959 resultados para 1.5 GPA
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AIMS: To describe the procedural performance and 30-day outcomes following implantation using the 18 Fr CoreValve Revalving System (CRS) as part of the multicentre, expanded evaluation registry, 1-year after obtaining CE mark approval. METHODS AND RESULTS: Patients with symptomatic severe aortic stenosis and logistic Euroscore > or =15%, or age > or =75 years, or age > or =65 years associated with pre-defined risk factors, and for whom a physician proctor and a clinical specialist were in attendance during the implantation and who collected the clinical data, were included. From April 2007, to April 2008, 646 patients with a mean age of 81 +/- 6.6 years, mean aortic valve area 0.6 +/- 0.2 cm2, and logistic EuroSCORE of 23.1 +/- 13.8% were recruited. After valve implantation, the mean transaortic valve gradient decreased from 49.4 +/- 13.9 to 3 +/- 2 mmHg. All patients had paravalvular aortic regurgitation < or = grade 2. The rate of procedural success was 97%. The procedural mortality rate was 1.5%. At 30 days, the all-cause mortality rate (i.e, including procedural) was 8% and the combined rate of death, stroke and myocardial infarction was 9.3%. CONCLUSIONS: The results of this study demonstrate the high rate of procedural success and a low 30-day mortality in a large cohort of high-risk patients undergoing transcatheter aortic valve implantation (TAVI) with the CRS.
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OBJECT: In this study, the authors prospectively evaluated long-term psychosocial and neurocognitive performance in patients suffering from nonaneurysmal, nontraumatic subarachnoid hemorrhage (SAH) and investigated the association between the APOE-epsilon4 genotype and outcome in these patients. METHODS: All patients admitted to the authors' institution between January 2001 and January 2003 with spontaneous nonaneurysmal SAH were prospectively examined (mean follow-up 59.8 months). The APOE genotype was determined in all patients by polymerase chain reaction from a blood sample. Of the 30 patients included in this study, 11 were carriers of the epsilon4 allele. RESULTS: All patients showed a good recovery and regained full independence with no persisting neurological deficits. The patients with the epsilon4 allele, however, scored significantly higher on the Beck Depression Inventory (22.1 +/- 6.3 vs 14.1 +/- 5.1). At follow-up, depression was more persistent in the group with the epsilon4 allele compared with the group that lacked the allele. This finding reached statistical significance (p < 0.05). Selective attention was impaired in all patients during the first year of follow-up, with an earlier recovery noted in the patients without the epsilon4 allele. Moreover, there was a tendency toward a linear relationship between the Beck Depression Inventory and the d2 Test of Attention. Two patients who carried the epsilon4 allele did not return to their employment even after 5 years. CONCLUSIONS: The findings in this study suggest that the APOE genotypes may be associated with the psychosocial and neurocognitive performance after spontaneous nonaneurysmal SAH, even in the absence of neurological impairment. Physicians should consider patient genotype in assessing the long-term consequences of nonaneurysmal SAH.
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To investigate mechanisms by which angiotensin converting enzyme (ACE)-inhibition increases insulin sensitivity, spontaneously hypertensive (SH) rats were treated with or without ramipril (1 mg/kg per day) for 12 weeks. Insulin binding and protein levels of insulin receptor substrate-1 (IRS-1), p85-subunit of phosphatidylinositol 3'-kinase (p85) and Src homology 2 domain-containing phosphatase-2 (SHP2) were then determined in hindlimb muscle and liver. Additionally, protein tyrosine phosphatase (PTPase) activities towards immobilized phosphorylated insulin receptor or phosphorylated IRS-1 of membrane (MF) and cytosolic fractions (CF) of these tissues were measured. Ramipril treatment increased IRS-1-protein content in muscle by 31+/-9% (P<0.05). No effects were observed on IRS-1 content in liver or on insulin binding or protein expression of p85 or SHP2 in both tissues. Ramipril treatment also increased dephosphorylation of insulin receptor by muscle CF (22.0+/-1.0%/60 min compared to 16.8+/-1.5%/60 min; P<0.05), and of IRS-1 by liver MF (37.2+/-1.7%/7.5 min compared to 33.8+/-1.7%/7.5 min; P<0.05) and CF (36.8+/-1.0%/7.5 min compared to 33.2+/-1.0%/7.5 min; P<0.05). We conclude that the observed effects of ACE-inhibition by ramipril on the protein expression of IRS-1 and on PTPase activity might contribute to its effect on insulin sensitivity.
Identification of small Sca-1(+), Lin(-), CD45(-) multipotential cells in the neonatal murine retina
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OBJECTIVE: Bone marrow contains a subset of stem cells that give rise to nonhematopoietic lineages. These nonhematopoietic stem cells appear heterogeneous and contain cells committed to mesenchymal and endothelial lineages, as well as more primitive multipotential cells resembling progenitors of germ cells and very small embryonic/epiblast-like stem cells (VSELs). Nonhematopoietic stem cells can be mobilized from the bone marrow in response to tissue injury, and cells with similar properties have been found in cord blood and normal adult organs. However, the relationship between bone marrow cells and these adult organ stem cells is still unclear. The differentiation potential of some adult stem cells is organ-restricted, but other populations appear to retain multipotential capacity. MATERIALS AND METHODS: A population of small Sca-1(+), lineage-negative (Lin(-)), CD45(-) cells resembling VSELs were isolated from neonatal mouse retina by cell sorting. Differentiation of the cells in culture was achieved by exposure to embryonic stem cell differentiation protocols. RESULTS: VSEL-like cells comprise 1.5% of the neonatal mouse retina. They remain quiescent during retinal differentiation, and thus they do not contribute to normal retinal development. However, they display eye cell differentiation potential in culture and they are also multipotential and can give rise to cells representative of all three embryonic layers. CONCLUSIONS: The neonatal retina is an abundant postnatal source of multipotential VSEL-like cells that can differentiate in culture into a variety of lineages.
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BACKGROUND: Prognostic models for children starting antiretroviral therapy (ART) in Africa are lacking. We developed models to estimate the probability of death during the first year receiving ART in Southern Africa. METHODS: We analyzed data from children ≤10 years old who started ART in Malawi, South Africa, Zambia or Zimbabwe from 2004-2010. Children lost to follow-up or transferred were excluded. The primary outcome was all-cause mortality in the first year of ART. We used Weibull survival models to construct two prognostic models: one with CD4%, age, WHO clinical stage, weight-for-age z-score (WAZ) and anemia and one without CD4%, because it is not routinely measured in many programs. We used multiple imputation to account for missing data. RESULTS: Among 12655 children, 877 (6.9%) died in the first year of ART. 1780 children were lost to follow-up/transferred and excluded from main analyses; 10875 children were included. With the CD4% model probability of death at 1 year ranged from 1.8% (95% CI: 1.5-2.3) in children 5-10 years with CD4% ≥10%, WHO stage I/II, WAZ ≥-2 and without severe anemia to 46.3% (95% CI: 38.2-55.2) in children <1 year with CD4% <5%, stage III/IV, WAZ< -3 and severe anemia. The corresponding range for the model without CD4% was 2.2% (95% CI: 1.8-2.7) to 33.4% (95% CI: 28.2-39.3). Agreement between predicted and observed mortality was good (C-statistics=0.753 and 0.745 for models with and without CD4% respectively). CONCLUSION: These models may be useful to counsel children/caregivers, for program planning and to assess program outcomes after allowing for differences in patient disease severity characteristics.
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Purpose The better understanding of vertebral mechanical properties can help to improve the diagnosis of vertebral fractures. As the bone mechanical competence depends not only from bone mineral density (BMD) but also from bone quality, the goal of the present study was to investigate the anisotropic indentation moduli of the different sub-structures of the healthy human vertebral body and spondylophytes by means of microindentation. Methods Six human vertebral bodies and five osteophytes (spondylophytes) were collected and prepared for microindentation test. In particular, indentations were performed on bone structural units of the cortical shell (along axial, circumferential and radial directions), of the endplates (along the anterio-posterior and lateral directions), of the trabecular bone (along the axial and transverse directions) and of the spondylophytes (along the axial direction). A total of 3164 indentations down to a maximum depth of 2.5 µm were performed and the indentation modulus was computed for each measurement. Results The cortical shell showed an orthotropic behavior (indentation modulus, Ei, higher if measured along the axial direction, 14.6±2.8 GPa, compared to the circumferential one, 12.3±3.5 GPa, and radial one, 8.3±3.1 GPa). Moreover, the cortical endplates (similar Ei along the antero-posterior, 13.0±2.9 GPa, and along the lateral, 12.0±3.0 GPa, directions) and the trabecular bone (Ei= 13.7±3.4 GPa along the axial direction versus Ei=10.9±3.7 GPa along the transverse one) showed transversal isotropy behavior. Furthermore, the spondylophytes showed the lower mechanical properties measured along the axial direction (Ei=10.5±3.3 GPa). Conclusions The original results presented in this study improve our understanding of vertebral biomechanics and can be helpful to define the material properties of the vertebral substructures in computational models such as FE analysis.
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The Stak massif, northern Pakistan, is a newly recognized occurrence of eclogite formed by the subduction of the northern margin of the Indian continent in the northwest Himalaya. Although this unit was extensively retrogressed during the Himalayan collision, records of the high-pressure (HP) event as well as a continuous pressure-temperature (P-T) path were assessed from a single thin section using a new multiequilibrium method. This method uses microprobe X-ray compositional maps of garnet and omphacitic pyroxene followed by calculations of ∼200,000 P-T estimates using appropriate thermobarometers. The Stak eclogite underwent prograde metamorphism, increasing from 650 °C and 2.4 GPa to the peak conditions of 750 °C and 2.5 GPa, then retrogressed to 700–650 °C and 1.6–0.9 GPa under amphibolite-facies conditions. The estimated peak metamorphic conditions and P-T path are similar to those of the Kaghan and Tso Morari high- to ultrahigh-pressure (HP-UHP) massifs. We propose that these three massifs define a large HP to UHP province in the northwest Himalaya, comparable to the Dabie-Sulu province in China and the Western Gneiss Region in Norway.
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Experience with anidulafungin against Candida krusei is limited. Immunosuppressed mice were injected with 1.3 x 10(7) to 1.5 x 10(7) CFU of C. krusei. Animals were treated with saline, 40 mg/kg fluconazole, 1 mg/kg amphotericin B, or 10 and 20 mg/kg anidulafungin for 5 days. Anidulafungin improved survival and significantly reduced the number of CFU/g in kidneys and serum beta-glucan levels.
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The neutral bis ((pivaloyloxy)methyl) (PIV$\sb2\rbrack$ derivatives of FdUMP, ddUMP, and AZTMP were synthesized as potential membrane-permeable prodrugs of FdUMP, ddUMP, and AZTMP. These compounds were designed to enter cells by passive diffusion and revert to the parent nucleotides after removal of the PIV groups by hydrolytic enzymes. These prodrugs were prepared by condensation of FUdR, ddU, and AZT with PIV$\sb2$ phosphate in the presence of triphenylphosphine and diethyl azodicarboxylate (the Mitsunobo reagent). PIV$\sb2$-FdUMP, PIV$\sb2$-ddUMP, and PIV$\sb2$-AZTMP were stable in the pH range 1.0-4.0 (t$\sb{1/2} = {>}$100 h). They were also fairly stable at pH 7.4 (t$\sb{1/2} = {>}$40 h). In 0.05 M NaOH solution, however, they were rapidly degraded (t$\sb{1/2} < 2$ min). In the presence hog liver carboxylate esterase, they were converted quantitatively to the corresponding phosphodiesters, PIV$\sb1$-FdUMP, PIV$\sb1$-ddUMP, and PIV$\sb1$-AZTMP; after 24 h incubation, only trace amounts of FdUMP, ddUMP, and AZTMP (1-5%) were observed indicating that the PIV$\sb1$ compounds were poor substrates for the enzyme. In human plasma, the PIV$\sb2$ compounds were rapidly degraded with half-lives of less than 5 min. The rate of degradation of the PIV$\sb2$ compounds in the presence of phosphodiesterase I was the same as that in buffer controls, indicating that they were not substrates for this enzyme. In the presence of phosphodiesterase I, PIV$\sb1$-FdUMP, PIV$\sb1$-ddUMP, and PIV$\sb1$-AZTMP were converted quantitatively to FdUMP, ddUMP, and AZTMP.^ PIV$\sb2$-ddUMP and PIV$\sb2$-AZTMP were effective at controlling HIV type 1 infection in MT-4 and CEM tk$\sp-$ cells in culture. Mechanistic studies demonstrated that PIV$\sb2$-ddUMP and PIV$\sb2$-AZTMP were taken up by the cells and converted to ddUTP and AZTTP, both potent inhibitors of HIV reverse transcriptase. However, a potential shortcoming of PIV$\sb2$-ddUMP and PIV$\sb2$-AZTMP as clinical therapeutic agents is that they are rapidly degraded (t$\sb{1/2}$ = approx. 4 minutes) in human plasma by carboxylate esterases. To circumvent this limitation, chemically-labile nucleotide prodrugs and liposome-encapsulated nucleotide prodrugs were investigated. In the former approach, the protective groups bis(N, N-(dimethyl)carbamoyloxymethyl) (DM$\sb2$) and bis (N-(piperidino)carbamoyloxymethyl) (DP$\sb2$) were used to synthesize DM$\sb2$-ddUMP and DP$\sb2$-ddUMP, respectively. In aqueous buffers (pH range 1.0-9.0) these compounds were degraded with half-lives of 3 to 4 h. They had similar half-lives in human plasma demonstrating that they were resistant to esterase-mediated cleavage. However, neither compound gave rise to significant concentrations of ddUMP in CEM or CEM tk$\sp-$ cells. In the liposome-encapsulated nucleotide prodrug approach, three different liposomal formulations of PIV$\sb2$-ddUMP (L-PIV$\sb2$-ddUMP) were investigated. The half-lifes of these L-PIV$\sb2$-ddUMP preparations in human plasma were 2 h compared with 4 min for the free drug. The preparations were more effective at controlling HIV-1 infection than free PIV$\sb2$-ddUMP in human T cells in culture. Collectively, these data indicate that PIV$\sb2$-FdUMP, PIV$\sb2$-ddUMP, and PIV$\sb2$-AZTMP are effective membrane-permeable prodrugs of FdUMP, ddUMP, and AZTMP. ^
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PURPOSE To evaluate and compare crestal bone level changes and peri-implant status of implant-supported reconstructions in edentulous and partially dentate patients after a minimum of 5 years of loading. MATERIALS AND METHODS All patients who received a self-tapping implant with a microstructured surface during the years 2003 and 2004 at the Department of Prosthodontics, University of Bern, were included in this study. The implant restorations comprised fixed and removable prostheses for partially and completely edentulous patients. Radiographs were taken immediately after surgery, at impression making, and 1 and 5 years after loading. Crestal bone level (BIC) was measured from the implant shoulder to the first bone contact, and changes were calculated over time (ΔBIC). The associations between pocket depth, bleeding on probing (BOP), and ΔBIC were assessed. RESULTS Sixty-one implants were placed in 20 patients (mean age, 62 ± 7 years). At the 5-year follow-up, 19 patients with 58 implants were available. Implant survival was 98.4% (one early failure; one patient died). The average ΔBIC between surgery and 5-year follow-up was 1.5 ± 0.9 mm and 1.1 ± 0.6 mm for edentulous and partially dentate patients, respectively. Most bone resorption (50%, 0.7 mm) occurred during the first 3 months (osseointegration) and within the first year of loading (21%, 0.3 mm). Mean annual bone loss during the 5 years of loading was < 0.12 mm. Mean pocket depth was 2.6 ± 0.7 mm. Seventeen percent of the implant sites displayed BOP; the frequency was significantly higher in women. None of the variables were significantly associated with crestal bone loss. CONCLUSION Crestal bone loss after 5 years was within the normal range, without a significant difference between edentulous and partially dentate patients. In the short term, this implant system can be used successfully for various prosthetic indications.
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OBJECTIVES Many paediatric antiretroviral therapy (ART) programmes in Southern Africa rely on CD4⁺ to monitor ART. We assessed the benefit of replacing CD4⁺ by viral load monitoring. DESIGN A mathematical modelling study. METHODS A simulation model of HIV progression over 5 years in children on ART, parameterized by data from seven South African cohorts. We simulated treatment programmes with 6-monthly CD4⁺ or 6- or 12-monthly viral load monitoring. We compared mortality, second-line ART use, immunological failure and time spent on failing ART. In further analyses, we varied the rate of virological failure, and assumed that the rate is higher with CD4⁺ than with viral load monitoring. RESULTS About 7% of children were predicted to die within 5 years, independent of the monitoring strategy. Compared with CD4⁺ monitoring, 12-monthly viral load monitoring reduced the 5-year risk of immunological failure from 1.6 to 1.0% and the mean time spent on failing ART from 6.6 to 3.6 months; 1% of children with CD4⁺ compared with 12% with viral load monitoring switched to second-line ART. Differences became larger when assuming higher rates of virological failure. When assuming higher virological failure rates with CD4⁺ than with viral load monitoring, up to 4.2% of children with CD4⁺ compared with 1.5% with viral load monitoring experienced immunological failure; the mean time spent on failing ART was 27.3 months with CD4⁺ monitoring and 6.0 months with viral load monitoring. Conclusion: Viral load monitoring did not affect 5-year mortality, but reduced time on failing ART, improved immunological response and increased switching to second-line ART.
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Measurements of two-particle correlation functions and the first five azimuthal harmonics, v 1 to v 5 , are presented, using 28 nb −1 of p+Pb collisions at a nucleon-nucleon center-of-mass energy of √s NN=5.02 TeV measured with the ATLAS detector at the LHC. Significant long-range “ridgelike” correlations are observed for pairs with small relative azimuthal angle (|Δϕ|<π/3 ) and back-to-back pairs (|Δϕ|>2π/3 ) over the transverse momentum range 0.4
1.5 –2.0 GeV and then increase to about 0.1 for p T >4 GeV. The v 2 (p T ) , v 3 (p T ) , and v 4 (p T ) are compared to the v n coefficients in Pb+Pb collisions at √s NN=2.76 TeV with similar event multiplicities. Reasonable agreement is observed after accounting for the difference in the average p T of particles produced in the two collision systems.
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Convergent plate margins typically experience a transition from subduction to collision dynamics as massive continental blocks enter the subduction channel. Studies of high-pressure rocks indicate that tectonic fragments are rapidly exhumed from eclogite facies to midcrustal levels, but the details of such dynamics are controversial.To understand the dynamics of a subduction channel we report the results of a petrochronological study from the central Sesia Zone, a key element of the internalWestern Alps.This comprises two polymetamorphic basement complexes (Eclogitic Micaschist Complex and Gneiss Minuti Complex) and a thin, dismembered cover sequence (Scalaro Unit) associated with pre-Alpine metagabbros and metasediments (Bonze Unit). Structurally controlled samples from three of these units (Eclogitic Micaschist Complex and Scalaro-Bonze Units) yield unequivocal petrological and geochronological evidence of two distinct high-pressure stages. Ages (U-Th-Pb) of growth zones in accessory allanite and zircon, combined with inclusion and textural relationships, can be tied to the multi-stage evolution of single samples.Two independent tectono-metamorphic ‘slices’ showing a coherent metamorphic evolution during a given time interval have been recognized: the Fondo slice (which includes Scalaro and Bonze rocks) and the Druer slice (belonging to the Eclogitic Micaschist Complex).The new data indicate separate stages of deformation at eclogite-facies conditions for each recognized independent kilometer-sized tectono-metamorphic slice, between ~85 and 60 Ma, with evidence of intermittent decompression (∆P~0.5 GPa) within only the Fondo slice. The evolution path of the Druer slice indicates a different P-T-time evolution with prolonged eclogite-facies metamorphism between ~85 and 75Ma. Our approach, combining structural, petrological and geochronological techniques, yields field-based constraints on the duration and rates of dynamics within a subduction channel.