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81.
Jessica Irving Rashmi Patel Dominic Oliver Craig Colling Megan Pritchard Matthew Broadbent Helen Baldwin Daniel Stahl Robert Stewart Paolo Fusar-Poli 《Schizophrenia bulletin》2021,47(2):405
BackgroundUsing novel data mining methods such as natural language processing (NLP) on electronic health records (EHRs) for screening and detecting individuals at risk for psychosis. MethodThe study included all patients receiving a first index diagnosis of nonorganic and nonpsychotic mental disorder within the South London and Maudsley (SLaM) NHS Foundation Trust between January 1, 2008, and July 28, 2018. Least Absolute Shrinkage and Selection Operator (LASSO)-regularized Cox regression was used to refine and externally validate a refined version of a five-item individualized, transdiagnostic, clinically based risk calculator previously developed (Harrell’s C = 0.79) and piloted for implementation. The refined version included 14 additional NLP-predictors: tearfulness, poor appetite, weight loss, insomnia, cannabis, cocaine, guilt, irritability, delusions, hopelessness, disturbed sleep, poor insight, agitation, and paranoia. ResultsA total of 92 151 patients with a first index diagnosis of nonorganic and nonpsychotic mental disorder within the SLaM Trust were included in the derivation (n = 28 297) or external validation (n = 63 854) data sets. Mean age was 33.6 years, 50.7% were women, and 67.0% were of white race/ethnicity. Mean follow-up was 1590 days. The overall 6-year risk of psychosis in secondary mental health care was 3.4 (95% CI, 3.3–3.6). External validation indicated strong performance on unseen data (Harrell’s C 0.85, 95% CI 0.84–0.86), an increase of 0.06 from the original model. ConclusionsUsing NLP on EHRs can considerably enhance the prognostic accuracy of psychosis risk calculators. This can help identify patients at risk of psychosis who require assessment and specialized care, facilitating earlier detection and potentially improving patient outcomes. 相似文献
82.
Sajini Kuruppu Marvey Ghani Megan Pritchard Matthew Harris Ruwan Weerakkody Robert Stewart Gayan Perera 《European psychiatry》2021,64(1)
BackgroundPatients with depression are more susceptible to cardiovascular illness including vascular surgeries. However, health outcomes after vascular surgery among patients with depression is unknown. This study aimed to investigate associations of depression with post-operative health outcomes for vascular surgical patients.MethodsA retrospective observational study was conducted using data from a large mental healthcare provider and linked national hospitalization data for the same south London geographic catchment. OPCS-4 codes were used to identify vascular procedures. Health outcomes were compared between those with/without depression including length of hospital stay (LOS), inpatient mortality, and 30 day emergency hospital readmissions. Predictors of these health outcomes were also assessed.ResultsVascular surgery was received by 9,267 patients, including 446 diagnosed with depression. Patients with depression had a higher risk of emergency admission for vascular surgery (odds ratio [OR] 1.28; 1.03, 1.59), longer index LOS (IRR 1.38; 1.33–1.42), and a higher risk of 30-day emergency readmission (OR 1.82; 1.35–2.47). Patients with depression had higher inpatient mortality after adjustment for sociodemographic status (1.51; 1.03, 2.23) but not on full adjustment, and had longer emergency readmission LOS (1.13; 1.04, 1.22) after adjustment for sociodemographic factors and cardiovascular disease. Correlates of vascular surgery hospitalization among patients with depression included admission through emergency route for longer LOS, inpatient mortality, and 30-day hospital readmission.ConclusionPatients with depression undergoing vascular surgery have substantially poorer health outcomes. Screening for depression prior to surgery might be indicated to target preventative measures. 相似文献
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Amplification of genes encoding human myeloid membrane antigens after DNA-mediated gene transfer 总被引:2,自引:0,他引:2
Spontaneous amplification of genes encoding two different human myeloid surface antigens was observed after DNA-mediated gene transfer of cellular DNA from the human myeloid cell line HL-60 into NIH-3T3 mouse fibroblasts. Transformed recipient cells with highly amplified expression of either of two donor membrane polypeptides, gp150 or p67, were isolated with a fluorescence-activated cell sorter (FACS), using monoclonal antibodies specific for human myeloid cells. Immunoprecipitation of enzymatically radioiodinated polypeptides from the surface of transformed NIH-3T3 cells confirmed that expression of these proteins was amplified tenfold to 20-fold in comparison to their expression on human myeloid cell lines. The cellular DNA of cloned secondary and tertiary transformants expressing high levels of gp150 and p67 contained amplified sets of DNA restriction fragments that hybridized with human repetitive DNA sequences. Cytogenetic analysis of subclones overexpressing gp150 revealed extrachromosomal double minutes (DMs), whose presence correlated with the unstable expression of the membrane polypeptide. Human sequences in gp150-positive clones did not localize to chromosomes, consistent with their association with extrachromosomal DMs. By contrast, p67-positive subclones stably expressed the antigen, and in situ hybridization to metaphase spreads demonstrated that amplified human DNA sequences were integrated into a specific marker chromosome. Cytogenetic analysis of the parental NIH- 3T3 subclone used in these studies disclosed DMs in a low percentage of metaphases, suggesting that the recipient cells have a propensity for amplifying donor DNA. 相似文献
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RD Vaithilingam SH Safii NA Baharuddin LP Karen‐Ng R Saub F Ariffin H Ramli A Sharifuddin MFH Hidayat R Raman YK Chan NA Rani RA Rahim N Shahruddin SC Cheong PM Bartold RB Zain 《Oral diseases》2015,21(1):e62-e69
Periodontal bio‐repositories, which allow banking of clinically validated human data and biological samples, provide an opportunity to derive biomarkers for periodontal diagnosis, prognosis and therapeutic activities which are expected to improve patient management. This article presents the establishing of the Malaysian Periodontal Database and Biobank System (MPDBS) which was initiated in 2011 with the aim to facilitate periodontal research. Partnerships were established with collaborating centres. Policies on specimen access, authorship and acknowledgement policies were agreed upon by all participating centres before the initiation of the periodontal biobank. Ethical approval for the collection of samples and data were obtained from institutional ethics review boards. A broad‐based approach for informed consent was used, which covered areas related to quality of life impacts, genetics and molecular aspects of periodontal disease. Sample collection and processing was performed using a standardized protocol. Biobanking resources such as equipment and freezers were shared with the Malaysian Oral Cancer Database and Tissue Bank System (MOCDTBS). In the development of the MPDBS, challenges that were previously faced by the MOCDTBS were considered. Future challenges in terms of ethical and legal issues will be faced when international collaborations necessitate the transportation of specimens across borders. 相似文献
87.
This study describes the immune responses of two defined badger populations; one from East Sussex and another from Staffordshire. The mean in vitro lymphoproliferative response, of all infected badgers from both areas, to Glaxo BCG, was significantly greater than that of healthy animals. The infected badgers had significantly higher antibody levels against mycobacterial antigens, especially New Tuberculin, than did the healthy animals. All the healthy and tuberculous badgers from the Staffordshire area were invariably unreactive to the various preparations used for skin-testing. However, in the East Sussex area, positive reactions were obtained in 10 out of 37 healthy and 7 out of 10 infected animals. This is the first account of positive skin tests in free living badgers. These results support the concept that badgers infected with bovine tubercle bacilli pass through an immunological spectrum throughout much of which they are unlikely to be important sources of infection. In the early stages, tubercle bacilli are excreted from infected wounds, whereas in the later stages, failure of cell-mediated immunity results in excretion of tubercle bacilli from other sites and the badger becomes a potent source of infection. 相似文献
88.
Guy Betts Helen Valentine Sue Pritchard Richard Swindell Victoria Williams Shethah Morgan Ewen A. Griffiths Ian Welch Catharine West Christopher Womack 《Virchows Archiv : an international journal of pathology》2014,464(2):145-156
Receptor tyrosine kinase pathways are potential therapeutic targets in gastric adenocarcinoma patients. We evaluated HER2 and cMet protein expression, and FGFR2 gene amplification to assess their prognostic significance, and downstream mediators pS6 and pERK for their potential utility as pharmacodynamic biomarkers in patients with gastric adenocarcinoma. Tissue microarrays were constructed from resection samples of 184 patients who underwent surgery for gastric/gastro-oesophageal junction adenocarcinoma. Tissue cores were obtained from the tumour body (TB), luminal surface (LS) and invasive edge (IE), and immunohistochemical and fluorescence in situ hybridisation (FGFR2) analysis was performed. FGFR2 amplification was identified in 2 % of cases and associated with worse survival (P?=?0.005). HER2 overexpression was observed in 10 % of cases and associated with increased survival (P?=?0.041). cMet overexpression was observed in 4 % of cases and associated with worse survival (P?<?0.001). On multivariate analysis, only cMet retained significance (P?=?0.006). pS6 and pERK expression were observed in 73 % and 30 % of tumours, respectively, with no association with survival. HER2 (P?=?0.004) and pERK (P?=?0.001) expression differed between tumour regions with HER2 expression increased in the LS compared with the TB and IE. These findings confirm subpopulations in gastric adenocarcinoma with poor outcome that may benefit from specific therapeutic strategies. However, we found heterogeneous HER2, pS6 and pERK overexpression, which presents challenges for their use as predictive biomarkers in gastric biopsies. The potential downstream pharmacodynamic markers pS6 and pERK were expressed across tumour regions, providing evidence that resections and biopsies would yield comparative results in clinical trials. 相似文献
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