29 research outputs found

    Placental CD4(+) T cells from preeclamptic patients cause autoantibodies to the angiotensin II type I receptor and hypertension in a pregnant rat model of preeclampsia

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    AIM: Preeclampsia (PE) is a hypertensive disorder of pregnancy associated with activated CD4(+) T cells and autoantibodies to angiotensin II type 1 receptor (AT1-AA). We have previously shown that CD4(+) T cells isolated from women with PE cause hypertension, increased tumor necrosis factor alpha (TNF-Îą), endothelin-1, and soluble fms-like tyrosine kinase-1 (sFlt-1) when injected into pregnant nude-athymic rats compared to CD4(+) T cells from normal pregnant (NP) women. However, the role of PE CD4(+) T cells to cause AT1-AA as a mechanism of hypertension is not known. Our goal was to determine if PE CD4(+) T cells stimulate AT1-AA in pregnant nude-athymic rats. METHODS: CD4(+) T cells were isolated from human NP and PE placentasand injected into nude-athymic rats on gestational day (GD) 12. In order to examine the role of the PE CD4(+) T cells to stimulate B cell secretion of AT1-AA, a subset of the rats receiving PE CD4(+) T cells were treated with rituximab on GD 14 or anti-CD40 ligand (anti-CD40L) on GD 12. On GD 19, mean arterial pressure (MAP) and tissues were obtained. RESULTS: MAP [114 Âą 1 mmHg (n = 9)] and AT1-AA [19.8 Âą 0.9 beats per minute (bpm, n = 4)] were increased in NP nude + PE CD4(+) T cells compared to NP nude + NP CD4(+) T cells [98 Âą 2 mmHg (n = 7, P < 0.05) and 1.3 Âą 0.9 bpm (n = 5, P < 0.05)]. Rituximab (103 Âą 2 mmHg, n = 3, P < 0.05) and anti-CD40L (102 Âą 1 mmHg, n = 3, P < 0.05) lowered MAP compared to NP nude + PE CD4(+) T cells. Circulating a proliferation-inducing ligand (APRIL) and placental angiotensin-converting enzyme 2 (ACE-2) activity was increased in response to PE CD4(+) T cells. CONCLUSIONS: These results show that placental CD4(+) T cells play an important role in the pathophysiology of PE, by activating B cells secreting AT1-AA to cause hypertension during pregnancy

    An Electrode Array for Limiting Blood Loss During Liver Resection: Optimization via Mathematical Modeling

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    Liver resection is the current standard treatment for patients with both primary and metastatic liver cancer. The principal causes of morbidity and mortality after liver resection are related to blood loss (typically between 0.5 and 1 L), especially in cases where transfusion is required. Blood transfusions have been correlated with decreased long-term survival, increased risk of perioperative mortality and complications. The goal of this study was to evaluate different designs of a radiofrequency (RF) electrode array for use during liver resection. The purpose of this electrode array is to coagulate a slice of tissue including large vessels before resecting along that plane, thereby significantly reducing blood loss. Finite Element Method models were created to evaluate monopolar and bipolar power application, needle and blade shaped electrodes, as well as different electrode distances. Electric current density, temperature distribution, and coagulation zone sizes were measured. The best performance was achieved with a design of blade shaped electrodes (5 × 0.1 mm cross section) spaced 1.5 cm apart. The electrodes have power applied in bipolar mode to two adjacent electrodes, then switched sequentially in short intervals between electrode pairs to rapidly heat the tissue slice. This device produces a ~1.5 cm wide coagulation zone, with temperatures over 97 ºC throughout the tissue slice within 3 min, and may facilitate coagulation of large vessels

    Track D Social Science, Human Rights and Political Science

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    Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/138414/1/jia218442.pd

    Fontes de carboidratos e ionóforo em dietas contendo óleo vegetal para ovinos: digestibilidade, balanço de nitrogênio e fluxo portal de nutrientes Carbohydrate sources and ionophore in sheep diets with vegetal oil: digestibility, nitrogen balance and portal flux of nutrients

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    Os objetivos neste trabalho foram avaliar a utilização de duas fontes de carboidratos (casca de soja e milho), com a utilização ou não de monensina em dietas com alta densidade lipídica, e seus efeitos sobre a digestibilidade dos nutrientes, o balanço de nitrogênio e o fluxo portal de nutrientes em ovinos. Adotou-se o mÊtodo de coleta total de fezes e urina para determinação da digestibilidade e do balanço de nitrogênio. O fluxo líquido de nutrientes foi calculado pelo princípio de Fick. Foram utilizados quatro ovinos (54 kg de PV) da raça Corriedale com três cateteres implantados (veia e artÊria mesentÊrica e veia porta). A ingestão, a excreção fecal, a digestão e a digestibilidade de MS, MO e EE não foram influenciadas pelos tratamentos. A ingestão, a digestão e a digestibilidade da FDN foram maiores para as dietas com casca de soja (757,0; 531,1 g/dia e 70,2%) que para aquelas com milho (392,3; 199,9 g/dia e 51,0%), enquanto a dos carboidratos não-fibrosos (CNF), foram maiores para as dietas com milho (474,6, 416,8 g/dia e 87,8%) que para aquelas com casca de soja (148,0; 97,8 g/dia e 66,1%). A concentração de energia expressa como NDT foi maior nas dietas com milho (80,2%) que naquelas com casca de soja (76,7%). Não houve efeito da utilização da monensina nos parâmetros de digestibilidade e balanço de nitrogênio. A excreção fecal da proteína foi menor e a digestibilidade maior para as dietas com milho. A concentração portal e arterial de nitrogênio alfa amino (N alfa-amino) foi menor para as dietas com monensina (3,161 e 2,922 e 3,530 e 3,218 mM, respectivamente). A concentração portal (0,419 vs 0,516 mM), a diferença venosa-arterial (0,230 vs 0,317 mM) e o fluxo portal de amônia (26,119 vs 37,041 mM/h) foram menores para as dietas com milho.<br>The objectives of this trial were to evaluate the effects of two carbohydrate sources (soybean hulls and corn grain) with and without monensin on digestibility, nitrogen balance and portal nutrient flux in sheep fed high vegetable oil diets. Four Corriedale wethers averaging 54 kg of body weight and fitted with catheters in the mesenteric and portal veins and also in the mesenteric artery were used. Digestibility and nitrogen balance were determined using total collection of feces and urine. Net nutrient flux was calculated using the Fick principle. Intake, fecal excretion, digestion and digestibility of dry matter (DM), organic matter (OM) and ether extract (EE) were not affected by treatments. However, intake, digestion and digestibility of neutral detergent fiber (NDF) were higher when animals were fed soybean hulls (757.0 g/d, 531.1 g/d and 70.2%) rather than corn grain (392.3, 199.9 g/d and 51.0%). Conversely, intake, digestion and digestibility of nonfiber carbohydrates (NFC) as well as TDN content were greater on corn (474.6 g/d, 416.8 g/d, 87.8%, 80.2%) than on soybean hulls diets (148.0 g/d, 97.8 g/d and 66.1%, 76.7%). There was no effect of monensin on nutrient digestibility and nitrogen balance. Fecal excretion of protein was lower and protein digestibility was higher for corn diets. Alpha-amino-nitrogen concentration in arterial and portal plasma was lower for diets supplemented with monensin (3.161 and 2.922 mM) compared to non-supplemented monsesin diets (3.530 and 3.218 mM), respectively. Portal concentration (0.419 vs. 0.516 mM), venous-arterial difference (0.230 vs. 0.317 mM), and portal flux (26.119 vs. 37.041 mM/h) of ammonia were all lower on corn diets
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