Multi-locus sequence typing and phylogenetics of Cryptococcus neoformans AD hybrids.

Hybrid AD strains of the human pathogenic Cryptococcus neoformans species complex have been reported from many parts of the world. However, their origin, diversity, and evolution are incompletely understood. In this study, we analyzed 102 AD hybrid strains representing 21 countries on five continents. For each strain, we obtained its mating type and its allelic sequences at each of the seven loci that have been used for genotyping haploid serotypes A and D strains of the species complex by the Cryptococcus research community. Our results showed that most AD hybrids exhibited loss of heterozygosity at one or more of the seven analyzed loci. Phylogenetic and population genetic analyses of the allelic sequences revealed multiple origins of the hybrids within each continent, dating back to one million years ago in Africa and up to the present in other continents. We found evidence for clonal reproduction and long-distance dispersal of these hybrids in nature. Comparisons with the global haploid serotypes A and D strains identified new alleles and new haploid multi-locus genotypes in AD hybrids, consistent with the presence of yet-to-be discovered genetic diversity in haploid populations of this species complex in nature. Together, our results indicate that AD hybrids can be effectively genotyped using the same multi-locus sequencing type approach as that established for serotypes A and D strains. Our comparisons of the AD hybrids among each other as well as with the global haploid serotypes A and D strains revealed novel genetic diversity as well as evidence for multiple origins and dynamic evolution of these hybrids in nature.

Discontinuation Patterns and Cost Avoidance of a Pharmacist-Driven Methicillin-Resistant Staphylococcus aureus Nasal Polymerase Chain Reaction Testing Protocol for De-escalation of Empiric Vancomycin for Suspected Pneumonia.

A pharmacist-driven methicillin-resistant Staphylococcus aureus (MRSA) nasal polymerase chain reaction (PCR)-based testing protocol with a 70% acceptance rate for vancomycin discontinuation within 24 hours of negative results significantly reduced unnecessary vancomycin use with an estimated cost avoidance of $40 per vancomycin course. We found high concordance (141 of 147, 96%) of culture-based versus PCR-based MRSA nasal screening.

Norwich COVID-19 testing initiative pilot: evaluating the feasibility of asymptomatic testing on a university campus.

BACKGROUND: There is a high prevalence of COVID-19 in university-age students, who are returning to campuses. There is little evidence regarding the feasibility of universal, asymptomatic testing to help control outbreaks in this population. This study aimed to pilot mass COVID-19 testing on a university research park, to assess the feasibility and acceptability of scaling up testing to all staff and students. METHODS: This was a cross-sectional feasibility study on a university research park in the East of England. All staff and students (5625) were eligible to participate. All participants were offered four PCR swabs, which they self-administered over two weeks. Outcome measures included uptake, drop-out rate, positivity rates, participant acceptability measures, laboratory processing measures, data collection and management measures. RESULTS: 798 (76%) of 1053 who registered provided at least one swab; 687 (86%) provided all four; 792 (99%) of 798 who submitted at least one swab had all negative results and 6 participants had one inconclusive result. There were no positive results. 458 (57%) of 798 participants responded to a post-testing survey, demonstrating a mean acceptability score of 4.51/5, with five being the most positive. CONCLUSIONS: Repeated self-testing for COVID-19 using PCR is feasible and acceptable to a university population.

Long-term effects of antidepressants on cognition in patients with Alzheimer's disease.

PURPOSE: Approximately 25-40% of patients with Alzheimer's disease (AD) may develop depression. Antidepressants are typically used to treat depression in this population. However, their effect on cognition has been rarely studied and the results are conflicting. In addition, the long-term effects of antidepressants on cognition have not been studied. Therefore, the objective of the study was to evaluate the effects on cognition in patients with AD treated with antidepressants for at least 9 months. METHODS: Data on antidepressant use over a minimum period of 9 months were retrospectively collected for patients with AD receiving cholinesterase inhibitors. Data on cognition were analyzed to compare those taking antidepressant therapy and those not receiving antidepressants. RESULTS: Ninety-nine of 210 patients met our inclusion criteria. Fifty-eight patients were prescribed an antidepressant (e.g. selective serotonin reuptake inhibitors (SSRIs), newer generation antidepressants). Sertraline (mean dose: 82 mg/day) and citalopram (mean dose: 35 mg/day) were the most commonly prescribed antidepressants. The baseline mean Mini Mental State Examination (MMSE) score was 16.32 with an average annual rate of cognitive decline of 2.55 for patients receiving antidepressants compared with 16.59 (P = NS) and 2.27 (P = NS) for those not taking antidepressants. CONCLUSIONS: Our small sample data indicate no differences in baseline MMSE scores and cognitive decline between the two groups, suggesting antidepressants did not contribute significantly to cognitive decline over a utilization period of at least 9 months.

Introducing professional educators into academic medicine: stories of exemplars.

This article describes an oral history project aimed at documenting the history and contributions of the innovation of hiring professional educators in medical schools to improve the education of medical students, residents, and fellows. Six professional educators who spent their careers in medical schools were chosen as Exemplars: Stephen Abrahamson, Ph.D.; Charles Dohner, Ph.D.; Arthur Elstein, Ph.D.; Hilliard Jason, M.D., Ph.D.; Christine McGuire, M.A.; and Frank Stritter, Ph.D. Pairs of senior professional educators currently working in medical schools interviewed the six Exemplars using a standardized protocol. Articles describing each Exemplar appear consecutively in this and subsequent issues of Advances in Health Professions Education. The series culminates with an article that presents the consensus conclusions of the series authors, based on the five study questions that guided the study and interview protocol.

Expression of a transforming gene (E5) of bovine papillomavirus in sarcoids obtained from horses.

OBJECTIVE: To determine expression of a transforming gene (E5) of bovine papillomavirus in sarcoids, other tumors, and normal skin samples collected from horses with and without sarcoids. SAMPLE POPULATION: 23 sarcoids and 6 samples of normal skin obtained from 16 horses with sarcoids, 2 samples of normal skin and 2 papillomas obtained from horses without sarcoids, and 1 papilloma obtained from a cow. PROCEDURE: Protein was extracted from tissue samples collected from horses and incubated with agarose beads covalently coupled to Staphylococcus aureus protein A and an anti-E5 polyclonal antibody. Following incubation, proteins were eluted from the beads and electrophoresed on a 14% polyacrylamide gel and transferred to a polyvinylidene difluoride membrane. The E5 protein was detected by use of western blot analysis, using a chemiluminescence detection system. RESULTS: All 23 sarcoids had positive results for expression of E5 protein. Quantity of viral protein appeared to vary among sarcoids. All other tissues examined had negative results for E5 protein. Highest expression for E5 protein was observed in biologically aggressive fibroblastic variants of sarcoids, compared with expression in quiescent tumors. CONCLUSIONS AND CLINICAL RELEVANCE: This study documented that activation and expression of the E5 gene is evident in sarcoids obtained from horses. These data support the conclusion that infection with bovine papillomavirus is important in the initiation or progression of sarcoids in horses. Treatment strategies designed to increase immune recognition of virally infected cells are warranted.

Bovine papillomavirus DNA in neoplastic and nonneoplastic tissues obtained from horses with and without sarcoids in the western United States.

OBJECTIVE: To determine the incidence of bovine papillomavirus (BPV) type 1 or 2 in sarcoids and other samples of cutaneous tissues collected from horses in the western United States. ANIMALS: 55 horses with sarcoids and 12 horses without sarcoids. PROCEDURE: Tissue samples (tumor and normal skin from horses with sarcoids and normal skin, papillomas, and nonsarcoid cutaneous neoplasms from horses without sarcoids) were collected. Tissue samples were analyzed for BPV-1 or -2 DNA, using a polymerase chain reaction (PCR) and restriction fragment length polymorphism. The PCR products from 7 sarcoid-affected horses were sequenced to evaluate percentage homology with expected sequences for BPV-1 or-2. RESULTS: Most (94/96, 98%) sarcoids contained BPV DNA. Sixty-two percent of the tumors examined had restriction enzyme patterns consistent with BPV-2. Thirty-one of 49 (63%) samples of normal skin obtained from horses with sarcoids contained BPV DNA. All samples subsequently sequenced had 100% homology with the expected sequences for the specific viral type. All tissues from healthy horses, nonsarcoid neoplasms, and papillomas were negative for BPV DNA. CONCLUSIONS AND CLINICAL RELEVANCE: Bovine papillomaviral DNA was detected in essentially all sarcoids examined. There appears to be regional variation in the prevalence of viral types in these tumors. The fact that we detected viral DNA in normal skin samples from horses with sarcoids suggests the possibility of a latent viral phase. Viral latency may be 1 explanation for the high rate of recurrence following surgical excision of sarcoids.

Necrobiosis lipoidica associated with Köbner's phenomenon in a patient with diabetes.

Necrobiosis lipoidica (NL) is a granulomatous disease that usually presents on the lower extremities of patients with diabetes mellitus. We present a rare case of NL köbnerizing in a surgical scar on the upper extremity of a patient with diabetes. NL is generally refractory to treatment.

Primitive neuroectodermal tumors of the biliary and gastrointestinal tracts: clinicopathologic and molecular diagnostic study of two cases.

Primitive neuroectodermal tumor (PNET) is a prototypic malignant small round cell tumor of childhood that is characterized in most cases by t(11;22) resulting in an EWS-FLI1 gene fusion. Once thought to be uncommon, PNET now accounts for almost 20% of malignant soft tissue tumors in children. Increased recognition of PNET is partly due to advances in immunohistochemistry and molecular diagnostics, which have led to the identification of the tumor in non-classical sites. We report the clinical, histologic, immunohistochemical, and molecular findings of two visceral PNETs of the digestive system--one involving the small intestine and the other involving the hepatic duct. Histologically, each tumor was composed of malignant small cells growing in sheets, nests, and lobules; the tumor cells of both cases showed characteristic immunoreactivity for vimentin and O13 (CD99). Reverse transcription-polymerase chain reaction (RT-PCR) analysis for t(11;22) using nested primers was performed with RNA extracted from paraffin-embedded, formalin-fixed tissue and demonstrated an EWS exon 7 to FLI1 exon 5 fusion in both cases, confirmed by Southern blot hybridization and DNA sequence analysis. These results illustrate the expanded clinicopathologic profile of PNET, and demonstrate that visceral PNETs, despite their unusual sites of presentation, maintain the characteristic immunohistochemical and genetic features of PNETs at more conventional sites.

Utility of rush paraffin-embedded tangential sections in the management of cutaneous neoplasms.

BACKGROUND: Mohs micrographic surgery (MMS) modified by the use of tangential, formalin-fixed, paraffin-embedded histologic specimens is advantageous in treating selected skin neoplasms. OBJECTIVE: To review the use of our experience with a modification of MMS to treat lentigo maligna melanoma (LMM), lentigo maligna (LM) and other melanoma in situ (MIS) lesions, dermatofibrosarcoma protuberans (DFSP), atypical fibroxanthoma (AFX), and angiosarcoma. METHODS: Our experience utilizing a modification of MMS in the treatment of 77 patients with LM or other MIS, 23 patients with LMM, 11 patients with DFSP, 1 patient with AFX, and 1 patient with angiosarcoma was reviewed. Length of follow-up and rate of recurrence were examined. A literature review of this pertinent modification of the Mohs technique was performed. RESULTS: One hundred fourteen patients underwent MMS for melanocytic (LM, MIS, LMM), spindle cell (DFSP, AFX), and vascular malignant neoplasms. One patient developed locally recurrent LM and one patient with LMM developed satellite metastasis. Regional lymph node metastasis occurred in one patient with LMM and in a patient with angiosarcoma. CONCLUSION: The use of Mohs micrographic surgery in conjunction with rush formalin-fixed, paraffin-embedded tangential histologic sections provides the accuracy and tissue conservation of the Mohs procedure while ensuring more confident interpretation of histology in cases of lentigo maligna, lentigo maligna melanoma, dermatofibrosarcoma protuberans, atypical fibroxanthoma, and angiosarcoma.

Teaching faculty to conduct problem-based learning.

PURPOSE: This article is aimed at those who undertake a transition to problem-based learning (PBL) and focuses on 3 questions that seem most pertinent to the effort: (a) what is known from past research about training faculty in the skills of PBL?, (b) what skills are important to teach faculty and how does one teach them?, and (c) what options are available for training faculty in PBL? SUMMARY: The success of any PBL curricular initiative requires the assistance of faculty skilled in PBL. The development of faculty with such skills must be a primary and ongoing concern of programs or schools launching such efforts. This article describes the research associated with training faculty to conduct PBL, the skills to be taught, and the training options available. CONCLUSIONS: Few studies document the impact of PBL faculty development strategies. Many faculty experience a difficult transition when retraining to PBL. Training faculty for PBL is often taken to mean training them to be tutors, but there are more skills involved in implementing PBL. Finally, there is an implied sequence to training faculty to implement PBL.

Cutaneous melanoma with myxoid features: twelve cases with differential diagnosis.

Substantial myxoid change can occur in malignant melanoma, but its importance in primary disease has not been systematically evaluated. This report describes the clinical, microscopic, histochemical, and immunohistochemical findings in 12 patients with primary cutaneous malignant melanoma with myxoid features. The tumors presented as solitary lesions situated on the limbs (six lesions), trunk (four lesions), and head and neck (two lesions). The patients included six women and six men, whose ages ranged from 26 to 95 years, with a mean of 63 years. Breslow thickness varied from 0.48 mm to more than 12 mm, with a mean of more than 3.2 mm. Clinical follow-up for an average of 22 months showed one local recurrence, but no evidence of metastases yet. In all cases, there was a combination of myxoid and nonmyxoid areas. A minimum of 15% myxoid cross-sectional area was required for inclusion in the study, and up to 80% was observed. The pale blue mucin identified on hematoxylin and eosin staining was sensitive to hyaluronidase and positive for alcian blue in the 10 cases stained. Immunohistochemical staining was positive for S-100 in all 9 cases stained, positive for HMB-45 in 9 (90%) of 10, and negative for cytokeratin in all 9 cases in which myxoid melanoma remained in the block after previous sections. The presence of myxoid stroma did not define a biologically significant subgroup of melanoma. Only in cases with extensive (>50%) myxoid stromal effacement of the melanoma was there a major diagnostic hurdle. The diagnosis of primary cutaneous melanoma with myxoid features was seldom as problematic as metastatic myxoid melanoma. Positive S-100 stains, negative cytokeratin immunohistochemical stains, and hyaluronidase-sensitive alcian blue staining assisted in the diagnosis of this entity.

Developing occupational and environmental medicine curricula for primary care residents: project EPOCH-Envi. Educating Physicians in OCupational Health and the Environment.

To help primary care residency programs develop or improve residency curricula in occupational and environmental medicine, the National Institute for Occupational Safety and Health launched a train-the-trainer initiative. This project was called EPOCH-Envi (Educating Physicians in OCcupational Health and the Environment). From 1990 to 1996, 46 2-day curriculum development workshops were held. These featured (1) guidelines on how to plan, implement, and evaluate a curriculum, (2) continuing education on occupational illnesses and injuries, (3) a worksite or environmental site visit, and (4) information resources. A total of 435 faculty from 305 residency programs participated, representing 42.5% of the family practice residencies and 24.9% of the internal medicine residencies in the United States. A survey conducted among attendees (60.4% response rate) 17 months after their workshop revealed that 65.6% of respondents had added lectures on occupational and environmental topics to the residency curriculum. Other curriculum improvements were also made. Primary care physicians manage most patients with occupational and environmental health problems or concerns. Providing technical assistance specifically designed to support occupational and environmental health education in primary care residencies can have a positive impact on curriculum content.

Diagnosis: erythema nodosum or not?

Erythema nodosum is the final common pathway to a myriad of insults and is thought to be a hypersensitivity reaction centered in the subcutis. To recognize the histological spectrum of erythema nodosum, one must be aware of the morphologic chronology of the disease (early, fully developed, late) and its clinical variants (erythema nodosum migrans). This article reviews the range of changes that can be seen in this prototype of a septal panniculitis and describes the diversity that may be accepted in the diagnosis. Differential diagnoses at each stage of disease development are discussed. The criteria elaborated should assist the pathologist in answering the clinician's query, "Erythema nodosum, or not?"

Peer and self assessment during problem-based tutorials.

BACKGROUND: Peer and self assessment may contribute a unique and insightful perspective to a students' performance. This study investigates the association between self, peer, and faculty evaluations in the intimate setting of a problem-based tutorial group. METHODS: Third-year medical students participating in the required third-year surgical clerkship during the 1996-97 academic year (n = 154) were randomly assigned to problem-based learning groups and completed self and peer evaluations at the end of the last tutorial. These evaluations were compared with expert tutor ratings using Pearson correlation coefficients. RESULTS: A moderate correlation was found between peer and tutor ratings. There was very little correlation between self and tutor ratings. CONCLUSIONS: The results of this study suggest that peer and self ratings in the setting of a tutorial group may provide additional valuable information regarding medical student performance during a surgery clerkship.

Apocrine poroma: a distinctive case in a patient with nevoid basal cell carcinoma syndrome.

Traditionally, poromas have been classified as eccrine neoplasms, but several recent reports of poroid tumors with sebaceous, follicular, and apocrine differentiation have challenged this idea. In support of alternative differentiation, a case of an "apocrine" poroma is reported in a 19-year-old man with the nevoid basal cell carcinoma syndrome. A papule on the right cheek, thought clinically to be a basal cell carcinoma, was excised. Anastomosing lobules of small uniform basaloid (poroid) cells formed small ductular structures lined by eosinophilic cuticles and extended into the superficial reticular dermis. The neoplasm originated from follicular infundibula and was surrounded by a myxoid stroma. Focally, primitive hair bulb and papillae differentiation was present, and some of the ducts were lined by cells suggesting decapitation secretion. The histologic pattern and the common embryologic origin of the folliculosebaceous-apocrine unit support apocrine differentiation of this tumor. The association with the nevoid basal carcinoma syndrome appears to be unique. This case, in addition, demonstrates overlapping features with the infundibulocystic type of basal cell carcinoma commonly seen in the basal cell nevus syndrome.