GB virus type C infection modulates T-cell activation independently of HIV-1 viral load

Background: Many clinical studies have suggested a beneficial effect of GB virus type C (GBV-C) on the course of HIV-1 infection, but the mechanisms involved in such amelioration are not clear. As recent evidence has implicated cellular activation in HIV-1 pathogenesis, we investigated the effect of GBV-C viremia on T-cell activation in early HIV-1 infection. Methods: Forty-eight recently infected HIV-1 patients (23 GBV-C viremic) were evaluated for T-cell counts, expanded immunophenotyping GBV-C RNA detection, and HIV-1 viral load. Nonparametric univariate and multivariate analyses were carried out to identify variables associated with cellular activation, including GBV-C status, HIV-1 viral load, T lymphocyte counts, and CD38 and chemokine (C-C motif) receptor 5 (CCR5) surface expression. Finding: We not only confirmed the positive correlation between HIV-1 viral load and the percentage of T cells positive for CD38(+)CD8(+) but also observed that GBV-C viremic patients had a lower percentage of T cells positive for CD38(+)CD4(+), CD38(+)CD8(+), CCR5(+)CD4(+), and CCR5(+)CD8(+) compared with HIV-1-infected patients who were not GBV-C viremic. In regression models, GBV-C RNA(+) status was associated with a reduction in the CD38 on CD4(+) or CD8(+) T cells and CCR5(+) on CD8(+) T cells, independent of the HIV-1 viral load or CD4(+) and CD8(+) T-cell counts. These results were also supported by the lower expression of CD69 and CD25 in GBV-C viremic patients. Interpretation: The association between GBV-C replication and lower T-cell activation may be a key mechanism involved in the protection conferred by this virus against HIV-1 disease progression to immunodeficiency in HIV-1-infected patients. (C) 2009 Wolters Kluwer Health | Lippincott Williams & Wilkins

Lower cytokine secretion ex vivo by natural killer T cells in HIV-infected individuals is associated with higher CD161 expression

Objective: Natural killer T (NKT) cells are efficiently targeted by HIV and severely reduced in numbers in the circulation of infected individuals. The functional capacity of the remaining NKT cells in HIV-infected individuals is poorly characterized. This study measured NKT cell cytokine production directly ex vivo and compared these responses with both the disease status and NKT subset distribution of individual patients. Methods: NKT cell frequencies, subsets, and ex-vivo effector functions were measured in the peripheral blood mononuclear cells of HIV-infected patients and healthy controls by flow cytometry. We measured cytokines from NKT cells after stimulation with either a-galactosyl ceramide-loaded CD1d dimers (DimerX-alpha GalCer) or phorbol myristate acetate and ionomycin. Results: The frequencies of NKT cells secreting interferon-gamma and tumor necrosis factor-alpha were significantly lower in HIV-infected patients than healthy controls after DimerX-alpha GalCer treatment, but responses were similar after treatment with phorbol myristate acetate and ionomycin. The magnitude of the interferon-gamma response to DimerX-alpha GalCer correlated inversely with the number of years of infection. Both interferon-gamma and tumor necrosis factor-alpha production in response to DimerX-alpha GalCer correlated inversely with CD161 expression. Conclusion: The ex-vivo Th1 responses of circulating NKT cells to CD1d-glycolipid complexes are impaired in HIV-infected patients. NKT cell functions may be progressively lost over time in HIV infection, and CD161 is implicated in the regulation of NKT cell responsiveness. (C) 2009 Wolters Kluwer Health vertical bar Lippincott Williams & Wilkins

A randomised controlled trial evaluating the effect of immersion bath on labour pain

Objective: to evaluate the effect of an immersion bath on pain magnitude during the first stage of tabour. Design: a randomised controlled trial comparing the pain scores of bathing and non-bathing nulliparous women during birth was employed. Setting: the study was conducted at the Normal Birth Center of Amparo Maternal, Sao Paulo, Brazil. Participants: 108 birthing women, with 54 women randomly assigned to each group. Interventions: when the birthing women presented at 6-7cm of cervical dilation, they were placed in an immersion bath for 60 mins. Outcome measures: pain scores, using a behavioural pain scale and a numeric scale, were recorded at two evaluation time points: at 6-7cm of cervical dilation and 1 h after the first pain score evaluation. Findings: at the first evaluation, on the behavioural scale, the means were 2.1 for both groups (p = 0.914; 95% confidence intervals (CI) 1.9-2.3 for the control group and 2.0-2.2 for the experimental group). On the numeric scale, the means were 8.7 and 8.5 for the control and experimental groups, respectively (p = 0.235; 95% Cl 8.2-9.2 for the control group and 8.1-8.9 for the experimental group). At the second evaluation, the pain score means for both scales were statistically higher in the control group than in the experimental group. On the behavioural scale, the scores were 2.4 vs. 1.9, respectively, for the control and experimental groups (p<0.001; 95% Cl 2.2-2.6 for the control group and 1.7-2.1 for the experimental group). On the numeric scale, the scores were 9.3 vs. 8.5, respectively, for the control and experimental groups (p<0.05; 95% Cl 8.9-9.7 for the control group and 8.1-8.9 for the experimental group). Conclusions: mean tabour pain scores in the control group were significantly higher than those in the experimental group. The present findings suggest that use of an immersion bath is a suitable alternative form of pain relief for women during tabour. (C) 2007 Elsevier Ltd. All rights reserved.

Comparison of pelvic floor muscle strength between women undergoing vaginal delivery, cesarean section, and nulliparae using a perineometer and digital palpation

Objectives. To compare pelvic floor muscle (PFM) strength between women undergoing vaginal delivery, cesarean section, and nulliparae, investigating the factors associated with PFM strength, and observing the correlation between vaginal digital palpation and use of a perineometer. Methods. A cross-sectional study was conducted, including 31 women following vaginal delivery, 30 women following cesarean section, and 30 nulliparous women. PFM strength was measured by vaginal digital palpation and use of a perineometer. Multiple linear regression analysis with adjustment for covariables was used to compare the mean PFM strength and identify its associated factors. Results. The mean PFM strength of women undergoing vaginal delivery and cesarean section was 25.6 +/- 14.5 cmH(2)O and 39.6 +/- 22.0 cmH(2)O (p < 0.01, adjusted for covariables), respectively. A correlation was observed between measurements of PFM strength obtained by vaginal digital palpation and use of a perineometer (tau = 0.82; p < 0.01). The non-white race/ethnicity was negatively associated with PFM strength (coefficient: -10.2424; p = 0.02). Conclusions. A lower PFM strength was observed in women with a history of vaginal delivery compared to those undergoing cesarean section. Non-white race/ethnicity negatively affected PFM strength. Our data suggest that vaginal digital palpation may be used in clinical practice because of its expressive correlation with use of a perineometer.

Transplacental Transfer of Iron in the Water Buffalo (Bubalus bubalis): Uteroferrin and Erythrophagocytosis

The objectives of this investigation were to understand transplacental transport of iron by secreted uteroferrin (UF) and haemophagous areas of water buffalo placenta and clarify the role(s) of blood extravasation at the placental-maternal interface. Placentomes and interplacentomal region of 51 placentae at various stages of gestation were fixed, processed for light and transmission electron microscopy, histochemistry and immunohistochemistry. Haemophagous areas were present in placentomes collected between 4 and 10 months of pregnancy. Perl`s reaction for ferric iron was negative in placentomes, but positive in endometrial glands. Positive staining for UF indicated areas in which it was being taken up by phagocytosis and/or fluid phase pinocytosis in areolae of the interplacentomal mesenchyme, with little staining in endometrial stroma. Imunohistochemistry detected UF in trophectoderm of haemophagous regions of placentomes and in other parts of the foetal villous tree, but the strongest immunostaining was in the epithelial cells and lumen of uterine glands. Ultrastructural analyses indicated that erythrophagocytosis was occurring and that erythrocytes were present inside cells of the chorion that also contained endocytic vesicles and caveolae. Results of this study indicate that both the haemophagous areas of placentomes and the areolae at the interface between chorion and endometrial glands are important sites for iron transfer from mother to foetal-placental tissues in buffalo throughout pregnancy.

Composite pre-heating: Effects on marginal adaptation, degree of conversion and mechanical properties

Objectives. This study evaluated the effect of composite pre-polymerization temperature and energy density on the marginal adaptation (MA), degree of conversion (DC), flexural strength (FS), and polymer cross-linking (PCL) of a resin composite (Filtek Z350, 3M/ESPE). Methods. For MA, class V cavities (4mmx2mmx2mm) were prepared in 40 bovine incisors. The adhesive system Adper Single Bond 2 (3M/ESPE) was applied. Before being placed in the cavities, the resin composite was either kept at room-temperature (25 degrees C) or previously pre-heated to 68 degrees C in the Calset (TM) device (AdDent Inc., Danbury, CT, USA). The composite was then light polymerized for 20 or 40s at 600mW/cm(2) (12 or 24 J/cm(2), respectively). The percentage of gaps was analyzed by scanning electron microscopy, after sectioning the restorations and preparing epoxy resin replicas. DC (n = 3) was obtained by FT-Raman spectroscopy on irradiated and non-irradiated composite surfaces. FS (n = 10) was measured by the three-point-bending test. KHN (n = 6) was measured after 24h dry storage and again after immersion in 100% ethanol solution for 24 h, to calculate PCL density. Data were analyzed by appropriate statistical analyses. Results. The pre-heated composite showed better MA than the room-temperature groups. A higher number of gaps were observed in the room-temperature groups, irrespective of the energy density, mainly in the axial wall (p < 0.05). Composite pre-heating and energy density did not affect the DC, FS and PCL (p > 0.05). Significance. Pre-heating the composite prior to light polymerization similar in a clinical situation did not alter the mechanical properties and monomer conversion of the composite, but provided enhanced composite adaptation to cavity walls. (C) 2010 Academy of Dental Materials. Published by Elsevier Ltd. All rights reserved.

The role of dentists in-diagnosing osteogenesis imperfecta in patients with dentinogenesis imperfecta

Background. Osteogenesis imperfecta (OI), also known as ""brittle bone disease,"" can be difficult to diagnose in its mild form. The authors describe a clinical case of a diagnosis of dentinogenesis imperfecta (DI), In which a literature review combined with an analysis of dental alterations led to indications of OI involvement. Case Description. Since DI can be associated with OI, the authors reviewed correlated studies and obtained a new medical history from the patient. They then conducted a radiographic and clinical examination of the dentition and submitted an affected third molar to scanning electron microscopy analysis. They compared their findings with descriptions of OI type I dental alterations in the literature and confirmed their diagnosis by means of a medical evaluation. Clinical Implications. In cases in which DI is diagnosed, patients should be examined carefully and the occurrence of OI should be considered `since, in its mild form, it might be misdiagnosed.

Application of abrupt cut-off models in the analysis of the capacitance spectra of conjugated polymer devices

In this paper, a detailed study of the capacitance spectra obtained from Au/doped-polyaniline/Al structures in the frequency domain (0.05 Hz-10 MHz), and at different temperatures (150-340 K) is carried out. The capacitance spectra behavior in semiconductors can be appropriately described by using abrupt cut-off models, since they assume that the electronic gap states that can follow the ac modulation have response times varying rapidly with a certain abscissa, which is dependent on both temperature and frequency. Two models based on the abrupt cut-off concept, formerly developed to describe inorganic semiconductor devices, have been used to analyze the capacitance spectra of devices based on doped polyaniline (PANI), which is a well-known polymeric semiconductor with innumerous potential technological applications. The application of these models allowed the determination of significant parameters, such as Debye length (approximate to 20 nm), position of bulk Fermi level (approximate to 320 meV) and associated density of states (approximate to 2x10(18) eV(-1) cm(-3)), width of the space charge region (approximate to 70 nm), built-in potential (approximate to 780 meV), and the gap states` distribution.

HYDROTHERMAL REE FLUOROCARBONATE MINERALIZATION AT BARRA DO ITAPIRAPUA, A MULTIPLE STOCKWORK CARBONATITE, SOUTHERN BRAZIL

The Barra do Itapirapua ( BIT) carbonatites in southern Brazil belong to the final stages of the Early Cretaceous alkaline rock - carbonatite magmatism of the Ponta Grossa Arch Province. The BIT complex is a dyke and vein stockwork in which four main carbonatitic phases are recognized, mainly magnesiocarbonatites and ferrocarbonatites. These carbonatites are generally overprinted by pervasive hydrothermal events. The C-O stable isotopic data indicate re-equilibration under hydrothermal conditions at temperatures between 375 and 80 degrees C. Significant amounts of REE fluorocarbonate minerals, relatively Sr- and Th-rich, were deposited. Syntaxy between synchysite-(Ce) and parisite-(Ce) is very common owing to the similarity in structures, with alternating (001) layers of (CeF), (CO3) and (Ca). However, bastnasite-(Ce) occurs as individual crystals, overgrown by the synchysite and parisite polycrystals. Textural and chemical reactions between the REE fluorocarbonates provide insights into the mobility of rare-earth elements during fluid-rock interaction. The BIT complex is considered to be of potential economic interest for production of the rare-earth concentrates.