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81.
Exhausted T cells and regulatory T (Treg) cells have been recently proposed to be new risk factors for recurrent miscarriage (RM). Intravenous immunoglobulin G (IVIG) treatment reported to modulate various immune cells. In this study, the effects of IVIG on the frequency and function of exhausted T cells, exhausted Tregs, and Treg cells, as well as pregnancy outcome in women with unexplained RM (URM), were investigated. Ninety-four pregnant women with RM were enrolled. At the time of positive pregnancy, blood samples were drawn. Forty-four patients with URM were included as IVIG receiving treated group and received 400 mg/kg of IVIG and the rest fifty patients were considered as a control group and received no IVIG administration. IVIG was given intravenously every 4 weeks during 32 weeks of gestation. Blood samples of patients were collected after the latest administration. Exhausted T cells, exhausted Tregs, and Treg cells were evaluated pre- and posttreatment in both groups. IVIG induced a significant decrease in the frequency of exhausted Tregs population and function as well as a significant increase in Treg cells population, however, IVIG failed to affect population and the function of exhausted T cells. Pregnancy outcome was successful in IVIG treated women (86.3%) and were significantly different (P = 0.0006) in compared with the untreated URM subjects (42%). Therefore, employing of IVIG increases Treg cells and diminishes exhausted Tregs responses in RM patients with cellular immune anomalies throughout the pregnancy. Immunemodulatory effects of IVIG are probably associated with successful pregnancy outcome.  相似文献   
82.
Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) can trigger a cytokine storm in the pulmonary tissue by releasing various types of mediators, leading to acute respiratory distress syndrome (ARDS). Increased neutrophil-to-lymphocyte ratio, as well as CD4+ T lymphopenia, is reported in cases with novel coronavirus disease (COVID-19), meanwhile, lymphopenia is a significant finding in the majority of COVID-19 cases with a severe phenotype. Moreover, excessive activation of monocyte/macrophage and cytokine storms are associated with the severity of the disease and the related complications in SARS-CoV-2 infection. Understanding the immune response dysregulation in COVID-19 is essential to develop more effective diagnostic, therapeutic, and prophylactic strategies in this pandemic.  相似文献   
83.
Tunisian pearl millet (Pennisetum glaucum L.) landraces are still growing in contrasting agro-ecological environments and are considered potentially useful for national and international breeders. Despite its genetic potential, the cropping areas of this species are still limited and scattered which increases the risk of genetic erosion. The chloroplast DNA polymorphism and maternal lineages classification of forty nine pearl millet landraces representing seven populations covering the main distribution area of this crop in Tunisia were undertaken based on informative cpSSR molecular markers. A total of 21 alleles combining to 9 haplotypes were detected with a mean value of 3.5 alleles per locus and a haplotype genetic diversity (Hd) of 0.82. The number of chloroplast haplotypes per population ranged from 1 to 4 with an average of 1.28. The haplotypes median-joining network and UPGMA analyses revealed two probable ancestral maternal lineages with a differential pearl millet seed-exchange rate between the investigated areas. Northern and Central populations presented unique genetic backgrounds while historical farmers’ practices in the South-East area resulted in the isolation of their own local landraces. The genetic evidences strongly support at least two introduction origins of pearl millet in Tunisia, one in the North and the other in the South followed by distinct local dispersal histories. Complementary in-situ and ex-situ conservation strategies taking into account the conservation of the maternal lineage cytoplasmic diversity are required. The investigated chloroplast SSRs provide useful molecular markers which could be used in further genetic studies and breeding surveys of pearl millet genetic resources.  相似文献   
84.
Journal of Plant Growth Regulation - Destruction caused by plant diseases is terrible. Mexican lime witches' broom (MLWB) is a phytoplasma disease, which has caused considerable damage...  相似文献   
85.
BackgroundThe management of gastric adenocarcinoma is essentially based on surgery followed by adjuvant treatment. Adjuvant chemotherapy (CT) as well as chemoradiotherapy (CTRT) have proven their effectiveness in survival outcomes compared to surgery alone. However, there is little data comparing the two adjuvant approaches. This study aimed to compare the prognosis and survival outcomes of patients with gastric adenocarcinoma operated and treated by adjuvant radio-chemotherapy or chemotherapyMaterials and methodsWe retrospectively evaluated 80 patients with locally advanced gastric cancer (LGC) who received adjuvant treatment. We compared survival outcomes and patterns of recurrence of 53 patients treated by CTRT and those of 27 patients treated by CT.ResultsAfter a median follow-up of 38.48 months, CTRT resulted in a significant improvement of the 5-year PFS (60.9% vs. 36%, p = 0.03) and the 5-year OS (55.9% vs. 33%, p = 0.015) compared to adjuvant CT. The 5-year OS was significantly increased by adjuvant CTRT (p = 0.046) in patients with lymph node metastasis, and particularly those with advanced pN stage (p = 0.0078) and high lymph node ratio (LNR) exceeding 25% (p = 0.012). Also, there was a significant improvement of the PFS of patients classified pN2–N3 (p = 0.022) with a high LNR (p = 0.018). CTRT was also associated with improved OS and PFS in patients with lymphovascular and perineural invasion (LVI and PNI) compared to chemotherapy.ConclusionThere is a particular survival benefit of adding radiotherapy to chemotherapy in patients with selected criteria such as lymph node involvement, high LNR LVI, and PNI.  相似文献   
86.
The K121Q polymorphism of the ectoenzyme nucleotide pyrophosphate phosphodiesterase 1 (ENPP1) gene has been variably associated with insulin resistance and type 2 diabetes (T2D) in several populations. However, this association has not been studied in Iranian subjects and we hypothesized that the K121Q variant might be associated with T2D and related metabolic traits in this population. The K121Q genotypes were determined by PCR-restriction fragment length polymorphism in 377 normoglycemic controls and 155 T2D patients. T2D patients had significantly higher values for systolic and diastolic blood pressure, BMI, glucose, cholesterol, triglyceride, LDL, apoB, insulin, and HOMA-IR, and lower levels of HDL than the normoglycemic subjects. The frequency of the Q allele did not differ between T2D and normoglycemic subjects (OR 0.96, 95% CI 0.90-2.00, P?=?0.70). The Q allele frequency was 16.5% in T2D and 15.2% in normoglycemic subjects. The ENPP1 genotype (KQ?+?QQ) was not associated with the systolic and diastolic blood pressure, glucose, triglyceride, cholesterol, LDL-C and HDL-C, apo B, BMI, HOMA-IR, and insulin levels in both normoglycemic and T2D groups. Our results suggest that the ENPP1 121Q allele might not be associated with T2D and related metabolic traits among Iranian subjects.  相似文献   
87.
We studied the diet, habitat use, and ranging behavior of 1 group of Callimico goeldii (callimicos) over 12 mo in northwestern Bolivia. The group’s diet was comprised of fungi (39%), fruits (31%), arthropods (14%), exudates (14%), and other matter (2%). Callimicos concentrated their ranging activities in secondary forest (50%), primary forest with dense understory (30%), and bamboo (17%) habitats. The group’s total home range was 114 ha; on average they used 38.4 ha/ mo and had a day range of 925 m. Monthly average day ranges—but not monthly home ranges—increased as frugivory declined, suggesting that subjects foraged on fungi and exudates by rechecking resources within a core area, making their day ranges longer than during months when they concentrated on fruit resources. The callimicos formed polyspecific associations with tamarins (Saguinus labiatus and S. fuscicollis) during 81% of observations. Day ranges increased in months with higher association rates which appears to result from the callimicos using a broader set of habitats when with tamarins than when alone. The ranging pattern of callimicos appears to be influenced primarily by 3 factors: their seasonal shift in diet requires that they forage in a variety of habitats across the year; their depletion of resources causes them to shift their core area over time; and their lack of territorial behavior eliminates the need to patrol boundaries as part of their daily movement. As a result, callimicos differ from many other callitrichids in their low ratio of day range length to home range size.  相似文献   
88.
Protein kinase D (PKD), also called protein kinase C (PKC)mu, is a serine-threonine kinase that is involved in diverse areas of cellular function such as lymphocyte signaling, oxidative stress, and protein secretion. After identifying a putative PKD phosphorylation site in the Toll/IL-1R domain of TLR5, we explored the role of this kinase in the interaction between human TLR5 and enteroaggregative Escherichia coli flagellin in human epithelial cell lines. We report several lines of evidence that implicate PKD in TLR5 signaling. First, PKD phosphorylated the TLR5-derived target peptide in vitro, and phosphorylation of the putative target serine 805 in HEK 293T cell-derived TLR5 was identified by mass spectrometry. Furthermore, mutation of serine 805 to alanine abrogated responses of transfected HEK 293T cells to flagellin. Second, TLR5 interacted with PKD in coimmunoprecipitation experiments, and this association was rapidly enhanced by flagellin treatment. Third, pharmacologic inhibition of PKC or PKD with G?6976 resulted in reduced expression and secretion of IL-8 and prevented the flagellin-induced activation of p38 MAPK, but treatment with the PKC inhibitor G?6983 had no significant effects on these phenotypes. Finally, involvement of PKD in the p38-mediated IL-8 response to flagellin was confirmed by small hairpin RNA-mediated gene silencing. Together, these results suggest that phosphorylation of TLR5 by PKD may be one of the proximal elements in the cellular response to flagellin, and that this event contributes to p38 MAPK activation and production of inflammatory cytokines in epithelial cells.  相似文献   
89.
Phytoplankton production and accumulation of extracellular organic carbon (EOC) was tracked during diel intervals in microcosms by inhibiting bacterioplankton assimilation of EOC with streptomycin and kanamycin. Bacterioplankton production (3H-thymidine incorporation) and metabolism (14C-glucose incorporation) were monitored in samples collected from the Potomac River estuary to determine the effect of the antibiotics. Particulate (i.e., raw water) primary production and EOC (i.e., water passing through 1.0 μm glass fiber filter) production rates were monitored to determine the impact of antibiotics on phytoplankton. In preliminary experiments, neither streptomycin nor kanamycin alone significantly inhibited bacterioplankton activity compared to controls, but when both were present secondary production and metabolism were reduced up to 90%, and remained as such for 45 h. During field evaluations using a streptomycin and kanamycin mixture (50 μM each) particulate primary production and EOC production were not statistically different in control and antibiotic treated samples indicating that the antibiotics did not negatively influence phytoplankton production rates. In the presence of antibiotics dissolved free amino acids (DFAA) and, to a lesser extent, monosaccharides were significantly elevated compared to controls. This study demonstrates that streptomycin and kanamycin are capable of inhibiting bacterioplankton metabolism and uptake of dissolved organic carbon (DOC) in the samples tested so that the contribution of EOC to the DOC pool and to bacterioplankton metabolism could be measured and assessed.  相似文献   
90.
The quality of signals received by dendritic cells (DC) in response to pathogens influences the nature of the adaptive response. We show that pathogen-derived signals to DC mediated via TLRs can be modulated by activated invariant NKT (iNKT) cells. DC maturation induced in vivo with any one of a variety of TLR ligands was greatly improved through simultaneous administration of the iNKT cell ligand alpha-galactosylceramide. DC isolated from animals treated simultaneously with TLR and iNKT cell ligands were potent stimulators of naive T cells in vitro compared with DC from animals treated with the ligands individually. Injection of protein Ags with both stimuli resulted in significantly improved T cell and Ab responses to coadministered protein Ags over TLR stimulation alone. Ag-specific CD8(+) T cell responses induced in the presence of the TLR4 ligand monophosphoryl lipid A and alpha-galactosylceramide showed faster proliferation kinetics, and increased effector function, than those induced with either ligand alone. Human DC exposed to TLR ligands and activated iNKT cells in vitro had enhanced expression of maturation markers, suggesting that a cooperative action of TLR ligands and iNKT cells on DC function is a generalizable phenomenon across species. These studies highlight the potential for manipulating the interactions between TLR ligands and iNKT cell activation in the design of effective vaccine adjuvants.  相似文献   
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