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The safety and potential efficacy of FK506 in combination with a short course of methotrexate (MTX) for the prevention of acute graft-versus- host disease (GVHD) after marrow transplantation from HLA-matched unrelated donors was evaluated in a single-arm Phase II study conducted at two centers. Forty-three patients, 15 to 54 (median 41) years of age, were transplanted for hematologic malignancies. Thirty-seven of 43 evaluable patients had evidence of sustained marrow engraftment. Five patients died before day 17 after transplantation. The median time to an absolute neutrophil count of > 0.5 x 10(5)/L was 21 (range, 14 to 30) days. Nephrotoxicity (serum creatinine concentration > 2 mg/dL or doubling of baseline) occurred in 32 patients (74% cumulative incidence during the first 100 days after transplant). Other adverse effects included hypertension (n = 27), hyperglycemia (n = 27), neurotoxicity (n = 9) and thrombotic thrombocytopenic purpura (n = 2). Severe veno- occlusive disease of the liver occurred in 9 (21%) of the 43 patients. Eighteen patients (42%) developed grades II to IV acute GVHD and five (12%) developed grades III to IV acute GVHD. Twelve of 25 evaluable patients developed extensive chronic GVHD within 1 year of marrow transplantation resulting in an estimate of the probability of developing this complication of 48%. The cumulative incidence of transplant-related mortality during the first 100 days was 37%. Kaplan- Meier estimates of disease-free survival at 2 years for good-risk, poor- risk, and all patients were 65%, 4%, and 32%, respectively. FK506 in combination with a short course of MTX appears active in preventing acute GVHD after marrow transplantation from unrelated donors. Further studies comparing the combination of FK506 and MTX with cyclosporine and MTX for the prevention of acute GVHD are warranted.  相似文献   
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Human Toll‐like receptors (TLRs) TLR7, TLR8, and TLR9 are important immune sensors of foreign nucleic acids encountered by phagocytes. Although there is growing evidence implicating TLR7 and TLR9 in the detection of intracellular pathogenic bacteria, characterization of such a role for TLR8 is currently lacking. A recent genetic study has correlated the presence of a TLR8 single nucleotide polymorphism (SNP) (rs3764880:A>G; p.Met1Val) with the development of active tuberculosis, suggesting a role for TLR8 in the detection of phagosomal bacteria. Here we provide the first direct evidence that TLR8 sensing is activated in human monocytic cells following Helicobacter pylori phagocytosis. In addition, we show that rs3764880 fine tunes translation of the two TLR8 main isoforms, without affecting protein function. Although we show that TLR8 variant 2 (TLR8v2) is the prevalent form of TLR8 contributing to TLR8 function, we also uncover a role for the TLR8 long isoform (TLR8v1) in the positive regulation of TLR8 function in CD16+CD14+ differentiated monocytes. Thus, TLR8 sensing can be activated following bacterial phagocytosis, and rs3764880 may play a role in the modulation of TLR8‐dependent microbicidal response of infected macrophages. Hum Mutat 31:1069–1079, 2010. © 2010 Wiley‐Liss, Inc.  相似文献   
96.
Ductal carcinoma in situ (DCIS) is a group of heterogeneous lesions genetically, morphologically, and biologically. Recently, breast epithelium in the terminal ductal lobular unit has been sub-classified based on the expression of several cytokeratin markers as stem cells (CK5/6 +), luminal cells (CK8, CK18 +), and basal cells (CK14, CK17 +). In this study we describe the relationship between DCIS of different nuclear grades (non-high grade and high grade) and these cell origin markers. Fifty-three cases of non-high grade and 46 cases of high grade DCIS were selected, and representative sections from each case were stained with antibodies to these cytokeratin markers. High grade DCIS showed significantly higher rates of expression with stem and basal cell markers compared with non-high grade DCIS (p <0.05). The majority of DCIS, both high grade and non-high grade, expressed luminal cell markers (67% to 91%) and single type of cell origin marker (72% to 87%). High-grade DCIS more frequently co-expressed all three types of cell origin markers compared with non-high grade DCIS (p <0.05). In summary, a subset of high grade DCIS frequently rises from stem or/and basal cell populations; the subset is associated with poor prognosis in invasive breast carcinoma. Thus, these markers may be used to identify a potentially more aggressive subgroup of breast carcinoma at its pre-invasive stage (DCIS), and to manage it accordingly. Second, most DCIS express luminal cell markers, suggesting that malignant transformation occurs relatively late along the cell differentiation pathway, contrary to the traditional belief that most neoplasms arise from a more primitive stem cell population. Third, the majority of DCIS exclusively express one type of progenitor marker, indicating that in most incidences they may arise from a single progenitor population. Last, triple expression of all types of cell origin marker is frequently associated with high grade DCIS, suggesting that more complicated pathways are involved in these more aggressive lesions. Further studies are needed to delineate the relationships of cell origin markers in DCIS and invasive carcinoma to the clinical outcome.  相似文献   
97.
We have previously reported that high grade and non-high grade ductal carcinoma in situ (DCIS) of the breast can be subdivided into 3 cell origin subtypes (luminal, basal/stem, and null), and that high grade DCIS is more frequently associated with basal/stem cell subtypes compared to non-high grade DCIS. Here we refine the relationships between these 3 subtypes and the expression patterns of estrogen receptor-alpha (ER-alpha), progesterone receptor (PR), HER-2/neu, and epidermal growth factor receptor (ERFR) in 53 cases of non-high grade and 46 cases of high nuclear grade DCIS. Using a panel of antibodies to ER-alpha, PR, HER-2/neu, and EGFR, along with cytokeratin (CK) markers (CK5/6, CK8, CK14, CK17, and CK18), we found that all 3 cell origin subtypes can express ER-alpha and PR, and their expression is higher in non-high grade DCIS than in high grade DCIS; the expression of HER-2/neu is associated with luminal subtype only in non-high grade DCIS, but can be seen in all 3 subtypes in high grade DCIS; the expression of EGFR is low and is present only in luminal cell subtypes in both high and non-high grade DCIS. Basal/ stem cell and null cell subtypes occur in younger patients in non-high grade DCIS compared to high grade DCIS. In conclusion, the expression patterns of ER-alpha, PR, HER-2/neu, and EGFR are markedly different in different cell origin subtypes of both high grade and non-high grade DCIS, suggesting that cell origin subtypes as well as nuclear grade contribute to the biological and molecular heterogeneity of DCIS.  相似文献   
98.
This is the second report of the United Kingdom Primary Immunodeficiency (UKPID) registry. The registry will be a decade old in 2018 and, as of August 2017, had recruited 4758 patients encompassing 97% of immunology centres within the United Kingdom. This represents a doubling of recruitment into the registry since we reported on 2229 patients included in our first report of 2013. Minimum PID prevalence in the United Kingdom is currently 5·90/100 000 and an average incidence of PID between 1980 and 2000 of 7·6 cases per 100 000 UK live births. Data are presented on the frequency of diseases recorded, disease prevalence, diagnostic delay and treatment modality, including haematopoietic stem cell transplantation (HSCT) and gene therapy. The registry provides valuable information to clinicians, researchers, service commissioners and industry alike on PID within the United Kingdom, which may not otherwise be available without the existence of a well‐established registry.  相似文献   
99.
Models of ischemic brain injury in the nonhuman primate (NHP) are advantageous for investigating mechanisms of central nervous system (CNS) injuries and testing of new therapeutic strategies. However, issues of reproducibility and survivability persist in NHP models of CNS injuries. Furthermore, there are currently no pediatric NHP models of ischemic brain injury. Therefore, we have developed a NHP model of cortical focal ischemia that is highly reproducible throughout life to enable better understanding of downstream consequences of injury. Posterior cerebral arterial occlusion was induced through intracortical injections of endothelin‐1 in adult (n = 5) and neonatal (n = 3) marmosets, followed by magnetic resonance imaging (MRI), histology and immunohistochemistry. MRI revealed tissue hyperintensity at the lesion site at 1–7 days followed by isointensity at 14–21 days. Peripheral macrophage and serum albumin infiltration was detected at 1 day, persisting at 21 days. The proportional loss of total V1 as a result of infarction was consistent in adults and neonates. Minor hemorrhagic transformation was detected at 21 days at the lesion core, while neovascularization was detected in neonates, but not in adults. We have developed a highly reproducible and survivable model of focal ischemia in the adult and neonatal marmoset primary visual cortex, demonstrating similar downstream anatomical and cellular pathology to those observed in post‐ischemic humans.  相似文献   
100.
ObjectiveTo investigate the potentials of the root bark of Annona (A.) senegalensis in the control of seizure and related hypnotic and motor incoordination effects in mice using experimental models.MethodsThe methanol extract (ME) of the root bark of A. senegalensis was studied in mice using pentylenetetrazole (PTZ) induced convulsions, phenobarbitone induced sleeping time and motor coordination test on rota-rod performance. Acute toxicity and lethality (LD50) test as well as phytochemical analysis were also carried out.ResultsThe extract (200, 400, 800 mg/kg) exhibited a non-dose dependent significant (P <0.05) delay in the onset of both tonic and clonic phases of seizure induced by PTZ (60 mg/kg, s.c.) as well as offered a 100% protection (200 mg/kg) in mice from PTZ induced seizures. The extract significantly (P <0.05) decreased the latency and increased the duration of phenobarbitone induced sleeping time. At 200 mg/kg, the extract exhibited a significant (P <0.05) motor incoordination. The acute toxicity test revealed an oral LD50 of 1 296 mg/kg, while the phytochemical studies showed the presence of alkaloids, resins, glycosides, carbohydrate, reducing sugar, flavonoids, terpenoids, saponins and tannins.ConclusionThe extract of A. senegalensis possessed anticonvulsant activity with pronounced hypnotic and muscle relaxant effects.  相似文献   
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