Session XII Male contraception

Session XII Male contraception     

Esophageal cancer in Kashmir — an assessment

Conclusion Kashmir, with its culturally distinct population with uniform and stable dietary habits, provides an interesting field area for studying the relevance of diet in human esophageal carcinogenesis. In the absence of several features of life-style normally associated with increased incidence of the disease, the local food habits appear to be critical factors in the etiology of this cancer in Kashmir. Evidence from our preliminary studies shows a considerable dietary exposure to preformed N-nitroso compounds in the local population. In addition, the potential endogenous formation of N-nitroso compounds, caused by high precursor contents in certain foodstuffs, enhances the relevance of these compounds as possible risk factors for esophageal and other gastrointestinal cancers in this region. The quantitative assessment of total human exposure to N-nitroso compounds and their exact significance to the high cancer incidence in Kashmir requires carefully planned environmental monitoring and prospective epidemiological studies.The Journal of Cancer Research and Clinical Oncology publishes in loose succession Editorials and Guest editorials on current and/or controversial problems in experimental and clinical oncology. These contributions represent exclusively the personal opinion of the author     

Identifying gaps in COVID-19 health equity data reporting in Canada using a scorecard approach

ObjectiveTo assess health equity-oriented COVID-19 reporting across Canadian provinces and territories, using a scorecard approach.MethodsA scan was performed of provincial and territorial reporting of five data elements (cumulative totals of tests, cases, hospitalizations, deaths, and population size) across three units of aggregation (province or territory level, health regions, and local areas) (15 “overall” indicators), and for four vulnerable settings (long-term care and detention facilities, schools, and homeless shelters) and eight social markers (age, sex, immigration status, race/ethnicity, healthcare worker status, occupational sector, income, and education) (180 “equity-related” indicators) as of December 31, 2020. Per indicator, one point was awarded if case-delimited data were released, 0.7 points if only summary statistics were reported, and 0 if neither was provided. Results were presented using a scorecard approach.ResultsOverall, information was more complete for cases and deaths than for tests, hospitalizations, and population size denominators needed for rate estimation. Information provided on jurisdictions and their regions, overall, tended to be more available (average score of 58%, “D”) than that for equity-related indicators (average score of 17%, “F”). Only British Columbia, Alberta, and Ontario provided case-delimited data, with Ontario and Alberta providing case information for local areas. No jurisdiction reported on outcomes according to patients’ immigration status, race/ethnicity, income, or education. Though several provinces reported on cases in long-term care facilities, only Ontario and Quebec provided detailed information for detention facilities and schools, and only Ontario reported on cases within homeless shelters and across occupational sectors.ConclusionOne year into the pandemic, socially stratified reporting for COVID-19 outcomes remains sparse in Canada. However, several “best practices” in health equity-oriented reporting were observed and set a relevant precedent for all jurisdictions to follow for this pandemic and future ones.Supplementary InformationThe online version contains supplementary material available at 10.17269/s41997-021-00496-6.     

Evaluation of rapid radiometric method for drug susceptibility testing of Mycobacterium tuberculosis.

A total of 106 isolates of Mycobacterium tuberculosis were tested for drug susceptibility by the conventional 7H11 plate method and by a new rapid radiometric method using special 7H12 liquid medium with 14C-labeled substrate. Results obtained by the two methods were compared for rapidity, sensitivity, and specificity of the new test method. There was 98% overall agreement between the results obtained by the two methods. Of a total of 424 drug tests, only 8 drug results did not agree, mostly in the case of streptomycin. This new procedure was found to be rapid, with 87% of the tests results reportable within 4 days and 98% reportable within 5 days as compared to the usual 3 weeks required with the conventional indirect susceptibility test method. The results of this preliminary study indicate that the rapid radiometric method seems to have the potential for routine laboratory use and merits further investigations.     

Perinatal asphyxia in infants of insulin-dependent diabetic mothers

Infants of diabetic mothers are thought to be at risk for perinatal asphyxia. We hypothesized that the following are significant risk factors for perinatal asphyxia: poor third-trimester glycemic control, diabetic vascular disease (nephropathy, retinopathy) appearing in pregnancy, pregnancy-associated hypertension, smoking, prematurity, fetal macrosomia, and maternal hyperglycemia and hypoglycemia within 6 hours preceding delivery. We prospectively studied 162 infants born to 149 diabetic mothers (White classes B through R-T). Perinatal asphyxia was defined clinically as fetal distress during labor (late decelerations, persistent fetal bradycardia, or both), 1-minute Apgar score less than or equal to 6, or intrauterine fetal death. Forty-four infants (26.7%) had perinatal asphyxia. The presence of perinatal asphyxia did not correlate with third-trimester glycemic control, pregnancy-associated hypertension, smoking, fetal macrosomia, or maternal hypoglycemia before delivery, but it did correlate significantly with nephropathy appearing in pregnancy, maternal hyperglycemia before delivery, and prematurity. We speculate that (1) the appearance of diabetic vasculopathy (nephropathy) during pregnancy is accompanied by placental vascular disease and subsequently by fetal compromise and (2) in pregnancy complicated by diabetes, maternal and subsequently fetal hyperglycemia before delivery leads to fetal hypoxemia.     

Distinguishing true from false positives in genomic studies: p values

Distinguishing true from false positive findings is a major challenge in human genetic epidemiology. Several strategies have been devised to facilitate this, including the positive predictive value (PPV) and a set of epidemiological criteria, known as the “Venice” criteria. The PPV measures the probability of a true association, given a statistically significant finding, while the Venice criteria grade the credibility based on the amount of evidence, consistency of replication and protection from bias. A vast majority of journals use significance thresholds to identify the true positive findings. We studied the effect of p value thresholds on the PPV and used the PPV and Venice criteria to define usable thresholds of statistical significance. Theoretical and empirical analyses of data published on AlzGene show that at a nominal p value threshold of 0.05 most “positive” findings will turn out to be false if the prior probability of association is below 0.10 even if the statistical power of the study is higher than 0.80. However, in underpowered studies (0.25) with a low prior probability of 1 × 10^?3, a p value of 1 × 10^?5 yields a high PPV (>96 %). Here we have shown that the p value threshold of 1 × 10^?5 gives a very strong evidence of association in almost all studies. However, in the case of a very high prior probability of association (0.50) a p value threshold of 0.05 may be sufficient, while for studies with very low prior probability of association (1 × 10^?4; genome-wide association studies for instance) 1 × 10^?7 may serve as a useful threshold to declare significance.