific epitopes on target antigens for radioimmunotherapy of breast cancer.

Evidence is presented for two different breast epithelial antigens that some epitopes have greater tumor specificity and are more effective targets for radioimmunotherapy than others. The two antigens, which are major components of the human milk fat globule membrane, are breast mucin and a M(r) 46,000 glycoprotein (BA46). Of five monoclonal antibodies (Mc5, Mc1, BrE-1, BrE-2, and BrE-3) against breast mucin, all recognize overlapping amino acid epitopes on the tandem repeat domain. However, each have unique and different tissue and tumor specificities and unique epitope structures on the fully glycosylated breast mucin. In preclinical studies, radioimmunoconjugates of all five monoclonal antibodies inhibit growth of transplantable breast tumors in immunodeficient mice. In human clinical trials, radioiodinated Mc5 was very poor in localizing breast tumor metastases. On the other hand, 111In-labeled BrE-3 imaged almost 90% of breast tumors and showed promise in radioimmunotherapy when labeled with 90Y. The failure of Mc5 in clinical trials may be partly attributed to the high levels of its epitope on circulating mucin compared to the epitope of BrE-3. The Mc5 binding affinity increased significantly with glycosylation, while the BrE-3 epitope was masked by glycosylation. The BA46 glycoprotein is a breast tumor-associated membrane antigen containing an NH2-terminal, epidermal growth factor-like domain into which a cell adhesion sequence (RGD) is inserted and a COOH-terminal domain with homology to the phospholipid binding C1/C2 domain of coagulation factors V and VIII. It promotes cell attachment in an RGD-dependent manner. Monoclonal antibody Mc8, which binds to the C2-like domain, is only moderately effective in experimental radioimmunotherapy, while Mc3, which binds an epitope in the EGF-like RGD domain, was highly effective in destroying breast tumors in nude mice. With 90Y-labeled Mc3, 6 of 7 mice are cured of the tumors. These results indicate that by selecting appropriate monoclonal antibodies, a normal antigen can be used as a target for radioimmunotherapy.

Cloning and sequence analysis of human butyrophilin reveals a potential receptor function.

Human butyrophilin was cloned and sequenced from a human breast cDNA library. The derived amino acid sequence shows 84% sequence identity and identical domain arrangements with the previously reported bovine sequence. Sequence analysis reveals an immunoglobulin constant (IgC) domain that was not previously identified in the bovine sequence. The extracellular domain composition of butyrophilin suggests a cell surface receptor function.

Pentylenetetrazole induced changes in zebrafish behavior, neural activity and c-fos expression.

Rodent seizure models have significantly contributed to our basic understanding of epilepsy. However, medically intractable forms of epilepsy persist and the fundamental mechanisms underlying this disease remain unclear. Here we show that seizures can be elicited in a simple vertebrate system e.g. zebrafish larvae (Danio rerio). Exposure to a common convulsant agent (pentylenetetrazole, PTZ) induced a stereotyped and concentration-dependent sequence of behavioral changes culminating in clonus-like convulsions. Extracellular recordings from fish optic tectum revealed ictal and interictal-like electrographic discharges after application of PTZ, which could be blocked by tetrodotoxin or glutamate receptor antagonists. Epileptiform discharges were suppressed by commonly used antiepileptic drugs, valproate and diazepam, in a concentration-dependent manner. Up-regulation of c-fos expression was also observed in CNS structures of zebrafish exposed to PTZ. Taken together, these results demonstrate that chemically-induced seizures in zebrafish exhibit behavioral, electrographic, and molecular changes that would be expected from a rodent seizure model. Therefore, zebrafish larvae represent a powerful new system to study the underlying basis of seizure generation, epilepsy and epileptogenesis.

Orthotopic models of pediatric brain tumors in zebrafish.

High-throughput screens (HTS) of compound toxicity against cancer cells can identify thousands of potential new drug-leads. But only limited numbers of these compounds can progress to expensive and labor-intensive efficacy studies in mice, creating a 'bottle neck' in the drug development pipeline. Approaches that triage drug-leads for further study are greatly needed. Here we provide an intermediary platform between HTS and mice by adapting mouse models of pediatric brain tumors to grow as orthotopic xenografts in the brains of zebrafish. Freshly isolated mouse ependymoma, glioma and choroid plexus carcinoma cells expressing red fluorescence protein were conditioned to grow at 34 °C. Conditioned tumor cells were then transplanted orthotopically into the brains of zebrafish acclimatized to ambient temperatures of 34 °C. Live in vivo fluorescence imaging identified robust, quantifiable and reproducible brain tumor growth as well as spinal metastasis in zebrafish. All tumor xenografts in zebrafish retained the histological characteristics of the corresponding parent mouse tumor and efficiently recruited fish endothelial cells to form a tumor vasculature. Finally, by treating zebrafish harboring ERBB2-driven gliomas with an appropriate cytotoxic chemotherapy (5-fluorouracil) or tyrosine kinase inhibitor (erlotinib), we show that these models can effectively assess drug efficacy. Our data demonstrate, for the first time, that mouse brain tumors can grow orthotopically in fish and serve as a platform to study drug efficacy. As large cohorts of brain tumor-bearing zebrafish can be generated rapidly and inexpensively, these models may serve as a powerful tool to triage drug-leads from HTS for formal efficacy testing in mice.

Ocular toxocariasis in schoolchildren.

Ocular toxocariasis in humans is typically a unilateral disease caused by second-stage larvae of the Toxocara species. Serological evidence of widespread infection in humans provides little information on clinical disease. There is only a single previous estimate of the prevalence of ocular toxocariasis (from Alabama). The present survey examined the extent of consultant-diagnosed toxocaral eye disease among a population of schoolchildren. More than 120,000 participants were surveyed by questionnaire and follow-up. Two sets of control subjects from the same school and from the same county were compared with persons who had ocular toxocariasis. The prevalence of consultant-diagnosed toxocaral eye disease was 6.6 cases per 100,000 persons when only cases regarded as definite by the consultant ophthalmologist were included. This increased to 9.7 cases per 100,000 persons when both definite and strongly suspected cases were included. Geophagia and a history of convulsion were associated with toxocaral eye disease in both of the case-control studies.

California encephalitis virus causes subacute encephalomyelitis in an adult.

A 24-year-old man from rural Mississippi had a case of California encephalitis (CE) that evolved as a subacute encephalomyelitis. The incidence of CE in adults is low, especially in the southeastern United States, and to our knowledge the clinical profile of symptomatic disease in adults has not been established. The characteristics of CE and St Louis encephalitis, the usual cause of arboviral illness affecting adults in the Southeast, differ.

Use of the Internet by patients and their families to obtain genetics-related information.

OBJECTIVE: To characterize use of the Internet by patients and their families referred to general genetics clinics. PATIENTS AND METHODS: We developed a survey to assess Internet use among patients visiting urban and rural clinics in Colorado and Wyoming. One hundred eighty-nine surveys were distributed to patients and their family members visiting outpatient general genetics clinics in spring 2000. The 8-page anonymous survey instrument asked about use of the Internet to obtain genetics-related information (GRI). All participants were asked whether a physician or health professional had referred them to the Internet for GRI. Subjects who had previously used the Internet to search for GRI were asked to rate whether they considered the GRI they encountered to be accurate, inaccurate, easy to understand, confusing, or trustworthy. RESULTS: One hundred fifty-seven surveys (83%) were returned (52% urban; 48% rural). Ninety (60%) of 149 respondents were at the clinic for a new-patient visit, and 59 (40%) were follow-up visits. All respondents were older than 17 years; 141 (91%) of 155 respondents were the patient's parent or guardian. Seventy-three (47%) of 155 respondents had searched the Internet for GRI prior to their clinic visit. The patients and families themselves initiated the majority of such efforts; only 8 (5%) of 148 respondents had been referred to a site on the World Wide Web by a physician. Interestingly, 136 (92%) of 147 respondents indicated that they would be likely to visit a Web site that was recommended by a geneticist. The most compelling reasons for searching the Internet for GRI were to get information in layperson's terms (60/131 [46%]); to get information about treatment (16/131 [12%]); and to get information about genetic research (16/131 [12%]). Among respondents who reported visiting GRI Web sites, 24 (41%) of 58 agreed that information was confusing or difficult to understand, 35 (53%) of 66 agreed that information was accurate and trustworthy, and 44 (77%) of 57 agreed that using the Internet was a positive experience. CONCLUSION: Internet use among patients referred to general genetics clinics and their family members appears to be widespread. Respondents reported that they found some of the information confusing and questioned its accuracy. Referral to Web sites by physicians was reported rarely, although the majority of respondents said they would visit a Web site recommended by a genetics physician. Further studies are needed to establish the accuracy of Internet information and how best to integrate and/or accommodate the data into the genetics clinic.

Inhibition of Blastomyces dermatitidis by topical lidocaine.

This study was designed to determine if lidocaine inhibited growth of Blastomyces dermatitidis and thereby reduced recovery of the fungus from bronchoscopy specimens. Case records of 36 patients with pulmonary blastomycosis showed that when the fungus was present at microscopy, whether the specimen was sputum or bronchial washings, culture of the bronchoscopic specimen was more frequently negative than the culture of the sputum specimen (p less than .05). In addition, lidocaine was shown to inhibit growth of B dermatitidis in vitro, with the inhibition depending on the concentration of the drug and the duration of exposure (p less than .01). High concentrations of lidocaine for topical anesthesia appear to adversely affect the recovery of B dermatitidis from bronchoscopic specimens.

Cloning and sequence analysis of human breast epithelial antigen BA46 reveals an RGD cell adhesion sequence presented on an epidermal growth factor-like domain.

The BA46 antigen of the human milk fat globule (HMFG) membrane is expressed in human breast carcinomas and has been used successfully as a target for experimental breast cancer radioimmunotherapy. To characterize this antigen further, we obtained the entire cDNA sequence and focused on its possible role in cell adhesion. The derived protein sequence of BA46 encodes a 387-residue precursor composed of a putative signal peptide, an amino-terminal epidermal growth factor (EGF)-like domain containing the cell adhesion tripeptide arginine-glycine-aspartic acid (RGD), and human factor V and factor VIII C1/C2-like domains. The EGF-like domain of BA46 is similar to the calcium-binding EGF-like domains of several coagulation factors, but the BA46 domain lacks a residue required for calcium binding and the coagulation factor domains do not include an RGD sequence. Assuming that all EGF-like domains fold into a similar structure, the RGD-containing sequence in BA46 is inserted between two antiparallel beta strands. This positioning suggests a novel function for the EGF-like domain as a scaffold for RGD presentation.

Lactadherin (formerly BA46), a membrane-associated glycoprotein expressed in human milk and breast carcinomas, promotes Arg-Gly-Asp (RGD)-dependent cell adhesion.

Lactadherin, a major glycoprotein of the human milk fat globule membrane, is abundant in human breast milk and expressed in human breast carcinomas. Previously, we have shown that the mature protein, formerly known as BA46, has three domains: an epidermal growth factor (EGF)-like domain containing an Arg-Gly-Asp (RGD) cell adhesion sequence and C1 and C2 domains similar to those found in coagulation factors V and VIII. An alignment of lactadherin with its bovine (MGP57/53) and murine (MFG-E8) homologs shows that the RGD sequence has been conserved during evolution, suggesting that the RGD sequence is not fortuitous. We demonstrate that lactadherin purified using Triton X-114 phase partitioning promotes RGD-dependent cell attachment of green monkey kidney cells (MA104), mouse fibroblast cells (3T3-L1), and breast carcinoma cells (ELL-G). A lactadherin-specific monoclonal antibody, Mc3, inhibits attachment to purified lactadherin, suggesting that contaminants in the purification are not responsible for binding. In addition, the anti-integrin alpha(v)beta3 monoclonal antibody LM609 inhibits cell attachment of MA104 cells to lactadherin. These results demonstrate that lactadherin promotes RGD-dependent cell adhesion via integrins. Denaturation of lactadherin with heat and reducing conditions diminished cell attachment, suggesting that optimal cell attachment to RGD is dependent on the structural presentation of the sequence.

Antiepithelial cell antibodies do not impair paediatric renal allograft survival but appear to be associated with acute viral infections.

There is a reported association between antiepithelial cell (AEC) antibodies and increased renal allograft loss in paediatric recipients. Our unit experienced a dramatic fall in 1-year graft survival so we undertook a study to determine if AEC antibodies could account for such losses. We also studied healthy children and adults as well as a group of individuals with serologically proven viral infection in an attempt to determine the prevalence and possible aetiology of these antibodies. Sera were screened for AEC antibodies in a microcytotoxicity test using a lung epithelial cell line (A549) as target. The prevalence of these antibodies in our paediatric recipients was similar to that reported elsewhere but we found no correlation between the presence of AEC antibody and allograft loss. Within the control populations, we found the antibody was more prevalent in children than in adults (p < 0.0001). We also found a strong age banding pattern, with antibody being present in 50% of children under 10 years and declining with increasing age, so that by the age of 16 years the seroprevalence was similar to that found in our adults. However, AEC antibody had a significantly higher prevalence in individuals with active viral infection than in our healthy control groups (p = 0.00003). A positive association was noted between rubella and respiratory syncytial virus and AEC antibody presence and a negative association with varicella zoster. We conclude that AEC antibodies do not correlate with increased paediatric renal allograft loss but appear to be linked to certain viral infections.

Lack of association between intraocular melanoma and cutaneous dysplastic nevi.

The occurrence of uveal and cutaneous malignant melanoma and the dysplastic nevus syndrome in the same individual suggests an etiologic relationship among these diseases. Thus, the dysplastic nevus syndrome could be viewed as marking an increased risk of both cutaneous and ocular melanoma. We postulated that if such a relationship exists, patients with both forms of melanoma should have a high prevalence of dysplastic nevi. We examined 44 patients (31 women and 13 men ranging in age from 20 to 80 years) with uveal melanoma for evidence of cutaneous melanoma and dysplastic nevi. We also examined photographs of 46 patients (24 men and 22 women ranging in age from 19 to 67 years) with nonfamilial cutaneous melanoma to determine the prevalence of dysplastic nevi. We found a 4.5% prevalence of dysplastic nevi in patients with uveal melanoma, significantly lower than the 41% prevalence in patients with cutaneous melanoma (two of 44 patients vs 19 of 46 patients). This study indicates that uveal and cutaneous melanoma are not etiologically linked through dysplastic nevi and suggests that patients with uveal melanoma are no more likely to have cutaneous dysplastic nevi than the general population.

Direct monitoring of enzyme reactions using micellar electrokinetic capillary chromatography. Optimisation of drug glucuronide and sulfate conjugate hydrolysis.

This paper demonstrates the use of micellar electrokinetic capillary chromatography (MECC) to monitor enzyme reaction conditions. The hydrolysis reactions of model conjugated substrates (morphine and reduced flunixin glucuronides, napthyl sulfate), by proprietary beta-glucuronidase preparations, were studied under varied experimental conditions. Reactions were carried out in autosampler vials with incubation in a thermostatted CE autosampler tray. MECC was performed using borax buffer (17.5 mM, pH 9.3) modified with sodium dodecyl sulfate (70 mM). Repetitive injections were made from the sample vial throughout the course of the reactions at a frequency of up to 10 h-1. MECC provided a rapid and reproducible assay for the model substrates. Baseline interference from the enzymes prevented measurement of product increase, therefore substrate decrease was measured from the peak areas. Monitoring of reactions in this way has proved valuable in the optimisation of hydrolysis conditions used in sample preparation for drug analysis. beta-Glucuronidase preparations from Helix pomatia were found to give the best performance of those evaluated in terms of deconjugation efficiency.

Determination of phase II drug metabolites in equine urine by micellar electrokinetic capillary chromatography.

Micellar electrokinetic capillary chromatography (MECC) using diode array detection has been investigated for the determination of phase I and phase II metabolites of drugs in biofluids. Methods were optimised for the determination of morphine, morphine-3-glucuronide, morphine-6-glucuronide, normorphine, meclofenamic acid and its metabolites in equine urine. Solid-phase extraction procedure were developed to concentrate and purify the analytes from spiked and post administration urines for MECC analysis. A simple on-line procedure for monitoring the kinetics of hydrolysis of morphine-glucuronide conjugates by beta-glucuronidase was demonstrated.

Rapid detection of meningococci from petechiae in acute meningococcal infection.

In order to evaluate the diagnostic usefulness of Gram-staining films from petechial lesions in suspected meningococcal infection, data from 52 patients with confirmed infection were reviewed. Gram-negative diplococci were found in specimens from skin films in 80% (24/30) patients with petechiae. This is significantly better than results reported for Gram-staining of needle aspirates from petechiae (46%; 12/26). Positive skin films were obtained from 89% (17/19) blood culture negative cases and 85% (17/20) CSF negative cases. In 14 cases meningococcal infection was identified only by skin films. Skin film results were not significantly affected by previous antibiotic. Gram-staining of films from petechial lesions in suspected meningococcal infection is a very rapid and effective investigation. Blood culture, CSF examination and culture, and skin films each identified meningococcal infection not identified by the other two investigations.

Toxocara titres in maternal and cord blood.

Fifty-two pairs of maternal and cord blood samples were examined for evidence of Toxocara canis antibodies. All the mothers in the study delivered normal babies at term. Seventeen (33%) of the mothers had Toxocara antibody titres of 1:50 or greater. No IgM isotype anti-Toxocara antibody was detected in the cord blood samples, evidence that transplacental toxocaral infection had not occurred. In the toxocara antibody-positive group it was found that six of 17 mothers (35%) had previously miscarried compared with three of 35 (8.6%) of the toxocara-negative mothers (P = 0.044).