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ObjectiveTo evaluate the wound healing effect of aqueous extract of Crotalaria verrucosa (C. verrucosa) in rats.MethodsThree wound models including incision, excision and dead space wounds were used in this study. The parameters studied were breaking strength in incision models, granulation tissue dry weight, breaking strength and hydroxyproline content in dead space wounds, percentage of wound contraction and period of epithelialization in excision wound model.ResultsTwo doses of the extract with and without dexamethasone showed significant increases in mean hydroxyproline, total protein content and dry weight of granulation tissue but it was higher with dose 800 mg/kg comparing with the control. The dexamethasone treated group showed a significant (P<0.001) reduction in the wound breaking strength when compared to control group in incision type of wound model. Coadministration of C. verrucosa with dexamethasone significantly (P<0.001) increased the breaking strength compared to the dexamethasone treated only group. In excision wound model, the percentage of the wound contraction was significantly (P<0.01) increased by two doses of test extract on all the days except the lower dose which exhibited only on 12 th, 16 th days of drug treatment and it also reversed the dexamethasone suppressed wound contraction. It significantly (P <0.001) reduced the time required for epithelialization and reversed the epithelialization delaying effect of dexamethasone (P<0.001).ConclusionsC. verrucosa was found to possess significant wound healing property. This was evident by decrease in the period of epithelialization, increase in the rate of wound contraction, skin breaking strength, and granulation tissue dry weight content. Hence C. verrucosa could be a good wound healing agent.  相似文献   
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Bhatia  R; McGlave  PB; Dewald  GW; Blazar  BR; Verfaillie  CM 《Blood》1995,85(12):3636-3645
The bone marrow microenvironment supports and regulates the proliferation and differentiation of hematopoietic cells. Dysregulated hematopoiesis in chronic myelogenous leukemia (CML) is caused, at least in part, by abnormalities in CML hematopoietic progenitors leading to altered interactions with the marrow microenvironment. The role of the microenvironment itself in CML has not been well characterized. We examined the capacity of CML stroma to support the growth of long-term culture-initiating cells (LTC-IC) obtained from normal and CML marrow. The growth of normal LTC-IC on CML stroma was significantly reduced compared with normal stroma. This did not appear to be related to abnormal production of soluble factors by CML stroma because normal LTC- IC grew equally well in Transwells above CML stroma as in Transwells above normal stroma. In addition, CML and normal stromal supernatants contained similar quantities of both growth-stimulatory (granulocyte colony-stimulating factor (CSF), interleukin-6, stem cell factor, granulocyte-macrophage CSF, and interleukin-1 beta) and growth- inhibitory cytokines (transforming growth factor-beta, macrophage inflammatory protein-1 alpha, and tumor necrosis factor-alpha). The relative proportion of different cell types in CML and normal stroma was similar. However, polymerase chain reaction and fluorescence in situ hybridization studies showed the presence of bcr-abl-positivo cells in CML stroma, which were CD14+ stromal macrophages. To assess the effect of these malignant macrophages on stromal function, CML and normal stromal cells were separated by fluorescence-activated cell sorting into stromal mesenchymal cell (CD14-) and macrophage (CD14+) populations. CML and normal CD14- cells supported the growth of normal LTC-IC equally well. However, the addition of CML macrophages to normal or CML CD14- mesenchymal cells resulted in impaired progenitor support. This finding indicates that the abnormal function of CML bone marrow stroma is related to the presence of malignant macrophages. In contrast to normal LTC-IC, the growth of CML LTC-IC on allogeneic CML stromal layers was not impaired and was significantly better than that of normal LTC-IC cocultured with the same CML stromal layers. These studies demonstrate that, in addition to abnormalities in CML progenitors themselves, abnormalities in the CML marrow microenvironment related to the presence of malignant stromal macrophages may contribute to the selective expansion of leukemic progenitors and suppression of normal hematopoiesis in CML.  相似文献   
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Rothstein  G; Christensen  RD; Nielsen  BR 《Blood》1987,70(6):1836-1841
Clinical observations during infection suggest that in aged patients, the kinetic or proliferative responses of neutrophils to infection may be deranged. To test this hypothesis, the neutrophil responses of 6- month-old and 30-month-old mice were compared. After intrapulmonary injection of Escherichia coli, young mice exhibited neutrophilia and diminution of the neutrophil storage pool (NSP) by a mean of 6.4 x 10(6) neutrophils/two femurs. This was accompanied by an increase in the pool of CFU-GM from a control value of 1.1 x 10(5) cells/two femurs (range 0.7 to 1.4) to 1.5 x 10(5) (1.1 to 1.9) (P less than .05) and the thymidine suicide (relative proliferative rate) of CFU-GM rose from 27% (19 to 42) to 51% (31 to 61) (P less than .05). Furthermore, the CFU-GM of infected young mice displayed enhanced differentiation to the neutrophil series. In contrast, old mice exhibited a greater mean diminution of the NSP: 12.8 x 10(6) neutrophils. Also, old mice experienced a reduction in CFU-GM from 2.3 x 10(5) (1.0 to 3.9) (controls) to 1.3 x 10(5) (1.2 to 1.5)/two femurs (P less than .05), a reduction in the proliferation of CFU-GM and reduced differentiation of CFU-GM to neutrophils. These experiments establish that the neutrophil response of infected old mice is disordered, with exaggerated depletion of the NSP and lack of stimulus-driven granulocytopoiesis as reflected by a paradoxical reduction in the number and proliferative rate of precursors. This defect may be compounded by decreased differentiation of precursors to neutrophils.  相似文献   
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Altered mesolimbic dopamine signaling has been widely implicated in addictive behavior. For the most part, this work has focused on dopamine within the striatum, but there is emerging evidence for a role of the auto-inhibitory, somatodendritic dopamine D2 receptor (D2R) in the ventral tegmental area (VTA) in addiction. Thus, decreased midbrain D2R expression has been implicated in addiction in humans. Moreover, knockout of the gene encoding the D2R receptor (Drd2) in dopamine neurons has been shown to enhance the locomotor response to cocaine in mice. Therefore, we here tested the hypothesis that decreasing D2R expression in the VTA of adult rats, using shRNA knockdown, promotes addiction-like behavior in rats responding for cocaine or palatable food. Rats with decreased VTA D2R expression showed markedly increased motivation for both sucrose and cocaine under a progressive ratio schedule of reinforcement, but the acquisition or maintenance of cocaine self-administration were not affected. They also displayed enhanced cocaine-induced locomotor activity, but no change in basal locomotion. This robust increase in incentive motivation was behaviorally specific, as we did not observe any differences in fixed ratio responding, extinction responding, reinstatement or conditioned suppression of cocaine, and sucrose seeking. We conclude that VTA D2R knockdown results in increased incentive motivation, but does not directly promote other aspects of addiction-like behavior.  相似文献   
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Diaphragmatic lesions are usually congenital bronchogenic cysts. A patient with a known diaphragmatic cyst presented with new onset right upper quadrant pain. Repeat imaging showed enlargement of the cyst, the CA19–9 cancer marker was raised at 312iu/ml (normal: <27iu/ml) and positron emission tomography combined with computed tomography showed focally increased uptake in the cystic wall. In view of symptoms and risk of neoplasia, the lesion was excised. Histology showed a benign epidermoid cyst. Features falsely suggesting neoplasia have been reported previously with benign splenic cysts but not with a benign diaphragmatic epidermoid cyst.  相似文献   
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Aim

The aim of this case report was to show the importance to research metabolic etiology, especially a carnitine deficiency in dilated cardiomyopathy of children.

Case report

A three years old Togolese child presented muscular hypotonia, dyspnea. Examination showed left galop murmur and systolic murmur 2/6. Chest X-ray showed cardiomegaly (CTI: 0.66), electrocardiogram, a sinusal rythm, left ventricle hypertrophy and T wave abnormalities. Echocardiogram showed a markedly dilated left ventricle with reduced systolic function (EF: 0.43; reference range 0.55–0.80) and moderate mitral regurgitation. The inflammatory signs where negatives. Magnetic resonance imaging don’t show signs of ischemic or myocarditis. The levels of free and total plasmatic carnitine decreased: 3 μmol/L (N: 18–48 μmol/L) and 5 μmol/l (N: 29–70 μmol/L) respectively. Mutation analysis of the gene SLC22A5 confirms the diagnosis of primary systemic carnitine deficiency. Treatment with oral carnitine was started at 200 mg/kg per day. Within three weeks of treatment, we observed the decrease of all symptoms and the left ventricular size and function normalized (EF: 0.62). He has now been on oral carnitine for live.

Conclusion

Primary carnitine deficiency is a cause of dilated cardiomyopathy in child. It must systematically be suspected when a child presents a primitive cardiomyopathy. The treatment with oral carnitine for live is simple, with excellent prognosis.  相似文献   
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