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1.
Curr Sports Med Rep ; 22(6): 224-229, 2023 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-37294198

RESUMO

ABSTRACT: The growth of electronic sports (esports), or competitive video gaming, in recent years has led to an increasing number of players seeking care for injuries and injury prevention associated with esports. In addition, the increase of esports players seeking care from health care professionals leads to a heightened awareness about the role of health and lifestyle in esports performance.Unfortunately, few health care professionals are familiar with the physical and mental demands of this sport or are comfortable addressing the needs of this athletic population and the issues that they encounter affecting their health and their sport. This article offers an overview of common esports health issues and considerations specific to esports athletic care for the sports medicine physician in support of optimizing the care of these patients.


Assuntos
Medicina Esportiva , Esportes , Jogos de Vídeo , Humanos , Atletas , Exame Físico
2.
J Clin Anesth ; 27(2): 97-104, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25605048

RESUMO

STUDY OBJECTIVE: To determine the difference between the Hispanic and non-Hispanic public's knowledge about anesthesia, anesthesiologist's expertise, and role of the anesthesiologist in and out of the operating room (OR). DESIGN: Cross-sectional survey. SETTING: Los Angeles inner-city county hospital preoperative anesthesia clinic. PATIENTS: Predominantly Hispanic population. INTERVENTIONS: A 54-question survey in English and Spanish was distributed to adult patients. MEASUREMENTS: Demographic data, knowledge of the anesthesiologist's roles/responsibilities, knowledge of anesthesia, trust in anesthesiologists, and fears related to anesthesia were collected. Descriptive analysis and multiple regression analysis of the data were used to report knowledge, trust, and fear, and the predictive role of patient characteristics. MAIN RESULTS: 300 (88% of eligible pts) completed the survey. Patient demographics were as follows: Hispanics (73%), female (63%), mean age 47 ± 14 years, high school-educated or below (71%), previous surgery (67%), possessing a chronic medical condition (49%), self-reported health of fair to poor (58%). Seventy percent of patients recognized anesthesiologists as specially trained doctors. Mean ± SD trust scores in doctors were 2.6 ± 1.2 out of a maximum 4. Patients with a better perception of their self-health (P < 0.01) and with higher knowledge scores (P < 0.01) had significantly higher trust in the doctors. Women (P = 0.01) patients, those patients with chronic medical condition (P < 0.02), and patients with greater knowledge scores had greater fear or concerns about anesthesia. Mean ± SD knowledge score about anesthesia was 6.3 ± 2.8 (range 0-13). Patients who had surgery previously (P < 0.01) had higher knowledge scores. CONCLUSION: Most Hispanic patients believe that anesthesiologists are specialist doctors and that they put patients to sleep, but these patients are uncertain of their exact role or function during surgery or outside of the OR. High concerns or fears about devastating but rare complications of anesthesia remain. Educational efforts should be directed at this group especially, with the goal of alleviating preoperative anxiety.


Assuntos
Anestesia/psicologia , Anestesiologia/organização & administração , Conhecimentos, Atitudes e Prática em Saúde/etnologia , Hispânico ou Latino/psicologia , Papel do Médico , Adulto , Anestesia/efeitos adversos , Anestesiologia/educação , California , Competência Clínica , Educação de Pós-Graduação em Medicina , Medo/psicologia , Feminino , Hispânico ou Latino/estatística & dados numéricos , Humanos , Masculino , Pessoa de Meia-Idade , Relações Médico-Paciente , Inquéritos e Questionários , Confiança/psicologia , Saúde da População Urbana/estatística & dados numéricos
3.
J Biol Chem ; 289(39): 27264-27277, 2014 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-25100731

RESUMO

For a subset of pathogenic microorganisms, including Streptococcus pneumoniae, the recognition and degradation of host hyaluronan contributes to bacterial spreading through the extracellular matrix and enhancing access to host cell surfaces. The hyaluronate lyase (Hyl) presented on the surface of S. pneumoniae performs this role. Using glycan microarray screening, affinity electrophoresis, and isothermal titration calorimetry we show that the N-terminal module of Hyl is a hyaluronan-specific carbohydrate-binding module (CBM) and the founding member of CBM family 70. The 1.2 Å resolution x-ray crystal structure of CBM70 revealed it to have a ß-sandwich fold, similar to other CBMs. The electrostatic properties of the binding site, which was identified by site-directed mutagenesis, are distinct from other CBMs and complementary to its acidic ligand, hyaluronan. Dynamic light scattering and solution small angle x-ray scattering revealed the full-length Hyl protein to exist as a monomer/dimer mixture in solution. Through a detailed analysis of the small angle x-ray scattering data, we report the pseudoatomic solution structures of the monomer and dimer forms of the full-length multimodular Hyl.


Assuntos
Proteínas de Bactérias/química , Polissacarídeo-Liases/química , Multimerização Proteica , Streptococcus pneumoniae/enzimologia , Proteínas de Bactérias/genética , Cristalografia por Raios X , Mutagênese Sítio-Dirigida , Polissacarídeo-Liases/genética , Estrutura Quaternária de Proteína , Estrutura Terciária de Proteína , Streptococcus pneumoniae/genética
4.
PLoS One ; 9(7): e103128, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25054772

RESUMO

Marine microbes degrade dimethylsulfoniopropionate (DMSP), which is produced in large quantities by marine algae and plants, with DMSP lyases into acrylate and the gas dimethyl sulfide (DMS). Approximately 10% of the DMS vents from the sea into the atmosphere and this emission returns sulfur, which arrives in the sea through rivers and runoff, back to terrestrial systems via clouds and rain. Despite their key role in this sulfur cycle DMSP lyases are poorly understood at the molecular level. Here we report the first X-ray crystal structure of the putative DMSP lyase RdDddP from Roseobacter denitrificans, which belongs to the abundant DddP family. This structure, determined to 2.15 Å resolution, shows that RdDddP is a homodimeric metalloprotein with a binuclear center of two metal ions located 2.7 Å apart in the active site of the enzyme. Consistent with the crystallographic data, inductively coupled plasma mass spectrometry (ICP-MS) and total reflection X-ray fluorescence (TRXF) revealed the bound metal species to be primarily iron. A 3D structure guided analysis of environmental DddP lyase sequences elucidated the critical residues for metal binding are invariant, suggesting all proteins in the DddP family are metalloenzymes.


Assuntos
Liases de Carbono-Enxofre/química , Roseobacter/enzimologia , Sequência de Aminoácidos , Liases de Carbono-Enxofre/metabolismo , Cristalografia por Raios X , Modelos Moleculares , Dados de Sequência Molecular , Conformação Proteica , Roseobacter/química , Roseobacter/metabolismo , Sulfetos/metabolismo , Compostos de Sulfônio/metabolismo , Enxofre/metabolismo
5.
J Urol ; 192(6): 1856-63, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24866596

RESUMO

PURPOSE: Catheter associated urinary tract infections are one of the most common health care associated infections. The condition is frequently complicated by encrustation, which blocks the catheter lumen. Preclinical research is limited by the lack of relevant high throughput and cost-effective animal models. Current models are restricted to female mice, associated with major transurethral loss of catheter materials during micturition, highly invasive and complex. We present an ultrasound guided, minimally invasive model that enables catheter associated urinary tract infection and catheter encrustation studies in each mouse gender. MATERIALS AND METHODS: Catheter segments (4 mm) were implanted in murine bladders percutaneously in 15 males and 5 females, and transurethrally in 15 females using the Seldinger technique under ultrasound guidance. Proteus mirabilis was instilled intraluminally. Catheter encrustation was monitored by ultrasound. Bacteria were quantified in urine, and catheters and encrustation were analyzed on day 6 or 21. RESULTS: Percutaneous and transurethral catheter implantations were performed in a mean ± SE 3.6 ± 0.8 vs 2.5 ± 0.5 minutes in all mice. Ultrasound confirmed that 100% and 66% of implanted catheters, respectively, remained indwelling during the study period. Catheter encrustation developed in P. mirabilis infected urine 48 hours after instillation and an increase with time was detected by ultrasound. Fourier transform spectroscopy of the encrustation confirmed a typical struvite spectrum. Control catheters remained sterile during 21 days. CONCLUSIONS: Our minimally invasive, reproducible percutaneous technique is suitable for studying catheter associated urinary tract infection in each gender. Infecting urine with P. mirabilis generates a preclinical model of catheter encrustation within 3 days. The progression of encrustation can be monitored in vivo by ultrasound, making this image based model suitable for assessing novel antibacterial and anti-encrustation therapies.


Assuntos
Infecções Relacionadas a Cateter/diagnóstico por imagem , Infecções Relacionadas a Cateter/etiologia , Modelos Animais de Doenças , Infecções por Proteus/diagnóstico por imagem , Infecções por Proteus/etiologia , Proteus mirabilis , Cateterismo Urinário/efeitos adversos , Infecções Urinárias/diagnóstico por imagem , Infecções Urinárias/etiologia , Animais , Feminino , Masculino , Camundongos , Ultrassonografia
6.
J Biol Chem ; 286(17): 15577-85, 2011 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-21388965

RESUMO

The phenylacetic acid (PAA) degradation pathway is the sole aerobic route for phenylacetic acid metabolism in bacteria and facilitates degradation of environmental pollutants such as styrene and ethylbenzene. The PAA pathway also is implicated in promoting Burkholderia cenocepacia infections in cystic fibrosis patients. Intriguingly, the first enzyme in the PAA pathway is present in two copies (paaK1 and paaK2), yet each subsequent enzyme is present in only a single copy. Furthermore, sequence divergence indicates that PaaK1 and PaaK2 form a unique subgroup within the adenylate-forming enzyme (AFE) superfamily. To establish a biochemical rationale for the existence of the PaaK paralogs in B. cenocepacia, we present high resolution x-ray crystal structures of a selenomethionine derivative of PaaK1 in complex with ATP and adenylated phenylacetate intermediate complexes of PaaK1 and PaaK2 in distinct conformations. Structural analysis reveals a novel N-terminal microdomain that may serve to recruit subsequent PAA enzymes, whereas a bifunctional role is proposed for the P-loop in stabilizing the C-terminal domain in conformation 2. The potential for different kinetic profiles was suggested by a structurally divergent extension of the aryl substrate pocket in PaaK1 relative to PaaK2. Functional characterization confirmed this prediction, with PaaK1 possessing a lower K(m) for phenylacetic acid and better able to accommodate 3' and 4' substitutions on the phenyl ring. Collectively, these results offer detailed insight into the reaction mechanism of a novel subgroup of the AFE superfamily and provide a clear biochemical rationale for the presence of paralogous copies of PaaK of B. cenocepacia.


Assuntos
Burkholderia cenocepacia/enzimologia , Coenzima A Ligases/química , Trifosfato de Adenosina , Cristalografia por Raios X , Fibrose Cística , Cinética , Ligantes , Fenilacetatos , Conformação Proteica
7.
Acta Crystallogr Sect F Struct Biol Cryst Commun ; 65(Pt 10): 1001-3, 2009 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-19851006

RESUMO

Burkholderia xenovorans LB400 harbours two paralogous copies of the recently discovered benzoate oxidation (box) pathway. While both copies are functional, the paralogues are differentially regulated and flanked by putative transcriptional regulators from distinct families. The putative LysR-type transcriptional regulator (LTTR) adjacent to the megaplasmid-encoded box enzymes, Bxe_C0898, has been produced recombinantly in Escherichia coli and purified to homogeneity. Gel-filtration studies show that Bxe_C0898 is a tetramer in solution, consistent with previously characterized LTTRs. Bxe_C0898 crystallized with four molecules in the asymmetric unit of the P4(3)2(1)2/P4(1)2(1)2 unit cell with a solvent content of 61.19%, as indicated by processing of the X-ray diffraction data. DNA-protection assays are currently under way in order to identify potential operator regions for this LTTR and to define its role in regulation of the box pathway.


Assuntos
Proteínas de Bactérias/isolamento & purificação , Benzoatos/metabolismo , Burkholderia/metabolismo , Fatores de Transcrição/isolamento & purificação , Proteínas de Bactérias/química , Clonagem Molecular , Cristalização , Oxirredução , Fatores de Transcrição/química
8.
J Mol Biol ; 392(2): 393-404, 2009 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-19591842

RESUMO

Cyanophycin, or poly-L-Asp-multi-L-Arg, is a non-ribosomally synthesized peptidic polymer that is used for nitrogen storage by cyanobacteria and other select eubacteria. Upon synthesis, it self-associates to form insoluble granules, the degradation of which is uniquely catalyzed by a carboxy-terminal-specific protease, cyanophycinase. We have determined the structure of cyanophycinase from the freshwater cyanobacterium Synechocystis sp. PCC6803 at 1.5-A resolution, showing that the structure is dimeric, with individual protomers resembling aspartyl dipeptidase. Kinetic characterization of the enzyme demonstrates that the enzyme displays Michaelis-Menten kinetics with a k(cat) of 16.5 s(-1) and a k(cat)/K(M) of 7.5x10(-6) M(-1) s(-1). Site-directed mutagenesis experiments confirm that cyanophycinase is a serine protease and that Gln101, Asp172, Gln173, Arg178, Arg180 and Arg183, which form a conserved pocket adjacent to the catalytic Ser132, are functionally critical residues. Modeling indicates that cyanophycinase binds the beta-Asp-Arg dipeptide residue immediately N-terminal to the scissile bond in an extended conformation in this pocket, primarily recognizing this penultimate beta-Asp-Arg residue of the polymeric chain. Because binding and catalysis depend on substrate features unique to beta-linked aspartyl peptides, cyanophycinase is able to act within the cytosol without non-specific cleavage events disrupting essential cellular processes.


Assuntos
Peptídeo Hidrolases/química , Peptídeo Hidrolases/metabolismo , Proteínas de Plantas/metabolismo , Synechocystis/enzimologia , Proteínas de Bactérias , Cristalografia por Raios X , Dimerização , Cinética , Modelos Biológicos , Modelos Moleculares , Mutagênese Sítio-Dirigida , Peptídeo Hidrolases/genética , Estrutura Quaternária de Proteína
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