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1.
Patients with fever and granulocytopenia are at risk of developing severe infection. We performed a prospective, randomized trial to evaluate the efficacy of low-dose cefepime plus amikacin (C-A) compared to low-dose piperacillin/tazobactam plus amikacin (PT-A). Patients received cefepime (2 g/12 h) plus amikacin (15 mg/kg/day) or piperacillin/tazobactam (4 g/500 mg/8 h) plus amikacin. A total of 317 episodes of febrile granulocytopenia in 190 patients were studied (152 in the C-A group, 165 in the PT-A group). A microbiologically documented infection was present in 53 (35%) episodes in the C-A group and 41 (25%) episodes in the PT-A group (p = ns); a clinically documented infection was observed in 39 (26%) and 47 (28%) episodes, respectively. Toxicity was observed in 6 (4%) episodes in the C-A group and in 5 (3%) episodes in the PT-A group. The antibiotic success rate (no change or addition of antibiotics) was recorded in 89 (59%) and 105 (64%) cases, respectively (p = ns). Mortality related to infection was similar in each arm (3.9% vs. 3.6%). Combination therapy of low-dose β-lactam with an aminoglycoside achieves very good response rates and low rates of toxicity. It might be an attractive option in an environment of increasing resistance among gram-negative bacteria.  相似文献   

2.
1.  hsp of bacteria are important immunogens.
2.  The immune response to bacterial hsp include clones of T cells which may recognize self antigens and, therefore, could lead to autoimmunity. This response could be regulated by the genetic make-up (HLA-DR association) or environmental exposure (exposure to cross-reacting bacterial antigens) or both. In this regard the putative association of bacterial colonization with rejection following allogeneic bone marrow transplantation [33] is analogous to the allogeneic response induced by virus exposure [8]. Both of these phenomena could be the result of an exposure which stimulates T cell clones with alloreactivity. Such examples added to those cited above may represent foreign bacterial antigens eliciting an antiself response.
3.  The mapping of hsp to the MHC and the role of hsp in antigen binding and presentation is intriguing both from a standpoint of a possible role in cell regulation and in association with disease susceptibility. If the presence of a disease is linked to a given hsp allele (as appears to be the case with juvenile diabetes), this could occur because (1) the hsp is involved in presentation of a foreign antigen which stimulates a cross-reactive T cell clone, (2) the hsp allele is recognized by a T cell population which is expanded by an particular bacterial cross-reactive antigen, or (3) the hsp allele affects the magnitude of the immune response by itself presenting the antigen (analogous to HLA-DR) or through some other ill-defined mechanism.
  相似文献   

3.
《HIV clinical trials》2013,14(6):418-427
Abstract

Darunavir is a new protease inhibitor (PI) with in vitro activity against wild-type and PI-resistant HIV; it is used with the pharmacokinetic booster ritonavir. The currently approved dose of darunavir/ritonavir is 600/100 mg twice-daily, licensed for treatment-experienced patients. However, during the clinical development of darunavir, a range of once-daily and twice-daily doses of darunavir/ritonavir were evaluated. The relatively long terminal elimination plasma half-life of darunavir (15 hours) supports once-daily dosing. In treatment-naïve patients, the ARTEMIS trial has shown high rates of HIV RNA suppression for darunavir-ritonavir at the 800/100 mg once-daily dose (84% with HIV RNA <50 copies/mL at Week 48) versus a control arm of lopinavir/ritonavir (78% with HIV RNA <50 copies/mL). In a population pharmacokinetic substudy, darunavir 24-hour minimum plasma concentration levels remained above the predefined EC50 of 55 ng/mL for all 335 patients evaluated in the ARTEMIS trial. Once-daily darunavir/ritonavir has also been evaluated in treatment-experienced patients in the TMC114-C207 proof-of-principle trial and the POWER 1 and 2 trials. For the overall POWER trial population, with significant baseline resistance to PIs, the rates of HIV RNA suppression <50 copies/mL at Week 24 for darunavir/ritonavir 800/100 mg once-daily were lower than for the 600/100 mg twice-daily dosage (31% vs. 47%, respectively). However, for patients with no genotypic darunavir resistance-associated mutations at baseline, rates of HIV RNA suppression were 62% and 67% for the 800/100 mg once-daily and 600/100 mg twice-daily doses. The current evidence from clinical trials of darunavir/ritonavir supports the efficacy of the 800/100 mg once-daily dose for treatment-naïve patients and further evaluation for treatment-experienced patients with no genotypic resistance to darunavir.  相似文献   

4.
Two half brothers (maternally related) had a similar syndrome of microhydrocephaly in both brothers and dilatation of the spinal canal with fusion of thalami in one brother. Primordial growth delay was noted in both brothers, with severe mental retardation in the surviving brother. Both had ectodermal dysplasia with scaling, hyperkeratosis, and generalized alopecia, but normal sweat and sebaceous glands. Skeletal anomalies included hemivertebrae with abnormal segmentation in one and scoliosis with polydactyly in the other. Ears were apparently low set, large, and protruding, with mixed hearing loss in the brother who survived. Eye anomalies included maldevelopment of one eye in Patient 1 and small optic nerves more noticeable on one side in Patient 2. Both had cryptorchidism and dysplastic/hypoplastic kidneys of varying severity that resulted in the early postnatal death of one sib. Manifestations present in only one or the other sib included submucous cleft palate, aganglionosis of the rectum and colon, agenesis of one testicle, and single umbilical artery. This syndrome has not been described previously and may be due to an X-linked mutation. The acronym BRESEK reflects the common findings, whereas BRESHECK denotes all manifestations of both patients: brain, retardation, ectodermal dysplasia, skeletal deformities, Hirschsprung disease, ear/eye anomalies, cleft palate/cryptorchidism, and kidney dysplasia/hypoplasia. In addition to an X-linked mutation, a contiguous gene deletion or maternal mosaicism of an autosomal dominant gene must be considered. Am. J. Med. Genet. 68:386–390, 1997. © 1997 Wiley-Liss, Inc.  相似文献   

5.
Cytotoxic cells include natural killer (NK) cells and cytotoxic αβ and γδ T lymphocytes (CTLs). These cells express cytotoxic molecules of T-cell restricted intracellular antigen(TIA-1), and activated cytotoxic molecules of perforin, granzyme B, and FasL. Recent studies suggest that most extranodal T-cell lymphomas are derived from CTLs, and that NK cell lymphomas are extranodal. However, only a few nodal NK and cytotoxic lymphomas have been described so far. We present here the clinicopathological features of seven cases of nodal cytotoxic T and NK cell lymphomas. The study excluded anaplastic large-cell lymphomas expressing cytotoxic molecules. The neoplastic cells of all cases contained activated cytotoxic molecules of TIA-1, granzyme B, Fas ligand, and/or perforin. Phenotypically and genotypically, four cases showed αβ T cell type [CD2+, CD3+, T-cell receptor (TCR) δ-1–, βF1+, and TCR gene rearrangement], two cases showed γδ T-cell type [CD2+, CD3+, T-cell receptor (TCR)δ–1+, βF1–, and TCR gene rearrangement], and one case showed NK cell type [CD2+, CD3-, CD56+, T-cell receptor (TCR)δ-1–, βF1–, and TCR gene germline]. Using Southern blot analysis, Epstein-Barr virus (EBV) sequences were detected in six cases, and monoclonal terminal repeat proliferation was confirmed. In addition, in situ hybridization (ISH) studies for EBV showed EBV infection in almost all neoplastic cells. Clinically, all patients presented with peripheral lymphadenopathy in high clinical stages and showed an aggressive course. Hepatosplenomegaly was detected in six cases. During the course of the disease, bone marrow and extranodal invasion were noted in five cases. The nodal type showed an aggressive clinical course in all cases but one, as did the extranodal type. The nodal type varied in phenotype, but was closely associated with EBV infection.  相似文献   

6.
《Immunology today》1996,17(2):92-97
Diversification strategies for immunoglobulins vary widely in different species. Here, Jean-Claude Weill and Claude-Agnès Reynaud argue that V(D)J recombination arose as a means for achieving allelic exclusion rather than diversity, and postulate that the choice of a diversification strategy is selected along with a specific site of B-cell differentiation. They propose that somatic mutation and gene conversion represent analogous molecular strategies occurring in specific chromatin accessibility contexts.  相似文献   

7.
8.
Due to their minority among the non-Hodgkin lymphomas, classification of extranodal T-cell lymphomas, including those of the natural killer (NK) cell type, has long been controversial and unclear, and the clinical outcome is not well clarified. Recently, new well-defined disease entities have been described based on tumor cell biology combined with anatomical site, clinical features, Epstein-Barr virus (EBV) status, and cell lineage as determined by immunophenotype and genotype. Cytological features are usually not specific, and there are no morphologic correlates with the classification of extranodal T/NK-cell lymphomas. From a human T-cell lymphotropic virus type 1 (HTLV-1) endemic area in Japan, we report here the analysis of 144 cases of extranodal T-cell lymphoma, from which fresh tissues were available. As the clinicopathological features were known, we simply reclassified the cases according to cell lineage and anatomical site. The extranodal T-cell lymphomas were classified into three types on the basis of cell lineage: (1) natural killer cell (NK) type [sCD3-, CD56+, T-cell receptor gene (TCR) germline], (2) cytotoxic T lymphocyte (CTL) type [sCD3+, TIA-1+, TCR rearranged, CD8+/-, CD4-/+], and (3) non-NK/CTL type [sCD3+, TIA-1-, TCR rearranged, CD4+/-, CD8-/+]. In addition to cell lineage, the anatomical site and clinical features were added for subclassification. NK type tumors (35 cases) included the lymphoblastic type, nasal/nasal-type NK lymphoma, and NK leukemia. The CTL type (46 cases) included anaplastic large cell lymphoma (ALCL), cutaneous type, intestinal, gamma delta T-cell type, and an unspecified type. The non-NK/CTL type (63 cases) included adult T-cell leukemia/lymphoma (ATLL), mycosis fungoides (MF), and an unspecified type. With the exception of ATLL and MF, most extranodal T-cell lymphomas had a cytotoxic phenotype of NK type or CTL type and were often associated with EBV infection. MF and the unspecified type within the non-NK/CTL tumors, with the exception of ATLL, had a favorable prognosis. However, NK and CTL types, with the exception of ALCL, were associated with a poor prognosis. Our results indicate that anatomical site and cell lineage are useful predictors of clinical outcomes of extranodal T-cell lymphomas.  相似文献   

9.

Background

Hereditary non-polyposis colorectal cancer comprises Lynch syndrome and familial colorectal cancer type X (FCCTX). Differences in genetics, demographics and histopathology have been extensively studied. The purpose of this study is to characterize their immunoprofile of markers other than MMR proteins.

Methods

We compared the expression patterns of cytokeratins (CK7 and CK20), mucins (MUC2/5 AC/6), CDX2 and β-catenin in Lynch syndrome and FCCTX.

Results

Differences were identified for CK20 and nuclear β-catenin, which were significantly more often expressed in FCCTX than in Lynch syndrome (p < 0.001), whereas MUC2, MUC5AC and MUC6 were overexpressed in Lynch syndrome tumors compared with FCCTX tumors (p = 0.001, <?0.01, and <?0.001, respectively). We observed no differences in the expression patterns of CK7 and CDX2.

Conclusions

In summary, we identified significant differences in the immunoprofiles of colorectal cancers linked to FCCTX and Lynch syndrome with a more sporadic-like profile in the former group and a more distinct profile with frequent MUC6 positivity in the latter group.
  相似文献   

10.
Triglyceride-rich lipoproteins contain both apolipoproteins E (ApoE) and C-III (ApoC-III), which show opposite functional properties. The relationships between the ApoE (ε2/ε3/ε4) gene polymorphism and ApoC-III/ApoE ratio has never been investigated. A large population (n=552) of cardiovascular patients, without diabetes and/or lipid-lowering therapy, with or without metabolic syndrome (MetSyn), was genotyped for ε2/ε3/ε4 polymorphism and their ApoCIII/ApoE ratio was evaluated. A second group of patients (n=76) with peripheral artery disease was also genotyped and their ApoC-III/ApoE ratios were measured in HDL and non-HDL fractions. Subjects with E2 had higher and E4 carriers lower TG,ApoE and ApoC-III levels, respectively. The ApoCIII/ ApoE ratio showed an opposite trend, gradually increasing from E2/E2 to E4/E4 subjects. MetSyn patients also had an elevated ApoC-III/ApoE ratio and E4 carriers were more frequent in MetSyn patients (OR 2.08 with a 95%CI 1.22–3.5). The distribution of ApoC-III/ApoE ratio was confirmed also in the second group, with lower values in E2/E3 and higher in E3/E4 subjects. Similar results were obtained for the concentrations measured in non-HDL fractions, but not in the HDL fractions. ApoE ε2/ε/ε4 gene polymorphism is a determinant of the relative proportion of apolipoprotein C-III to E. Carriers of the unfavourable E4 allele present the highest ApoCIII/ApoE ratio and are twofold more frequent among individuals affected by MetSyn. These authors contributed equally to the work  相似文献   

11.
Tesaglitazar was developed as a dual peroxisome proliferator-activated receptor (PPARα/γ). To support the clinical program, a hamster carcinogenicity study was performed. The only neoplastic findings possibly related to treatment with tesaglitazar were low incidences of hemangioma and hemangiosarcoma in the liver of male animals. A high-power, two-year investigative study with interim necropsies was performed to further elucidate these findings. Treatment with tesaglitazar resulted in changes typical for exaggerated PPARα pharmacology in rodents, such as hepatocellular hypertrophy and hepatocellular carcinoma, but not an increased frequency of hemangiosarcomas. At the highest dose level, there was an increased incidence of sinusoidal dilatation and hemangiomas. No increased endothelial cell (EC) proliferation was detected in vivo, which was confirmed by in vitro administration to ECs. Immunohistochemistry and gene expression analyses indicated increased cellular stress and vascular endothelial growth factor (VEGF) expression in the liver, which may have contributed to the sinusoidal dilatation. A two-fold increase in the level of circulating VEGF was detected in the hamster at all dose levels, whereas no effect on VEGF was observed in patients treated with tesaglitazar. In conclusion, investigations have demonstrated that tesaglitazar does not produce hemangiosarcomas in hamster despite a slight effect on vascular morphology in the liver.  相似文献   

12.
This work describes the preparation of magnetic and pH-sensitive beads based on κ-carrageenan and sodium alginate for use as drug-targeting carriers. Physical cross-linking using K+/Ca2+ ions was applied to obtain ionic cross-linked magnetic hydrogel beads. The produced magnetite beads were thoroughly characterized by TEM, SEM/EDS, XRD, FTIR, and VSM techniques. While the water absorbency (WA) of magnetic beads was enhanced by increasing the weight ratio of κ-carrageenan, introducing magnetic nanoparticles caused a decrease in WA capacity from 15.4 to 6.3 g/g. Investigation on the swelling of the hydrogel beads in NaCl, KCl, and CaCl2 solutions revealed the disintegration of beads depending on the composition of hydrogel beads and the type of metal cations in swelling media. The swelling ratio of beads indicated pH-dependent properties with maximum water absorbing at pH 7.4. Also, it was found that the strength of pH-sensitivity of magnetic beads was low for beads with the high content of carrageenan component. The in vitro drug release studies from hydrogels exhibited significant behaviors on the subject of physiological-simulated pH values and external magnetic fields. The maximum cumulative releases obtained were 98 and 43% at pH values 7.4 and 1.2, respectively. The Introducing magnetite nanoparticles influenced the cumulative release of drug.  相似文献   

13.
Multifunctional and water-soluble superparamagnetic iron oxide (SPIO) nanocarriers were developed for targeted drug delivery and positron emission tomography/magnetic resonance imaging (PET/MRI) dual-modality imaging of tumors with integrin α(v)β? expression. An anticancer drug was conjugated onto the PEGylated SPIO nanocarriers via pH-sensitive bonds. Tumor-targeting ligands, cyclo(Arg-Gly-Asp-d-Phe-Cys) (c(RGDfC)) peptides, and PET ??Cu chelators, macrocyclic 1,4,7-triazacyclononane-N, N', N″-triacetic acid (NOTA), were conjugated onto the distal ends of the PEG arms. The effectiveness of the SPIO nanocarriers as an MRI contrast agent was evaluated via an in vitro r? MRI relaxivity measurement. cRGD-conjugated SPIO nanocarriers exhibited a higher level of cellular uptake than cRGD-free ones in vitro. Moreover, cRGD-conjugated SPIO nanocarriers showed a much higher level of tumor accumulation than cRGD-free ones according to non-invasive and quantitative PET imaging, and ex vivo biodistribution studies. Thus, these SPIO nanocarriers demonstrated promising properties for combined targeted anticancer drug delivery and PET/MRI dual-modality imaging of tumors.  相似文献   

14.

Introduction

The current study aims to explore the knowledge, attitude, and perception of hospital pharmacists towards HIV/AIDS and patients living with HIV/AIDS (PLWHA) in the state of Kedah, Malaysia.

Material and methods

This was a cross-sectional study conducted among the hospital pharmacists in three government hospitals in Kedah, using a self-administered 43-item questionnaire. Data analysis was done using non-parametric and multinomial regression.

Results

A total of 75 respondents participated in this study, resulting in a response rate of 60.8%. The majority were found to be well aware of the causes of HIV/AIDS. However, about 34 (45.3%) believed erroneously that HIV/AIDS cannot be transmitted through tattooing or body piercing. Nearly 25 (33.3%) of the respondents believed that preventing the use of intravenous drugs may not be effective to prevent HIV/AIDS and endorsed social isolation as a measure to prevent HIV/AIDS. The majority (66.6%) had negative attitudes and about 20% held extremely negative attitudes. Findings from regression modelling revealed that hospital (–2 log likelihood = 215.182, χ2 = 18.060, Df = 8, p = 0.021) and gender (–2 log likelihood = 213.643, χ2 = 16.521, Df = 8, p = 0.035) were more likely to affect the attitudes of respondents.

Conclusions

Overall, more than one third of the respondents were found to have negative attitudes towards PLWHA. Gender, job experience, and hospitals with more HIV/AIDS patient visits were the main factors affecting attitudes.  相似文献   

15.
16.
患儿 男,42天.体重5.6 kg,身长56.5 cm,头围38.5 cm,胸围39.5 cm,前囟1.0×1.0cm,心前区可闻及Ⅱ/6级杂音,小儿智能发育检查诊断:智力发展指数88(中下),运动发展指数85(中下).其母在孕16+2周时在本院做产前血清学唐氏综合征筛查,风险值为1:180,属唐氏综合征高风险.拒绝产前诊断.产后42天体检外周血细胞培养及染色体核型分析结果为:48,XYYY[42]/47,XYY[45]/46XY[3]/45,X[10].其父母拒绝为其做进一步的追踪检查.其父母染色体核型未检测.  相似文献   

17.
ObjectivesWe aimed to evaluate the effect of ampC derepression on the cefepime MIC in different species of Enterobacterales with chromosomally encoded inducible AmpC β-lactamase.MethodsWe analysed a large number of wild-type/mutant pairs (n = 1030 in total). Cefepime MICs were determined by broth microdilution according to EUCAST recommendations.ResultsampC derepression led to increases in MIC by up to 10 dilutions, and significant increases by > 2 MIC dilutions were common across species (744/1030 mutants (72.2%) in total). Interestingly, the frequency of cefepime S→I/S→R transitions varied considerably between species: 66.3% in Enterobacter cloacae complex (167/252 mutants), 1.1% in Klebsiella aerogenes (2/180 mutants), 18.1% in Citrobacter freundii complex (50/277 mutants), 36.4% in Hafnia alvei (59/162 mutants), 19.0% in Providencia rettgeri (4/21 mutants), 22.9% in Providencia stuartii (11/48 mutants), 12.3% in Serratia marcescens (7/57 mutants), 20.0% in Serratia liquefaciens (6/30 mutants) and 0% in Morganella morganii (0/3 mutants).ConclusionsOur data show that the cefepime MIC is often increased by ampC derepression. However, the risk of S→I/S→R transition is dependent on the species.  相似文献   

18.
19.
20.
《Genetics in medicine》2019,21(6):1355-1362
PurposeRacial minority populations are underrepresented in genomics research. This study enrolled African-descended individuals in a sequencing study and reported their characteristics.MethodsWe purposively recruited 467 individuals self-identified as African, African American, or Afro-Caribbean to the ClinSeq® study and surveyed them about knowledge, motivations, expectations, and traits. Summary statistics were calculated and compared with data from the study’s original cohort, which was primarily White and self-referred.ResultsRecruitment took five years and 83% of enrollees completed the survey. Participants had modest knowledge about benefits and limitations of sequencing (s = 5.1, ranges: 0–10), and less than the original cohort (= 7.5 and 7.7, respectively). Common motivations to enroll were learning information relevant to personal health (49%) or family members’ health (33%), and most had realistic expectations of sequencing. Like the original cohort, they had high levels of optimism, openness, and resilience.ConclusionEarly adopters may have relatively consistent personality traits irrespective of majority/minority status and recruitment methods, but high levels of genomics knowledge are not universal. Research should determine whether recruitment and consent procedures provide adequate education to promote informed choices and realistic expectations, which are vital to ethical research and increasing genomics research participation in underrepresented communities.  相似文献   

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