RESUMO
Magnetotail reconnection plays a crucial role in explosive energy conversion in geospace. Because of the lack of in-situ spacecraft observations, the onset mechanism of magnetotail reconnection, however, has been controversial for decades. The key question is whether magnetotail reconnection is externally driven to occur first on electron scales or spontaneously arising from an unstable configuration on ion scales. Here, we show, using spacecraft observations and particle-in-cell (PIC) simulations, that magnetotail reconnection starts from electron reconnection in the presence of a strong external driver. Our PIC simulations show that this electron reconnection then develops into ion reconnection. These results provide direct evidence for magnetotail reconnection onset caused by electron kinetics with a strong external driver.
RESUMO
UNLABELLED: Promoter capture Hi-C (PCHi-C) allows the genome-wide interrogation of physical interactions between distal DNA regulatory elements and gene promoters in multiple tissue contexts. Visual integration of the resultant chromosome interaction maps with other sources of genomic annotations can provide insight into underlying regulatory mechanisms. We have developed Capture HiC Plotter (CHiCP), a web-based tool that allows interactive exploration of PCHi-C interaction maps and integration with both public and user-defined genomic datasets. AVAILABILITY AND IMPLEMENTATION: CHiCP is freely accessible from www.chicp.org and supports most major HTML5 compliant web browsers. Full source code and installation instructions are available from http://github.com/D-I-L/django-chicp CONTACT: ob219@cam.ac.uk.
Assuntos
Internet , Regiões Promotoras Genéticas , Elementos Reguladores de Transcrição , Software , Cromossomos , Gráficos por Computador , Genoma , GenômicaRESUMO
We identified and treated a solid, growing fungal tumor mass in a patient with disseminated histoplasmosis. Although the most commonly reported intraocular lesions from disseminated histoplasmosis are areas of inactive chorioretinal scars or areas of localized subretinal neovascular membrane formation, a focus of active fungal growth needs to be ruled out in all such cases. When a solid tumor mass is identified, the most effective way of preserving vision is with systemic antifungal therapy.
Assuntos
Neoplasias Oculares/etiologia , Histoplasmose/complicações , Anfotericina B/uso terapêutico , Neoplasias Oculares/tratamento farmacológico , Humanos , Cetoconazol/uso terapêutico , Masculino , Pessoa de Meia-Idade , Acuidade Visual/efeitos dos fármacosRESUMO
Naproxen effects on the ocular inflammatory response following extracapsular lens extraction were studied in rabbits. Twelve hours before surgery, rabbits were given 20 mg of a 5 mg/ml naproxen suspension by gavage. A maintenance dose of 10 mg naproxen 3 times per day was started on the day of lensectomy and continued throughout the entire observation period. Phakic and aphakic control rabbits received no drug suspension. Central corneal thickness and intraocular pressure measurements were determined pre-operatively, at 4 and 24 h post-operatively and every 24 h thereafter. Four groups of rabbits, sacrificed at 24, 48, 72, and 168 h after lensectomy, had anterior chamber paracentesis performed for PMN (polymorphonuclear leucocyte) counts and determination of protein content. A 5th group had both paracentesis and iris-ciliary body excision for PGE2 assay at 24 h. No parameter was significantly altered by the naproxen regimen compared to untreated rabbits.
Assuntos
Extração de Catarata/efeitos adversos , Naproxeno/farmacologia , Complicações Pós-Operatórias/prevenção & controle , Uveíte Anterior/prevenção & controle , Animais , Humor Aquoso/análise , Córnea/efeitos dos fármacos , Dinoprostona , Proteínas do Olho/análise , Feminino , Pressão Intraocular/efeitos dos fármacos , Contagem de Leucócitos , Masculino , Naproxeno/administração & dosagem , Neutrófilos/efeitos dos fármacos , Prostaglandinas E/análise , CoelhosRESUMO
We present a patient with coccidioidal meningitis whose diagnosis was not confirmed until a skin biopsy was performed. Because he lived in an area where coccidioidomycosis is not endemic, his meningitis was at first attributed to tuberculosis or sarcoidosis. After a verrucous lesion from the face was biopsied and the diagnosis substantiated, the patient responded well to consolidation therapy consisting of intrathecal amphotericin B and oral ketoconazole.
Assuntos
Coccidioidomicose/diagnóstico , Dermatomicoses/diagnóstico , Meningite/diagnóstico , Adulto , Anfotericina B/uso terapêutico , Coccidioidomicose/tratamento farmacológico , Coccidioidomicose/patologia , Dermatomicoses/tratamento farmacológico , Dermatomicoses/patologia , Humanos , Masculino , Meningite/tratamento farmacológicoRESUMO
Mucous gland adenoma of the bronchus is a truly benign bronchoid neoplasm which responds to simple surgical excision, sparing as much functional lung tissue as possible. The patient here reported is well one year after such treatment.
Assuntos
Adenoma/patologia , Neoplasias Brônquicas/patologia , Adenoma/cirurgia , Adulto , Neoplasias Brônquicas/cirurgia , Feminino , HumanosRESUMO
Only 12% of 50 patients lived 5 years or longer. Those who survived the longest were those with the tumor in the distal part of the lower extremity, with a well differentiated or chondroblastic tumor, or those who underwent radical surgery. Patients treated with surgery and chemotherapy lived about 1.5 months longer than those treated with sugery alone and about 1.2 months longer than those who had radiation included in the therapy. For a patient with a diagnosis of osteosarcoma, the prognosis was to be grave, no matter which methods of treatment were used.
Assuntos
Neoplasias Ósseas , Osteossarcoma , Adolescente , Adulto , Alabama , População Negra , Criança , Feminino , Neoplasias Femorais , Fíbula , Humanos , Úmero , Masculino , Pessoa de Meia-Idade , Metástase Neoplásica , Osteossarcoma/mortalidade , Osteossarcoma/terapia , Gravidez , Complicações na Gravidez , Fatores Sexuais , TíbiaRESUMO
A patient with Whipple's disease is described whose small bowel biopsy demonstrated antigenicity to rabbit antisera to groups A, B, C, and G streptococci and Shigella flexneri, but not to antisera to pneumococcus or Shigella sonnei by immunofluorescent techniques. In addition, the patient's lymphocytes responded normally to phytohemagglutinin and to concanavalin A. These studies support the idea what Whipple's disease is mediated by a bacteria-like agent which shares certain antigenic similarities with groups A, B, C, and G streptococci and S. flexneri, and that T cell dysfunction does not appear to be an essential prerequisite for the disease.
Assuntos
Doença de Whipple/imunologia , Anticorpos Antibacterianos , Humanos , Imunoglobulinas/análise , Intestino Delgado/imunologia , Ativação Linfocitária , Masculino , Pessoa de Meia-Idade , Shigella/imunologia , Streptococcus/imunologiaRESUMO
A case of dysplastic gangliocytoma of the cerebellum, a rare disorder with unknown etiology and pathogenesis, was studied ultrastructurally. The intranuclear inclusions identified were not seen to be of viral origin. The ultrastructural characteristics of the abnormal cells support the prevailing theory that these cells represent hypertrophied granular neurons.
Assuntos
Neoplasias Cerebelares/ultraestrutura , Ganglioneuroma/ultraestrutura , Adulto , Núcleo Celular/ultraestrutura , Neoplasias Cerebelares/congênito , Ganglioneuroma/congênito , Humanos , Corpos de Inclusão/ultraestrutura , Masculino , Microscopia EletrônicaRESUMO
A histologic grading system based on tumor differentiation was applied in a retrospective study of 26 patients with Wilms' tumor to determine if it might provide an index to prognosis. The results were compared to those obtained by applying a histologic classification based on the presence or absence of individual histologic structures to the same tumors. Low grade tumors with predominance of differentiated structures--glomeruli and tubules--were associated with a better cure rate than high grade tumors composed mainly of undifferentiated spindle elements. The presence of undifferentiated large cells correlated with poor cure rate. The findings suggest that histologic grading may be valid as a prognostic factor in Wilms' tumor.
Assuntos
Neoplasias Renais/patologia , Tumor de Wilms/patologia , Adolescente , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Neoplasias Renais/terapia , Masculino , Prognóstico , Estudos Retrospectivos , Tumor de Wilms/terapiaRESUMO
This presentation describes criteria that we found most helpful in classifying the various proliferative changes of the breast and in separating papillary carcinoma from other benign papillary lesions. The criteria we used are easily understood and extremely reproducible. The true incidence of benign proliferative changes in fibrocystic disease and the significance of these lesions in later development of cancer were determined by studying 200 randomly selected cases of fibrocystic disease seen at least 10 years earlier. Of the 200 cases of fibrocystic disease, 40 showed intraductal papillomatosis or terminal duct hyperplasia. None of the patients with benign proliferative lesions for whom we have complete follow-up data (up to 14 years) developed cancer. In order to determine the type of proliferating cells in papillary carcinoma and benign proliferative lesions, some of the recently encountered cases were studied by transmission and scanning electron microscopy and histochemistry. Our ultrastructural and histochemical study suggests that both epithelial and myoepithelial cells participate in papillary lesions of the breast.
Assuntos
Neoplasias da Mama/patologia , Carcinoma Papilar/patologia , Papiloma/patologia , Adulto , Mama/patologia , Feminino , Humanos , Hiperplasia , Pessoa de Meia-Idade , Lesões Pré-Cancerosas/patologiaRESUMO
This report concerns an electron microscopic study of a sacrococcygeal chordoma and its in vitro cultured cells. In vitro, the cells that proliferated in the early phase were predominantly non-vacuolated stellate cells, which were later transformed into vacuolated cells. This suggests that various cell types seen in vivo represent variants of the same cell type at different stages of differentiation and cellular activity. The in vitro tumor cells also show the origin of their vacuoles from both rough endoplasmic reticulum and Golgi membranes. The finding of amorphous and granular material and collagen fibrils in the extracellular spaces of cultured cells seems to suggest that chordoma cells have certain synthetic and secretory activity.
Assuntos
Cordoma/patologia , Região Sacrococcígea , Diferenciação Celular , Cordoma/metabolismo , Tecido Conjuntivo/ultraestrutura , Técnicas de Cultura , Retículo Endoplasmático/ultraestrutura , Complexo de Golgi/ultraestrutura , Humanos , Masculino , Microscopia de Contraste de Fase , Pessoa de Meia-Idade , Vacúolos/ultraestruturaRESUMO
The electron microscopic features of a leiomyosarcoma occurring in the lung, a rare site, were studied; Unusual was the fwnding of extremely electron-dense bands that interrupted the longitudinally-arranged microfilaments and dense bodies of many of the tumor cells. These bands superficially resembled anomalous Z-bands seen in nemalin myopathy and aging rat cardiac muscle, but have not been described to occur in smooth muscle tumors. They are thought to represent condensations of dense bodies in degenerating tumor cells.
Assuntos
Leiomiossarcoma/patologia , Neoplasias Pulmonares/patologia , Idoso , Humanos , Leiomiossarcoma/cirurgia , Pulmão/patologia , Neoplasias Pulmonares/cirurgia , Masculino , Microscopia Eletrônica , Mitocôndrias/ultraestrutura , Músculo Liso/patologia , Miofibrilas/ultraestrutura , Organoides/ultraestrutura , Coloração e RotulagemRESUMO
The electron microscopic features of a leiomyosarcoma occurring in the lung, a rare site, were studied. Unusual was the finding of extremely electron-dense bands that interrupted the longitudinally-arranged microfilaments and dense bodies of many of the tumor cells. The bands superficially resembled anomalous Z-bands seen in nemalin myopathy and aging rat cardiac muscle, but have not been described to occur in smooth muscle tumors. They are thought to represent condensations of dense bodies in degenerating tumor cells.