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1.
Fifty-one children under the age of 10 years admitted to a general hospital in Trinidad had a confirmed diagnosis of malrotation of the intestines. This was the primary diagnosis in 20 cases. Analysis of the records of these 20 revealed that one-half were less than 1 month of age at first presentation. Vomiting was a universal complaint, and nearly two-thirds were malnourished. Disturbed bowel habit, anorexia and abdominal pain were also reported. In 30% (six of 20) there were signs of dehydration; an equal number had features of intestinal obstruction. Radiological investigation provided the diagnosis in all but one child, who underwent surgical exploration with a provisional diagnosis of appendicitis. Although a volvulus was found in 35% of cases, no resections were necessary. A high rate of morbidity and a mortality rate of 15% highlight the problems involved in the surgical care of young infants.  相似文献   
2.
Recent studies have shown that the hand-pointing movements within arm's reach remain invariant whether the trunk is recruited or not or its motion is unexpectedly prevented. This suggests the presence of compensatory arm-trunk coordination minimizing the deflections of the hand from the intended trajectory. It has been postulated that vestibular signals elicited by the trunk motion and transmitted to the arm motor system play a major role in the compensation. One prediction of this hypothesis is that vestibular stimulation should influence arm posture and movement during reaching. It has been demonstrated that galvanic vestibular stimulation (GVS) can influence the direction of pointing movements when body motion is restrained. In the present study, we analyzed the effects of GVS on trunk-assisted pointing movements. Subjects either moved the hand to a target or maintained a steady-state posture near the target, while moving the trunk forward with the eyes closed. When GVS was applied, the final position of the hand was deviated in the lateral and sagittal direction in both tasks. This was the result of two independent effects: a deviation of the trunk trajectory and a modification of the arm position relative to the trunk. Thus, the vestibular system might be directly involved not only in the control of trunk motion but also in the arm-trunk coordination during trunk-assisted reaching movements. Electronic Publication  相似文献   
3.
Subnormal levels of HDL cholesterol constitute a major cardiovascular risk factor. Inhibitors of cholesteryl ester transfer protein (CETP) are presently the most potent HDL-raising agents. Torcetrapib was the first CETP inhibitor to enter a large-scale, prospective, placebo-controlled interventional trial, which was prematurely terminated in December 2006 because of excess cardiovascular and noncardiovascular mortality in the active treatment group. Therapy with torcetrapib was associated with considerable increases in aldosterone level and blood pressure and changes in serum electrolytes indicative of mineralocorticoid excess. These findings indicate that torcetrapib has off-target toxic effects unrelated to HDL raising that involve the activation of mineralocorticoid receptors by aldosterone and result in the induction of hypertension. In contrast with torcetrapib, other CETP inhibitors such as JTT-705 and MK-825 do not increase blood pressure in humans, an observation which discounts a class effect. The available data do not, however, exclude potential adverse effects of CETP inhibition such as the generation of HDL particles that have deficient biological activities and a deleterious impact on reverse cholesterol transport and steroid metabolism. Normalization of both defective HDL function and diminished HDL levels should, therefore, be the focus of pharmacological HDL raising in future studies.  相似文献   
4.
OBJECTIVE: With the present studies we sought to determine how treatment with nitroglycerin (NTG) affects endothelial function, oxidative stress and nitric oxide (NO)-downstream signaling in Watanabe heritable hyperlipidemic rabbits (WHHL). BACKGROUND: In vitro experiments have demonstrated potent antiatherosclerotic effects of NO suggesting that treatment with NO-donors such as NTG could compensate for the diminished availability of endothelial NO. Nitric oxide may, however, not only be scavenged by reaction with endothelium-derived superoxide but also form the potent oxidant and inhibitor of vascular function, peroxynitrite (ONOO(-)). METHODS: Watanabe heritable hyperlipidemic rabbits were treated for three days with NTG patches. Normolipidemic New Zealand White rabbits (NZWR) served as controls. Endothelial function was assessed ex vivo with organ chamber experiments and vascular superoxide was quantified using lucigenin (5 and 250 microM) and CLA-enhanced chemiluminescence. Vascular ONOO(-) formation was determined using nitrotyrosine antibodies. The activity of the cGMP-dependent kinase (cGK-I) was assessed by determining the phosphorylation of vasodilator-stimulated phosphoprotein VASP (P-VASP). RESULTS: Nitroglycerin treatment caused endothelial dysfunction in NZWR and WHHL, associated with an increase in superoxide and ONOO(-) production and a substantial drop in cGK-I activity. In vivo NTG-treatment decreased lipophilic antioxidants (alpha- and beta-carotene) in NZWR and WHHL. Treatment of NZWR with NTG also decreased plasma extracellular superoxide dismutase (EC-SOD)-activity. CONCLUSIONS: Nitroglycerin treatment of WHHL with exogenous NO worsens rather than improves endothelial dysfunction secondary to increased formation of superoxide and/or peroxynitrite leading to decreased cGK-I activity. The decrease in plasma levels of alpha- and beta-carotene may be at least in part due to a decrease in EC-SOD activity.  相似文献   
5.
AIM: To explain the role of Monocyte chemotactic protein-1 (MCP-1) and soluble adhesion molecules in chronic hepatitis C during the treatment of interferon alpha (IFNα) 2 b and ribavirin (RBV).METHODS: Concentrations of MCP-1, soluble adhesion molecules intercellular adhesion molecule-1 (sICAM-1), sPselectin, interleukin (IL) 6, and ILl0 in serum were estimated in the group of 40 patients with chronic hepatitis C treated with IFNalpha2 b and RBV in 0, 16, 32, 48 wk of the therapy.RESULTS: In chronic hepatitis C, before and during the treatment, the serum levels of MCP-1 and sP-selectin in responders were similar to those of healthy subjects. In nonresponders (NR), MCP-1 increased in the course of IFN(α+RBV treatment, differences were statistically significant as compared to responders. MCP-1 correlated statistically with the activity of periportal inflammation (r= 0.35, P<0.05) but not with staging of liver fibrosis, sICAM-1 positively correlated with inflammatory activity and fibrosis in NR. sP-selectin did not correlate with histological findings in the liver. The MCP-1 correlated with the soluble form of sP-selectin concentrations (r= 6, P<0.001) and with IL-10 level in NR (r = 0.4, P<0.05). There was no correlation observed between the concentration of MCP-1 and sICAM-1, IL-6 during the treatment.CONCLUSION: MCP-1 concentration may be a prognostic marker of the efficacy of IFN+RBV therapy in patients with chronic hepatitis C.  相似文献   
6.
The immune system, its cellular and humoral response, is engaged by the host organism to fight against parasitic invasions. The group examined consisted of 38 women aged 19-39 years infected with Toxoplasma gondii. The diagnosis was established basing on serologic examination. Blood for analysis was collected before antiparasitic treatment. Control group consisted of 40 healthy women aged 18-46 years. The concentrations of IgM, IgG and IgE were assayed using a set of VIDAS (bioMerieux) according to the ELFA method. The concentrations of IL-5, IL-6 were assayed using a set of Quantikine human (R&D Systems) according to the immunoenzymatic methods with labeled antibodies. The present study revealed that in toxoplasmosis the concentration of IgE, IL-5 and IL-6 contents in blood serum was 2-times higher, than in healthy controls.  相似文献   
7.
8.
AIM: To assess the sICAM-1, sVCAM-1, and sP-selectin levels in children with Helicobacter pylori (H pylori) infection and to evaluate their significance for the morphological changes found in gastric mucosa. METHODS: The study included 106 children: 59 children (55.7%) with chronic gastritis and positive IgG against H pylori, 29 children (27.3%) after previous H pylori infection without the bacterium colonization but with positive IgG against H pylori, and 18 children (17%) with functional disorders of the gastrointestinal system but with normal IgG against H pylori. Endoscopic and histopathological evaluation of gastric mucosa was performed based on the Sydney System classification. The evaluation of sP-selectin, sICAM-1, sVCAM-1 levels in the sera of children was carried out using ELISA test. RESULTS: The assessment of gastritis activity degrees indicated statistically significant values in the antrum and corpus (P<0.001) of children examined. Serum sVCAM-1 levels were higher in group with gastritis due to H pylori infection than in group without infection and differed statistically (P<0.05). Serum sVCAM-1 levels proved to be the highest among other adhesive molecules in infected children and decreased after eradication of H pylori. Serum sICAM-1 levels were similar in all examined groups. Serum sP-selectin levels were similar in children with and without H pylori infection. CONCLUSION: Assessment of adhesive molecules (sP-selectin, sICAM-1, sVCAM-1) in the sera of children with active H pylori infection can show the participation of sVCAM-1 in the pathogenesis of gastric mucosal inflammation. sP-selectin and sICAM-1 concentrations in the sera of children with H pylori infection after eradication cannot reveal any significant differences as compared to healthy children.  相似文献   
9.
PURPOSE: The purpose of this study was to characterize the activity of the Bcl-2 protein family inhibitor ABT-263 in a panel of small cell lung cancer (SCLC) xenograft models. EXPERIMENTAL DESIGN: A panel of 11 SCLC xenograft models was established to evaluate the efficacy of ABT-263. Single agent activity was examined on a continuous dosing schedule in each of these models. The H146 model was used to further evaluate dose and schedule, comparison to standard cytotoxic agents, and induction of apoptosis. RESULTS: ABT-263 exhibited a range of antitumor activity, leading to complete tumor regression in several models. Significant regressions of tumors as large as 1 cc were also observed. The efficacy of ABT-263 was also quite durable; in several cases, minimal tumor regrowth was noted several weeks after the cessation of treatment. Antitumor effects were equal or superior to that of several clinically approved cytotoxic agents. Regression of large established tumors was observed through several cycles of therapy and efficacy was retained in a Pgp-1 overexpressing line. Significant efficacy was observed on several dose and therapeutic schedules and was associated with significant induction of apoptosis. CONCLUSIONS: ABT-263 is a potent, orally bioavailable inhibitor of Bcl-2 family proteins that has recently entered clinical trials. The efficacy data reported here suggest that SCLC is a promising area of clinical investigation with this agent.  相似文献   
10.
Akt is a serine/threonine kinase that transduces survival signals from survival/growth factors. Deregulation and signal imbalance in cancer cells make them prone to apoptosis. Upregulation or activation of Akt to aid the survival of cancer cells is a common theme in human malignancies. We have developed small-molecule Akt inhibitors that are potent and specific. These Akt inhibitors can inhibit Akt activity and block phosphorylation by Akt on multiple downstream targets in cells. Synergy in apoptosis induction was observed when Akt inhibitors were combined with doxorubicin or camptothecin. Akt inhibitor-induced enhancement of topoisomerase inhibitor cytotoxicity was also evident in long-term cell survival assay. Synergy with paclitaxel in apoptosis induction was evident in cells pretreated with paclitaxel, and enhancement of tumor delay by paclitaxel was demonstrated through cotreatment with Akt inhibitor Compound A (A-443654). Combination with other classes of chemotherapeutic agents did not yield any enhancement of cytotoxicity. These findings provide important guidance in selecting appropriate classes of chemotherapeutic agents for combination with Akt inhibitors in cancer treatment.  相似文献   
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