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41.

Background

Leishmaniasis has been identified as a major public health problem in tropical and sub-tropical countries. The present study was aimed to investigate antileishmanial effects of various extracts of Berberis vulgaris also its active compoenent, berberine against Leishmania tropica and L. infantum species on in vitro experiments.

Methods

In this study in vitro antileishmanial activity of various extracts of B. vulgaris also its active compoenent, berberine against promastigote and amastigote stages of L. tropica and L. infantum was evaluated, using MTT assay and in a macrophage model, respectively. Furthermore, infectivity rate and cytotoxicity effects of B. vulgaris and berberine in murine macrophage cells were investigated.

Results

The findings of optical density (OD) and IC50 indicated that B. vulgaris particulary berberine significantly (P<0.05) inhibited the growth rate of promastigote stage of L.tropica and L.infantum in comparison to meglumine antimoniate (MA). In addition, B. vulgaris and berberine significantly (P<0.05) decreased the mean number of amastigotes in each macrophage as compared with positive control. In the evaluation of cytotoxicity effects, it could be observed that berberine as compared with B. vulgaris exhibited more cytotoxicity against murine macrophages. Results also showed that when parasites were pre-incubated with B. vulgaris their ability to infect murine macrophages was significantly decreased.

Conclusion

B.vulgaris particularly berberine exhibited potent in vitro leishmanicidal effects against L. tropica and L.infantum. Further works are required to evaluate the antileishmanial effects of B.vulgaris on Leishmania species using clinical settings.  相似文献   
42.

Background

Toxoplasmosis is a worldwide spread disease. The present study examined the prevalence of Toxoplasma gondii infection among animals of edible meat (cattle and sheep) in Chaharmahal va Bakhtiari Province (Southwest of Iran) in 2012. Furthermore, we attempted for the first time to identify this parasite from the meat products in the province.

Methods

The tongue, brain, femur muscle and liver of 50 sheep and 70 cattle as well as 50 samples of meat products were selected and collected to perform molecular survey using Nested-PCR method.

Results

Of the studied sheep, 38% were infected. The infection rate in the age groups under 1 year, 1-2 years, and more than 2 years was 25%, 35.29% and 52.94%, respectively. The infection rate in femur muscle, brain, liver and tongue was 28%, 32%, 30% and 16%, respectively. Of the studied cattle, 8.57% were infected. The infection rate in the age groups 1-2 years, 2-4 years, and more than 4 years was 3.7%, 9.09% and 14.28%, respectively. Sheep was infected 6 times more than cattle (OR = 6.53 CI = 2.374-18.005).The infection rate among samples of meat products was 12% (6 samples out of 50 samples).

Conclusion

Due to the high rate of this parasitic infection among the slaughtered animals as well as meat products in this region, the use of infected material can be one of the main risk factors of transmission of the parasite to humans.  相似文献   
43.
One of the rarest forms of chronic granulomatous disease (CGD) is caused by mutations in CYBA, which encodes the p22-phox subunit of the phagocyte NADPH oxidase, leading to defective intracellular killing. This study investigated eight patients (six males and two females) from seven consanguineous, unrelated families with clinical CGD, positive family history and p22-phox deficiency. Mutation analysis of CYBA showed six different novel mutations: deletion of exons 3, 4 and 5; a missense mutation in exon 6 (c.373G>A); a splice site mutation in intron 5 (c.369+1G>A); a frameshift in exon 6 (c.385delGAGC); a frameshift in exon 3 (c.174delG); and a frameshift in exon 4 (c.223delC).  相似文献   
44.
Mitochondrial injury in steatohepatitis   总被引:9,自引:0,他引:9  
Rich diet and lack of exercise are causing a surge in obesity, insulin resistance and steatosis, which can evolve into steatohepatitis. Patients with non-alcoholic steatohepatitis have increased lipid peroxidation, increased tumour necrosis factor-alpha (TNF-alpha) and increased mitochondrial beta-oxidation rates. Their in-vivo ability to re-synthesize ATP after a fructose challenge is decreased, and their hepatic mitochondria exhibit ultrastructural lesions, depletion of mitochondrial DNA and decreased activity of respiratory chain complexes. Although the mechanisms for these effects is unknown, the basal cellular formation of reactive oxygen species (ROS) may oxidize fat deposits to cause lipid peroxidation, which damages mitochondrial DNA, proteins and cardiolipin to partially hamper the flow of electrons within the respiratory chain. This flow may be further decreased by TNF-alpha, which can release cytochrome c from mitochondria. Concomitantly, the increased mitochondrial fatty acid beta-oxidation rate augments the delivery of electrons to the respiratory chain. Due to the imbalance between a high electron input and a restricted outflow, electrons may accumulate within complexes I and III, and react with oxygen to form the superoxide anion radical. Increased mitochondrial ROS formation could in turn directly oxidize mitochondrial DNA, proteins and lipids, enhance lipid peroxidation-related mitochondrial damage, trigger hepatic TNF-alpha formation and deplete antioxidants, thus further blocking electron flow and further increasing mitochondrial ROS formation. Mitochondrial dysfunction plays an important role in liver lesions, through the ROS-induced release of both biologically active lipid peroxidation products and cytokines. In particular, the up-regulation of both TNF-alpha and Fas triggers mitochondrial membrane permeability and apoptosis. The ingestion of apoptotic bodies by stellate cells stimulates fibrogenesis, which is further activated by lipid peroxidation products and high leptin levels. Chronic apoptosis is compensated by increased cell proliferation, which, together with oxidative DNA damage, may cause gene mutations and cancer.  相似文献   
45.
Bendamustine + rituximab (BR) is the current first-line standard-of-care for chronic lymphocytic leukaemia (CLL) in fit patients aged 66–70 years, whereas chlorambucil + CD20 antibody is recommended in older patients with co-morbidities. This retrospective real-world study investigated whether risk-adapted BR was safe and effective in elderly patients. All 141 CLL patients in the Stockholm region (diagnosed from 2007 to 2016, identified from regional registries) who had received BR as first (n = 84) or later line (n = 57) were analysed. Median age was 72 years, 49% had Binet stage C, 40% had Cumulative Illness Rating Scale (CIRS) score ≥ 6, 20% Eastern Cooperative Oncology Group (ECOG) score 2. None had del(17p). Only 15% of patients aged ≥80 years received full-dose bendamustine and 65% of them postponed rituximab until cycle 2. Corresponding numbers in patients 73–79 years were 21% and 36% and in <73 years, 63% and 33%. Overall response rate was 83% (first line) and 67% (later line) (P < 0·022) equally distributed between age subsets. ECOG, immunoglobulin heavy chain variable region (IGHV) mutational status and cytogenetics, but not treatment line and age, were significant factors on progression-free survival (PFS) in multivariate analysis. Infections and neutropenia/thrombocytopenia (≥grade 3) were similar across age subgroups. In summary, BR was well tolerated even in patients ≥80 years, with similar efficacy and safety as in less old patients, provided that carefully adapted dosing was applied.  相似文献   
46.
BackgroundEndometriosis can lead to infertility. Since there is no definitive treatment for endometriosis, animal modelling seems necessary to examine the possible treatments. Mouse endometrium cannot be separated for endometriosis induction. In addition, transplantation of uterus into the abdominal viscera to induce endometriosis causes organ damage. In this study, we defined a new model of endometriosis leading to separability of endometrium and a safe anatomical region for transplantation.MethodsForty female mice were allocated to 5 groups: 1, sham; 2, allograft uterus transplantation of mice to anterior abdominal wall of mice; 3, allograft uterus transplantation of mice to mesentery of mice; 4, xenograft endometrial transplantation of rat to anterior abdominal wall of mice; 5, xenograft endometrial transplantation of rat to mesentery of mice. Adult female rats with a previous pregnancy experience were selected and placed in the vicinity of male rats for 2 weeks to induce estrogen secretion and increase endometrial thickness.ResultsIn the 4th group of animals, compared to sham, the peritoneal concentrations of VEGF‐A, TNF‐α, NO, MDA, and serum levels of CA‐125 and IL‐37 were increased and total body weight was decreased, while weight and size of endometrial lesions were increased significantly (P < .05). Genes expression of HOXA10 and HOXA11 were decreased significantly (P < .05) in groups 2 and 4 compared to sham.ConclusionsXenograft transplantation of endometrium from rat to anterior abdominal wall of mice can potentially mimic human endometriosis morphologically, histologically, and genetically.  相似文献   
47.
目的探讨呼吸机致肺损伤时血清中细胞因子是否增高及其机制。方法通过呼吸机诱导肺损伤的体内及体外模型,将分离的肺泡上皮细胞于体外拉长,利用基因微阵列技术分析并筛选出上调的炎性细胞因子,之后给予大鼠呼吸机机械通气,留取血清标本,测量这些细胞因子在血清中是否上调。我们在体外培养的肺上皮细胞中加入外源性肿瘤坏死因子、过氧化氢或N-乙酰半胱氨酸,观察细胞因子的变化。N-乙酰半胱氨酸亦被投入大鼠呼吸机诱导肺损伤模型,观察用药后细胞因子的变化。结果转移生长因子β1(TGF-β1)和转移生长因子β2(TGF-β2)在体外拉长的肺上皮细胞中表达增加,并且在大潮气量机械通气的大鼠血清中浓度增加。肿瘤坏死因子不能改变TGF-β的表达,而过氧化氢诱导了TGF-β的上调。N-乙酰半胱氨酸减轻氧自由基损伤,不论在体内或体外试验中均阻断了过度拉长所致TGF-β在细胞及大鼠血清中的上调。结论TGF-β1和TGF-β2在通气机所致肺损伤中的表达增加并在血清中上调;TGF-β上调的机制与氧自由基损伤有关但与肿瘤坏死因子无关;N-乙酰半胱氨酸可对抗氧自由基损伤,能阻断TGF-β的上调,可能成为呼吸机相关肺损伤的一种新治疗途径。  相似文献   
48.
Next-generation sequencing has revealed novel recurrent mutations in chronic lymphocytic leukemia, particularly in patients with aggressive disease. Here, we explored targeted re-sequencing as a novel strategy to assess the mutation status of genes with prognostic potential. To this end, we utilized HaloPlex targeted enrichment technology and designed a panel including nine genes: ATM, BIRC3, MYD88, NOTCH1, SF3B1 and TP53, which have been linked to the prognosis of chronic lymphocytic leukemia, and KLHL6, POT1 and XPO1, which are less characterized but were found to be recurrently mutated in various sequencing studies. A total of 188 chronic lymphocytic leukemia patients with poor prognostic features (unmutated IGHV, n=137; IGHV3-21 subset #2, n=51) were sequenced on the HiSeq 2000 and data were analyzed using well-established bioinformatics tools. Using a conservative cutoff of 10% for the mutant allele, we found that 114/180 (63%) patients carried at least one mutation, with mutations in ATM, BIRC3, NOTCH1, SF3B1 and TP53 accounting for 149/177 (84%) of all mutations. We selected 155 mutations for Sanger validation (variant allele frequency, 10–99%) and 93% (144/155) of mutations were confirmed; notably, all 11 discordant variants had a variant allele frequency between 11–27%, hence at the detection limit of conventional Sanger sequencing. Technical precision was assessed by repeating the entire HaloPlex procedure for 63 patients; concordance was found for 77/82 (94%) mutations. In summary, this study demonstrates that targeted next-generation sequencing is an accurate and reproducible technique potentially suitable for routine screening, eventually as a stand-alone test without the need for confirmation by Sanger sequencing.  相似文献   
49.
A review of the literature on restoration of endodontically treated teeth was presented. The advantages and disadvantages of current methods and materials were described, and a detailed technique was suggested for the newer glass-ionomer restorative materials. An all-purpose material suited for the restoration of endodontically treated teeth is still unavailable. Each patient requires individual consideration. However, Ketac Silver material may be an excellent choice in select patients.  相似文献   
50.
An alternative to cast etched retainers   总被引:1,自引:0,他引:1  
  相似文献   
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