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BACKGROUND: Current guidelines recommend treating hypertension in patients with peripheral artery disease (PAD) to reduce the risk of cardiac events and stroke, but the effect of reducing blood pressure on lower extremity PAD events is largely unknown. We investigated the association of blood pressure with lower extremity PAD events using data from the ALLHAT trial (Antihypertensive and Lipid-Lowering Treatment to Prevent Heart Attack Trial). METHODS: ALLHAT investigated the effect of different antihypertensive medication classes (chlorthalidone, amlodipine, lisinopril, or doxazosin) on cardiovascular events. With the use of these data, the primary outcome in our analysis was time to first lower extremity PAD event, defined as PAD-related hospitalization, procedures, medical treatment, or PAD-related death. Given the availability of longitudinal standardized blood pressure measurements, we analyzed systolic blood pressure (SBP), diastolic blood pressure (DBP), and pulse pressure as time-varying categorical variables (reference categories 120-129 mm Hg for SBP, 70-79 mm Hg for DBP, and 45-54 mm Hg for pulse pressure) in separate models. We used extended Cox regression with death as a competing risk to calculate the association of each blood pressure component with PAD events, and report the results as subdistribution hazard ratios and 95% CIs. RESULTS: The present analysis included 33 357 patients with an average age of 67.4 years, 53.1% men, 59.7% white race, and 36.2% with diabetes mellitus. The median baseline blood pressure was 146/84 mm Hg. Participants were followed for a median of 4.3 (interquartile range, 3.6-5.3) years, during which time 1489 (4.5%) had a lower extremity PAD event, and 4148 (12.4%) died. In models adjusted for demographic and clinical characteristics, SBP <120 mm Hg was associated with a 26% (CI, 5%-52%; P=0.015) higher hazard and SBP≥160 mm Hg was associated with a 21% (CI, 0%-48%; P=0.050) higher hazard for a PAD event, in comparison with SBP 120 to 129 mm Hg. In contrast, lower, but not higher, DBP was associated with a higher hazard of PAD events: for DBP <60 mm Hg (hazard ratio, 1.72; CI, 1.38-2.16). Pulse pressure had a U-shaped association with PAD events. CONCLUSIONS: In this reanalysis of data from ALLHAT, we found a higher rate of lower extremity PAD events with higher and lower SBP and pulse pressure and with lower DBP. Given the recent revised blood pressure guidelines advocating lower SBP targets for overall cardiovascular risk reduction, further refinement of optimal blood pressure targets specific to PAD is needed. CLINICAL TRIAL REGISTRATION: URL: https://www.clinicaltrials.gov . Unique identifier: NCT00000542.
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Anti-Hipertensivos/uso terapêutico , Pressão Sanguínea/efeitos dos fármacos , Hipertensão/tratamento farmacológico , Extremidade Inferior/irrigação sanguínea , Doença Arterial Periférica/fisiopatologia , Idoso , Anti-Hipertensivos/efeitos adversos , Determinação da Pressão Arterial , Feminino , Humanos , Hipertensão/diagnóstico , Hipertensão/mortalidade , Hipertensão/fisiopatologia , Masculino , Pessoa de Meia-Idade , Estudos Multicêntricos como Assunto , Doença Arterial Periférica/diagnóstico , Doença Arterial Periférica/mortalidade , Doença Arterial Periférica/terapia , Ensaios Clínicos Controlados Aleatórios como Assunto , Medição de Risco , Fatores de Risco , Fatores de Tempo , Resultado do TratamentoRESUMO
INTRODUCTION: Reducing long length of stay (LLOS, or inpatient stays lasting over 30 days) is an important way for hospitals to improve cost efficiency, bed availability and health outcomes. Discharge delays can cost hundreds to thousands of dollars per patient, and LLOS represents a burden on bed availability for other potential patients. However, most research studies investigating discharge barriers are not LLOS-specific. Of those that do, nearly all are limited by further patient subpopulation focus or small sample size. To our knowledge, our study is the first to describe LLOS discharge barriers in an entire Department of Medicine. METHODS: We conducted a chart review of 172 LLOS patients in the Department of Medicine at an academic tertiary care hospital and quantified the most frequent causes of delay as well as factors causing the greatest amount of delay time. We also interviewed healthcare staff for their perceptions on barriers to discharge. RESULTS: Discharge site coordination was the most frequent cause of delay, affecting 56% of patients and accounting for 80% of total non-medical postponement days. Goals of care issues and establishment of follow-up care were the next most frequent contributors to delay. CONCLUSION: Together with perspectives from interviewed staff, these results highlight multiple different areas of opportunity for reducing LLOS and maximising the care capacity of inpatient hospitals.
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Doença Iatrogênica/prevenção & controle , Tempo de Internação/estatística & dados numéricos , Alta do Paciente/estatística & dados numéricos , Centros de Atenção Terciária , Adulto , Idoso , Idoso de 80 Anos ou mais , Ocupação de Leitos , Análise Custo-Benefício , Feminino , Humanos , Doença Iatrogênica/economia , Tempo de Internação/economia , Masculino , Pessoa de Meia-Idade , Avaliação de Processos e Resultados em Cuidados de Saúde , Alta do Paciente/economia , Centros de Atenção Terciária/economia , Centros de Atenção Terciária/organização & administração , Fatores de Tempo , Adulto JovemRESUMO
The Antarctic Dry Valleys are unable to support higher plant and animal life and so microbial communities dominate biotic ecosystem processes. Soil communities are well characterized, but rocky surfaces have also emerged as a significant microbial habitat. Here, we identify extensive colonization of weathered granite on a landscape scale by chasmoendolithic microbial communities. A transect across north-facing and south-facing slopes plus valley floor moraines revealed 30-100 % of available substrate was colonized up to an altitude of 800 m. Communities were assessed at a multidomain level and were clearly distinct from those in surrounding soils and other rock-inhabiting cryptoendolithic and hypolithic communities. All colonized rocks were dominated by the cyanobacterial genus Leptolyngbya (Oscillatoriales), with heterotrophic bacteria, archaea, algae, and fungi also identified. Striking patterns in community distribution were evident with regard to microclimate as determined by aspect. Notably, a shift in cyanobacterial assemblages from Chroococcidiopsis-like phylotypes (Pleurocapsales) on colder-drier slopes, to Synechococcus-like phylotypes (Chroococcales) on warmer-wetter slopes. Greater relative abundance of known desiccation-tolerant bacterial taxa occurred on colder-drier slopes. Archaeal phylotypes indicated halotolerant taxa and also taxa possibly derived from nearby volcanic sources. Among the eukaryotes, the lichen photobiont Trebouxia (Chlorophyta) was ubiquitous, but known lichen-forming fungi were not recovered. Instead, fungal assemblages were dominated by ascomycetous yeasts. We conclude that chasmoendoliths likely constitute a significant geobiological phenomenon at lower elevations in granite-dominated Antarctic Dry Valley systems.
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Biodiversidade , Ecossistema , Microbiologia do Solo , Regiões Antárticas , Archaea/classificação , Archaea/genética , Bactérias/classificação , Bactérias/genética , Cianobactérias/classificação , Cianobactérias/genética , Fungos/classificação , Fungos/genética , Líquens/classificação , Líquens/genética , Consórcios Microbianos , Microclima , Filogenia , Análise de Sequência de DNA , Dióxido de SilícioRESUMO
The huhu beetle (Prionoplus reticularis) is the largest endemic beetle found throughout Aotearoa New Zealand, and is characterised by feeding on wood during its larval stage. It has been hypothesised that its gut microbiome plays a fundamental role in the degradation of wood. To explore this idea we examined the fungal and bacterial community composition of huhu grubs' frass, using amplicon sequencing. Grubs were reared on an exclusive diet of either a predominantly cellulose source (cotton) or lignocellulose source (pine) for 4 months; subsequently a diet switch was performed and the grubs were grown for another 4 months. The fungal community of cellulose-reared huhu grubs was abundant in potential cellulose degraders, contrasting with the community of lignocellulose-reared grubs, which showed abundant potential soft rot fungi, yeasts, and hemicellulose and cellulose degraders. Cellulose-reared grubs showed a less diverse fungal community, however, diet switch from cellulose to lignocellulose resulted in a change in community composition that showed grubs were still capable of utilising this substrate. Conversely, diet seemed to have a limited influence on huhu grub gut bacterial communities.
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Besouros , Microbioma Gastrointestinal , Lignina , Microbioma Gastrointestinal/fisiologia , Microbioma Gastrointestinal/efeitos dos fármacos , Animais , Lignina/metabolismo , Besouros/microbiologia , Celulose/metabolismo , Dieta , Nova Zelândia , Fungos/genética , Fungos/metabolismo , Bactérias/genética , Bactérias/classificação , Bactérias/metabolismoRESUMO
BACKGROUND: Isolating the effects of deterministic variables (e.g., physicochemical conditions) on soil microbial communities from those of neutral processes (e.g., dispersal) remains a major challenge in microbial ecology. In this study, we disturbed soil microbial communities of two McMurdo Dry Valleys of Antarctica exhibiting distinct microbial biogeographic patterns, both devoid of aboveground biota and different in macro- and micro-physicochemical conditions. We modified the availability of water, nitrogen, carbon, copper ions, and sodium chloride salts in a laboratory-based experiment and monitored the microbial communities for up to two months. Our aim was to mimic a likely scenario in the near future, in which similar selective pressures will be applied to both valleys. We hypothesized that, given their unique microbial communities, the two valleys would select for different microbial populations when subjected to the same disturbances. RESULTS: The two soil microbial communities, subjected to the same disturbances, did not respond similarly as reflected in both 16S rRNA genes and transcripts. Turnover of the two microbial communities showed a contrasting response to the same environmental disturbances and revealed different potentials for adaptation to change. These results suggest that the heterogeneity between these microbial communities, reflected in their strong biogeographic patterns, was maintained even when subjected to the same selective pressure and that the 'rare biosphere', at least in these samples, were deeply divergent and did not act as a reservoir for microbiota that enabled convergent responses to change in environmental conditions. CONCLUSIONS: Our findings strongly support the occurrence of endemic microbial communities that show a structural resilience to environmental disturbances, spanning a wide range of physicochemical conditions. In the highly arid and nutrient-limited environment of the Dry Valleys, these results provide direct evidence of microbial biogeographic patterns that can shape the communities' response in the face of future environmental changes.
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Allopatric speciation has been difficult to examine among microorganisms, with prior reports of endemism restricted to sub-genus level taxa. Previous microbial community analysis via 16S rRNA gene sequencing of 925 geothermal springs from the Taupo Volcanic Zone (TVZ), Aotearoa-New Zealand, revealed widespread distribution and abundance of a single bacterial genus across 686 of these ecosystems (pH 1.2-9.6 and 17.4-99.8 °C). Here, we present evidence to suggest that this genus, Venenivibrio (phylum Aquificota), is endemic to Aotearoa-New Zealand. A specific environmental niche that increases habitat isolation was identified, with maximal read abundance of Venenivibrio occurring at pH 4-6, 50-70 °C, and low oxidation-reduction potentials. This was further highlighted by genomic and culture-based analyses of the only characterised species for the genus, Venenivibrio stagnispumantis CP.B2T, which confirmed a chemolithoautotrophic metabolism dependent on hydrogen oxidation. While similarity between Venenivibrio populations illustrated that dispersal is not limited across the TVZ, extensive amplicon, metagenomic, and phylogenomic analyses of global microbial communities from DNA sequence databases indicates Venenivibrio is geographically restricted to the Aotearoa-New Zealand archipelago. We conclude that geographic isolation, complemented by physicochemical constraints, has resulted in the establishment of an endemic bacterial genus.
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Microbiota , Nova Zelândia , RNA Ribossômico 16S/genética , Filogenia , MetagenomaRESUMO
Little is known about protists at deep-sea hydrothermal vents. The vent sites at Guaymas Basin in the Gulf of California are characterized by dense mats of filamentous pigmented or nonpigmented Beggiatoa that serve as markers of subsurface thermochemical gradients. We constructed 18S rRNA libraries to investigate ciliate assemblages in Beggiatoa mats and from bare sediments at the Guaymas vent site. Results indicated a high diversity of ciliates, with 156 operational taxonomic units identified in 548 sequences. Comparison between mat environments demonstrated that ciliate and bacterial assemblages from pigmented mats, nonpigmented mats, and bare sediments were significantly different and highly correlated with bacterial assemblages. Neither bacterial nor ciliate assemblages were correlated with environmental factors. The most abundant ciliates at Guaymas were more likely to be represented in clone libraries from other hydrothermal, deep-sea, and/or anoxic or microaerophilic environments, supporting the hypothesis that these ciliate species are broadly distributed. The orange mat environment included a higher proportion of ciliate sequences that were more similar to those from other environmental studies than to cultured ciliate species, whereas clone libraries from bare sediments included sequences that were the most highly divergent from all other sequences and may represent species that are endemic to Guaymas.
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Biodiversidade , Cilióforos/classificação , Cilióforos/isolamento & purificação , Sedimentos Geológicos/parasitologia , Fontes Hidrotermais/parasitologia , Cilióforos/genética , Análise por Conglomerados , DNA de Protozoário/química , DNA de Protozoário/genética , DNA Ribossômico/química , DNA Ribossômico/genética , Genes de RNAr , Dados de Sequência Molecular , Filogenia , RNA de Protozoário/genética , RNA Ribossômico 18S/genética , Análise de Sequência de DNARESUMO
Antarctic ecosystems are under increasing anthropogenic pressure, but efforts to predict the responses of Antarctic biodiversity to environmental change are hindered by considerable data challenges. Here, we illustrate how novel data capture technologies provide exciting opportunities to sample Antarctic biodiversity at wider spatiotemporal scales. Data integration frameworks, such as point process and hierarchical models, can mitigate weaknesses in individual data sets, improving confidence in their predictions. Increasing process knowledge in models is imperative to achieving improved forecasts of Antarctic biodiversity, which can be attained for data-limited species using hybrid modelling frameworks. Leveraging these state-of-the-art tools will help to overcome many of the data scarcity challenges presented by the remoteness of Antarctica, enabling more robust forecasts both near- and long-term.
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Biodiversidade , Ecossistema , Regiões Antárticas , Previsões , Mudança ClimáticaRESUMO
The dispersion of microorganisms through the atmosphere is a continual and essential process that underpins biogeography and ecosystem development and function. Despite the ubiquity of atmospheric microorganisms globally, specific knowledge of the determinants of atmospheric microbial diversity at any given location remains unresolved. Here we describe bacterial diversity in the atmospheric boundary layer and underlying soil at twelve globally distributed locations encompassing all major biomes, and characterise the contribution of local and distant soils to the observed atmospheric community. Across biomes the diversity of bacteria in the atmosphere was negatively correlated with mean annual precipitation but positively correlated to mean annual temperature. We identified distinct non-randomly assembled atmosphere and soil communities from each location, and some broad trends persisted across biomes including the enrichment of desiccation and UV tolerant taxa in the atmospheric community. Source tracking revealed that local soils were more influential than distant soil sources in determining observed diversity in the atmosphere, with more emissive semi-arid and arid biomes contributing most to signatures from distant soil. Our findings highlight complexities in the atmospheric microbiota that are relevant to understanding regional and global ecosystem connectivity.
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Ecossistema , Microbiota , Solo , Bactérias , Atmosfera , Temperatura , Microbiologia do SoloRESUMO
Submarine hydrothermal vents are model systems for the Archaean Earth environment, and some sites maintain conditions that may have favored the formation and evolution of cellular life. Vents are typified by rapid fluctuations in temperature and redox potential that impose a strong selective pressure on resident microbial communities. Nautilia profundicola strain Am-H is a moderately thermophilic, deeply-branching Epsilonproteobacterium found free-living at hydrothermal vents and is a member of the microbial mass on the dorsal surface of vent polychaete, Alvinella pompejana. Analysis of the 1.7-Mbp genome of N. profundicola uncovered adaptations to the vent environment--some unique and some shared with other Epsilonproteobacterial genomes. The major findings included: (1) a diverse suite of hydrogenases coupled to a relatively simple electron transport chain, (2) numerous stress response systems, (3) a novel predicted nitrate assimilation pathway with hydroxylamine as a key intermediate, and (4) a gene (rgy) encoding the hallmark protein for hyperthermophilic growth, reverse gyrase. Additional experiments indicated that expression of rgy in strain Am-H was induced over 100-fold with a 20 degrees C increase above the optimal growth temperature of this bacterium and that closely related rgy genes are present and expressed in bacterial communities residing in geographically distinct thermophilic environments. N. profundicola, therefore, is a model Epsilonproteobacterium that contains all the genes necessary for life in the extreme conditions widely believed to reflect those in the Archaean biosphere--anaerobic, sulfur, H2- and CO2-rich, with fluctuating redox potentials and temperatures. In addition, reverse gyrase appears to be an important and common adaptation for mesophiles and moderate thermophiles that inhabit ecological niches characterized by rapid and frequent temperature fluctuations and, as such, can no longer be considered a unique feature of hyperthermophiles.
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Adaptação Fisiológica/genética , Epsilonproteobacteria/genética , Genoma Bacteriano , Archaea/genética , Archaea/crescimento & desenvolvimento , Carbono/metabolismo , Replicação do DNA , DNA Arqueal/metabolismo , Ecossistema , Epsilonproteobacteria/crescimento & desenvolvimento , Nitrogênio/metabolismo , Oxirredução , Filogenia , Água do Mar , Transdução de Sinais , Enxofre/metabolismo , TemperaturaRESUMO
Improved techniques in microvascular surgery over the last several decades have led to the increased use of free tissue transfers as a mode of reconstructing difficult problems with a high success rate. However, undiagnosed thrombophilias have been associated with microsurgery free flap failures. We present a case of successful free tissue transfer in a patient with lupus anticoagulant and review the literature.
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Retalhos de Tecido Biológico , Extremidade Inferior/cirurgia , Inibidor de Coagulação do Lúpus/sangue , Trombose Venosa/prevenção & controle , Acidentes de Trânsito , Adulto , Algoritmos , Anticoagulantes/uso terapêutico , Dextranos/uso terapêutico , Humanos , Extremidade Inferior/lesões , Masculino , Microcirurgia , Motocicletas , Músculo Esquelético/transplante , Trombose Venosa/etiologia , Varfarina/uso terapêuticoRESUMO
Bariatric surgery for the treatment of obesity, first introduced in the 1950s and 1960s, is now relatively commonplace. Often patients will first have an adjustable gastric band inserted, as this does not require altering or removing parts of the gastrointestinal tract. This procedure is associated with short hospital stays and quick recoveries and may be adjusted without further surgery. Typically only after banding fails mechanically or fails to bring about a satisfactory reduction in body mass index (BMI) do patients undergo further bariatric procedures which involve altering or removing parts of the gastrointestinal tract. Recent research has suggested that gastric banding is associated with greater weight reduction results as a secondary or follow-up procedure following a failed initial bariatric surgery. Here we report the case of a 43-year-old female with a history of cryptogenic organizing pneumonitis, gastroesophageal reflux disease (GERD), asthma, obesity, and prior sleeve gastrectomy who underwent a laparoscopic gastric band insertion to revise the prior sleeve gastrectomy, in reverse of the typical sequence of bariatric surgeries.
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Intraoperative hypothermia increases patient morbidity, including bleeding and infection risk. Neurosurgical intraoperative magnetic resonance imaging (iMRI) can lead to hypothermia from patient exposure and low ambient temperature in the MRI suite. This quality improvement project aimed to reduce the risk of hypothermia during pediatric neurosurgery laser ablation procedures with iMRI. The primary aim was to increase the mean lowest core temperature in pediatric patients with epilepsy during iMRI procedures by 1 °C from a baseline mean lowest core temperature of 34.2 ± 1.2 °C within 10 months and sustain for 10 months. Methods: This report is a single-institution quality improvement project from March 2019 to June 2021, with 21 patients treated at a pediatric hospital. After identifying key drivers, temperature-warming interventions were instituted to decrease hypothermia among patients undergoing iMRI during neurosurgery procedures. A multidisciplinary team of physicians, nurses, and MRI technologists convened for huddles before each case. Interventions included prewarmed operating rooms (ORs), blanket coverings, MRI table and room; forced-air blanket warming, temperature monitoring in the OR and iMRI environments; and the MRI fan turned off. Results: Data were analyzed for five patients before and nine patients after the institution of the temperature-warming elements. The sustainment period included 15 patients. The mean lowest intraoperative temperature rose from 34.2 ± 1.3 °C in the preintervention period to 35.5 ± 0.6 °C in sustainment (P = 0.004). Conclusion: Hybrid OR and MRI procedures increase hypothermia risk, which increases patient morbidity. Implementation of a multidisciplinary, multi-item strategy for patient warming mitigates the risk.
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Antarctic deserts, such as the McMurdo Dry Valleys (MDV), represent extremely cold and dry environments. Consequently, MDV are suitable for studying the environment limits on the cycling of key elements that are necessary for life, like nitrogen. The spatial distribution and biogeochemical drivers of nitrogen-cycling pathways remain elusive in the Antarctic deserts because most studies focus on specific nitrogen-cycling genes and/or organisms. In this study, we analyzed metagenome and relevant environmental data of 32 MDV soils to generate a complete picture of the nitrogen-cycling potential in MDV microbial communities and advance our knowledge of the complexity and distribution of nitrogen biogeochemistry in these harsh environments. We found evidence of nitrogen-cycling genes potentially capable of fully oxidizing and reducing molecular nitrogen, despite the inhospitable conditions of MDV. Strong positive correlations were identified between genes involved in nitrogen cycling. Clear relationships between nitrogen-cycling pathways and environmental parameters also indicate abiotic and biotic variables, like pH, water availability, and biological complexity that collectively impose limits on the distribution of nitrogen-cycling genes. Accordingly, the spatial distribution of nitrogen-cycling genes was more concentrated near the lakes and glaciers. Association rules revealed non-linear correlations between complex combinations of environmental variables and nitrogen-cycling genes. Association rules for the presence of denitrification genes presented a distinct combination of environmental variables from the remaining nitrogen-cycling genes. This study contributes to an integrative picture of the nitrogen-cycling potential in MDV.
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Mt. Erebus, Antarctica, is the world's southernmost active volcano and is unique in its isolation from other major active volcanic systems and its distinctive geothermal systems. Using 16S rRNA gene amplicon sequencing and physicochemical analyses, we compared samples collected at two contrasting high-temperature (50°C-65°C) sites on Mt. Erebus: Tramway Ridge, a weather-protected high biomass site, and Western Crater, an extremely exposed low biomass site. Samples were collected along three thermal gradients, one from Western Crater and two within Tramway Ridge, which allowed an examination of the heterogeneity present at Tramway Ridge. We found distinct soil compositions between the two sites, and to a lesser extent within Tramway Ridge, correlated with disparate microbial communities. Notably, pH, not temperature, showed the strongest correlation with these differences. The abundance profiles of several microbial groups were different between the two sites; class Nitrososphaeria amplicon sequence variants (ASVs) dominated the community profiles at Tramway Ridge, whereas Acidobacteriotal ASVs were only found at Western Crater. A co-occurrence network, paired with physicochemical analyses, allowed for finer scale analysis of parameters correlated with differential abundance profiles, with various parameters (total carbon, total nitrogen, soil moisture, soil conductivity, sulfur, phosphorous, and iron) showing significant correlations. ASVs assigned to Chloroflexi classes Ktedonobacteria and Chloroflexia were detected at both sites. Based on the known metabolic capabilities of previously studied members of these groups, we predict that chemolithotrophy is a common strategy in this system. These analyses highlight the importance of conducting broader-scale metagenomics and cultivation efforts at Mt. Erebus to better understand this unique environment.
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The effects of negative pressure wound therapy (NPWT) on wound edge microvascular blood flow are not clear. The aim of the present study was therefore to further elucidate the effects of NPWT on periwound blood flow in a porcine peripheral wound model using different blood flow measurement techniques. NPWT at -20, -40, -80, and -125 mmHg was applied to a peripheral porcine wound (n = 8). Thermodiffusion, transcutaneous, and invasive laser Doppler velocimetry were used to measure the blood perfusion 0.5, 1.0, and 2.5 cm from the wound edge. Thermodiffusion (an invasive measurement technique) generally showed a decrease in perfusion close to the wound edge (0.5 cm), and an increase further from the edge (2.5 cm). Invasive laser Doppler velocimetry showed a similar response pattern, with a decrease in blood flow 0.5 cm from the wound edge and an increase further away. However, 1.0 cm from the wound edge blood flow decreased with high pressure levels and increased with low pressure levels. A different response pattern was seen with transcutaneous laser Doppler velocimetry, showing an increase in blood flow regardless of the distance from the wound edge (0.5, 1.0, and 2.5 cm). During NPWT, both increases and decreases in blood flow can be seen in the periwound tissue depending on the distance from the wound edge and the pressure level. The pattern of response depends partly on the measurement technique used. The combination of hypoperfusion and hyperperfusion caused by NPWT may accelerate wound healing.
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Fluxometria por Laser-Doppler , Microcirculação , Tratamento de Ferimentos com Pressão Negativa , Difusão Térmica , Cicatrização/fisiologia , Animais , Músculo Esquelético/irrigação sanguínea , Músculo Esquelético/lesões , Pele/irrigação sanguínea , Pele/lesões , Sus scrofaRESUMO
Ecosystem feedbacks in response to ocean acidification can amplify or diminish diel pH oscillations in productive coastal waters. Benthic microalgae generate such oscillations in sediment porewater and here we ask how CO2 enrichment (acidification) of the overlying seawater alters these in the absence and presence of biogenic calcite. We placed a 1-mm layer of ground oyster shells, mimicking the arrival of dead calcifying biota (+Calcite), or sand (Control) onto intact silt sediment cores, and then gradually increased the pCO2 in the seawater above half of +Calcite and Control cores from 472 to 1216 µatm (pH 8.0 to 7.6, CO2:HCO3- from 4.8 to 9.6 × 10-4). Porewater [O2] and [H+] microprofiles measured 16 d later showed that this enrichment had decreased the O2 penetration depth (O2-pd) in +Calcite and Control, indicating a metabolic response. In CO2-enriched seawater: (1) sediment biogeochemical processes respectively added and removed more H+ to and from the sediment porewater in darkness and light, than in ambient seawater increasing the amplitude of the diel porewater [H+] oscillations, and (2) in darkness, calcite dissolution in +Calcite sediment decreased the porewater [H+] below that in overlying seawater, reversing the sediment-seawater H+ flux and decreasing the amplitude of diel [H+] oscillations. This dissolution did not, however, counter the negative effect of CO2 enrichment on O2-pd. We now hypothesise that feedback to CO2 enrichment-an increase in the microbial reoxidation of reduced solutes with O2-decreased the sediment O2-pd and contributed to the enhanced porewater acidification.
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CASE: A 37-year-old man presented with an absent right elbow joint secondary to trauma, subsequent ankylosis, total elbow arthroplasty (TEA), and TEA explantation after infection. The patient also had a contralateral complete brachial plexus injury, but an intact elbow joint. Given that the patient had a functional right hand/wrist, composite vascularized autograft elbow transplant was performed from left to right upper extremity. Four years postoperatively, the patient could independently complete activities of daily living. CONCLUSION: This case is the first to report composite vascularized autograft elbow transplant. Although indications are limited, this case illuminates novel uses of standard techniques for a difficult problem.
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Lesões no Cotovelo , Articulação do Cotovelo , Atividades Cotidianas , Adulto , Autoenxertos , Cotovelo/cirurgia , Articulação do Cotovelo/cirurgia , Humanos , Masculino , Articulação do PunhoRESUMO
Small bowel obstruction (SBO), of both partial and complete types, is a condition predominantly caused by intra-abdominal adhesions and hernias. However, a known but very uncommon cause of SBO is malignancies, which are more complicated than those caused by adhesions and hernias, and associated with poorer prognoses; of these, small bowel adenocarcinoma is an even rarer etiology of SBO. The majority of SBO cases that are treated have resolution of symptoms and do not have recurrence/persistence of the condition; however, reports suggest that approximately one-fifth of SBO cases that are treated will result in recurrence/persistence of SBO requiring repeat admission. Here we report the case of an 89-year-old female with a past medical history of right lower extremity deep venous thrombosis, inferior vena cava filter placement, iron deficiency anemia, diverticular disease, internal hemorrhoids, sick sinus syndrome, emphysema, hypertension, dyslipidemia, and hypothyroidism, who presented with diarrhea and intermittent dark stool. Abdominal computed tomography (CT) while in the emergency department initially showed possible ischemic bowel and SBO. After an exploratory laparotomy with small bowel resection and adhesiolysis, pathological analysis of a resected specimen showed infiltrating small bowel adenocarcinoma. Persistence of symptoms necessitated subsequent abdominal imaging, which demonstrated persistent SBO, which was treated with a second exploratory laparotomy with small bowel resection and end ileostomy.
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The space-for-time substitution approach provides a valuable empirical assessment to infer temporal effects of disturbance from spatial gradients. Applied to predict the response of different ecosystems under current climate change scenarios, it remains poorly tested in microbial ecology studies, partly due to the trophic complexity of the ecosystems typically studied. The McMurdo Dry Valleys (MDV) of Antarctica represent a trophically simple polar desert projected to experience drastic changes in water availability under current climate change scenarios. We used this ideal model system to develop and validate a microbial space-for-time sampling approach, using the variation of geochemical profiles that follow alterations in water availability and reflect past changes in the system. Our framework measured soil electrical conductivity, pH, and water activity in situ to geochemically define 17 space-for-time transects from the shores of four dynamic and two static Dry Valley lakes. We identified microbial taxa that are consistently responsive to changes in wetness in the soils and reliably associated with long-term dry or wet edaphic conditions. Comparisons between transects defined at static (open-basin) and dynamic (closed-basin) lakes highlighted the capacity for geochemically defined space-for-time gradients to identify lasting deterministic impacts of historical changes in water presence on the structure and diversity of extant microbial communities. We highlight the potential for geochemically defined space-for-time transects to resolve legacy impacts of environmental change when used in conjunction with static and dynamic scenarios, and to inform future environmental scenarios through changes in the microbial community structure, composition, and diversity.