R56865, a Na- and Ca-Overload Inhibitor, Reduces Myocardial Ischemia-Reperfusion Injury in Blood-Perfused Rabbit Hearts

The cardioprotective effects of R56865 were studied in isolated rabbit hearts, blood-perfused with a support rabbit system. The effect on ischemic injury was evaluated by comparing myocardial contracture and contents of ATP catabolites and of lactate during 60 min of normothermic ischemia in untreated hearts (group I) and in hearts treated with 0.63 mg/kg of R56865 starting 20 min before ischemia (group II; n = 5 in each group). R56865 delayed the onset, and decreased the extent of ischemic contracture, but had no effect on the myocardial content of ATP, of its catabolites or of lactate. The effect on reperfusion injury was studied by monitoring left ventricular function during 80-min reperfusion after the 60-min ischemia in three groups (n = 6 in each): an untreated group (group I) and two groups treated with R56865 given either before (group II) or after ischemia (group III). Ultrastructural changes and cellular calcium distribution after reperfusion were also studied. R56865 improved the recovery of function and prevented contracture during reperfusion. Left ventricular end-diastolic pressure was 13.2 ± 2.8 mmHg in group II and 31.3 ± 8.1 mmHg in group III vs 45.0 ± 2.6 mmHg in group I (P < 0.0001 for II vs I; P > 0.05 for III vs I). Left ventricular developed pressure, maximum dP/dt and minimum dP/dt recovered to 71.0 ± 5.4%, 98.9 ± 6.1%, 85.3 ± 4.8% of baseline values, respectively, in group II, to 64.5 ± 3.0% (P > 0.05), 76.8 ± 3.0%, 70.2 ± 4.0% in group III, vs 52.0 ± 6.5%, 58.9 ± 6.9% and 53.6 ± 5.8% in untreated hearts (P < 0.05 for II or III vs I). Coronary flow was 24.5 ± 2.2 ml/min and 19.8 ± 1.8 ml/min in groups II and III vs 14.8 ± 0.7 ml/min (P < 0.05) in the untreated group. On histology the myocardium in hearts treated either before after ischemia was well protected and calcium distribution was almost normal after reperfusion, while in untreated hearts, most of the myocardium displayed irreversible damage accompanied by massive intracellular calcium accumulation. We conclude that R56865 could attenuate Ca²⁺-overload, thereby reducing myocardial ischemia-reperfusion injury after an extended period of ischemia.     

Acinar cell carcinoma of the pancreas: is the absence of neuroendocrine component related to a more malignant behavior?

BACKGROUND/AIMS: Acinar cell carcinomas are uncommon malignant tumors of the pancreas, accounting for 1-2% of all the cases of exocrine pancreatic tumor. Some authors have estimated acinar cell tumors to be as aggressive as ductal adenocarcinoma of the pancreas whereas other series showed acinar cell tumors to have a favorable clinical outcome. This discrepancy in prognosis may be related to the cellular components of the tumor. METHODOLOGY: With the aim to evaluate the possible relationship between the presence of neuroendocrine differentiation and behavior of these tumors, the authors reviewed all patients presenting acinar cell carcinoma of the pancreas in the last 5 years with emphasis in the immunohistochemical evaluation. RESULTS: Four patients presented neuroendocrine differentiation on immunohistochemical evaluation and had a more benign outcome. Two patients without neuroendocrine component had a disseminated disease at presentation. This data suggests that this tumor is less aggressive than ductal adenocarcinoma and even with nodal involvement, long-term survival after complete resection can be achieved. CONCLUSIONS: It is possible that the absence of neuroendocrine component may be related to a less favorable outcome and adjuvant therapy may be necessary. Due to the rarity of this pancreatic tumor, this relationship remains to be confirmed with a multicentric study including a larger number of patients.     

Protective effects of silymarin on epirubicin-induced mucosal barrier injury of the gastrointestinal tract

Mucositis is a serious disorder of the gastrointestinal tract that results from cancer chemotherapy. We investigated the protective effects of silymarin on epirubicin-induced mucosal barrier injury in CD-1 mice. Immunohistochemical activity of both pro-apoptotic Bax and anti-apoptotic Bcl-2 markers, together with p53, cyt-P450 expression and DNA damage analysis on stomach, small intestine and colon were evaluated. Our results indicated stronger expression for cyt P450 in all analyzed gastrointestinal tissues of Epi group, which demonstrate intense drug detoxification. Bax immunopositivity was intense in the absorptive enterocytes and lamina connective cells of the small intestine, surface epithelial cells of the stomach and also in the colonic epithelium and lamina concomitant with a decreased Bcl-2 expression in all analyzed tissues. Epirubicin-induced gastrointestinal damage was verified by a goblet cell count and morphology analysis on histopathological sections stained for mucins. In all analyzed tissues, Bax immunopositivity has been withdrawn by highest dose of silymarin concomitant with reversal of Bcl-2 intensity at a level comparable with control. p53 expression was found in all analyzed tissues and decreased by high dose of silymarin. Also, DNA internucleosomal fragmentation was observed in the Epi groups for all analyzed tissues was almost suppressed at 100?mg/kg Sy co-treatment. Histological aspect and goblet cell count were restored at a highest dose of Sy for both small and large intestine. In conclusion, our findings suggest that silymarin may prevent cellular damage of epirubicin-induced toxicity and was effective in reducing the severity indicators of gastrointestinal mucositis in mice.     

Enrollment in Hispanic Serving Institutions as a Moderator of the Relationship Between Drinking Norms and Quantity of Alcohol Use Among Hispanic College Students

Background: Hispanic college students represent a growing proportion of the college population. Studies have found that an individual's perception of the drinking of others is linked to one's own personal use and that college students frequently overestimate the drinking of their peers. The current study builds on previous college student drinking literature by examining the influence that attending a Hispanic-serving institution (HSI) has on the personal alcohol use and perception of peers’ drinking norms among Hispanic college students. Methods: This secondary data analysis utilized data from the American College Health Association's National College Health Assessment. Participants were self-identified Hispanics between the ages of 18 and 25 (N = 4336). Results: Results indicated that there was a significant interaction between attending an HSI and the perception of the number of drinks of a typical student. Specifically, the perception of others’ drinking was more strongly linked to personal drinking for students in non-Hispanic serving institutions. Conclusions: The protective effect of attending a Hispanic-serving institution may be related to a more culturally affirming college environment.     

Challenges and prospects in the public health research system in the occupied Palestinian territory: a qualitative study

Background

A public health research system is the bedrock of health systems to improve population health, system responsiveness, and equity. An international concern, referred to as the 10/90 gap, is that less than 10% of global funds are devoted to diseases or conditions that account for 90% of the global disease burden, particularly in developing countries. Palestinian health research is progressing, but it is not sufficiently investigated, with a remarkable knowledge gap on its conceptualisation, stewardship, stakeholders, and capacity and resources. The aim of this study was to understand the Palestinian public health research system by investigating challenges related to the system components that need to be strengthened.