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1.
Nature ; 628(8009): 741-745, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38658686

RESUMEN

Extensive efforts have been undertaken to combine superconductivity and the quantum Hall effect so that Cooper-pair transport between superconducting electrodes in Josephson junctions is mediated by one-dimensional edge states1-6. This interest has been motivated by prospects of finding new physics, including topologically protected quasiparticles7-9, but also extends into metrology and device applications10-13. So far it has proven challenging to achieve detectable supercurrents through quantum Hall conductors2,3,6. Here we show that domain walls in minimally twisted bilayer graphene14-18 support exceptionally robust proximity superconductivity in the quantum Hall regime, allowing Josephson junctions to operate in fields close to the upper critical field of superconducting electrodes. The critical current is found to be non-oscillatory and practically unchanging over the entire range of quantizing fields, with its value being limited by the quantum conductance of ballistic, strictly one-dimensional, electronic channels residing within the domain walls. The system described is unique in its ability to support Andreev bound states at quantizing fields and offers many interesting directions for further exploration.

2.
J Assist Reprod Genet ; 38(8): 2193-2198, 2021 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-33754252

RESUMEN

PURPOSE: This study aims to know what proportion of culture day 5 pre-blastocyst-stage embryos develop into blastocysts by culture day 6 and what patient and cycle characteristics are associated with delayed blastocyst formation. METHODS: A retrospective observational cohort analysis was performed including a total of 9886 embryos from 1008 IVF cycles in 835 patients, who underwent treatment between January 1, 2016, and December 31, 2018. Autologous fresh in vitro fertilization (IVF) cycles at a single academic center were included in the analysis. Embryos were group-cultured using single-step culture media. Blastulation was defined as the presence of a new blastocyst. Usable blastulation was defined as the presence of a new good or excellent quality, expanded, hatching, or hatched blastocysts. RESULTS: The mean blastulation rate between days 5 and 6 of extended embryo culture was 30.9%. The mean percentage of embryos developing into usable blastocyst-stage embryos was 19.8%. The factors associated with blastulation on day 6 included the total number of embryos and the number of pre-blastocysts on day 5, as well as the use of ICSI. Age, the number of total embryos, those remained in culture and pre-blastocysts, as well as the blastulation rate on day 5 were associated with usable blastulation. CONCLUSION: It is important to know the usable blastocyst development rate between culture days 5 and 6 in order to adequately counsel patients debating whether to proceed with fresh ET on day 5 or forego ET with the expectation that embryos will be biopsied for PGT and/or cryopreserved on culture day 6. Our findings provide evidence to help guide patients in this difficult decision.


Asunto(s)
Blastocisto/citología , Técnicas de Cultivo de Embriones/métodos , Implantación del Embrión , Transferencia de Embrión , Embrión de Mamíferos/citología , Fertilización In Vitro/métodos , Adulto , Criopreservación , Femenino , Humanos , Embarazo , Índice de Embarazo , Estudios Retrospectivos
3.
Osteoporos Int ; 29(8): 1827-1832, 2018 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-29744567

RESUMEN

We evaluated osteoporosis treatment and DEXA utilization rates of patients who were admitted for hip fracture in a single healthcare system in Hawaii from 2015 to 2016. We found that osteoporosis treatment and DEXA utilization rates were low, highlighting a critical gap in osteoporosis care after admission for hip fracture. INTRODUCTION: The objective of this study was to evaluate osteoporosis care after an admission for hip fracture at three community hospitals within a single healthcare system in Hawaii. METHODS: A retrospective chart review was conducted (n = 428) of patients ≥ 50 years and hospitalized for hip fractures between January 1, 2015, and May 31, 2016, at three major hospitals within Hawaii Pacific Health, a large healthcare system in Hawaii. Basic demographics were collected, and medications prescribed were quantified and described within 1 year of hip fracture. Logistic regression was used to evaluate the association between collected variables and the odds of osteoporosis treatment. RESULTS: Only 115 (26.9%) patients were prescribed a medication for osteoporosis as a secondary prevention within a year of hospitalization for hip fracture. DEXA scans were performed in 137 (32.0%) patients. Most of the treated patients were prescribed oral bisphosphonates. Treatment facility, female gender, and higher BMI were found to be predictive factors for osteoporosis treatment. CONCLUSION: The use of osteoporosis medication for secondary prevention after admission for hip fracture in Hawaii is low. Efforts need to be made to improve treatment rates, especially among males.


Asunto(s)
Conservadores de la Densidad Ósea/uso terapéutico , Fracturas de Cadera/prevención & control , Osteoporosis/tratamiento farmacológico , Fracturas Osteoporóticas/prevención & control , Absorciometría de Fotón/estadística & datos numéricos , Anciano , Anciano de 80 o más Años , Índice de Masa Corporal , Utilización de Medicamentos/estadística & datos numéricos , Utilización de Equipos y Suministros/estadística & datos numéricos , Femenino , Hawaii , Fracturas de Cadera/etiología , Hospitalización/estadística & datos numéricos , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Prevención Secundaria/normas , Prevención Secundaria/estadística & datos numéricos , Factores Sexuales
4.
Microb Ecol ; 75(4): 930-940, 2018 May.
Artículo en Inglés | MEDLINE | ID: mdl-29116347

RESUMEN

Methanogenesis and sulfate reduction are important microbial processes in hypersaline environments. However, key aspects determining substrate competition between these microbial processes have not been well documented. We evaluated competitive and non-competitive substrates for stimulation of both processes through microcosm experiments of hypersaline microbial mat samples from Guerrero Negro, Baja California Sur, Mexico, and we assessed the effect of these substrates on the microbial community composition. Methylotrophic methanogenesis evidenced by sequences belonging to methanogens of the family Methanosarcinaceae was found as the dominant methanogenic pathway in the studied hypersaline microbial mat. Nevertheless, our results showed that incubations supplemented with acetate and lactate, performed in absence of sulfate, also produced methane after 40 days of incubation, apparently driven by hydrogenotrophic methanogens affiliated to the family Methanomicrobiaceae. Sulfate reduction was mainly stimulated by addition of acetate and lactate; however, after 40 days of incubation, an increase of the H2S concentrations in microcosms amended with trimethylamine and methanol was also observed, suggesting that these substrates are putatively used for sulfate reduction. Moreover, 16S rRNA gene sequencing analysis showed remarkable differences in the microbial community composition among experimental treatments. In the analyzed sample amended with acetate, sulfate-reducing bacteria (SRB) belonging to the family Desulfobacteraceae were dominant, while members of Desulfohalobiaceae, Desulfomicrobiaceae, and Desulfovibrionaceae were found in the incubation with lactate. Additionally, we detected an unexpected high abundance of unclassified Hydrogenedentes (near 25%) in almost all the experimental treatments. This study contributes to better understand methanogenic and sulfate-reducing activities, which play an important role in the functioning of hypersaline environments.


Asunto(s)
Bacterias/metabolismo , Crecimiento Quimioautotrófico , Metano/metabolismo , Microbiota/fisiología , Salinidad , Sulfatos/metabolismo , Bacterias/clasificación , Bacterias/genética , Biodiversidad , Sulfuro de Hidrógeno/metabolismo , Metilaminas/metabolismo , México , Microbiota/genética , Filogenia , ARN Ribosómico 16S/genética
5.
Biodegradation ; 29(5): 429-442, 2018 10.
Artículo en Inglés | MEDLINE | ID: mdl-29948518

RESUMEN

Availability of fixed nitrogen is a pivotal driver on primary productivity in the oceans, thus the identification of key processes triggering nitrogen losses from these ecosystems is of major importance as they affect ecosystems function and consequently global biogeochemical cycles. Denitrification and anaerobic ammonium oxidation coupled to nitrite reduction (Anammox) are the only identified marine sinks for fixed nitrogen. The present study provides evidence indicating that anaerobic ammonium oxidation coupled to the reduction of sulfate, the most abundant electron acceptor present in the oceans, prevails in marine sediments. Tracer analysis with 15N-ammonium revealed that this microbial process, here introduced as Sulfammox, accounts for up to 5 µg 15N2 produced g-1 day-1 in sediments collected from the eastern tropical North Pacific coast. Raman and X-ray diffraction spectroscopies revealed that elemental sulfur and sphalerite (ZnFeS) were produced, besides free sulfide, during the course of Sulfammox. Anaerobic ammonium oxidation linked to Fe(III) reduction (Feammox) was also observed in the same marine sediments accounting for up to 2 µg 15N2 produced g-1 day-1. Taxonomic characterization, based on 16S rRNA gene sequencing, of marine sediments performing the Sulfammox and Feammox processes revealed the microbial members potentially involved. These novel nitrogen sinks may significantly fuel nitrogen loss in marine environments. These findings suggest that the interconnections among the oceanic biogeochemical cycles of N, S and Fe are much more complex than previously considered.


Asunto(s)
Compuestos de Amonio/metabolismo , Compuestos Férricos/metabolismo , Sedimentos Geológicos/química , Nitrógeno/análisis , Agua de Mar/microbiología , Sulfatos/metabolismo , Anaerobiosis , Bacterias/metabolismo , Biodegradación Ambiental , Electrones , Hierro/análisis , Oxidación-Reducción , Azufre/metabolismo
6.
Appl Environ Microbiol ; 83(11)2017 06 01.
Artículo en Inglés | MEDLINE | ID: mdl-28341676

RESUMEN

Wetlands constitute the main natural source of methane on Earth due to their high content of natural organic matter (NOM), but key drivers, such as electron acceptors, supporting methanotrophic activities in these habitats are poorly understood. We performed anoxic incubations using freshly collected sediment, along with water samples harvested from a tropical wetland, amended with 13C-methane (0.67 atm) to test the capacity of its microbial community to perform anaerobic oxidation of methane (AOM) linked to the reduction of the humic fraction of its NOM. Collected evidence demonstrates that electron-accepting functional groups (e.g., quinones) present in NOM fueled AOM by serving as a terminal electron acceptor. Indeed, while sulfate reduction was the predominant process, accounting for up to 42.5% of the AOM activities, the microbial reduction of NOM concomitantly occurred. Furthermore, enrichment of wetland sediment with external NOM provided a complementary electron-accepting capacity, of which reduction accounted for ∼100 nmol 13CH4 oxidized · cm-3 · day-1 Spectroscopic evidence showed that quinone moieties were heterogeneously distributed in the wetland sediment, and their reduction occurred during the course of AOM. Moreover, an enrichment derived from wetland sediments performing AOM linked to NOM reduction stoichiometrically oxidized methane coupled to the reduction of the humic analogue anthraquinone-2,6-disulfonate. Microbial populations potentially involved in AOM coupled to microbial reduction of NOM were dominated by divergent biota from putative AOM-associated archaea. We estimate that this microbial process potentially contributes to the suppression of up to 114 teragrams (Tg) of CH4 · year-1 in coastal wetlands and more than 1,300 Tg · year-1, considering the global wetland area.IMPORTANCE The identification of key processes governing methane emissions from natural systems is of major importance considering the global warming effects triggered by this greenhouse gas. Anaerobic oxidation of methane (AOM) coupled to the microbial reduction of distinct electron acceptors plays a pivotal role in mitigating methane emissions from ecosystems. Given their high organic content, wetlands constitute the largest natural source of atmospheric methane. Nevertheless, processes controlling methane emissions in these environments are poorly understood. Here, we provide tracer analysis with 13CH4 and spectroscopic evidence revealing that AOM linked to the microbial reduction of redox functional groups in natural organic matter (NOM) prevails in a tropical wetland. We suggest that microbial reduction of NOM may largely contribute to the suppression of methane emissions from tropical wetlands. This is a novel avenue within the carbon cycle in which slowly decaying NOM (e.g., humic fraction) in organotrophic environments fuels AOM by serving as a terminal electron acceptor.


Asunto(s)
Bacterias/metabolismo , Metano/metabolismo , Anaerobiosis , Antraquinonas/metabolismo , Bacterias/clasificación , Bacterias/genética , Bacterias/aislamiento & purificación , Oxidación-Reducción , Humedales
7.
Antonie Van Leeuwenhoek ; 110(11): 1453-1465, 2017 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-28608318

RESUMEN

Considering the great agronomic and environmental importance of denitrification, the aim of the present study was to study the temporal and spatial factors controlling the abundance and activity of denitrifying bacterial communities in a range of eight agricultural soils over 2 years. Abundance was quantified by qPCR of the nirS, nirK and nosZ genes, and the potential denitrification enzyme activity (DEA) was estimated. Our data showed a significant temporal variation considerably high for the abundance of nirK-harboring communities, followed by nosZ and nirS communities. Regarding soil parameters, the abundances of nosZ, nirS and nirK were mostly influenced by organic material, pH, and slightly by NO3-, respectively. Soil texture was the most important factor regulating DEA, which could not be explained by the abundance of denitrifiers. Analyses of general patterns across lands to understand the soil functioning is not an easy task because the multiple factors influencing processes such as denitrification can skew the data. Careful analysis of atypical sites are necessary to classify the soils according to trait similarity and in this way reach a better predictability of the denitrifiers dynamics.


Asunto(s)
Bacterias/enzimología , Desnitrificación/fisiología , Nitrito Reductasas/metabolismo , Microbiología del Suelo , Suelo/química , Agricultura , Genes Bacterianos/genética , Países Bajos , Nitrito Reductasas/genética , Reacción en Cadena en Tiempo Real de la Polimerasa , Análisis de Regresión , Análisis Espacio-Temporal
8.
J Clin Pharm Ther ; 42(4): 404-413, 2017 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-28485006

RESUMEN

WHAT IS KNOWN AND OBJECTIVE: Proactive synchronization of medication refills through an appointment-based model (ABM) is a community pharmacy-based intervention targeting adherence to medications. We aimed to systematically review evidence on the impact of the ABM on medication taking behaviour, health resource utilization, clinical outcomes and the preferences of patients and providers. METHODS: We conducted a systematic literature search of MEDLINE and Scopus from database inception through 6 February 2017. Studies were included if they were original investigations evaluating the impact of the ABM on at least one outcome of interest and published in the peer-reviewed literature as a full-text manuscript in the English language. Outcomes included medication taking behaviour, clinical and economic outcomes, health resource utilization, and patient or provider satisfaction. Data were synthesized qualitatively. RESULTS: Five studies, mostly observational in design and with low risk of bias, were included. Objective measures of medication taking behaviour were consistently improved in patients enrolled in an ABM vs control, indicating an association between appointment-based medication synchronization with improved adherence and decreased likelihood of non-persistence. A single decision analysis indicates a cost savings over 1 year associated with the appointment-based medication synchronization programme modelled, for hypertension, diabetes and hyperlipidaemia. Limited data regarding health resource utilization and clinical outcomes and patient or provider satisfaction exist and are currently inconclusive. WHAT IS NEW AND CONCLUSION: The ABM provides a unique, patient-centred service to improve medication adherence amongst patients taking chronic medications while demonstrating a positive financial return on investment. Future research is needed to determine the impact of the ABM on final health outcomes.


Asunto(s)
Citas y Horarios , Servicios Comunitarios de Farmacia/organización & administración , Cumplimiento de la Medicación , Diabetes Mellitus/tratamiento farmacológico , Humanos , Hiperlipidemias/tratamiento farmacológico , Hipertensión/tratamiento farmacológico , Preparaciones Farmacéuticas/administración & dosificación
9.
Org Biomol Chem ; 14(16): 3975-80, 2016 Apr 28.
Artículo en Inglés | MEDLINE | ID: mdl-27049933

RESUMEN

Sulfur-lone pair interactions are important conformational control elements in sulfur-containing heterocycles that abound in pharmaceuticals, natural products, agrochemicals, polymers and other important classes of organic molecules. Nonetheless, the role of intramolecular sulfur-lone pair interactions in the binding of small molecules to receptors is often overlooked. Here we analyze the magnitudes and origins of these interactions for a variety of biologically relevant small molecules using quantum chemical and automated docking calculations. In most cases examined in this study, the lowest energy conformation of the small molecule displays a sulfur-lone pair close contact. However, docking studies, both published and new, often predict that conformations without sulfur-lone pair contacts have the best binding affinity for their respective receptors. This is a serious problem. Since many of these predicted bound conformations are not actually energetically accessible, pursuing design (e.g., drug design) around these binding modes necessarily will lead, serendipity aside, to dead end designs. Our results constitute a caution that one best not neglect these interactions when predicting the binding affinities of potential ligands (drugs or not) for hosts (enzymes, receptors, DNA, RNA, synthetic hosts). Moreover, a better understanding and awareness of sulfur-lone pair interactions should facilitate the rational modulation of host-guest interactions involving sulfur-containing molecules.


Asunto(s)
Diseño de Fármacos , Preparaciones Farmacéuticas/metabolismo , Receptores de Superficie Celular/metabolismo , Cristalografía por Rayos X , Modelos Moleculares , Termodinámica
10.
Nicotine Tob Res ; 18(5): 857-63, 2016 May.
Artículo en Inglés | MEDLINE | ID: mdl-26391580

RESUMEN

INTRODUCTION: Little is known about dissolvable tobacco products (DTPs) compared with other alternative tobacco products (ATPs) like e-cigarettes and snus. We sought to understand US adults' awareness and use of DTPs. METHODS: A nationally representative sample of US adults (age ≥ 18 years, N = 17 522) completed an online survey in March 2013 assessing their awareness and use of DTPs. RESULTS: Approximately 16% of all respondents were aware of DTPs. Few reported ever using DTPs (1.6%). DTP awareness among all respondents was greatest among males, younger adults, current and former smokers, never married respondents, blacks and Latinos, and those who used other ATPs. Among current smokers, DTP awareness was greatest for males, younger adults, blacks and Latinos, those who used other ATPs, and Southerners. DTP use among all respondents was greatest among males, younger adults, Lesbian, Gay, Bisexual, and Transgender (LGBT) respondents, former and current smokers, and those who used other ATPs. Among current smokers, DTP use was greatest among males, younger adults, LGBT respondents, those who used other ATPs, those who intended to quit, and those who received medical advice to quit. CONCLUSIONS: DTP awareness and use have increased since 2009. DTPs are being used as smoking cessation aids thereby increasing risk of polytobacco use. Medical professionals should emphasize use of empirically-supported smoking cessation aids when advising patients to quit. Regulations are needed to prevent tobacco company promotion of DTPs as smoking cessation aids and to inform consumers of the risks associated with DTPs and polytobacco use. Increased national surveillance of DTP use is recommended.


Asunto(s)
Cese del Hábito de Fumar/métodos , Fumar/epidemiología , Encuestas y Cuestionarios/normas , Productos de Tabaco , Tabaquismo/epidemiología , Adulto , Anciano , Estudios Transversales , Femenino , Conocimientos, Actitudes y Práctica en Salud , Humanos , Masculino , Persona de Mediana Edad , Formulación de Políticas , Vigilancia de la Población , Cese del Hábito de Fumar/estadística & datos numéricos , Productos de Tabaco/estadística & datos numéricos , Tabaquismo/psicología , Estados Unidos/epidemiología
11.
J Clin Pharm Ther ; 41(4): 371-82, 2016 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-27245498

RESUMEN

WHAT IS KNOWN AND OBJECTIVE: Optimal utilization of opioid analgesics is significantly limited by the central nervous system adverse effects and misuse/abuse potential of currently available drugs. It has been postulated that opioid-associated adverse effects and abuse potential would be greatly reduced if opioids could be excluded from reaching the brain. We review the basic science and clinical evidence of one such approach - peripherally restricted kappa-opioid receptor (KOR) agonists (pKORAs). METHODS: Published and unpublished literature, websites and other sources were searched for basic science and clinical information related to the potential benefits and development of peripherally restricted kappa-opioid receptor agonists. Each source was summarized, reviewed and assessed. RESULTS: The historical development of pKORAs can be traced from the design of increasingly KOR-selective agonists, elucidation of the pharmacologic attributes of such compounds and strategies to restrict passage across the blood-brain barrier. Novel compounds are under development and have progressed to clinical trials. WHAT IS NEW AND CONCLUSIONS: The results from recent clinical trials suggest that peripherally restricted opioids can be successfully designed and that they can retain analgesic efficacy with a more favourable adverse effect profile.


Asunto(s)
Analgésicos Opioides/uso terapéutico , Dolor/tratamiento farmacológico , Receptores Opioides kappa/agonistas , Analgésicos Opioides/efectos adversos , Analgésicos Opioides/farmacología , Animales , Barrera Hematoencefálica/metabolismo , Diseño de Fármacos , Humanos , Trastornos Relacionados con Opioides/epidemiología , Trastornos Relacionados con Opioides/prevención & control , Distribución Tisular
12.
Cultur Divers Ethnic Minor Psychol ; 22(2): 205-14, 2016 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-25844566

RESUMEN

OBJECTIVE: This study investigated the association between evaluated need and mental health service use among African-American emerging adults, when controlling for other predictor variables. METHOD: Secondary analysis of data from the National Survey of American Life (2001-2003) was conducted. A nationally representative sample of African-American emerging adults, ages 18 to 29 years (N = 806), was assessed with the Composite International Diagnostic Interview. The sample included females and males with a mean age of 23 years. Evaluated need was determined by endorsement of mood, anxiety, substance use, or impulse control diagnoses. Respondents who reported ever voluntarily using mental health or general medical services to address these problems were considered to have used services. RESULTS: Forty-seven percent of the sample demonstrated an evaluated need for services, whereas a quarter of the sample used services in their lifetime. Respondents who were females, had received religious/spiritual support, and who had an evaluated need for services were significantly more likely to have used services in their lifetime compared with males, those who had not received religious/spiritual support, and those without a need for services. CONCLUSIONS: Literature indicates that evaluated need is a strong predictor of mental health service use, yet research examining its impact on service use among African American emerging adults is limited. This study found that along with having an evaluated need, this population was more likely to use services when supported by a religious/spiritual leader. Mental health outreach and education that incorporates the informal support systems identified by African American emerging adults, particularly males, is needed.


Asunto(s)
Ansiedad/diagnóstico , Negro o Afroamericano/psicología , Necesidades y Demandas de Servicios de Salud , Servicios de Salud Mental/provisión & distribución , Trastornos Relacionados con Sustancias/diagnóstico , Adolescente , Adulto , Ansiedad/etnología , Ansiedad/psicología , Femenino , Encuestas de Atención de la Salud , Humanos , Conducta Impulsiva , Masculino , Servicios de Salud Mental/estadística & datos numéricos , Modelos Estadísticos , Espiritualidad , Trastornos Relacionados con Sustancias/etnología , Trastornos Relacionados con Sustancias/psicología , Estados Unidos , Adulto Joven
13.
Clin Exp Allergy ; 42(12): 1734-44, 2012 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-23181789

RESUMEN

BACKGROUND: The mechanisms by which viruses induce asthma exacerbations are not well understood. OBJECTIVE: We characterized fluctuations in nasal aspirate cytokines during naturally occurring respiratory viral infections in children with asthma. METHODS: Sixteen children underwent home collections of nasal aspirates when they were without cold symptoms and again during self-reported respiratory illnesses. The presence of viral infection was ascertained by multiplex PCR. Cytokines were measured using multiplex immune assay. mRNA expression for selected markers of viral infection was measured using RT-PCR. A cumulative respiratory symptom score was calculated for each day of measurement. Generalized estimated equations were used to evaluate associations between viral infection and marker elevation, and between marker elevation and symptom score. RESULTS: The 16 patients completed a total of 37 weeks of assessment (15 'well' weeks; 22 self-assessed 'sick' weeks). Viral infections were detected in 3 of the 'well' weeks and 17 of the 'sick' weeks (10 rhinovirus, three coronavirus, two influenza A, two influenza B, two respiratory syncytial virus, one parainfluenza). Compared to virus-negative well weeks, nasal aspirate IFN-γ, CXCL8/IL-8, CXCL10/IP-10, CCL5/RANTES, CCL11/eotaxin-1, CCL2/MCP-1, CCL4/MIP-1ß, CCL7/MCP-3, and CCL20/MIP3α protein levels increased during virus-positive sick weeks. Only a subset of cytokines (IFN-γ, CXCL8, CCL2, CCL4, CCL5, and CCL20) correlated with self-reported respiratory tract symptoms. While many aspirates were dilute and showed no mRNA signal, viral infection significantly increased the number of samples that were positive for IFN-λ1, IFN-λ2/3, TLR3, RIG-I, and IRF7 mRNA. CONCLUSIONS AND CLINICAL RELEVANCE: We conclude that in children with asthma, naturally occurring viral infections apparently induce a robust innate immune response including expression of specific chemokines, IFNs, and IFN-responsive genes.


Asunto(s)
Asma , Citocinas/metabolismo , Cavidad Nasal/inmunología , Infecciones del Sistema Respiratorio/inmunología , Virosis/inmunología , Virus/inmunología , Adolescente , Asma/inmunología , Asma/virología , Quimiocinas/inmunología , Quimiocinas/metabolismo , Niño , Citocinas/genética , Citocinas/inmunología , Femenino , Humanos , Inmunidad Innata , Interferones/inmunología , Interferones/metabolismo , Masculino , Infecciones del Sistema Respiratorio/diagnóstico , Infecciones del Sistema Respiratorio/fisiopatología , Infecciones del Sistema Respiratorio/virología , Virosis/diagnóstico , Virosis/fisiopatología , Virosis/virología , Virus/clasificación , Virus/genética , Virus/aislamiento & purificación
14.
Pathol Biol (Paris) ; 59(2): 113-21, 2011 Apr.
Artículo en Francés | MEDLINE | ID: mdl-20828940

RESUMEN

UNLABELLED: The PCR assays are currently used in diagnosis of enterovirus (EV) meningitis. Nevertheless, the use of molecular diagnosis of EV should be investigated in respiratory tract infections (RTI). OBJECTIVES: To perform enterovirus molecular diagnostic tools, PCR and genotyping, in nasal samples for diagnostic and epidemiologic purposes. METHODS: During 2008, 3612 nasal specimen (NS) were studied by IFD and MRC5 culture. Next, we realised successively viral isolation on HuH7 culture (for NS negative by IFD assay) and a duplex PCR enterovirus-rhinovirus for the 816 HuH7 positive supernatants. Furthermore, 327 NS collected from neonates were systematically tested by a real-time RT-PCR. This assay was used in routine for EV diagnosis setting in cerebrospinal fluid. Enterovirus genotyping was then performed for the 68 positive supernatants. RESULTS: Thirty-five NS (0.97%) were positive for EV by culture (MRC5). A combination of both PCR assays, PEVRV and PEV, allowed an additional identification of 41 EV, eight EV-RV and 12 RV, increasing the number of positive to 96 NS (2.6%). Among the neonates, 32 NS (11.3%) were positive for EV by PEV. Of the 98 NS tested by the two PCR assays (PEV and PEVRV), 27 were positive and we detected 10 EV, five EV-RV and 12 RV. From January to December 2008, the circulation of EV showed the usual peak in June-July when a small outbreak of aseptic meningitis occurred and an additional autumnal peak corresponding to respiratory tract infections. Five main serotypes were isolated: 19 EV68 (29.7%), 12 CB3 (18.7%), nine E3 (14,1%), six CA9 (9.4%) and six CB1 (9.4%); the 19 EV68 were isolated in October-November and 17/19 (89.5%) of positive patients were hospitalised for severe respiratory diseases. CONCLUSION: The use of molecular screening techniques (PCR assays and genotyping) on nasal samples collected from patients with respiratory infections allowed a prospective, effective and precise identification of circulating strains.


Asunto(s)
Sistemas de Computación , Infecciones por Enterovirus/virología , Enterovirus/aislamiento & purificación , Técnicas de Diagnóstico Molecular , Reacción en Cadena de la Polimerasa/métodos , Infecciones del Sistema Respiratorio/virología , Enterovirus/clasificación , Enterovirus/genética , Infecciones por Enterovirus/epidemiología , Francia/epidemiología , Genotipo , Humanos , Recién Nacido , Pacientes Internos , Meningitis Aséptica/epidemiología , Meningitis Aséptica/virología , Cavidad Nasal/virología , Infecciones por Picornaviridae/epidemiología , Infecciones por Picornaviridae/virología , Estudios Prospectivos , ARN Viral/genética , ARN Viral/aislamiento & purificación , Infecciones del Sistema Respiratorio/epidemiología , Rhinovirus/clasificación , Rhinovirus/genética , Rhinovirus/aislamiento & purificación , Estaciones del Año
15.
FEMS Microbiol Ecol ; 97(11)2021 10 20.
Artículo en Inglés | MEDLINE | ID: mdl-34601598

RESUMEN

Agave lechuguilla has one of the widest distributions among other agave species in the Chihuahuan Desert. Their capacity to grow in poorly developed soils and harsh conditions has been related to their association with plant growth-promoting rhizobacteria. In this work, we explored how soil properties and plant growth stage influence the composition of the rhizobacterial communities, their interactions, and the enzymatic activity and abundance of nitrogen-fixing bacteria and organic phosphorus-mineralizing bacteria in two subregions of the Chihuahuan Desert. We found that mature plants of lechuguilla stimulated the activity and abundance of nutrient-improvement rhizobacteria, and these soil samples had a higher content of total organic carbon, ammonium (NH4) and nitrite + nitrate (NO2+NO3). Nutrient availability seems to be an essential driver of the bacterial community's structure since the genera with more connections (hubs) were those with known mechanisms related to the availability of nutrients, such as env. OPS17 (Bacteroidetes), Gemmatimonadaceae uncultured, S0134terrestrial group, BD211terrestrial group (Gemmatimonadetes), Chthoniobacteracea and Candidatus Udaeobacter (Verrucomicrobia). This work shows that the late growth stages of lechuguilla recruit beneficial bacteria that favor its establishment and tolerance to harsh conditions of the arid lands.


Asunto(s)
Agave , Rizosfera , Bacterias/genética , Nutrientes , Suelo , Microbiología del Suelo
16.
Eur Respir J ; 35(6): 1388-95, 2010 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-20032019

RESUMEN

We hypothesised that comparing the protein mixture in bronchoalveolar lavage fluid (BALF) between humans and mice may lead to mechanistic insights into common and divergent pathways that evolved in each species. BALF from four humans and six mice was pooled separately and underwent identical shotgun proteomic analysis. Functional and network analysis was applied to identify overlapping and distinct pathways enriched in the BALF. Follow-up experiments using Western analysis in unpooled BALF samples were performed. We identified 91 unique proteins in human and 117 unique proteins in mouse BALF samples. Functional analysis of the proteins revealed conservation of several key processes between the species, including defence response. Oxidative stress response, however, was selectively enriched only in mouse BALF. Differences in the expression of peroxiredoxin-1, a key member of the defence pathway against oxidative injury, were confirmed between normal human and mouse BALF and in models of lung injury. A computational proteomics approach of mouse and human BALF confirms the conservation of immune and defence-mediated pathways while highlighting differences in response to oxidative stress. These observations suggest that the use of mice models to study human lung disorders should be undertaken with an appreciation of interspecies variability.


Asunto(s)
Lesión Pulmonar Aguda/inmunología , Lesión Pulmonar Aguda/metabolismo , Líquido del Lavado Bronquioalveolar/inmunología , Estrés Oxidativo/inmunología , Proteómica/métodos , Animales , Modelos Animales de Enfermedad , Humanos , Hiperoxia/inmunología , Hiperoxia/metabolismo , Masculino , Ratones , Ratones Endogámicos C57BL , Peroxirredoxinas/metabolismo , Neumonía Estafilocócica/inmunología , Neumonía Estafilocócica/metabolismo , Especificidad de la Especie
17.
Int J Clin Pharmacol Ther ; 48(12): 847-53, 2010 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-21084040

RESUMEN

UNLABELLED: A previous study reported a 2- and 3-timepoint limited sampling strategy (LSS) model accurately predicted oral midazolam area under the concentration time curve (AUC), and thus cytochrome P450 (CYP) 3A activity. OBJECTIVE: This study evaluated whether the LSS models predict midazolam AUC during CYP3A baseline, inhibition and induction/activation. MATERIALS AND METHODS: Plasma midazolam concentrations from 106 healthy adults from 6 published studies were obtained where oral midazolam was co-administered alone or with ketoconazole, double-strength grapefruit juice, Ginkgo biloba extract, pleconaril, or rifampin. Observed and predicted midazolam AUCs were determined. Bias and precision of the LSS models were determined. RESULTS: Contrasting results were observed for the 2- and 3-timepoint LSS models in accurately predicting midazolam AUC during baseline CYP3A conditions. With the exception of 1 study (single dose, double-strength grapefruit juice), the 2- and 3-timepoint LSS models did not accurately predict midazolam AUC during conditions of CYP3A inhibition and induction/activation. CONCLUSION: The previously reported 2- and 3-timepoint oral midazolam LSS models are not applicable to the evaluated conditions of CYP3A baseline, inhibition, and induction/ activation.


Asunto(s)
Citocromo P-450 CYP3A/fisiología , Midazolam/farmacocinética , Administración Oral , Área Bajo la Curva , Inhibidores del Citocromo P-450 CYP3A , Activación Enzimática , Humanos
18.
Pathol Biol (Paris) ; 58(2): e51-7, 2010 Apr.
Artículo en Francés | MEDLINE | ID: mdl-20303676

RESUMEN

Seasonal flu is caused by influenza viruses A and B. These enveloped viruses have a genome made up of seven or eight RNA fragments. The different subtypes are determined by the nature of the two surface glycoproteins HA and NA. Seasonal flu is an epidemic wintertime illness occurring in temperate climate zones. Its epidemiology is linked to the great variability of the virus in time, necessitating an alert system that detects dominating circulating variants each year and that determines the vaccination composition. Clinical flu symptoms are not sufficiently specific to allow for diagnosis with virological tests. This is especially true during non-epidemic periods as well as in subjects older than 65 and younger than five. Children are especially vulnerable to influenza virus infections. Hospitalization occurs more frequently, the younger the child. In children younger than two years, the infection can be pauci-symptomatic and is sometimes detected from non-respiratory symptoms such as lethargy, convulsions, and dizziness. In all cases of respiratory syndrome compatible with influenza virus infection in hospitalized subjects, virological flu diagnosis is of utmost interest. Several tools are available to allow for direct viral detection in respiratory specimens: cell culture isolation, antigenic detection, RNA molecular detection. Choice of method is based on the characteristics of the test: sensibility, specificity, speed and ease of realization, and cost.


Asunto(s)
Gripe Humana/epidemiología , Adolescente , Adulto , Anciano , Antivirales/uso terapéutico , Niño , Preescolar , Genoma Viral , Humanos , Pruebas Inmunológicas , Lactante , Virus de la Influenza A/genética , Virus de la Influenza A/aislamiento & purificación , Virus de la Influenza A/fisiología , Virus de la Influenza B/genética , Virus de la Influenza B/aislamiento & purificación , Virus de la Influenza B/fisiología , Gripe Humana/diagnóstico , Gripe Humana/tratamiento farmacológico , Gripe Humana/virología , Persona de Mediana Edad , Estaciones del Año , Cultivo de Virus
19.
Front Plant Sci ; 11: 1028, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32765547

RESUMEN

Due to the environmental conditions presented in arid zones, it is expected to have a high influence of deterministic processes over the community assemblages. Symbiotic interactions with microorganisms could increase colonization and survival of plants in difficult conditions, independent of the plants physiological and morphological characteristics. In this context, the microbial communities associated to plants that inhabit these types of areas can be a good model to understand the community assembly processes. We investigated the influence of stochastic and deterministic processes in the assemblage of rhizosphere microbial communities of Agave lechuguilla and bulk soil on the Cuatro Cienegas Basin, a site known for its oligotrophic conditions. We hypothesize that rhizospheric microbial communities of A. lechuguilla differ from those of bulk soil as they differ in physicochemical properties of soil and biotic interactions, including not only the plant, but also their microbial co-occurrence networks, it is expected that microbial species usually critical for plant growth and health are more common in the rhizosphere, whereas in the bulk soil microbial species related to the resistance to abiotic stress are more abundant. In order to confirm this hypothesis, 16S rRNA gene was sequenced by Illumina from rhizospheric and bulk soil samples in two seasons, also the physicochemical properties of the soil were determined. Our results showed differences in bacterial diversity, community composition, potential functions, and interaction networks between the rhizosphere samples and the ones from bulk soil. Although community structure arises from a complex interplay between deterministic and stochastic forces, our results suggest that A. lechuguilla recruits specific rhizospheric microbes with functional traits that benefits the plant through growth promotion and nutrition. This selection follows principally a deterministic process that shapes the rhizospheric microbial communities, directed by the plant modifications around the roots but also subjected to the influence of other environmental variables, such as seasonality and soil properties. Interestingly, keystone taxa in the interactions networks, not necessarily belong to the most abundant taxonomic groups, but they have an important role by their functional traits and keeping the connections on the community network.

20.
Front Microbiol ; 11: 587, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32351467

RESUMEN

Humic substances are redox-active organic molecules, which play pivotal roles in several biogeochemical cycles due to their electron-transferring capacity involving multiple abiotic and microbial transformations. Based on the redox properties of humic substances, and the metabolic capabilities of microorganisms to reduce and oxidize them, we hypothesized that they could mediate the anaerobic oxidation of methane (AOM) coupled to the reduction of nitrous oxide (N2O) in wetland sediments. This study provides several lines of evidence indicating the coupling between AOM and the reduction of N2O through an extracellular electron transfer mechanism mediated by the redox active functional groups in humic substances (e.g., quinones). We found that the microbiota of a sediment collected from the Sisal wetland (Yucatán Peninsula, southeastern Mexico) was able to reduce N2O (4.6 ± 0.5 µmol N2O g sed. -1 day-1) when reduced humic substances were provided as electron donor in a close stoichiometric relationship. Furthermore, a microbial enrichment derived from the wetland sediment achieved simultaneous 13CH4 oxidation (1.3 ± 0.1 µmol 13CO2 g sed. -1 day-1) and N2O reduction (25.2 ± 0.5 µmol N2O g sed. -1 day-1), which was significantly dependent on the presence of humic substances as an extracellular electron shuttle. Taxonomic characterization based on 16S rRNA gene sequencing revealed Acinetobacter (a É£-proteobacterium), the Rice Cluster I from the Methanocellaceae and an uncultured archaeon from the Methanomicrobiaceae family as the microbes potentially involved in AOM linked to N2O reduction mediated by humic substances. The findings reported here suggest that humic substances might play an important role to prevent the emission of greenhouse gases (CH4 and N2O) from wetland sediments. Further efforts to evaluate the feasibility of this novel mechanism under the natural conditions prevailing in ecosystems must be considered in future studies.

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