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91.
Seminoma lesions are characterized by a brisk inflammatory infiltrate containing both CD4 and CD8 T cells, which is of prognostic significance. However, whether seminoma cells express the HLA molecules required for classical T-cell recognition remains controversial. In the present study, we conducted a molecular, phenotypical and functional characterization of tumor infiltrating lymphocytes (TILs) from seminoma lesions. T-cell receptor clonotype mapping demonstrated the presence of clonally expanded T cells in the majority of the lesions. The cytotoxic capacity of TILs was indicated by expression of CD107a, which is a recently described surrogate marker for cytolytic activity. Indeed, the frequency of CD107a positive cells was substantially higher in TILs when compared to peripheral blood mononuclear cells. Moreover, fluorescence activated cell sorting of CD107a positive TILs allowed comparison of the clonotypic T-cell receptor fingerprint and demonstrated the ability of expanded clones to express this cytotoxic marker, suggesting cytotoxic activity at the tumor site. The cytotoxicity was confirmed by in situ granzyme B expression. Furthermore, by staining with multimeric HLA-peptide complexes, we could demonstrate the presence of Mage-3 specific T cells among TILs. In summary, specific and functional T-cell responses are operative in seminoma, indicating that the inflammatory infiltrate is indeed involved in the immunological control of the tumor.  相似文献   
92.
93.
Sheepshead minnows (Cyprinodon variegatus) were continuously exposed to two concentrations of polycyclic aromatic hydrocarbons (PAHs) dissolved in seawater (sigma PAH = 7.57 and 72.31 microg/L) for 36 d, followed by 8 d of depuration. The PAHs studied were naphthalene (NPH or C0-NPH), phenanthrene (PHE or C0-PHE), pyrene (PYR), 2-methylnaphthalene (C1-NPH), 1,3-dimethylnaphthalene (C2-NPH), 2-isopropylnaphthalene (C3-NPH), 9-methylphenanthrene (C1-PHE), and 9-ethylphenanthrene (C2-PHE). Uptake rate constants (k1) for NPHs increased with increasing degree of alkylation and log value of the octanol/water partition coefficient (Kow), whereas k1 values for three- and four-ring PAHs were lower despite their high log Kow values. Elimination rate constants (k2) for the homologue series of NPHs and PHEs generally increased with decreasing degree of alkylation and log Kow values. However, the depuration time did not directly correlate with the molecular size for nonalkylated PAHs. Bioconcentration factors (BCFs) were estimated from the ratio of k1 to k2 and also directly from PAH concentrations in fish tissue and water samples, and the factors generated by the two methods were very similar. A significant positive correlation was determined between log BCFs and log Kow values for the series of C0- through C3-NPH at both low (r2 = 0.985, p = 0.0077) and high (r2 = 0.956, p = 0.022) exposures, although this correlation was not determined for all the PAHs studied. As a result of increased metabolism and/ or reduced bioavailability with increasing lipophilic character, the estimated BCFs for C0- through C2-PHE and PYR were generally lower than those for C0- through C3-NPH. The two exposure levels revealed minor variations in k1 and k2 values for parent PAHs and in the temporal pattern of PAH metabolite concentrations in bile. The present results indicate that the presence and nature of alkyl groups have a significant influence on the kinetics and metabolism of PAHs in fish.  相似文献   
94.
The next few decades will bring about more trade in services, among them health care. This paper describes a recent project on cross-border trading of patients initiated by the Norwegian parliament (The Patient Bridge). This health policy reform met some resistance among hospital physicians. However, patients were willing to participate if being properly informed and supported by local health care workers. The Patient Bridge turned out to be a relatively expensive project partly because of the transaction costs involved (transportation and escort) and partly because of high treatment costs. Excessive treatment costs were a result of insufficient cost-consciousness in the purchasing organization. The Patient Bridge revealed large price differentials not only between Norwegian and foreign hospitals, but also between hospitals abroad, even within the same country. This finding points to the possibilities of reaching mutual gains from trading patients across borders.  相似文献   
95.
Antigen microarray profiling of autoantibodies in rheumatoid arthritis   总被引:10,自引:0,他引:10  
OBJECTIVE: Because rheumatoid arthritis (RA) is a heterogeneous autoimmune disease in terms of disease manifestations, clinical outcomes, and therapeutic responses, we developed and applied a novel antigen microarray technology to identify distinct serum antibody profiles in patients with RA. METHODS: Synovial proteome microarrays, containing 225 peptides and proteins that represent candidate and control antigens, were developed. These arrays were used to profile autoantibodies in randomly selected sera from 2 different cohorts of patients: the Stanford Arthritis Center inception cohort, comprising 18 patients with established RA and 38 controls, and the Arthritis, Rheumatism, and Aging Medical Information System cohort, comprising 58 patients with a clinical diagnosis of RA of <6 months duration. Data were analyzed using the significance analysis of microarrays algorithm, the prediction analysis of microarrays algorithm, and Cluster software. RESULTS: Antigen microarrays demonstrated that autoreactive B cell responses targeting citrullinated epitopes were present in a subset of patients with early RA with features predictive of the development of severe RA. In contrast, autoimmune targeting of the native epitopes contained on synovial arrays, including several human cartilage gp39 peptides and type II collagen, were associated with features predictive of less severe RA. CONCLUSION: Proteomic analysis of autoantibody reactivities provides diagnostic information and allows stratification of patients with early RA into clinically relevant disease subsets.  相似文献   
96.
BACKGROUND: This study presents the number of germ cells and somatic cells in human fetal testes during week 6 to week 9 post conception, i.e. the first weeks following sex differentiation of the testes. METHODS: One testis with attached mesonephros from each of 10 individual legal abortions was used. After recovery of the fetus, the testes were immediately isolated, fixed and processed for histology. The optical fractionator technique, a stereological method, was utilized to estimate the total number of germ cells in ten testes and somatic cells in six of them. RESULTS: The number of germ cells per testis increased from approximately 3000 in week 6 to approximately 30000 in week 9. The ratio of germ cells to Sertoli cells was approximately 1:11 and the ratio of germ cells to somatic cells was approximately 1:44 throughout this period. CONCLUSIONS: For the first time, germ cell and somatic cell number have been determined during early human fetal testis development. Knowledge of the number of germ cells in this period may be very important, because several environmental pollutants are suspected to result in decreased semen quality in men born of mothers exposed to these pollutants during pregnancy.  相似文献   
97.
Clinically, rheumatoid arthritis (RA) is a chronic deforming disease characterized mainly by joint swelling and destruction. Although synovial inflammation and bone erosion are the hallmarks of this disease, the presentation of various features between patients is clearly heterogenous, suggesting that there are different variants of RA. Hence, the development of an animal model that has all of the elements of human RA has remained elusive. This review explores several different views on the etiology of RA and the recent data from various murine arthritis models which provide support for these theories. In addition to discussing the potential roles of CD4+ T cell activation, autoantibodies, and lymphocyte-independent cytokine production, the role of CD4+ T regulatory cells will be presented in the context of a newly developed humanized transgenic mouse model. This novel T cell receptor transgenic model is being characterized to enhance our understanding of the mechanisms involved in the breach of self-tolerance that occurs in autoimmune disorders such as RA.  相似文献   
98.
The possibility that triclosan and PVM/MA (polyvinylmethyl ether/maleic acid) copolymer, additives to dentrifrices, could interact with eukaryotic membrane lipids was studied by two methods: first, by determining the pressure/molecular area isotherms at 37 degrees C of glycerophospholipid monolayers, using the Langmuir technique; and second, by phase-transition parameters in liposomes of the same lipids, using differential scanning calorimetry (DSC). Triclosan interacted, in a concentration-independent manner, with monolayers of saturated phosphatidylcholines (PC; i.e. markers of the outer membrane leaflet of eukaryotic cells). Triclosan and PVM/MA copolymer mixtures were shown to clearly interact in a concentration-dependent manner with PC. Triclosan was found to interact with liposomes of saturated and unsaturated phosphatidylcholines and phosphatidylserines (PS; i.e. markers of the inner membrane leaflet of eukaryotic cells), and saturated ethanolamines (PE; i.e. markers of the inner membrane leaflet of eukaryotic cells), resulting in a decrease of the lipid melting temperature (Tm). PVM/MA copolymer changed the Tm of PS, PC, and PE in different manners. By adding PVM/MA or triclosan-PVM/MA copolymer mixtures to 1-stearoyl-2-oleoyl-sn-glycero-3-phosphoserine (SOPS) no lipid transitions were detected. A biphasic change of the PC transition temperature resulted when triclosan or triclosan PVM/MA copolymer mixtures were added, indicating domain formation and change of the lipid polymorphism.  相似文献   
99.
The outcome of incontinence surgery was studied using a questionnaire, a 24-hour pad test (24hPT), and a stress test (ST). Five to 10 years after a Burch colposuspension, 111 patients were asked to complete the Bristol Female Urinary Tract Symptom Questionnaire (BFLUTS) and to perform a 24hPT and a ST. Eighty-two patients completed the questionnaire and 71 and 69 patients performed the stress and pad tests, respectively. Seventy-three percent of the patients did not leak during the ST and 75% of the patients were not leaking during the 24hPT. Seventy-three percent of the patients stated that they were at least occasionally stress or urge incontinent and 62% stated that they were both stress and urge incontinent. However, only 24% of the stress incontinent and 28% of the urge incontinent patients found their incontinence to be "quite a problem" or "a serious problem." Patients leaking urine only "occasionally," "once a week," leaking "drops," and finding the leakage to be "a bit of a problem" had median leakage 0g during ST and 24hPT. Patients who reported the leakage to occur "sometimes" "most or all of the time" and who found the leakage to be "a bit, quite, or a serious problem" accounted for 20 to 30% of all patients, as did patients leaking during objective tests. Objective tests revealed leakage to occur less frequently compared with self-reported leakage. The BFLUTS questionnaire revealed leakage to occur with varying frequency, amount, and bother. Leakage occurring seldom, of small amount and bother may be of minor clinical importance.  相似文献   
100.
Fukuda M  Fukuda K  Shimizu T  Andersen CY  Byskov AG 《Lancet》2002,359(9315):1407-1408
We assessed whether the smoking habits of parents around the time of conception affects the likelihood of the offspring being male or female. We found that the offspring sex ratio (male to female) was lower when either one or both of the parents smoked more than 20 cigarettes per day compared with couples in which neither of the parents smoked. We found the lowest sex ratio among children whose mothers and fathers both smoked more than 20 cigarettes per day (p<0.0001). Parental periconceptional smoking might be a contributing factor to a lower male to female sex ratio of offspring.  相似文献   
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