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排序方式: 共有372条查询结果,搜索用时 15 毫秒
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Polymerase chain reaction-sequence-specific primer (PCR-SSP) typing for human leukocyte antigen (HLA)-B in a male 25-year-old Caucasian individual of Iranian origin and in a 42-year-old German Caucasian bone marrow donor revealed reaction patterns that did not agree with any known HLA specificity, thus suggesting in both cases the existence of a novel allele. Sequence-based typing (SBT) after allelic separation revealed the sequences of the new alleles HLA-B*5611 and B*3546. The sequence patterns of both new alleles might have been generated as the results of double crossing over, possibly over several generations. During the analysis of the HLA-B*3546 intron 2 sequence for possible crossing over points, a base insert, an additional G after position 700, was found. This insert was analyzed using SBT and PCR-SSP and was found to be present not only in all samples carrying B*35, but also in all HLA-B specificities tested. It appears that all known HLA-B alleles may contain a G insert at position 700 of intron 2, and that the published intron 2 sequence alignments of the HLA-B locus may contain errors at this position. 相似文献
23.
Zindler E Gehrke N Luft C Reuter S Taube C Finotto S Reske-Kunz AB Sudowe S 《American journal of respiratory cell and molecular biology》2008,38(1):38-46
Particle-mediated epidermal delivery (PMED) of allergen genes efficiently prevents systemic sensitization and suppresses specific immunoglobulin E synthesis. We investigated in a mouse model of allergic airway disease the effect of PMED on the elicitation of local inflammatory reactions in the lung. BALB/c mice were biolistically transfected with plasmids encoding beta-galactosidase (betaGal) as model allergen under control of the DC-targeting fascin promoter and the ubiquitously active cytomegalovirus promoter, respectively. Mice were challenged intranasally with betaGal-protein with or without intermediate sensitization with betaGal adsorbed to aluminiumhydroxide. Subsequently, local cytokine production and recruitment of IFN-gamma-producing CD8(+) effector T cells into the airways were determined, and inflammatory parameters such as cellular infiltration in the bronchoalveolar lavage (BAL) and airway hyperresponsiveness (AHR) were measured. PMED of betaGal-encoding plasmids before sensitization significantly reduced frequencies of eosinophils in the BAL and shifted the local T helper (Th) cell response from a distinct Th2 response toward a Th1-biased response. However, AHR triggered by allergen challenge via the airways was not alleviated in vaccinated mice. Most important, we show that PMED using betaGal-encoding DNA without subsequent sensitization recruited Tc1 cells into the lung and caused a Th1-prone local immune response after subsequent intranasal provocation, accompanied by neutrophilic infiltration into the airways and elicitation of AHR. We conclude that robust Th1/Tc1 immune responses, although highly effective in the counter-regulation of local Th2-mediated pathology, might as well trigger local inflammatory reactions in the lung and provoke the induction of AHR in the mouse model of allergic airway disease. 相似文献
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Helena Moratin Agmal Scherzad Thomas Gehrke Pascal Ickrath Katrin Radeloff Norbert Kleinsasser Stephan Hackenberg 《Environmental and molecular mutagenesis》2018,59(3):247-259
The increasing usage of zinc oxide nanoparticles (ZnO‐NPs) in industrial applications as well as in consumer products raises concern regarding their potential adverse effects to a greater extend. Numerous studies have demonstrated toxic properties of NPs, however there is still a lack of knowledge concerning the underlying mechanisms. This study was designed to systematically investigate cytotoxicity, apoptosis, cell cycle alterations, and genotoxicity induced by ZnO‐NP. Moreover, it was an aim of the investigations to specify the diverse effects of nanoparticle exposure in malignant in comparison with non‐malignant cells. Therefore, human head and neck squamous cell carcinoma‐derived FaDu cells were incubated with 4–20 µg/ml of ZnO‐NPs for 1–48 hr and tested for cell viability, cell cycle alterations, apoptosis and caspase‐3 gene expression as a sensitive marker of molecular apoptotic processes with regard to time‐ and dose‐dependent effects. Human mesenchymal bone marrow stem cells were used as non‐malignant representatives to examine oxidative stress‐related genotoxicity. Results showed a significant reduction in cell viability as well as dose‐ and time‐dependent increase of apoptotic cells following nanoparticle treatment. Likewise, caspase‐3 gene expression enhanced already before first apoptotic cells were detectable. It could be observed that doses that were cytotoxic in tumor cells did not reduce viability in stem cells. However, the same concentrations already induced significant DNA damage. The findings of the study suggest to keep a more critical eye on the use of nanoparticles as anti‐cancer agents. Yet, additional in vivo studies are needed to assess safety concerns for consumers and patients. Environ. Mol. Mutagen. 59:247–259, 2018. © 2017 Wiley Periodicals, Inc. 相似文献
25.
Deena A. Rennerfeldt Amanda N. Renth Zsolt Talata Stevin H. Gehrke Michael S. Detamore 《Biomaterials》2013
Hydrogels are attractive for tissue engineering applications due to their incredible versatility, but they can be limited in cartilage tissue engineering applications due to inadequate mechanical performance. In an effort to address this limitation, our team previously reported the drastic improvement in the mechanical performance of interpenetrating networks (IPNs) of poly(ethylene glycol) diacrylate (PEG-DA) and agarose relative to pure PEG-DA and agarose networks. The goal of the current study was specifically to determine the relative importance of PEG-DA concentration, agarose concentration, and PEG-DA molecular weight in controlling mechanical performance, swelling characteristics, and network parameters. IPNs consistently had compressive and shear moduli greater than the additive sum of either single network when compared to pure PEG-DA gels with a similar PEG-DA content. IPNs withstood a maximum stress of up to 4.0 MPa in unconfined compression, with increased PEG-DA molecular weight being the greatest contributing factor to improved failure properties. However, aside from failure properties, PEG-DA concentration was the most influential factor for the large majority of properties. Increasing the agarose and PEG-DA concentrations as well as the PEG-DA molecular weight of agarose/PEG-DA IPNs and pure PEG-DA gels improved moduli and maximum stresses by as much as an order of magnitude or greater compared to pure PEG-DA gels in our previous studies. Although the viability of encapsulated chondrocytes was not significantly affected by IPN formulation, glycosaminoglycan (GAG) content was significantly influenced, with a 12-fold increase over a three-week period in gels with a lower PEG-DA concentration. These results suggest that mechanical performance of IPNs may be tuned with partial but not complete independence from biological performance of encapsulated cells. 相似文献
26.
Rauhut AS Gehrke BJ Phillips SB Bardo MT 《Pharmacology, biochemistry, and behavior》2002,73(3):611-622
In a series of experiments, the ability of selective mu- (beta-funaltrexamine, beta-FNA), delta- (naltrindole, nalt) and kappa- (nor-binaltorphimine, nor-BNI) opioid receptor antagonists to attenuate the unconditioned and conditioned hyperactive effects of morphine was examined. For comparison, the nonselective opioid receptor antagonist naloxone (nalx) was also examined. Locomotor activity served as the behavioral measure. Experiment 1 found that doses of 1 and 4, but not 16 mg/kg, of morphine effectively produced conditioned hyperactivity (CH). Experiments 2a-d found that beta-FNA, nalt, nor-BNI and nalx, respectively, attenuated unconditioned morphine-induced hyperactivity. Experiments 3a-c, however, found that none of the selective antagonists, given individually, attenuated CH. In contrast, nalx did attenuate CH (Experiment 3d). Collectively results suggest that the unconditioned and conditioned hyperactive responses to morphine are mediated by different receptor systems and that activation of multiple opioid-receptor subtypes mediate expression of CH. 相似文献
27.
OBJECTIVE: To study gender differences of coping with illness strategies in tension-type headaches. METHOD: We enrolled 89 subjects (50 women, 39 men) suffering from episodic (n = 37) and chronic (n = 52) tension-type headaches (TTH). Patients were required to answer a Freiburg Questionnaire of Coping with Illness (FQCI), a Von Zerssen Depression Scale (D-S), quality-of-life questionnaires, and a headache home diary (over 4 weeks). In addition, pressure pain thresholds (temporal muscles) and Total Tenderness Scores were obtained. RESULTS: While pain intensity, frequency and quality-of-life parameters were basically the same for female and male EPISODIC TTH sufferers, women scored significantly higher on the F3 subscale (distracting and encouraging) of the FQCI and tended to score higher on the F1 subscale (depressive). Among CHRONIC TTH patients, women reported the pain to be more intense (VAS), were more depressed (D-S), and scored lower on several quality-of-life scores. Female chronic TTH sufferers scored significantly lower on the F2 subscale (active coping) and tended to score higher on F5 (denying). CONCLUSIONS: We conclude that pessimistic coping with illness strategies are more frequent in female episodic and chronic TTH sufferers. We would like to recommend special psychologic intervention in particular to female chronic TTH sufferers which would offer counseling in developing active coping skills. 相似文献
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The levels for serum protein bound neutral carbohydrates (fucose, mannose, and galactose) were determined at specific intervals for 40 patients with small cell carcinoma of the lung and compared to the corresponding carcinoembryonic antigen (CEA) levels. In pretreatment samples, the frequency of elevation was 92.5% for fucose and 77.5% each for mannose and for galactose. CEA determined in these same samples was elevated (greater than 5 ng/ml) in 45.0%. One or more of the three carbohydrate levels were elevated in pretreatment serum of 95.0% of the patients. The individual frequency of elevation for each carbohydrate was significantly related to initial stage of disease (P less than 0.01). Median survival was significantly longer for patients based on a discriminant of less than 3 carbohydrates elevated in pretreatment samples (25 months) to all 3 elevated (11 months) with P = 0.0302. A single value, termed the biomarker index, was calculated to represent the summation of the individual carbohydrate levels per individual serum sample. The biomarker index was found to be directly correlated with extent of primary disease, number of metastic sites, tumor burden, and clinical response categories assessed at serial time points. For patients with both low Biomarker Index values and normal CEA levels in pretreatment samples, an initial rise in both determinations occurred frequently corresponding to partial or complete tumor response. The occurrence of such discordant results must be considered as a likely possibility for those patients with low or normal pretreatment biological marker levels and subsequent response to primary chemotherapy. 相似文献