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61.
This report describes the isolation of Aeromonas veronii biovar sobria as the causative enteropathogen of diarrhoea in an oncological patient after failure of detection of other infectious agents. The case points out the severe and long course of the infection, the diagnostic dilemma, and the prompt recovery after antibiotic treatment.  相似文献   
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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   
64.
Ionizing radiation plays a central role in several medical and industrial purposes. In spite of the beneficial effects of ionizing radiation, there are some concerns related to accidental exposure that could pose a threat to the lives of exposed people. This issue is also very critical for triage of injured people in a possible terror event or nuclear disaster. The most common side effects of ionizing radiation are experienced in cancer patients who had undergone radiotherapy. For complete eradication of tumors, there is a need for high doses of ionizing radiation. However, these high doses lead to severe toxicities in adjacent organs. Management of normal tissue toxicity may be achieved via modulation of radiation responses in both normal and malignant cells. It has been suggested that treatment of patients with some adjuvant agents may be useful for amelioration of radiation toxicity or sensitization of tumor cells. However, there are always some concerns for possible severe toxicities and protection of tumor cells, which in turn affect radiotherapy outcomes. Selenium is a trace element in the body that has shown potent antioxidant and radioprotective effects for many years. Selenium can potently stimulate antioxidant defense of cells, especially via upregulation of glutathione (GSH) level and glutathione peroxidase activity. Some studies in recent years have shown that selenium is able to mitigate radiation toxicity when administered after exposure. These studies suggest that selenium may be a useful radiomitigator for an accidental radiation event. Molecular and cellular studies have revealed that selenium protects different normal cells against radiation, while it may sensitize tumor cells. These differential effects of selenium have also been revealed in some clinical studies. In the present study, we aimed to review the radiomitigative and radioprotective effects of selenium on normal cells/tissues, as well as its radiosensitive effect on cancer cells.  相似文献   
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Cardiovascular diseases are the main cause of death globally. Many attempts have been done to ameliorate the pathological changes after the occurrence of myocardial infarction. Curcumin is touted as a polyphenol phytocompound with appropriate cardioprotective properties. In this study, the therapeutic effect of curcumin was investigated on acute myocardial infarction in the model of rats. Rats were classified into four groups; control, isoproterenol hydrochloride (ISO) (100 mg/kbw), curcumin (50 mg/kbw), and curcumin plus ISO treatment groups. After 9-day administration of curcumin, levels of lactate dehydrogenase (LDH), creatine kinase (CK), and cardiac troponin I (cTnI) were determined. Superoxide dismutase (SOD) and malondialdehyde (MDA) contents were measured to investigate the oxidative status in infarct rats received curcumin. By using H & E staining, tissue inflammation was performed. Masson’s trichrome staining was conducted to show cardiac remodeling and collagen deposition. The number of apoptotic cells was determined by using the terminal deoxynucleotidyl transferase dUTP nick end labeling assay. Data showed the serum decrease of LDH, CK, and cTnI in infarct rats after curcumin intake compared to the rats given (ISO) ( P < 0.05). Curcumin was found to reduce oxidative status by reducing SOD and MDA contents ( P < 0.05). Gross and microscopic examinations revealed that the decrease of infarct area, inflammation response and collagen deposition in rats given ISO plus curcumin ( P < 0.05). We noted the superior effect of curcumin to reduce the number of apoptotic cardiomyocytes after 9 days. Data point the cardioprotective effect of curcumin to diminish the complication of infarction by the reduction of cell necrosis and apoptosis in a rat model of experimental infarction.  相似文献   
67.
The koala's Phascolarctos cinereus distribution is currently restricted to eastern and south‐eastern Australia. However, fossil records dating from 70 ± 4 ka (ka = 103 yr) from south‐western Australia and the Nullarbor Plain are evidence of subpopulation extinctions in the southwest at least after the Last Interglacial (~128–116 ka). We hypothesize that koala sub‐population extinctions resulted from the eastward retraction of the koala's main browse species in response to unsuitable climatic conditions. We further posit a general reduction in the distribution of main koala‐browse trees in the near future in response climate change. We modelled 60 koala‐browse species and constructed a set of correlative species distribution models for five time periods: Last Interglacial (~128–116 ka), Last Glacial Maximum (~23–19 ka), Mid‐Holocene (~7–5 ka), present (interpolations of observed data, representative of 1960–1990), and 2070. We based our projections on five hindcasts and one forecast of climatic variables extracted from WorldClim based on two general circulation models (considering the most pessimistic scenario of high greenhouse‐gas emissions) and topsoil clay fraction. We used 17 dates of koala fossil specimens identified as reliable from 70 (± 4) to 535 (± 49) ka, with the last appearance of koalas at 70 ka in the southwest. The main simulated koala‐browse species were at their greatest modelled extent of suitability during the Last Glacial Maximum, with the greatest loss of koala habitat occurring between the Mid‐Holocene and the present. We predict a similar habitat loss between the present and 2070. The spatial patterns of habitat change support our hypothesis that koala extinctions in the southwest, Nullarbor Plain and central South Australia resulted from the eastward retraction of the dominant koala‐browse species in response to long‐term climate changes. Future climate patterns will likely increase the extinction risk of koalas in their remaining eastern ranges.  相似文献   
68.
Brassica napus (oilseed rape, canola) seedling resistance to Leptosphaeria maculans, the causal agent of blackleg (stem canker) disease, follows a gene‐for‐gene relationship. The avirulence genes AvrLmS and AvrLep2 were described to be perceived by the resistance genes RlmS and LepR2, respectively, present in B. napus ‘Surpass 400’. Here we report cloning of AvrLmS and AvrLep2 using two independent methods. AvrLmS was cloned using combined in vitro crossing between avirulent and virulent isolates with sequencing of DNA bulks from avirulent or virulent progeny (bulked segregant sequencing). AvrLep2 was cloned using a biparental cross of avirulent and virulent L. maculans isolates and a classical map‐based cloning approach. Taking these two approaches independently, we found that AvrLmS and AvrLep2 are the same gene. Complementation of virulent isolates with this gene confirmed its role in inducing resistance on Surpass 400, Topas‐LepR2, and an RlmS‐line. The gene, renamed AvrLmS‐Lep2, encodes a small cysteine‐rich protein of unknown function with an N‐terminal secretory signal peptide, which is a common feature of the majority of effectors from extracellular fungal plant pathogens. The AvrLmS‐Lep2/LepR2 interaction phenotype was found to vary from a typical hypersensitive response through intermediate resistance sometimes towards susceptibility, depending on the inoculation conditions. AvrLmS‐Lep2 was nevertheless sufficient to significantly slow the systemic growth of the pathogen and reduce the stem lesion size on plant genotypes with LepR2, indicating the potential efficiency of this resistance to control the disease in the field.  相似文献   
69.
Reconstitution of the T cell repertoire after allogeneic stem cell transplantation is a long and often incomplete process. As a result, reactivation of Epstein-Barr virus (EBV) is a frequent complication that may be treated by adoptive transfer of donor-derived EBV-specific T cells. We generated donor-derived EBV-specific T cells by stimulation with peptides representing defined epitopes covering multiple HLA restrictions. T cells were adoptively transferred to a patient who had developed persisting high titers of EBV after allogeneic stem cell transplantation for angioimmunoblastic T-cell lymphoma (AITL). T cell receptor beta (TCRβ) deep sequencing showed that the T cell repertoire of the patient early after transplantation (day 60) was strongly reduced and only very low numbers of EBV-specific T cells were detectable. Manufacturing and in vitro expansion of donor-derived EBV-specific T cells resulted in enrichment of EBV epitope-specific, HLA-restricted T cells. Monitoring of T cell clonotypes at a molecular level after adoptive transfer revealed that the dominant TCR sequences from peptide-stimulated T cells persisted long-term and established an EBV-specific TCR clonotype repertoire in the host, with many of the EBV-specific TCRs present in the donor. This reconstituted repertoire was associated with immunological control of EBV and with lack of further AITL relapse.  相似文献   
70.
Genome size variation in plants is thought to be correlatedwith cytological, physiological, or ecological characters. However,conclusions drawn in several studies were often contradictory.To analyze nuclear genome size evolution in a phylogenetic framework,DNA contents of 134 accessions, representing all but one speciesof the barley genus Hordeum L., were measured by flow cytometry.The 2C DNA contents were in a range from 6.85 to 10.67 pg indiploids (2n = 14) and reached up to 29.85 pg in hexaploid species(2n = 42). The smallest genomes were found in taxa from theNew World, which became secondarily annual, whereas the largestdiploid genomes occur in Eurasian annuals. Genome sizes of polyploidtaxa equaled mostly the added sizes of their proposed progenitorsor were slightly (1% to 5%) smaller. The analysis of ancestralgenome sizes on the base of the phylogeny of the genus revealedlineages with decreasing and with increasing genome sizes. Correlationsof intraspecific genome size variation with the length of vegetationperiod were found in H. marinum populations from Western Europebut were not significant within two species from South America.On a higher taxonomical level (i.e., for species groups or theentire genus), environmental correlations were absent. Thiscould mostly be attributed to the superimposition of life-formchanges and phylogenetic constraints, which conceal ecogeographicalcorrelations.  相似文献   
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