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1.
Usha Patel Manish Pandey Sadhana Kannan Tanuja A. Samant Poonam Gera Neha Mittal Swapnil Rane Asawari Patil Vanita Noronha Amit Joshi Vijay M. Patil Kumar Prabhash Manoj B. Mahimkar 《British journal of cancer》2020,123(12):1757
Background Anti-EGFR-based therapies have limited success in HNSCC patients. Predictive biomarkers are greatly needed to identify the patients likely to be benefited from these targeted therapies. Here, we present the prognostic and predictive association of biomarkers in HPV-negative locally advanced (LA) HNSCC patients.Methods Treatment-naive tumour tissue samples of 404 patients, a subset of randomised Phase 3 trial comparing cisplatin radiation (CRT) versus nimotuzumab plus cisplatin radiation (NCRT) were analysed to evaluate the expression of HIF1α, EGFR and pEGFR by immunohistochemistry and EGFR gene copy change by FISH. Progression-free survival (PFS), locoregional control (LRC) and overall survival (OS) were estimated by Kaplan–Meier method. Hazard ratios were estimated by Cox proportional hazard models.Results Baseline characteristics of the patients were balanced between two treatment groups (CRT vs NCRT) and were representative of the trial cohort. The median follow-up was of 39.13 months. Low HIF1α was associated with better PFS [HR (95% CI) = 0.62 (0.42–0.93)], LRC [HR (95% CI) = 0.56 (0.37–0.86)] and OS [HR (95% CI) = 0.63 (0.43–0.93)] in the CRT group. Multivariable analysis revealed HIF1α as an independent negative prognostic biomarker. For patients with high HIF1α, NCRT significantly improved the outcomes [PFS:HR (95% CI) = 0.55 (0.37–0.82), LRC:HR (95% CI) = 0.55 (0.36–0.85) and OS:HR (95% CI) = 0.54 (0.36–0.81)] compared to CRT. While in patients with low HIF1α, no difference in the clinical outcomes was observed between treatments. Interaction test suggested a predictive value of HIF1α for OS (P = 0.008).Conclusions High HIF1α expression is a predictor of poor clinical response to CRT in HPV-negative LA-HNSCC patients. These patients with high HIF1α significantly benefited with the addition of nimotuzumab to CRT.Clinical trial registration Registered with the Clinical Trial Registry of India (Trial registration identifier—CTRI/2014/09/004980).Subject terms: Tumour biomarkers, Head and neck cancer, Tumour biomarkers, Head and neck cancer, Predictive markers 相似文献
2.
Stress Testing Versus CT Angiography in Patients With Diabetes and Suspected Coronary Artery Disease
Abhinav Sharma Adrian Coles Nishant K. Sekaran Neha J. Pagidipati Michael T. Lu Daniel B. Mark Kerry L. Lee Hussein R. Al-Khalidi Udo Hoffmann Pamela S. Douglas 《Journal of the American College of Cardiology》2019,73(8):893-902
Background
The optimal noninvasive test (NIT) for patients with diabetes and stable symptoms of coronary artery disease (CAD) is unknown.Objectives
The purpose of this study was to assess whether a diagnostic strategy based on coronary computed tomographic angiography (CTA) is superior to functional stress testing in reducing adverse cardiovascular (CV) outcomes (CV death or myocardial infarction [MI]) among symptomatic patients with diabetes.Methods
PROMISE (Prospective Multicenter Imaging Study for Evaluation of Chest Pain) was a randomized trial evaluating an initial strategy of CTA versus functional testing in stable outpatients with symptoms suggestive of CAD. The study compared CV outcomes in patients with diabetes (n = 1,908 [21%]) and without diabetes (n = 7,058 [79%]) based on their randomization to CTA or functional testing.Results
Patients with diabetes (vs. without) were similar in age (median 61 years vs. 60 years) and sex (female 54% vs. 52%) but had a greater burden of CV comorbidities. Patients with diabetes who underwent CTA had a lower risk of CV death/MI compared with functional stress testing (CTA: 1.1% [10 of 936] vs. stress testing: 2.6% [25 of 972]; adjusted hazard ratio: 0.38; 95% confidence interval: 0.18 to 0.79; p = 0.01). There was no significant difference in nondiabetic patients (CTA: 1.4% [50 of 3,564] vs. stress testing: 1.3% [45 of 3,494]; adjusted hazard ratio: 1.03; 95% confidence interval: 0.69 to 1.54; p = 0.887; interaction term for diabetes p value = 0.02).Conclusions
In diabetic patients presenting with stable chest pain, a CTA strategy resulted in fewer adverse CV outcomes than a functional testing strategy. CTA may be considered as the initial diagnostic strategy in this subgroup. (PROspective Multicenter Imaging Study for Evaluation of Chest Pain [PROMISE]; NCT01174550) 相似文献3.
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Duct-associated lymphoid tissue (DALT) of minor salivary glands and mucosal immunity. 总被引:3,自引:0,他引:3
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Minor salivary glands (MSG) play a substantial role in the secretory immunoglobulin A (sIgA)-mediated immunity of the oral cavity. There are two possibilities for the induction of this immunity: (i) an explicitly local antigenic stimulus, or (ii) a remote stimulus as part of the so-called 'common mucosal immune system'. This communication is an attempt to consolidate available evidence in support of both possibilities and to address the former in detail. Although there is strong circumstantial evidence supporting the feasibility of MSG functioning as a part of the common mucosal immune system, direct experimental evidence is yet to emerge. On the other hand, there is increasing structural and physiological evidence in support of MSG serving as a local immunological organ. The purely local response is attributed to the presence of MSG duct-associated lymphoid tissue (DALT), which is comparable to gut- or bronchial-associated lymphoid tissue (GALT or BALT) in origin, tissue organization and function. DALT is accessible to oral antigens by retrograde passage through MSG ducts. Repeated topical antigenic challenging via the oral mucosa may result in the appearance of interacinar plasma cells carrying specific homologous antibodies in MSG. Gut or enteric priming of the same antigen, by passing the oral mucosa by gastric intubation, need not evoke a remote immune response in MSG. Since DALT is more likely to occur in healthy, young growing individuals, who are less likely to undergo bioptic examination of MSG, it has not yet been documented in humans. The physiologically induced DALT is apt to be confused with focal accumulations of lymphoid tissue in pathologically altered MSG, as a consequence of local and some systemic autoimmune diseases. An attempt is made to demarcaate healthy and pathological MSG on the basis of currently available clinical, serological, immunological and genetic evidence. 相似文献
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R Nair K Prabhash M Sengar A Bakshi S Gujral S Gupta P Parikh 《Annals of oncology》2007,18(7):1243-1245
BACKGROUND: Various malignancies and cytotoxic chemotherapy have been proposed to increase the risk of reactivation of tuberculosis. Available literature to support this observation is still conflicting. There is scarcity of data from countries with rampant tubercular infection, such as India, in this regard. DESIGN AND METHODS: In the present retrospective analysis, patients with high-grade non-Hodgkin's lymphoma with past history of tuberculosis and have had adequate antitubercular therapy were identified from a Lymphoma Group study. These patients were followed up during cytotoxic chemotherapy and later to assess the risk of reactivation. RESULTS: A cohort of eight patients with past history of tuberculosis was selected from 141 patients of high-grade non-Hodgkin's lymphoma. The median age was 33.5 years (range, 24-53 years). Median duration between completion of antitubercular treatment and diagnosis of lymphoma was 5 years (range, 1.5-10 years). All patients received cyclical cytotoxic chemotherapy. The median duration of follow up after completion of chemotherapy was 5 years (range, 10 months to 5 years). None of these patients developed reactivation of tuberculosis. CONCLUSION: Cyclical chemotherapy for non-Hodgkin's lymphoma does not lead to reactivation of tuberculosis. 相似文献
9.
A Abraham M G Nair R L Kisliuk Y Gaumont J Galivan 《Journal of medicinal chemistry》1990,33(2):711-717
Representative examples of folate and antifolate poly-gamma-glutamyl metabolites were synthesized via the [(9-fluorenylmethoxy)oxy]carbonyl (Fmoc) chemistry using the KH polyamide resin. Polyglutamate yields were consistently better in all cases compared to the previous Merrifield method, and the crude products were obtained in greater than 85% purity. The symmetrical anhydride (7) derived from alpha-tert-butyl N-Fmoc-L-glutamate (6) was used for the initial coupling of the first glutamate residue to the KH resin and also for subsequent chain elongation. The alpha-tert-butyl protective groups were not labile under the conditions used for the cleavage of the finished peptide from the resin. A series of poly-gamma-glutamyl metabolites of methotrexate (MTX) with a chain length ranging from two to five glutamyl residues were synthesized and coupled with poly(L-lysine) having an average molecular weight of 27,000 and 52,000. Each conjugate was tested for its ability to inhibit the growth of wild type (H35) and MTX transport resistant (H35R) strains of hepatoma cells in culture, the latter having a 100-fold reduced sensitivity to MTX. 4-Amino-4-deoxy-N10-methylpteroylglutamyl-gamma-glutamylpoly (L-lysine) conjugate [MTX(G2)-poly-L-Lys-52000] and MTX(G4)-poly-L-Lys-52000 were among the most active (I50 = 8.0 and 10 nM against H35 cells) MTX-polylysines synthesized to date, and they were somewhat more inhibitory to the transport resistant cells. MTX(G5)-poly-L-Lys-52000 was approximately 1000 times more effective than MTX(G5)-poly-D-Lys-52000 in inhibiting the growth of H35R hepatoma cells in culture, indicating that internal cleavage of the gamma-glutamate chain of the conjugate with subsequent release of MTX or shorter chain polyglutamates of MTX is unlikely to be an important determinant of MTX-polyglutamate polylysine cytotoxicity. The results indicate that MTX-polyglutamate poly(L-lysine) conjugates are taken up by the cells independently of MTX and probably via endocytosis. 相似文献
10.
Norethisterone enanthate (NET-En), an established intramuscular long-acting contraceptive agent, has previously been shown to be effective in inhibiting fertility in two rodent species even 4 days after oral ingestion. Pharmacokinetics of NET and NET-En were studied after oral and intramuscular doses in two animal species and a few women. The results suggest that the NET-En was absorbed within a day in all the species after oral dose. The estimates of relative bioavailability ranged from 13 to 51% in rabbits, monkeys, and women. The elimination half-life was 5–10 days. The presence of the active component, NET, in the circulation over the experimental period of 15 days suggests that NET-En could be useful as a long-acting oral pill. The suppression of progesterone levels during the luteal phase of menstrual cycle in women also supports this finding. 相似文献