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OBJECTIVES: High rates of clinical acute rejection after kidney transplantation have been reported in people living with HIV (PLHIV), probably as a consequence of drug interactions. We therefore investigated the incidence of acute rejection within 6 months of transplantation in HIV-infected recipients treated with a protease-inhibitor-free raltegravir-based regimen. METHODS: The Agence Nationale de Recherche sur le Sida et les Hépatites Virales (ANRS) 153 TREVE (NCT01453192) study was a prospective multicentre single-arm trial in adult PLHIV awaiting kidney transplantation, with viral load < 50 HIV-1 RNA copies/mL, CD4 T-cell count > 200 cells/µL, and HIV-1 strains sensitive to raltegravir, aiming to demonstrate 6-month clinical acute rejection rates < 30%. Time to transplantation was compared with that for uninfected subjects matched for age, sex and registration date. RESULTS: In total, 61 participants were enrolled in the study, and 26 underwent kidney transplantation. Two participants experienced clinical acute rejection, corresponding to an estimated clinical acute rejection rate of 8% [95% confidence interval (CI) 2-24%] at 6 and 12 months post-transplantation. HIV infection remained under control in all but one participant, who temporarily stopped antiretroviral treatment. Median time to transplantation was longer in PLHIV than in controls (4.3 versus 2.8 years, respectively; P = 0.002) and was not influenced by blood group. CONCLUSIONS: Acute rejection rates were low after kidney transplantation in PLHIV treated with a raltegravir-based regimen. However, PLHIV have poorer access to transplantation than HIV-uninfected individuals after registration on the waiting list.
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Fármacos Anti-VIH/administración & dosificación , Rechazo de Injerto/epidemiología , Infecciones por VIH/tratamiento farmacológico , Raltegravir Potásico/administración & dosificación , Adulto , Fármacos Anti-VIH/uso terapéutico , Femenino , Infecciones por VIH/complicaciones , Infecciones por VIH/virología , VIH-1/efectos de los fármacos , Humanos , Incidencia , Trasplante de Riñón , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Raltegravir Potásico/uso terapéutico , Carga ViralRESUMEN
PURPOSE: To describe, in patients treated for infectious keratitis, the microorganisms identified and their antibiotic susceptibility over a period of 18 months. METHOD: Retrospective, descriptive, non-comparative study. Medical and biological data were extracted from the patients' file treated with strengthened antibiotic eye drops at Angers University Hospital between January 2015 and June 2016. The main elements noted were the bacteria involved and their susceptibility to antibiotics. Patients' visual acuity at the start and end of treatment was compared. RESULTS: Forty-eight patients were included. Almost one bacterium was identified in 31 patients, totalling 43 pathogens of 24 different species. The most frequently found microorganisms were Gram-positive cocci (55.8%), including Staphylococcus Aureus (14.0%) and Epidermidis (14.0%). All Gram-negative bacilli amounted to 30.2% of the identified bacteria, including 9.3% of Pseudomonas aeruginosa. None of the Gram-positive cocci were resistant to vancomycin and all Gram-negative bacilli were susceptible to ceftazidime and amikacin. Following treatment with at least one of the three antibiotic eye drops produced by our pharmacy (amikacin at 50mg/mL, ceftazidime at 50mg/mL and vancomycin at 25mg/mL), patients' visual acuity was significantly improved (P=0.043). CONCLUSION: The study helped identify the bacterial ecology of patients admitted for infectious keratitis. Among the bacteria identified, none were found to be resistant to any of the three strengthened antibiotic eye drops produced by the hospital pharmacy. These eye drops allowed for a rapid and effective treatment of patients and the improvement of their visual acuity before even identifying the bacteria.
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Antibacterianos/administración & dosificación , Antibacterianos/uso terapéutico , Infecciones Bacterianas del Ojo/tratamiento farmacológico , Queratitis/tratamiento farmacológico , Adulto , Anciano , Anciano de 80 o más Años , Antibacterianos/farmacología , Bacterias/efectos de los fármacos , Infecciones Bacterianas del Ojo/microbiología , Femenino , Humanos , Queratitis/microbiología , Masculino , Pruebas de Sensibilidad Microbiana , Persona de Mediana Edad , Soluciones Oftálmicas , Estudios Retrospectivos , Agudeza Visual , Adulto JovenRESUMEN
An analytical approach of the two-dimensional emissivity of a rough sea surface in the infrared band is presented. The emissivity characterizes the intrinsic radiation of the sea surface. Because the temperature measured by the infrared camera depends on the emissivity, the emissivity is a relevant parameter for retrieving the sea-surface temperature from remotely sensed radiometric measurements, such as from satellites. This theory is developed from the first-order geometrical-optics approximation and is based on recent research. The typical approach assumes that the slope in the upwind direction is greater than the slope in the crosswind direction, involving the use of a one-dimensional shadowing function with the observed surface assumed to be infinite. We introduce the two-dimensional shadowing function and the surface observation length parameters that are included in the modeling of the two-dimensional emissivity.
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Extended Hückel and density functional calculations carried out on 128-MVE Cu(8)(dithiolato)(6) edge-bridged cubic clusters indicate that their stability is mainly driven by the chelating effect of the ligands, which provide a stable 16-electron configuration to the approximately trigonal planar metal centers. Nevertheless, a weak but significant d(10)-d(10) bonding interaction is present which is rather independent from the dithiolato bite effect. The metal centers have a nonbonding 4p(z)() vacant AO pointing to the center of the cube available for bonding to an encapsulated atom. The electronic closed-shell requirement is satisfied for the 136-MVE and 140-MVE counts, respectively, when a main-group atom or a transition-metal atom is incorporated in the middle of the cube. The bonding within these dithiolato compounds is compared to other edge-bridged M(8) cubic clusters. In particular, it is shown that clusters of higher nuclearity but containing an M(8) cubic core are related to the dithiolato species. Indeed, their outer metal atoms can be considered as belonging to the ligand shell, interacting with the M(8) cube in a way similar to the dithiolato ligands in the Cu(8) species.
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Based on sequencing data and results obtained from applying a tailored mismatch polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) analysis, we report that the G allele of the mitochondrial DNA (mtDNA) polymorphism at nucleotide position 11719 is associated with the European mtDNA haplogroup cluster HV, and that 11719A is therefore the ancestral allele.
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ADN Mitocondrial/genética , Haplotipos/genética , Polimorfismo Genético , Dinamarca , Marcadores Genéticos , Humanos , Atrofias Ópticas Hereditarias/genéticaRESUMEN
The Eskimo-Aleut language phylum is distributed from coastal Siberia across Alaska and Canada to Greenland and is well distinguished from the neighboring Na Dene languages. Genetically, however, the distinction between Na Dene and Eskimo-Aleut speakers is less clear. In order to improve the genetic characterization of Eskimos in general and Greenlanders in particular, we have sequenced hypervariable segment I (HVS-I) of the mitochondrial DNA (mtDNA) control region and typed relevant RFLP sites in the mtDNA of 82 Eskimos from Greenland. A comparison of our data with published sequences demonstrates major mtDNA types shared between Na Dene and Eskimo, indicating a common Beringian history within the Holocene. We further confirm the presence of an Eskimo-specific mtDNA subgroup characterized by nucleotide position 16265G within mtDNA group A2. This subgroup is found in all Eskimo groups analyzed so far and is estimated to have originated <3,000 years ago. A founder analysis of all Eskimo and Chukchi A2 types indicates that the Siberian and Greenland ancestral mtDNA pools separated around the time when the Neo-Eskimo culture emerged. The Greenland mtDNA types are a subset of the Alaskan mtDNA variation: they lack the groups D2 and D3 found in Siberia and Alaska and are exclusively A2 but at the same time lack the A2 root type. The data are in agreement with the view that the present Greenland Eskimos essentially descend from Alaskan Neo-Eskimos. European mtDNA types are absent in our Eskimo sample.
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ADN Mitocondrial/genética , Emigración e Inmigración , Variación Genética/genética , Inuk/genética , Filogenia , Alaska/etnología , Secuencia de Bases , Efecto Fundador , Geografía , Groenlandia/etnología , Humanos , Cinética , Lingüística , Mutagénesis/genética , Polimorfismo de Longitud del Fragmento de Restricción , Tamaño de la Muestra , Factores de TiempoRESUMEN
The authors report a case of bacterial endocarditis from unidentified bacteria, responsible for a rupture of chordae of the mitral valve in a 4 month-old infant with a previously normal heart. Bidimensional echocardiography led to diagnosis. The importance of the mitral loss thus created made a mitral plasty necessary with cardiopulmonary by-pass at age 2 years. Ultrasonographic data were then confirmed. Postoperative result was excellent. The features of acute bacterial endocarditis in infancy are reviewed.
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Endocarditis Bacteriana/complicaciones , Válvula Mitral , Enfermedad Aguda , Ecocardiografía , Electrocardiografía , Endocarditis Bacteriana/diagnóstico , Femenino , Enfermedades de las Válvulas Cardíacas/diagnóstico , Enfermedades de las Válvulas Cardíacas/etiología , Prótesis Valvulares Cardíacas , Humanos , Lactante , Válvula Mitral/cirugíaRESUMEN
The synthesis by arc-melting techniques, the single-crystal X-ray structure, and the theoretical analysis of Gd4B3C4 are reported. It crystallizes in the triclinic space group P1 with a = 3.637(2) A, b = 3.674(2) A, c = 11.859(5) A, alpha = 93.34(5) degrees, beta = 96.77(5) degrees, gamma = 90.24(5) degrees, and Z = 1. In this structure, the boron and carbon atoms form two different types of nonmetal arrangements: 1-D (BC)infinity branched chains and finite (0-D) linear CBC "molecular" units. Gd4B3C4 is the first characterized member of the rare earth metal borocarbide series in which both 1-D and "molecular" 0-D nonmetal atom systems coexist. From the structural and theoretical analysis, the following formal charge distribution can be proposed within the ionic limit: (Gd3+)4(BC2(5-)(BC3-)2.e-. Tight-binding calculations suggest that the excess electron in the ionic limit is mainly localized on the Gd atoms (at the bottom of the 5d band), while LAPW calculations favor its localization on the (BC)infinity chain. The bonding within this compound is fully analyzed and compared to other members of the rare earth metal borocarbide series.
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The compounds Cp*Fe(dppe)X ([Fe]X) and the corresponding cation radicals [Fe*]X*+ are available for the series X = F, Cl, Br, I, H, CH3. This has allowed for a detailed investigation of the dependence of the nature of Fe-X bonding on the identity of X and the oxidation state (charge) of the complex. Cyclic voltammetry demonstrates that the electrode potentials for the [Fe]X0/+ couples decrease in the order I > Br > Cl > H > F > CH3. An "inverse halide order" is seen, in which the most electronegative X leads to the most easily oxidized complex. This suggests that F is the best donor among the halides. The halide trend is also reflected in NMR spectroscopic data. Mössbauer spectroscopy data also suggest that the F ligand is a strong donor (relative to H and CH3) in [Fe*]X*+. DFT calculations on CpFe(dpe)X ([Fe]X) model complexes nicely reproduce the trend in the electrode potentials for the [Fe*]X0/+ couples. Analysis of the theoretical data within the halogen series indicates that the energy of the [Fe]X HOMO does not correlate with the extent of its Fe(d(pi))-X(p(pi)) antibonding character, which varies in the order I > Br > Cl > F, but rather depends on the destabilizing electrostatic effect caused by X. This effect varies in the order F > Cl > Br > I. A thermochemical cycle that incorporates the [Fe*]X0/+ and [Fe*]0/+ electrode potentials was used to investigate the effect of the oxidation state of the complex on the homolytic bond dissociation energy (BDEhom), defined for the processes Fe-X --> Fe* + X* and Fe-X*+ --> Fe*+ + X*. For all X, it was found that a one-electron oxidation leads to a weakening of the Fe-X bond. This trend was reproduced by the DFT calculations. On the other hand, IR nu(Fe-X) spectroscopy data showed an increase in the stretching frequencies for X = H and Cl upon oxidation. X-ray crystallographic data showed a shortening of the Fe-Cl bond upon oxidation. The trends in IR and Fe-Cl bond distances were reproduced in the DFT calculations. The combined data therefore suggest that oxidation leads to weaker, but shorter, Fe-X bonds. A second thermochemical cycle was applied to investigate the effect of the one-electron oxidation on the heterolytic bond dissociation energies (BDEhet), defined for the processes Fe-X --> Fe+ + X- and Fe-X*+ --> Fe2+ + X-. In this case, the oxidation led to bond strengthening in all cases. The computed BDE values have been analyzed within Ziegler's transition state methodology and decomposed into two components, one electrostatic and one covalent, describing the interaction between the unrelaxed fragments. In all the computed BDEhom and BDEhet values of the [Fe]X models the electrostatic component is important. This helps to understand their respective variations upon oxidation.