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1.
Artigo em Inglês | MEDLINE | ID: mdl-39024537

RESUMO

Chronic alcohol consumption disrupts lung immunity and host defense mechanisms, rendering individuals with alcohol use disorder more susceptible to developing inflammatory lung conditions with poor prognoses. Here, we focused on investigating the molecular and cellular effects of alcohol ingestion on lung immunity in male and female subjects using population-based human lung transcriptomics analysis and an experimental mouse model of chronic alcohol drinking using the NIAAA alcohol feeding model. Flow cytometry and transcriptomics analyses in lungs revealed a sexually dimorphic effect of chronic alcohol drinking on lung immunity of both human and mouse. The male lungs were more sensitive to chronic alcohol drinking-induced dysregulation of lung immunity compared to the females. Furthermore, comparative transcriptomics analysis using lungs and liver samples from matched human and mouse subjects exhibited that lungs were more sensitive than the liver to the effects of alcohol in down-regulating immune-related genes and pathways. Furthermore, the transcriptomics analysis provided evidence that immunometabolic change is a central driver in lung alteration by downregulating the immune pathways and upregulating metabolic pathways. Chronic alcohol consumption resulted in reduced mTOR signaling and decreased immune cell populations. mTOR signaling axis may serve as an upstream regulator of alcohol-induced dysregulation in lung immunity.

2.
Public Health Action ; 14(2): 51-55, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38957505

RESUMO

The occurrence of transient culture positivity for Mycobacterium tuberculosis (MTB), known as mirage de tuberculose, poses significant challenges in understanding its spectrum and implications. Here, we report a case of transient culture positivity, oscillating between detectable and non-detectable MTB cultures with minimal radiological features and review the literature on this phenomenon. The scarcity of scientific literature on this subject stems from the inherent impossibility of systematically studying mirage de tuberculose. Ethical and public health concerns prevent withholding treatment to monitor spontaneous reversion to negative cultures. Based on the literature, we estimate that mirage de tuberculose occurs in approximately one-third of individuals infected with MTB who exhibit no symptoms. Despite the inherently limited nature of these findings, they suggest that the significance of mirage de tuberculose may be greater than currently perceived. Managing cases of mirage de tuberculose presents formidable challenges from a public health perspective. Striking a balance between prompt treatment initiation to prevent transmission and the risk of unnecessary treatment requires careful consideration. In conclusion, mirage de tuberculose remains a poorly understood clinical entity with very limited literature available. Advancing research and interdisciplinary collaborations are essential to unravel the intricacies of this phenomenon and develop effective strategies to address its public health challenges.


L'apparition d'une culture transitoire positive pour Mycobacterium tuberculosis (MTB), connue sous le nom de mirage de tuberculose, pose des défis importants dans la compréhension de son spectre et de ses implications. Nous rapportons ici un cas de positivité transitoire des cultures, oscillant entre des cultures MTB détectables et non détectables avec des caractéristiques radiologiques minimales et passons en revue la littérature sur ce phénomène. La rareté de la littérature scientifique sur ce sujet provient de l'impossibilité inhérente d'étudier systématiquement le mirage de tuberculose. Des préoccupations éthiques et de santé publique empêchent l'interruption du traitement pour surveiller le retour spontané à des cultures négatives. Sur la base de la littérature, nous estimons que le mirage de tuberculose survient chez environ un tiers des personnes infectées par le MTB qui ne présentent aucun symptôme. Malgré la nature intrinsèquement limitée de ces résultats, ils suggèrent que l'importance du mirage de tuberculose pourrait être plus grande que ce que l'on perçoit actuellement. La prise en charge des mirages de tuberculose présente des défis considérables du point de vue de la santé publique. Il faut trouver un équilibre entre l'instauration rapide du traitement pour prévenir la transmission et le risque d'un traitement inutile. En conclusion, le mirage de tuberculose reste une entité clinique mal comprise et la littérature disponible est très limitée. L'avancement de la recherche et les collaborations interdisciplinaires sont essentiels pour démêler les subtilités de ce phénomène et élaborer des stratégies efficaces pour relever ses défis en matière de santé publique.

3.
Viruses ; 15(7)2023 07 18.
Artigo em Inglês | MEDLINE | ID: mdl-37515256

RESUMO

Herpes simplex virus 2 (HSV-2) causes most sexually transmitted genital ulcerative disease. No effective prophylactic vaccine is currently available. Replication-defective (ICP8-) HSV stimulates immune responses in animals without producing progeny virus, making it potentially useful as a safe form of a live vaccine against HSV. We previously demonstrated that mice generate a stronger response to ICP8- virus encoding B7-2 costimulation molecules than to the parental replication-defective virus. We have also demonstrated enhanced immunogenicity of an ICP8-, virion host shutoff (vhs)- virus which can no longer destabilize viral and host mRNAs. Here, we constructed a triple mutant, ICP8-vhs-B7-2+ strain, and compared it to both double mutant viruses. Immunization of mice with a single dose of ICP8-B7-2+ or ICP8-vhs-B7-2+ virus decreased challenge virus replication in the vaginal mucosa, genital disease, and mortality more effectively than immunization with the ICP8-vhs- virus. Immunization with ICP8-B7-2+ or ICP8-vhs-B7-2+ virus also effectively suppressed subsequent HSV-2 infection of the nervous system compared to immunization with the ICP8-vhs- virus. ICP8-B7-2+ and ICP8-vhs-B7-2+ strains induced more IFN gamma-producing CD8 T cells and memory CD8 T cells than did ICP8-vhs- virus, potentially explaining the enhanced protective effects. Thus, B7 costimulation molecules expressed from a replication-defective vaccine can enhance vaccine efficacy, even in an immunocompetent host.


Assuntos
Herpes Simples , Herpesvirus Humano 2 , Feminino , Camundongos , Animais , Herpesvirus Humano 2/fisiologia , Antígenos B7 , Proteínas Virais , Replicação Viral , Vacinas Atenuadas , Vírion
4.
Adv Sci (Weinh) ; 10(16): e2207454, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37038090

RESUMO

Pulmonary fibrosis (PF) is a heterogeneous disease with a poor prognosis. Therefore, identifying additional therapeutic modalities is required to improve outcome. However, the lack of biomarkers of disease progression hampers the preclinical to clinical translational process. Here, this work assesses and identifies progressive alterations in pulmonary function, transcriptomics, and metabolomics in the mouse lung at 7, 14, 21, and 28 days after a single dose of oropharyngeal bleomycin. By integrating multi-omics data, this work identifies two central gene subnetworks associated with multiple critical pathological changes in transcriptomics and metabolomics as well as pulmonary function. This work presents a multi-omics-based framework to establish a translational link between the bleomycin-induced PF model in mice and human idiopathic pulmonary fibrosis to identify druggable targets and test therapeutic candidates. This work also indicates peripheral cannabinoid receptor 1 (CB1 R) antagonism as a rational therapeutic target for clinical translation in PF. Mouse Lung Fibrosis Atlas can be accessed freely at https://niaaa.nih.gov/mouselungfibrosisatlas.


Assuntos
Fibrose Pulmonar Idiopática , Multiômica , Humanos , Camundongos , Animais , Pulmão/patologia , Fibrose Pulmonar Idiopática/genética , Fibrose Pulmonar Idiopática/patologia , Bleomicina , Metabolômica
5.
Front Physiol ; 13: 860449, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35685280

RESUMO

Heavy alcohol drinking has negative health effects in multiple organs. It predisposes lungs to inflammatory conditions associated with acute lung injury and increased incidence of pneumonia and sepsis, which may lead to death due to acute respiratory distress syndrome in some individuals with alcohol use disorder (AUD). In general, rodent models of alcohol exposure either do not recapitulate multiple organ injuries as seen in humans or require longer duration to establish tissue injury and inflammation. The recently introduced NIAAA model of alcohol-induced liver injury, characterized by a marked increase in steatosis and liver damage with 10 days of a liquid diet containing 5% ethanol followed by a single ethanol binge (5 g/kg). Therefore, we employed this model to explore the status of surfactant phospholipids, oxidative stress, tissue injury markers and inflammatory cytokines in lungs. In lungs of C57BL/6J mice, the alcohol feeding significantly increased levels of the surfactant phospholipid dipalmitoyl phosphatidylcholine (DPPC) as well as the truncated oxidized phosphatidylcholines palmitoyl oxovaleryl phosphatidyl-choline (POVPC), palmitoyl glutaryl phosphatidyl-choline (PGPC), palmitoyl oxo-nonanoyl phosphatidyl-choline (ALDO-PC), and palmitoyl azelaoyl phosphatidyl-choline (PAzePC) at 9 h post-binge. Additionally, gene expression of the enzymes catalyzing lipid oxidation, such as arachidonate 15-lipoxygenase (Alox15), prostaglandin synthase 2 (Ptgs2), Cytochrome P450 2E1 (Cyp2E1) and NADPH oxidase 1 (Nox1) were significantly increased. Furthermore, ethanol increased levels of the inflammatory cytokine Interleukin-17 in bronchoalveolar lavage fluid. In conclusion, the NIAAA alcohol feeding model might be suitable to study alcohol-induced lung injury and inflammation.

6.
Sci Total Environ ; 838(Pt 1): 155790, 2022 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-35550890

RESUMO

The temporal evolution of molecular compositions and changes in structural features of Hillsboro Canal (Florida, USA) dissolved organic matter (DOM) was studied with an emphasis on nitrogen and sulfur containing molecules, after a 13 day time-series exposure to simulated sunlight. The Hillsboro Canal drains from the ridge and slough wetland environment underlain by peat soils from the northern extent of the Greater Everglades Ecosystem. The Hillsboro Canal-DOM was characterized by combining ultrahigh-resolution mass spectrometry (FT-ICR-MS), high-field nuclear magnetic resonance spectroscopy (1H NMR), size exclusion chromatography (SEC) with UV detection, and ultraviolet/visible (UV/vis) absorbance and excitation emission matrix (EEM) fluorescence spectroscopy. Size exclusion chromatography (SEC) demonstrated progressive depletion of higher mass molecules and a concomitant decrease of absorbance during photo-irradiation. NMR and FT-ICR-MS revealed nonlinear temporal evolution of DOM. In fact, FT-ICR-MS showed an initial depletion of supposedly chromophoric molecules often carrying major unsaturation accompanied by an uneven evolution of numbers of CHO, CHOS and CHNO compounds. While CHNO compounds continually increased throughout the entire photo-exposure time, CHO and CHOS compounds temporarily increased but declined after further light exposure. Progressive loss of highly unsaturated compounds was accompanied by production of low mass CHO and CHNO compounds with high O/C ratios. Area-normalized 1H NMR spectra of DOM in water and of the water insoluble fraction (~5%) in methanol revealed clear distinctions between irradiated and non-irradiated samples and congruent evolution of DOM structural features during irradiation, with more uniform trends in methanolic-DOM. Photoirradiation caused initial photoproduction of oxygenated aliphatic compounds, continued depletion of phenols and oxygenated aromatics, substantial change from initial natural product derived olefins to photoproduced olefins, and uneven evolution of carboxylated and alkylated benzene derivatives. This study demonstrates longer-term heteroatom-dependent photochemistry of DOM, which will affect the speciation of N and S heteroatoms, their connections to inorganic nutrients, and potentially their bioavailability.


Assuntos
Solo , Alcenos , Matéria Orgânica Dissolvida , Ecossistema , Água
7.
PNAS Nexus ; 1(3): pgac115, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-36741468

RESUMO

Fire is an integral component of ecosystems globally and a tool that humans have harnessed for millennia. Altered fire regimes are a fundamental cause and consequence of global change, impacting people and the biophysical systems on which they depend. As part of the newly emerging Anthropocene, marked by human-caused climate change and radical changes to ecosystems, fire danger is increasing, and fires are having increasingly devastating impacts on human health, infrastructure, and ecosystem services. Increasing fire danger is a vexing problem that requires deep transdisciplinary, trans-sector, and inclusive partnerships to address. Here, we outline barriers and opportunities in the next generation of fire science and provide guidance for investment in future research. We synthesize insights needed to better address the long-standing challenges of innovation across disciplines to (i) promote coordinated research efforts; (ii) embrace different ways of knowing and knowledge generation; (iii) promote exploration of fundamental science; (iv) capitalize on the "firehose" of data for societal benefit; and (v) integrate human and natural systems into models across multiple scales. Fire science is thus at a critical transitional moment. We need to shift from observation and modeled representations of varying components of climate, people, vegetation, and fire to more integrative and predictive approaches that support pathways toward mitigating and adapting to our increasingly flammable world, including the utilization of fire for human safety and benefit. Only through overcoming institutional silos and accessing knowledge across diverse communities can we effectively undertake research that improves outcomes in our more fiery future.

8.
J Hosp Infect ; 2020 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-32151675

RESUMO

OBJECTIVE: The international outbreak of cardiac surgery-associated Mycobacterium chimaera infections was traced back to infectious aerosols originating from contaminated water reservoirs of heater-cooler devices (HCD). In general, nontuberculous mycobacteria (NTM) frequently colonize water systems and can contaminate medical devices. Data on detection of NTM other than M. chimaera in samples gathered from HCDs are scarce. The present study summarizes prospective mycobacterial surveillance of five HCDs over more than four years. METHODS: A cohort of five, in 2014 factory-new acquired, LivaNova 3T (London, UK) HCDs were prospectively followed. Until mid-April 2014 HCDs were maintained according to the manufacturer's recommendations, subsequently according to an intensified in-house protocol including exhaust air evacuation. Mycobacterial surveillance cultures consisted of monthly water samples gathered from patient and cardioplegia circuits, as well as airflow samples. RESULTS: Out of 441 water samples, 170 (38.6%) revealed NTM growth. The most frequently detected NTM were Mycobacterium chimaera (n=120 (67.4%)), Mycobacterium gordonae (n=35 (19.7 %)), and Mycobacterium paragordonae (n=17 (9.6%)). Growth of NTM, M. chimaera and M. paragordonae was significantly more common in water samples derived from the patient than the cardioplegia circuit of the HCD. Three (2.0%) out of 150 air samples grew NTM. CONCLUSION: Growth of NTM in HCD water samples was frequent. Diverse NTM species were detected, with M. chimaera being most common. The majority of air samples remained negative. The relevance of NTM other than M. chimaera contaminating HCDs is poorly defined, but a recent report on a HCD-associated outbreak with Mycobacterium abscessus confirms a potential threat.

9.
Front Microbiol ; 10: 65, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30778338

RESUMO

Although cryoconite holes, sediment-filled melt holes on glacier surfaces, appear small and homogenous, their microbial inhabitants may be spatially partitioned. This partitioning could be particularly important for maintaining biodiversity in holes that remain isolated for many years, such as in Antarctica. We hypothesized that cryoconite holes with greater species richness and biomass should exhibit greater partitioning between the sediments and water, promoting greater biodiversity through spatial niche partitioning. We tested this hypothesis by sampling frozen cryoconite holes along a gradient of biomass and biodiversity in the Taylor Valley, Antarctica, where ice-lidded cryoconite holes are a ubiquitous feature of glaciers. We extracted DNA and chlorophyll a from the sediments and water of these samples to describe biodiversity and quantify proxies for biomass. Contrary to our expectation, we found that cryoconite holes with greater richness and biomass showed less partitioning of phylotypes by the sediments versus the water, perhaps indicating that the probability of sediment microbes being mixed into the water is higher from richer sediments. Another explanation may be that organisms from the water were compressed by freezing down to the sediment layer, leaving primarily relic DNA of dead cells to be detected higher in the frozen water. Further evidence of this explanation is that the dominant sequences unique to water closely matched organisms that do not live in cryoconite holes or the Dry Valleys (e.g., vertebrates); so this cryptic biodiversity could represent unknown microbial animals or DNA from atmospheric deposition of dead biomass in the otherwise low-biomass water. Although we cannot rule out spatial niche partitioning occurring at finer scales or in melted cryoconite holes, we found no evidence of partitioning between the sediments and water in frozen holes. Future work should include more sampling of cryoconite holes at a finer spatial scale, and characterizing the communities of the sediments and water when cryoconite holes are melted and active.

10.
Antiviral Res ; 156: 102-106, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-29908958

RESUMO

Herpes simplex virus (HSV)-1 and HSV-2 cause painful blisters and shallow ulcers in exposed skin and mucosae during primary or recurrent infection. In addition, recurrent and potentially blinding HSV-1 infections of the eye afflict nearly half a million persons in the U.S. Current clinical therapies rely on nucleoside analog drugs such as acyclovir (ACV) or ganciclovir to ameliorate primary infections and reduce the frequency and duration of reactivations. However, these treatments do not fully suppress viral shedding and drug-resistant mutants develop in the eye and in vulnerable, immunosuppressed patients. Herpesvirus DNA replication requires several enzymes in the nucleotidyl transferase superfamily (NTS) that have recombinase and nuclease activities. We previously found that compounds which block NTS enzymes efficiently inhibit replication of HSV-1 and HSV-2 by up to 1 million-fold in Vero and human foreskin fibroblasts. Among the compounds with potent suppressive effects in culture is the anti-fungal drug ciclopirox. Here we report that topical application of ciclopirox olamine to the eyes of mice infected with HSV-1 reduced virus shed from the corneal epithelium compared with saline control, and reduced development of blepharitis to the level of mice treated with ACV. Results were dose-dependent. In addition, treatment with ciclopirox olamine significantly reduced acute and latent HSV-1 infection of the peripheral nervous system. These results support further development of ciclopirox olamine as a repurposed topical agent for HSV infections.


Assuntos
Antivirais/administração & dosagem , Ciclopirox/administração & dosagem , Oftalmopatias/tratamento farmacológico , Herpes Simples/tratamento farmacológico , Herpesvirus Humano 1/efeitos dos fármacos , Replicação Viral/efeitos dos fármacos , Animais , Antivirais/farmacologia , Ciclopirox/farmacologia , Córnea/virologia , Modelos Animais de Doenças , Herpesvirus Humano 1/crescimento & desenvolvimento , Camundongos , Nucleotidiltransferases/antagonistas & inibidores , Resultado do Tratamento , Eliminação de Partículas Virais
11.
Environ Sci Technol ; 51(2): 771-779, 2017 01 17.
Artigo em Inglês | MEDLINE | ID: mdl-28032509

RESUMO

To characterize the effects of thermal-alteration on water extractable organic matter (WEOM), soil samples were heated in a laboratory at 225, 350, and 500 °C. Next, heated and unheated soils were leached, filtered, and analyzed for dissolved organic carbon (DOC) concentration, optical properties, molecular size distribution, molecular composition, and disinfection byproduct (DBP) formation following the addition of chlorine. The soils heated to 225 °C leached the greatest DOC and had the highest C- and N-DBP precursor reactivity per unit carbon compared to the unheated material or soils heated to 350 or 500 °C. The molecular weight of the soluble compounds decreased with increasing heating temperature. Compared to the unheated soil leachates, all DBP yields were higher for the leachates of soils heated to 225 °C. However, only haloacetonitrile yields (µg/mgC) were higher for leachates of the soils heated to 350 °C, whereas trihalomethane, haloacetic acid and chloropicrin yields were lower compared to unheated soil leachates. Soluble N-containing compounds comprised a high number of molecular formulas for leachates of heated soils, which may explain the higher yield of haloacetonitriles for heated soil leachates. Overall, heating soils altered the quantity, quality, and reactivity of the WEOM pool. These results may be useful for inferring how thermal alteration of soil by wildfire can affect water quality.


Assuntos
Desinfecção , Solo , Carbono/química , Trialometanos , Água
12.
Water Res ; 88: 981-989, 2016 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-26624231

RESUMO

Hardness and DOC removal in a single ion exchange unit operation allows for less infrastructure, is advantageous for process operation and depending on the water source, could enhance anion exchange resin removal of dissolved organic carbon (DOC). Simultaneous application of cationic (Plus) and anionic (MIEX) ion exchange resin in a single contact vessel was tested at pilot and bench scales, under multiple regeneration cycles. Hardness removal correlated with theoretical predictions; where measured hardness was between 88 and 98% of the predicted value. Comparing bench scale DOC removal of solely treating water with MIEX compared to Plus and MIEX treated water showed an enhanced DOC removal, where removal was increased from 0.5 to 1.25 mg/L for the simultaneous resin application compared to solely applying MIEX resin. A full scale MIEX treatment plant (14.5 MGD) reduced raw water DOC from 13.7 mg/L to 4.90 mg/L in the treated effluent at a bed volume (BV) treatment rate of 800, where a parallel operation of a simultaneous MIEX and Plus resin pilot (10 gpm) measured effluent DOC concentrations of no greater than 3.4 mg/L, even at bed volumes of treatment 37.5% greater than the full scale plant. MIEX effluent compared to simultaneous Plus and MIEX effluent resulted in differences in fluorescence intensity that correlated to decreases in DOC concentration. The simultaneous treatment of Plus and MIEX resin produced water with predominantly microbial character, indicating the enhanced DOC removal was principally due to increased removal of terrestrially derived organic matter. The addition of Plus resin to a process train with MIEX resin allows for one treatment process to remove both DOC and hardness, where a single brine waste stream can be sent to sewer at a full-scale plant, completely removing lime chemical addition and sludge waste disposal for precipitative softening processes.


Assuntos
Resinas de Troca Aniônica/química , Resinas de Troca de Cátion/química , Substâncias Húmicas/análise , Poluentes Químicos da Água/química , Purificação da Água/métodos , Florida
13.
Photochem Photobiol ; 91(3): 684-95, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25772776

RESUMO

In this study, we contrast the fluorescent properties of dissolved organic matter (DOM) in fens and bogs in a Northern Minnesota peatland using excitation emission matrix fluorescence spectroscopy with parallel factor analysis (EEM-PARAFAC). EEM-PARAFAC identified four humic-like components and one protein-like component and the dynamics of each were evaluated based on their distribution with depth as well as across sites differing in hydrology and major biological species. The PARAFAC-EEM experiments were supported by dissolved organic carbon measurements (DOC), optical spectroscopy (UV-Vis), and compositional characterization by ultrahigh resolution Fourier transform ion cyclotron resonance mass spectroscopy (FT-ICR MS). The FT-ICR MS data indicate that metabolism in peatlands reduces the molecular weights of individual components of DOM, and oxygen-rich less aromatic molecules are selectively biodegraded. Our data suggest that different hydrologic and biological conditions within the larger peat ecosystem drive molecular changes in DOM, resulting in distinctly different chemical compositions and unique fluorescent fingerprints. PARAFAC modeling of EEM data coupled with ultrahigh resolution FT-ICR MS has the potential to provide significant molecular-based information on DOM composition that will support efforts to better understand the composition, sources, and diagenetic status of DOM from different terrestrial and aquatic systems.

14.
J Phycol ; 49(3): 546-54, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-27007043

RESUMO

Several algal species responsible for harmful algal blooms (HABs), such as Alexandrium fundyense, are mixotrophic under certain environmental conditions. The ability to switch between photosynthetic and heterotrophic modes of growth may play a role in the development of HABs in coastal regions. We examined the influence of humic dissolved organic matter (HDOM) derived from terrestrial (plant/soil) and microbial sources on the growth of A. fundyense. We found that a terrestrially derived HDOM, Suwannee River humic acid (SRHA), did enhance A. fundyense growth; however, a microbially derived HDOM, Pony Lake fulvic acid (PLFA) did not enhance growth. A. fundyense grows in association with bacteria in culture and we observed that bacterial cell densities were much lower in A. fundyense cultures than in bacteria-only cultures, consistent with bacterial grazing by A. fundyense in culture. In bacteria-only cultures with added algal exudates (EX), the addition of PLFA and SRHA resulted in a slight increase in bacterial cell density compared to cultures without HDOM added. Changes over time in the chemical quality of the HDOM in the A. fundyense cultures reflected contributions of microbially derived material with similar characteristics as the PLFA. Overall, these results suggest that the chemical differences between SRHA and PLFA are responsible for the greater effect of SRHA on A. fundyense growth, and that the differential effect is not a result of an effect on the growth of associated bacteria.

15.
Proc Natl Acad Sci U S A ; 109(50): 20626-31, 2012 Dec 11.
Artigo em Inglês | MEDLINE | ID: mdl-23185006

RESUMO

The permanent ice cover of Lake Vida (Antarctica) encapsulates an extreme cryogenic brine ecosystem (-13 °C; salinity, 200). This aphotic ecosystem is anoxic and consists of a slightly acidic (pH 6.2) sodium chloride-dominated brine. Expeditions in 2005 and 2010 were conducted to investigate the biogeochemistry of Lake Vida's brine system. A phylogenetically diverse and metabolically active Bacteria dominated microbial assemblage was observed in the brine. These bacteria live under very high levels of reduced metals, ammonia, molecular hydrogen (H(2)), and dissolved organic carbon, as well as high concentrations of oxidized species of nitrogen (i.e., supersaturated nitrous oxide and ∼1 mmol⋅L(-1) nitrate) and sulfur (as sulfate). The existence of this system, with active biota, and a suite of reduced as well as oxidized compounds, is unusual given the millennial scale of its isolation from external sources of energy. The geochemistry of the brine suggests that abiotic brine-rock reactions may occur in this system and that the rich sources of dissolved electron acceptors prevent sulfate reduction and methanogenesis from being energetically favorable. The discovery of this ecosystem and the in situ biotic and abiotic processes occurring at low temperature provides a tractable system to study habitability of isolated terrestrial cryoenvironments (e.g., permafrost cryopegs and subglacial ecosystems), and is a potential analog for habitats on other icy worlds where water-rock reactions may cooccur with saline deposits and subsurface oceans.


Assuntos
Lagos/microbiologia , Microbiologia da Água , Regiões Antárticas , Bactérias/classificação , Bactérias/genética , Bactérias/isolamento & purificação , Clima Frio , Ecossistema , Evolução Molecular , Gelo , Lagos/análise , Microscopia Eletrônica de Varredura , Dados de Sequência Molecular , Filogenia , RNA Bacteriano/genética , RNA Ribossômico/genética
16.
Mar Pollut Bull ; 64(8): 1678-87, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22768803

RESUMO

Using fluorescence spectroscopy and parallel factor analysis (PARAFAC) we characterized and modeled the fluorescence properties of dissolved organic matter (DOM) in samples from the Penobscot River, Androscoggin River, Penobscot Bay, and the Gulf of Maine (GoM). We analyzed excitation-emission matrices (EEMs) using an existing PARAFAC model (Cory and McKnight, 2005) and created a system-specific model with seven components (GoM PARAFAC). The GoM PARAFAC model contained six components similar to those in other PARAFAC models and one unique component with a spectrum similar to a residual found using the Cory and McKnight (2005) model. The unique component was abundant in samples from the Androscoggin River immediately downstream of a pulp mill effluent release site. The detection of a PARAFAC component associated with an anthropogenic source of DOM, such as pulp mill effluent, demonstrates the importance for rigorously analyzing PARAFAC residuals and developing system-specific models.


Assuntos
Monitoramento Ambiental/métodos , Poluentes da Água/análise , Fluorescência , Maine , Modelos Químicos , Espectrometria de Fluorescência , Madeira/análise
17.
J Cardiopulm Rehabil ; 19(6): 366-72, 1999.
Artigo em Inglês | MEDLINE | ID: mdl-10609187

RESUMO

PURPOSE: The safety of one repetition maximum (1RM) testing for patients with chronic obstructive pulmonary disease (COPD) has not been determined. Therefore, this study was conducted to determine the prevalence of abnormal cardiopulmonary responses, muscle soreness, and muscle injury of patients with moderate to severe COPD in response to 1RM testing. METHODS: Twenty pulmonary rehabilitation patients (11 women and 9 men) with moderate or severe COPD participated in this investigation. The 1RM testing was performed using the parallel squat and incline press. Blood pressure, heart rate dyspnea ratings, and oxygen saturation responses were measured immediately following the 1RM procedure. Ratings of muscle soreness and injury were measured immediately after 1RM testing and on days 2 and 7. RESULTS: No injury, significant muscle soreness, or abnormal cardiopulmonary responses occurred as a result of 1RM testing. No gender differences were found for any variable measured in response to 1RM testing. CONCLUSIONS: A properly supervised and screened pulmonary rehabilitation population can be 1RM tested without significant muscle soreness, injury, or abnormal cardiopulmonary responses.


Assuntos
Terapia por Exercício/métodos , Pneumopatias Obstrutivas/reabilitação , Atividades Cotidianas , Idoso , Pressão Sanguínea , Feminino , Frequência Cardíaca , Humanos , Pneumopatias Obstrutivas/fisiopatologia , Masculino , Pessoa de Meia-Idade , Músculo Esquelético/patologia , Oxigênio/sangue
18.
Schweiz Med Wochenschr ; 123(5): 174-82, 1993 Feb 06.
Artigo em Alemão | MEDLINE | ID: mdl-8438140

RESUMO

In 1990, 1530 active Swiss athletes of national or international level (53% response rate) answered a questionnaire on allergies, hay fever and respiratory symptoms during or after physical effort. Compared with 1986, the prevalence of allergies among these athletes had increased from 14.7 to 18%, and of hay fever from 16.8 to 19.7%. The prevalence of respiratory symptoms was 12.1 in 1990, compared with 7.1% in 1986. Smoking was less frequent than in 1986 (7.1% against 12%). There was a significant correlation between the reported allergies and respiratory symptoms, but none between respiratory symptoms and smoking or frequency of consultations at a physician's office. The examination of 104 athletes complaining of respiratory symptoms on 10 minutes ergometry showed a decrease of FEV1 of 10% or more in 21%. Exercise induced asthma (EIA) is not as frequent as suspected in other publications. 25% of the sportsmen examined showed a cutaneous allergy to one or more of the six most frequent inhalative allergens. The typical history of dyspnea, wheezing or coughing after exercise, possibly combined with a feeling of tightness of the chest or the larynx, and the number of positive allergy skin test reactions, correlated with the decrease in FEV1 after exercise. A considerable percentage of these athletes do not treat their respiratory symptoms or ask for professional help. In medical treatment, attention must be paid to doping regulations. IOC accepts the use of salbutamol, terbutaline, orciprenaline and Cromoglycic acid in the treatment of asthma. Corticosteroids by inhalation are accepted but intramuscular injection is forbidden.(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Asma Induzida por Exercício/epidemiologia , Hipersensibilidade Respiratória/epidemiologia , Esportes , Adolescente , Adulto , Criança , Teste de Esforço , Feminino , Volume Expiratório Forçado , Humanos , Masculino , Pessoa de Meia-Idade , Hipersensibilidade Respiratória/diagnóstico , Rinite Alérgica Sazonal/epidemiologia , Testes Cutâneos , Fumar/efeitos adversos , Inquéritos e Questionários , Suíça/epidemiologia
19.
Am J Health Promot ; 7(2): 118-28, 1992.
Artigo em Inglês | MEDLINE | ID: mdl-10148716

RESUMO

PURPOSE OF THE REVIEW. The purpose of this review is to assist those who work in the field of health promotion when considering the implementation of an individually risk-rated health insurance plan. It does so by introducing the reader to the concept of individually risk-rating health insurance; uncritically reviewing selected risk-rated health insurance plans; and exploring several issues related to plan implementation, administration, and appropriateness. SEARCH METHODS USED. The review is based on the authors' awareness of the literature in the fields of preventive medicine, health promotion, and employee benefits. The six individually risk-rated health insurance programs that are reviewed were chosen because they demonstrate how aspects of the National Association of Insurance Commissioners' Model have been implemented using various combinations of administrative procedures, verification strategies, and types of economic incentives or disincentives. This review is not intended to be a comprehensive review of the literature. SUMMARY OF IMPORTANT FINDINGS. Individually risk-rated health insurance programs have been established using a variety of administrative procedures, verification strategies, and types of economic incentives or disincentives. The frequency with which these programs are being established is increasing. As the number of risk-rated programs grows, it will be increasingly important to address the many issues that implementing such plans generate: How should lifestyle behaviors be verified? Will healthy lifestyles save money? Can employees fully control their risk factors? Is risk-rating socially responsible? MAJOR CONCLUSIONS. As risk-rating becomes more widespread, there will be a continuing need to address the business, medical, ethical, and legal issues these programs create and to refine them accordingly. The health promotion community has both an opportunity and obligation to see to it that individually risk-rated health insurance programs are implemented in a socially acceptable manner and that the outcomes they generate are cost-beneficial.


Assuntos
Planos para Motivação de Pessoal/organização & administração , Comportamentos Relacionados com a Saúde , Planos de Assistência de Saúde para Empregados/organização & administração , Custos de Cuidados de Saúde , Promoção da Saúde/organização & administração , Benefícios do Seguro , Saúde Ocupacional , Planos para Motivação de Pessoal/economia , Feminino , Planos de Assistência de Saúde para Empregados/economia , Promoção da Saúde/economia , Humanos , Benefícios do Seguro/economia , Estilo de Vida , Masculino , Avaliação de Programas e Projetos de Saúde , Fatores de Risco , Estados Unidos
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