RESUMO
Soil is an immense habitat for diverse organisms across the tree of life, but just how many organisms live in soil is surprisingly unknown. Previous efforts to enumerate soil biodiversity consider only certain types of organisms (e.g., animals) or report values for diverse groups without partitioning species that live in soil versus other habitats. Here, we reviewed the biodiversity literature to show that soil is likely home to 59 ± 15% of the species on Earth. We therefore estimate an approximately two times greater soil biodiversity than previous estimates, and we include representatives from the simplest (microbial) to most complex (mammals) organisms. Enchytraeidae have the greatest percentage of species in soil (98.6%), followed by fungi (90%), Plantae (85.5%), and Isoptera (84.2%). Our results demonstrate that soil is the most biodiverse singular habitat. By using this estimate of soil biodiversity, we can more accurately and quantitatively advocate for soil organismal conservation and restoration as a central goal of the Anthropocene.
Assuntos
Biodiversidade , Solo , Animais , Ecossistema , Fungos , Plantas , MamíferosRESUMO
Microbial carbon use efficiency (CUE)-the balance between microbial growth and respiration-strongly impacts microbial mediated soil carbon storage and is sensitive to many well-studied abiotic environmental factors. However, surprisingly, little work has examined how biotic interactions in soil may impact CUE. Here, we review the theoretical and empirical lines of evidence exploring how biotic interactions affect CUE through the lens of life history strategies. Fundamentally, the CUE of a microbial population is constrained by population density and carrying capacity, which, when reached, causes species to grow more quickly and less efficiently. When microbes engage in interspecific competition, they accelerate growth rates to acquire limited resources and release secondary chemicals toxic to competitors. Such processes are not anabolic and thus constrain CUE. In turn, antagonists may activate one of a number of stress responses that also do not involve biomass production, potentially further reducing CUE. In contrast, facilitation can increase CUE by expanding species realized niches, mitigating environmental stress and reducing production costs of extracellular enzymes. Microbial interactions at higher trophic levels also influence CUE. For instance, predation on microbes can positively or negatively impact CUE by changing microbial density and the outcomes of interspecific competition. Finally, we discuss how plants select for more or less efficient microbes under different contexts. In short, this review demonstrates the potential for biotic interactions to be a strong regulator of microbial CUE and additionally provides a blueprint for future research to address key knowledge gaps of ecological and applied importance for carbon sequestration.
Assuntos
Carbono , Solo , Biomassa , Interações MicrobianasRESUMO
Fungal decomposition of soil organic matter depends on soil nitrogen (N) availability. This ecosystem process is being jeopardized by changes in N inputs that have resulted from a tripling of atmospheric N deposition in the last century. Soil fungi are impacted by atmospheric N deposition due to higher N availability, as soils are acidified, or as micronutrients become increasingly limiting. Fungal communities that persist with chronic N deposition may be enriched with traits that enable them to tolerate environmental stress, which may trade-off with traits enabling organic matter decomposition. We hypothesized that fungal communities would respond to N deposition by shifting community composition and functional gene abundances toward those that tolerate stress but are weak decomposers. We sampled soils at seven eastern US hardwood forests where ambient N deposition varied from 3.2 to 12.6 kg N ha-1 year-1 , five of which also have experimental plots where atmospheric N deposition was simulated through fertilizer application treatments (25-50 kg N ha-1 year-1 ). Fungal community and functional responses to fertilizer varied across the ambient N deposition gradient. Fungal biomass and richness increased with simulated N deposition at sites with low ambient deposition and decreased at sites with high ambient deposition. Fungal functional genes involved in hydrolysis of organic matter increased with ambient N deposition while genes involved in oxidation of organic matter decreased. One of four genes involved in generalized abiotic stress tolerance increased with ambient N deposition. In summary, we found that the divergent response to simulated N deposition depended on ambient N deposition levels. Fungal biomass, richness, and oxidative enzyme potential were reduced by N deposition where ambient N deposition was high suggesting fungal communities were pushed beyond an environmental stress threshold. Fungal community structure and function responses to N enrichment depended on ambient N deposition at a regional scale.
Assuntos
Micobioma , Nitrogênio , Ecossistema , Nitrogênio/análise , Solo , Microbiologia do Solo , ÁrvoresRESUMO
BACKGROUND: Teenage pregnancy is a serious public health and social problem, with 95% occurring in developing countries. The aim of the study was to investigate the behavioural, familial and social factors associated with teenage pregnancy among girls aged 13-19 years in Lira District, Uganda. METHODS: Primary data from a case-control study of teenage girls (aged 13-19 years) in Lira District, Uganda was analysed. A Structured questionnaire was administered using face-to-face interviews to collect data on 495 participants, identified through simple random sampling from 32 villages in two counties in Lira District. Data analyses were done using SPSS Statistics 23 for descriptive, bivariate (i.e. Chi-square tests) and multivariable analyses (i.e. logistics regression) used for determining independent associations. RESULTS: A total of 495 teenage girls participated in the study, however, final analyses were undertaken for 480 respondents. At bivariable analysis, all variables except alcohol consumption were significantly associated with teenage pregnancy. Among the behavioural factors assessed, multivariable analyses showed that having multiple sexual partners, frequent sex and irregular contraceptive use increased the likelihood of teenage pregnancy. Among familial factors, being married was found to increase the likelihood of teenage pregnancy. Peer pressure, sexual abuse and lack of control over sex was observed to increase the likelihood of teenage pregnancy. CONCLUSIONS: Demographic, behavioural, familial and social factors are important predictors of teenage pregnancy in Lira District. Interventions focussing on: retaining pregnant and married girls at school, information on sexual and reproductive health of teenage girls, improving access to and information about contraceptive use among teenage girls, improving socio-economic status of households, and law enforcement on sexual abuse among girls may come a long way to improving adolescent sexual and health services in the low-income settings.
Assuntos
Comportamento Contraceptivo/estatística & dados numéricos , Países em Desenvolvimento/estatística & dados numéricos , Gravidez na Adolescência/estatística & dados numéricos , Comportamento Sexual/estatística & dados numéricos , Adolescente , Estudos de Casos e Controles , Feminino , Humanos , Estado Civil , Influência dos Pares , Autonomia Pessoal , Gravidez , Fatores de Risco , Delitos Sexuais/estatística & dados numéricos , Parceiros Sexuais , Inquéritos e Questionários , Uganda , Adulto JovemRESUMO
AIM: Sepsis is multifactorial and potentially devastating for preterm neonates. Changes in surfactant protein-D (SP-D), phosphatidylcholine (PC) and PC molecular species during infection may indicate innate immunity or inflammation during sepsis. We aimed to compare these important pulmonary molecules in ventilated neonates without or with sepsis. METHODS: Endotracheal aspirates were collected from preterm neonates born at 23-35 weeks and admitted to the neonatal intensive care unit at the John Radcliffe Hospital, Oxford, UK, from October 2000 to March 2002. Samples were collected at one day to 30 days and analysed for SP-D, total PC and PC molecular species concentrations using enzyme-linked immunosorbent assay and mass spectrometry. RESULTS: We found that 8/54 (14.8%) neonates developed sepsis. SP-D (p < 0.0001), mono- and di-unsaturated PC were significantly increased (p = 0.05), and polyunsaturated PC was significantly decreased (p < 0.01) during sepsis compared to controls. SP-D:PC ratios were significantly increased during sepsis (p < 0.001), and SP-D concentrations were directly related to gestational age in neonates with sepsis (r2 = 0.389, p < 0.01). CONCLUSION: Increased SP-D levels and changes in PC molecular species during sepsis were consistent with direct or indirect pulmonary inflammatory processes. Very preterm neonates we able to mount an acute inflammatory innate immune response to infectious challenges, despite low levels of surfactant proteins at birth.
Assuntos
Sepse Neonatal/metabolismo , Proteína D Associada a Surfactante Pulmonar/metabolismo , Estudos de Casos e Controles , Feminino , Idade Gestacional , Humanos , Recém-Nascido , Recém-Nascido Prematuro , Masculino , Sepse Neonatal/diagnóstico , Sepse Neonatal/terapia , Fosfatidilcolinas/metabolismoRESUMO
BACKGROUND: Researchers have attempted to operationalise objective measures of cognitive fatigability in multiple sclerosis (MS) to overcome the perceived subjectivity of patient-reported outcomes of fatigue (PROs). Measures of cognitive fatigability examine decrements in performance during sustained neurocognitive tasks. OBJECTIVE: This personal viewpoint briefly summarises available evidence for measures of cognitive fatigability in MS and considers their overall utility. RESULTS: Studies suggest there may be a construct that is distinct from self-reported fatigue, reflecting a new potential intervention target. However, assessments vary and findings across and within measures are inconsistent. Few measures have been guided by a coherent theory, and those identified are likely to be influenced by other confounds, such as cognitive impairment caused more directly by disease processes, depression and assessment biases. CONCLUSION: Future research may benefit from (a) developing a guiding theory of cognitive fatigability, (b) examining ecological and construct validity of existing assessments and (c) exploring whether the more promising cognitive fatigability measures are correlated with impaired functioning after accounting for possible confounds. Given the issues raised, we caution that our purposes as researchers may be better served by continuing our search for a more objective cognitive fatigability construct that runs in parallel with improving, rather than devaluing, current PROs.
Assuntos
Disfunção Cognitiva/diagnóstico , Fadiga Mental/diagnóstico , Esclerose Múltipla/complicações , Testes Neuropsicológicos/normas , Disfunção Cognitiva/etiologia , Humanos , Fadiga Mental/etiologiaRESUMO
Susceptibility to brood pathogens in eusocial stingless bees (Meliponini), alternative pollinators to honey bees, is unknown. Brood losses in managed colonies of the Australian stingless bee, Tetragonula carbonaria, were studied over 20months. We isolated a disease-causing bacterium, Lysinibacillus sphaericus (Firmicutes, Bacillaceae), from worker and queen larvae, brood cell provisions and honey stores. Pathogenicity experiments confirmed this bacterium as the causal organism. It took 22days from infection to first appearance of brood disease symptoms. This is the first confirmed record of a brood pathogen in stingless bees.
Assuntos
Abelhas/microbiologia , Colapso da Colônia/microbiologia , Animais , Austrália , FirmicutesRESUMO
OBJECTIVE: Commotio cordis, sudden death with chest impact, occurs clinically despite chest wall protectors worn in sports. In an experimental model of commotio cordis, commercially available chest wall protectors failed to prevent ventricular fibrillation (VF). The goal of the current investigation was to develop a chest wall protector effective in the prevention of commotio cordis. DESIGN: In the Tufts experimental model of commotio cordis the ability of chest protectors to prevent VF was assessed. Impacts were delivered with a 40-mph lacrosse ball, timed to the vulnerable period for VF. INTERVENTION: A chest wall protector or no chest wall protector (control) was randomly assigned to be placed over the chest. Four iterative series of 2 to 4 different chest wall material combinations were assessed. Materials included 3 different foams (Accelleron [Unequal Technologies, Glen Mills, PA], closed cell high density foam; Airilon [Unequal Technologies, Glen Mills, PA], closed cell low density soft foam; and an open cell memory foam) that were adhered to a layer of TriDur (Unequal Technologies, Glen Mills, PA), a flexible elastomeric coated aramid that was bonded to a semirigid polypropylene polymer (ImpacShield, Unequal Technologies, Glen Mills, PA). MAIN OUTCOME MEASURE: Induction of VF by chest wall impact was the primary outcome. RESULTS: Of 80 impacts without chest protectors, 43 (54%) resulted in VF. Ventricular fibrillation with chest protectors ranged from a high of 60% to a low of 5%. Of 12 chest protectors assessed, only 3 significantly lowered the risk of VF compared with impacts without chest protectors. These 3 chest protectors were combinations of Accelleron, Airilon, TriDur, and ImpacShield of different thicknesses. Protection increased linearly with the thicker combinations. CONCLUSIONS: Effective protection against VF with chest wall protection can be achieved in an experimental model of commotio cordis. CLINICAL RELEVANCE: Chest protector designs incorporating these novel materials will likely be effective in the prevention of commotio cordis on the playing field.
Assuntos
Traumatismos em Atletas/prevenção & controle , Morte Súbita Cardíaca/etiologia , Roupa de Proteção , Animais , Morte Súbita Cardíaca/prevenção & controle , Masculino , Suínos , Fibrilação Ventricular/etiologia , Fibrilação Ventricular/prevenção & controleRESUMO
Transient abnormal myelopoiesis (TAM), a preleukemic disorder unique to neonates with Down syndrome (DS), may transform to childhood acute myeloid leukemia (ML-DS). Acquired GATA1 mutations are present in both TAM and ML-DS. Current definitions of TAM specify neither the percentage of blasts nor the role of GATA1 mutation analysis. To define TAM, we prospectively analyzed clinical findings, blood counts and smears, and GATA1 mutation status in 200 DS neonates. All DS neonates had multiple blood count and smear abnormalities. Surprisingly, 195 of 200 (97.5%) had circulating blasts. GATA1 mutations were detected by Sanger sequencing/denaturing high performance liquid chromatography (Ss/DHPLC) in 17 of 200 (8.5%), all with blasts >10%. Furthermore low-abundance GATA1 mutant clones were detected by targeted next-generation resequencing (NGS) in 18 of 88 (20.4%; sensitivity â¼0.3%) DS neonates without Ss/DHPLC-detectable GATA1 mutations. No clinical or hematologic features distinguished these 18 neonates. We suggest the term "silent TAM" for neonates with DS with GATA1 mutations detectable only by NGS. To identify all babies at risk of ML-DS, we suggest GATA1 mutation and blood count and smear analyses should be performed in DS neonates. Ss/DPHLC can be used for initial screening, but where GATA1 mutations are undetectable by Ss/DHPLC, NGS-based methods can identify neonates with small GATA1 mutant clones.
Assuntos
Células Clonais/metabolismo , Síndrome de Down/genética , Mutação , Doença Aguda , Transformação Celular Neoplásica/genética , Transformação Celular Neoplásica/patologia , Cromatografia Líquida de Alta Pressão/métodos , Células Clonais/patologia , Análise Mutacional de DNA/métodos , Síndrome de Down/sangue , Fator de Transcrição GATA1 , Testes Genéticos/métodos , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Humanos , Recém-Nascido , Leucemia Mieloide/sangue , Leucemia Mieloide/diagnóstico , Leucemia Mieloide/genética , Mielopoese/genética , Triagem Neonatal/métodos , Células Neoplásicas Circulantes/metabolismo , Células Neoplásicas Circulantes/patologia , Pré-Leucemia/sangue , Pré-Leucemia/diagnóstico , Pré-Leucemia/genética , Reprodutibilidade dos Testes , Fatores de Risco , Sensibilidade e EspecificidadeRESUMO
PURPOSE: Pedicle screw instrumentation provides optimal stabilization of the cervical spine complex, but is associated with risk of neurovascular injury. Sex and ethnic disparities may compromise safe and accurate screw placement. Therefore, a comprehensive analysis of pedicle dimensions derived from computed tomography scans is pertinent for our multi-ethnic population. METHODS: Cervical spine CT of 50 patients without significant cervical spine pathology was selected. Pedicle width (PW), pedicle height (PH) and pedicle transverse angle (PTA) from C3 to C7 were measured and subsequently analyzed for sex and ethnic differences. RESULTS: The smallest mean PW was at C4 in males and C3 in females. Mean PW for males was significantly greater than females at all levels (P < 0.05). 8 % of our population had at least one PW < 4.00 mm. At C5, C6 and C7 there is zero percent incidence of PW < 4.00 mm. The mean PH in males was significantly greater than females at all levels (P < 0.05), but no statistically significant sex differences in mean PTA values were found. There were significant ethnic differences in mean PW of males at C4, C5 and C7 (P < 0.05) and mean PH of females at C3, C4 and C7 (P < 0.05). CONCLUSIONS: Transpedicular screw fixation is generally feasible in our population except for 8 % with at least one PW < 4.00 mm. However, in view of significant sex and ethnic morphometric variability, pre-operative CT evaluation together with image-guided screw placement is highly advised to ensure safety and accuracy.
Assuntos
Vértebras Cervicais/anatomia & histologia , Vértebras Cervicais/diagnóstico por imagem , Parafusos Pediculares , Adulto , Idoso , Povo Asiático , Vértebras Cervicais/cirurgia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Caracteres Sexuais , Singapura , Tomografia Computadorizada por Raios X , Adulto JovemRESUMO
BACKGROUND: Bacterial meningitis remains a major cause of morbidity and mortality in young infants. Understanding the epidemiology and burden of disease is important. METHODS: Prospective, enhanced, national population-based active surveillance was undertaken to determine the incidence, etiology, and outcome of bacterial meningitis in infants aged <90 days in the United Kingdom and Ireland. RESULTS: During July 2010-July 2011, 364 cases were identified (annual incidence, 0.38/1000 live births; 95% confidence interval [CI], .35-.42). In England and Wales, the incidence of confirmed neonatal bacterial meningitis was 0.21 (n = 167; 95% CI, .18-.25). A total of 302 bacteria were isolated in 298 (82%) of the cases. The pathogens responsible varied by route of admission, gestation at birth, and age at infection. Group B Streptococcus (GBS) (150/302 [50%]; incidence, 0.16/1000 live births; 95% CI, .13-.18) and Escherichia coli (41/302 [14%]; incidence, 0.04/1000; 95% CI, .03-.06) were responsible for approximately two-thirds of identified bacteria. Pneumococcal (28/302 [9%]) and meningococcal (23/302 [8%]) meningitis were rare in the first month, whereas Listeria meningitis was seen only in the first month of life (11/302 [4%]). In hospitalized preterm infants, the etiology of both early- and late-onset meningitis was more varied. Overall case fatality was 8% (25/329) and was higher for pneumococcal meningitis (5/26 [19%]) than GBS meningitis (7/135 [5%]; P = .04) and for preterm (15/90 [17%]) compared with term (10/235 [4%]; P = .0002) infants. CONCLUSIONS: The incidence of bacterial meningitis in young infants remains unchanged since the 1980s and is associated with significant case fatality. Prevention strategies and guidelines to improve the early management of cases should be prioritized.
Assuntos
Meningites Bacterianas/epidemiologia , Meningites Bacterianas/etiologia , Vigilância da População , Feminino , Humanos , Incidência , Lactente , Recém-Nascido , Irlanda/epidemiologia , Masculino , Meningites Bacterianas/diagnóstico , Meningites Bacterianas/microbiologia , Mortalidade , Avaliação de Resultados da Assistência ao Paciente , Estudos Prospectivos , Fatores de Risco , Reino Unido/epidemiologiaRESUMO
Haemophilus influenzae is a Gram-negative bacillus and a frequent commensal of the human nasopharynx. Earlier work demonstrated that in H. influenzae type b, l-lactate metabolism is associated with serum resistance and in vivo survival of the organism. To further gain insight into lactate utilization of the non-typeable (NTHi) isolate 2019 and laboratory prototype strain Rd KW20, deletion mutants of the l-lactate dehydrogenase (lctD) and permease (lctP) were generated and characterized. It is shown, that the apparent KM of l-lactate uptake is 20.1µM as determined for strain Rd KW20. Comparison of the COPD isolate NTHi 2019-R with the corresponding lctP knockout strain for survival in human serum revealed no lactate dependent serum resistance. In contrast, we observed a 4-fold attenuation of the mutant strain in a murine model of nasopharyngeal colonization. Characterization of lctP transcriptional control shows that the lactate utilization system in H. influenzae is not an inductor inducible system. Rather negative feedback regulation was observed in the presence of l-lactate and this is dependent on the ArcAB regulatory system. Additionally, for 2019 it was found that lactate may have signaling function leading to increased cell growth in late log phase under conditions where no l-lactate is metabolized. This effect seems to be ArcA independent and was not observed in strain Rd KW20. We conclude that l-lactate is an important carbon-source and may act as host specific signal substrate which fine tunes the globally acting ArcAB regulon and may additionally affect a yet unknown signaling system and thus may contribute to enhanced in vivo survival.
Assuntos
Haemophilus influenzae/fisiologia , Ácido Láctico/metabolismo , Animais , Atividade Bactericida do Sangue , Modelos Animais de Doenças , Metabolismo Energético , Deleção de Genes , Perfilação da Expressão Gênica , Regulação Bacteriana da Expressão Gênica , Infecções por Haemophilus/microbiologia , Haemophilus influenzae/genética , Haemophilus influenzae/metabolismo , L-Lactato Desidrogenase/genética , L-Lactato Desidrogenase/metabolismo , Proteínas de Membrana Transportadoras/genética , Proteínas de Membrana Transportadoras/metabolismo , Camundongos Endogâmicos BALB C , Viabilidade Microbiana , Nasofaringe/microbiologia , Soro/microbiologia , VirulênciaRESUMO
iPhone apps are a widely utilised technology that have recently been identified as a useful medium for health research, clinical interventions and education. While some researchers have discussed advances in app technology, others promote specific apps that are not free to access. To our knowledge, no study has conducted a review of current, free iPhone apps related to psychology, psychiatry and mental health. Therefore, we conducted a pilot, web-based review exploring free iPhone apps using a replicable search strategy within the iTunes Store search function. A selection of apps were selected and subjectively assessed in terms of their usability, utility, graphics, and associated costs for the consumer. We concluded that the apps reviewed, though novel, are limited in their scope and utility. We also note a significant gap in more scientific, evidence-based app technology, and pose some pertinent ethical questions when developing future psych-related apps.
Assuntos
Computadores de Mão , Saúde Mental , Aplicativos Móveis , HumanosRESUMO
Forest soils harbor hyper-diverse microbial communities which fundamentally regulate carbon and nutrient cycling across the globe. Directly testing hypotheses on how microbiome diversity is linked to forest carbon storage has been difficult, due to a lack of paired data on microbiome diversity and in situ observations of forest carbon accumulation and storage. Here, we investigated the relationship between soil microbiomes and forest carbon across 238 forest inventory plots spanning 15 European countries. We show that the composition and diversity of fungal, but not bacterial, species is tightly coupled to both forest biotic conditions and a seven-fold variation in tree growth rates and biomass carbon stocks when controlling for the effects of dominant tree type, climate, and other environmental factors. This linkage is particularly strong for symbiotic endophytic and ectomycorrhizal fungi known to directly facilitate tree growth. Since tree growth rates in this system are closely and positively correlated with belowground soil carbon stocks, we conclude that fungal composition is a strong predictor of overall forest carbon storage across the European continent.
Assuntos
Micobioma , Carbono , Microbiologia do Solo , Florestas , Árvores/microbiologia , SoloRESUMO
Despite the government efforts to reduce the high fertility levels and increase the uptake of family planning services in Uganda, family planning use was still low at 30% in 2020 which was the lowest in the East African region. This study was undertaken to determine the prevalence and factors associated with the uptake of family planning methods among women of reproductive age in Uganda. This community-based cross-sectional study utilized secondary data from the Uganda Demographic and Health Survey (UDHS) of 2016. The survey data was downloaded from the Measure Demographic Health Survey website after data use permission was granted. Data was collected from a representative sample of women of the reproductive age group (15-49 years) from all 15 regions in Uganda. A total of 19,088 eligible women were interviewed but interviews were completed with 18,506 women. Data analysis was performed using SPSS statistical software version 32.0 where univariable, bivariable, and multivariable analyses were conducted. The prevalence of family planning use was found to be 29.3% and that of modern contraceptive use was found to be 26.6%. Multivariable analysis showed higher odds of current family planning use among older women (40-44 years) (aOR = 2.09, 95% CI: 1.40-3.12); women who had attained the secondary level of education (aOR = 1.91, 95% CI: 1.32-2.76); those living in households with the highest wealth index (aOR = 1.87, 95% CI: 1.29-2.72); and awareness of the availability of family planning methods (aOR = 1.41, 95% CI: 1.17-1.72). In conclusion, the study suggests improving women's education attainment, socio-economic position, and awareness may help increase use in the population.
RESUMO
Following a disturbance, dispersal shapes community composition as well as ecosystem structure and function. For fungi, dispersal is often wind or mammal facilitated, but it is unclear whether these pathways are complementary or redundant in the taxa they disperse and the ecosystem functions they provide. Here, we compare the diversity and morphology of fungi dispersed by wind and three rodent species in recently harvested forests using a combination of microscopy and Illumina sequencing. We demonstrate that fungal communities dispersed by wind and small mammals differ in richness and composition. Most wind-dispersed fungi are wood saprotrophs, litter saprotrophs, and plant pathogens, whereas fungi dispersed in mammal scat are primarily mycorrhizal, soil saprotrophs, and unspecified saprotrophs. We note substantial dispersal of truffles and agaricoid mushrooms by small mammals, and dispersal of agaricoid mushrooms, crusts, and polypores by wind. In addition, we find mammal-dispersed spores are larger than wind-dispersed spores. Our findings suggest that wind- and small-mammal-facilitated dispersal are complementary processes and highlight the role of small mammals in dispersing mycorrhizal fungi, particularly following disturbances such as timber harvest.
Assuntos
Ecossistema , Micorrizas , Animais , Vento , Florestas , Mamíferos , Roedores , Microbiologia do Solo , Fungos , Solo , Esporos FúngicosRESUMO
BACKGROUND: Atrial fibrillation (AF) affects millions of Americans each year and can lead to high levels of resource utilization through emergency department (ED) visits and inpatient stays. HYPOTHESIS: We hypothesized that referral of patients to a dedicated Center for AF from the ED would reduce costs of care. METHODS: The University of Pittsburgh Center for AF serves as a rapid referral center for patients with AF to avoid unnecessary inpatient admissions and provide specialized care. Patients that presented to the ED with AF and met prespecified criteria were directed to rapid outpatient follow-up instead of inpatient admission. The primary outcome of interest was 30-day total costs. Secondary outcomes included outpatient costs, inpatient costs, 90-day costs, and inpatient stay characteristics. RESULTS: We identified 96 patients (median age 65, 38% women) referred to the center for AF for a new diagnosis of AF between October 2017 and December 2019 and matched 96 control patients. After 30 days of follow-up, patients referred to the center for AF had a lower average cost ($619 vs. $1252, p < 0.001) compared to controls, driven by lower costs of ED care tempered by slightly higher outpatient costs. Thirty-day admissions and lengths of stay were also lower. These differences were persistent at 90 days. CONCLUSION: Directing patients with AF that present to the ED to follow-up at a dedicated Center for AF significantly reduced overall costs, while reducing subsequent inpatient admissions and total lengths of stay in the hospital.
Assuntos
Fibrilação Atrial , Serviços Médicos de Emergência , Humanos , Feminino , Estados Unidos , Idoso , Masculino , Fibrilação Atrial/diagnóstico , Fibrilação Atrial/epidemiologia , Fibrilação Atrial/terapia , Estudos Retrospectivos , Hospitalização , Serviço Hospitalar de EmergênciaRESUMO
In patients with left ventricular (LV) dysfunction, the risk of death or heart failure hospitalizations (HFHs) increases with worsening ejection fraction (EF). Whether the relative contribution of atrial fibrillation (AF) to outcomes is more pronounced in patients with worse EF is not confirmed. The present study aimed to investigate the relative influence of AF on the outcome of cardiomyopathy patients by severity of LV dysfunction. In this observational study, data from 18,003 patients with EF ≤50% seen at a large academic institution between 2011 and 2017 were analyzed. Patients were stratified by EF quartiles (EF<25%, 25%≤EF<35%, 35%≤EF<40%, and EF≥40%, for quartiles 1, 2, 3, and 4, respectively). and followed to the end point of death or HFH. Outcomes of AF versus non-AF patients were compared within each EF quartile. During a median follow-up of 3.35 years, 8,037 patients (45%) died and 7,271 (40%) had at least 1 HFH. Rates of HFH and all-cause mortality increased as EF decreased. The hazard ratios (HRs) of death or HFH for AF versus non-AF patients increased steadily with increasing EF (HR of 1.22, 1.27, 1.45, 1.50 for quartiles 1, 2, 3, and 4, respectively, p = 0.045) driven primarily by the risk of HFH (HR of 1.26, 1.45, 1.59, 1.69 for quartiles 1, 2, 3, and 4, respectively, p = 0.045). In conclusion, in patients with LV dysfunction, the detrimental influence of AF on the risk of HFH is more pronounced in those with more preserved EF. Mitigation strategies for AF with the goal of decreasing HFH may be more impactful in patients with more preserved LV function.
Assuntos
Fibrilação Atrial , Cardiomiopatias , Insuficiência Cardíaca , Disfunção Ventricular Esquerda , Humanos , Fibrilação Atrial/complicações , Fibrilação Atrial/epidemiologia , Volume Sistólico , Cardiomiopatias/complicações , Disfunção Ventricular Esquerda/etiologia , Função Ventricular Esquerda , Insuficiência Cardíaca/complicações , Insuficiência Cardíaca/epidemiologiaRESUMO
Group B Streptococcus (GBS) is a leading cause of neonatal meningitis and septicemia. The ability of this organism to survive inside phagocytic cells is poorly understood but thought to be an important step for the establishment of disease in the host. Here, we demonstrate that GBS shows prolonged survival within J774 macrophages and that the capacity to survive is not significantly changed across a diverse range of strains representing different serotypes, multilocus sequence types (MLST), and sites of clinical isolation. Using staining for the lysosome-associated membrane protein (LAMP) and by pharmacological inhibition of phagosome acidification, we demonstrate that streptococci reside in a phagosome and that acidification of the phagosome is required for GBS to survive intracellularly. Moreover, we show that the GBS two-component system CovS/CovR, which is the major acid response regulator in this organism, is required for survival inside the phagosome.
Assuntos
Proteínas de Bactérias/metabolismo , Regulação Bacteriana da Expressão Gênica/fisiologia , Macrófagos/microbiologia , Proteínas Repressoras/metabolismo , Streptococcus agalactiae/genética , Streptococcus agalactiae/fisiologia , Animais , Cápsulas Bacterianas , Proteínas de Bactérias/genética , Linhagem Celular , Proteínas Hemolisinas/genética , Proteínas Hemolisinas/metabolismo , Histidina Quinase , Peptídeos e Proteínas de Sinalização Intracelular/genética , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Macrófagos/fisiologia , Camundongos , Perforina/genética , Perforina/metabolismo , Fagossomos , Pigmentos Biológicos , Espécies Reativas de Oxigênio , Proteínas Repressoras/genética , Fatores de Virulência/genética , Fatores de Virulência/metabolismoRESUMO
Globally, an estimated 36.7 million people were living with HIV (PLWH) and of these, 2.1 million were newly infected and 1.1 million died of AIDS in 2015. By 2016, only 67% of adults eligible for ART were enrolled in ART in Uganda. Delayed ART initiation has been shown to contribute to the continued transmission of HIV as well as to higher morbidity and mortality among persons living with HIV. Our study examined the prevalence and factors associated with delayed ART initiation among adults with HIV in Alebtong district, Northern Uganda. A cross-sectional study involving 432 adults living with HIV was conducted between March and June 2018 in Alebtong district. Quantitative data were collected using interviewer-administered questionnaires and desk reviews using a data extraction tool. A binary logistic regression using a hierarchical modelling technique was used at the multivariable level to determine associations at a 95% confidence interval and p<0.05 using SPSS Statistics software version 23.0. Overall, 432 participants were enrolled in the study, of whom 18.1% (78/432) had delayed ART initiation. After final adjustment, our key findings showed a significantly lower odds of delayed ART initiation among older respondents (aOR = 0.35, 95% CI: 0.16-0.76); adherence to HIV clinic appointments, (aOR = 0.06, 95% CI: 0.02-0.15); and linkage to the HIV clinic the same day HIV test was conducted (aOR = 0.21, 95% CI: 0.08-0.55). However, a significantly higher odds of delayed ART initiation was observed among those whose cultures do not support the use of ART (aOR = 10.62, 95% CI: 3.04-32.08). Reducing delayed ART initiation in the district requires strengthening the involvement of adolescents and young people in the HIVAIDS programming, scaling up the implementation of the same-day ART initiation policy, and addressing negative cultural beliefs affecting early ART initiation in the district.