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911.
Immunotherapy is the only specific treatment for scorpion sting. In the present study, protective effects of polyvalent antivenom against hemodynamic disturbances, biomarkers (troponin T, creatinine kinase isoenzyme MB, Lactate dehydrogenase) changes, electrocardiogram abnormalities and histopathological complications in heart and lung induced by Mesobuthus eupeus scorpion venom was investigated in anesthetized rabbits. Twenty four rabbits were randomized into four equal groups: six rabbits in control group received 1 ml ultra-pure water subcutaneously (group 1). Group two received LD50 of venom (4.5 mg/kg). In the third and fourth groups, 5 ml of scorpion antivenom was administrated intravenously simultaneous with venom injection and 60 min following envenomation, respectively. Results of the present study indicate significant decrease in hemodynamic parameters following envenomation in the second group of animals. Venom injection caused edema, myocytolysis, coagulation necrosis, hemorrhage in heart as well as edema, hemorrhage and vascular thrombus in lungs. Although envenomed rabbits presented rises in LDH and TnT but no alteration in CK-MB was observed. Electrocardiogram monitoring of rabbits showed ST elevation and inverted T waves. Simultaneous administration of antivenom and venom prevented entirely the clinical signs, hemodynamic disturbances, markers changes, ECG abnormalities and histopathological damages. Delayed immunotherapy gradually ameliorated clinical signs, hemodynamic disturbances and markers changes related to envenomation. Histopathological evaluation showed slight alterations such as mild myocytolysis in heart and mild edema in lung following delayed immunotherapy. In conclusion, scorpion antivenom administration has preventive, neutralizing and curative properties for M. eupeus scorpion envenomation, if it would be applied at optimum time, dose and route.  相似文献   
912.
It is confirmed that pharmacological attenuation of glial cells can alleviate neuropathic pain by lowering proinflammatory cytokine expression. The present study tries to confirm that post-injury administration of glia inhibitor, minocycline, can attenuate the neuropathic pain symptoms and improves the efficacy of morphine anti-nociception in chronic constriction injury (CCI). Male Wistar rats (230-270 g) underwent surgery for induction CCI model of neuropathy. For assessment of the thermal hyperalgesia and mechanical allodynia after CCI induction, morphine (2.5, 5, 7.5, 10 and 15 mg/kg; s.c.) and saline were administered on post-operative days (PODs) 0, 6 and 14. Hargreaves and Von-Frey tests were performed before and 30 min after morphine administration, respectively. The results showed significant decrease in antinociceptive effect of morphine on POD 6 compared to POD 0 only at the dose of 5 mg/kg. On the other hand, on POD 14 the antinociceptive effect of morphine (5, 7.5, 10 and 15 mg/kg) significantly decreased in comparison with POD 0. In another set of experiments, animals received minocycline (10, 20 and 40 mg/kg; i.p.) for eight days from POD 6 to 13 and then the antinociceptive effect of single dose of morphine 5 mg/kg was tested on POD 14. Behavioral tests showed that minocycline (40 mg/kg) could effectively attenuate the thermal hyperalgesia and mechanical allodynia on POD 13. Moreover, minocycline (40, 20 mg/kg) improved the anti-hyperalgesic, and minocycline (40 mg/kg) improved the anti-allodynic effects of morphine 5 mg/kg on POD 14. It seems that the reduction of antinociceptive effect of morphine after CCI may be mediated through glia activation. Modulation of glial activity by minocycline can attenuate CCI-induced neuropathic pain. It is also shown that repeated post-injury administration of minocycline improves the antinociceptive effect of morphine in neuropathic pain.  相似文献   
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916.

Introduction

Circulating lipopolysaccharides released from bacteria may activate both neutrophils and monocytes. The activated neutrophils release myeloperoxidase (MPO), a specific enzyme with strong oxidative activity. The aim of this study was to evaluate MPO enzyme activity in plasma of critically ill patients and to check the hypothesis that these concentrations in plasma would be higher in sepsis and systemic inflammatory conditions, as neutrophils release their contents before proliferating in response to stress.

Material and Methods

Blood samples were collected from 105 critically ill patients admitted to the intensive care unit, consisting of those with systemic inflammatory response syndrome (n = 42), sepsis (n = 37), and septic shock (n = 26). Plasma MPO enzyme activity was determined by o-dianisidine-H2O2 method, modified for 96-well plates.

Results

The plasma MPO enzyme activity in sepsis patients was significantly higher than that in the control group (mean, 2.4 ± 1.8 in sepsis and 1.86 ± 1.2 nmol per milligram protein per 10 minutes in systemic inflammatory response syndrome vs 0.32 ± 0.11 nmol per milligram protein per 10 minutes in healthy controls). Mean plasma lactate levels in sepsis (7.8 ± 1.2 mmol/L) and shock patients (9.5 ± 1.2 mmol/L) and cytokines like tumor necrosis factor–α, interleukin-8, and interleukin-1β were simultaneously evaluated to establish onset of inflammation and sepsis. These results show that neutrophil activation occurring during inflammation and sepsis could be detected by plasma MPO concentration.

Conclusion

The plasma MPO concentrations may be a marker of the neutrophil proliferation and severity of inflammation.  相似文献   
917.
Hörnblad A  Cheddad A  Ahlgren U 《Islets》2011,3(4):204-208
Optical projection tomography (OPT) imaging is a powerful tool for three-dimensional imaging of gene and protein distribution patterns in biomedical specimens. We have previously demonstrated the possibility, by this technique, to extract information of the spatial and quantitative distribution of the islets of Langerhans in the intact mouse pancreas. In order to further increase the sensitivity of OPT imaging for this type of assessment, we have developed a protocol implementing a computational statistical approach: contrast limited adaptive histogram equalization (CLAHE). We demonstrate that this protocol significantly increases the sensitivity of OPT imaging for islet detection, helps preserve islet morphology and diminish subjectivity in thresholding for tomographic reconstruction. When applied to studies of the pancreas from healthy C57BL/6 mice, our data reveal that, at least in this strain, the pancreas harbors substantially more islets than has previously been reported. Further, we provide evidence that the gastric, duodenal and splenic lobes of the pancreas display dramatic differences in total and relative islet and β-cell mass distribution. This includes a 75% higher islet density in the gastric lobe as compared to the splenic lobe and a higher relative volume of insulin producing cells in the duodenal lobe as compared to the other lobes. Altogether, our data show that CLAHE substantially improves OPT based assessments of the islets of Langerhans and that lobular origin must be taken into careful consideration in quantitative and spatial assessments of the pancreas.  相似文献   
918.
Ramadan, the ninth month of Islamic lunar calendar, is marked by religious ritual of fasting from early dawn till sunset by Muslims. Islam has allowed many categories of people to be exempt totally or temporarily from fasting. Patients with uncontrolled diabetes face possible major metabolic risks including hypoglycemia, hyperglycemia with or without the risk of impending ketosis, dehydration, and thrombosis. Diabetics can be stratified into four categories based on their level of risk associated with fasting. The recommended ruling for persons in categories 1 and 2 is that they are prohibited from fasting to prevent harming themselves based on the certainty or the preponderance of probability that harm will occur, whereas the recommended ruling for those in categories 3 and 4 is that they should fast. The strategies to ensure safety of diabetics who are planning to fast include Ramadan-focused patient education, pre-Ramadan medical assessment, following a healthy diet and physical activity pattern, physician-recommended modifications in medication protocol and therapeutic recommendations and checking blood glucose as and when required.  相似文献   
919.
Background: Peripheral arterial disease (PAD) has been described as a rising epidemic in recent years. The majority of subjects studied in PAD literature have been male, leaving female patients an underrepresented population with regard to revascularization outcomes. The goal of our study was to determine the death rate and predictors of mortality in female patients undergoing endovascular intervention (EI) for symptomatic PAD. Methods and Results: This study was conducted as a single‐center retrospective chart review of 292 female patients who underwent EI for symptomatic PAD. Patient variables including demographics and procedural data were analyzed for statistical significance with regard to mortality. Age, history of congestive heart failure (CHF), and chronic kidney disease (CKD) were found to be significant predictors of mortality on multivariable analysis. A death risk score was formulated based on the above variables, risk stratifying patients into low, medium, or high risk groups for mortality after EI. Overall, 76 patients (26%) fell into the low risk category with a mortality of 5.3%, 102 patients (35%) fell into the moderate risk with a mortality of 15.7%, and 112 patients (39%) fell into the high‐risk group with a mortality of 45.5% (P < 0.0001). Conclusions: Our study is the first of its kind to specify predictors of mortality in female patients with symptomatic PAD. This study also provides a tool to identify female PAD patients at high risk for death after EI. Finally, it highlights the effect of CKD, age, and CHF on mortality of patients with PAD. (J Interven Cardiol 2011;24:555–561)  相似文献   
920.
The prevalence of type 2 diabetes continues to increase at an alarming rate around the world, with even more people being affected by prediabetes. Although the pathogenesis and long-term complications of type 2 diabetes are fairly well known, its treatment has remained challenging, with only half of the patients achieving the recommended hemoglobin A1c target. This narrative review explores the pathogenetic rationale for the treatment of type 2 diabetes, with the view of fostering better understanding of the evolving treatment modalities. The diagnostic criteria including the role of hemoglobin A1c in the diagnosis of diabetes are discussed. Due attention is given to the different therapeutic maneuvers and their utility in the management of the diabetic patient. The evidence supporting the role of exercise, medical nutrition therapy, glucose monitoring, and antiobesity measures including pharmacotherapy and bariatric surgery is discussed. The controversial subject of optimum glycemic control in hospitalized and ambulatory patients is discussed in detail. An update of the available pharmacologic options for the management of type 2 diabetes is provided with particular emphasis on newer and emerging modalities. Special attention has been given to the initiation of insulin therapy in patients with type 2 diabetes, with explanation of the pathophysiologic basis for insulin therapy in the ambulatory diabetic patient. A review of the evidence supporting the efficacy of the different preventive measures is also provided.  相似文献   
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