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91.
S. I. Aguiar I. Serrano F. R. Pinto J. Melo-Cristino M. Ramirez 《Clinical microbiology and infection》2008,14(9):835-843
The pneumococcal seven-valent conjugate vaccine (PCV7) has been administered in Portugal since late 2001 through the private sector. To evaluate the impact of PCV7 use, the serotypes and antimicrobial susceptibility of pneumococci causing invasive disease in Portugal during 2003–2005 were determined and compared with available data for the period 1999–2002. Changes in serotype distribution compatible with the introduction of PCV7 were shown for children ≤5 years of age from 2003 onwards and for adults from 2004 onwards. PCV7 use with coverage of 43% of children with four doses in the 2004 birth cohort, although substantially below universal coverage, seems to have contributed to greatly reducing the proportion of invasive infections due to vaccine serotypes 4, 6B, 14 and 23F. Similarly, significant indirect effects on the serotype distribution of pneumococci causing infections in adults were noted, with reductions in the proportion of invasive infections caused by serotypes 4, 5 and 14. These changes were accompanied by an increase in the proportion of two non-vaccine serotypes: 19A isolates in all age groups and 7F isolates in adults. Whereas serotypes 6B, 14 and 19A were associated with multidrug resistance, isolates expressing serotypes 4 and 7F were fully susceptible for the most part. There were no changes in the proportion of resistant isolates within each serotype and, in spite of the changes in serotype prevalence, there was not an overall reduction in the proportion of infections caused by resistant pneumococci. 相似文献
92.
5-HT1A dysfunction in borderline personality disorder 总被引:2,自引:0,他引:2
Hansenne M Pitchot W Pinto E Reggers J Scantamburlo G Fuchs S Pirard S Ansseau M 《Psychological medicine》2002,32(5):935-941
BACKGROUND: A number of challenge studies have reported abnormalities of serotonergic function in borderline personality disorder (BPD). There are, however, problems with the pharmacological probes used in these studies since fenfluramine and m-CPP are not only serotonergic agents but also induce release of catecholamines, particularly dopamine. Therefore, we tested whether subjects with BPD showed a blunted prolactin (PRL) response to flesinoxan, a highly potent and selective 5-HT1A agonist. METHODS: Flesinoxan challenge test was carried out in 20 BPD in-patients and 20 healthy controls matched for gender but not for age. Since 16 BPD in-patients exhibited major depressive co-morbidity, a group of 20 depressed in-patients matched for gender but not for age was also included. RESULTS: BPD in-patients exhibited blunted PRL responses as compared to controls, whereas depressed in-patients did not differ from controls. Moreover, PRL responses were lower among BPD in-patients than among depressed in-patients. Among the BPD in-patients, PRL responses to flesinoxan were lower in patients with past history of suicide attempts (N = 8) than in those with a negative history. CONCLUSIONS: The results show major involvement of serotonergic function in BPD and are consistent with previous studies linking lower serotonergic activity with impulsivity. More particularly, our data suggest that BPD is characterized by lower 5-HT1A receptor sensitivity. Moreover, the data support the involvement of 5-HT1A activity in suicidal behaviour. However, this conclusion is limited because other hormonal responses such as ACTH and cortisol were not assessed, and because BPD was assessed by a self-report questionnaire and not a structured clinical interview. 相似文献
93.
Monocytoid B-cell lymphoma with bone marrow and peripheral blood involvement at presentation 总被引:3,自引:0,他引:3
A Carbone A Gloghini A Pinto V Attadia V Zagonel R Volpe 《American journal of clinical pathology》1989,92(2):228-236
A case of malignant lymphoma showing in a lymph node the characteristic morphologic features of the so-called monocytoid B-cell lymphoma (MBCL) is described. This case differs from the reported cases in the literature because atypical cells were observed in the bone marrow biopsy and marrow and peripheral blood smears that were obtained from the patient, a 61-year-old man, during the staging procedures. Lymphocyte surface marker studies on peripheral blood by flow cytometry and DNA analysis revealed a monoclonal population of lambda-positive lymphocytes. The immunophenotype of MBCL cells was studied both in paraffin-embedded lymph node sections by immunoperoxidase method and in peripheral blood by flow cytometric analysis; the cells expressed the SIg with lambda light chain restriction and the HLA-DR antigen; they also had positive results for B-cell-associated antigens, including LN1, LN2, CD 20, CD 22, CD 19, CD 9 but not CD 21, CD 24, and CD 10, T-cell-associated antigens and monocytic markers. In addition, they had negative results for CD 25, CD 38, PCA-1. This report emphasizes that in MBCL, peripheral and marrow involvement may occur at presentation analogous to other low-grade B-cell lymphomas. The immunophenotypic characteristics of MBCL cells, though not pathognomonic, are considered to be helpful in differentiating them from circulating cells of other B-cell lymphomas. 相似文献
94.
An antigen-competitive enzyme-linked immunosorbent assay (Ag-C-ELISA) was developed for the detection of infectious bronchitis virus (IBV) antigens, M41 strain, in tissues from experimentally infected chickens, or in allantoic fluid harvested from inoculated embryonated eggs. The detection limit of IBV in the Ag-C-ELISA was 104.1 median embryo infective doses (EID50)/well. Tracheal and lung samples from chickens vaccinated with 102.5 EID50 of live attenuated infectious bronchitis (H120) vaccine were negative in the direct detection Ag-C-ELISA. The results indicate that the Ag-C-ELISA has the potential to detect IBV, either directly in tissue samples or when combined with the passage of material in embryonated eggs, thereby constituting an alternative method for the diagnosis of IBV. 相似文献
95.
Alvaro P Pinto AP Felipe F B Tuon Luiz Fernando Bleggi Torres Luiz Martins Colla?o 《Diagnostic cytopathology》2002,26(1):15-18
The present study sought possible factors leading to the cytological diagnosis of atypical squamous cells of uncertain significance (ASCUS) in cases of high-grade squamous intraepithelial lesions (HSIL). Based on retrospective histopathological analysis of loop electrical excision procedure (LEEP) products that diagnosed HSIL, two study groups were randomly selected. The first was consisted of cases with two consecutive Papanicolaou (Pap) smears with the diagnosis of ASCUS. The second (control) group was represented by cases diagnosed as HSIL by cytology. From the Pap smears diagnosed as ASCUS, the sampling limitations was different from control group (P < 0.05). The median size of the largest lesion in each case with ASCUS was 2.66 mm (+/- 1.71 mm). In the control group, the median size of the largest lesion was 5.15 mm (+/-2.58 mm) (P < 0.05). The size of the lesion and sample limitations led patients with cervical intraepithelial neoplasms to be diagnosed as ASCUS for two consecutive times, after a 6-mo period. 相似文献
96.
Tripodi A 《Pathophysiology of haemostasis and thrombosis》2002,32(5-6):245-248
Until recently the laboratory diagnosis of thrombophilia consisted on investigation of the plasmatic anticoagulant pathways and the search for dysfibrinogenemia and antiphospholipid antibodies/lupus anticoagulants. More recently, the laboratory investigation has been expanded by including activated protein C (APC) resistance, due or not to the presence of the factor V Leiden mutation; hyperprothrombinemia, due to the presence of the prothrombin mutation G20210A and hyperhomocysteinemia, due to impairment of the relevant metabolic pathway because of enzymatic and/or vitamin deficiency. Testing for thrombophilia may be useful for many reasons. First, the results of testing may provide valuable information to assess the risk of recurrence in the proband. Second, testing family members is useful for prophylactic and diagnostic purposes. Third, the identification of patients bearing combined defect helps to identify those at increased risk for thrombosis. Testing is recommended for patients with a past history of thrombosis and should be extended to their first-degree family members. Since most of the tests are not reliable during anticoagulation, it is preferable to postpone laboratory testing until after discontinuation of the treatment. Whenever possible testing should be performed by means of functional assays. DNA analysis is required for the prothrombin mutation G20210A. Laboratory diagnosis for antiphospholipid antibodies/lupus anticoagulant should be performed by a combination of tests including phospholipid-dependent clotting assays and solid phase anticardiolipin antibodies. Hyperhomocysteinemia may be assessed by high-pressure liquid chromatography methods, or by fluorescence polarization immunoassays. 相似文献
97.
Recent advances in the study of evoked responses settled a definition of transient and steady-state visual evoked responses (VER) and discovered the existence of Temporal Frequency Regions in humans. This paper reports data from visual responses evoked by low and high frequency stimuli. White flashes were performed in albino Sprague Dawley rats from 7 to 90 days of age. Frequency analysis technique offered the possibility to evaluate the amplitude parameters and their variations dependent on intensity of luminance and on development. The responses suggested the existence of two temporal frequency regions in the rat: a first one at about 8 Hz, related to high frequencies of EEG, a second one at frequencies ranging from 12 to 24 Hz, related to luminance sensitivity. The development of the second region is correspondent to the complete development of transient VER parameters. 相似文献
98.
Direct estimation of the frequency of human cytotoxic T lymphocytes and their precursors following in vitro allosensitization 总被引:2,自引:0,他引:2
Cell mediated lympholysis (CML) has been proposed as an in vitro model of the rejection process that results from transplantation of allogeneic tissue. To date, the absolute frequencies of cytotoxic T lymphocytes (CTL) and their precursors (CTL.P) have not been directly estimated in man because of technical difficulties. Through optimizing the conditions for radiometric detection of 51Cr release and the attendant improvement in CML sensitivity, direct CTL frequency estimates have been determined in peripheral blood (PBL), spleen (SPL), and lymph nodes (LNC) after in vitro allostimulation using unrelated human cells and limiting dilution assays. The mean frequency of CTL generated from PBL is 1 in 826 cells (0.121% +/- 0.101%) which, from preliminary experiments, is significantly greater than that generated from either LNC or SPL (p less than 0.05). With restimulation of primed cells on day 10, the frequency of CTL generated from PBL was increased 400%. The CTL.P frequency (0.0064% +/- 0.0050%) was approximately 5% of the corresponding CTL frequency. The CTL.P frequencies were found to be minimal estimates as both accessory "filler" cells and T cell growth factors increased the level of detection of CTL.P an average of threefold. The limiting cell dilution assay as detailed in this report should be a powerful tool for defining the cellular requirements and related factors necessary for optimal induction of a CTL response and should provide the means for determination of the immunogenetic requirements and the allospecificity of human cytotoxic lymphocytes. 相似文献
99.
M M Pinto L H Bernstein R A Rudolph D A Brogan M Rosman 《Archives of pathology & laboratory medicine》1992,116(6):626-631
In our previous study, the combination of the concentrations of carcinoembryonic antigen (CEA) and CA125 and the findings from cytological examination in 189 benign and malignant pleural and peritoneal effusions was useful in the diagnosis/classification of malignant effusions. Sensitivity of CEA (level, greater than 5 ng/mL) was 68%; specificity was 99% for the diagnosis of malignant effusions secondary to carcinoma of the lung, breast, gastrointestinal tract, and mucinous carcinoma of the ovary. Sensitivity of CA125 (level, greater than 5000 U/mL) was 85%; specificity was 96% for the diagnosis of malignant effusions in carcinoma of the ovary, fallopian tube, and endometrium. We now expanded the study to include 840 pleural and peritoneal effusions (benign, n = 520; malignant, n = 320) and analyzed the data by the statistical method of Rudolph and colleagues. Based on new cutoff values, ie, CEA level at 6.3 ng/mL and CA125 level at 3652 U/mL, the sensitivities for detection of malignant effusions secondary to carcinomas of the lung, breast, and gastrointestinal tract and mucinous carcinoma of the ovary varied between 75% and 100%; specificity was 98%. Sensitivity of CA125 for detection of malignant effusions from müllerian epithelial carcinoma was 71%; specificity was 99%. The elevated CEA fluid level alone helped to diagnose malignant effusions of the gastrointestinal tract in 54%, breast in 19%, and lung in 16%. The high CA125 fluid level was predictive of müllerian epithelial carcinoma. Adjunctive use of CEA and CA125 levels in fluid enhances the sensitivity of cytological diagnosis and may be predictive of the primary site in patients who present with carcinoma of an unknown primary source. 相似文献
100.
Borsari V Giavaresi G Fini M Torricelli P Tschon M Chiesa R Chiusoli L Salito A Volpert A Giardino R 《Biomaterials》2005,26(24):4948-4955
A new implant surface has been developed with the purpose of avoiding as much stress shielding as possible, and thus prolong the prosthesis lifespan. The aim of this study was to investigate the in vitro effect of this new ultra-high roughness and dense Titanium (Ti) surface (PG60, Ra = 74 microm) in comparison with medium (TI01, Ra = 18 microm) and high (TI60, Ra = 40 microm) roughness and open porous coatings; all the coatings were obtained by vacuum plasma spraying. MG63 osteoblast-like cells were seeded on the tested materials and polystyrene, as control, for 3 and 7 days. Cells proliferated on the material surfaces similarly to the control. Alkaline phosphatase activity had lower values for TI60 than TI01 (p < 0.0005) and PG60 (p < 0.005). Osteocalcin levels measured on TI60 were significantly (p < 0.0005) lower in comparison with TI01 and PG60 at 7 days. Procollagen-I synthesis reduced with increasing roughness and the lowest data was found for PG60. While at 3 days Transforming Growth Factor beta1 levels augmented with increasing roughness, at 7 days TI60, the high roughness surface, was significantly lower than PG60 (p < 0.005) and TI01 (p < 0.001). All tested materials showed significantly higher Interleukin-6 levels than those of polystyrene at both experimental times. Nitric Oxide activity on TI01 was significantly (p < 0.05) higher than on TI60 and polystyrene. In conclusion, the new ultra-high roughness and dense coating PG60 provided a good biological response, even though, at least in vitro, it behaved similarly to the coatings already used in orthopaedics. 相似文献