RESUMO
We describe a novel type of human thrombocytopenia characterized by the appearance of giant platelets and variable neutropenia. Searching for the molecular defect, we found that neutrophils had strongly reduced sialyl-Lewis X and increased Lewis X surface expression, pointing to a deficiency in sialylation. We show that the glycosylation defect is restricted to α2,3-sialylation and can be detected in platelets, neutrophils, and monocytes. Platelets exhibited a distorted structure of the open canalicular system, indicating defective platelet generation. Importantly, patient platelets, but not normal platelets, bound to the asialoglycoprotein receptor (ASGP-R), a liver cell-surface protein that removes desialylated thrombocytes from the circulation in mice. Taken together, this is the first type of human thrombocytopenia in which a specific defect of α2,3-sialylation and an induction of platelet binding to the liver ASGP-R could be detected.
Assuntos
Ácido N-Acetilneuramínico/metabolismo , Oligossacarídeos/metabolismo , Trombocitopenia/metabolismo , Trombocitopenia/patologia , Animais , Receptor de Asialoglicoproteína/metabolismo , Plaquetas/metabolismo , Plaquetas/patologia , Plaquetas/ultraestrutura , Criança , Feminino , Granulócitos/metabolismo , Humanos , Interleucina-8/metabolismo , Fígado/metabolismo , Camundongos , Mutação/genética , Neutropenia/complicações , Neutropenia/patologia , Proteínas de Transporte de Nucleotídeos/genética , Fenótipo , Ligação Proteica , Selectinas/metabolismo , Antígeno Sialil Lewis X , Trombocitopenia/complicaçõesRESUMO
Airbags can be lifesaving during a motor vehicle accident (MVA), but airbag deployment has been the cause of dermatologic injuries including irritant dermatitis, as well as thermal, friction, and chemical burns. A highly corrosive alkaline aerosol composed of sodium hydroxide, sodium bicarbonate, and metallic oxides is released during airbag deployment. We present the case of a 35-year-old man who developed a bullous reaction to released by-products from airbag deployment during an MVA.
Assuntos
Air Bags , Queimaduras Químicas , Acidentes de Trânsito , Adulto , Air Bags/efeitos adversos , Queimaduras Químicas/etiologia , Fricção , Humanos , Masculino , Veículos AutomotoresRESUMO
BACKGROUND: Hepatoma-derived growth factor (HDGF) belongs to a polypeptide family containing five additional members called HDGF related proteins 1-4 (HRP-1 to -4) and Lens epithelial derived growth factor. Whereas some family members such as HDGF and HRP-2 are expressed in a wide range of tissues, the expression of others is very restricted. HRP-1 and -4 are only expressed in testis, HRP-3 only in the nervous system. Here we investigated the expression of HDGF, HRP-2 and HRP-3 in the central nervous system of adult rats on the cellular level by immunohistochemistry. In addition we performed Western blot analysis of various brain regions as well as neuronal and glial cell cultures. RESULTS: HDGF was rather evenly expressed throughout all brain regions tested with the lowest expression in the substantia nigra. HRP-2 was strongly expressed in the thalamus, prefrontal and parietal cortex, neurohypophysis, and the cerebellum, HRP-3 in the bulbus olfactorius, piriform cortex and amygdala complex. HDGF and HRP-2 were found to be expressed by neurons, astrocytes and oligodendrocytes. In contrast, strong expression of HRP-3 in the adult nervous system is restricted to neurons, except for very weak expression in oligodendrocytes in the brain stem. Although the majority of neurons are HRP-3 positive, some like cerebellar granule cells are negative. CONCLUSION: The coexpression of HDGF and HRP-2 in glia and neurons as well as the coexpression of all three proteins in many neurons suggests different functions of members of the HDGF protein family in cells of the central nervous system that might include proliferation as well as cell survival. In addition the restricted expression of HRP-3 point to a special function of this family member for neuronal cells.
Assuntos
Química Encefálica , Peptídeos e Proteínas de Sinalização Intercelular/análise , Fatores Etários , Animais , Astrócitos/química , Western Blotting , Encéfalo/embriologia , Encéfalo/crescimento & desenvolvimento , Encéfalo/metabolismo , Células Cultivadas/química , Peptídeos e Proteínas de Sinalização Intercelular/biossíntese , Microglia/química , Proteínas do Tecido Nervoso , Neurônios/química , Oligodendroglia/química , Especificidade de Órgãos , Ratos , Ratos WistarRESUMO
OBJECTIVE: Reflexive testing of bronchoalveolar lavage (BAL) specimens with Gomori methenamine silver (GMS) and acid-fast bacillus (AFB) stains is not routinely performed by most institutions. Instead, these stains are usually ordered to evaluate for the presence of fungal elements and/or acid-fast organisms if initial histopathologic assessment suggests the presence of these pathogens. Our institution, however, performs these stains on all BAL specimens. Thus, we sought to determine whether this practice was cost effective, considering the turnaround time and diagnostic efficacy of these tests. METHODS: We retrospectively reviewed 488 BAL specimens performed at two military healthcare institutions over a 2-year period and performed a cost analysis with review of the impact on turnaround time. RESULTS: Of the 488 cases, we identified only 3 (~0.6%) with infections by acid-fast or fungal organisms, at an estimated total cost of $12,151.20 and an average delay of 3.0 to 3.5 hours for slide preparation. CONCLUSION: Our results suggest that in a largely young and healthy population such as ours, it may be more feasible to perform these stains on BAL specimens on a case-by-case basis rather than automatically on every specimen, to control costs and enhance productivity.
Assuntos
Bacillus/metabolismo , Lavagem Broncoalveolar/métodos , Metenamina/metabolismo , Pneumonia por Pneumocystis/diagnóstico , Pneumonia por Pneumocystis/microbiologia , Coloração e Rotulagem/métodos , Lavagem Broncoalveolar/economia , Reações Falso-Negativas , Feminino , Humanos , Estudos Longitudinais , Masculino , Estudos Retrospectivos , Coloração e Rotulagem/economiaRESUMO
Primary renal lymphoma (PRL) is a rare entity with a history of controversy regarding its existence. Lymphomatous involvement of the kidney is more commonly seen secondarily to spread from an adjacent lymphomatous mass, rather than arising primarily from the kidney. PRL can mimic other renal lesions such as renal cell carcinoma, renal abscess, and metastasis; therefore, an early diagnosis is crucial to guide treatment and properly assess prognosis. We present a rare case of a 77 year-old male who presented with hematuria and PRL mimicking a subcapsular hematoma.
Assuntos
Hematoma/diagnóstico , Neoplasias Renais/diagnóstico , Linfoma de Zona Marginal Tipo Células B/diagnóstico , Idoso , Diagnóstico Diferencial , Hematúria/etiologia , Humanos , Biópsia Guiada por Imagem/métodos , Imageamento por Ressonância Magnética , Masculino , Tomografia por Emissão de Pósitrons , Radiografia Intervencionista , Tomografia Computadorizada por Raios XRESUMO
BACKGROUND: Carotid body tumors are uncommon neoplasms with unique epidemiology and management demands. Cervical embryology is complex. Developmental abnormalities can result in ectopic displacement of native tissues. METHODS: We present the case of a 21-year-old female with bilateral carotid body paragangliomas who presented to our clinic seeking excision of the symptomatic right-sided tumor. RESULTS: The patient was successfully treated with surgical excision. Two rare anatomic variants were identified in her surgical specimen: a carotid sheath parathyroid gland and ectopic thymus tissue. CONCLUSIONS: This patient represents an unreported combination of pathologic and anatomic phenomena. The paraganglioma resulted from a familial genetic mutation that is well studied in this patient's ethnic population (Dutch), and the literature on this topic is reviewed herein. The 2 anatomic variants likely represent a single, embryologic glitch that will carry no physiologic sequelae. The clinical application of this ectopic anatomy and the common embryologic origins are discussed.
Assuntos
Tumor do Corpo Carotídeo/patologia , Paraganglioma/patologia , Glândulas Paratireoides/patologia , Timo/patologia , Adulto , Tumor do Corpo Carotídeo/cirurgia , Feminino , Humanos , Paraganglioma/cirurgia , Glândulas Paratireoides/cirurgia , Timo/cirurgiaRESUMO
OBJECTIVE: To investigate the effect of cigarette smoke exposure on ciliation and ciliogenesis in human oviductal epithelium. DESIGN: Molecular analysis using human tubal segments. SETTING: Academic medical center. PATIENT(S): Twenty women undergoing elective tubal sterilization procedure. INTERVENTION(S): Expression of ciliated cell-specific markers was compared in tubal segments from smokers and nonsmokers using quantitative immunohistochemistry and Western blot analysis. The expression of transcription factors in the motile ciliogenesis program was compared using quantitative polymerase chain reaction and quantitative immunohistochemistry. MAIN OUTCOME MEASURE(S): Oviductal ciliation and expression of transcription factors involved in ciliogenesis. RESULT(S): No significant differences were detected in density of ciliation between groups. Neither number of years of smoking nor pack-year history correlated with density of ciliation. Expression of ciliogenic transcription factors FOXJ1, RFX2, and RFX3 was consistent between groups. CONCLUSION(S): Few studies have evaluated the relationship between smoking and ciliated epithelium in human oviducts. Cigarette smoking does not seem to result in quantitative differences in the density of ciliation nor expression of ciliogenesis factors. Our findings suggest that pathophysiologic mechanisms other than ciliation account for the increased risk of ectopic pregnancy in women who smoke.
Assuntos
Cílios/patologia , Cílios/fisiologia , Tubas Uterinas/fisiologia , Fumar/efeitos adversos , Adulto , Biópsia , Proteínas de Ligação a DNA/fisiologia , Epitélio/patologia , Epitélio/fisiologia , Tubas Uterinas/patologia , Feminino , Fatores de Transcrição Forkhead/fisiologia , Humanos , Incidência , Gravidez , Gravidez Ectópica/epidemiologia , Estudos Prospectivos , Fatores de Transcrição de Fator Regulador X , Fatores de Transcrição/fisiologiaRESUMO
Less than 10% of chondrosarcomas occur in children. In addition, as little as 0.5% of low-grade chondrosarcomas arise secondarily from benign chondroid lesions. The presence of focal pain is often used to crudely distinguish a chondrosarcoma (which is usually managed with wide surgical excision), from a benign chondroid lesion (which can be followed by clinical exams and imaging surveillance). Given the difficulty of localizing pain in the pediatric population, initial radiology findings and short-interval follow-up, both imaging and clinical, are critical to accurately differentiate a chondrosarcoma from a benign chondroid lesion. To our knowledge, no case in the literature discusses a chondrosarcoma possibly arising secondarily from an enchondroma in a pediatric patient. We present a clinicopathologic and radiology review of conventional chondrosarcomas. We also attempt to further the understanding of how to manage a chondroid lesion in the pediatric patient with only vague or bilateral complaints of pain.