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1.
Proc Biol Sci ; 289(1974): 20212702, 2022 05 11.
Artículo en Inglés | MEDLINE | ID: mdl-35538775

RESUMEN

Amidst global shifts in the distribution and abundance of wildlife and livestock, we have only a rudimentary understanding of ungulate parasite communities and parasite-sharing patterns. We used qPCR and DNA metabarcoding of fecal samples to characterize gastrointestinal nematode (Strongylida) community composition and sharing among 17 sympatric species of wild and domestic large mammalian herbivore in central Kenya. We tested a suite of hypothesis-driven predictions about the role of host traits and phylogenetic relatedness in describing parasite infections. Host species identity explained 27-53% of individual variation in parasite prevalence, richness, community composition and phylogenetic diversity. Host and parasite phylogenies were congruent, host gut morphology predicted parasite community composition and prevalence, and hosts with low evolutionary distinctiveness were centrally positioned in the parasite-sharing network. We found no evidence that host body size, social-group size or feeding height were correlated with parasite composition. Our results highlight the interwoven evolutionary and ecological histories of large herbivores and their gastrointestinal nematodes and suggest that host identity, phylogeny and gut architecture-a phylogenetically conserved trait related to parasite habitat-are the overriding influences on parasite communities. These findings have implications for wildlife management and conservation as wild herbivores are increasingly replaced by livestock.


Asunto(s)
Nematodos , Parásitos , Animales , Animales Salvajes/parasitología , Herbivoria , Interacciones Huésped-Parásitos , Ganado , Mamíferos , Filogenia
2.
Ecol Lett ; 24(9): 1880-1891, 2021 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-34212477

RESUMEN

Explaining large-scale ordered patterns and their effects on ecosystem functioning is a fundamental and controversial challenge in ecology. Here, we coupled empirical and theoretical approaches to explore how competition and spatial heterogeneity govern the regularity of colony dispersion in fungus-farming termites. Individuals from different colonies fought fiercely, and inter-nest distances were greater when nests were large and resources scarce-as expected if competition is strong, large colonies require more resources and foraging area scales with resource availability. Building these principles into a model of inter-colony competition showed that highly ordered patterns emerged under high resource availability and low resource heterogeneity. Analysis of this dynamical model provided novel insights into the mechanisms that modulate pattern regularity and the emergent effects of these patterns on system-wide productivity. Our results show how environmental context shapes pattern formation by social-insect ecosystem engineers, which offers one explanation for the marked variability observed across ecosystems.


Asunto(s)
Ecosistema , Isópteros , Agricultura , Animales , Ecología , Humanos , Insectos
3.
Mol Ecol ; 29(22): 4487-4501, 2020 11.
Artículo en Inglés | MEDLINE | ID: mdl-32761930

RESUMEN

Spatially overdispersed mounds of fungus-farming termites (Macrotermitinae) are hotspots of nutrient availability and primary productivity in tropical savannas, creating spatial heterogeneity in communities and ecosystem functions. These termites influence the local availability of nutrients in part by redistributing nutrients across the landscape, but the links between termite ecosystem engineering and the soil microbes that are the metabolic agents of nutrient cycling are little understood. We used DNA metabarcoding of soils from Odontotermes montanus mounds to examine the influence of termites on soil microbial communities in a semi-arid Kenyan savanna. We found that bacterial and fungal communities were compositionally distinct in termite-mound topsoils relative to the surrounding savanna, and that bacterial communities were more diverse on mounds. The higher microbial alpha and beta diversity associated with mounds created striking spatial patterning in microbial community composition, and boosted landscape-scale microbial richness and diversity. Selected enzyme assays revealed consistent differences in potential enzymatic activity, suggesting links between termite-induced heterogeneity in microbial community composition and the spatial distribution of ecosystem functions. We conducted a large-scale field experiment in which we attempted to simulate termites' effects on microbes by fertilizing mound-sized patches; this altered both bacterial and fungal communities, but in a different way than natural mounds. Elevated levels of inorganic nitrogen, phosphorus and potassium may help to explain the distinctive fungal communities in termite-mound soils, but cannot account for the distinctive bacterial communities associated with mounds.


Asunto(s)
Isópteros , Microbiota , Agricultura , Animales , Hongos/genética , Isópteros/genética , Kenia , Microbiota/genética , Suelo
4.
Proc Biol Sci ; 284(1850)2017 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-28298347

RESUMEN

Three ant species nest obligately in the swollen-thorn domatia of the African ant-plant Vachellia (Acacia) drepanolobium, a model system for the study of ant-defence mutualisms and species coexistence. Here we report on the characteristic fungal communities generated by these ant species in their domatia. First, we describe behavioural differences between the ant species when presented with a cultured fungal isolate in the laboratory. Second, we use DNA metabarcoding to show that each ant species has a distinctive fungal community in its domatia, and that these communities remain characteristic of the ant species over two Kenyan sampling locations separated by 190 km. Third, we find that DNA extracted from female alates of Tetraponera penzigi and Crematogaster nigriceps contained matches for most of the fungal metabarcodes from those ant species' domatia, respectively. Fungal hyphae and other debris are also visible in sections of these alates' infrabuccal pockets. Collectively, our results indicate that domatium fungal communities are associated with the ant species occupying the tree. To the best of our knowledge, this is the first record of such ant-specific fungal community-level differences on the same myrmecophytic host species. These differences may be shaped by ant behaviour in the domatia, and by ants vectoring fungi when they disperse to establish new colonies. The roles of the fungi with respect to the ants and their host plant remain to be determined.


Asunto(s)
Hormigas , Código de Barras del ADN Taxonómico , Hongos , Simbiosis , Animales , Femenino , Kenia
5.
FEMS Microbiol Ecol ; 99(12)2023 11 13.
Artículo en Inglés | MEDLINE | ID: mdl-37962959

RESUMEN

In the Arctic and subarctic, climate change is causing reduced snowpack extent and earlier snowmelt. Shallower snowpack decreases the thermal insulation of underlying soil and results in more freeze-thaw conditions reflective of dynamic air temperatures. The aim of this study was to determine the effect of alternative temperature regimes on overall microbial community structure and rhizosphere recruitment across representatives of three subarctic plant functional groups. We hypothesized that temperature regime would influence rhizosphere community structure more than plant type. Planted microcosms were established using a tree, forb, grass, or no plant control and subjected to either freeze-thaw cycling or static subzero temperatures. Our results showed rhizosphere communities exhibited reduced diversity compared to bulk soils, and were influenced by temperature conditions and to a lesser extent plant type. We found that plants have a core microbiome that is persistent under different winter temperature scenarios but also have temperature regime-specific rhizosphere microbes. Freeze-thaw cycling resulted in greater community shifts from the pre-incubation soils when compared to constant subzero temperature. This finding suggests that wintertime snowpack conditions may be a significant factor for plant-microbe interactions upon spring thaw.


Asunto(s)
Microbiota , Suelo , Suelo/química , Temperatura , Rizosfera , Congelación , Plantas , Microbiología del Suelo
6.
Ecol Evol ; 13(5): e10046, 2023 May.
Artículo en Inglés | MEDLINE | ID: mdl-37193112

RESUMEN

Africa has undergone a progressive aridification during the last 20 My that presumably impacted organisms and fostered the evolution of life history adaptations. We test the hypothesis that shift to living in ant nests and feeding on ant brood by larvae of phyto-predaceous Lepidochrysops butterflies was an adaptive response to the aridification of Africa that facilitated the subsequent radiation of butterflies in this genus. Using anchored hybrid enrichment we constructed a time-calibrated phylogeny for Lepidochrysops and its closest, non-parasitic relatives in the Euchrysops section (Poloyommatini). We estimated ancestral areas across the phylogeny with process-based biogeographical models and diversification rates relying on time-variable and clade-heterogeneous birth-death models. The Euchrysops section originated with the emerging Miombo woodlands about 22 million years ago (Mya) and spread to drier biomes as they became available in the late Miocene. The diversification of the non-parasitic lineages decreased as aridification intensified around 10 Mya, culminating in diversity decline. In contrast, the diversification of the phyto-predaceous Lepidochrysops lineage proceeded rapidly from about 6.5 Mya when this unusual life history likely first evolved. The Miombo woodlands were the cradle for diversification of the Euchrysops section, and our findings are consistent with the hypothesis that aridification during the Miocene selected for a phyto-predaceous life history in species of Lepidochrysops, with ant nests likely providing caterpillars a safe refuge from fire and a source of food when vegetation was scarce.

7.
Nat Commun ; 13(1): 1555, 2022 03 23.
Artículo en Inglés | MEDLINE | ID: mdl-35322033

RESUMEN

Protected areas are key to meeting biodiversity conservation goals, but direct measures of effectiveness have proven difficult to obtain. We address this challenge by using environmental DNA from leech-ingested bloodmeals to estimate spatially-resolved vertebrate occupancies across the 677 km2 Ailaoshan reserve in Yunnan, China. From 30,468 leeches collected by 163 park rangers across 172 patrol areas, we identify 86 vertebrate species, including amphibians, mammals, birds and squamates. Multi-species occupancy modelling shows that species richness increases with elevation and distance to reserve edge. Most large mammals (e.g. sambar, black bear, serow, tufted deer) follow this pattern; the exceptions are the three domestic mammal species (cows, sheep, goats) and muntjak deer, which are more common at lower elevations. Vertebrate occupancies are a direct measure of conservation outcomes that can help guide protected-area management and improve the contributions that protected areas make towards global biodiversity goals. Here, we show the feasibility of using invertebrate-derived DNA to estimate spatially-resolved vertebrate occupancies across entire protected areas.


Asunto(s)
Ciervos , Sanguijuelas , Animales , Biodiversidad , Bovinos , China , Conservación de los Recursos Naturales , Femenino , Mamíferos/genética , Ovinos , Vertebrados/genética
8.
Appl Environ Microbiol ; 77(12): 4249-52, 2011 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-21531831

RESUMEN

Symbioses are unique habitats for bacteria. We surveyed the spatial diversity of bacterial communities across multiple individuals of closely related lichens using terminal restriction fragment length polymorphism (T-RFLP) and pyrosequencing. Centers of lichens house richer, more consistent assemblages than species-poor and compositionally disparate lichen edges, suggesting that ecological succession plays a role in structuring these communities.


Asunto(s)
Bacterias/clasificación , Bacterias/aislamiento & purificación , Biodiversidad , Líquenes/microbiología , Bacterias/genética , Fenómenos Fisiológicos Bacterianos , ADN Bacteriano/genética , Tipificación Molecular , Polimorfismo de Longitud del Fragmento de Restricción , Análisis de Secuencia de ADN , Simbiosis
9.
J Trauma ; 69(1): 46-52, 2010 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-20622577

RESUMEN

BACKGROUND: Damage control laparotomy (DCL) improves outcomes when used in patients with severe hemorrhage. Correction of coagulopathy with close ratio resuscitation while limiting crystalloid forms a new methodology known as damage control resuscitation (DCR). We hypothesize a survival advantage in DCL patients managed with DCR when compared with DCL patients managed with conventional resuscitation efforts (CRE). METHODS: This study is a 4-year retrospective study of all DCL patients who required >or=10 units of packed red blood cells (PRBC) during surgery. A 2-year period after institution of DCR (DCL and DCR) was compared with the preceding 2 years (DCL and CRE). Univariate analysis of continuous data was done with Student's t test followed by multiple logistic regression. RESULTS: One Hundred twenty-four and 72 patients were managed during the DCL and CRE and DCL and DCR time periods, respectively. Baseline patient characteristics of age, Injury Severity Score, % penetrating, blood pressure, hemoglobin, base deficit, and INR were similar between groups. There was no difference in quantity of intraoperative PRBC utilization between DCL and CRE and DCL and DCR study periods: 21.7 units versus 25.5 units (p = 0.53); however, when compared with DCL and CRE group, patients in the DCL and DCR group received less intraoperative crystalloids, 4.7 L versus 14.2 L (p = 0.009); more fresh frozen plasma (FFP), 18.2 versus 6.4 (p = 0.002); a closer FFP to PRBC ratio, 1 to 1.2 versus 1 to 4.2 (p = 0.002); platelets to PRBC ratio, 1:2.3 versus 1:5.9 (0.002); shorter mean trauma intensive care unit length of stay, 11 days versus 20 days (p = 0.01); and greater 30-day survival, 73.6% versus 54.8% (p < 0.009). The addition of DCR to DCL conveyed a survival benefit (odds ratio; 95% confidence interval: 0.19 (0.05-0.33), p = 0.005). CONCLUSION: This is the first civilian study that analyses the impact of DCR in patients managed with DCL. During the DCL and DCR study period more PRBC, FFP, and platelets with less crystalloid solution was used intraoperatively. DCL and DCR were associated with a survival advantage and shorter trauma intensive care unit length of stay in patients with severe hemorrhage when compared with DCL and CRE.


Asunto(s)
Hemorragia/cirugía , Laparotomía/mortalidad , Resucitación/mortalidad , Heridas y Lesiones/cirugía , Heridas no Penetrantes/cirugía , Adulto , Transfusión Sanguínea , Femenino , Hemorragia/mortalidad , Humanos , Puntaje de Gravedad del Traumatismo , Laparotomía/métodos , Masculino , Análisis Multivariante , Análisis de Regresión , Soluciones para Rehidratación/uso terapéutico , Resucitación/métodos , Estudios Retrospectivos , Análisis de Supervivencia , Heridas y Lesiones/mortalidad , Heridas no Penetrantes/mortalidad , Heridas Penetrantes/mortalidad , Heridas Penetrantes/cirugía
10.
Am Surg ; 75(4): 284-6, 2009 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-19385285

RESUMEN

Charity Hospital (CH) was devastated by Hurricane Katrina and remains closed. Design and staffing of a new, temporary dedicated trauma hospital relied on data from prior experience at CH, updated census information, and a changed trauma demographic. The study objective was to analyze the new trauma program and evaluate changes in demographics, injury patterns, and outcomes between pre- (PK) and post-Katrina (POK) trauma populations. A retrospective review of trauma patients' demographics, anatomical variables, and physiological variables 6 months PK and POK was performed under an approved Institutional Review Board protocol. Trauma activation triage criteria between study periods were also analyzed. Continuous data comparisons between the two time periods were made with Student's t test. Dichotomous data were analyzed using chi2 test. The demographic of trauma patients is different in the POK interval, reflecting changes in the New Orleans population. Modification of triage criteria by the exclusion of mechanism as an activation criterion resulted in an increase of patients with higher acuity and Injury Severity Score, lower initial Glasgow Coma Score, and a higher proportion of penetrating mechanism. Outcome measures reflect longer length of stay (4.4 vs. 6.8 days, P < 0.0001) without a significant difference in mortality (6.0 vs 7.5, P = 0.227). Hospital data demonstrates that the POK trauma system was stressed by the increased acuity, penetrating injury, and number of procedures per patient (1.7 vs. 3.4). Resources should be directed toward patients requiring multidisciplinary care by increasing intensive care unit beds and operating room capacity. Future resource planning in the recovery phases of large-scale natural disasters should take into account these observations.


Asunto(s)
Tormentas Ciclónicas , Atención a la Salud/tendencias , Desastres , Etnicidad , Traumatismos Faciales/etnología , Admisión del Paciente/tendencias , Adulto , Atención a la Salud/métodos , Traumatismos Faciales/diagnóstico , Traumatismos Faciales/terapia , Humanos , Louisiana/epidemiología , Estudios Retrospectivos , Índices de Gravedad del Trauma
11.
J Trauma ; 67(1): 33-7; discussion 37-9, 2009 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-19590305

RESUMEN

BACKGROUND: Although hemostatic resuscitation with a 1:1 ratio of fresh-frozen plasma (FFP) to packed red blood cells (PRBC) after severe hemorrhage has been shown to improve survival, its benefit in patients with traumatic-induced coagulopathy (TIC) after >10 units of PRBC during operation has not been elucidated. We hypothesized that a survival benefit would occur when early hemostatic resuscitation was used intraoperatively after injury in patients with TIC. METHODS: A 7-year retrospective study of patients with emergency department diagnosis of TIC after transfusion of >10 units of PRBC in the operating room. TIC was defined as initial emergency department international normalized ratio > 1.2, prothrombin time > 16 seconds, and partial thromboplastin time > 50 seconds. Patients were divided into FFP:PRBC ratios of 1:1, 1:2, 1:3, and 1:4. Patients with diagnosis of TIC who received transfusion of both FFP and PRBC during surgery were included. Other variables evaluated included age, gender, mechanism of injury, initial base deficit, mean operative time, trauma intensive care unit length of stay (TICU LOS) and Injury Severity Score. The primary outcome measure evaluated was the impact of the early FFP:PRBC ratio on mortality. RESULTS: Four hundred thirty-five patients underwent emergency operations postinjury and received FFP with >10 units of PRBC in the operating room; 135 (31.0%) of these patients had TIC and 53 died (39.5% mortality). Mean operative time was 137 minutes (SD +/- 49). There were no differences with regard to age, gender, mechanism of injury, initial base deficit, or Injury Severity Score among all groups. A significant difference in mortality was found in patients who received >10 units of PRBC when FFP:PRBC ratio was 1:1 versus 1:4 (28.2% vs. 51.1%, p = 0.03). Intermediate mortality rates were noted in patients with 1:2 and 1:3 ratios (38% and 40%, respectively). From a linear regression model, 13 days of increased TICU LOS was observed among 1:4 group compared with 1:1 group (p < 0.01). CONCLUSION: TIC is common after severe injury and is associated with a high mortality in patients transfused with >10 units of PRBC during surgery. Early hemostatic resuscitation during first hours after injury improves survival with shorter TICU LOS in patients with TIC.


Asunto(s)
Transfusión de Componentes Sanguíneos/métodos , Coagulación Intravascular Diseminada/terapia , Hemostasis/fisiología , Técnicas Hemostáticas , Cuidados Intraoperatorios/métodos , Resucitación/métodos , Heridas y Lesiones/complicaciones , Adulto , Coagulación Intravascular Diseminada/etiología , Coagulación Intravascular Diseminada/mortalidad , Femenino , Estudios de Seguimiento , Humanos , Masculino , Estudios Retrospectivos , Tasa de Supervivencia/tendencias , Factores de Tiempo , Estados Unidos/epidemiología , Heridas y Lesiones/mortalidad , Heridas y Lesiones/cirugía
12.
PLoS One ; 14(7): e0219070, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31329604

RESUMEN

Knowing what animals eat is fundamental to our ability to understand and manage biodiversity and ecosystems, but researchers often must rely on indirect methods to infer trophic position and food intake. Using an approach that combines evidence from stable isotope analysis and DNA metabarcoding, we assessed the diet and trophic position of Anthene usamba butterflies, for which there are no known direct observations of larval feeding. An earlier study that analyzed adults rather than caterpillars of A. usamba inferred that this butterfly was aphytophagous, but we found that the larval guts of A. usamba and two known herbivorous lycaenid species contain chloroplast 16S sequences. Moreover, chloroplast barcoding revealed high sequence similarity between chloroplasts found in A. usamba guts and the chloroplasts of the Vachellia drepanolobium trees on which the caterpillars live. Stable isotope analysis provided further evidence that A. usamba caterpillars feed on V. drepanolobium, and the possibilities of strict herbivory versus limited omnivory in this species are discussed. These results highlight the importance of combining multiple approaches and considering ontogeny when using stable isotopes to infer trophic ecology where direct observations are difficult or impossible.


Asunto(s)
Mariposas Diurnas/fisiología , Dieta , Ecosistema , Animales , Hormigas/fisiología , Isótopos de Carbono , Código de Barras del ADN Taxonómico , ADN de Cloroplastos/genética , ADN de Cloroplastos/aislamiento & purificación , Fabaceae/química , Fabaceae/genética , Microbioma Gastrointestinal/genética , Herbivoria/genética , Larva/fisiología , Isótopos de Nitrógeno , Simbiosis
13.
Genome Announc ; 6(17)2018 Apr 26.
Artículo en Inglés | MEDLINE | ID: mdl-29700152

RESUMEN

Here, we describe four novel circular single-stranded DNA viruses discovered in fungus-farming termites (Odontotermes sp.). The viruses, named termite-associated circular virus 1 (TaCV-1) through TaCV-4, are most similar to members of the family Genomoviridae and were widely detected in African termite mounds.

14.
PeerJ ; 6: e5761, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30324030

RESUMEN

Viruses encoding a replication-associated protein (Rep) within a covalently closed, single-stranded (ss)DNA genome are among the smallest viruses known to infect eukaryotic organisms, including economically valuable agricultural crops and livestock. Although circular Rep-encoding ssDNA (CRESS DNA) viruses are a widespread group for which our knowledge is rapidly expanding, biased sampling toward vertebrates and land plants has limited our understanding of their diversity and evolution. Here, we screened terrestrial arthropods for CRESS DNA viruses and report the identification of 44 viral genomes and replicons associated with specimens representing all three major terrestrial arthropod lineages, namely Euchelicerata (spiders), Hexapoda (insects), and Myriapoda (millipedes). We identified virus genomes belonging to three established CRESS DNA viral families (Circoviridae, Genomoviridae, and Smacoviridae); however, over half of the arthropod-associated viral genomes are only distantly related to currently classified CRESS DNA viral sequences. Although members of viral and satellite families known to infect plants (Geminiviridae, Nanoviridae, Alphasatellitidae) were not identified in this study, these plant-infecting CRESS DNA viruses and replicons are transmitted by hemipterans. Therefore, members from six out of the seven established CRESS DNA viral families circulate among arthropods. Furthermore, a phylogenetic analysis of Reps, including endogenous viral sequences, reported to date from a wide array of organisms revealed that most of the known CRESS DNA viral diversity circulates among invertebrates. Our results highlight the vast and unexplored diversity of CRESS DNA viruses among invertebrates and parallel findings from RNA viral discovery efforts in undersampled taxa.

15.
Surg Infect (Larchmt) ; 18(3): 273-281, 2017 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-28085576

RESUMEN

BACKGROUND: Victims of traumatic injuries represent a population at risk for a wide variety of complications. Contact isolation (CI) is a set of restrictions designed to help prevent the transmission of medically significant organisms in the healthcare setting. A growing body of literature demonstrates that CI can have significant implications for the individual isolated patient. Our goal was to characterize the use of contact isolation at our Level I trauma center and investigate the association of CI with infectious complications. PATIENTS AND METHODS: An existing trauma database containing data on patients admitted at our Level I trauma center between January 1, 2011 and December 31, 2012, along with their contact isolation status, was queried. Demographics, injuries, and the presence of infections were collected. Diagnosis of pneumonia or UTI was based on clinical documentation in the patient's medical record. A chart review was performed to ascertain the reason for CI including specific organisms. Because of differences in patient demographics between the CI and non-CI groups, linear regression was performed to adjust for the effects of different variables. RESULTS: A total of 4,423 patients were admitted over this period. Of these, 4,318 (97.6%) had complete records and were included in the subsequent analysis. The CI was in place in 249 (5.8%) patients; 4,069 (94.2%) were not isolated. The number who had CI initiated for MRSA nasal colonization was 173 (69.5%). Twenty-two (8.9%) had no reason for CI documented. Pneumonia occurred in 190 (4.4%), 54 (21.7) in the CI group versus 136 (3.3%) in the non-CI group. Urinary tract infection (UTI) was diagnosed in 166 (3.8%), 48 (19.3%) in the CI group versus 118 (2.9%) in the non-CI group. Using logistic regression and excluding patients placed on contact isolation for the development of a new resistant nosocomial infection, CI, Injury Severity Score, gender, length of stay, and mechanical ventilation were identified as common covariates for pneumonia (PNA) and UTI. Chronic obstructive pulmonary disease COPD was specifically identified for PNA. Spinal cord injury, vertebral column injury and pelvic-urogenital injury were also significant for UTI. CONCLUSIONS: The development of pneumonia and UTI in patients with trauma was significantly associated with the use of CI. Because the majority of these patients had CI precautions in place for asymptomatic colonization, the CI provided them no direct benefit. Because the use of CI is associated with multiple negative outcomes, its use in the trauma population needs to be carefully re-evaluated.


Asunto(s)
Aislamiento de Pacientes , Neumonía/epidemiología , Neumonía/prevención & control , Infecciones Urinarias/epidemiología , Infecciones Urinarias/prevención & control , Heridas y Lesiones/complicaciones , Adulto , Femenino , Humanos , Masculino , Persona de Mediana Edad
16.
Artículo en Inglés | MEDLINE | ID: mdl-27481780

RESUMEN

DNA barcoding and metabarcoding methods have been invaluable in the study of interactions between host organisms and their symbiotic communities. Barcodes can help identify individual symbionts that are difficult to distinguish using morphological characters, and provide a way to classify undescribed species. Entire symbiont communities can be characterized rapidly using barcoding and especially metabarcoding methods, which is often crucial for isolating ecological signal from the substantial variation among individual hosts. Furthermore, barcodes allow the evolutionary histories of symbionts and their hosts to be assessed simultaneously and in reference to one another. Here, we describe three projects illustrating the utility of barcodes for studying symbiotic interactions: first, we consider communities of arthropods found in the ant-occupied domatia of the East African ant-plant Vachellia (Acacia) drepanolobium; second, we examine communities of arthropod and protozoan inquilines in three species of Nepenthes pitcher plant in South East Asia; third, we investigate communities of gut bacteria of South American ants in the genus Cephalotes Advances in sequencing and computation, and greater database connectivity, will continue to expand the utility of barcoding methods for the study of species interactions, especially if barcoding can be approached flexibly by making use of alternative genetic loci, metagenomes and whole-genome data.This article is part of the themed issue 'From DNA barcodes to biomes'.


Asunto(s)
Biodiversidad , Código de Barras del ADN Taxonómico , Simbiosis , Animales
18.
J Trauma Acute Care Surg ; 79(5): 833-7, 2015 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-26496110

RESUMEN

BACKGROUND: Contact isolation (CI) is a series of precautions used to prevent the transmission of medically significant infectious pathogens in the health care setting. Our institution's implementation of CI includes limiting patient movement to the assigned room. Our objective was to define the association between CI and venous thromboembolism (VTE) at our Level I trauma center. METHODS: Our institution's prospective trauma database was retrospectively queried for all patients admitted to the trauma service between January 1, 2011, and December 31, 2012. Data including demographics, Injury Severity Score (ISS), preexisting medical conditions, injury type, and VTE development were collected. CI status data were obtained from our institution's infection control database. χ2 was used to examine the unadjusted relationship between CI status and VTE. As the groups were not equivalent, logistic regression was then used to examine the relationship between CI and VTE while adjusting for relevant covariates including sex, age, ISS, and comorbidities. RESULTS: Of the 4,423 trauma patients admitted during the study period, 4,318 (97.6%) had complete records and were included in subsequent analyses. A total of 249 (5.8%) of the patients were on CI. VTE occurred in 44 patients (17.7%) on CI versus 141 patients (3.5%) who were not isolated (p < 0.0001; odds ratio, 6.0; 95% confidence interval, 4.1-8.6). With the use of lasso [least absolute shrinkage and selection operator] regression to adjust for patient risk factors, this relationship remained highly significant (p < 0.0001; odds ratio, 2.61; 95% confidence interval, 1.7-4.0). CONCLUSION: CI, ISS, hospital length of stay, and cardiac comorbidity were associated with VTE. After adjustment for other risk factors, CI remained most strongly associated with VTE. Although any medical intervention may come with unintended consequences, the risks and benefits of CI in this population need to be reevaluated. Further study is planned to identify opportunities to mitigate this increased VTE risk. LEVEL OF EVIDENCE: Prognostic/epidemiologic study, level III; therapeutic study, level IV.


Asunto(s)
Trazado de Contacto/métodos , Tromboembolia Venosa/diagnóstico , Tromboembolia Venosa/epidemiología , Heridas y Lesiones/diagnóstico , Adulto , Distribución por Edad , Anticoagulantes/uso terapéutico , Bases de Datos Factuales , Femenino , Estudios de Seguimiento , Humanos , Incidencia , Puntaje de Gravedad del Traumatismo , Tiempo de Internación , Modelos Logísticos , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Factores de Riesgo , Distribución por Sexo , Estadísticas no Paramétricas , Centros Traumatológicos , Tromboembolia Venosa/tratamiento farmacológico , Tromboembolia Venosa/etiología , Heridas y Lesiones/complicaciones , Heridas y Lesiones/cirugía , Adulto Joven
19.
Am J Surg ; 188(3): 225-9, 2004 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-15450824

RESUMEN

BACKGROUND: Surgical resident education is entering a critical era of achieving core competencies despite work hour restrictions. An assessment of on-call activity is needed to maximize educational merit. METHODS: A time-motion study of resident on-call activity was performed at a university medical center and an urban affiliate hospital. Residents were followed by "shadow" residents who concurrently recorded resident activity. RESULTS: Activities of daily living and patient evaluation comprised the majority of on-call activity. Residents slept a median of 200 minutes per night. Cross-coverage activities accounted for 41% of pages and 19% of patient evaluation. Direct patient contact comprised only 7% of call night duties. Communication activity occupied 15% of total minutes, and a mean of 16 pages were received nightly. Significant differences in activities existed between resident levels and hospitals. CONCLUSIONS: Call activity consists primarily of activities of daily living, patient evaluation, and communication. Sleep accounts for nearly one third of all on-call activity. These data may be useful in improving both patient care and resident call experience.


Asunto(s)
Atención Posterior/organización & administración , Cirugía General/organización & administración , Hospitales de Enseñanza , Internado y Residencia/organización & administración , Estudios de Tiempo y Movimiento , Educación de Postgrado en Medicina/organización & administración , Humanos , Cuidados Nocturnos/organización & administración , Admisión y Programación de Personal/organización & administración , Tolerancia al Trabajo Programado , Carga de Trabajo
20.
J Trauma Acute Care Surg ; 77(1): 83-8; discussion 88, 2014 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-24977760

RESUMEN

BACKGROUND: The changing face of American health care demands careful scrutiny of resource allocation. The impact of the surgical intensivist model on general surgical quality measures has not been studied. Our objective was to investigate the relationship between surgical critical care staffing and indicators of general surgical quality measured by the National Surgical Quality Improvement Program (NSQIP). METHODS: We retrospectively examined the number of attending surgical intensivists at our tertiary care center biannually from January 2008 through June 2012. Risk-adjusted indicators of general surgical quality were captured and reported semiannually by NSQIP. Mortality, overall morbidity, patients on ventilator for more than 48 hours, unplanned intubations, and venous thromboembolism were included. Student's t test was used to compare the staffing levels and associated NSQIP odds ratios of a 3-year control period of full commitment with a 2-year period following significant provider attrition. RESULTS: The number of full-time surgical intensivists ranged from 2 to 8, with a period of rapid decline in late 2010 to early 2011 followed by slow recovery. There was a mean of 6.6 surgical intensivists during the 3 years before the decline and a mean of 4 in the 2 years after the decline and recovery (p < 0.005). This period of decline was associated with a significant increase in the odds ratio of ventilation for more than 48 hours (before, 0.936; after, 1.87; p = 0.0086) and of venous thromboembolism (before, 0.844; after 1.43; p = 0.0268). A trend in increased unplanned intubations was also observed. Overall morbidity and mortality were not affected. Notably, quality indicators seemed to rapidly approach baseline levels as new surgical intensivists were recruited. CONCLUSION: Institutional commitment to recruitment and retention of a surgical critical care team leads to improved NSQIP general surgery quality measures. LEVEL OF EVIDENCE: Care management study, level IV.


Asunto(s)
Cuidados Críticos , Médicos Hospitalarios , Admisión y Programación de Personal/normas , Indicadores de Calidad de la Atención de Salud , Adulto , Médicos Hospitalarios/normas , Humanos , Admisión y Programación de Personal/estadística & datos numéricos , Garantía de la Calidad de Atención de Salud , Mejoramiento de la Calidad , Respiración Artificial/estadística & datos numéricos , Estudios Retrospectivos , Recursos Humanos
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