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1.
Overexpression of wound healing-promoting factors such as transforming growth factor-1 (TGF-beta1) and insulin-like growth factor-1 (IGF-1) during the healing process has been implicated in the development of dermal fibrosis in patients following thermal injury, surgical incision, and deep trauma. However, the mechanism through which the expression of these two fibrogenic factors is slowed down and/or abrogated in the late stages of the healing process is not known. Here, we hypothesize that keratinocyte-releasable factors counteract the fibrogenic role of both IGF-1 and TGF-beta1 in fibroblasts. To test this hypothesis, the levels of collagenase (MMP-1), as an index for extracellular matrix degradation, in dermal fibroblasts in response to either keratinocyte-conditioned medium (KCM) or our recently identified keratinocyte-releasable stratifin in the presence and absence of either IGF-1, TGF-beta1, or both were evaluated. The results of Northern analysis showed a significant increase in collagenase mRNA expression in cells treated with KCM in the presence of both IGF-1 and TGF-beta1. The effect was, at least in part, due to keratinocyte-derived stratifin that was present in KCM. This was ascertained as the levels of MMP-1 mRNA were markedly reduced when cells were treated with stratifin-immuno-depleted KCM. The results of Western blot analysis showed an increase in the level of MMP-1 protein in stratifin-treated fibroblasts and this was consistent with the level of MMP-1 mRNA expression detected by Northern analysis. However, in contrast to KCM, whose efficacy on MMP-1 expression was modestly reduced by either IGF-1 and TGF-beta1, or a combination of both, these factors abrogated the MMP-1 stimulatory effect of stratifin in fibroblasts. In summary, the results of this study revealed that both stratifin and KCM stimulate the expression of MMP-1-in fibroblasts and this effect can be abrogated by either IGF-1, TGF-beta1, or a combination of both.  相似文献   
2.
We report on a patient with a rec(20)dup(20q) chromosome abnormality derived from a paternal chromosome 20 inversion [inv(20)(p13q13.1)]. The rearrangement results in a duplication of 20q13.1 to 20qter and a deletion of 20p13 to 20pter. The patient is a girl with craniofacial features and multiple congenital malformations that overlap with the abnormalities previously described in trisomy 20q syndrome. To our knowledge this is the first report of a patient with rec(20)dup 20q.  相似文献   
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The aim of this study was to evaluate the biochemical changes in cobalt-exposed rats and to investigate the potential role of Tunisian propolis against the cobalt-induced renal damages. Twenty-four pregnant Wistar rats were divided into four groups and were treated as follows: group 1 (control) received distilled water; group 2 received 350 ppm of CoCl2 in drinking water; group 3 received 350 ppm CoCl2 in drinking water and a propolis-supplemented diet (1 g/100 g of diet); group 4 received a propolis-supplemented diet (1 g/100 g of diet) without cobalt. In the cobalt group, a significant decrease in body, absolute and relative weights was noted when compared to controls. The administration of cobalt to pregnant rats from the 14th day of pregnancy until day 14 after delivery resulted in an increased level of renal malondialdehyde, a decreased renal content of glutathione and antioxidant enzyme activities such as superoxide dismutase, catalase and glutathione peroxidase in lactating rats and their pups. A statistically significant increase in plasma urea and creatinine serum levels was seen in treated female rats and their pups. Histopathologically, the cobalt-administration induced degenerative changes in the kidney of lactating rats and their pups. When compared with cobalt-treated rats, those receiving the propolis supplementation (along with cobalt-treatment) had lower malondialdehyde levels, higher antioxidant activities and the cobalt-related histopathological changes in the kidneys were at lower severity.Our results suggested that the propolis might be a potential candidate agent against cobalt-induced nephrotoxicity in adult and juvenile rats when administered to female rats during the late pregnancy and the early postnatal period.  相似文献   
7.

Background

Studies exploring the knowledge, attitude and patterns of OCs use among women in Jordan are lacking. The aim of this study was to assess knowledge, attitude, and patterns of oral contraceptives (OCs) utilization among women in Jordan.

Methods

A face-to-face questionnaire inquiring demographic information and issues related to knowledge and use of OCs was completed by women (n?=?1571), who have had used OCs at least once in their lifetime. A model was created to assess the effects of knowledge, attitude and previous experience on the patterns of OCs utilization.

Results

Jordanian women exhibited positive attitudes towards OCs efficacy and safety. This positive attitude was approvingly associated with the patterns of use. However, only half of participating women reported that they knew how to use OCs. About 60 % of women received recommendations for OCs use from a physician. Moreover, women’s knowledge about OCs mechanism of action was obtained namely from physician (29.9 %). Side effects were reported in 75.1 % of participating women. Reported side effects were headache (41.2 %), mood swings (35.5 %), irritability (33.5 %) and weight gain (28.7 %). Interestingly, the occurrence of side effects was the main reason for OCs discontinuation.

Conclusion

The study showed that women who have positive attitude toward OCs tend to utilize them more appropriately. However, there is still need for educational programs to enhance knowledge about OCs utilization in Jordan.
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8.
The purpose of this study was to evaluate in a retrospective analysis, cases of Mediterranean visceral leishmaniasis (VL) diagnosed in adults during a 20-year period in a department of infectious diseases. Demographic data, clinical and laboratory features and therapeutic findings were considered. During the study period, 22 cases of VL were diagnosed, and 6 (27%) were associated with HIV infection. Fever and splenomegaly were observed in all cases. Anaemia was constant. The anti-leishmanial IF titer was positive among 21 patients (95%). Smears from bone marrow aspiration were positive at microscopy in 95% of cases. Zymodeme analysis was carried out in nine isolates. L. infantum zymodeme MON-1 was characterized in all cases. Seventeen patients (77%) received meglumine antimoniate (MA) (20 mg SbV/kg per day) and 5 (23%) patients amphotericin B (AB) (0.5-1 mg/kg per day) for an average period of 25 days (10-49 days). Adverse events occurred in 7 patients (32%), among them 4 received AB. Clinical cure was achieved with success in 21 patients (95%). After a successful MA treatment of the initial episode, VL relapse was observed in one HIV-positive patient. Only one HIV-positive patient died from neurological disorders. VL is rare in adults. However, its incidence is increasing everywhere in the world, because of HIV-related cases. Its prognosis depends on the precocity of diagnosis and treatment.  相似文献   
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Bone marrow-derived stem cells have the potential to transdifferentiate into unexpected peripheral cells. We hypothesize that circulating bone marrow-derived stem cells might have the capacity to transdifferentiate into epithelial-like cells and release matrix metalloproteinase-1-modulating factors such as 14-3-3varsigma for dermal fibroblasts. We have characterized a subset of peripheral blood mononuclear cells (PBMCs) that develops an epithelial-like profile. Our findings show that these cells develop epithelial-like morphology and express 14-3-3varsigma and keratin-5, -8 as early as day 7 and day 21, respectively. When compared with control, conditioned media collected from PBMCs in advanced epithelial-like differentiation (cultures on days 28, 35, and 42) increased the matrix metalloproteinase-1 expression in dermal fibroblasts (P 相似文献   
10.
This article proposes a Fuzzy Second Order Integral Terminal Sliding Mode (FSOITSM) control approach for DFIG-based wind turbines subject to grid faults and parameter variations. Since traditional terminal sliding mode control (SMC) suffers from singularity, a novel integral terminal sliding manifold is proposed to eliminate chattering and improve the wind turbine's performance in the presence of faults and disturbances. A fuzzy system is proposed to auto-tune the controllers' gains and ensures the invariance of the sliding surfaces even under heavy uncertainties, thus further improving the reliability and performance of the proposed controller. The performance of the proposed approach was assessed under various operating conditions. A comparison analysis with a standard SMC approach as well as the state of the art in voltage sag mitigation was also carried over. Reliability, robustness, and power availability under faulty grid conditions are among the main features of the proposed approach. In addition, the proposed approach exhibited chattering free dynamics and enabled the finite time convergence of the sliding manifold and overcame the singularity problem associated with standard TSMC.  相似文献   
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