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1.
Toxicon ; 154: 42-49, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30273705

RESUMO

INTRODUCTION: Gelsemium poisoning is caused by consumption of the deadly Gelsemium species such as Gelsemium elegans, leading to significant gastrointestinal, neurological and cardio-respiratory toxicities. In 2011 (Cluster 1) and 2012 (Cluster 2), the authors encountered two clusters of gelsemium poisoning after consumption of the non-toxic parasitic plant Cassytha filiformis. The current study aims to examine the mechanism of gelsemium poisoning mediated by a benign parasitic plant. METHODS: Qualitative analysis of toxic gelsemium alkaloids using liquid chromatography-tandem mass spectrometry (LC-MS/MS) was performed on the herbal and urine samples from both clusters to confirm exposure. Morphological examination, qualitative analysis of aporphine alkaloids using liquid chromatography-ion trap-time of flight mass spectrometry (LC-IT-TOF/MS) and Sanger sequencing were performed on the plant sample from Cluster 2 to confirm its identity. A field study was conducted in local countryside and C. filiformis was collected for histological, LC-MS/MS and LC-IT-TOF/MS analyses to study its interaction with G. elegans. RESULTS: Gelsemium alkaloids that are not naturally present in C. filiformis were detected in the patients' herbal and urine samples. Misidentification and contamination with G. elegans during the preparation process were excluded by morphological examination of the plant sample from Cluster 2. Its identity as C. filiformis was verified with LC-IT-TOF/MS and molecular analyses. Histological, LC-MS/MS and LC-IT-TOF/MS analyses of C. filiformis collected during the field study confirmed that its haustoria penetrated the vascular bundles of G. elegans and absorbed its gelsemium toxins. CONCLUSIONS: The non-toxic plant C. filiformis absorbed toxic gelsemium alkaloids from its host, G. elegans, and led to gelsemium poisoning in our patients. Our study provides new insights into the toxicology of such plants. Benign parasitic plants may lead to potentially life-threatening poisoning if it parasitizes toxic hosts and absorbs their phytotoxins. The public awareness of risks associated with the use of these medicinal parasitic plants should be raised.


Assuntos
Alcaloides/química , Alcaloides/intoxicação , Gelsemium/química , Gelsemium/intoxicação , Lauraceae/intoxicação , Adulto , Alcaloides/metabolismo , Cromatografia Líquida de Alta Pressão , Gelsemium/metabolismo , Gelsemium/parasitologia , Humanos , Lauraceae/metabolismo , Pessoa de Meia-Idade , Espectrometria de Massas em Tandem , Adulto Jovem
2.
Int J Biomed Sci ; 3(1): 72-5, 2007 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23675025

RESUMO

Pancreatic mucinous cystic neoplasms (PMCN) predominantly affect women in the reproductive age, are located in the body and tail of the pancreas, and share morphological features with similar tumors of the ovary. We report the detection of human papillomavirus (HPV) using several different PCR protocols in a borderline PMCN from a female patient. Type-specific PCR demonstrated the HPV to be type 16. If confirmed by others, this group of neoplasms might become preventable by HPV vaccination.

3.
Clin Chim Acta ; 376(1-2): 229-32, 2007 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-16949066

RESUMO

BACKGROUND: Cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL) is an adult-onset hereditary condition caused by mutations in the Notch3 gene. A Chinese man was studied. METHOD: Electronic microscopy examination of skin biopsy. The Notch3 gene was screened for mutations by polymerase chain reaction and direct DNA sequencing. RESULTS: Electronic microscopy showed the presence of deposits of granular osmiophilic material in dermal capillaries in the index patient. A novel heterozygous C271F in exon 6 was detected in the index patient. This heterozygous C271F mutation was also detected in the asymptomatic elder son but was not detected in the asymptomatic wife of the patient. Allele specific amplification showed that C271F was not detected in 100 normal subjects. CONCLUSION: We established the molecular basis of CADASIL in a Chinese man. Mutation detection assay provides a reliable method for confirming the diagnosis of CADASIL.


Assuntos
CADASIL/genética , Genes Dominantes , Receptores Notch/genética , Povo Asiático , CADASIL/diagnóstico , Capilares/patologia , Análise Mutacional de DNA , Humanos , Masculino , Pessoa de Meia-Idade , Mutação , Linhagem , Receptor Notch3
4.
Pediatr Nephrol ; 22(1): 136-40, 2007 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-16967281

RESUMO

We report a sporadic large-scale mitochondrial deletion in a paediatric patient with Fanconi's syndrome. Renal biopsy disclosed chronic interstitial nephritis. Ultrastructural examination of the renal tissue showed many giant atypical mitochondria. Histochemical stains revealed markedly reduced cytochrome c oxidase (COX). Genetic analysis disclosed a novel mitochondrial deletion of 7.3 kb in both peripheral blood and renal tissue. Mitochondrial diseases have heterogeneous clinical phenotypes; mutation analysis has proved to be an effective tool in confirming the diagnosis.


Assuntos
DNA Mitocondrial/genética , Síndrome de Fanconi/genética , Deleção de Genes , Biópsia , Criança , Complexo IV da Cadeia de Transporte de Elétrons/genética , Complexo IV da Cadeia de Transporte de Elétrons/metabolismo , Síndrome de Fanconi/diagnóstico , Feminino , Humanos , Túbulos Renais/metabolismo , Túbulos Renais/patologia , Mitocôndrias/ultraestrutura , Mutação/genética
5.
Int J Biomed Sci ; 2(4): 422-7, 2006 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23675011

RESUMO

Despite the availability of the PAP test, cervical cancer continues to cause considerable morbidity and mortality. Many women default cervical cytology for a variety of reasons. This demands the development of alternative screening strategies, such as HPV testing on self-procured cervical-vaginal specimens in order to capture this group of women. We investigated the self-procured air-dried vaginal discharge for HPV testing. We recruited 82 patients with HPV-associated cervical lesions and 36 patients with normal cervical pathology. Participants were briefed and informed consents obtained. Each was then given a kit containing written instructions, a slim napkin, an empty zip-lock plastic bag for soiled napkin specimen, and a return envelope. After wearing the napkin for the day, the patient removes it, dries it, and returns the specimen by mail. Specimens were batched and a 0.5 cm area of each stained napkin was tested for HPV by PCR. Specimens from all 26 patients with high-grade (CIN 2 or above) HPV-induced cervical lesions and 4 of 36 normal subjects tested positive for HPV, giving a sensitivity and specificity of 100% and 88.9%, respectively. We propose offering to women who refuse cervical cytology the alternative screening strategy of testing of self-procured air-dried vaginal discharge for HPV. This method of cervical cancer screening is also suitable for people living in remote regions of the world.

6.
Hepatology ; 39(2): 302-10, 2004 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-14767982

RESUMO

Liver impairment is commonly reported in up to 60% of patients who suffer from severe acute respiratory syndrome (SARS). Here we report the clinical course and liver pathology in three SARS patients with liver impairment. Three patients who fulfilled the World Health Organization case definition of probable SARS and developed marked elevation of alanine aminotransferase were included. Percutaneous liver biopsies were performed. Liver specimens were examined by light and electron microscopy, and immunohistochemistry. Reverse-transcriptase polymerase chain reaction (RT-PCR) using enhanced real-time PCR was applied to look for evidence of SARS-associated coronavirus infection. Marked accumulation of cells in mitosis was observed in two patients and apoptosis was observed in all three patients. Other common pathologic features included ballooning of hepatocytes and mild to moderate lobular lymphocytic infiltration. No eosinophilic infiltration, granuloma, cholestasis, fibrosis, or fibrin deposition was noted. Immunohistochemical studies revealed 0.5% to 11.4% of nuclei were positive for proliferative antigen Ki-67. RT-PCR showed evidence of SARS-associated coronavirus in the liver tissues, but not in the sera of all 3 patients. However, electron microscopy could not identify viral particles. No giant mitochondria, micro- or macro-vesicular steatosis was observed. In conclusion, hepatic impairment in patients with SARS is due to SARS-associated coronavirus infection of the liver. The prominence of mitotic activity of hepatocytes is unique and may be due to a hyperproliferative state with or without disruption of cell cycle by the coronavirus. With better knowledge of pathogenesis, specific therapy may be targeted to reduce viral replication and modify the disease course.


Assuntos
Coronavirus/isolamento & purificação , Hepatite Viral Humana/virologia , Síndrome Respiratória Aguda Grave/complicações , Adulto , Anti-Inflamatórios/uso terapêutico , Apoptose , Biópsia , Coronavirus/genética , DNA Viral/análise , Combinação de Medicamentos , Feminino , Inibidores da Protease de HIV/uso terapêutico , Hepatite Viral Humana/tratamento farmacológico , Hepatite Viral Humana/patologia , Humanos , Fígado/patologia , Fígado/virologia , Lopinavir , Metilprednisolona/uso terapêutico , Pessoa de Meia-Idade , Mitose , Pirimidinonas/uso terapêutico , Ritonavir/uso terapêutico , Síndrome Respiratória Aguda Grave/tratamento farmacológico , Síndrome Respiratória Aguda Grave/patologia
7.
Diagn Cytopathol ; 28(3): 140-1, 2003 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-12619095

RESUMO

Human papillomavirus was successfully detected by polymerase chain reaction (PCR) in menstrual blood or vaginal discharge collected in sanitary napkins in 100% of 17 women having koilocytosis, cervical intraepithelial neoplasia, or squamous carcinoma. We advocate this form of cervical cancer screening because of its high sensitivity and acceptance by patients.


Assuntos
Absorventes Higiênicos/virologia , Programas de Rastreamento/métodos , Menstruação , Papillomaviridae/isolamento & purificação , Displasia do Colo do Útero/diagnóstico , Neoplasias do Colo do Útero/prevenção & controle , DNA Viral/análise , Feminino , Humanos , Papillomaviridae/genética , Reação em Cadeia da Polimerase , Sensibilidade e Especificidade , Displasia do Colo do Útero/virologia
8.
Acta Cytol ; 46(5): 893-8, 2002.
Artigo em Inglês | MEDLINE | ID: mdl-12365226

RESUMO

BACKGROUND: T-cell-rich B-cell lymphoma (TCRBL) is a lymphoma of B-cell type associated with a prominent component of T cells (constituting > 50% of the cellular population). We report the first case of TCRBL diagnosed by fine needle aspiration (FNA). It was confirmed by subsequent lymph node excision biopsy. CASE: A 37-year-old woman presented with a short history of chest wall pain. Examination revealed induration, warmth and armorlike swelling of the right anterior chest wall, axilla and upper arm, with matted lymph nodes in the ipsilateral axilla and supraclavicular fossa. FNA showed a polymorphic, lymphoid aspirate, among which were many small lymphocytes, significant numbers of centroblastlike cells and a few markedly atypical lymphoid cells with convoluted nuclei. Histiocytes, freely lying karyorrhectic debris and mitotic figures were readily identified. Plasma cells, eosinophils and Reed-Sternberg cells were not seen. The cell block contained similar cells, with larger lymphoid cells scattered among smaller lymphocytes. Immunohistochemical studies showed that the larger cells were B cells. Molecular studies on the cell block confirmed an immunoglobulin gene rearrangement. CONCLUSION: TCRBL is a distinct type of lymphoma that can be accurately diagnosed by FNA.


Assuntos
Histiócitos/patologia , Linfoma de Células B/diagnóstico , Linfoma Difuso de Grandes Células B/diagnóstico , Linfoma não Hodgkin/diagnóstico , Linfócitos T/patologia , Adulto , Biópsia por Agulha , Diagnóstico Diferencial , Feminino , Rearranjo Gênico da Cadeia gama dos Receptores de Antígenos dos Linfócitos T , Genes de Imunoglobulinas , Genes Codificadores da Cadeia gama de Receptores de Linfócitos T , Humanos , Imuno-Histoquímica , Imunofenotipagem , Linfonodos/patologia , Linfoma de Células B/patologia , Linfoma Difuso de Grandes Células B/patologia , Linfoma não Hodgkin/patologia , Mitose
9.
Arch Pathol Lab Med ; 126(8): 972-4, 2002 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-12171499

RESUMO

Gastrointestinal stromal tumors (GISTs) are a heterogeneous group of mesenchymal tumors with a wide spectrum of histologic features and consistent expression of c-Kit. We describe an 85-year-old woman who presented with left lower quadrant abdominal pain and was subsequently diagnosed as having a malignant GIST. The tumor was composed of short fascicles of spindle cells. In addition to the presence of tumor giant cells, the tumor also demonstrated many osteoclast-like giant cells, a feature that has not been previously described in the literature. These giant cells expressed histiocytic markers CD68 and alpha(1)-antitrypsin but not c-Kit, a marker for GISTs. Electron microscopy showed no features of smooth muscle differentiation in the giant cells. The possible origin of the osteoclast-like giant cells is discussed in the context of immunohistochemical and ultrastructural characteristics.


Assuntos
Neoplasias Gastrointestinais/patologia , Osteoclastos/patologia , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos
10.
Diagn Cytopathol ; 26(3): 174-80, 2002 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-11892024

RESUMO

A definitive diagnosis of clear-cell sarcoma of soft parts (CCSSP) is possible by fine-needle aspiration (FNA) biopsy alone. The aspirates are markedly cellular, consisting predominantly of discohesive cells but also of cohesive cells. The cytoplasm is eosinophilic and eccentric. The nuclei are round and contain macronucleoli. CCSSP should be considered when FNA of a soft-tissue tumor shows uncharacteristically high cellularity and relatively uniform cells with macronucleoli. Cohesion of some tumor cells does not rule out CCSSP. Melanin pigment and cytoplasmic clearing are infrequent and not necessary for the diagnosis. Sufficient material should always be procured for immunohistochemical studies on the cell block. Seven other cases are found in the literature, all correctly diagnosed by FNA. Although it is rare, CCSSP is a highly malignant tumor that can be diagnosed readily by FNA without resorting to incisional biopsy.


Assuntos
Sarcoma de Células Claras/patologia , Neoplasias de Tecidos Moles/patologia , Adulto , Antígenos de Neoplasias , Biomarcadores Tumorais/análise , Biópsia por Agulha , Núcleo Celular/patologia , Citoplasma/ultraestrutura , Evolução Fatal , Células Gigantes/patologia , Humanos , Técnicas Imunoenzimáticas , Masculino , Antígenos Específicos de Melanoma , Proteínas de Neoplasias/análise , Proteínas S100/análise , Sarcoma de Células Claras/química , Sarcoma de Células Claras/ultraestrutura , Neoplasias de Tecidos Moles/química , Neoplasias de Tecidos Moles/ultraestrutura
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