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671.
Two international multicentre randomised controlled trials of drotrecogin alfa (activated) (DrotAA), the Recombinant Human Activated Protein C Worldwide Evaluation of Severe Sepsis (PROWESS) and Administration of Drotrecogin Alfa (Activated) in Early Stage Severe Sepsis (ADDRESS) trials, have produced inconsistent results. When 28-day mortality data from these trials for patients with severe sepsis and at high risk of death are pooled using a standard random-effects meta-analysis technique, there is no statistically significant survival benefit (for patients with Acute Physiology and Chronic Health Evaluation (APACHE II) scores of 25 or more), or a borderline significant benefit (for patients with multi-organ failure). We argue that two important methodological issues might explain the disparate results between the two trials. These issues centre on early trial stopping, which exaggerates treatment effects, and reliance on subgroup analyses, which for DrotAA yields inconsistent results across different definitions of high risk. These concerns call into question the effectiveness of DrotAA in any patients with severe sepsis. Consequently, further randomised trials of this agent in prospectively defined high-risk patients are required to clarify its role in the management of severe sepsis.  相似文献   
672.
Chromosomal microarray analysis (CMA) has improved the diagnostic rate of genomic disorders in pediatric populations, but can produce uncertain and unexpected findings. This article explores clinicians' perspectives and identifies challenges in effectively interpreting results and communicating with families about CMA. Responses to an online survey were obtained from 40 clinicians who had ordered CMA. Content included practice characteristics and perceptions, and queries about a hypothetical case involving uncertain and incidental findings. Data were analyzed using nonparametric statistical tests. Clinicians' comfort levels differed significantly for explaining uncertain, abnormal, and normal CMA results, with lowest levels for uncertain results. Despite clinical guidelines recommending informed consent, many clinicians did not consider it pertinent to discuss the potential for CMA to reveal information concerning biological parentage or predisposition to late‐onset disease, in a hypothetical case. Many non‐genetics professionals ordering CMA did not feel equipped to interpret the results for patients, and articulated needs for education and access to genetics professionals. This exploratory study highlights key challenges in the practice of genomic medicine, and identifies needs for education, disseminated practice guidelines, and access to genetics professionals, especially when dealing with uncertain or unexpected findings.  相似文献   
673.
Confocal scanning laser microscopy (CSLM) represents a novel imaging technique for in vivo microscopic analysis of skin lesions at a level of resolution that allows morphologic analysis of microanatomic structures. We investigated the feasibility of recognizing the cellular constituents of pigmented skin lesions, such as pigmented keratinocytes, melanocytes, and melanophages, by CSLM. Fifteen pigmented lesions (five pigmented seborrheic keratoses, and 10 compound melanocytic nevi) from 15 patients were studied, as well as normal skin. After the clinical lesions were imaged by CSLM, they were biopsied or excised for examination by conventional histology for comparison of the morphologic features. In images obtained by CSLM, pigmented keratinocytes were seen as polygonal cohesive cells with variably bright granular cytoplasm. Melanocytes appeared as bright round, oval, fusiform, or dendritic cells. The architectural growth pattern of melanocytes could be analyzed. Melanocytes were identified by their nested growth pattern as aggregates of bright round to oval structures at the dermoepidermal junction or in the superficial dermis. Melanocytes were also recognizable as single cells along the dermoepidermal junction, usually separated from each other by a variable number of keratinocytes. Melanophages appeared as large bright plump cells with ill-defined cytoplasmic borders, usually located around or near vessels of the superficial dermis. Our results demonstrate that the cellular constituents of pigmented lesions can be recognized by CSLM. This technique sets a new paradigm for noninvasive quasihistologic examination of pigmented lesions in vivo and merits further evaluation for diagnostic use.  相似文献   
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676.
Cytotoxic T‐lymphocyte‐associated protein‐4, programmed cell death protein and programmed cell death protein ligand 1 monoclonal antibodies (immune checkpoint inhibitors), are used to treat various malignancies. Their mechanism of action involves the inhibition of negative regulators of immune activation, resulting in immune‐related adverse events (irAEs) including endocrinopathies, pneumonitis, colitis, hepatitis and dermatological events. Dermatological irAEs include maculopapular rash, pruritus, vitiligo, blistering disorders, mucocutaneous lichenoid eruptions, rosacea and the exacerbation of psoriasis. Alopecia secondary to immune checkpoint inhibitors has been reported in 1·0–2·0% of treated patients. Our objective is to characterize for the first time the clinicopathology of patients with alopecia areata (AA) secondary to immune checkpoint inhibitors, including the first report of anti‐PD‐L1 therapy‐induced AA, and review of the literature. Four cases of patients who developed partial or complete alopecia during treatment with immune checkpoint inhibitors for underlying cancer were identified from our clinics. Methods include the review of the history and clinicopathologic features. Three patients (75%) had AA and one had universalis. Two patients had a resolution after topical, oral or intralesional therapies and one had a resolution after immunotherapy was discontinued; all regrown hair exhibited poliosis. One of the four patients had coincident onychodystrophy. This report describes a series of four patients who developed partial or complete alopecia (i.e. areata and universalis) during treatment with immune checkpoint inhibitor therapies for cancer. The recognition and management of hair‐related irAEs are important for pretherapy counselling and interventions that contribute to maintaining optimal health‐related quality of life in patients.  相似文献   
677.
A conjunctival melanocytic nevus may on occasion be difficult to distinguish from melanoma both clinically and histopathologically. An unambiguous correct diagnosis is critical because of major differences in management and prognosis. We evaluated a fluorescence in situ hybridization (FISH) assay, which has previously been shown to be of value for the diagnosis of melanocytic nevi and melanomas of the skin, using probes targeting 6p25 (RREB1), 6q23 (MYB), 11q13 (CCND1) and centromere 6 (CEP6), for its potential to assist in the distinction of conjunctival melanocytic nevi from melanomas. Four melanocytic nevi and eight melanomas of the conjunctiva were analyzed. Two of the melanomas were diagnostically problematic because of suboptimal histopathology. None of the conjunctival melanocytic nevi showed a level of chromosomal aberrations that met FISH criteria for a diagnosis of melanoma. All eight conjunctival melanomas (six unequivocal and two suspicious lesions) met FISH criteria for melanoma. Thus, results from FISH assay targeting 6p25, 6q23, 11q13 and centromere 6 correlated well with the histopathologic diagnoses and supported the histopathologic suspicion in two problem cases. The findings encourage further exploration of this technique as an ancillary method for the work‐up of conjunctival melanocytic proliferations. Busam KJ, Fang Y, Jhanwar SC, Pulitzer MP, Marr B, Abramson DH. Distinction of conjunctival melanocytic nevi from melanomas by fluorescence in situ hybridization.  相似文献   
678.
Well‐differentiated neuroendocrine tumors metastasize to the skin uncommonly, and only 35 cases are reported in the literature. In only five of these patients, cutaneous metastases were the presenting symptom of malignancy; herein, we report four such cases. Two patients were female and two male, aged 50–74 years (mean: 64.5 years), each with a solitary painless, slowly enlarging, non‐ulcerated cutaneous nodule of 3–12 months duration (mean: 9 months). The lesions were on the scalp (n = 3) and trunk (n = 1), and ranged in greatest dimension from 0.5 to 2.5 cm. The distinction from other microscopically similar entities, and the interpretation of origination from gastrointestinal, pancreatic or respiratory system primaries, was made clinically, or was based on the morphological features and the immunohistochemical profile. One patient died of the disease progression after 36 months whereas two patients are alive with significant disease progression after 24 and 60 months. Metastatic neuroendocrine tumor should be considered in the differential diagnosis of cutaneous tumors with neuroendocrine morphology even in patients with no known history of visceral malignancy.  相似文献   
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