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31.
Hemoderivative materials are used to treat different diseases. These derivatives include platelet-rich plasma, serum, platelet gel, and platelet lysate (PL). Among them, PL contains more growth factors than the others and its production is inexpensive and easy. PL is one of the proper sources of platelet release factors. It is used in cells growth and proliferation and is a good alternative to fetal bovine serum. In recent years, the clinical use of PL has gained more appeal by scientists. PL is a solution saturated by growth factors, proteins, cytokines, and chemokines and is administered to treat different diseases such as wound healing, bone regeneration, alopecia, oral mucositis, radicular pain, osteoarthritis, and ocular diseases. In addition, it can be used in cell culture for cell therapy and tissue transplantation purposes. Platelet-derived growth factor, fibroblast growth factor, insulin-like growth factor, transforming growth factor β, and vascular endothelial growth factor are key PL growth factors playing a major role in cell proliferation, wound healing, and angiogenesis. In this paper, we scrutinized recent advances in using PL and PL-derived growth factors to treat diseases and in regenerative medicine, and the ability to replace PL with other hemoderivative materials.  相似文献   
32.
Hsp90 chaperone complexes function in assembly, folding, and activation of numerous substrates. The 2 vertebrate homologues encoded by the genes hsp90a and hsp90b are differentially expressed in embryonic and adult tissues and during stress; however, it is not known whether they possess identical functional activities in chaperone complexes. This question was addressed by examining potential differences between the Hsp90 isoforms with respect to both cochaperone and substrate interactions. Epitope-tagged proteins were expressed in mammalian cells or Xenopus oocytes and subjected to immunoprecipitation with an array of cochaperones. Both isoforms were shown to participate equally in multichaperone complexes, and no significant differences in cochaperone distribution were observed. The substrates Raf-1, HSF1, Cdc37, and MEK1 interacted with both Hsp90alpha and Hsp90beta, and the relative patterns of these interactions were not affected by heat shock. The substrate kinases c-Src, CKIIB, A-raf, and Erk interacted with both isoforms; however, significantly more Hsp90alpha was recovered after heat shock. The data demonstrate that Hsp90alpha and Hsp90beta exhibit similar interactions with cochaperones, but significantly different behaviors with respect to substrate interactions under stress conditions. These results reveal both functional similarities and key functional differences in the individual members of this protein family.  相似文献   
33.
Background aimsTherapeutic promises of adult stem cells have been overshadowed by an elicited immune response, low maintenance of implanted cells or concerns regarding their migration to non-target sites. These problems might be lessened by the use of immune privilege cells and tissues for implantation.MethodsIn this study, human adipose-derived mesenchymal stromal cells (hADMSCs) were stably transfected with a vector containing Turbo green fluorescent protein (GFP) and JRed, which allows tracing the cells after transplantation. Labeled hADMSCs were transplanted into the adult rat brain followed by assessment of their survival and migration during 6 months after transplantation.ResultsResults indicate that there were no postsurgical complications, and the animals thrived after transplantation. The lesions of the surgical process were remarkable at the first weeks, and a high number of transplanted cells were accumulated around them. Cell populations declined over time as they partly migrated away from the injection sites; nonetheless, they were detectable at each examination time point. Although the cells could survive and remain at the injection site for up to 6 months, some of them drifted to spleen, which is an indication of their ability to cross the blood-brain barrier.ConclusionsDespite the high survival rate of hADMSCs in the xenogenic condition, which is an ideal criterion in cell therapy, irregular migration tendency must be handled with caution.  相似文献   
34.

Introduction

The result of recent genome-wide association studies revealed that, in addition to HLA-B27, a few non-HLA genes are associated with susceptibility to ankylosing spondylitis (AS) in Caucasian populations. According to these studies, IL-23R is one of the genes that is associated with AS. In this study, we evaluated five important single nucleotide polymorphisms (SNPs) of the IL-23R gene which confers susceptibility to AS, and its effects on the severity of the disease in HLA-B27 positive and negative patients and several subtypes of HLA-B27.

Materials and methods

The study population consisted of 294 AS patients and 352 age-, sex-, and ethnicity-matched healthy controls. All patients were examined by rheumatologists, and met modified,NewYork criteria for the disease. Five SNPs (rs1004819, rs11209032, rs1495965, rs11465804, and rs1004819) of the IL-23R gene were genotyped using the Real-Time PCR TaqMan genotyping method.

Results

We found that only rs1004819 has a significant association with AS, and that the remaining four SNP alleles are not associated with AS. Also, there was no association between these five polymorphisms and BASDAI, BASFI, and BASMI indices. Two haplotypes, ACGAT and ACGAG, were found to be associated with the heritability of AS. In addition, two significant, protective diplotypes (D8, \(\frac{{GCGAG}}{{GTGGG}}\); and D9, \(\frac{{ACGAG}}{{GCGAG}}\)) were discovered.

Conclusion

This study supported our previous findings regarding the differences between the genetic patterns of AS in Iranian patients compared with those in other parts of the world.
  相似文献   
35.
Sistan and Baluchestan province, South-East of Iran, has been reported as an endemic area of malaria [Sadrizadeh B. Malaria in the world, in the eastern Mediterranean region and in Iran: Review article. WHO/EMRO Report 2001: 1-13.]. The main objective of this research was to perform rapid and correct diagnoses of malaria infection. Blood specimens were collected from 140 suspected volunteers. The Giemsa-stained slides examination and nested PCR for amplification of the Plasmodium small subunit ribosomal genes (ssrRNA) were utilized. The results demonstrated 118 out of 140 cases (84.3%) positive for malaria parasites, including 60.7%, 20.7% and 2.9% as having Plasmodium vivax (P.v), Plasmodium falciparum (P.f) and mixed infections (P.v+P.f), respectively by microscopy. The nested PCR detected malaria parasites in 134 samples (94.3%), consisting of 51.4% P.v, 12.6% P.f and 29.3% mixed infections. The PCR analysis detected 37 cases of mixed infections more than that of the routine microscopy. These results suggested that there are a considerable number of cases with mixed infections in the study area that mainly remain undiagnosed by microscopy. It is also concluded that the nested PCR is a suitable complement to microscopy for accurate specific diagnosis of malaria species in field.  相似文献   
36.
Toxoplasma gondii is one of the major agents of infectious abortions and due to its worldwide distribution can threat healthy pregnant women who had no previous exposure to this parasite. The present study was designed to investigate the contribution of T. gondii to spontaneous abortions in Zanjan, Northwest of Iran, using ELISA method. Blood Samples were collected from 264 mothers referred to the provincial hospitals of Zanjan due to spontaneous abortion. The sera were isolated and subjected to evaluate the anti-Toxoplasma IgG, IgM and IgA antibodies. The results showed IgG positive (IgG+) in 99 cases (37.5%). A total of 68 women (25.8%) showed seroconversion with IgM or IgA or both IgM and IgA. They included: IgM+ in 21 (8.0%), IgA+ in 23 (8.7%) and both IgM+ and IgA+ in 24 (9.1%) subjects. In 23 cases, positive titers of IgM and IgG were accompanied. In general, the analysis of anti-Toxoplasma antibody patterns, showed that about 17% of the spontaneous abortions were associated with serological patterns of acute infection. According to these findings, a considerable proportion of spontaneous abortions can be attributed to T. gondii in the study area.  相似文献   
37.

Background

Maternal epileptic seizures during pregnancy can affect the hippocampal neurons in the offspring. The polysialylated neural cell adhesion molecule (PSA-NCAM), which is expressed in the developing central nervous system, may play important roles in neuronal migration, synaptogenesis, and axonal outgrowth. This study was designed to assess the effects of kindling either with or without maternal seizures on hippocampal PSA-NCAM expression in rat offspring.

Methods

Forty timed-pregnant Wistar rats were divided into four groups: A) Kind+/Seiz+, pregnant kindled (induced two weeks prior to pregnancy) rats that received repeated intraperitoneal (i.p.) pentylenetetrazol, PTZ injections on gestational days (GD) 14-19; B) Kind-/Seiz+, pregnant non-kindled rats that received PTZ injections on GD14-GD19; C) Kind+/Seiz-, pregnant kindled rats that did not receive any PTZ injections; and D) Kind-/Seiz-, the sham controls. Following birth, the pups were sacrificed on PD1 and PD14, and PSA-NCAM expression and localization in neonates’ hippocampi were analyzed by Western blots and immunohistochemistry.

Results

Our data show a significant down regulation of hippocampal PSA-NCAM expression in the offspring of Kind+/Seiz+ (p = 0.001) and Kind-/Seiz+ (p = 0.001) groups compared to the sham control group. The PSA-NCAM immunoreactivity was markedly decreased in all parts of the hippocampus, especially in the CA3 region, in Kind+/Seiz+ (p = 0.007) and Kind-/Seiz+ (p = 0.007) group’s newborns on both PD1 and 14.

Conclusion

Our findings demonstrate that maternal seizures but not kindling influence the expression of PSA-NCAM in the offspring’s hippocampi, which may be considered as a factor for learning/memory and cognitive impairments reported in children born to epileptic mothers.  相似文献   
38.
The utility of sequence polymorphisms in the dense granule antigen GRA6 gene as typing markers for Toxoplasma gondii was investigated. The coding region of GRA6 was amplified, sequenced and compared for 30 Toxoplasma strains from eight different zymodemes (Z1-Z8). Sequence alignment identified nucleotide polymorphisms at 24 positions out of 690 bp, which correlated with murine-virulence. Types I, II, and III could be distinguished from each other on the basis of three, 10, and six variable positions, respectively. Two deletions of 15 bp and 3 bp existed in the avirulent (type II) strains. With one exception, all polymorphic positions resulted in amino acid substitutions, and the two gaps of 15 bp and 3 bp caused the deletion of six amino acids in type II strains. Intra-specific polymorphisms were also found in the virulent group. A high degree of sequence polymorphism correlating with the phenotypes of T. gondii strains points to the GRA6 gene being a good marker for strain characterisation and typing of the isolates of this apicomplexan. The large variety of amino acid changes supports the view that the GRA6 protein plays an important role in the antigenicity and pathogenicity of T. gondii. The existence of polymorphic restriction sites for endonuclease MseI was used to develop a PCR-RFLP method which could simply differentiate the three different groups (types I, II, III) of T. gondii.  相似文献   
39.
The effects of long term salinity on some morpho-physiological characteristics were studied in strawberry Kurdistan and Queen elisa cultivars. Vegetative and biochemical traits were measured in strawberry cultivars subjected to three levels of salinity including 0, 40 and 80 mM at 20, 40 and 60th days after NaCl addition. Results showed that in both cultivars the dry weight of plant organs decreased in response to NaCl, except of crown weight in cv. Kurdistan. Root to shoot ratio increased due to a greater reduction in above ground biomass under salinity. Strawberry cultivars tended to decrease their stomatal conductance, RWC, proline, soluble carbohydrates and proteins during the different evaluation periods. Compared to the 20th day, peroxidase activity decreased at 80 mM during 40 and 60 days in cv. Queen elisa. On the contrary, ascorbate peroxidase activity elevated until the 40th day and decreased afterwards, in addition application of 40 and 80 mM NaCl increased the ascorbate peroxidase activity of both studied cultivars. Catalase activity increased from 20th until 60th days in cv. Queen elisa, while showed increase in cv. Kurdistan until day 40 and then decreased again at day 60. Application of 40 and 80 mM NaCl resulted in an increase in peroxidase, ascorbate peroxidase and catalase activities of both cultivars. The Queen elisa cv. showed lower tolerance index (45.88%) compared with cv. Kurdistan (67.97%). Finally, higher salinity resistance of cv. Kurdistan is probably associated with its ability to maintain higher RWC and higher activity of antioxidant enzymes.  相似文献   
40.
Adipose derived mesenchymal stem cells (ASCs) transplantation is a novel immunomodulatory therapeutic tool to ameliorate the symptom of inflammatory bowel disease (IBD). The objective of this study was to investigate the therapeutic effects of combined sufasalazine and ASCs therapy in a rat model of IBD. After induction of colitis in rats, ASCs were cultured and intraperitoneally injected (3 × 106cells/kg) into the rats on Days 1 and 5 after inducing colitis, in conjunction with daily oral administration of low dose of sulfasalazine (30 mg/kg). The regenerative effects of combination of ASCs and sulfasalazine on ulcerative colitis were assessed by measuring body weight, colonic weight/length ratio, disease activity index, macroscopic scores, histopathological examinations, cytokine, and inflammation markers profiles. In addition, western blot analysis was used to assess the levels of nuclear factor-kappa B (NF-κB) and apoptosis related proteins in colitis tissues. Simultaneous treatment with ASCs and sulfasalazine was associated with significant amelioration of disease activity index, macroscopic and microscopic colitis scores, as well as inhibition of the proinflammatory cytokines in trinitrobenzene sulfonic acid (TNBS)-induced colitis. Moreover, combined ASCs and sulfasalazine therapy effectively inhibited the NF-κB signaling pathway, reduced the expression of Bax and prevented the loss of Bcl-2 proteins in colon tissue of the rats with TNBS-induced colitis. Furthermore, combined treatment with ASCs and sulfasalazine shifted inflammatory M1 to anti-inflammatory M2 macrophages by decreasing the levels of MCP1, CXCL9 and increasing IL-10, Arg-1 levels. In conclusion, combination of ASCs with conventional IBD therapy is potentially a much more powerful strategy to slow the progression of colitis via reducing inflammatory and apoptotic markers than either therapy alone.  相似文献   
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