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1.
Prim Health Care Res Dev ; 20: e91, 2019 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-32799970

RESUMO

AIMS: The primary objective of this study was to evaluate feasibility and acceptability of Mindfulness-based Wellness and Resilience (MBWR): a brief mindfulness-based intervention designed to enhance resilience and is delivered to interdisciplinary primary care teams. BACKGROUND: Burnout is a pervasive, international problem affecting the healthcare workforce, characterized by emotional exhaustion, depersonalization, and decreased professional effectiveness. Delivery models of mindfulness-based resilience interventions that enhance feasibility for onsite delivery, consider cultural considerations specific to primary care, and utilize team processes that are integral to primary care are now needed. METHODS: We conducted a mixed-methods feasibility and acceptability trial of MBWR. Primary feasibility and acceptability outcomes were assessed by number of participants recruited, percent of MBWR treatment completer, and attrition rate during the 8-week intervention, and four items on a Likert-type scale. Secondary outcomes of perceived effects were measured by focus groups, an online survey, and self-reported questionnaires, including the Brief Resilience Scale, the Five Facet Mindfulness Questionnaire-Short Form, and the Self-Compassion Scale-Short Form. Participants included 31 healthcare providers on interdisciplinary primary care teams employed a safety-net medical center. In the MBWR group, 68% identified as Latinx, compared to 64% in the control group. FINDINGS: All criteria for feasibility were met and participants endorsed high levels of satisfaction and acceptability. The results of this study suggest that MBWR provides multiple perceived benefits to the individual healthcare provider, cohesion of the healthcare team, and enhanced patient care. MBWR may be a feasible and acceptable method to integrate mindfulness, resilience, and teamwork training into the primary care setting.


Assuntos
Esgotamento Profissional/prevenção & controle , Pessoal de Saúde/psicologia , Atenção Plena/métodos , Atenção Primária à Saúde , Avaliação de Programas e Projetos de Saúde/métodos , Resiliência Psicológica , Esgotamento Profissional/psicologia , Estudos de Viabilidade , Feminino , Humanos , Masculino , Inquéritos e Questionários
2.
J Emerg Med ; 53(1): 18-29, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28343797

RESUMO

BACKGROUND: Identifying patients who may progress to a poor clinical outcome will encourage earlier appropriate therapeutic interventions. Brain edema may contribute to secondary injury in traumatic brain injury (TBI) and thus, may be a useful prognostic indicator. OBJECTIVE: We determined whether the presence of brain edema on the initial computed tomography (CT) scan of TBI patients would predict poor in-hospital outcome. METHODS: We performed a retrospective review of all trauma patients with nonpenetrating head trauma at a Level I Trauma Center. International Classification of Diseases, Ninth Revision codes indicated the presence of brain edema and we evaluated the validity of this pragmatic assessment quantitatively in a random subset of patients. In-hospital mortality was the primary outcome variable. Univariate analysis and logistic regression identified predictors of mortality in all TBI patients and those with mild TBI. RESULTS: Over 7200 patients were included in the study, including 6225 with mild TBI. Measurements of gray and white matter CT density verified radiological assessments of brain edema. Patients with documented brain edema had a mortality rate over 10 times that of the entire study population. With logistic regression accounting for Injury Severity Score, Glasgow Coma Scale score, other CT findings, and clinical variables, brain edema predicted an eightfold greater mortality rate in all patients (odds ratio 8.0, 95% confidence interval 4.6-14.0) and fivefold greater mortality rate for mild TBI patients (odds ratio 4.9, 95% confidence interval 2.0-11.7). CONCLUSIONS: Brain edema is an independent prognostic variable across all categories of TBI severity. By alerting emergency physicians to patients with poor predicted clinical outcomes, this finding will drive better resource allocation, earlier intervention, and reduced patient mortality.


Assuntos
Edema Encefálico/complicações , Lesões Encefálicas Traumáticas/mortalidade , Mortalidade Hospitalar , Prognóstico , Fatores de Tempo , Adulto , Edema Encefálico/mortalidade , Serviço Hospitalar de Emergência/organização & administração , Feminino , Escala de Coma de Glasgow , Humanos , Escala de Gravidade do Ferimento , Tempo de Internação , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Ohio , Estudos Retrospectivos , Tomografia Computadorizada por Raios X/métodos
3.
Ecol Appl ; 24(2): 385-95, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24689149

RESUMO

The conservation of species at risk of extinction requires data to support decisions at landscape to regional scales. There is a need for information that can assist with locating suitable habitats in fragmented and degraded landscapes to aid the reintroduction of at-risk plant species. In addition, desiccation and water stress can be significant barriers to the success of at-risk plant reintroduction programs. We examine how airborne light detection and ranging (LiDAR) data can be used to model microtopographic features that reduce water stress and increase resource availability, providing information for landscape planning that can increase the success of reintroduction efforts for a dryland landscape in Hawaii. We developed a topographic habitat-suitability model (HSM) from LiDAR data that identifies topographic depressions that are protected from prevailing winds (high-suitability sites) and contrasts them with ridges and other exposed areas (low-suitability sites). We tested in the field whether high-suitability sites had microclimatic conditions that indicated better-quality habitat compared to low-suitability sites, whether plant-response traits indicated better growing conditions in high-suitability sites, whether the locations of individuals of existing at-risk plant species corresponded with our habitat-suitability classes, and whether the survival of planted individuals of a common native species was greater in high-suitability, compared to low-suitability, planting sites. Mean wind speed in a high-suitability field site was over five times lower than in a low-suitability site, and soil moisture and leaf wetness were greater, indicating less stress and greater resource availability in high-suitability areas. Plant height and leaf nutrient content were greater in high-suitability areas. Six at-risk species showed associations with high-suitability areas. The survival of planted individuals was less variable among high-suitability plots. These results suggest that plant establishment and survival is associated with the habitat conditions identified by our model. The HSM can improve the survival of planted individuals, reduce the cost of restoration and reintroduction programs through targeted management activities in high-suitability areas, and expand the ability of managers to make landscape-scale decisions regarding land-use, land acquisition, and species recovery.


Assuntos
Ecossistema , Espécies em Perigo de Extinção , Plantas/classificação , Clima , Havaí , Fatores de Tempo
4.
J Am Coll Surg ; 218(4): 734-8, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24508425

RESUMO

BACKGROUND: The influence of in-house (IH) attendings on trauma patient survival and efficiency measures, such as emergency department length of stay (LOS), ICU LOS, and hospital LOS, has been debated for more than 20 years. No study has definitively shown improved outcomes with IH vs home-call attendings. This study examines trauma outcomes in a single, Level I trauma center before and after the institution of IH attending call. STUDY DESIGN: Patient data were collected from the University of Kentucky's trauma registry. Based on the Trauma-Related Injury Severity Score, survival rates were compared between the IH and home-call groups. To evaluate efficiency, emergency department LOS, ICU LOS, and hospital LOS were compared. A separate subanalysis for the most severely injured patients (trauma alert red) was also performed. RESULTS: The home-call group (n = 4,804) was younger (p = 0.018) and had a higher Injury Severity Score (p = 0.003) than the IH group (n = 5259), but there was no difference in Trauma-Related Injury Severity Score (p = 0.205) between groups. In-house attending presence did not reduce mortality. Emergency department LOS, ICU LOS, and hospital LOS were shorter during the IH period. Emergency department to operating room time was not different. There was no change in trauma alert red mortality with an attending present (20.7% vs 18.2%, p = 0.198). CONCLUSIONS: In-house attending presence does not improve trauma patient survival. For the most severely injured patients, attendings presence does not reduce mortality. In-house coverage can improve hospital efficiency by decreasing emergency department LOS, hospital LOS, and ICU LOS.


Assuntos
Serviço Hospitalar de Emergência/organização & administração , Mortalidade Hospitalar , Médicos Hospitalares , Tempo de Internação/estatística & dados numéricos , Ferimentos e Lesões/terapia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Eficiência Organizacional , Serviço Hospitalar de Emergência/estatística & dados numéricos , Feminino , Humanos , Escala de Gravidade do Ferimento , Kentucky , Modelos Lineares , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Avaliação de Processos e Resultados em Cuidados de Saúde , Sistema de Registros , Estudos Retrospectivos , Taxa de Sobrevida , Fatores de Tempo , Centros de Traumatologia , Ferimentos e Lesões/mortalidade , Adulto Jovem
6.
J Trauma Acute Care Surg ; 73(5 Suppl 4): S301-6, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23114485

RESUMO

BACKGROUND: Diagnosing blunt cardiac injury (BCI) can be difficult. Many patients with mechanism for BCI are admitted to the critical care setting based on associated injuries; however, debate surrounds those patients who are hemodynamically stable and do not otherwise require a higher level of care. To allow safe discharge home or admission to a nonmonitored setting, BCI should be definitively ruled out in those at risk. METHODS: This Eastern Association for the Surgery of Trauma (EAST) practice management guideline (PMG) updates the original from 1998. English-language citations were queried for BCI from March 1997 through December 2011, using the PubMed Entrez interface. Of 599 articles identified, prospective or retrospective studies examining BCI were selected. Each article was reviewed by two members of the EAST BCI PMG workgroup. Data were collated, and a consensus was obtained for the recommendations. RESULTS: We identified 35 institutional studies evaluating the diagnosis of adult patients with suspected BCI. This PMG has 10 total recommendations, including two Level 2 updates, two upgrades from Level 3 to Level 2, and three new recommendations. CONCLUSION: Electrocardiogram (ECG) alone is not sufficient to rule out BCI. Based on four studies showing that the addition of troponin I to ECG improved the negative predictive value to 100%, we recommend obtaining an admission ECG and troponin I from all patients in whom BCI is suspected. BCI can be ruled out only if both ECG result and troponin I level are normal, a significant change from the previous guideline. Patients with new ECG changes and/or elevated troponin I should be admitted for monitoring. Echocardiogram is not beneficial as a screening tool for BCI and should be reserved for patients with hypotension and/or arrhythmias. The presence of a sternal fracture alone does not predict BCI. Cardiac computed tomography or magnetic resonance imaging can be used to differentiate acute myocardial infarction from BCI in trauma patients.


Assuntos
Traumatismos Cardíacos/diagnóstico , Ferimentos não Penetrantes/diagnóstico , Eletrocardiografia , Traumatismos Cardíacos/diagnóstico por imagem , Traumatismos Cardíacos/fisiopatologia , Humanos , Imageamento por Ressonância Magnética , Tomografia Computadorizada por Raios X , Troponina I/sangue , Ferimentos não Penetrantes/diagnóstico por imagem , Ferimentos não Penetrantes/fisiopatologia
7.
J Trauma Acute Care Surg ; 73(5 Suppl 4): S307-14, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23114486

RESUMO

BACKGROUND: An estimated 1.1 million people sustain a mild traumatic brain injury (MTBI) annually in the United States. The natural history of MTBI remains poorly characterized, and its optimal clinical management is unclear. The Eastern Association for the Surgery of Trauma had previously published a set of practice management guidelines for MTBI in 2001. The purpose of this review was to update these guidelines to reflect the literature published since that time. METHODS: The PubMed and Cochrane Library databases were searched for articles related to MTBI published between 1998 and 2011. Selected older references were also examined. RESULTS: A total of 112 articles were reviewed and used to construct a series of recommendations. CONCLUSION: The previous recommendation that brain computed tomographic (CT) should be performed on patients that present acutely with suspected brain trauma remains unchanged. A number of additional recommendations were added. Standardized criteria that may be used to determine which patients receive a brain CT in resource-limited environments are described. Patients with an MTBI and negative brain CT result may be discharged from the emergency department if they have no other injuries or issues requiring admission. Patients taking warfarin who present with an MTBI should have their international normalized ratio (INR) level determined, and those with supratherapeutic INR values should be admitted for observation. Deficits in cognition and memory usually resolve within 1 month but may persist for longer periods in 20% to 40% of cases. Routine use of magnetic resonance imaging, positron emission tomography, nuclear magnetic resonance, or biochemical markers for the clinical management of MTBI is not supported at the present time.


Assuntos
Lesões Encefálicas/diagnóstico , Lesões Encefálicas/terapia , Encéfalo/diagnóstico por imagem , Lesões Encefálicas/diagnóstico por imagem , Serviço Hospitalar de Emergência/normas , Humanos , Coeficiente Internacional Normatizado , Alta do Paciente/normas , Tomografia Computadorizada por Raios X
8.
J Biomed Sci ; 17 Suppl 1: S10, 2010 Aug 24.
Artigo em Inglês | MEDLINE | ID: mdl-20804584

RESUMO

BACKGROUND: Hippocampal slices swell and release taurine during oxidative stress. The influence of cellular signalling pathways on this process is unclear. Glutamate signalling can facilitate volume regulation in other CNS preparations. Therefore, we hypothesize activation of taurine release by oxidative stress results from tissue swelling and is coupled to activation of glutamate receptors. METHODS: Rat hippocampi were incubated at room temperature for 2 hr in artificial cerebrospinal fluid (aCSF) equilibrated with 95% O2 plus 5% CO2. For some slices, 1 mM taurine was added to the aCSF to maintain normal tissue taurine content. Slices then were perfused with aCSF at 35 degrees C and baseline data recorded before 2 mM H2O2 was added. For some studies, mannitol or inhibitors of glutamate receptors or the volume-regulated anion channel (VRAC) were added before and during H2O2 treatment. The intensity of light transmitted through the slice (the intrinsic optical signal, IOS) was determined at 1-min intervals. Samples of perfusate were collected at 2-min intervals and amino acid contents determined by HPLC. Data were analyzed by repeated measures ANOVA and post hoc Dunnett's test with significance indicated for p<0.05. RESULTS: IOS of slices prepared without taurine treatment increased significantly by 3.3+/-1.3% (mean+/-SEM) during oxidative stress. Little taurine was detected in the perfusate of these slices and the rate of taurine efflux did not change during H2O2 exposure. The alpha-amino-3-hydroxyl-5-methyl-4-isoxazole-propionate antagonist, 25 microM CNQX, but not the N-methyl-D-aspartate (NMDA) receptor antagonist, 10 microM MK-801, inhibited the increase in IOS during H2O2 treatment. Taurine-treated slices exposed to H2O2 showed no change in IOS; however, taurine efflux increased by 335+/-178%. When these slices were perfused with hypertonic aCSF (350 mOsm) or exposed to the VRAC inhibitor, 20 microM DCPIB, no increase in the taurine efflux rate was observed during H2O2 exposure. Taurine-treated slices perfused with 10 microM MK-801 during H2O2 exposure showed a 4.6+/-1.9% increase in IOS but no increase in the taurine efflux rate. CONCLUSIONS: Taurine efflux via VRAC is critical for volume regulation of hippocampal slices exposed to oxidative stress. This increased taurine efflux does not result from direct activation of the taurine release pathway by H2O2. NMDA receptor activation plays an important role in taurine release during oxidative stress.


Assuntos
Hipocampo/metabolismo , Estresse Oxidativo , Receptores de Glutamato/metabolismo , Taurina/metabolismo , Animais , Hipocampo/efeitos dos fármacos , Peróxido de Hidrogênio/farmacologia , Masculino , Oxidantes/farmacologia , Ratos , Ratos Sprague-Dawley
9.
J Trauma ; 67(2): 389-402, 2009 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-19667896

RESUMO

Although the need and benefit of prehospital interventions has been controversial for quite some time, an increasing amount of evidence has stirred both sides into more frequent debate. Proponents of the traditional "scoop-and-run" technique argue that this approach allows a more timely transfer to definitive care facilities and limits unnecessary (and potentially harmful) procedures. However, advocates of the "stay-and-play" method point to improvement in survival to reach the hospital and better neurologic outcomes after brain injury. Given the lack of consensus, the Eastern Association for the Surgery of Trauma convened a Practice Management Guideline committee to answer the following questions regarding prehospital resuscitation: (1) should injured patients have vascular access attempted in the prehospital setting? (2) if so, what location is preferred for access? (3) if access is achieved, should intravenous fluids be administered? (4) if fluids are to be administered, which solution is preferred? and (5) if fluids are to be administered, what volume and rate should be infused?


Assuntos
Serviços Médicos de Emergência/métodos , Hidratação/métodos , Ferimentos e Lesões/terapia , Humanos
10.
Ann Pharmacother ; 43(2): 210-9, 2009 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19193593

RESUMO

BACKGROUND: Catheter-related bloodstream infections (CRBSIs) are a primary concern in patients with indwelling central venous catheters (CVCs). Instillation of an antibiotic lock solution may serve as an adjunctive therapy. OBJECTIVE: To evaluate the efficacy of novel antibiotic-anticoagulant lock solutions using an in vitro model of CVC infection. METHODS: The following lock solutions were evaluated: daptomycin 1 mg/mL (reconstituted with lactated Ringer's [LR]) plus heparin 5000 units/mL, tigecycline 0.5 mg/mL plus ethylenediaminetetraacetate (EDTA) 30 mg/mL, gentamicin 5 mg/mL plus EDTA 30 mg/mL, cefazolin 5 mg/mL plus heparin 5000 units/mL, and phosphate-buffered NaCl 0.9% as the control solution. Analysis was performed on Hickman catheter segments inoculated with the following organisms: methicillin-sensitive Staphylococcus aureus, methicillin-resistant S. aureus (MRSA), Staphylococcus epidermidis, and Pseudomonas aeruginosa. The catheters were incubated in the candidate lock solutions for 0, 2, 4, and 24 hours. Student's t-tests were conducted to evaluate reduction in log(10) colony-forming units/milliliter (cfu/mL) of individual lock solutions compared with the control solution. For each organism, analysis of variance and Student's t-tests were performed to determine whether differences existed among the lock solutions. RESULTS: Gentamicin plus EDTA (G+EDTA) and tigecycline plus EDTA (Ti+EDTA) resulted in significant reductions (p < 0.05) of log(10) cfu/mL at 24 hours for all organisms tested. Daptomycin, reconstituted in LR, plus heparin (D+LR+H) demonstrated potent activity against all staphylococcal species (p < 0.05). With respect to MRSA, G+EDTA displayed significantly better activity than Ti+EDTA and cefazolin plus heparin (p < 0.05), but there was no significant difference compared with D+LR+H. No antagonism was noted with the addition of anticoagulants to the solutions. CONCLUSIONS: Gentamicin, tigecycline, and daptomycin in combination with anticoagulants as lock solutions displayed potent activity against common pathogens responsible for CRBSIs. Each of these lock solutions deserves strong consideration for study in a clinical trial. Further data on compatibility and stability of these solutions are needed before routine clinical use can be recommended.


Assuntos
Antibacterianos/administração & dosagem , Antibacterianos/farmacologia , Anticoagulantes/administração & dosagem , Infecções Relacionadas a Cateter/sangue , Infecções Relacionadas a Cateter/tratamento farmacológico , Soluções Isotônicas , Antibacterianos/uso terapêutico , Anticoagulantes/farmacologia , Anticoagulantes/uso terapêutico , Cateterismo Venoso Central , Contagem de Colônia Microbiana , Daptomicina/uso terapêutico , Quimioterapia Combinada , Gentamicinas/uso terapêutico , Humanos , Técnicas In Vitro , Minociclina/análogos & derivados , Minociclina/uso terapêutico , Modelos Teóricos , Tigeciclina
11.
Infect Control Hosp Epidemiol ; 28(10): 1148-54, 2007 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-17828691

RESUMO

OBJECTIVE: Transmission of Staphylococcus aureus via air may play an important role in healthcare settings. This study investigates the impact of barrier precautions on the spread of airborne S. aureus by volunteers with experimentally induced rhinovirus infection (ie, the common cold). DESIGN: Prospective nonrandomized study. SETTING: Wake Forest University School of Medicine (Winston-Salem, NC).Participants. A convenience sample of 10 individuals with nasal S. aureus carriage selected from 593 students screened for carriage. INTERVENTION: Airborne S. aureus dispersal was studied in the 10 participants under the following clothing conditions: street clothes, surgical scrubs, surgical scrubs and a gown, and the latter plus a face mask. After a 4-day baseline period, volunteers were exposed to a rhinovirus, and their clinical course was followed for 12 days. Daily swabs of nasal specimens, pharynx specimens, and skin specimens were obtained for quantitative culture, and cold symptoms were documented. Data were analyzed by random-effects negative binomial models. RESULTS: All participants developed a common cold. Incidence rate ratios (IRRs) indicated that, compared with airborne levels of S. aureus during sessions in which street clothes were worn, airborne levels decreased by 75% when surgical scrubs were worn (P<.001), by 80% when scrubs and a surgical gown were worn (P<.001), and by 82% when scrubs, a gown, and a face mask were worn (P<.001). The addition of a mask to the surgical scrubs and gown did not reduce the airborne dispersal significantly (IRR, 0.92; P>.05). Male volunteers shed twice as much S. aureus as females (incidence rate ratio, 2.04; P=.013). The cold did not alter the efficacy of the barrier precautions. CONCLUSIONS: Scrubs reduced the spread of airborne S. aureus, independent of the presence of a rhinovirus-induced cold. Airborne dispersal of S. aureus during sessions in which participants wore surgical scrubs was not significantly different from that during sessions in which gowns and gowns plus masks were also worn.


Assuntos
Portador Sadio/transmissão , Resfriado Comum/complicações , Roupa de Proteção , Infecções Estafilocócicas/prevenção & controle , Staphylococcus aureus , Adulto , Microbiologia do Ar , Controle de Doenças Transmissíveis/métodos , Tosse , Feminino , Humanos , Masculino , Material Particulado , Estudos Prospectivos , Espirro , Infecções Estafilocócicas/transmissão
12.
J Infect Dis ; 194(8): 1119-26, 2006 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-16991087

RESUMO

BACKGROUND: Staphylococcus aureus is among the most important pathogens in today's hospital setting. METHODS: The effects of sneezing on the airborne dispersal of S. aureus and other bacteria were assessed in 11 healthy nasal S. aureus carriers with experimentally induced rhinovirus colds. Airborne dispersal was studied by volumetric air sampling in 2 chamber sessions with and without histamine-induced sneezing. After 2 days of preexposure measurements, volunteers were inoculated with a rhinovirus and monitored for 14 days. Daily quantitative nasal- and skin-culture samples for bacteria and nasal-culture samples for rhinovirus were obtained, cold symptoms were assessed, and volunteer activities were recorded during sessions. RESULTS: All participants developed a cold. Sneezing caused a 4.7-fold increase in the airborne dispersal of S. aureus, a 1.4-fold increase in coagulase-negative staphylococci (CoNS), and a 3.9-fold increase in other bacteria (P < .001). An additional 2.83 colony forming units (cfu) of S. aureus/m3/min, 3.24 cfu of CoNS/m3/min, and 474.61 cfu of other bacteria/m3/min were released per sneeze. Rhinovirus exposure did not change the frequency of sneezing or airborne dispersal. Having respiratory allergies increased the spread of S. aureus by 3.8-fold during sneezing sessions (P < .001). CONCLUSION: Nasal S. aureus carriers disperse a significant amount of S. aureus into the air by sneezing. Experimental colds do not alter bacterial dispersal, but respiratory allergies multiply the effect of dispersing S. aureus.


Assuntos
Microbiologia do Ar , Transmissão de Doença Infecciosa , Infecções Estafilocócicas/transmissão , Staphylococcus aureus/isolamento & purificação , Adulto , Portador Sadio/microbiologia , Estudos de Casos e Controles , Resfriado Comum/microbiologia , Feminino , Humanos , Masculino , Mucosa Nasal/microbiologia , Rinite Alérgica Sazonal/microbiologia , Espirro , Infecções Estafilocócicas/microbiologia , Staphylococcus aureus/patogenicidade
13.
Genome Biol ; 6(8): R70, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-16086852

RESUMO

BACKGROUND: Riboswitches are RNA elements in the 5' untranslated leaders of bacterial mRNAs that directly sense the levels of specific metabolites with a structurally conserved aptamer domain to regulate expression of downstream genes. Riboswitches are most common in the genomes of low GC Gram-positive bacteria (for example, Bacillus subtilis contains examples of all known riboswitches), and some riboswitch classes seem to be restricted to this group. RESULTS: We used comparative sequence analysis and structural probing to identify five RNA elements (serC, speF, suhB, ybhL, and metA) that reside in the intergenic regions of Agrobacterium tumefaciens and many other alpha-proteobacteria. One of these, the metA motif, is found upstream of methionine biosynthesis genes and binds S-adenosylmethionine (SAM). This natural aptamer most likely functions as a SAM riboswitch (SAM-II) with a consensus sequence and structure that is distinct from the class of SAM riboswitches (SAM-I) predominantly found in Gram-positive bacteria. The minimal functional SAM-II aptamer consists of fewer than 70 nucleotides, which form a single stem and a pseudoknot. Despite its simple architecture and lower affinity for SAM, the SAM-II aptamer strongly discriminates against related compounds. CONCLUSION: SAM-II is the only metabolite-binding riboswitch class identified so far that is not found in Gram-positive bacteria, and its existence demonstrates that biological systems can use multiple RNA structures to sense a single chemical compound. The two SAM riboswitches might be 'RNA World' relics that were selectively retained in certain bacterial lineages or new motifs that have emerged since the divergence of the major bacterial groups.


Assuntos
Alphaproteobacteria/genética , Genes de Troca/genética , RNA Bacteriano/genética , Sequências Reguladoras de Ácido Ribonucleico/genética , S-Adenosilmetionina/genética , S-Adenosilmetionina/metabolismo , Aptâmeros de Nucleotídeos/genética , Sequência de Bases , Dados de Sequência Molecular , Conformação de Ácido Nucleico , Ligação Proteica , RNA Bacteriano/química
14.
Curr Opin Struct Biol ; 15(3): 342-8, 2005 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-15919195

RESUMO

Riboswitches are structured elements typically found in the 5' untranslated regions of mRNAs, where they regulate gene expression by binding to small metabolites. In all examples studied to date, these RNA control elements do not require the involvement of protein factors for metabolite binding. Riboswitches appear to be pervasive in eubacteria, suggesting that this form of regulation is an important mechanism by which metabolic genes are controlled. Recently discovered riboswitch classes have surprisingly complex mechanisms for regulating gene expression and new high-resolution structural models of these RNAs provide insight into the molecular details of metabolite recognition by natural RNA aptamers.


Assuntos
Regulação da Expressão Gênica/fisiologia , Modelos Moleculares , Biossíntese de Proteínas/genética , RNA Mensageiro/química , RNA Mensageiro/genética , Ativação Transcricional/genética , Sítios de Ligação , Conformação de Ácido Nucleico , Fatores de Transcrição/química , Fatores de Transcrição/metabolismo
15.
Infect Control Hosp Epidemiol ; 25(6): 504-11, 2004 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-15242200

RESUMO

OBJECTIVE: To investigate whether rhinovirus infection leads to increased airborne dispersal of coagulase-negative staphylococci (CoNS). DESIGN: Prospective nonrandomized intervention trial. SETTING: Wake Forest University School of Medicine, Winston-Salem, North Carolina. PARTICIPANTS: Twelve nasal Staphylococcus aureus-CoNS carriers among 685 students screened for S. aureus nasal carriage. INTERVENTIONS: Participants were studied for airborne dispersal of CoNS in a chamber under three conditions (street clothes, sterile gown with a mask, and sterile gown without a mask). After 2 days of pre-exposure measurements, volunteers were inoculated with a rhinovirus and observed for 14 days. Daily quantitative nasal and skin cultures for CoNS and nasal cultures for rhinovirus were performed. In addition, assessment of cold symptoms was performed daily, mucous samples were collected, and serum titers before and after rhinovirus inoculation were obtained. Sneezing, coughing, and talking events were recorded during chamber sessions. RESULTS: All participants had at least one nasal wash positive for rhinovirus and 10 developed a symptomatic cold. Postexposure, there was a twofold increase in airborne CoNS (P = .0004), peaking at day 12. CoNS dispersal was reduced by wearing a gown (57% reduction, P < .0001), but not a mask (P = .7). Nasal and skin CoNS colonization increased after rhinovirus infection (P < .05). CONCLUSIONS: We believe this is the first demonstration that a viral pathogen in the upper airways can increase airborne dispersal of CoNS in nasal S. aureus carriers. Gowns, gloves, and caps had a protective effect, whereas wearing a mask did not further reduce airborne spread.


Assuntos
Microbiologia do Ar , Infecção Hospitalar/transmissão , Mucosa Nasal/virologia , Infecções por Picornaviridae/transmissão , Infecções Estafilocócicas/transmissão , Staphylococcus/isolamento & purificação , Adulto , Portador Sadio/microbiologia , Portador Sadio/virologia , Coagulase/metabolismo , Contagem de Colônia Microbiana , Resfriado Comum/complicações , Resfriado Comum/transmissão , Resfriado Comum/virologia , Infecção Hospitalar/microbiologia , Infecção Hospitalar/virologia , Feminino , Humanos , Modelos Lineares , Masculino , North Carolina , Infecções por Picornaviridae/complicações , Roupa de Proteção/microbiologia , Rhinovirus/genética , Rhinovirus/isolamento & purificação , Rhinovirus/patogenicidade , Ribotipagem , Infecções Estafilocócicas/complicações , Staphylococcus/enzimologia , Staphylococcus/genética , Estudantes , Universidades
17.
Kathmandu; National Society for Earthquake Technology-Nepal (NSET-Nepal); Jan. 1999. 37 p. ilus, mapas.(Publication Series, 2).
Monografia em En | Desastres | ID: des-12360

RESUMO

Earthquakes are an unavoidable part of Kathmandu Valley's future, just as they have been a part of its past. However, a large earthquake near the Kathmandu Valley today would cause significantly greater human loss, physical damage, and economic crisis than caused by past earthquakes. With the valley's burgeoning population of almost 1 1/2 million people, uncontrolled development, and a construction practice that has actually degraded over this century, the valley is becoming increasingly vulnerable to earthquakes with each passing year. Despite this growing risk, there is no organized approach to managing earthquake risk in Kathmandu Valley, Nepal's political, economic, administrative, and cultural capital. This plan begins the process of managing that risk. The purpose of this plan is to assist His Majesty's Government of Nepal, concerned agencies, and the municipalities in Kathmandu Valley to reduce Kathmandu Valley's earthquake risk over time by identifying, coordinating and focusing risk management activities. This document outlines objectives, strategies, and specific initiatives to fulfill this purpose. It also provides background information on Kathmandu Valley's risk from earthquakes, the current status of earthquake risk management in Kathmandu Valley, and the development process of this plan. Some topics discussed in this plan are summarized in: Kathmandu Valley and Earthquakes; Current responsabilities for earthquake risk management in Kathmandu Valley; How the plan was created; Implementation strategy; Initiatives to start now and More endosed initiatives


Assuntos
Terremotos , Medição de Risco , Análise de Vulnerabilidade , Estratégias de Saúde Nacionais , 34661 , Nepal , 29654 , Reconstrução Pós-Desastre
18.
Kathmandu; National Society for Earthquake Technology-Nepal (NSET-Nepal); 1998. 24 p. ilus.(Publication Series, 2).
Monografia em En | Desastres | ID: des-12361

RESUMO

This publication describes possible impacts of a potential earthquake to affect Kathmandu Valley. Other earthquakes not evaluated in this study would produce different consequences. This is not a prediction of a specific earthquake, earthquake damage, or consequences. This description is intended only for use in planning and preparedness exercises and in raising awareness of Kathmandu Valley's earthquake risk


Assuntos
Terremotos , 29654 , Estratégias de Saúde Nacionais , 34661 , Nepal
19.
In. UN. Centre for Regional Development; Japan. Japanese Government Headquartes for the IDNDR; Aichi Prefectural Government; Japan. National Committee for the IDNDR; World Bank. Disaster Management in Metropolitan Areas for the 21st Century : Proceedings of the IDNDR Aichi/Nagoya International Conference 1993 Japan. Nagoya, UN. Centre for Regional Development, Mar. 1994. p.137-45, ilus.
Monografia em En | Desastres | ID: des-5799
20.
San Francisco, California; GeoHazards International; 1994. 8 p. ilus.
Monografia em En | Desastres | ID: des-7533
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