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991.
This study aimed to characterize astrocytic and microglial response in the central nervous system (CNS) of equines experimentally infected with T. evansi. The experimental group comprised males and females with various degrees of crossbreeding, ages between four and seven years. The animals were inoculated intravenously with 10(6) trypomastigotes of T. evansi originally isolated from a naturally infected dog. All equines inoculated with T. evansi were observed until they presented symptoms of CNS disturbance, characterized by motor incoordination of the pelvic limbs, which occurred 67 days after inoculation (DAI) and 124 DAI. The animals in the control group did not present any clinical symptom and were observed up to the 125th DAI. For this purpose the HE histochemical stain and the avidin biotin peroxidase method was used. Lesions in the CNS of experimentally infected horses were those of a wide spread non suppurative meningoencephalomyelitis.The severity of lesions varied in different parts of the nervous system, reflecting an irregular distribution of inflammatory vascular changes. The infiltration of mononuclear cells was associated with anisomorphic gliosis and reactive microglia was identified. The intensity of the astrocytic response in the CNS of the equines infected by T. evansi characterizes the importance of the performance of these cells in this trypanosomiasis. The characteristic gliosis observed in the animals in this experiment suggests the ability of these cells as mediators of immune response. The parasite, T. evansi, was not identified in the nervous tissues.  相似文献   
992.
We describe robust chemical approaches toward putative CCR5 scaffolds designed in our laboratories. Evaluation of analogues in the (125)I-[MIP-1beta] binding and Ba-L-HOS antiviral assays resulted in the discovery of 64 and 68 in the 4,4-disubstitited piperidine class H, both potent CCR5 ligands (pIC 50 = 8.30 and 9.00, respectively) and HIV-1 inhibitors (pIC 50 = 7.80 and 7.84, respectively, in Ba-L-HOS assay). In addition, 64 and 68 were bioavailable in rodents, establishing them as lead molecules for further optimization toward CCR5 clinical candidates.  相似文献   
993.
Verminoside and verbascoside are natural compounds present in plants used in traditional medicine. They exhibit several biological activities including anti-inflammatory, anti-bacterial and anti-tumor properties. The potential applications of these compounds as ingredients in pharmaceutical formulations and cosmetics prompted us to investigate on cytotoxic and genotoxic activity of verminoside and verbascoside on human lymphocytes using genetic toxicity assays recommended in preclinical studies by the US Food and Drug Administration (FDA). We analyzed chromosome aberrations (CAs) and sister chromatid exchanges (SCEs) as well as the mitotic index (MI) and cell viability after the treatments with verminoside and verbascoside. This report is the first to clearly demonstrate a significant increase of structural CAs and SCEs on normal human lymphocytes associated with a reduction of the MI in both verminoside- and verbascoside-treated cells. Moreover, we observed enhanced protein expression levels of PARP-1 and p53 that are key regulatory proteins involved in cell proliferation and DNA repair. Interestingly, mass spectrometric analysis of the compounds in the culture supernatants also showed that verminoside remained unchanged during the culture period while verbascoside was hydrolyzed to its derivative, caffeic acid and the last one seems to be responsible for the observed biological activity.  相似文献   
994.
The aim of study was to evaluate the clinicopathological features of oral mucoceles and the immunohistochemical expression of cellular and extracellular matrix components in these lesions. One hundred cases of oral mucoceles were examined for clinicopathological features. The expression of mast cell tryptase, CD68, MMP-1 (matrix metalloproteinase-1), MMP-9 (matrix metalloproteinase-9) and CD34 was investigated immunohistochemically in 32 cases. The lesions arose as nodules or blisters of variable color. The mean age was 23.2 years and a higher male frequency was observed. The most common locations were the lower lip (92%), followed by the floor of the mouth (7%), and palate (1%). The lesion size ranged from 0.4 to 3.0 cm. Unusual histopathological findings as superficial mucoceles (n = 16, 16%), pseudopapillary projections (n = 3, 3%), epithelioid histiocytes (n = 4, 4%), multinucleated giant cells (n = 1, 1%) and myxoglobulosis (n = 9, 9%) were also seen. Mast cells and CD68-positive macrophages, MMP-1, MMP-9 and CD34-positive blood vessels were seen in all cases. A significant association was seen between mast cells and MMP-1 (p = 0.03) and between macrophages and MMP-1 (p = 0.01). This study provided important insight into the demographic and histopathological occurrence of oral mucoceles. The tissue remodeling seen in these lesions mainly involved the migration and interaction of mast cells, macrophages and MMP-1.  相似文献   
995.

Purpose

Advances in reproductive techniques, mainly the introduction of oocyte vitrification, have provided the opportunity to conceive from oocyte banks. The aim of this study was to compare the clinical outcomes of fresh and vitrified oocytes in an egg donation program following blastocyst transfer.

Methods

This retrospective observational study included 504 oocyte donation cycles. All donor women were younger than 30 years of age. The recipient cycles were divided into two groups: fresh oocytes (n = 78) or vitrified oocytes (n = 426). All oocytes were fertilized by ICSI using ejaculated sperm, followed by blastocyst transfer. Endometrium preparation was performed with estradiol valerate plus micronized progesterone according to standard protocols.

Results

Recipients were of similar age (fresh 42.0 ± 4.5 years vs vitrified 41.8 ± 4.8 years; p = 0.790). The fresh group received more mature oocytes for injection compared to the vitrified group (10.1 ± 2.8 vs 9.2 ± 2.2; p = 0.005). The two pronuclei (2PN) rate (74.5 vs 77.4%; p = 0.195) and blastocyst rate (48.8 vs 51.6%; 0.329) were similar between the fresh and vitrified groups, respectively. The rates of clinical pregnancy were 60.9% in the fresh and 59.0% in the vitrified groups (p = 0.771).

Conclusions

Our findings suggest that vitrified oocytes result in similar pregnancy rates when compared to fresh oocytes with blastocyst transfer in an egg donation program. Moreover, vitrified oocytes may allow for a better cycle schedule, starting with a lower number of oocytes to be fertilized. Therefore, we hypothesize that egg banks with vitrified oocytes could be safely utilized in an egg donation program.
  相似文献   
996.
To determine the genetic variability of dengue viruses (DENVs) in Paraguay, the complete envelope gene was sequenced for 4 DENV-2 and 22 DENV-3 strains isolated from 2001 to 2006. The sequence data were used in Bayesian phylogenetic analyses, which revealed that Paraguayan DENV-2 strains fell into two distinct clades within the American/Asian genotype, thus suggesting that the introduction of a new DENV-2 clade was likely associated with the shift of dominant serotype from DENV-3 to DENV-2 in 2005 and might have caused an outbreak of DENV-2. This study also indicated that DENV-3 strains fell into genotype III, of which, several 2006 isolates varied from the remaining isolates in their tree locations. The introduction of this new clade was likely associated with the shift of dominant serotype from DENV-2 to DENV-3 in 2006 and might have caused an epidemic of DENV-3. More data are needed to test this hypothesis.  相似文献   
997.
Ageing is characterized by numerous changes in lymphocyte subpopulations. In the present paper we have focused on B cells carrying the surface markers CD27, CD5 and CD40. CD27 is considered a marker of primed (memory) cells and its engagement promotes the differentiation of memory B cells into plasma cells. CD5 is expressed on B1 cells, which are considered to be responsible for T cell-independent antibody production other than autoantibodies. The CD40 molecule binds CD40L (CD154) and is necessary for T-dependent antibody responses. Here we show that the absolute number of CD5+ and CD40+ B cells is decreased in the elderly, while CD27+ B lymphocytes only marginally decrease in centenarians. However, there is a decrease of the percentage of CD5+ B cells, an increase of CD27+ B cells, while CD40 does not change significantly. These data, together with the increased number of NK cells during aging, suggest different regulation of antibody production in the elderly which might be another example of immune remodeling with aging, based on interactions between human B and NK cells.  相似文献   
998.
ObjectivesThe purpose of this study was to examine the reliability of clinical measures related to forward shoulder posture (pectoralis minor index [PMI], scapular index [SI], abduction index [AI], acromion to the wall index [AWI] acromion to the treatment table index [ATI], and thoracic curvature [TC]), and to investigate the association (redundancy) among these measures.MethodsTwenty-one asymptomatic participants participated in this study. Two physiotherapists were trained to perform the clinical measurements. Intraclass correlation coefficients (ICC2,k) were calculated to assess intra- and interrater reliabilities. Pearson product moment correlation was used to investigate the existence of possible redundancy between the measures that showed high intra- and interrater reliabilities.ResultsThe measures showed ICCs between 0.30 and 0.97. Five measures, PMI, SI, AWI, ATI, and TC, showed appropriate values for intrarater reliability (ICCs 0.77-0.94), and 3 measures, AWI, ATI, and TC, for interrater reliability (ICCs 0.82-0.85). Among measures that showed acceptable intra- and interrater reliability values, 2 measures were redundant, showing high association (AWI vs ATI) (r = 0.80, P < .001).ConclusionFor PMI, SI, AWI, ATI, and TC measures, adequate values of intrarater reliability were observed. For AWI, ATI, and TC, adequate values of interrater reliability were found. Two pairs of measures were highly associated (PMI with SI; AWI with ATI), which indicates redundancy among them. Our results suggest that, when the same examiner performs the assessment, the combined use of the PMI, AWI, and TC measures allows a quick but comprehensive evaluation of the presence of forward shoulder posture.  相似文献   
999.
What is known and Objective: Rifampicin (RIF) shows wide variability in its pharmacokinetics. The purpose of this study was to develop and validate a population pharmacokinetic model to characterize the inter‐ and intra‐individual variability in pharmacokinetic parameters of RIF in Mexican patients. Methods: Ninety‐four patients receiving antituberculosis therapy participated in this prospective study. Plasma concentration‐time data were described using a one‐compartment model with lag time, absorption and first‐order elimination. The potential influence of demographic and clinical characteristics of the patients, and the pharmaceutical formulation (A, B, C and D) on the pharmacokinetics parameters, was evaluated by non‐linear mixed‐effect modelling (nonmem ). Seventy‐seven additional patients participated in the validation of the model. Results and Discussion: The final population pharmacokinetic model obtained was as follows: apparent clearance CL/F = 8·17 L/h (1·40 as high for males), apparent distribution volume Vd/F = 50·1 L (1·29 as high for males), absorption rate constant KaA = 0·391/h, KaB,C,D = 2·70/h, relative bioavailability FA = 0·468, FB,C,D = 1, lag time in the absorption phase Tlag = 0·264 h. The final model improved the precision on the parameter estimates (CL/F, Vd/F and Ka by 31·9%, 16·7% and 92·9%, respectively). The residual variability was 27·3%. What is new and Conclusion: Gender was associated with changes in CL/F and Vd/F whereas the pharmaceutical formulation was associated with changes in F and altered the Ka. The validation data set showed that the model could be used in clinical practice for Bayesian dose adjustment of RIF in TB patients.  相似文献   
1000.
We have previously demonstrated that a low dose of cyclophosphamide (Cy) combined with gene therapy of interleukin-12 (AdIL-12) has a synergistic, although limited, antitumoral effect in mice with colorectal carcinoma. The main mechanism involved in the efficacy of Cy+AdIL-12 was the induction of a specific immune response mediated by cytotoxic T lymphocytes. Our current aims were to evaluate the effects of 4-methylumbelliferone (4Mu), a selective inhibitor of hyaluronan (HA) synthesis, on tumor microenvironment (TME) and to investigate how 4Mu affects the therapeutic efficacy of Cy+AdIL-12. The results showed that 4Mu significantly reduced the amount of tumoral HA leading to a significant decrease in tumor interstitial pressure (TIP). As a consequence, tumor perfusion was improved allowing an increased adenoviral transgene expression. In addition, treatment with 4Mu boosted the number of cytotoxic T lymphocytes that reach the tumor after adoptive transfer resulting in a potent inhibition of tumor growth. Importantly, we observed complete tumor regression in 75% of mice when 4Mu was administrated in combination with Cy+AdIL-12. The triple combination 4Mu+Cy+AdIL-12 also induced a shift toward antiangiogenic factors production in tumor milieu. Our results showed that TME remodeling is an interesting strategy to increase the efficacy of anticancer immunotherapies based on gene and/or cell therapy.  相似文献   
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