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1.
Ian A. Chisholm Stephen M. Drance Teresa To 《Albrecht von Graefes Archiv fur klinische und experimentelle Ophthalmologie》1989,227(2):110-113
Visual-field areas to a I2e stimulus were measured planimetrically using an X-Y digitizer and a computer program. Sampling of normal subjects and patients suspected of having glaucoma was done at two points in time. Calculations of eye-wall stress were done using ultrasonic data and intra-ocular pressure (IOP) measurements from patient records. For those suspected of having glaucoma who developed chronic open-angle glaucoma (COAG), the time of transition was the second point in time. The visual field area was regressed against patient age at the two points in time. No difference in the regression slopes was found for the normal subjects and unchanged patients. The patients who did develop glaucoma were significantly different. The mean annual rate of visual-field change (rate of decay) was calculated and found to be 28.5 mm2/year for the normals, 153.5 mm2/year for the suspects, and 376.4 mm2/year for those patients who developed glaucoma. The rate of visual-field decay only correlated with patient age (P = 0.03) and eye-wall stress (P < 0.01) in the patients who developed glaucoma. 相似文献
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We investigated 10 unrelated Chinese patients with type 2 Gaucher disease and performed ex vivo expression for the novel mutations to characterize their functional defects. These patients were diagnosed by enzymatic assays and clinicopathologic features over the past five years in a national centre in China. Genomic DNA was sequenced by a two-stage PCR approach for mutations in the functional GBA gene. Novel mutations were expressed with baculovirus-transfected Sf21 cells. Six novel mutations were found (in traditional nomenclature): P122L, Y363C, N382K, L383R, L385P, and M416V. Review of reported mutations indicated clustering of type 2 mutations in three regions of the GBA gene. Expression of novel mutations revealed that the enzyme defect could arise from one of two mechanisms: loss of catalytic activity (Y363C and M416V) or enzyme instability (P122L and N382K). 相似文献
5.
Early interleukin 4-dependent response can induce airway hyperreactivity before development of airway inflammation in a mouse model of asthma 总被引:3,自引:0,他引:3
To Y Dohi M Tanaka R Sato A Nakagome K Yamamoto K 《Laboratory investigation; a journal of technical methods and pathology》2001,81(10):1385-1396
In experimental models of bronchial asthma with mice, airway inflammation and increase in airway hyperreactivity (AHR) are induced by a combination of systemic sensitization and airway challenge with allergens. In this report, we present another possibility: that systemic antigen-specific sensitization alone can induce AHR before the development of inflammation in the airway. Male BALB/c mice were sensitized with ovalbumin (OVA) by a combination of intraperitoneal injection and aerosol inhalation, and various parameters for airway inflammation and hyperreactivity were sequentially analyzed. Bronchial response measured by a noninvasive method (enhanced pause) and the eosinophil count and interleukin (IL)-5 concentration in bronchoalveolar lavage fluid (BALF) gradually increased following the sensitization, and significant increase was achieved after repeated OVA aerosol inhalation along with development of histologic changes of the airway. In contrast, AHR was already significantly increased by systemic sensitization alone, although airway inflammation hardly developed at that time point. BALF IL-4 concentration and the expression of IL-4 mRNA in the lung reached maximal values after the systemic sensitization, then subsequently decreased. Treatment of mice with anti-IL-4 neutralizing antibody during systemic sensitization significantly suppressed this early increase in AHR. In addition, IL-4 gene-targeted mice did not reveal this early increase in AHR by systemic sensitization. These results suggest that an immune response in the lung in an early stage of sensitization can induce airway hyperreactivity before development of an eosinophilic airway inflammation in BALB/c mice and that IL-4 plays an essential role in this process. If this early increase in AHR does occur in sensitized human infants, it could be another therapeutic target for early prevention of the future onset of asthma. 相似文献
6.
Use of antisera to epithelial membrane antigen for the cytodiagnosis of malignancy in serous effusions. 总被引:4,自引:5,他引:4 下载免费PDF全文
A To D V Coleman D P Dearnaley M G Ormerod K Steele A M Neville 《Journal of clinical pathology》1981,34(12):1326-1332
A new human antigen, designated epithelial membrane antigen (EMA), has recently been described on surface membranes of a wide variety of normal epithelium but not on connective tissue cells. The antigen is only weakly expressed on normal or reactive mesothelium. Increased expression of the antigen has been observed in most neoplasms of epithelial origin and in malignant mesothelioma. We have investigated the possibility of using this difference in the expression of the antigen to distinguish between mesothelial cells and malignant cells in cytological smears of serous effusions. This distinction cannot always be made on morphological grounds alone and problems of differential diagnosis are encountered in about 15% of all specimens of serous effusions sent for cytological examination. Using antisera to EMA we have applied an indirect immunoalkaline phosphatase technique to alcohol-fixed smears prepared from serous effusions and have found that intense staining of the antigen is confined to effusions from patients in whom there is either clinical or cytological evidence of malignancy. The technique proved to be especially useful in cytologically equivocal cases, where there were problems of differential diagnosis. 相似文献
7.
Chan PK To KF Lo AW Cheung JL Chu I Au FW Tong JH Tam JS Sung JJ Ng HK 《Journal of medical virology》2004,74(1):1-7
Severe acute respiratory syndrome coronavirus (SARS-CoV) can produce gastrointestinal symptoms. The intestinal tract is the only extrapulmonary site where viable viruses have been detected. This study examined seven established human intestinal cell lines, DLD-1, HCT-116, HT-29, LoVo, LS-180, SW-480 and SW-620, for their permissiveness to SARS-CoV infection. The results showed that only LoVo cells were permissive to SARS-CoV infection as evident by positive findings from indirect immunofluorescence staining for intracellular viral antigens, in situ hybridization for intracellular viral RNA, and electron microscopy for intracellular viral particles. In contrast to Vero cells, SARS-CoV did not produce cytopathic effects on LoVo cells. However, LoVo cells were found to be highly permissive for productive infection with a high viral titre (>3 x 10(7) viral copies/ml) produced in culture supernatant following a few days of incubation. SARS-CoV established a stable persistent chronic infection that could be maintained after multiple passages. Being a cell line of human origin, LoVo cells could be a useful in vitro model for studying the biology and persistent infection of SARS-CoV. Our results on the expression of angiotensin-converting enzyme 2 (ACE2), a recently identified cellular receptor for SARS-CoV, in these cell lines indicated that it might not be the sole determinant for cells to be susceptible to SARS-CoV infection. 相似文献
8.
Pulmonary pathological features in coronavirus associated severe acute respiratory syndrome (SARS) 总被引:5,自引:0,他引:5
Tse GM To KF Chan PK Lo AW Ng KC Wu A Lee N Wong HC Mak SM Chan KF Hui DS Sung JJ Ng HK 《Journal of clinical pathology》2004,57(3):260-265
BACKGROUND: Severe acute respiratory syndrome (SARS) became a worldwide outbreak with a mortality of 9.2%. This new human emergent infectious disease is dominated by severe lower respiratory illness and is aetiologically linked to a new coronavirus (SARS-CoV). METHODS: Pulmonary pathology and clinical correlates were investigated in seven patients who died of SARS in whom there was a strong epidemiological link. Investigations include a review of clinical features, morphological assessment, histochemical and immunohistochemical stainings, ultrastructural study, and virological investigations in postmortem tissue. RESULTS: Positive viral culture for coronavirus was detected in most premortem nasopharyngeal aspirate specimens (five of six) and postmortem lung tissues (two of seven). Viral particles, consistent with coronavirus, could be detected in lung pneumocytes in most of the patients. These features suggested that pneumocytes are probably the primary target of infection. The pathological features were dominated by diffuse alveolar damage, with the presence of multinucleated pneumocytes. Fibrogranulation tissue proliferation in small airways and airspaces (bronchiolitis obliterans organising pneumonia-like lesions) in subpleural locations was also seen in some patients. CONCLUSIONS: Viable SARS-CoV could be isolated from postmortem tissues. Postmortem examination allows tissue to be sampled for virological investigations and ultrastructural examination, and when coupled with the appropriate lung morphological changes, is valuable to confirm the diagnosis of SARS-CoV, particularly in clinically unapparent or suspicious but unconfirmed cases. 相似文献
9.
K.K.W. To C.C.Y. Yip C.Y.W. Lai C.K.H. Wong D.T.Y. Ho P.K.P. Pang A.C.K. Ng K.-H. Leung R.W.S. Poon K.-H. Chan V.C.C. Cheng I.F.N. Hung K.-Y. Yuen 《Clinical microbiology and infection》2019,25(3):372-378
Objectives
Automated point-of-care molecular assays have greatly shortened the turnaround time of respiratory virus testing. One of the major bottlenecks now lies at the specimen collection step, especially in a busy clinical setting. Saliva is a convenient specimen type that can be provided easily by adult patients. This study assessed the diagnostic validity, specimen collection time and cost associated with the use of saliva.Methods
This was a prospective diagnostic validity study comparing the detection rate of respiratory viruses between saliva and nasopharyngeal aspirate (NPA) among adult hospitalized patients using Xpert® Xpress Flu/RSV. The cost and time associated with the collection of saliva and nasopharyngeal specimens were also estimated.Results
Between July and October 2017, 214 patients were recruited. The overall agreement between saliva and NPA was 93.3% (196/210, κ 0.851, 95% CI 0.776–0.926). There was no significant difference in the detection rate of respiratory viruses between saliva and NPA (32.9% (69/210) versus 35.7% (75/210); p 0.146). The overall sensitivity and specificity were 90.8% (81.9%–96.2%) and 100% (97.3%–100%), respectively, for saliva, and were 96.1% (88.9%–99.2%) and 98.5% (94.7%–99.8%), respectively, for NPA. The time and cost associated with the collection of saliva were 2.26-fold and 2.59-fold lower, respectively, than those of NPA.Conclusions
Saliva specimens have high sensitivity and specificity in the detection of respiratory viruses by an automated multiplex Clinical Laboratory Improvement Amendments-waived point-of-care molecular assay when compared with those of NPA. The use of saliva also reduces the time and cost associated with specimen collection. 相似文献10.
Case report: human herpesvirus 7 associated fatal encephalitis in a peripheral blood stem cell transplant recipient 总被引:2,自引:0,他引:2
Chan PK Chik KW To KF Li CK Shing MM Ng KC Yuen PM Cheng AF 《Journal of medical virology》2002,66(4):493-496
Previous studies have suggested a neuroinvasive and neuropersistent potential of human herpesvirus 7 (HHV-7). In this report, a case of fatal encephalitis is described and its association with HHV-7 infection is discussed. An 8-year-old girl received a peripheral blood stem cell transplant for relapsed acute lymphoblastic leukaemia. The post-transplant period was uneventful and a course of intrathecal chemotherapy was given on Day-30. On Day-41, she developed acute encephalopathy with diplopia and nystagmus. She ran a rapid downhill course and succumbed despite antiviral treatment. The only positive pathological finding was the multiple microscopic foci of haemorrhage associated with neuronal degeneration detected in the brain stem. All microbiological investigations were negative, except for the presence of HHV-7 DNA in cerebrospinal fluid and brain stem tissue samples. 相似文献