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1.
Glob Chang Biol ; 29(21): 6040-6065, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37605971

RESUMO

Insect and disease outbreaks in forests are biotic disturbances that can profoundly alter ecosystem dynamics. In many parts of the world, these disturbance regimes are intensifying as the climate changes and shifts the distribution of species and biomes. As a result, key forest ecosystem services, such as carbon sequestration, regulation of water flows, wood production, protection of soils, and the conservation of biodiversity, could be increasingly compromised. Despite the relevance of these detrimental effects, there are currently no spatially detailed databases that record insect and disease disturbances on forests at the pan-European scale. Here, we present the new Database of European Forest Insect and Disease Disturbances (DEFID2). It comprises over 650,000 harmonized georeferenced records, mapped as polygons or points, of insects and disease disturbances that occurred between 1963 and 2021 in European forests. The records currently span eight different countries and were acquired through diverse methods (e.g., ground surveys, remote sensing techniques). The records in DEFID2 are described by a set of qualitative attributes, including severity and patterns of damage symptoms, agents, host tree species, climate-driven trigger factors, silvicultural practices, and eventual sanitary interventions. They are further complemented with a satellite-based quantitative characterization of the affected forest areas based on Landsat Normalized Burn Ratio time series, and damage metrics derived from them using the LandTrendr spectral-temporal segmentation algorithm (including onset, duration, magnitude, and rate of the disturbance), and possible interactions with windthrow and wildfire events. The DEFID2 database is a novel resource for many large-scale applications dealing with biotic disturbances. It offers a unique contribution to design networks of experiments, improve our understanding of ecological processes underlying biotic forest disturbances, monitor their dynamics, and enhance their representation in land-climate models. Further data sharing is encouraged to extend and improve the DEFID2 database continuously. The database is freely available at https://jeodpp.jrc.ec.europa.eu/ftp/jrc-opendata/FOREST/DISTURBANCES/DEFID2/.

2.
Anaerobe ; 82: 102762, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37481231

RESUMO

We present a case of bacteremia caused by Ruminococcus gnavus in an immunocompromised patient. R. gnavus is a Gram-positive strict anaerobe bacterium that forms chains. The bacteremia has been associated with an acute flare of ulcerative colitis. Anaerobic bacteremia is becoming increasingly frequent in patients with compromised gastrointestinal barrier. The role of the human microbiota and its alterations in the pathogenesis of immune-related diseases is an expanding area of interest. R. gnavus has been identified as a microorganism that may be responsible for the development of these diseases. The contribution of anaerobic bacteria to the pathogenesis of inflammatory bowel disease (IBD) is discussed, and cases reported up until 2023 were reviewed.


Assuntos
Bacteriemia , Colite Ulcerativa , Humanos , Bacteriemia/diagnóstico , Bacteriemia/microbiologia , Colite Ulcerativa/complicações , Colite Ulcerativa/diagnóstico , Hospedeiro Imunocomprometido , Ruminococcus
3.
J Pediatr Gastroenterol Nutr ; 74(6): 805-811, 2022 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-35192578

RESUMO

OBJECTIVES: Over the last several decades, there has been a tendency towards a predominance of less symptomatic forms of coeliac disease (CD) and an increase in the patient age at diagnosis. This study aimed to assess the clinical presentation and diagnostic process of paediatric CD in Spain. METHODS: A nationwide prospective, observational, multicentre registry of new paediatric CD cases was conducted from January 2011 to June 2017. The data regarding demographic variables, type of birth, breast-feeding history, family history of CD, symptoms, height and weight, associated conditions, serological markers, human leukocyte antigen (HLA) phenotype, and histopathological findings were collected. RESULTS: In total, 4838 cases (61% girls) from 73 centres were registered. The median age at diagnosis was 4 years. Gastrointestinal symptoms were detected in 71.4% of the patients, and diarrhoea was the most frequent symptom (45.9%). The most common clinical presentation was the classical form (65.1%) whereas 9.8% ofthe patients were asymptomatic. There was a trend towards an increase in the age at diagnosis, proportion of asymptomatic CD cases, and usage of anti-deamidated gliadin peptide antibodies and HLA typing for CD diagnosis. There was, however, a decreasing trend in the proportion of patients undergoing biopsies. Some of these significant trend changes may reflect the effects of the 2012 ESPGHAN diagnosis guidelines. CONCLUSIONS: Paediatric CD in Spain is evolving in the same direction as in the rest of Europe, although classical CD remains the most common presentation form, and the age at diagnosis remains relatively low.


Assuntos
Doença Celíaca , Sistema de Registros , Anticorpos , Doença Celíaca/complicações , Doença Celíaca/diagnóstico , Doença Celíaca/epidemiologia , Criança , Feminino , Gliadina , Humanos , Masculino , Estudos Prospectivos , Espanha/epidemiologia
4.
Clin Infect Dis ; 73(7): e2026-e2033, 2021 10 05.
Artigo em Inglês | MEDLINE | ID: mdl-32930720

RESUMO

BACKGROUND: Little is known about the effects of eradication of hepatitis C virus (HCV) on bone mineral density (BMD) and biomarkers of bone remodeling in human immunodeficiency virus (HIV)/HCV-coinfected patients. METHODS: We prospectively assessed standardized BMD (sBMD) at the lumbar spine and femoral neck, World Health Organization BMD categories at both sites, and plasma concentrations of soluble receptor activator of NF-κß ligand (sRANKL), and osteoprotegerin (OPG) at baseline (the date of initiation of anti-HCV therapy) and at 96 weeks. RESULTS: A total of 238 patients were included. The median age was 49.5 years, 76.5% were males, 48.3% had cirrhosis, 98.3% were on antiretroviral therapy, median CD4+ cell count was 527 cells/µL, and 86.6% had HIV-1 RNA <50 copies/mL. The prevalence of osteoporosis at baseline at the lumbar spine (LS) and femoral neck (FN) was 17.6% and 7.2%, respectively. Anti-HCV therapy comprised pegylated interferon (peg-IFN) and ribavirin (RBV) plus 1 direct-acting antiviral in 53.4%, peg-IFN/RBV in 34.5%, and sofosbuvir/RBV in 12.2%. A total of 145 (60.9%) patients achieved sustained virologic response (SVR). No significant effect of SVR was observed on sBMD for the interaction between time and SVR either in the LS (P = .801) or the FN (P = .911). Likewise, no significant effect of SVR was observed in plasma levels of sRANKL (P = .205), OPG (P = .249), or sRANKL/OPG ratio (P = .123) for the interaction between time and SVR. No significant correlation was found between fibrosis by transient elastography, and LS and FN sBMD, at baseline and week 96. CONCLUSIONS: SVR was not associated with significant changes in BMD nor biomarkers of bone remodeling in HIV/HCV-coinfected persons.


Assuntos
Coinfecção , Infecções por HIV , Hepatite C Crônica , Hepatite C , Antivirais/uso terapêutico , Densidade Óssea , Coinfecção/tratamento farmacológico , HIV , Infecções por HIV/complicações , Infecções por HIV/tratamento farmacológico , Hepacivirus , Hepatite C/complicações , Hepatite C/tratamento farmacológico , Hepatite C Crônica/tratamento farmacológico , Humanos , Interferon-alfa/uso terapêutico , Masculino , Pessoa de Meia-Idade , Polietilenoglicóis/uso terapêutico , Proteínas Recombinantes/uso terapêutico , Ribavirina/uso terapêutico
5.
Euro Surveill ; 26(25)2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-34169818

RESUMO

BackgroundRecent and reliable estimates on the prevalence of coinfection with human immunodeficiency virus (HIV) and hepatitis B virus (HBV) in Europe are lacking.AimLeveraged on a study designed to assess HIV/HCV coinfection prevalence, we assessed the prevalence of HIV/HBV coinfection in Spain in 2018 and compared the results with five similar studies performed since 2002.MethodsThis cross-sectional prevalence study was carried out in 43 centres, and patients were selected using simple random sampling. The reference population comprised 40,322 patients and the sample size were 1,690 patients.ResultsThe prevalence of HIV/HBV coinfection in Spain at the end of 2018 was 3.2%. The prevalence in 2002, 2009, 2015, 2016 and 2017 was 4.9%, 3.4%, 3%, 3.9% and 3%, respectively. Among the HIV/HBV-coinfected patients identified in 2018, 16.7% had cirrhosis according to transient elastography and 26.3% tested positive for antibodies against hepatitis D virus. All HIV/HBV-coinfected patients were receiving drugs with activity against HBV, and 97% of those tested for HBV DNA had an HBV DNA load < 80 IU/mL.ConclusionsThe prevalence of HIV/HBV coinfection in Spain remained stable at around 3% for a decade. Our data could facilitate the design of national programmes to control HBV infection and help identify areas of patient management that need improvement.


Assuntos
Coinfecção , Infecções por HIV , Hepatite B , Coinfecção/epidemiologia , Estudos Transversais , Europa (Continente) , Infecções por HIV/epidemiologia , Hepatite B/epidemiologia , Vírus da Hepatite B , Humanos , Prevalência , Espanha/epidemiologia
6.
J Environ Manage ; 293: 112785, 2021 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-34102498

RESUMO

Applying pruning residues in the lanes of olive groves has become a popular practice because it is economical and accrues benefits for soil and water management. This study presents an analysis of the impact of different rates of pruning residue on soil properties, in particular related with soil quality. Over 4 annual campaigns, chopped pruning residues used as a mulch were analyzed in terms of composition, coverage and moisture content to evaluate their effects on the amount of soil organic carbon (-10 cm and -20 cm) and CO2 emissions, temperature and moisture. The experiment was carried out in a super-intensive olive orchard in Cordoba (SE, Spain) and used four amounts of fresh pruning residue: 7.5 t ha⁻1(T1), 15.0 t ha⁻1 (T2) and 30.0 t ha⁻1 (T3), with a control T0 = 0.0 t ha1. Mulch mean leaf fraction was 46.0 ± 17.5% (±SD) and initial water content, 24.8 ± 8.6%. The mulching benefits for soil moisture were observed in amounts of pruning residue >7.5 t ha⁻1, which are only produced in super-intensive olive groves or in orchards with high tree densities. The low impact of the treatments on soil moisture was explained by the dramatic annual variations in residue moisture contents, caused by the regimes of high temperatures and rainfall-evapotranspiration deficits inherent to the Mediterranean Basin climate. Thus, the mulching capacity only resulted efficient when the residues were still humid in spring. In addition, 15.0 t ha⁻1 of pruning residues was the threshold to provide significant increases in soil organic carbon at depths of 0-20 cm. Thus, accumulating pruning residue in lanes at rates of over 15 t ha⁻1 (T2 and T3) is more convenient than a uniform distribution with lower amounts, due to the low mineralization rates occurring during warm seasons and the larger inputs of OM increasing the annual balance of SOC.


Assuntos
Agricultura , Olea , Solo , Agricultura/métodos , Carbono , Espanha
7.
Nature ; 502(7473): 672-6, 2013 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-24172979

RESUMO

The biogeochemical cycles of carbon (C), nitrogen (N) and phosphorus (P) are interlinked by primary production, respiration and decomposition in terrestrial ecosystems. It has been suggested that the C, N and P cycles could become uncoupled under rapid climate change because of the different degrees of control exerted on the supply of these elements by biological and geochemical processes. Climatic controls on biogeochemical cycles are particularly relevant in arid, semi-arid and dry sub-humid ecosystems (drylands) because their biological activity is mainly driven by water availability. The increase in aridity predicted for the twenty-first century in many drylands worldwide may therefore threaten the balance between these cycles, differentially affecting the availability of essential nutrients. Here we evaluate how aridity affects the balance between C, N and P in soils collected from 224 dryland sites from all continents except Antarctica. We find a negative effect of aridity on the concentration of soil organic C and total N, but a positive effect on the concentration of inorganic P. Aridity is negatively related to plant cover, which may favour the dominance of physical processes such as rock weathering, a major source of P to ecosystems, over biological processes that provide more C and N, such as litter decomposition. Our findings suggest that any predicted increase in aridity with climate change will probably reduce the concentrations of N and C in global drylands, but increase that of P. These changes would uncouple the C, N and P cycles in drylands and could negatively affect the provision of key services provided by these ecosystems.


Assuntos
Clima Desértico , Dessecação , Ecossistema , Geografia , Solo/química , Silicatos de Alumínio/análise , Biomassa , Carbono/análise , Carbono/metabolismo , Ciclo do Carbono , Argila , Mudança Climática , Modelos Teóricos , Nitrogênio/análise , Nitrogênio/metabolismo , Ciclo do Nitrogênio , Monoéster Fosfórico Hidrolases/análise , Monoéster Fosfórico Hidrolases/metabolismo , Fósforo/análise , Fósforo/metabolismo , Plantas/metabolismo
8.
Sensors (Basel) ; 19(1)2019 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-30609788

RESUMO

Although prostate cancer is one of the most common cancers in the male population, its basic biological function at a cellular level remains to be fully understood. This lack of in depth understanding of its physiology significantly hinders the development of new, targeted and more effective treatment strategies. Whilst electrophysiological studies can provide in depth analysis, the possibility of recording electrical activity in large populations of non-neuronal cells remains a significant challenge, even harder to address in the picoAmpere-range, which is typical of cellular level electrical activities. In this paper, we present the measurement and characterization of electrical activity of populations of prostate cancer cells PC-3, demonstrating for the first time a meaningful electrical pattern. The low noise system used comprises a multi-electrode array (MEA) with circular gold electrodes on silicon oxide substrates. The extracellular capacitive currents present two standard patterns: an asynchronous sporadic pattern and a synchronous quasi-periodic biphasic spike pattern. An amplitude of ±150 pA, a width between 50⁻300 ms and an inter-spike interval around 0.5 Hz characterize the quasi-periodic spikes. Our experiments using treatment of cells with Gd³âº, known as an inhibitor for the Ca²âº exchanges, suggest that the quasi-periodic signals originate from Ca²âº channels. After adding the Gd³âº to a population of living PC-3 cells, their electrical activity considerably decreased; once the culture was washed, thus eliminating the Gd³âº containing medium and addition of fresh cellular growth medium, the PC-3 cells recovered their normal electrical activity. Cellular viability plots have been carried out, demonstrating that the PC-3 cells remain viable after the use of Gd³âº, on the timescale of this experiment. Hence, this experimental work suggests that Ca²âº is significantly affecting the electrophysiological communication pattern among PC-3 cell populations. Our measuring platform opens up new avenues for real time and highly sensitive investigations of prostate cancer signalling pathways.


Assuntos
Fenômenos Eletrofisiológicos , Espaço Extracelular/fisiologia , Neoplasias da Próstata/ultraestrutura , Bloqueadores dos Canais de Cálcio/farmacologia , Eletricidade , Eletrodos , Fenômenos Eletrofisiológicos/efeitos dos fármacos , Gadolínio/farmacologia , Humanos , Ativação do Canal Iônico/efeitos dos fármacos , Masculino , Modelos Biológicos , Células PC-3 , Neoplasias da Próstata/metabolismo
9.
J Environ Manage ; 245: 245-254, 2019 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-31154171

RESUMO

The aim of the present study was to investigate the kinetics of methylparaben (MPB) and butylparaben (BPB) removal, two emerging pollutants with possible endocrine disrupting effects, from agricultural soil with and without amendment with compost from sewage sludge used as biostimulant. Compound removal is explained by a first-order kinetic model with half-life times of 6.5/6.7 days and 11.4/8.2 days, in presence/absence of compost, for MPB and BPB respectively. % R2 for the fitted model were higher than 96% in all cases. Additionally, isolation of bacteria capable to grow using MPB or BPB as carbon source was also carry out. Laboratory tests demonstrated the ability of these bacteria to biodegrade MPB and BPB from culture media in more than 95% in some cases. These strains showed high ability to biodegrade the compounds. Ten isolates, most of them related to Gram positive bacteria of the genus Bacillus, were identified by 16S rRNA gene sequencing. The study of the enzymatic activities of the isolates revealed both esterase (C4) and esterase-lipase activities.


Assuntos
Poluentes do Solo , Solo , Bactérias , Parabenos , RNA Ribossômico 16S , Esgotos , Microbiologia do Solo
10.
J Antimicrob Chemother ; 73(9): 2444-2451, 2018 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-29897573

RESUMO

Background: Concerns have been voiced over the capacity of deintensification strategies to preserve neurocognitive function and prevent neurocognitive impairment. Methods: We present the 96 week results of a neurocognitive substudy nested within the SALT clinical trial: a randomized, open-label, non-inferiority trial that compares whether atazanavir/ritonavir + lamivudine is non-inferior to atazanavir/ritonavir + two NRTIs in HIV-suppressed patients on stable triple therapy. A global deficit score (GDS) for five neurocognitive tasks was used to assess neurocognitive function. Changes in neurocognitive function (GDS value) were determined at weeks 48 and 96. The effect of atazanavir/ritonavir + lamivudine, adjusted for significant confounders, on the change in neurocognitive function was determined using analysis of covariance (ANCOVA) at week 96. Results: The per-protocol analysis included 92 participants (47 atazanavir/ritonavir + lamivudine and 45 atazanavir/ritonavir + two NRTIs). All baseline characteristics were comparable in both groups. At weeks 48 and 96, changes in GDS [week 48, atazanavir/ritonavir + lamivudine -0.3 (95% CI -0.5 to -0.1) versus atazanavir/ritonavir + two NRTIs -0.2 (95% CI -0.4 to 0.0), P = 0.39; week 96, atazanavir/ritonavir + lamivudine -0.3 (95% CI -0.5 to -0.1) versus atazanavir/ritonavir + two NRTIs -0.2 (95% CI -0.4 to -0.1); P = 0.471] were similar. This absence of differences was also observed in all cognitive tasks. Atazanavir/ritonavir + lamivudine did not impact the change in neurocognitive function at week 96; the adjusted effect of atazanavir/ritonavir + lamivudine on GDS change, considering atazanavir/ritonavir + two NRTIs as a reference, was 0.01 (95% CI -0.18 to 0.21) (P = 0.90). Conclusions: Neurocognitive function remained stable after 96 weeks, both in the atazanavir/ritonavir + lamivudine and in the atazanavir/ritonavir + two NRTIs arms, provided HIV remained suppressed.


Assuntos
Fármacos Anti-HIV/efeitos adversos , Sulfato de Atazanavir/efeitos adversos , Infecções por HIV/tratamento farmacológico , Lamivudina/efeitos adversos , Transtornos Neurocognitivos/epidemiologia , Ritonavir/efeitos adversos , Adulto , Fármacos Anti-HIV/administração & dosagem , Sulfato de Atazanavir/administração & dosagem , Feminino , Infecções por HIV/complicações , Humanos , Lamivudina/administração & dosagem , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Transtornos Neurocognitivos/induzido quimicamente , Ritonavir/administração & dosagem
11.
Glob Chang Biol ; 24(12): 5642-5654, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30239067

RESUMO

Despite their importance, how plant communities and soil microorganisms interact to determine the capacity of ecosystems to provide multiple functions simultaneously (multifunctionality) under climate change is poorly known. We conducted a common garden experiment using grassland species to evaluate how plant functional structure and soil microbial (bacteria and protists) diversity and abundance regulate soil multifunctionality responses to joint changes in plant species richness (one, three and six species) and simulated climate change (3°C warming and 35% rainfall reduction). The effects of species richness and climate on soil multifunctionality were indirectly driven via changes in plant functional structure and their relationships with the abundance and diversity of soil bacteria and protists. More specifically, warming selected for the larger and most productive plant species, increasing the average size within communities and leading to reductions in functional plant diversity. These changes increased the total abundance of bacteria that, in turn, increased that of protists, ultimately promoting soil multifunctionality. Our work suggests that cascading effects between plant functional traits and the abundance of multitrophic soil organisms largely regulate the response of soil multifunctionality to simulated climate change, and ultimately provides novel experimental insights into the mechanisms underlying the effects of biodiversity and climate change on ecosystem functioning.


Assuntos
Mudança Climática , Fenômenos Fisiológicos Vegetais , Microbiologia do Solo , Solo , Fenômenos Fisiológicos Bacterianos , Biodiversidade , Ecossistema , Solo/química
12.
Proc Natl Acad Sci U S A ; 112(51): 15684-9, 2015 12 22.
Artigo em Inglês | MEDLINE | ID: mdl-26647180

RESUMO

Soil bacteria and fungi play key roles in the functioning of terrestrial ecosystems, yet our understanding of their responses to climate change lags significantly behind that of other organisms. This gap in our understanding is particularly true for drylands, which occupy ∼41% of Earth´s surface, because no global, systematic assessments of the joint diversity of soil bacteria and fungi have been conducted in these environments to date. Here we present results from a study conducted across 80 dryland sites from all continents, except Antarctica, to assess how changes in aridity affect the composition, abundance, and diversity of soil bacteria and fungi. The diversity and abundance of soil bacteria and fungi was reduced as aridity increased. These results were largely driven by the negative impacts of aridity on soil organic carbon content, which positively affected the abundance and diversity of both bacteria and fungi. Aridity promoted shifts in the composition of soil bacteria, with increases in the relative abundance of Chloroflexi and α-Proteobacteria and decreases in Acidobacteria and Verrucomicrobia. Contrary to what has been reported by previous continental and global-scale studies, soil pH was not a major driver of bacterial diversity, and fungal communities were dominated by Ascomycota. Our results fill a critical gap in our understanding of soil microbial communities in terrestrial ecosystems. They suggest that changes in aridity, such as those predicted by climate-change models, may reduce microbial abundance and diversity, a response that will likely impact the provision of key ecosystem services by global drylands.


Assuntos
Mudança Climática , Ecossistema , Microbiologia do Solo , Concentração de Íons de Hidrogênio
13.
PLoS Pathog ; 11(6): e1004942, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26110623

RESUMO

African trypanosomiasis is a deadly neglected disease caused by the extracellular parasite Trypanosoma brucei. Current therapies are characterized by high drug toxicity and increasing drug resistance mainly associated with loss-of-function mutations in the transporters involved in drug import. The introduction of new antiparasitic drugs into therapeutic use is a slow and expensive process. In contrast, specific targeting of existing drugs could represent a more rapid and cost-effective approach for neglected disease treatment, impacting through reduced systemic toxicity and circumventing resistance acquired through impaired compound uptake. We have generated nanoparticles of chitosan loaded with the trypanocidal drug pentamidine and coated by a single domain nanobody that specifically targets the surface of African trypanosomes. Once loaded into this nanocarrier, pentamidine enters trypanosomes through endocytosis instead of via classical cell surface transporters. The curative dose of pentamidine-loaded nanobody-chitosan nanoparticles was 100-fold lower than pentamidine alone in a murine model of acute African trypanosomiasis. Crucially, this new formulation displayed undiminished in vitro and in vivo activity against a trypanosome cell line resistant to pentamidine as a result of mutations in the surface transporter aquaglyceroporin 2. We conclude that this new drug delivery system increases drug efficacy and has the ability to overcome resistance to some anti-protozoal drugs.


Assuntos
Resistência a Medicamentos/efeitos dos fármacos , Terapia de Alvo Molecular/métodos , Pentamidina/administração & dosagem , Tripanossomicidas/administração & dosagem , Tripanossomíase Africana/tratamento farmacológico , Animais , Anticorpos Antiprotozoários/administração & dosagem , Quitosana/administração & dosagem , Quitosana/farmacocinética , Modelos Animais de Doenças , Portadores de Fármacos/administração & dosagem , Portadores de Fármacos/farmacocinética , Ensaio de Desvio de Mobilidade Eletroforética , Feminino , Concentração Inibidora 50 , Camundongos , Camundongos Endogâmicos C57BL , Nanopartículas/uso terapêutico , Pentamidina/farmacocinética , Reação em Cadeia da Polimerase em Tempo Real , Tripanossomicidas/farmacocinética
14.
Pediatr Res ; 82(4): 658-664, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28678222

RESUMO

BackgroundThe impact of intrauterine and extrauterine growth on later insulin resistance and fat mass (FM) in very low birth weight (VLBW) infants is not well established. The aim of our study was to evaluate the effects of intrauterine and early/late extrauterine growth on later insulin resistance and body composition in VLBW infants from 6 months' corrected age (CA) to 36 months.MethodsProspective measurements of body composition by dual-energy X-ray absorptiometry and insulin resistance by homeostasis model assessment insulin resistance (HOMA-IR) along with other fasting plasma biochemistries were made in 95 VLBW infants at 6, 12, 18, and 24 months' CA and 36 months' postnatal age. Mixed-effect models were used to evaluate the effects of age, sex, maturation status, and Δweight SD score on percentage FM (PFM), FM index (FMI), fat-free mass index (FFMI), and HOMA-IR.ResultsPFM and FMI were negatively associated with a decrease in weight-SD scores from birth to 36 weeks' postmenstrual age (PMA; P=0.001) and from 36 weeks' PMA to 6 months' CA (P=0.003). PFM and FMI were higher in AGA than in small for gestational age (SGA) infants. HOMA-IR was not associated with the Δweight-SD scores in either period.ConclusionsCatch-down growth in terms of weight is associated with persistently lower adiposity but not insulin resistance up to 36 months of age.


Assuntos
Adiposidade , Desenvolvimento Infantil , Recém-Nascido Prematuro , Recém-Nascido de muito Baixo Peso/crescimento & desenvolvimento , Aumento de Peso , Absorciometria de Fóton , Fatores Etários , Biomarcadores/sangue , Peso ao Nascer , Glicemia/metabolismo , Pré-Escolar , Feminino , Idade Gestacional , Humanos , Lactente , Recém-Nascido , Recém-Nascido de muito Baixo Peso/sangue , Insulina/sangue , Resistência à Insulina , Masculino , Estudos Prospectivos
16.
AIDS Care ; 28(7): 890-7, 2016 07.
Artigo em Inglês | MEDLINE | ID: mdl-26981840

RESUMO

The wider availability of anti-retroviral treatment has brought about an improvement in the immunological situation of human immunodeficiency virus (HIV)-positive individuals, which in turn has led to significant reductions in AIDS-related morbidity and mortality and better quality of life for patients. However, the rate of diagnosis of new cases of HIV among the adult population is on the increase due to high-risk sexual behavior practices, particularly not using condoms, sexual relations with a large number of partners and starting sexual relations at a younger age, with unplanned pregnancies and sexually transmitted infections (STIs), including HIV. For this reason, public health managers have invested considerable effort in recent years in creating STI and HIV prevention programs. Yet, in spite of the implementation of measures for reducing the rates of infection, few studies have been published in Spain comparing individuals living with HIV with the general population about cognitive variables and the link between these variables and high-risk sexual behavior. The objective was to compare a group of individuals living with HIV with another group from the general population in terms of cognitive variables (knowledge about STIs and HIV, concern about STI/HIV and pregnancy, self-efficacy to refuse sexual relations and resilience) and sexual behavior. The sample consisted of 318 adults, 159 were from the general population and 159 were individuals living with HIV. Individuals living with HIV had higher scores for concern about HIV/AIDS, STIs, pregnancy and knowledge of STI/HIV compared with the general population. We concluded that uninfected people who had low and high level of concern about HIV/AIDS began having anal sex at a younger age than those with a medium level of concern. Overall, results indicate that the concern about HIV/AIDS should be addressed in preventive health interventions to minimize the risks of sexual behavior.


Assuntos
Cognição , Infecções por HIV , Complicações Infecciosas na Gravidez , Qualidade de Vida , Comportamento Sexual/psicologia , Sexo sem Proteção , Adulto , Preservativos/estatística & dados numéricos , Feminino , Infecções por HIV/diagnóstico , Infecções por HIV/epidemiologia , Infecções por HIV/prevenção & controle , Infecções por HIV/psicologia , Humanos , Masculino , Avaliação das Necessidades , Gravidez , Complicações Infecciosas na Gravidez/diagnóstico , Complicações Infecciosas na Gravidez/epidemiologia , Complicações Infecciosas na Gravidez/prevenção & controle , Complicações Infecciosas na Gravidez/psicologia , Serviços Preventivos de Saúde/métodos , Serviços Preventivos de Saúde/normas , Assunção de Riscos , Autoeficácia , Parceiros Sexuais/psicologia , Espanha/epidemiologia , Sexo sem Proteção/prevenção & controle , Sexo sem Proteção/psicologia , Sexo sem Proteção/estatística & dados numéricos
17.
Enferm Infecc Microbiol Clin ; 34(8): 477-83, 2016 Oct.
Artigo em Espanhol | MEDLINE | ID: mdl-26656792

RESUMO

INTRODUCTION: The aim of the study was to assess whether the penetration of antibiotics is affected by decreased tissue perfusion in patients with limb ischaemia, thus reducing its concentration in tissues below the minimum inhibitory concentration (MIC) breakpoints of antibiotics for different microorganisms. METHODS: Prospective study. Candidates for major amputation with critical lower limb ischaemia and an infection on antibiotic treatment, were included. Three levels of perfusion in the lower limb were determined by measuring the transcutaneous oxygen pressure (TcPO2). A central line blood specimen, as well as biopsies of the skin, muscle, and bone, were taken at each perfusion level. The antibiotic concentration was determined using HPLC. RESULTS: The total number of cases was 61 (46 patients): 6 clindamycin, 9 vancomycin, 8 linezolid, 18 levofloxacin, 9 ceftazidime, and 11 meropenem. Statistically significant differences were found in TcPO2 at all levels (ANOVA, P=.000). The vancomycin, levofloxacin and ceftazidime skin concentration depends on perfusion. Vancomycin and levofloxacin diffusion in bone is worse than in other tissues. Ceftazidime concentration does not exceed the MIC breakpoint of Pseudomonas aeruginosa in ischaemic tissues. CONCLUSIONS: Meropenem and linezolid diffuse in all tissues, regardless of perfusion, reaching concentrations above the MIC of the target microorganisms, ensuring its effectiveness in ischaemic tissues.


Assuntos
Antibacterianos/farmacocinética , Isquemia/metabolismo , Extremidade Inferior/irrigação sanguínea , Idoso , Ceftazidima , Cromatografia Líquida de Alta Pressão , Clindamicina/farmacocinética , Feminino , Humanos , Levofloxacino/farmacocinética , Linezolida/farmacocinética , Masculino , Meropeném , Testes de Sensibilidade Microbiana , Estudos Prospectivos , Pele/metabolismo , Tienamicinas/farmacocinética , Vancomicina/farmacocinética
18.
Ecol Lett ; 18(8): 790-798, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26032242

RESUMO

Intransitive competition networks, those in which there is no single best competitor, may ensure species coexistence. However, their frequency and importance in maintaining diversity in real-world ecosystems remain unclear. We used two large data sets from drylands and agricultural grasslands to assess: (1) the generality of intransitive competition, (2) intransitivity-richness relationships and (3) effects of two major drivers of biodiversity loss (aridity and land-use intensification) on intransitivity and species richness. Intransitive competition occurred in > 65% of sites and was associated with higher species richness. Intransitivity increased with aridity, partly buffering its negative effects on diversity, but was decreased by intensive land use, enhancing its negative effects on diversity. These contrasting responses likely arise because intransitivity is promoted by temporal heterogeneity, which is enhanced by aridity but may decline with land-use intensity. We show that intransitivity is widespread in nature and increases diversity, but it can be lost with environmental homogenisation.


Assuntos
Biodiversidade , Modelos Biológicos , Plantas/classificação , Agricultura , Mudança Climática , Alemanha , Pradaria
19.
BMC Microbiol ; 15: 245, 2015 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-26518881

RESUMO

BACKGROUND: Despite widespread use, optimum choice of antimicrobial agents, concentrations, combinations and exposure times have not been determined for antibiotic lock technique (ALT). Our objective was to evaluate the efficacy of different antibiotic combinations using an in vitro model of catheter-related infection. Daptomycin (DAP) 5 mg/mL, teicoplanin (TEC) 5 mg/mL, both alone and combined with gentamicin (GM) 2.5 mg/mL, clarythromycin (CLA) 5 mg/mL or ethanol 35 % were evaluated against four clinical strains of methicillin resistant coagulase negative staphylococci. Lock solutions were renewed every 24 h. RESULTS: After 72 h catheters were reincubated with culture media to investigate bacterial regrowth. All antibiotic combinations resulted in significant reductions (p < 0.05) of Log(10) cfu/mL at 72 h for both organisms compared with controls. DAP resulted in significant reductions of Log(10) for all organism versus TEC (p = 0.001). Only DAP reached the limit of detection at 72 h, however did not prevent regrowth after 24 h of ALT removal. DAP + Ethanol and TEC + ethanol eradicated biofilm at 72 h, but only DAP + ethanol (against all strains) and DAP + CLA (against two strains) prevented regrowth at 24 h after ALT removal. CONCLUSIONS: Based on these data, ALT with DAP + ethanol and DAP + CLA should be explored in clinical trials.


Assuntos
Antibacterianos/farmacologia , Quimioterapia Combinada/métodos , Soluções Isotônicas/farmacologia , Resistência a Meticilina/efeitos dos fármacos , Staphylococcus epidermidis/efeitos dos fármacos , Antibacterianos/uso terapêutico , Biofilmes/efeitos dos fármacos , Catéteres/microbiologia , Claritromicina/farmacologia , Daptomicina/farmacologia , Etanol/farmacologia , Gentamicinas/farmacologia , Humanos , Técnicas In Vitro , Soluções Isotônicas/química , Soluções Isotônicas/uso terapêutico , Testes de Sensibilidade Microbiana , Staphylococcus epidermidis/crescimento & desenvolvimento , Teicoplanina/farmacologia , Vancomicina/farmacologia
20.
New Phytol ; 206(2): 660-71, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25615801

RESUMO

We used a functional trait-based approach to assess the impacts of aridity and shrub encroachment on the functional structure of Mediterranean dryland communities (functional diversity (FD) and community-weighted mean trait values (CWM)), and to evaluate how these functional attributes ultimately affect multifunctionality (i.e. the provision of several ecosystem functions simultaneously). Shrub encroachment (the increase in the abundance/cover of shrubs) is a major land cover change that is taking place in grasslands worldwide. Studies conducted on drylands have reported positive or negative impacts of shrub encroachment depending on the functions and the traits of the sprouting or nonsprouting shrub species considered. FD and CWM were equally important as drivers of multifunctionality responses to both aridity and shrub encroachment. Size traits (e.g. vegetative height or lateral spread) and leaf traits (e.g. specific leaf area and leaf dry matter content) captured the effect of shrub encroachment on multifunctionality with a relative high accuracy (r(2)  = 0.63). FD also improved the resistance of multifunctionality along the aridity gradient studied. Maintaining and enhancing FD in plant communities may help to buffer negative effects of ongoing global environmental change on dryland multifunctionality.


Assuntos
Modelos Biológicos , Plantas/metabolismo , Adaptação Biológica , Biodiversidade , Ecossistema , Região do Mediterrâneo , Folhas de Planta/metabolismo , Fenômenos Fisiológicos Vegetais , Água/fisiologia
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