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1.
Sci Data ; 11(1): 81, 2024 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-38233447

RESUMO

Shotgun metagenomic sequencing comprehensively samples the DNA of a microbial sample. Choosing the best bioinformatics processing package can be daunting due to the wide variety of tools available. Here, we assessed publicly available shotgun metagenomics processing packages/pipelines including bioBakery, Just a Microbiology System (JAMS), Whole metaGenome Sequence Assembly V2 (WGSA2), and Woltka using 19 publicly available mock community samples and a set of five constructed pathogenic gut microbiome samples. Also included is a workflow for labelling bacterial scientific names with NCBI taxonomy identifiers for better resolution in assessing results. The Aitchison distance, a sensitivity metric, and total False Positive Relative Abundance were used for accuracy assessments for all pipelines and mock samples. Overall, bioBakery4 performed the best with most of the accuracy metrics, while JAMS and WGSA2, had the highest sensitivities. Furthermore, bioBakery is commonly used and only requires a basic knowledge of command line usage. This work provides an unbiased assessment of shotgun metagenomics packages and presents results assessing the performance of the packages using mock community sequence data.


Assuntos
Microbioma Gastrointestinal , Metagenoma , Bactérias/genética , Metagenômica/métodos , Análise de Sequência de DNA/métodos
2.
HIV Med ; 24(9): 1013-1019, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37194419

RESUMO

BACKGROUND: Dolutegravir (DTG) plus lamivudine (3TC) has proven highly efficacious as a switching strategy in virologically suppressed people with HIV (PWH). As this strategy was introduced relatively recently, real-world, long-term durability studies are lacking. METHODS: We performed a retrospective review of treatment-experienced patients who started DTG + 3TC in a cohort of PWH. HIV-RNA <50 copies/mL was analysed at 144 weeks in an intention-to-treat (ITT) analysis (missing = failure) and a per-protocol (PP) analysis (patients with missing data or changes for reasons other than virological failure were excluded). RESULTS: The study population comprised 358 PWH (19% women). Median age and time with HIV infection were 51.7 and 13.4 years, respectively. The median number of previous antiretroviral combinations was three. Previous virological failure was reported in 27.1% of patients, and the M184V resistance mutation was detected in 17 patients. At 144 weeks, the percentage of individuals with HIV-RNA <50 copies/mL was 77.4% (277/358) in the ITT analysis and 95.5% (277/290) in the PP analysis. A total of 68 participants were excluded from the PP analysis (data missing, 25, discontinuation due to toxicity, 19; other, 16; death, 8). Two people with virological failure selected resistance-associated mutations (M184V and M184V + R263K). HIV-RNA remained undetectable in 17 patients with a previous history of the M184V mutation. CONCLUSION: Our results confirm the real-world, long-term efficacy, tolerability and high genetic barrier of DTG + 3TC in treatment-experienced PWH. Although scarce, mutations causing resistance to nucleosides and integrase can emerge.


Assuntos
Fármacos Anti-HIV , Infecções por HIV , Humanos , Feminino , Masculino , Lamivudina/uso terapêutico , Infecções por HIV/tratamento farmacológico , Fármacos Anti-HIV/uso terapêutico , Oxazinas/uso terapêutico , Compostos Heterocíclicos com 3 Anéis/efeitos adversos , RNA/uso terapêutico
3.
Front Pharmacol ; 13: 905126, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36110512

RESUMO

Background and aims: Nonalcoholic fatty liver disease (NAFLD) is a common cause of liver damage in people living with HIV (PLWHIV). Several studies have investigated candidate genes for susceptibility to NAFLD and to steatohepatitis. PNPLA3, TM6SF2, and MBOAT7-TMC4 have been reported to be associated with elevated ALT levels and the histologic parameters of nonalcoholic steatohepatitis and severity of fibrosis. Our objective was to analyze the relationship between PNPLA3, TM6SF2, and MBOAT7-TMC4 and steatosis, steatohepatitis, and liver fibrosis in PLWHIV with NAFLD. Method: A cohort of PLWHIV with persistently elevated aminotransferase levels and suspected NAFLD who underwent liver biopsy and determination of genetic variants was assessed at two large centers in Spain. All participants included in the current study were genotyped for rs738409 (PNPLA3), rs58542926 (TM6SF2), and rs641738 (MBOAT7-TMC4). Results: The study population comprised PLWHIV who were on stable antiretroviral therapy [7.7% women; median age, 49.3 years (44-53.4)]. The median CD4 count was 829 (650-980), 60% had metabolic syndrome, and 18.5% were diabetic. The median BMI was 28.9 (25.5-30.8). Patients with liver steatosis (any grade) vs. nonsteatosis tended to harbor the PNPLA3 G allele variant [57.6% vs. 16.7% (p = 0.09)], but not TM6SF2 or MBOAT7-TMC4 variants. However, those with steatohepatitis vs. nonsteatohepatitis significantly more frequently had the PNPLA3 G allele variant [69.4% vs. 39.1% (p < 0.05)] and the MBOAT7-TMC4 A allele variant [75% vs. 42% (p < 0.05)]. In our cohort, the TM6SF2 gene variant was not associated with steatosis or steatohepatitis. The PNPLA3 G allele variant was associated with steatohepatitis [OR 4.9 (1.3-18); p 0.02] and liver fibrosis [OR 4.3 (1.1-17.4); p 0.04], and the MBOAT7-TMC4 A allele variant was associated with steatohepatitis [OR 6.6 (1.6-27.6); p 0.01]. Conclusion: The PNPLA3 G allele variant and MBOAT7-TMC4 A allele variant were associated with steatohepatitis and liver fibrosis in PLWHIV with persistently elevated aminotransferases and NAFLD. We recommend routine genotyping for PNPLA3 and MBOAT7-TMC4 in PLWHIV with NAFLD to identify those at higher risk of progression.

4.
Open Forum Infect Dis ; 9(7): ofac279, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35873289

RESUMO

Background: Nonalcoholic fatty liver disease (NAFLD) is a major nonacquired immune deficiency syndrome-defining condition for persons with human immunodeficiency virus (PWH). We aimed to validate noninvasive tests for the diagnosis of NAFLD in PWH. Methods: This is a cross-sectional study of PWH on stable antiretroviral therapy with persistently elevated transaminases and no known liver disease. The area under the receiver operating characteristic curve (AUROC) was calculated to compare the diagnostic accuracy of liver biopsy with abdominal ultrasound, transient elastography (TE) (including controlled attenuation parameter [CAP]), and noninvasive markers of steatosis (triglyceride and glucose index [TyG], hepatic steatosis index [HSI], fatty liver index [FLI]) and fibrosis ([FIB]-4, aminotransferase-to-platelet ratio index [APRI], NAFLD fibrosis score). We developed a diagnostic algorithm with serial combinations of markers. Results: Of 146 patients with increased transaminase levels, 69 underwent liver biopsy (90% steatosis, 61% steatohepatitis, and 4% F ≥3). The AUROC for steatosis was as follows: ultrasound, 0.90 (0.75-1); CAP, 0.94 (0.88-1); FLI, 0.81 (0.58-1); HSI, 0.74 (0.62-0.87); and TyG, 0.75 (0.49-1). For liver fibrosis ≥F3, the AUROC for TE, APRI, FIB-4, and NAFLD fibrosis score was 0.92 (0.82-1), 0.96 (0.90-1), 0.97 (0.93-1), and 0.85 (0.68-1). Optimal diagnostic performance for liver steatosis was for 2 noninvasive combined models of tests with TyG and FLI/HSI as the first tests and ultrasound or CAP as the second tests: AUROC = 0.99 (0.97-1, P < .001) and 0.92 (0.77-1, P < .001). Conclusions: Ultrasound and CAP performed best in diagnosing liver steatosis, and FLI, TyG, and HSI performed well. We propose an easy-to-implement algorithm with TyG or FLI as the first test and ultrasound or CAP as the second test to accurately diagnose or exclude NAFLD.

5.
Cells Dev ; 170: 203793, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35649504

RESUMO

Alopecia is a non-specific term for hair loss clinically diagnosed by the hair loss pattern and histological analysis of patient scalp biopsies. The immune-mediated alopecia subtypes, including alopecia areata, lichen planopilaris, frontal fibrosing alopecia, and central centrifugal cicatricial alopecia, are common, significant forms of alopecia subtypes. For example, alopecia areata is the most common autoimmune disease with a lifetime incidence of approximately 2% of the world's population. In this perspective, we discuss major results from studies of immune-mediated alopecia subtypes. These studies suggest the key event in disease onset as the collapse in immune privilege, which alters the hair follicle microenvironment, e.g., upregulation of major histocompatibility complex molecules and increase of cytokine production, and results in immune cell infiltration, inflammatory responses, and damage of hair follicles. We note that previous studies have established that the hair follicle has a complex mechanical microenvironment, which may regulate the function of not only tissue cells but also immune cell infiltrates. This suggests a potential for mechanobiology to contribute to alopecia research by adding new methods, new approaches, and new ways of thinking, which is missing in the existing literature. To fill this a gap in the alopecia research space, we develop a mechanobiological hypothesis that alterations in the hair follicle microenvironment, specifically in the mechanically responsive tissues and cells, partially due to loss of immune privilege, may be contributors to disease pathology. We further focus our discussion on the potential for applying mechanoimmunology to the study of T cell infiltrates in the hair follicle, as they are considered primary contributors to alopecia pathology. To establish the connection between the mechanoimmunological hypothesis and immune-mediated alopecia subtypes, we discuss what is known about the role of T cells in immune-mediated alopecia subtypes, using the most extensively studied AA as our model.


Assuntos
Alopecia em Áreas , Líquen Plano , Biofísica , Folículo Piloso , Humanos , Líquen Plano/patologia
6.
Trop Anim Health Prod ; 53(5): 448, 2021 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-34533661

RESUMO

This study aimed to evaluate the effect of two marker dosage frequencies and two spot fecal sampling frequencies on the variability of fecal output estimation and fecal recovery rate in grazing Blanco Orejinegro (BON) steers with chromium (Cr) or titanium (Ti) as external markers. Four steers (230.5 ± 14.4 kg BW) were used in a 4 × 4 Latin square design in a split-plot arrangement with two markers: Cr or Ti, two marker dosage frequencies: 10.0 g Cr2O3 or TiO2/steer once daily (DF1) or 5.0 g Cr2O3 or TiO2/steer twice daily (DF2), and two fecal sampling frequencies: spot sampling once daily (SF1) or spot sampling twice daily (SF2). Steers were equipped with fecal collection bags to evaluate the actual fecal output (FOR). Fecal marker concentration (FMC) was affected by marker dosage frequency × fecal sampling frequency interaction (P = 0.032): SF1DF1 allowed higher FMC (2.26 g/kg DM) than SF2DF1 (1.95 g/kg DM). Chromium marker allowed higher estimated fecal output (FOe) values when compared to FOR (P < 0.001). Both Ti mean and SD bias (+ 0.074 ± 0.160 kg) were lower than Cr mean and SD bias (+ 0.312 ± 0.272 kg). The Ti fecal output prediction showed lower both RSR (0.586 vs 1.401) and MSPE (0.029 vs 0.167) than Cr prediction. The titanium external marker allowed fecal output estimation with more accuracy in grazing beef cattle trials. A protocol including a once-daily marker dosage associated with a once-daily fecal sampling is plausible, allowing good fecal recovery rates and accurate fecal output estimation.


Assuntos
Digestão , Titânio , Ração Animal/análise , Animais , Bovinos , Compostos de Cromo , Dieta
7.
Rev Esp Quimioter ; 34(6): 525-555, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34348449

RESUMO

The role of certain viruses in the etiology of some tumors is today indisputable, but there is a lack, however, of annoverview of the relationship between viruses and cancer with amultidisciplinary approach. For this reason, the Health Sciences Foundation has convened a group of professionals from different areas of knowledge to discuss the relationship between viruses and cancer, and the present document is the result of these deliberations. Although viruses cause only 10-15% of cancers, advances in oncology research are largely due to the work done during the last century on tumor viruses. The clearest cancer-inducing viruses are: HPV, HBV, HCV, EBV and, depending on the geographical area, HHV-8, HTLV-1 and HIV. HPVs, for example, are considered to be the causative agents of cervical carcinomas and, more recently, of a proportion of other cancers. Among the Herpes viruses, the association with the development of neoplasms is well established for EBV and HHV-8. Viruses can also be therapeutic agents in certain neoplasms and, thus, some oncolytic viruses with selective tropism for tumor cells have been approved for clinical use in humans. It is estimated that the prophylaxis or treatment of viral infections could prevent at least 1.5 million cancer deaths per year.


Assuntos
Neoplasias , Viroses , Humanos , Vírus Oncogênicos , Papillomaviridae , Viroses/epidemiologia
8.
Clín. investig. ginecol. obstet. (Ed. impr.) ; 48(2): 168-171, Abr-Jun 2021. ilus
Artigo em Espanhol | IBECS | ID: ibc-219496

RESUMO

Los tumores de ovario borderline se caracterizan por exhibir un comportamiento intermedio entre los tumores benignos y los carcinomas invasivos. Generalmente se diagnostican en mujeres en edad reproductiva y estadios iniciales, presentando un pronóstico favorable. En estos casos el tratamiento quirúrgico conservador es el gold standard. Sin embargo, en estadios avanzados sigue existiendo controversia entre realizar una estadificación completa o una cirugía conservadora. Presentamos el caso de un tumor borderline seroso de alto grado en una paciente joven, en el que se realizó un tratamiento quirúrgico radical, incluyendo una revisión de la literatura respecto a las opciones terapéuticas de esta enfermedad.(AU)


Ovarian borderline tumours are characterized by exhibiting an intermediate behaviour between benign tumours and invasive carcinomas. They are generally diagnosed in women of reproductive age and early stages, presenting a favourable prognosis. In these cases, conservative surgical treatment is the gold standard. However, in advanced stages there is still controversy between performing complete staging and conservative surgery. We present the case of a high-grade serous borderline tumour in a young patient in which radical surgical treatment was performed, including a review of the literature regarding the therapeutic options for this pathology.(AU)


Assuntos
Humanos , Feminino , Adulto , Neoplasias Ovarianas/cirurgia , Ginecologia , Ovário
9.
J Chem Phys ; 154(4): 041104, 2021 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-33514082

RESUMO

The fundamental vibrational frequency of the B-N stretch in BH3NH3 has eluded gas-phase experimental observation for decades. This work offers a theoretical anharmonic prediction of this mode to be 644 cm-1, using a Cartesian quartic force field at the CCSD(T)-F12/cc-pVTZ-F12 level of theory. The other fundamental frequencies reported herein have a mean absolute error of only 5 cm-1 from the seven available gas-phase experimental frequencies, making the anharmonic vibrational frequencies and rotational constants the most accurate computational data available for BH3NH3 to date. The inclusion of Fermi, Coriolis, and Darling-Dennison resonances is a major source of this accuracy, with the non-resonance-corrected frequencies having a mean absolute error of 10 cm-1. In particular, the inclusion of the 2ν6 = ν5 type 1 Fermi resonance increases the B-N stretching frequency by 14 cm-1 compared to previous work. Ammonia borane also represents one of the largest molecules ever studied by quartic force fields, making this work an important step in extending the breadth of application for these theoretical rovibrational techniques.

10.
Rev. ANACEM (Impresa) ; 15(1): 56-61, 2021. tab, graf
Artigo em Espanhol | LILACS | ID: biblio-1281221

RESUMO

INTRODUCCIÓN: La producción científica ocupa un lugar importante en la formación de estudiantes de medicina. Siendo el objetivo de la Revista ANACEM la promoción temprana de la formación científica de los futuros profesionales médicos, es importante conocer quiénes publican en la revista y sus afiliaciones universitarias. OBJETIVO: Caracterizar a los autores de la revista ANACEM entre los años 2007 y 2018. Material y método: Estudio retrospectivo. La población estudiada fueron todos los autores con publicaciones en la revista ANACEM, excluyendo publicaciones dentro del mismo Volumen. Datos obtenidos directamente de los números publicados por ANACEM digitalmente. Se utilizó el programa Microsoft Excel® para el análisis estadístico. Resultados: Los Volúmenes 5, 6 y 7 fueron los que tuvieron más autores de pregrado. En la totalidad de los Volúmenes la mayoría de los autores fueron hombres, tanto estudiantes como docentes. Un 52,1% de los autores de pregrado fueron internos; mientras que la mayoría de los docentes, 43,7%, fueron médicos especialistas. La Universidad de Concepción fue la universidad con mayor cantidad de autores de pregrado y de docentes. Un 51,8% de los docentes informó afiliación a un hospital. La nacionalidad más común fue la chilena, con un 90,1% de la totalidad de los autores. Discusión: Se vio un aumento en la cantidad de autores de pregrado hasta el Volumen N°7, con un descenso posterior. Se atribuyó el cambio en la cantidad de autores a problemas en la gestión y divulgación de la revista. Las afiliaciones universitarias no fueron informadas siempre por los docentes. Las otras categorías siguen patrones esperados.


INTRODUCTION: Scientific production has an important place in the training of medical students, but there is no clear pictureof the authors in the ANACEM journal. For this reason, it is important to know who publishes in the magazine and their affiliations. OBJECTIVE: To characterize the authors of the ANACEM journal between 2007 and 2018. Material and method: Retrospective study. The population studied were all authors with publications in the ANACEM journal, excluding repeating publications within the same volume. The data was obtained directly from the numbers published by ANACEM digitally. The software used for statistical analysis was Microsoft Excel®. Results: Volumes 5, 6 and 7 had the most undergraduate authors. When analyzing all volumes, the majority of both student authors and professional authors were men. 52.1% of undergraduate authors were interns; while 43.7% of tutors were medical specialists. The university with the largest number of authors was Universidad de Concepción. 51.8% of professional authors reported affiliation to a hospital. The most common nationality was Chilean, with 90.1% of all authors. Discussion: There was an increase in the number of undergraduate authors up to volume n°7, with a subsequent decrease. Changes in the number of authors were attributed to problems in management and divulgation of the journal. Affiliation to universities was not always informed by professionals. The other categories follow expected patterns.


Assuntos
Humanos , Publicações Periódicas como Assunto/estatística & dados numéricos , Autoria , Estudantes de Medicina/estatística & dados numéricos , Universidades/estatística & dados numéricos , Estudos Retrospectivos , Pesquisa Biomédica
11.
Phys Rev Lett ; 123(2): 022502, 2019 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-31386517

RESUMO

A new summation method model of the reactor antineutrino energy spectrum is presented. It is updated with the most recent evaluated decay databases and with our total absorption gamma-ray spectroscopy measurements performed during the last decade. For the first time, the spectral measurements from the Daya Bay experiment are compared with the antineutrino energy spectrum computed with the updated summation method without any renormalization. The results exhibit a better agreement than is obtained with the Huber-Mueller model in the 2-5 MeV range, the region that dominates the detected flux. A systematic trend is found in which the antineutrino flux computed with the summation model decreases with the inclusion of more pandemonium-free data. The calculated flux obtained now lies only 1.9% above that detected in the Daya Bay experiment, a value that may be reduced with forthcoming new pandemonium-free data, leaving less room for a reactor anomaly. Eventually, the new predictions of individual antineutrino spectra for the ^{235}U, ^{239}Pu, ^{241}Pu, and ^{238}U are used to compute the dependence of the reactor antineutrino spectral shape on the fission fractions.

12.
Phys Rev Lett ; 122(4): 042502, 2019 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-30768318

RESUMO

Even mass neutron-rich niobium isotopes are among the principal contributors to the reactor antineutrino energy spectrum. They are also among the most challenging to measure due to the refractory nature of niobium, and because they exhibit isomeric states lying very close in energy. The ß-intensity distributions of ^{100gs,100m}Nb and ^{102gs,102m}Nb ß decays have been determined using the total absorption γ-ray spectroscopy technique. The measurements were performed at the upgraded Ion Guide Isotope Separator On-Line facility at the University of Jyväskylä. Here, the double Penning trap system JYFLTRAP was employed to disentangle the ß decay of the isomeric states. The new data obtained in this challenging measurement have a large impact in antineutrino summation calculations. For the first time the discrepancy between the summation model and the reactor antineutrino measurements in the region of the shape distortion has been reduced.

13.
J Food Sci Technol ; 54(13): 4427-4435, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29184249

RESUMO

In this work, a comparative study between spray drying (SD) of fresh egg by either maltodextrin (MD) or nopal-mucilage (MN) as stabilizing vectors was made. The powders obtained were characterized for drying performance, moisture content, chemical proximate analysis, thermal analysis (TGA), chemical composition (FTIR), microscopy (SEM) and rheology (viscoelasticity and steady state simple shear viscosity). Infrared analysis showed that MN has the effect of a thickening agent rather than an encapsulating one. Results indicated that SD egg with MN produced a high thermal and mechanical stable product and rendered the highest drying performance, producing a more uniform and defined sphere-shaped morphology in comparison to egg SD either alone and with MD.

14.
Artigo em Inglês | MEDLINE | ID: mdl-28596904

RESUMO

The purpose of this paper is to describe the development and initial accomplishments of a training program of young leaders in community mental health research as part of a Latin American initiative known as RedeAmericas. RedeAmericas was one of five regional 'Hubs' funded by the National Institute of Mental Health (NIMH) to improve community mental health care and build mental health research capacity in low- and middle-income countries. It included investigators in six Latin American cities - Santiago, Chile; Medellín, Colombia; Rio de Janeiro, Brazil; and Córdoba, Neuquén, and Buenos Aires in Argentina - working together with a team affiliated with the Global Mental Health program at Columbia University in New York City. One component of RedeAmericas was a capacity-building effort that included an Awardee program for early career researchers in the mental health field. We review the aims of this component, how it developed, and what was learned that would be useful for future capacity-building efforts, and also comment on future prospects for maintaining this type of effort.

15.
Phys Rev Lett ; 115(10): 102503, 2015 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-26382674

RESUMO

The antineutrino spectra measured in recent experiments at reactors are inconsistent with calculations based on the conversion of integral beta spectra recorded at the ILL reactor. (92)Rb makes the dominant contribution to the reactor antineutrino spectrum in the 5-8 MeV range but its decay properties are in question. We have studied (92)Rb decay with total absorption spectroscopy. Previously unobserved beta feeding was seen in the 4.5-5.5 region and the GS to GS feeding was found to be 87.5(25)%. The impact on the reactor antineutrino spectra calculated with the summation method is shown and discussed.

16.
Phys Rev Lett ; 115(6): 062502, 2015 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-26296113

RESUMO

Total absorption spectroscopy is used to investigate the ß-decay intensity to states above the neutron separation energy followed by γ-ray emission in (87,88)Br and (94)Rb. Accurate results are obtained thanks to a careful control of systematic errors. An unexpectedly large γ intensity is observed in all three cases extending well beyond the excitation energy region where neutron penetration is hindered by low neutron energy. The γ branching as a function of excitation energy is compared to Hauser-Feshbach model calculations. For (87)Br and (88)Br the γ branching reaches 57% and 20%, respectively, and could be explained as a nuclear structure effect. Some of the states populated in the daughter can only decay through the emission of a large orbital angular momentum neutron with a strongly reduced barrier penetrability. In the case of neutron-rich (94)Rb the observed 4.5% branching is much larger than the calculations performed with standard nuclear statistical model parameters, even after proper correction for fluctuation effects on individual transition widths. The difference can be reconciled by introducing an enhancement of 1 order of magnitude in the photon strength to neutron strength ratio. An increase in the photon strength function of such magnitude for very neutron-rich nuclei, if it proves to be correct, leads to a similar increase in the (n,γ) cross section that would have an impact on r process abundance calculations.

17.
Philos Trans A Math Phys Eng Sci ; 372(2029)2014 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-25332388

RESUMO

Liquid crystal flexoelectric actuation uses an imposed electric field to create membrane bending, and it is used by the outer hair cells (OHCs) located in the inner ear, whose role is to amplify sound through generation of mechanical power. Oscillations in the OHC membranes create periodic viscoelastic flows in the contacting fluid media. A key objective of this work on flexoelectric actuation relevant to OHCs is to find the relations and impact of the electromechanical properties of the membrane, the rheological properties of the viscoelastic media, and the frequency response of the generated mechanical power output. The model developed and used in this work is based on the integration of: (i) the flexoelectric membrane shape equation applied to a circular membrane attached to the inner surface of a circular capillary and (ii) the coupled capillary flow of contacting viscoelastic phases, such that the membrane flexoelectric oscillations drive periodic viscoelastic capillary flows, as in OHCs. By applying the Fourier transform formalism to the governing equation, analytical expressions for the transfer function associated with the curvature and electrical field and for the power dissipation of elastic storage energy were found.

18.
J Antimicrob Chemother ; 69(9): 2536-40, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24833755

RESUMO

OBJECTIVES: To present clinical experience with a regimen including abacavir/lamivudine + darunavir/ritonavir in a cohort of HIV-1-infected patients. METHODS: A retrospective, multicentre cohort study, including all consecutive adult HIV-1-infected patients who started abacavir/lamivudine + darunavir/ritonavir from April 2008 to December 2010 and had at least one follow-up visit. The primary endpoint was HIV-1 viral load (VL) <40 copies/mL at week 48. RESULTS: One hundred and eighty-three patients (42 naive and 141 experienced) from 19 hospitals in Spain were studied. The median follow-up was 26.7 (0.5-58.6) months, 79.8% were men, the median age was 47.1 (21.4-80.5) years, 26.2% had AIDS and 38.8% were positive for hepatitis C virus. At baseline, the median CD4 count was 246 cells/mm(3) in naive patients and 393 cells/mm(3) in experienced patients and the median VL was 4.80 and <1.59 log copies/mL, respectively. At week 48, 81.8% of naive patients and 84.2% of experienced patients receiving the regimen reached a VL <40 copies/mL, whereas at 96 weeks this occurred in 90.5% and 92.8%, respectively. CD4 cell count increases at 48 and 96 weeks were +176.5 and +283.5 cells/mm(3) in naive patients and +74.9 and +93 cells/mm(3) in experienced patients, respectively. Overall, 86 (47%) patients discontinued the study regimen, in many cases possibly related to non-medical reasons, such as drug switches to reduce cost or changes in address due to economic constraints. Three patients died of causes unrelated to therapy and 19 (10.4%) discontinued the regimen due to adverse events. CONCLUSIONS: In our cohort, abacavir/lamivudine + darunavir/ritonavir was safe, well tolerated and achieved high rates of virological suppression. In a proportion of patients, discontinuation of this effective regimen was possibly due to non-medical reasons.


Assuntos
Fármacos Anti-HIV/uso terapêutico , Terapia Antirretroviral de Alta Atividade/métodos , Didesoxinucleosídeos/uso terapêutico , Infecções por HIV/tratamento farmacológico , Lamivudina/uso terapêutico , Ritonavir/uso terapêutico , Sulfonamidas/uso terapêutico , Adulto , Idoso , Idoso de 80 Anos ou mais , Fármacos Anti-HIV/efeitos adversos , Terapia Antirretroviral de Alta Atividade/efeitos adversos , Estudos de Coortes , Darunavir , Didesoxinucleosídeos/efeitos adversos , Combinação de Medicamentos , Feminino , HIV-1/isolamento & purificação , Humanos , Lamivudina/efeitos adversos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Ritonavir/efeitos adversos , Espanha , Sulfonamidas/efeitos adversos , Resultado do Tratamento , Carga Viral , Adulto Jovem
19.
HIV Clin Trials ; 15(2): 57-61, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24710919

RESUMO

BACKGROUND: Drug intolerance is one of the main reasons for switching antiretroviral therapy in HIV-infected patients. Etravirine (ETR) has demonstrated good tolerability in clinical trials and may be an option for patients who switch therapy due to adverse events. METHODS: We retrospectively reviewed all patients who had switched to an ETR-containing regimen in our center due to side effects. Virological suppression, ETR discontinuation, and reasons for discontinuation were studied. RESULTS: A total of 78 patients started treatment with ETR in our center due to previous regimen toxicity. Most of them were men (83.3%), and the median time of infection was 14 years (IQR, 6.5-20 years). HIV RNA was <35 copies/mL in 88.3% of patients, although 33% had archived non-nucleos(t)ide reverse transcriptase inhibitor (NNRTI) mutations that did not compromise ETR efficacy. Efavirenz was the drug most often replaced (38.5%), followed by atazanavir (20.5%) and lopinavir (6.4%). The fixed combination of Trizivir was changed in another 10.3% of patients. After a median follow-up of 14 months (IQR, 6-23), the rate of virologic suppression was 79.5% and 98.4% in intention-to-treat and on-treatment analysis, respectively. Seven patients discontinued treatment due to adverse events (3 gastrointestinal disturbances, 2 rashes, 1 swelling, and 1 neuropathy). ETR was combined with 2 nucleos(t)ide analogues in 75.4% of patients. CONCLUSION: In HIV patients who report drug side effects, switching to an ETR-containing regimen is a safe strategy in terms of virological suppression and toxicity.


Assuntos
Fármacos Anti-HIV/administração & dosagem , Infecções por HIV/tratamento farmacológico , HIV-1/efeitos dos fármacos , Piridazinas/administração & dosagem , Adulto , Fármacos Anti-HIV/efeitos adversos , Feminino , Seguimentos , Infecções por HIV/complicações , Hepatite B Crônica/complicações , Hepatite C Crônica/complicações , Humanos , Masculino , Pessoa de Meia-Idade , Nitrilas , Piridazinas/efeitos adversos , Pirimidinas , Estudos Retrospectivos , Espanha , Resultado do Tratamento
20.
Soft Matter ; 10(10): 1611-20, 2014 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-24651833

RESUMO

Phase ordering over solid substrates is a ubiquitous and important soft material transformation process whose description incorporates wetting, anchoring and phase transition kinetics. In this paper the kinetics of the isotropic-to-nematic isothermal phase transition over a flat solid surface in a growing spherical drop is analyzed based on the Landau-de Gennes Q-tensor order parameter equations. The model, based on a previously derived interface force balance and a newly derived contact line force balance, is shown to be consistent with the generic model of conservative interface and contact line motions. The advancing dynamic contact angle equation is extracted from kinematic compatibility between the moving isotropic-nematic interface and contact line. A tractable surface phase transition kinetic model obtained by focusing on the dominant phase transition and wetting driving forces yields: (i) the constant advancing dynamic contact angle θ, and (ii) the contact line speed as a function of undercooling ΔT. It is shown that as undercooling increases, the surface phase transition mode approaches the bulk phase transition mode, such that θ approaches π. The elastic and wetting parameters that control the phase transformation process are identified and experiments for their determination are defined. These dynamic wetting and surface phase transition results significantly expand existing characterization methods of LC-substrate interfaces based on static phase transition droplet methods.


Assuntos
Modelos Teóricos , Transição de Fase , Molhabilidade , Cinética , Propriedades de Superfície , Temperatura , Termodinâmica
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