Background: During hemorrhagic hypotension, sympathetic vasoconstriction crucially contributes to gut mucosal damage. Sympathetic blockade by thoracic epidural anesthesia has been shown to increase mucosal microvascular perfusion and to improve survival after severe hemorrhage in laboratory animals. This study investigates the effects of thoracic epidural anesthesia on intestinal microvascular perfusion during hemorrhagic hypotension in rats.
Methods: In 32 anesthetized Sprague-Dawley rats either lidocaine 2% (thoracic epidural anesthesia) or normal saline (control) was infused via thoracic epidural catheters. Hemorrhagic hypotension (mean arterial pressure 30 mmHg for 60 min) was induced by withdrawal of blood, which was subsequently retransfused for resuscitation. Functional capillary density and erythrocyte velocity in the mucosa and muscularis were determined by intravital microscopy. Leukocyte-endothelium interaction was studied in postcapillary venules and sympathetic nerve fibers of the intestinal wall were identified by immunohistochemistry.
Results: During hypotension functional capillary density was significantly (P < 0.001) lower in the muscularis of the control group (median [25/75 percentile]: -46.5% [-59.6/-20.8%] change from baseline) as compared with animals that received thoracic epidural anesthesia (-6.1% [-13.4/1.1%]). There were no differences in erythrocyte velocity between groups throughout the experiment. Leukocyte rolling increased significantly (P < 0.001) after resuscitation in control (12 [6/15]vs. baseline 2.5 [1/8]) but not in thoracic epidural anesthesia (4 [2.3/7]vs. baseline: 5 [3/15.5]). Sympathetic nerve fibers were identified in the muscularis and submucosa but not in the mucosa. 相似文献
The last decade witnessed major advances in the prevention and treatment of venous as well as of arterial thrombosis. Limitations of existing anticoagulants led to the development of novel therapeutic approaches. Ximelagatran is a new direct thrombin inhibitor (DTI) that is given orally, without the need for close monitoring. This compound was tried in the treatment of active venous thromboembolism, and the results were encouraging. Randomized trials suggest that ximelagatran is not inferior to warfarin in the prevention of stroke in patients with nonvalvular atrial fibrillation. Multiple controlled, prospective trials compared ximelagatran with low molecular weight heparin or warfarin in prevention of venous thromboembolism in patients undergoing major orthopedic procedures. The results of these clinical trials are reviewed in this article. Because of certain safety concerns (increased liver enzymes, potential hepatonecrosis, and increased coronary events) ximelagatran has not yet been approved by the FDA. Additional studies may be required to address these concerns. Ximelagatran has been approved, however, by the European regulatory authorities for short-term thromboprophylaxis. The success of ximelagatran or other oral antithrombin agents would provide significant proof of the concept for the long-term use of oral antithrombins in the prevention and treatment of both arterial and venous thrombosis. 相似文献
1.Control of inflammatory pain can result from activation of opioid receptors on peripheral sensory nerves by opioid peptides secreted from leukocytes in response to stress (e.g. experimental swim stress or surgery). The extravasation of immunocytes to injured tissues involves rolling, adhesion and transmigration through the vessel wall, orchestrated by various adhesion molecules. 2. Here we evaluate the relative contribution of selectins, integrins alpha(4) and beta(2), and platelet-endothelial cell adhesion molecule-1 (PECAM-1) to the opioid-mediated inhibition of inflammatory pain. 3. We use flow cytometry, double immunofluorescence and nociceptive (paw pressure) testing in rats with unilateral hind paw inflammation induced by complete Freund's adjuvant. 4. In inflamed tissue, 43-58% of hematopoietic cells (CD45(+)) expressed opioid peptides. L-selectin and beta(2) were coexpressed by 7 and 98% of opioid-containing leukocytes, respectively. Alpha(4) integrin was expressed in low levels by the majority of leukocytes. Opioid-containing cells, vascular P- and E-selectin and PECAM-1 were simultaneously upregulated. 5. Swim stress produced potent opioid-mediated antinociception in inflamed tissue, unaffected by blockade of PECAM-1. However, blockade of L- and P-selectins by fucoidin, or of alpha(4) and beta(2) by monoclonal antibodies completely abolished peripheral stress-induced antinociception. This coincided with a 40% decrease in the migration of opioid-containing leukocytes to inflamed tissue. 6. These findings establish selectins and integrins alpha(4) and beta(2), but not PECAM-1, as important molecules involved in stress-induced opioid-mediated antinociception in inflammation. They point to a cautious use of anti-inflammatory treatments applying anti-selectin, anti-alpha(4) and anti-beta(2) strategies because they may impair intrinsic pain inhibition. 相似文献
Introduction: Primary biliary cirrhosis (PBC) is a chronic autoimmune liver disease mostly seen in middle-aged women characterized by progressive nonsuppurative destruction of small bile ducts resulting in intrahepatic cholestasis, parenchymal injury and ultimately end-stage liver disease. Despite major breakthroughs in our understanding of PBC, there remains only one FDA-approved agent for treatment: ursodeoxycholic acid (UDCA) to which one-third of patients are unresponsive.
Areas covered: Biochemical response to treatment with UDCA is associated with excellent survival rates in PBC patients. However, there is a need for alternative treatments for nonresponders. Results from human epidemiological and genetic studies as well as preclinical studies in PBC animal models have provided a strong impetus for the development of new therapeutic agents. In this review, we discuss the recent advances in translational research in PBC focusing on promising therapeutic approaches, namely immune-based targeted therapies and agents targeting the synthesis and circulation of bile acids.
Expert opinion: We are in a new era for the development of novel therapies for PBC. Data on fibrates, budesonide and obeticholic acid offer encouragement for nonresponders to UDCA. 相似文献
Lead (Pb), a known environmental toxicant, adversely affects almost all organ systems. In this study, we investigated the effects of maternal lead exposure on fetal rat cerebellum. Female Sprague–Dawley rats were given lead nitrate in drinking water (0, 0.5, and 1%) for two weeks before conception, and during pregnancy. Fetuses were collected by caesarian section on gestational day 21 and observed for developmental abnormalities. The fetal cerebellar sections from control and 1% lead group were stained with cresyl violet. Immunohistochemical expressions of p53, Bax, Bcl-2, and caspase 3 were quantified by AnalySIS image analyzer (Life Science, Germany). Lead exposure induced developmental abnormalities of eyes, ear, limbs, neck and ventral abdominal wall; however, these abnormalities were commonly seen in the 1% lead-treated group. In addition, lead also caused fetal mortality and reduced body growth in both dose groups and reduced brain weight in the 1% lead-treated group. The fetal cerebella from the 1% lead-treated group showed unorganized cerebellar cortical layers, and degenerative changes in granule and Purkinje cells such as the formation of clumps of Nissl granules. An increase in Bax and caspase 3, and a decrease in Bcl-2 (p?0.05), but not in p53, showed apoptosis of the neurons. In conclusion, gestational lead exposure in rats induces fetal toxicity and developmental abnormalities. The lead exposure also impairs development of cerebellar layers, induces structural changes, and apoptosis in the fetal cerebellar cortex. These results suggest that lead exposure during gestation is extremely toxic to developing cerebellum in rats. 相似文献
Objective: This cross-sectional study assessed the effect of food donations on total nutrient intake of clients of a food pantry in Central Texas.
Methods: Nutrient intakes of total, base and food donation diets were estimated for 112 food pantry recipients using specific questionnaires; and then compared to the dietary reference intakes (DRI) and 2015–2020?US Dietary Guidelines.
Results: Food donations accounted for more than half of the client’s daily intake of energy, carbohydrates, vitamin B6, phosphorus, copper and selenium. Yet, daily total intake remained less than their DRIs for carbohydrates, poly-unsaturated fats, dietary fiber, fat soluble vitamins and vitamin C, and was even lower for calcium, magnesium and potassium. Total food intake of clients almost met the US Dietary Guidelines for refined grains, fruits, vegetables, and meat; however, the amount of whole grains and dairy was inadequate.
Conclusions: Supplemental foods offered at food pantries are an important resource for improving nutrient intake of low-income populations. 相似文献
Heparin as well as low-molecular-weight heparins (LMWHs) have polypharmacological actions at various levels. Earlier studies focused on the plasma anti-Xa and anti-IIa pharmacodynamics (PD) for the different LMWHs. Other important PD parameters for heparin and LMWHs might explain the diverse clinical impacts of this class of agents in thrombosis and beyond: the release of the vascular tissue factor pathway inhibitor (TFPI), inhibition of key matrix-degrading enzymes, and other mechanisms. There is much evidence for the key role of LMWHs in hypercoagulation in thrombosis and cancer, angiogenesis, and inflammatory disorders. Many cancer patients reportedly have a hypercoaguable state, with recurrent thrombosis due to the impact of cancer cells and chemotherapy or radiotherapy on the coagulation cascade. Studies have demonstrated that unfractionated heparin (UFH) or its low molecular weight fractions interfere with various processes involved in tumor growth and metastasis. Clinical trials have suggested a clinically relevant and improved efficacy of LMWHs, as compared to UFH, on the survival of cancer patients with deep vein thrombosis. Our laboratory has demonstrated a significant role for LMWHs and for LMWH-releasable TFPI on the regulation of angiogenesis, tumor growth, and tumor metastasis; we have also seen potent inhibition of matrix-degrading enzymes by LMWHs but not by TFPI. The antiangiogenesis effect of LMWHs or non-anticoagulant LMWH derivatives was shown to be reversed by anti-TFPI. Thus, modulation of tissue factor/VIIa noncoagulant activities by LMWH-releasable TFPI and the inhibitory effects on matrix-degrading enzymes beside the anticoagulant efficacy have provided an expanded clinical utility for LMWHs in angiogenesis-associated disorders, including human tumor growth and metastasis. 相似文献
Proximate, mineral, fatty acid and cholesterol composition of eight traditional sweets commonly consumed in the Arab Gulf countries were determined. Four sweets were obtained from Bahrain, whereas the other sweets were obtained from Oman. Protein level ranged from 0.2 to 9.0%, while the fat content ranged from 7.9 to 18.0%. In general, the sweets were found to be high in energy content but poor in most minerals. Iron and zinc contents were low (less than 2 and less than 1 mg/100 g for iron and zinc, respectively). Cholesterol was high in four sweets (range from 10.6 to 20.4 mg/100 g), mainly because of the use of animal fat in preparation of these sweets. The fatty acids profiles showed that palmitic and oleic acids were predominant. One sweet (eggbaith) was found to be very high in linoleic (42%) and low in palmitic (9.6%) acids. The study showed that some traditional sweets are nutritious, while others should be consumed with moderation. 相似文献
Nutritional supplements or complementary and alternative medicines (CAM) are currently being investigated for their use in preventing, inhibiting, and reversing the progression of cancer. Natural agents and their derivatives such as vitamin A, selenium, green tea, resveratrol, aspirin, and probiotics have potential benefits in chemoprevention. There is also growing evidence for the use of natural products as adjunctive therapy alongside conventional cancer treatments. Nutritional supplements expenditures demonstrated greater growth than pharmaceuticals, with approximately 80% of cancer patients using natural products. Current issues with nutritional supplements use in cancer treatment include insufficient or conflicting evidence, poor quality control, potential interactions with chemotherapy, and potential efficacy in relation to changes in certain biomarkers, but long-term implications remain largely unresolved. Continued research is needed to lend credibility to these potentially valuable naturally driven supplements in the prevention and potentially in the treatment of cancer in conjunction with standard pharmaceuticals. 相似文献