MYC amplification in angiosarcomas arising in the setting of chronic lymphedema of morbid obesity.

BACKGROUND: Angiosarcoma is a malignancy of vascular endothelial cells which may arise secondarily as a complication of lymphedema, including chronic lymphedema of morbid obesity. Amplifications in MYC are frequently present in secondary angiosarcoma (arising in irradiated sites and chronic lymphedema) and less frequently in primary cutaneous angiosarcoma. OBJECTIVE: To describe the presence of MYC amplifications in two cases of cutaneous angiosarcoma secondary to chronic lymphedema of morbid obesity. METHODS: This study is a case series of two patients with cutaneous angiosarcoma. Clinical data was retrieved from the medical records. Histopathological analysis of the biopsy specimens was performed, including immunohistochemistry, along with fluorescence in situ hybridization. RESULTS: Angiosarcoma arose in the setting of massive chronic lymphedema complicating morbid obesity without other predisposing risk factors. Both cases exhibited epithelioid cell morphology and high-level MYC amplification. CONCLUSION: We report MYC amplification in two cases of angiosarcoma arising in massive chronic lymphedema of morbid obesity.

Infectious crystalline keratopathy in dogs and cats: clinical, in vivo confocal microscopic, histopathologic, and microbiologic features of eight cases.

OBJECTIVE: To describe clinical, in vivo confocal microscopic, histopathologic, and microbiologic features of canine and feline cases of infectious crystalline keratopathy (ICK). ANIMALS STUDIED: Six dogs and two cats with naturally acquired ICK. PROCEDURES: Medical records of dogs and cats with a clinical diagnosis of ICK were reviewed. Signalment, medical history, clinical findings, and diagnostic evaluations were retrieved, including corneal cytology, histopathology, in vivo confocal microscopy, and microbiology results. RESULTS: All animals presented with fine, needle-like, and branching white crystalline anterior stromal opacities emanating from corneal facets or corneal epithelial defects. Mild conjunctival hyperemia and anterior uveitis were frequently present. Concurrent ocular and systemic diseases were common, including keratoconjunctivitis sicca, corneal sequestrum, diabetes mellitus, hyperadrenocorticism, and malignant neoplasia. Bacteria, with minimal or absent leukocytes, were identified by cytology and histopathology. Histopathologically, the crystalline corneal opacities corresponded with dense accumulations of bacteria present in the interlamellar stromal spaces and forming cord-like projections within the stroma. In vivo confocal microscopy demonstrated deposits of reflective crystalline or amorphous structures within the stroma with a paucity of associated inflammatory changes. The most frequently cultured bacteria were alpha-hemolytic Streptococcus and Staphylococcus species. Resolution of clinical lesions was achieved in most cases with long-term medical or surgical therapy; however, the initiation of medical treatment was associated with an acute, dramatic onset of severe keratitis and anterior uveitis in some animals. CONCLUSIONS: Infectious crystalline keratopathy in dogs and cats shares many features with this condition in human patients. Prolonged medical therapy, or surgical intervention, is required for resolution.

Phakomatous choristoma in a 10-week-old boy: a case report and review of the literature.

Phakomatous choristoma (PC) is a rare benign congenital lesion of lenticular anlage. It presents in young patients as a firm subcutaneous mass in the medial eyelid or orbit and may raise clinical concern for neoplasms such as rhabdomyosarcoma, but its histopathology is distinct, consisting of dense collagenous stroma and eosinophilic cuboidal epithelial cells forming nests, tubules, cords, or pseudoglands. We present a case of PC in a 10-week-old boy to illustrate the unique clinical, histopathologic, and immunophenotypic features of this condition and to reaffirm that familiarity with this rare entity aids accurate diagnosis.

Sorcin modulates mitochondrial Ca(2+) handling and reduces apoptosis in neonatal rat cardiac myocytes.

Sorcin localizes in cellular membranes and has been demonstrated to modulate cytosolic Ca(2+) handling in cardiac myocytes. Sorcin also localizes in mitochondria; however, the effect of sorcin on mitochondrial Ca(2+) handling is unknown. Using mitochondrial pericam, we measured mitochondrial Ca(2+) concentration and fluxes in intact neonatal cardiac myocytes overexpressing sorcin. Our results showed that sorcin increases basal and caffeine-stimulated mitochondrial Ca(2+) concentration. This effect was associated with faster Ca(2+) uptake and release. The effect of sorcin was specific for mitochondria, since similar results were obtained with digitonin-permeabilized cells, where cytosolic Ca(2+) flux was disrupted. Furthermore, mitochondria of cardiac myocytes in which sorcin was overexpressed were more Ca(2+)-tolerant. Experiments analyzing apoptotic signaling demonstrated that sorcin prevented 2-deoxyglucose-induced cytochrome c release. Furthermore, sorcin prevented hyperglycemia-induced cytochrome c release and caspase activation. In contrast, antisense sorcin induced caspase-3 activation. Thus, sorcin antiapoptotic properties may be due to modulation of mitochondrial Ca(2+) handling in cardiac myocytes.

Toxic epidermal necrolysis: Part I. Introduction, history, classification, clinical features, systemic manifestations, etiology, and immunopathogenesis.

Toxic epidermal necrolysis is a life-threatening, typically drug-induced mucocutaneous disease. It is clinically characterized as a widespread sloughing of the skin and mucosa, including both external and internal surfaces. Histologically, the denuded areas show full thickness epidermal necrosis. The pathogenic mechanism involves antigenic moiety/metabolite, peptide-induced T cell activation, leading to keratinocyte apoptosis through soluble Fas ligand, perforin/granzyme B, tumor necrosis factor-alfa, and nitric oxide. Recent studies have implicated granulysin in toxic epidermal necrolysis apoptosis and have suggested that it may be the pivotal mediator of keratinocyte death.

Toxic epidermal necrolysis: Part II. Prognosis, sequelae, diagnosis, differential diagnosis, prevention, and treatment.

Toxic epidermal necrolysis (TEN) is a life-threatening, typically drug-induced, mucocutaneous disease. TEN has a high mortality rate, making early diagnosis and treatment of paramount importance. New but experimental diagnostic tools that measure serum granulysin and high-mobility group protein B1 (HMGB1) offer the potential to differentiate early TEN from other, less serious drug reactions, but these tests have not been validated and are not readily available. The mainstay of treatment for TEN involves discontinuation of the offending drug, specialized care in an intensive care unit or burn center, and supportive therapy. Pharmacogenetic studies have clearly established a link between human leukocyte antigen allotype and TEN. Human leukocyte antigen testing should be performed on patients of East Asian descent before the initiation of carbamezapine and on all patients before the initiation of abacavir. The effectiveness of systemic steroids, intravenous immunoglobulins, plasmapheresis, cyclosporine, biologics, and other agents is uncertain.

The potential risk associated with foodborne pathogens in a watershed: Escherichia coli O157:H7 in dairy cattle.

We carried out an investigation to determine the occurrence of Escherichia coli O157:H7 in dairy herds in the Delaware County watershed and to identify the factors that play a role in the likelihood of presence of this organism among animals on these farms. The pathogen poses risk of environmental degradation and health to the inhabitants. A total of 2162 fecal samples were collected per rectum from a representative sample of cattle on 27 dairy farms. The samples were investigated for the presence of E. coli O157:H by initially enriching using a bacteriological media and detection of the pathogen using real-time polymerase chain reaction technique. Escherichia coli O157:H7 was detected in 74% of the herds in the target population and in 3.7% of samples collected. An additional 54 animals were identified that were infected with O157 non-H7 strains of E. coli among 15 farms. Several putative risk factors were associated with the detection of the pathogen on the enrolled farms included age, housing calves indoors, group housing for calves, housing calves in the calf barn, presence of dogs on the farm, and housing post-weaned calves in a cow barn or heifer barn versus a greenhouse. In conclusion, E. coli O157:H7 was present on the dairy farms of Delaware County and may pose a threat to the people that live and work there. The risk associated with the detection of this pathogen could be reduced by adjusting management factors that were identified in this study.

Content and construct validation of a robotic surgery curriculum using an electromagnetic instrument tracker.

PURPOSE: Rapid adoption of robot-assisted surgery has outpaced our ability to train novice roboticists. Objective metrics are required to adequately assess robotic surgical skills and yet surrogates for proficiency, such as economy of motion and tool path metrics, are not readily accessible directly from the da Vinci® robot system. The trakSTAR™ Tool Tip Tracker is a widely available, cost-effective electromagnetic position sensing mechanism by which objective proficiency metrics can be quantified. We validated a robotic surgery curriculum using the trakSTAR device to objectively capture robotic task proficiency metrics. MATERIALS AND METHODS: Through an institutional review board approved study 10 subjects were recruited from 2 surgical experience groups (novice and experienced). All subjects completed 3 technical skills modules, including block transfer, intracorporeal suturing/knot tying (fundamentals of laparoscopic surgery) and ring tower transfer, using the da Vinci robot with the trakSTAR device affixed to the robotic instruments. Recorded objective metrics included task time and path length, which were used to calculate economy of motion. Student t test statistics were performed using STATA®. RESULTS: The novice and experienced groups consisted of 5 subjects each. The experienced group outperformed the novice group in all 3 tasks. Experienced surgeons described the simulator platform as useful for training and agreed with incorporating it into a residency curriculum. CONCLUSIONS: Robotic surgery curricula can be validated by an off-the-shelf instrument tracking system. This platform allows surgical educators to objectively assess trainees and may provide credentialing offices with a means of objectively assessing any surgical staff member seeking robotic surgery privileges at an institution.

Premature hair graying.

Hair pigmentation and graying are important topics for the understanding of the physiology of aging; the differentiation of stem cells; and the mechanisms underlying disease processes such as progeroid syndromes, vitiligo, and hypothyroidism. Although hair graying, or canities, is a common process occurring in people as they age, an unknown percentage of individuals experience premature graying from familial inheritance or pathologic conditions. We review the physiology of hair pigmentation and the mechanism underlying physiologic graying, and we explore the etiology of pathologic causes of premature graying, pathologies associated with premature graying, and the limited available treatment options for hair graying.

Sometimes it takes darkness to see the light: pitfalls in the interpretation of cell proliferation markers (Ki-67 and PCNA).

The degree of cell proliferation in a tumor is often associated with metastatic risk and mortality. Proliferating cell nuclear antigen (PCNA) and Ki-67 are proliferation markers that can be used to assess malignant potential in cutaneous lesions and pathological cell proliferation in psoriasis. These markers are elevated during periods of cell proliferation; however, they are also upregulated following UV irradiation. This upregulation may be problematic, as many skin lesions are subject to sun exposure in an everyday setting.

High-content analysis and Kinetic Image Cytometry identify toxicity and epigenetic effects of HIV antiretrovirals on human iPSC-neurons and primary neural precursor cells.

INTRODUCTION: Despite viral suppression due to combination antiretroviral therapy (cART), HIV-associated neurocognitive disorders (HAND) continue to affect half of people with HIV, suggesting that certain antiretrovirals (ARVs) may contribute to HAND. METHODS: We examined the effects of nucleoside/nucleotide reverse transcriptase inhibitors tenofovir disoproxil fumarate (TDF) and emtricitabine (FTC) and the integrase inhibitors dolutegravir (DTG) and elvitegravir (EVG) on viability, structure, and function of glutamatergic neurons (a subtype of CNS neuron involved in cognition) derived from human induced pluripotent stem cells (hiPSC-neurons), and primary human neural precursor cells (hNPCs), which are responsible for neurogenesis. RESULTS: Using automated digital microscopy and image analysis (high content analysis, HCA), we found that DTG, EVG, and TDF decreased hiPSC-neuron viability, neurites, and synapses after 7 days of treatment. Analysis of hiPSC-neuron calcium activity using Kinetic Image Cytometry (KIC) demonstrated that DTG and EVG also decreased the frequency and magnitude of intracellular calcium transients. Longer ARV exposures and simultaneous exposure to multiple ARVs increased the magnitude of these neurotoxic effects. Using the Microscopic Imaging of Epigenetic Landscapes (MIEL) assay, we found that TDF decreased hNPC viability and changed the distribution of histone modifications that regulate chromatin packing, suggesting that TDF may reduce neuroprogenitor pools important for CNS development and maintenance of cognition in adults. CONCLUSION: This study establishes human preclinical assays that can screen potential ARVs for CNS toxicity to develop safer cART regimens and HAND therapeutics.

Adolescent androgenic alopecia.

Adolescent androgenic alopecia is pattern hair loss occurring in boys and girls younger than 18 years, whereas early-onset androgenic alopecia refers to pattern hair loss before 35 years of age. A number of studies published in the last decade have helped to elucidate the prevalence of adolescent androgenic alopecia, have clarified the genetic as well as physiologic mechanisms underlying hair loss, and have revealed the associated psychologic and systemic morbidities. This article provides an overview of the pathophysiology, diagnosis, and treatment of adolescent androgenic alopecia.

Molecular identification of veterinary yeast isolates by use of sequence-based analysis of the D1/D2 region of the large ribosomal subunit.

Conventional methods of yeast identification are often time-consuming and difficult; however, recent studies of sequence-based identification methods have shown promise. Additionally, little is known about the diversity of yeasts identified from various animal species in veterinary diagnostic laboratories. Therefore, in this study, we examined three methods of identification by using 109 yeast samples isolated during a 1-year period from veterinary clinical samples. Comparison of the three methods-traditional substrate assimilation, fatty acid profile analysis, and sequence-based analysis of the region spanning the D1 and D2 regions (D1/D2) of the large ribosomal subunit-showed that sequence analysis provided the highest percent identification among the three. Sequence analysis identified 87% of isolates to the species level, whereas substrate assimilation and fatty acid profile analysis identified only 54% and 47%, respectively. Less-stringent criteria for identification increased the percentage of isolates identified to 98% for sequence analysis, 62% for substrate assimilation, and 55% for fatty acid profile analysis. We also found that sequence analysis of the internal transcribed spacer 2 (ITS2) region provided further identification for 36% of yeast not identified to the species level by D1/D2 sequence analysis. Additionally, we identified a large variety of yeast from animal sources, with at least 30 different species among the isolates tested, and with the majority not belonging to the common Candida spp., such as C. albicans, C. glabrata, C. tropicalis, and the C. parapsilosis group. Thus, we determined that sequence analysis of the D1/D2 region was the best method for identification of the variety of yeasts found in a veterinary population.

The effect of clinical outbreaks of salmonellosis on the prevalence of fecal Salmonella shedding among dairy cattle in New York.

The objective of this study was to determine if the within-herd prevalence of fecal Salmonella shedding is higher in dairy herds with clinical outbreaks of disease, as compared to herds with subclinical infections only. Data were collected prospectively from dairy herds throughout New York that had at least 150 lactating cows and that received clinical service from participating veterinarians. After enrollment, Salmonella surveillance consisted of both environmental screening and disease monitoring within the herd. Herds positive by either environmental or fecal culture were sampled during three visits to estimate the within-herd prevalence of Salmonella. We characterized isolates by serovar and antimicrobial resistance pattern. Among 57 enrolled herds, 44 (77%) yielded Salmonella-positive samples during the study period; 27 (61%) of the positive herds had Salmonella isolated from environmental samples only, and 17 (39%) had one or more laboratory-confirmed clinical cases. The within-herd prevalence of fecal Salmonella shedding ranged from 0 to 53%. Salmonella Cerro was the predominant serovar, accounting for 56% of all isolates. Antimicrobial resistance ranged from zero to nine drugs, and 14 (32%) of the positive farms generated multidrug-resistant isolates. Herds with laboratory-confirmed clinical cases had a higher prevalence of fecal Salmonella shedding than herds that only generated positive environmental samples, as estimated by a Poisson regression model (prevalence ratio, 2.7; p = 0.01). An association between dairy herd outbreaks of salmonellosis and a higher prevalence of asymptomatic shedding should help guide strategies for reducing the public health threat of Salmonella, as the ability to recognize high-risk herds by clinical laboratory submissions presents an obvious opportunity to maximize food safety at the preharvest level. This is in contrast with other foodborne zoonotic pathogens, such as Campylobacter jejuni and Escherichia coli O157:H7, which occur widely in adult cattle without accompanying clinical disease.

Pulsed-field gel electrophoresis diversity of human and bovine clinical Salmonella isolates.

Pulsed-field gel electrophoresis (PFGE) characterization of 335 temporally and spatially matched clinical, bovine, and human Salmonella enterica subsp. enterica isolates revealed 167 XbaI PFGE patterns. These isolates were previously classified into 51 serotypes and 73 sequence types, as determined by multilocus sequence typing. Discriminatory power of PFGE (Simpson's index, D = 0.991) was considerably higher than that of multilocus sequence typing (D = 0.920) or serotyping (D = 0.913). Although 128 PFGE types each only represented a single isolate, 8 PFGE types represented >4 isolates, including (i) three serotype Enteritidis and Heidelberg patterns that were only identified among human isolates, (ii) two PFGE patterns (each representing serotypes Bardo and Newport) that were significantly more common among bovine isolates as compared with human isolates; (iii) two PFGE types that each includes two serotypes (4,5,12:i:- and Typhimurium; Thompson and 1,7:-:1,5); and (iv) one PFGE type that includes eight Typhimurium isolates from humans and cattle. Characterization of isolates collected over multiple farm visits indicated that given specific PFGE types persisted over time on 11 farms. On an additional seven farms, isolates with a given sequence type represented multiple PFGE type, which typically only differed by <3 bands, suggesting PFGE type diversification during strain persistence. Sixteen PFGE types were isolated from 2 or more farms, including two widely distributed serotype Newport-associated PFGE types each found on 10 farms. In six instances two or three human isolates collected in the same county in the same or consecutive months represented the same subtypes, suggesting small human case clusters. PFGE-based characterization and surveillance of human and animal isolates can provide improved understanding of Salmonella diversity and epidemiology, including identification of possible host-associated and common, widely distributed PFGE types.

Multilocus variable-number tandem-repeat method for typing Salmonella enterica serovar Newport.

In recent years, the proportion of Salmonella enterica infections represented by S. enterica serovar Newport has increased markedly among humans and animals. Multilocus variable-number tandem-repeat analysis (MLVA) has proven to be useful in discriminating other highly clonal Salmonella serovars. Here, we report on the development of a highly discriminatory MLVA for Salmonella serovar Newport.

Identification of potential on-farm sources of Listeria monocytogenes in herds of dairy cattle.

OBJECTIVE: To elucidate the ecology of Listeria monocytogenes on dairy cattle farms by determining the prevalence of the organism in various samples. SAMPLE POPULATION: Dairy cattle operations in central New York State. PROCEDURES: A repeated cross-sectional study design was used. Various samples were obtained from cattle (feces, composite udder milk, and udders), their environment (silage, feed bunks, water troughs, and floor bedding), inline milk filters, and bulk tank milk from 50 dairy farms. Samples were tested for L monocytogenes by use of a PCR assay with 2 steps of bacterial enrichment. Data were analyzed with mixed-effect logistic regression to control for the potential clustering of L monocytogenes on particular farms. RESULTS: L monocytogenes was detected in composite milk, udder swab samples, and fecal samples at prevalences of 13%, 19%, and 43%, respectively. There was no significant clustering of the pathogen by farm. Listeria monocytogenes was more common in samples obtained from cattle and the environment during winter and summer versus the fall. The prevalence of L monocytogenes was twice as high in samples obtained from feed bunks, water troughs, and bedding, compared with that in samples obtained from silage (65%, 66%, 55%, and 30%, respectively). CONCLUSIONS AND CLINICAL RELEVANCE: L monocytogenes was more prevalent in samples obtained from dairy cattle and their environment than in milk samples. Strategies to control the pathogen in dairy operations should focus on cow hygiene and sanitary milk harvesting on the farm.

Fecal shedding of Salmonella spp among cattle admitted to a veterinary medical teaching hospital.

OBJECTIVE- To estimate the prevalence of fecal shedding of Salmonella spp among bovine patients at a veterinary teaching hospital, to identify risk factors for fecal shedding of Salmonella organisms, and to characterize the serotypes. DESIGN- Retrospective cohort study. SAMPLE POPULATION- 5,398 hospitalized cattle. PROCEDURES- Data were collected for all cattle admitted during an 11-year period. Fecal shedding of Salmonella spp was determined by means of standard bacteriologic culture. Multivariable logistic regression models were used to identify risk factors for shedding of Salmonella spp among patients. RESULTS- The prevalence of Salmonella shedding among clinical suspects was 6.5% (50/768), whereas that among nonsuspects tested through routine surveillance was 2.5% (50/2,020). Among clinical suspect calves, fecal shedding of Salmonella spp was more likely for those admitted in the fall (odds ratio [OR], 5.9), those with septicemia (OR, 3.3), or those with an umbilical hernia (OR, 8.6). Among clinical suspect adult cattle, those with enteritis (OR, 9.9) or metritis (OR, 5.2) were more likely to be shedding Salmonella spp. Among nonsuspect cattle, none of the variables were significant predictors of shedding status. Twenty-one serotypes were detected during the study period, with the most common being Salmonella enterica serotypes Typhimurium (33%), Newport (23%), and Agona (12%). CONCLUSIONS AND CLINICAL RELEVANCE- Seasonal and disease risk factors for fecal shedding of Salmonella spp were evident among clinical suspect cattle admitted to a veterinary teaching hospital. In contrast, lack of significant associations among nonsuspect cattle would suggest that targeted screening within this population is not warranted.

Fecal shedding of, antimicrobial resistance in, and serologic response to Salmonella Typhimurium in dairy calves.

OBJECTIVE: To determine the duration of fecal shedding of and serologic response to Salmonella spp after natural infection in dairy calves and characterize Salmonella organisms recovered from these herds. DESIGN: Longitudinal study. ANIMALS: Calves from 2 dairy herds (A and B) in the northeast United States that were identified at the beginning of a Salmonella outbreak. PROCEDURES: Fecal samples were collected twice per week (herd A) or once per week (herd B); blood samples were collected for serologic testing once per week in both herds. Bacteriologic culture of fecal samples was performed, and Salmonella isolates were characterized by serotype, pulsed-field gel electrophoresis (PFGE) pattern, and antimicrobial resistance profile. RESULTS: All Salmonella isolates from herd A were serovar Typhimurium var Copenhagen, had the same PFGE pattern, and were resistant to at least 9 antimicrobials. All isolates from herd B were Salmonella Typhimurium, represented 2 PFGE patterns, and were susceptible to all antimicrobials evaluated. The estimated duration of fecal shedding was 14 days in herd A and 9 days in herd B. Few calves were seropositive for antibody against Salmonella lipopolysaccharide within the first week after birth (0 of 20 in herd A and 13 of 79 in herd B) or seroconverted (6 in herd A and 4 in herd B). Fecal shedding was more common in calves that seroconverted, but overall, there was not a strong association between seropositivity and fecal shedding of Salmonella organisms. CONCLUSIONS AND CLINICAL RELEVANCE: Although the herds differed in serologic response and Salmonella subtype, the duration of fecal shedding among calves was similar between herds.

Yersinia pseudotuberculosis in a closed colony of Egyptian fruit bats (Rousettus aegyptiacus).

An outbreak of Yersinia pseudotuberculosis (Yptb) occurred in a closed colony of Egyptian fruit bats (Rousettus aegyptiacus) and resulted in the death of seven bats over a 6-week period. An initial survey of the remaining bats revealed visceral abscessation characteristic of pseudotuberculosis in five of the 12 bats examined (41.7%), inciting depopulation of the colony. At necropsy, 70% of the 115 bats in the colony exhibited gross evidence suggestive of Yptb infection, including mesenteric lymphadenopathy (ML), hepatic abscessation (HA), and/or splenomegaly (SPM). Thirty of these bats (13 females and 17 males of various ages) were chosen at random and their tissues submitted for bacterial culture and histopathologic examination. Twenty-three of these 30 bats had one or more gross lesions considered consistent with Yptb, including ML, HA, and SPM. On histopathology, four of the 30 bats had necrotizing lesions containing Gram-negative bacteria in multiple organs, while 18 others exhibited mild mesenteric lymphadenitis and hepatitis. Four of the 30 bats had positive cultures for Yptb. Bats with gross evidence of mesenteric lymphadenopathy, splenomegaly, or histopathologic presence of demodicosis or bacteria in tissues were more likely (P < 0.05) to have a positive Yersinia culture. Examination of the correlation between population density and mortality rates of the colony revealed that the mortality rate of subadult bats increased dramatically at the time of the outbreak, when the population density was at its highest. It is suspected that stress, primarily from severe overcrowding, predisposed the bat colony to morbidity and mortality from this organism, which likely originated from a rodent reservoir.