51 research outputs found
Colonic perianastomotic carcinogenesis in an experimental model
BACKGROUND: To examine the effect of anastomosis on experimental carcinogenesis in the colon of rats. METHODS: Forty-three 10-week-old male and female Sprague-Dawley rats were operated on by performing an end-to-side ileorectostomy. Group A:16 rats received no treatment. Group B: 27 rats received 18 subcutaneous injections weekly at a dose of 21 mg/kg wt of 1–2 dimethylhydrazine (DMH), from the eighth day after the intervention. Animals were sacrificed between 25–27 weeks. The number of tumours, their localization, size and microscopic characteristics were recorded. A paired chi-squared analysis was performed comparing tumoral induction in the perianastomotic zone with the rest of colon with faeces. RESULTS: No tumours appeared in the dimethylhydrazine-free group. The percentage tumoral area was greater in the perianastomotic zone compared to tumours which had developed in the rest of colon with faeces (p = 0.014). CONCLUSION: We found a cocarcinogenic effect due to the creation of an anastomosis, when using an experimental model of colonic carcinogenesis induced by DMH in rats
Alpha-1 antitrypsin Pi*SZ genotype: Estimated prevalence and number of SZ subjects worldwide
The alpha-1 antitrypsin (AAT) haplotype Pi*S, when inherited along with the Pi*Z haplotype to form a Pi*SZ genotype, can be associated with pulmonary emphysema in regular smokers, and less frequently with liver disease, panniculitis, and systemic vasculitis in a small percentage of people, but this connection is less well established. Since the detection of cases can allow the application of preventive measures in patients and relatives with this congenital disorder, the objective of this study was to update the prevalence of the SZ genotype to achieve accurate estimates of the number of Pi*SZ subjects worldwide, based on studies performed according to the following criteria: 1) samples representative of the general population, 2) AAT phenotyping characterized by adequate methods, and 3) selection of studies with reliable results assessed with a coefficient of variation calculated from the sample size and 95% confidence intervals. Studies fulfilling these criteria were used to develop tables and maps with an inverse distance-weighted (IDW) interpolation method, to provide numerical and geographical information of the Pi*SZ distribution worldwide. A total of 262 cohorts from 71 countries were included in the analysis. With the data provided by these cohorts, a total of 1,490,816 Pi*SZ were estimated: 708,792 in Europe; 582,984 in America and Caribbean; 85,925 in Africa; 77,940 in Asia; and 35,176 in Australia and New Zealand. Remarkably, the IDW interpolation maps predicted the Pi*SZ prevalence throughout the entire world even in areas lacking real data. These results may be useful to plan strategies for future research, diagnosis, and management of affected individuals
A multi-country test of brief reappraisal interventions on emotions during the COVID-19 pandemic.
The COVID-19 pandemic has increased negative emotions and decreased positive emotions globally. Left unchecked, these emotional changes might have a wide array of adverse impacts. To reduce negative emotions and increase positive emotions, we tested the effectiveness of reappraisal, an emotion-regulation strategy that modifies how one thinks about a situation. Participants from 87 countries and regions (n = 21,644) were randomly assigned to one of two brief reappraisal interventions (reconstrual or repurposing) or one of two control conditions (active or passive). Results revealed that both reappraisal interventions (vesus both control conditions) consistently reduced negative emotions and increased positive emotions across different measures. Reconstrual and repurposing interventions had similar effects. Importantly, planned exploratory analyses indicated that reappraisal interventions did not reduce intentions to practice preventive health behaviours. The findings demonstrate the viability of creating scalable, low-cost interventions for use around the world
Alpha-1 antitrypsin Pi*Z gene frequency and Pi*ZZ genotype numbers worldwide: an update
In alpha-1 antitrypsin deficiency (AATD), the Z allele is present in 98% of cases with severe disease, and knowledge of the frequency of this allele is essential from a public health perspective. However, there is a remarkable lack of epidemiological data on AATD worldwide, and many of the data currently used are outdated. Therefore, the objective of this study was to update the knowledge of the frequency of the Z allele to achieve accurate estimates of the prevalence and number of Pi*ZZ genotypes worldwide based on studies performed according to the following criteria: 1) samples representative of the general population, 2) AAT phenotyping characterized by adequate methods, and 3) measurements performed using a coefficient of variation calculated from the sample size and 95% confidence intervals. Studies fulfilling these criteria were used to develop maps with an inverse distance weighted (IDW)-interpolation method, providing numerical and graphical information of Pi*Z distribution worldwide. A total of 224 cohorts from 65 countries were included in the study. With the data provided by these cohorts, a total of 253,404 Pi*ZZ were estimated worldwide: 119,594 in Europe, 91,490 in America and Caribbean, 3,824 in Africa, 32,154 in Asia, 4,126 in Australia, and 2,216 in New Zealand. In addition, the IDW-interpolation maps predicted Pi*Z frequencies throughout the world even in some areas that lack real data. In conclusion, the inclusion of new well-designed studies and the exclusion of the low-quality ones have significantly improved the reliability of results, which may be useful to plan strategies for future research and diagnosis and to rationalize the therapeutic resources available
Effect of ethanol consumption on colon cancer in an experimental model
Aims: the present study was designed to examine the effect of
an ethanol supplement on experimental colon carcinogenesis.
Material and methods: one hundred and ten 10-week-old
Sprague-Dawley rats were divided into five groups: group A (20
rats) received no treatment. Group B (20 rats) received a supple-
ment of ethanol at 1.23 g/kg of body weight per day added to
their drinking water for 24 weeks. Group C (30 rats) received 18
weekly doses of dimethylhydrazine (DMH) at 21 mg/kg of body
weight from the beginning of the study. Group D (20 rats) re-
ceived ethylen-diamin-tetracetic acid (EDTA) solution only for 18
weeks. Group E (20 rats) received ethanol at the same dose as
group B plus DMH injections at the same dose as the rats in
group C from the beginning of the study. All experimental ani-
mals were sacrified after 25-27 weeks.
Results: no significant differences in the number of rats that
developed tumors, number of tumor-free animals, and number of
tumors per rat, as well as in macro-microscopic tumoral findings
were observed for animals in group C compared to animals in
group E.
Conclusions: we concluded that the addition of an ethanol
supplement does not modify colorectal carcinogenesis using a dy-
namic model of tumor induction with DMH
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