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While sexual dimorphism in immune responses has been documented in other vertebrates, evidence for a similar phenomenon in fish is lacking. Here, we review the relationship between immunity, stress, spawning, and sex hormones in fish to gain a better understanding of sex-based differences in fish immune responses and its consequences for aquaculture. It is well known that there is a strong link between the stress response and immune function in fish. In addition, research to date has demonstrated that sexual dimorphism in the stress response exists in many species; yet, the relationship between the sexual dimorphic stress responses and immune function has rarely been explored together. Aside from stress, spawning is also known to trigger changes in fish immune responses. Estrogens and androgens have been shown to modulate the immune system which could account for differences between the two sexes of fish when spawning; however, evidence regarding the sexual dimorphism of these changes varies between fishes and is likely related to the spawning strategy employed by a given species. Sex hormones are also used in aquaculture practices to produce monosex populations, and exposure to these hormones early in development has been shown to impact the development of immune organs in several fishes. While female fish are generally thought to be more robust than males, aquaculture practices should also consider the role that maternal stress has on the immune function of the offspring and what role this plays in compromising the immune response of farmed fish.
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Peixes/imunologia , Imunidade/imunologia , Reprodução/imunologia , Estresse Fisiológico/imunologia , Androgênios/imunologia , Animais , Aquicultura , Estrogênios/imunologia , Peixes/fisiologia , Caracteres SexuaisRESUMO
OBJECTIVE: The aim of this study was to establish the mobility, satisfaction, and quality of life (QoL) among prosthesis users with dysvascular/diabetic amputation at both acute and long-term phases of prosthetic rehabilitation. METHODS: This is a multisite, cross-sectional outcomes analysis. A total of 341 individuals met the inclusion/exclusion criteria. Individuals were grouped into acute phases (0-3 months [n = 24], 4-6 months [n = 72]) and chronic phases (24-36 months [n = 91], 37-48 months [n = 53], 49-60 months [n = 47], and 60-84 months [n = 54]) after amputation. Mobility was measured with the Prosthetic Limb Users Survey of Mobility (PLUS-M), whereas QoL and satisfaction (Sat) were reported using 10-point scales adapted from the Prosthesis Evaluation Questionnaire-Well-Being (PEQ-WB). Composite PEQ-WB scores were also compared. RESULTS: The average mobility, QoL, and Sat among prosthesis users was, respectively, 44.8 ± 10.6, 7.6 ± 2.2, and 7.6 ± 2.2. There were no observed differences in mobility (F 5,330 = 1.52, P = 0.18), QoL (F 5,333 = 0.78, P = 0.57), or PEQ-WB (F 5,335 = 1.618, P = 0.155) between any groups. For Sat, there was a group difference (F 5,334 = 2.44, P = 0.03) as individuals appear to experience an initial increase in Sat with receipt of a prosthesis (0-3 months) compared with 25 to 36 months (P = 0.005), 49 to 60 months (P = 0.008), and 61 to 84 months (P = 0.009). CONCLUSIONS: Those individuals with amputation secondary to dysvascular disease and diabetes who continue to participate in prosthetic rehabilitation appear to experience levels of mobility, Sat, and QoL 7 years after amputation comparable to that reported in the first 6 months postamputation. There may be a modest increase in Sat with receipt of an initial prosthesis, potentially due to an increased optimism for one's situation. Notably, the mobility levels observed in the dysvascular population through a range of long-term postamputation periods remain within a single standard deviation of the population mean for individuals with a lower-limb amputation using a prosthesis for mobility.
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The composition of the human microbiota is recognized as an important factor in human health and disease. Many of our cohabitating microbes belong to phylum-level divisions for which there are no cultivated representatives and are only represented by small subunit rRNA sequences. For one such taxon (SR1), which includes bacteria with elevated abundance in periodontitis, we provide a single-cell genome sequence from a healthy oral sample. SR1 bacteria use a unique genetic code. In-frame TGA (opal) codons are found in most genes (85%), often at loci normally encoding conserved glycine residues. UGA appears not to function as a stop codon and is in equilibrium with the canonical GGN glycine codons, displaying strain-specific variation across the human population. SR1 encodes a divergent tRNA(Gly)UCA with an opal-decoding anticodon. SR1 glycyl-tRNA synthetase acylates tRNA(Gly)UCA with glycine in vitro with similar activity compared with normal tRNA(Gly)UCC. Coexpression of SR1 glycyl-tRNA synthetase and tRNA(Gly)UCA in Escherichia coli yields significant ß-galactosidase activity in vivo from a lacZ gene containing an in-frame TGA codon. Comparative genomic analysis with Human Microbiome Project data revealed that the human body harbors a striking diversity of SR1 bacteria. This is a surprising finding because SR1 is most closely related to bacteria that live in anoxic and thermal environments. Some of these bacteria share common genetic and metabolic features with SR1, including UGA to glycine reassignment and an archaeal-type ribulose-1,5-bisphosphate carboxylase (RubisCO) involved in AMP recycling. UGA codon reassignment renders SR1 genes untranslatable by other bacteria, which impacts horizontal gene transfer within the human microbiota.
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Bactérias/genética , Códon de Terminação/genética , Código Genético/genética , Glicina/genética , Metagenoma/genética , Boca/microbiologia , Sequência de Bases , Citometria de Fluxo , Variação Genética , Humanos , Dados de Sequência Molecular , Técnicas de Amplificação de Ácido Nucleico , Análise de Sequência de DNARESUMO
Small heat shock proteins (sHSPs) are molecular chaperones that bind to unfolded protein, inhibit the formation of toxic aggregates and facilitate their refolding and/or degradation. Previously, the only sHSPs that have been studied in detail in the model frog system, Xenopus laevis, were members of the HSP30 family and HSPB1 (HSP27). We now report the analysis of X. laevis HSPB6, an ortholog of mammalian HSPB6. X. laevis HSPB6 cDNA encodes a 168 aa protein that contains an α-crystallin domain, a polar C-terminal extension and some possible phosphorylation sites. X. laevis HSPB6 shares 94% identity with a X. tropicalis HSPB6, 65% with turtle, 59% with humans, 49% with zebrafish and only 50% and 43% with X. laevis HSPB1 and HSP30C, respectively. Phylogenetic analysis revealed that X. laevis HSPB6 grouped more closely with mammalian and reptilian HSPB6s than with fish HSPB6. X. laevis recombinant HSPB6 displayed molecular chaperone properties since it had the ability to inhibit heat-induced aggregation of citrate synthase. Immunoblot analysis determined that HSPB6 was present constitutively in kidney epithelial cells and that heat shock treatment did not upregulate HSPB6 levels. While treatment with the proteasomal inhibitor, MG132, resulted in a 2-fold increase in HSPB6 levels, exposure to cadmium chloride produced a slight increase in HSPB6. These findings were in contrast to HSP70, which was enhanced in response to all three stressors. Finally, immunocytochemical analysis revealed that HSPB6 was present in the cytoplasm in the perinuclear region with some in the nucleus.
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Proteínas de Choque Térmico HSP20/genética , Proteínas de Choque Térmico HSP20/metabolismo , Proteínas de Xenopus/genética , Proteínas de Xenopus/metabolismo , Xenopus laevis/genética , Xenopus laevis/metabolismo , Sequência de Aminoácidos , Animais , Sequência de Bases , Linhagem Celular , DNA Complementar/genética , Células Epiteliais/metabolismo , Expressão Gênica , Proteínas de Choque Térmico HSP20/química , Imuno-Histoquímica , Rim/metabolismo , Filogenia , Domínios Proteicos , Homologia de Sequência de Aminoácidos , Proteínas de Xenopus/químicaRESUMO
BACKGROUND: The Arabidopsis thaliana protein atTic20 is a key component of the protein import machinery at the inner envelope membrane of chloroplasts. As a component of the TIC complex, it is believed to form a preprotein-conducting channel across the inner membrane. RESULTS: We report a method for producing large amounts of recombinant atTic20 using a codon-optimized strain of E. coli coupled with an autoinduction method of protein expression. This method resulted in the recombinant protein being directed to the bacterial membrane without the addition of a bacterial targeting sequence. Using biochemical and biophysical approaches, we were able to demonstrate that atTic20 homo-oligomerizes in vitro when solubilized in detergents or reconstituted into liposomes. Furthermore, we present evidence that the extramembranous N-terminus of the mature protein displays characteristics that are consistent with it being an intrinsically disordered protein domain. CONCLUSION: Our work strengthens the hypothesis that atTic20 functions similarly to other small α-helical integral membrane proteins, such as Tim23, that are involved in protein transport across membranes.
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Proteínas de Arabidopsis/química , Arabidopsis/metabolismo , Cloroplastos/metabolismo , Membranas Intracelulares/metabolismo , Proteínas de Membrana Transportadoras/química , Sequência de Aminoácidos , Proteínas de Arabidopsis/biossíntese , Escherichia coli , Proteínas Intrinsicamente Desordenadas/biossíntese , Proteínas Intrinsicamente Desordenadas/química , Lipossomos , Proteínas de Membrana Transportadoras/biossíntese , Dados de Sequência Molecular , Fosfatidilcolinas/química , Dobramento de Proteína , Multimerização Proteica , Redobramento de Proteína , Estrutura Terciária de Proteína , Transporte ProteicoRESUMO
Introduction: Many military service members and civilians suffer from lower extremity trauma. Despite recent advancements in lower limb bracing technology, it remains unclear whether these newer advanced braces offer improved comfort and functionality compared to conventional options. The IDEO (Intrepid Dynamic Exoskeletal Orthosis), a type of "advanced" orthosis was developed to assist in maintaining high functional performance in patients who have experienced high-energy lower extremity trauma and underwent limb salvage surgeries. Methods: A cross-sector multi-site initiative was completed to study the efficacy of advanced ankle foot orthoses (AFO) for lower limb trauma and injury compared to a conventional AFO. Following fitting, training, and accommodation, the subjects were assessed in each AFO system for mobility, self-reported function, safety and pain, and preference. Results: They preferred the advanced over the conventional AFO and the mobility and exertion perception improved with the advanced AFO with no difference in pain or overall health status scores. Discussion: Thus, an advanced AFO is an option for trauma affecting the lower limb. Long-term studies are required to better understand the accommodation and learning process of using an advanced AFO.
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Next-generation sequencing has dramatically changed the landscape of microbial ecology, large-scale and in-depth diversity studies being now widely accessible. However, determining the accuracy of taxonomic and quantitative inferences and comparing results obtained with different approaches are complicated by incongruence of experimental and computational data types and also by lack of knowledge of the true ecological diversity. Here we used highly diverse bacterial and archaeal synthetic communities assembled from pure genomic DNAs to compare inferences from metagenomic and SSU rRNA amplicon sequencing. Both Illumina and 454 metagenomic data outperformed amplicon sequencing in quantifying the community composition, but the outcome was dependent on analysis parameters and platform. New approaches in processing and classifying amplicons can reconstruct the taxonomic composition of the community with high reproducibility within primer sets, but all tested primers sets lead to significant taxon-specific biases. Controlled synthetic communities assembled to broadly mimic the phylogenetic richness in target environments can provide important validation for fine-tuning experimental and computational parameters used to characterize natural communities.
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Archaea/classificação , Archaea/genética , Bactérias/classificação , Bactérias/genética , Biodiversidade , Metagenômica , Técnicas Microbiológicas/normas , Primers do DNA/genética , Sequenciamento de Nucleotídeos em Larga Escala , Filogenia , RNA Ribossômico/genética , Reprodutibilidade dos TestesRESUMO
Individuals with lower limb amputation have a high incidence of falls. Above-the-knee amputation and diabetes/vascular disease are both risk factors for falls. Microprocessor knee (MPK) technology may reduce falls in this population. The objective was to determine the association between MPKs and reduced injurious falls. A retrospective analysis of injurious falls within a large, national outcomes database was conducted. Inclusion was limited to adult K3 ambulators with unilateral, transfemoral, or knee disarticulation amputation due to diabetes/vascular disease. There were 744 out of 881 individuals that did not receive an MPK. Results showed that 16.3% of non-MPK users experienced an injurious fall compared to 7.3% of MPK users (p = .007). Not having an MPK resulted in significantly increased odds (unadjusted: OR: 2.47, 95% CI: 1.26-4.83, p = .009; adjusted for confounders: OR: 2.52, 95% CI: 1.28-4.94, p = .007) of incurring an injurious fall over a 6-month period. In conclusion, the current study found use of an MPK strongly associated with reduced injurious falls in a population of patients with amputation due to diabetes/vascular disease. The findings strongly support the use of MPK technology to mitigate fall risk, and in particular injurious falls requiring medical intervention.
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Amputados , Membros Artificiais , Diabetes Mellitus , Doenças Vasculares , Adulto , Humanos , Estudos Retrospectivos , Acidentes por Quedas/prevenção & controle , Amputação Cirúrgica , Extremidade Inferior , MicrocomputadoresRESUMO
PURPOSE: As United States healthcare transitions from traditional fee-for-service models to value-based care, there is increased need to demonstrate quality care through clinical outcomes. Therefore, the purpose of this study was to create equations to calculate an expected mobility score for lower limb prosthesis users specific to their age, etiology, and amputation level to provide benchmarks to qualify good outcomes. MATERIALS AND METHODS: A retrospective cross-sectional analysis of outcomes collected during clinical care was performed. Individuals were grouped based on amputation level (unilateral above-knee (AKA) or below-knee (BKA)) and etiology (trauma or diabetes/dysvascular (DV)). The mean mobility score (PLUS-M® T-score) for each year of age was calculated. AKAs were further stratified into having a microprocessor knee (MPK) or non-microprocessor (nMPK) for secondary analysis. RESULTS: As expected, average prosthetic mobility declined with age. Overall, BKAs had higher PLUS-M T-scores compared to AKAs and trauma etiologies had higher scores compared to DV. For AKAs, those with a MPK had higher T-scores compared to those with a nMPK. CONCLUSIONS: Results from this study provide average mobility for adult patients across every year of life. This can be leveraged to create a mobility adjustment factor to qualify good outcomes in lower limb prosthetic care.IMPLICATIONS FOR REHABILITATIONNormative values of mobility are needed to qualify good outcomes in prosthetic care as healthcare shifts towards value-based care.Understanding where an individual is relative to others with similar characteristics (e.g., age, etiology, gender, amputation level, and device type) can provide clinicians with better benchmarks for individual goal-setting.The ability to generate predicted mobility scores specific to each individual can create a mobility adjustment factor to better qualify good outcomes.
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BACKGROUND: For individuals with a disability, an increase in functional mobility may improve their quality of life and well-being. Greater understanding is needed on how factors such as gender, geography, and employment may play a role in mobility levels among individuals with lower limb amputation. OBJECTIVES: To assess the relationship between gender, geography, and employment status on mobility among lower limb prosthesis users. METHODS: A cross-sectional analysis of 7,524 patient mobility outcomes completed across the United States was performed. The regression model included the independent variables, such as age, gender, region, employment status, and amputation level. Mobility was entered as the dependent variable. RESULTS: Individuals who were employed had 3.6 times the odds of reaching increased mobility (Prosthetic Limb Users' Survey of Mobility ≥ 50) than those unemployed (odds ratio 3.56, 95% confidence interval 3.10-4.09). Gender and geography were significantly associated with mobility as well. CONCLUSIONS: Being employed is associated with greater odds of reaching increased mobility. Addressing factors such as returning to employment may aid in improving mobility levels among prosthesis users.
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Amputados , Membros Artificiais , Humanos , Estados Unidos , Qualidade de Vida , Estudos Transversais , Extremidade Inferior , GeografiaRESUMO
The determination of the success of in situ bioremediation strategies is complex. By using controlled laboratory conditions, the influence of individual variables, such as U(VI), Cr(VI), and electron donors and acceptors on community structure, dynamics, and the metal-reducing potential can be studied. Triplicate anaerobic, continuous-flow reactors were inoculated with Cr(VI)-contaminated groundwater from the Hanford, WA, 100-H area, amended with lactate, and incubated for 95 days to obtain stable, enriched communities. The reactors were kept anaerobic with N(2) gas (9 ml/min) flushing the headspace and were fed a defined medium amended with 30 mM lactate and 0.05 mM sulfate with a 48-h generation time. The resultant diversity decreased from 63 genera within 12 phyla to 11 bacterial genera (from 3 phyla) and 2 archaeal genera (from 1 phylum). Final communities were dominated by Pelosinus spp. and to a lesser degree, Acetobacterium spp., with low levels of other organisms, including methanogens. Four new strains of Pelosinus were isolated, with 3 strains being capable of Cr(VI) reduction while one also reduced U(VI). Under limited sulfate, it appeared that the sulfate reducers, including Desulfovibrio spp., were outcompeted. These results suggest that during times of electron acceptor limitation in situ, organisms such as Pelosinus spp. may outcompete the more-well-studied organisms while maintaining overall metal reduction rates and extents. Finally, lab-scale simulations can test new strategies on a smaller scale while facilitating community member isolation, so that a deeper understanding of community metabolism can be revealed.
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Biodegradação Ambiental , Ecossistema , Sedimentos Geológicos/microbiologia , Lactatos/metabolismo , Urânio/metabolismo , Veillonellaceae/crescimento & desenvolvimento , Archaea/classificação , Archaea/genética , Archaea/crescimento & desenvolvimento , Archaea/isolamento & purificação , Archaea/metabolismo , Bactérias/classificação , Bactérias/genética , Bactérias/crescimento & desenvolvimento , Bactérias/isolamento & purificação , Bactérias/metabolismo , Reatores Biológicos , Cromo/metabolismo , Meios de Cultura , DNA Arqueal/análise , DNA Arqueal/genética , DNA Bacteriano/análise , DNA Bacteriano/genética , Água Subterrânea/microbiologia , Dados de Sequência Molecular , Oxirredução , Filogenia , RNA Ribossômico 16S , Análise de Sequência de DNA , Veillonellaceae/classificação , Veillonellaceae/genética , Veillonellaceae/isolamento & purificaçãoRESUMO
OBJECTIVE: To examine variations in timing of lower-limb amputation (LLA) across race/ethnicity and sex among older adults with a diabetic foot ulcer (DFU). It was hypothesized Black/African Americans were more likely to have LLA post-DFU earlier compared with non-Hispanic/Whites, and more men would receive LLA earlier post-DFU compared with women. RESEARCH DESIGN AND METHODS: This was a retrospective cohort analysis of enrolled Medicare fee-for-service (FFS) beneficiaries with a diagnosis of DFU during the study period (2012-2017), allowing up to 5 years post-DFU. Final analytic sample contained 643,287 individuals; the subsample consisted of 68,633 individuals with LLA only. The primary outcome was mutually exclusive groups based on timing of LLA. Multinomial logistic regression was applied to assess likelihood of membership into a group post-DFU based on characteristics such as sex and race/ethnicity. RESULTS: Black/African American beneficiaries had 1.98 (95% CI 1.93-2.03) times the odds of receiving an LLA within 1 year of DFU diagnosis compared with non-Hispanic/White beneficiaries relative to no amputation. Female beneficiaries had increased odds (odds ratio [OR] 1.07, 95% CI 1.02-1.11] between 1 and 3 years and OR 1.08 [95% CI 1.03-1.12] in ≥3 years) of a delayed LLA compared with men among those that underwent LLA. CONCLUSIONS: Notably, these results present novel evidence on timing of LLA between racial groups and sex for Medicare FFS beneficiaries post-DFU. Results may be generalizable to individuals with Medicare FFS and DFU. Clinically more targeted, evidence-based decision making informs care decisions with opportunities to address inequities related to the social determinants of health that may lead to LLA.
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Diabetes Mellitus , Pé Diabético , Idoso , Amputação Cirúrgica , Pé Diabético/cirurgia , Feminino , Disparidades em Assistência à Saúde , Humanos , Masculino , Medicare , Estudos Retrospectivos , Estados UnidosRESUMO
OBJECTIVE: The aim of the study was to establish normative values of lower limb amputation mobility across primary etiologies based on age and amputation level. DESIGN: This study is a cross-sectional observational analysis of outcomes. A total of 11,995 lower limb prosthesis users were included in the analysis. Participants were grouped by etiology into four categories: cancer, congenital, trauma, and diabetes/dysvascular. Mobility was assessed by using the Prosthetic Limb Users Survey of Mobility. RESULTS: Mobility across seven age groups for the four etiologies was established for both above-the-knee amputation and below-the-knee amputation. Differences were found between age groups for individuals: above-the-knee amputation: cancer (χ 2 (6) = 40.97, P < 0.001), congenital (χ 2 (3) = 9.41, P = 0.024), trauma (χ 2 (6) = 18.89, P = 0.004), and dysvascular (χ 2 (5) = 39.73, P < 0.001; below-the-knee amputation: cancer (χ 2 (6) = 29.77, P < 0.001), trauma (χ 2 (6) = 28.22, P < 0.001), and dysvascular (χ 2 (6) = 144.66, P < 0.001). CONCLUSIONS: The awareness of differences across amputation etiologies extending across the lifespan of ages can assist the goal-setting process as part of prosthetic rehabilitation. In addition, refined normative values provide the ability to benchmark new and innovative changes in clinical practice.
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Amputados , Membros Artificiais , Amputação Cirúrgica/reabilitação , Amputados/reabilitação , Estudos Transversais , Humanos , Extremidade Inferior/cirurgia , Inquéritos e QuestionáriosRESUMO
Introduction: Recently, many prosthetic devices were subjected to reimbursement coding review. Several prosthetic feet that were historically coded with the shock-attenuating function were recoded. The purpose of this analysis was to compare patient-reported functional mobility across a range of prosthetic feet using real-world clinical outcomes data. Methods: A retrospective, observational review. A univariate generalized linear model was used to assess mobility across foot categories and between different prosthetic feet coded as L5987 or L5981. Results: The final sample analyzed comprised of 526 individuals and four mutually exclusive categories of feet examined across a total of 10 different prosthetic foot types. The comparison of prosthetic foot categories were significantly different from the control category (i.e. historically L5981). Conclusions: The current data suggest the development of some prosthetic foot designs using advanced materials and geometric designs can provide comparable functional benefits as those with distinct shock absorbing mechanical features. Emphasizing functional performance over visible features may be a pathway towards higher performance for the end user.
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Subsurface microbial community distribution patterns are influenced by biogeochemical and groundwater fluxes and may inform hydraulic connections along groundwater-flow paths. This study examined the regional-scale microbial community of the Death Valley Regional Flow System and evaluated whether subsurface communities can be used to identify groundwater-flow paths between recharge and discharge areas. Samples were collected from 36 sites in three groundwater basins: Pahute Mesa-Oasis Valley (PMOV), Ash Meadows (AM), and Alkali Flat-Furnace Creek Ranch (AFFCR). Microbial diversity within and between communities varied by location, and communities were separated into two overall groups that affiliated with the AM and PMOV/AFFCR basins. Network analysis revealed patterns between clusters of common microbes that represented groundwaters with similar geochemical conditions and largely corroborated hydraulic connections between recharge and discharge areas. Null model analyses identified deterministic and stochastic ecological processes contributing to microbial community assemblages. Most communities were more different than expected and governed by dispersal limitation, geochemical differences, or undominating processes. However, certain communities from sites located within or near the Nevada National Security Site were more similar than expected and dominated by homogeneous dispersal or selection. Overall, the (dis)similarities between the microbial communities of DVRFS recharge and discharge areas supported previously documented hydraulic connections between: (1) Spring Mountains and Ash Meadows; (2) Frenchman and Yucca Flat and Amargosa Desert; and (3) Amargosa Desert and Death Valley. However, only a portion of the flow path between Pahute Mesa and Oasis Valley could be supported by microbial community analyses, likely due to well-associated artifacts in samples from the two Oasis Valley sites. This study demonstrates the utility of combining microbial data with hydrologic, geologic, and water-chemistry information to comprehensively characterize groundwater systems, highlighting both strengths and limitations of this approach.
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Água Subterrânea , Microbiota , Geologia , Água Subterrânea/química , Hidrologia , NevadaRESUMO
To evaluate the effects of local fluid geochemistry on microbial communities associated with active hydrothermal vent deposits, we examined the archaeal and bacterial communities of 12 samples collected from two very different vent fields: the basalt-hosted Lucky Strike (37°17'N, 32°16.3'W, depth 1600-1750 m) and the ultramafic-hosted Rainbow (36°13'N, 33°54.1'W, depth 2270-2330 m) vent fields along the Mid-Atlantic Ridge (MAR). Using multiplexed barcoded pyrosequencing of the variable region 4 (V4) of the 16S rRNA genes, we show statistically significant differences between the archaeal and bacterial communities associated with the different vent fields. Quantitative polymerase chain reaction (qPCR) assays of the functional gene diagnostic for methanogenesis (mcrA), as well as geochemical modelling to predict pore fluid chemistries within the deposits, support the pyrosequencing observations. Collectively, these results show that the less reduced, hydrogen-poor fluids at Lucky Strike limit colonization by strict anaerobes such as methanogens, and allow for hyperthermophilic microaerophiles, like Aeropyrum. In contrast, the hydrogen-rich reducing vent fluids at the ultramafic-influenced Rainbow vent field support the prevalence of methanogens and other hydrogen-oxidizing thermophiles at this site. These results demonstrate that biogeographical patterns of hydrothermal vent microorganisms are shaped in part by large scale geological and geochemical processes.
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Archaea/classificação , Bactérias/classificação , Biodiversidade , Fontes Hidrotermais/microbiologia , Archaea/genética , Bactérias/genética , Sedimentos Geológicos/química , Sedimentos Geológicos/microbiologia , Geologia , Fontes Hidrotermais/química , Dados de Sequência Molecular , Filogenia , Reação em Cadeia da Polimerase , RNA Ribossômico 16S/genética , Água do Mar/química , Água do Mar/microbiologiaRESUMO
Subsurface amendments of slow-release substrates (e.g., emulsified vegetable oil [EVO]) are thought to be a pragmatic alternative to using short-lived, labile substrates for sustained uranium bioimmobilization within contaminated groundwater systems. Spatial and temporal dynamics of subsurface microbial communities during EVO amendment are unknown and likely differ significantly from those of populations stimulated by soluble substrates, such as ethanol and acetate. In this study, a one-time EVO injection resulted in decreased groundwater U concentrations that remained below initial levels for approximately 4 months. Pyrosequencing and quantitative PCR of 16S rRNA from monitoring well samples revealed a rapid decline in groundwater bacterial community richness and diversity after EVO injection, concurrent with increased 16S rRNA copy levels, indicating the selection of a narrow group of taxa rather than a broad community stimulation. Members of the Firmicutes family Veillonellaceae dominated after injection and most likely catalyzed the initial oil decomposition. Sulfate-reducing bacteria from the genus Desulforegula, known for long-chain fatty acid oxidation to acetate, also dominated after EVO amendment. Acetate and H(2) production during EVO degradation appeared to stimulate NO(3)(-), Fe(III), U(VI), and SO(4)(2-) reduction by members of the Comamonadaceae, Geobacteriaceae, and Desulfobacterales. Methanogenic archaea flourished late to comprise over 25% of the total microbial community. Bacterial diversity rebounded after 9 months, although community compositions remained distinct from the preamendment conditions. These results demonstrated that a one-time EVO amendment served as an effective electron donor source for in situ U(VI) bioreduction and that subsurface EVO degradation and metal reduction were likely mediated by successive identifiable guilds of organisms.
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Archaea/classificação , Archaea/metabolismo , Bactérias/classificação , Bactérias/metabolismo , Poluentes Ambientais/metabolismo , Consórcios Microbianos , Urânio/metabolismo , Archaea/isolamento & purificação , Bactérias/isolamento & purificação , Análise por Conglomerados , DNA Arqueal/química , DNA Arqueal/genética , DNA Bacteriano/química , DNA Bacteriano/genética , DNA Ribossômico/química , DNA Ribossômico/genética , Genes de RNAr , RNA Arqueal/genética , RNA Bacteriano/genética , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Homologia de Sequência do Ácido Nucleico , Microbiologia do SoloRESUMO
OBJECTIVE: The aim of the study was to assess the validity of a customized nine-item Patient-Reported Outcomes Measurement Information System Upper Extremity instrument being used with individuals with upper extremity amputation to inform potential modifications for clinical efficiency. DESIGN: A sample of 239 adults with upper extremity amputation (mean age = 48 ± 16 yrs; female = 69; prosthesis users = 150) were included. After clinical implementation of the nine-item Patient-Reported Outcomes Measurement Information System Upper Extremity, the following psychometric properties were examined: structural and known-groups validity, differential item functioning, and reliability. RESULTS: The nine-item Patient-Reported Outcomes Measurement Information System Upper Extremity short form demonstrated satisfactory psychometric properties. Convincing evidence of structural validity included no violation of unidimensionality, local independence (all local dependence χ2 < 10), monotonicity (Hij > 0, Hi > 0.3, and H = 0.57), and adequate model fit (P > 0.006). Known-groups analysis demonstrated that the nine-item Patient-Reported Outcomes Measurement Information System Upper Extremity instrument was able to discriminate between prosthesis users and nonprosthesis users and amputation level. The Cronbach's α and item response theory reliability at the selected range of T scores were greater than 0.9 indicating high reliability. No items were flagged for age in differential item functioning. CONCLUSIONS: The customized nine-item Patient-Reported Outcomes Measurement Information System Upper Extremity met the minimum criteria, according to the Patient-Reported Outcomes Measurement Information System plan, for psychometric validity supporting its use within the population of individuals with upper extremity amputation.
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Amputação Cirúrgica , Medidas de Resultados Relatados pelo Paciente , Extremidade Superior/cirurgia , Membros Artificiais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , PsicometriaRESUMO
Cell-1 is a host-derived beta-1,4-endoglucanase (Glycohydrolase Family 9 [GHF9]) from the lower termite Reticulitermes flavipes. Here, we report on the heterologous production of Cell-1 using eukaryotic (Baculovirus Expression Vector System; BEVS) and prokaryotic (E. coli) expression systems. The BEVS-expressed enzyme was more readily obtained in solubilized form and more active than the E. coli-expressed enzyme. K(m) and V(max) values for BEVS-expressed Cell-1 against the model substrate CMC were 0.993% w/v and 1.056 micromol/min/mg. Additional characterization studies on the BEVS-expressed enzyme revealed that it possesses activity comparable to the native enzyme, is optimally active around pH 6.5-7.5 and 50-60 degrees C, is inhibited by EDTA, and displays enhanced activity up to 70 degrees C in the presence of CaCl(2). These findings provide a foundation on which to begin subsequent investigations of collaborative digestion by coevolved host and symbiont digestive enzymes from R. flavipes that include GHF7 exoglucanases, GHF1 beta glucosidases, phenol-oxidizing laccases, and others.
Assuntos
Celulase/biossíntese , Isópteros/metabolismo , Animais , Sequência de Bases , Western Blotting , Celulase/metabolismo , Colorimetria , Primers do DNA , Eletroforese em Gel de Poliacrilamida , Concentração de Íons de Hidrogênio , Fases de Leitura Aberta , Proteínas Recombinantes/metabolismo , TemperaturaRESUMO
The objective of this cross-sectional observational study was to determine whether the use of a microprocessor knee for individuals with an above-the-knee amputation results in improved functional mobility compared to their peers of matched comorbid-health with a non-microprocessor knee, and to inform how this compares to the mobility observed in below-knee prosthesis users. A sample of 450 individuals with lower limb amputation were divided into three groups (n = 150 each). The groups included: nonmicroprocessor knee users (NMPK, age: 57.6 ± 17.2 years), microprocessor knee users (MPK, age: 56.5 ± 13.8 years), and below-knee prosthesis users (BKA, age: 58.4 ± 12.2 years). Primary outcome measure was functional mobility measured through Prosthetic Limb Users' Survey of Mobility (PLUS-M®). Results showed MPK mobility (48.49 ± 0.86) was greater than NMPK (43.49 ± 0.86, p < 0.001), but less than BKA (52.11 ± 0.86, p = 0.003). These results persisted when removing potential confounding effects of age, body mass index, cause of amputation, and comorbid health (MPK: 47.15 ± 0.97; NMPK: 43.47 ± 0.88; BKA: 52.61 ± 0.91). In conclusion, these results show the use of a MPK can improve functional mobility for individuals with an above-knee amputation.