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991.
CD8 T cells are necessary for controlling tumors induced by mouse polyoma virus (PyV), but the effector mechanism(s) responsible have not been determined. We examined the PyV tumorigenicity in C57BL/6 mice mutated in Fas or carrying targeted disruptions in the perforin gene or in both TNF receptor type I and type II genes. Surprisingly, none of these mice developed tumors. Perforin/Fas double-deficient radiation bone marrow chimeric mice were also resistant to PyV-induced tumors. Anti-PyV CD8 T cells in perforin-deficient mice were found not to differ from wild type mice with respect to phenotype, capacity to produce cytokines or maintenance of memory T cells, indicating that perforin does not modulate the PyV-specific CD8 T cell response. In addition, virus was cleared and persisted to similar extents in wild type and perforin-deficient mice. In summary, perforin/granzyme exocytosis is not an essential effector pathway for protection against PyV infection or tumorigenesis. 相似文献
992.
Control of in vitro tissue-engineered bone-like structures using human mesenchymal stem cells and porous silk scaffolds 总被引:17,自引:0,他引:17
Hofmann S Hagenmüller H Koch AM Müller R Vunjak-Novakovic G Kaplan DL Merkle HP Meinel L 《Biomaterials》2007,28(6):1152-1162
Natural bone consists of cortical and trabecular morphologies, the latter having variable pore sizes. This study aims at engineering different bone-like structures using scaffolds with small pores (112-224 microm) in diameter on one side and large pores (400-500 microm) on the other, while keeping scaffold porosities constant among groups. We hypothesized that tissue engineered bone-like structure resulting from silk fibroin (SF) implants is pre-determined by the scaffolds' geometry. To test this hypothesis, SF scaffolds with different pore diameters were prepared and seeded with human mesenchymal stem cells (hMSC). As compared to static seeding, dynamic cell seeding in spinner flasks resulted in equal cell viability and proliferation, and better cell distribution throughout the scaffold as visualized by histology and confocal microscopy, and was, therefore, selected for subsequent differentiation studies. Differentiation of hMSC in osteogenic cell culture medium in spinner flasks for 3 and 5 weeks resulted in increased alkaline phosphatase activity and calcium deposition when compared to control medium. Micro-computed tomography (microCT) detailed the pore structures of the newly formed tissue and suggested that the structure of tissue-engineered bone was controlled by the underlying scaffold geometry. 相似文献
993.
Roth B Enders M Arents A Pfitzner A Terletskaia-Ladwig E 《Journal of medical virology》2007,79(7):956-962
From 2000 to 2005, a total of 1,096 enterovirus infections were diagnosed either by isolation of virus from cell culture or by RT-PCR (5'non-coding region (NCR)). Typing of viruses (n = 674) was carried out by immunofluorescence with monoclonal antibodies, neutralization test or molecular methods. Seasons with high enterovirus activity were characterized by high prevalence of echovirus 30 (62.2% in 2000, 25.5% in 2001) and echovirus 13 (34.5% in 2001). In contrast, in the 2003 season, which had very low enterovirus activity, these types were rare. During this season, cell culture sensitivity (human colonic carcinoma cells and human embryonic lung fibroblasts (HEL)) was exceptionally low. In order to determine the type of "non-cultivable" enteroviruses, purified RNA from selected stool samples was subjected to direct molecular typing. VP1/2A-specific fragments were amplified by RT-PCR, cloned and sequenced. The predominant virus identified was coxsackie A. Consequently, rhabdomyosarcom cells were introduced into the daily routine, which improved the isolation of enteroviruses. Echovirus 30 was again most commonly isolated during seasons 2004 and 2005 with increasing enterovirus activity. In conclusion, high prevalence of echovirus 30 and 13 is indicative of seasons with high enterovirus activity. The type of circulating enteroviruses may influence isolation of enterovirus from cell culture. RT-PCR (VP1/2A) combined with cloning and sequencing of amplicons is a useful tool for viral typing directly from stool samples. In cases of severe enterovirus infection, virological diagnosis should not solely rely on virus isolation from cell culture. 相似文献
994.
Improved efficacy of a licensed acellular pertussis vaccine, reformulated in an adjuvant emulsion of liposomes in oil, in a murine model
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Mansour M Brown RG Morris A Smith B Halperin SA 《Clinical and Vaccine Immunology : CVI》2007,14(10):1381-1383
The immunogenicities and efficacies of a licensed diphtheria, tetanus, acellular pertussis, and inactivated poliovirus vaccine and the same vaccine formulated in a liposome/oil emulsion adjuvant were compared in a mouse model of pertussis respiratory infection. A single dose of the liposome/oil emulsion-adjuvanted vaccine produced significantly higher antibody levels than one dose of the licensed vaccine and protected mice from Bordetella pertussis infection with an efficacy equivalent to that of three doses of the licensed vaccine. 相似文献
995.
A seasonal investigation on the occurrence of fishborne zoonotic trematodes (FZT) in economically important mono-cultured
hybrid catfish and giant gouramy was conducted in the Mekong Delta of Vietnam. Fish from carp poly-culture and intensive small-scale
integrated vegetable–aquaculture–animal husbandry farming (VAC) systems were also examined. No FZT metacercariae were found
in any mono-cultured hybrid catfish. FZT metacercariae were common, however, in fish from the other three systems: All metacercariae
belonged to the Heterophyidae family of trematodes, Haplorchis pumilio, H. taichui, Centrocestus formosanus and Stellantchasmus falcatus. The FZT prevalence was 1.7% in mono-cultured giant gouramy, 6.6% in carp from the poly-culture and 3.0% in fish raised in
the VAC system. H. pumilio was the most common FZT species constituting more than 58.0% of all metacercariae recovered. The prevalence of infection
was significantly higher in the flooding season compared to the non-flooding season for both giant gouramy and fish reared
in the VAC system. FZT intensity was greatest in fish from carp poly-culture, particularly in the flooding season. The results
indicate that certain fish production systems are at risk for FZT, and control approaches will benefit from understanding
these risk factors. 相似文献
996.
Nimphius W Moll R Olbert P Ramaswamy A Barth PJ 《Virchows Archiv : an international journal of pathology》2007,450(2):179-185
CD34+ fibrocytes are constitutive elements of the connective tissue where they play a role in matrix synthesis and tumor-associated
stromal remodeling. Secreted protein, acidic, and rich in cysteine (SPARC) is a pivotal mediator of stromal remodeling precipitated
by invasive carcinomas. The present study was undertaken to investigate CD34+ fibrocytes in the stroma of the tumor-free urinary bladder, chronic cystitis, and urothelial carcinomas together with stromal
expression of α-smooth muscle actin (α-SMA), CD117, and SPARC. In tumor-free urinary bladder and chronic cystitis, CD34+ fibrocytes were found in the deep lamina propria and tunica muscularis, whereas the superficial lamina propria disclosed
a CD34-negative and α-SMA-positive fibrocyte-like cell. Invasive urothelial carcinomas revealed a complete loss of CD34+ fibrocytes and concomitant appearance of α-SMA-reactive myofibroblasts which showed strong expression of SPARC. CD117 expression
of tumor-free and tumor-associated stroma revealed no differences. We in this study for the first time describe CD34+ fibrocytes in the urinary bladder and an up-to-now unknown population of α-SMA-positive fibrocytes exclusively occurring
in the superficial lamina propria. Stromal remodeling associated with invasive carcinomas in the urinary bladder is characterized
by a loss of CD34+ fibrocytes paralleled by a gain of α-SMA-positive myofibroblasts and increased expression of SPARC. 相似文献
997.
Weber MA Kinscherf R Krakowski-Roosen H Aulmann M Renk H Künkele A Edler L Kauczor HU Hildebrandt W 《Journal of molecular medicine (Berlin, Germany)》2007,85(8):887-896
Progressive muscle wasting is a central feature of cancer-related cachexia and has been recognized as a determinant of poor prognosis and quality of life. However, until now, no easily assessable clinical marker exists that allows to predict or to track muscle wasting. The present study evaluated the potential of myoglobin (MG) plasma levels to indicate wasting of large locomotor muscles and, moreover, to reflect the loss of MG-rich fiber types, which are most relevant for daily performance. In 17 cancer-cachectic patients (weight loss 22%) and 27 age- and gender-matched healthy controls, we determined plasma levels of MG and creatine kinase (CK), maximal quadriceps muscle cross-sectional area (CSA) by magnetic resonance imaging, muscle morphology and fiber composition in biopsies from the vastus lateralis muscle, body cell mass (BCM) by impedance technique as well as maximal oxygen uptake (VO(2)max). In cachectic patients, plasma MG, muscle CSA, BCM, and VO(2)max were 30-35% below control levels. MG showed a significant positive correlation to total muscle CSA (r = 0.65, p < 0.001) and to the CSA fraction formed by type 1 and 2a fibers (r = 0.80, p < 0.001). However, when adjusted for body height and age by multiple regression, MG yielded a largely improved prediction of total CSA (multiple r = 0.83, p < 0.001) and of fiber type 1 and 2a CSA (multiple r = 0.89, p < 0.001). The correlations between CK and these muscle parameters were weaker, and elevated CK values were observed in 20% of control subjects despite a prior abstinence from exercise for 5 days. In conclusion, plasma MG, when adjusted for anthropometric parameters unaffected by weight, may be considered as a novel marker of muscle mass (CSA) indicating best the mass of MG-rich type 1 and 2a fibers as well as VO(2)max as an important functional readout. CK plasma levels appear to be less reliable because prolonged increases are observed in even subclinical myopathies or after exercise. Notably, cancer-related muscle wasting was not associated with increases in plasma MG or CK in this study. 相似文献
998.
Majewski M Bose TO Sillé FC Pollington AM Fiebiger E Boes M 《International immunology》2007,19(6):719-732
Maturation of dendritic cells (DCs) regulates protein sorting in endosomal compartments to promote the surface expression of molecules involved in T cell activation. MHC Class II complexes are mobilized to the surface via intracellular effector molecules that remain largely unknown. We here show that protein kinase C (PKC) stimulates Class II antigen surface expression, using knock-in mice that express a Class II-green fluorescent protein fusion protein as a read out. Selective inhibition of PKCdelta counteracts the ability of DCs to stimulate Class II MHC-restricted antigen-specific T cells. Activation of PKC does not affect antigen uptake, peptide loading and surface display of Class I MHC and transferrin receptor in DCs. We show that activation-induced Class II MHC surface expression is dependent on activation of PKCdelta and conclude that this event is pivotal for optimal CD4 T cell activation. 相似文献
999.
Background
This paper reports the findings of an exploratory study about the information women diagnosed with Polycystic Ovarian Syndrome (PCOS) want to know about their condition and the consequences of this information for future treatment and health outcomes.Methods
In-depth qualitative interviews regarding their information needs were undertaken with ten South Australian women diagnosed with PCOS. These women were aged 28–38 years and at differing stages of their fertility experience. The time since diagnosis ranged from 1–17 years. The main outcome measures sought were the identification of the information needs of women diagnosed with Polycystic Ovarian Syndrome (PCOS) during different periods of their lives; how and where they obtain this information, and the consequences of this information for future treatment and health outcomes.Results
The women with PCOS in this study preferentially used the Internet for their information needs, as it had the advantages of convenience, privacy and accessibility, when compared with traditional mechanisms of information provision.Conclusion
Giving a name to a collection of symptoms may bring relief and provide recognition that there really is a problem. However, with a diagnosis comes the need to have questions answered. A diagnosis of a chronic condition such as PCOS necessitates decision-making regarding possible treatment strategies and lifestyle choices. Information is needed in order to participate in shared decision making. The Internet proved to be a most versatile and beneficial source of information source for women with PCOS, if its limitations are taken into consideration. 相似文献1000.
Objective Dental erosion is characterized as a disorder witha multifactorial aetiology including environmental acid exposure.The purpose of this article was to summarize and discuss theavailable information concerning occupational dental erosion. Methods Information from original scientific papers, case reportsand reviews with additional case reports listed in PubMed, Medlineor EMBASE [search term: (dental OR enamel OR dentin) AND (erosionOR tooth wear) AND (occupational OR worker)] were included inthe review. References from the identified publications weremanually searched to identify additional relevant articles. Results The systematic search resulted in 59 papers, of which42 were suitable for the present review. Seventeen papers demonstratedevidence that battery, galvanizing and associated workers exposedto sulphuric or hydrochloric acid were at higher risk of dentalerosion. For other industrial workers, wine tasters and competitiveswimmers, only a few clinical studies exist and these do notallow the drawing of definitive conclusions. Conclusion Occupational acid exposure might increase the riskof dental erosion. Evidence for occupational dental erosionis limited to battery and galvanizing workers, while data forother occupational groups need to be confirmed by further studies. 相似文献