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1.
Mol Genet Metab Rep ; 31: 100868, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35782607

RESUMO

We have developed a fast and accurate method that uses a small volume of sample to determine over 25 of the typically reported amino acids in human plasma. Samples were prepped with a single step using a spin filter to remove proteins, avoiding the decreased sensitivity from dilution in acid precipitation. Using a reverse phase (RP) High Performance Liquid Chromatography (HPLC) system with O-phthaldehyde (OPA) as the pre-column derivatization reagent, and UV detection at 338 nm, we did a direct comparison with the most common ion exchange/ninhydrin method used in clinical labs on the same plasma samples with 95% concurrence, analysis of amino acid standard solutions returned 99% concurrence. With a sample preparation time of 30 min, utilizing less than 25 µl of sample and with a chromatography run of 30 min, this method can substantially increase access to analysis in both clinical and research laboratories using instruments that are more widely available. Synopsis: We describe a rapid and easily deployed method for sensitive amino measurement in biological samples.

2.
J Geophys Res Space Phys ; 127(10): e2022JA030751, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36591320

RESUMO

Dropout events are dramatic decreases in radiation belt electron populations that can occur in as little as 30 minutes. Loss to magnetopause due to a combination of magnetopause shadowing and outward radial transport plays a significant role in these events. We examine the dropout of relativistic electron populations during the October 2012 geomagnetic storm using simulated electron phase space density, evaluating the contribution of different processes to losses across the magnetopause. We compare loss contribution from outward transport calculated using a standard empirical radial diffusion model that assumes a dipolar geomagnetic field to an event-specific radial diffusion model evaluated with a non-dipolar geomagnetic field. We additionally evaluate the contribution of Shabansky type 1 particles, which bounce along magnetic field lines with local equatorial maxima, to the loss calculated during this event. We find that the empirical radial diffusion model with a dipolar background field underestimates the contribution of radial diffusion to this dropout event by up to 10% when compared to the event-specific, non-dipolar radial diffusion model. We additionally find that including Shabansky type 1 particles in the initial electron phase space density, that is, allowing some magnetic field lines distorted from the typical single-minima configuration in drift shell construction, increases the calculated loss by an average of 0.75%. This shows that the treatment of the geomagnetic field significantly impacts the calculation of electron losses to the magnetopause during dropout events, with the non-dipolar treatment of radial diffusion being essential to accurately quantify the loss of outer radiation belt populations.

3.
Nat Commun ; 12(1): 3553, 2021 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-34117233

RESUMO

Lightning superbolts are the most powerful and rare lightning events with intense optical emission, first identified from space. Superbolt events occurred in 2010-2018 could be localized by extracting the high energy tail of the lightning stroke signals measured by the very low frequency ground stations of the World-Wide Lightning Location Network. Here, we report electromagnetic observations of superbolts from space using Van Allen Probes satellite measurements, and ground measurements, and with two events measured both from ground and space. From burst-triggered measurements, we compute electric and magnetic power spectral density for very low frequency waves driven by superbolts, both on Earth and transmitted into space, demonstrating that superbolts transmit 10-1000 times more powerful very low frequency waves into space than typical strokes and revealing that their extreme nature is observed in space. We find several properties of superbolts that notably differ from most lightning flashes; a more symmetric first ground-wave peak due to a longer rise time, larger peak current, weaker decay of electromagnetic power density in space with distance, and a power mostly confined in the very low frequency range. Their signal is absent in space during day times and is received with a long-time delay on the Van Allen Probes. These results have implications for our understanding of lightning and superbolts, for ionosphere-magnetosphere wave transmission, wave propagation in space, and remote sensing of extreme events.

4.
Sci Adv ; 6(41)2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-33033038

RESUMO

We investigate the shape of near-Earth asteroid (101955) Bennu by constructing a high-resolution (20 cm) global digital terrain model from laser altimeter data. By modeling the northern and southern hemispheres separately, we find that longitudinal ridges previously identified in the north extend into the south but are obscured there by surface material. In the south, more numerous large boulders effectively retain surface materials and imply a higher average strength at depth to support them. The north has fewer large boulders and more evidence of boulder dynamics (toppling and downslope movement) and surface flow. These factors result in Bennu's southern hemisphere being rounder and smoother, whereas its northern hemisphere has higher slopes and a less regular shape. We infer an originally asymmetric distribution of large boulders followed by a partial disruption, leading to wedge formation in Bennu's history.

5.
Mycologia ; 111(1): 13-25, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30699058

RESUMO

The maintenance of cell shape requires finely tuned and robust vesicle trafficking in order to provide sufficient plasma membrane materials. The hyphal cells of filamentous fungi are an extreme example of cell shape maintenance due to their ability to grow rapidly and respond to the environment while keeping a relatively consistent shape. We have previously shown that two phospholipid flippases, which regulate the asymmetry of specific phospholipids within the plasma membrane, are important for hyphal growth in Aspergillus nidulans. Here, we examine the rest of the phospholipid flippases encoded by A. nidulans by obtaining single and double deletions of all four family members, dnfA, dnfB, dnfC, and dnfD. We find that deleting dnfC does not impart a noticeable phenotype, by itself or with other deletions, but that dnfD, the homolog of the essential yeast gene neo1, is important for conidiation. dnfD deletion mutants form misshapen conidiophore vesicles that are defective in metulae formation. We localize DnfD to late Golgi equivalents, where it appears just before dissociation of this organelle. We propose that DnfD functions in a trafficking process that is specifically required for the morphological changes that take place during conidiation.


Assuntos
Aspergillus nidulans/genética , Proteínas Fúngicas/fisiologia , Complexo de Golgi/enzimologia , Fosfolipídeos/fisiologia , Reprodução Assexuada , Aspergillus nidulans/enzimologia , Proteínas Fúngicas/genética , Deleção de Genes , Hifas/crescimento & desenvolvimento , Mutação , Fenótipo , Filogenia , Esporos Fúngicos
6.
J Evol Biol ; 31(2): 267-276, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-29194826

RESUMO

Females are predicted to alter sex allocation when ecological, physiological and behavioural variables have different consequences on the fitness of male and female offspring. Traditionally, tests of sex allocation have examined single causative factors, often ignoring possible interactions between multiple factors. Here, we used a multifactorial approach to examine sex allocation in the viviparous skink, Niveoscincus ocellatus. We integrated a 16-year observational field study with a manipulative laboratory experiment to explore whether the effects of the maternal thermal environment interact with the resources available to females for reproduction to affect sex allocation decisions. We found strong effects of temperature on sex allocation in the field, with females born in warm conditions and males in cold conditions; however, this was not replicated in the laboratory. In contrast, we found no effect of female resource availability on sex allocation, either independently, or in interaction with temperature. These results corresponded with an overall lack of an effect of resource availability on any of the life history traits that we predicted would mediate the benefits of differential sex allocation in this system, suggesting that selection for sex allocation in response to resource availability may be relatively weak. Combined, these results suggest that temperature may be the predominant factor driving sex allocation in this system.


Assuntos
Lagartos/fisiologia , Reprodução , Processos de Determinação Sexual , Razão de Masculinidade , Animais , Feminino , Alimentos , Luz , Masculino , Temperatura , Viviparidade não Mamífera
7.
Knee Surg Sports Traumatol Arthrosc ; 24(2): 540-5, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26658571

RESUMO

PURPOSE: To compare arthroscopic and open Latarjet performed by a single shoulder surgeon with learning curve analysis METHODS: A comparative and learning curve analysis was carried out on a prospectively gathered database of 2 consecutive series of patients treated with arthroscopic and open Latarjet procedures performed by a single shoulder surgeon between 2008 and 2014. The database included patient characteristics, ISIS scores, operative time, intra- and postoperative complications, graft and screws positioning, as well as pre- and postoperative Walch-Duplay scores. RESULTS: Sixty-four patients were included in the study, 28 in the arthroscopic group and 36 in the open group with similar age, sex ratio and preoperative ISIS score. Operative time was significantly higher in the arthroscopic group (146 versus 81 min, p = 0.001), and although no intra-operative complications were recorded in either group, there were significantly more postoperative complications in the arthroscopic group (29 vs. 11 %, p = 0.03). Screw placement was more accurate in the open group, and postoperative Walch-Duplay score did not show any significant difference between the groups (88 points in the arthroscopic group and 91 points in the open group). The arthroscopic Latarjet learning curve analysis showed that the need for conversion ceased after the first 10 patients and that surgical time came close to that of open procedure after 20 procedures. CONCLUSIONS: In this study, 10 arthroscopic Latarjet procedures were needed to overcome the need for conversion, and 20 procedures to achieve equal operating time to the open technique. Even though functional outcome and patient satisfaction were similar in both techniques, complications, screw placement inaccuracy, persistent apprehension and recurrences still remain higher with the arthroscopic technique. LEVEL OF EVIDENCE: Retrospective comparative analysis, Level III.


Assuntos
Artroscopia/métodos , Transplante Ósseo/métodos , Competência Clínica , Instabilidade Articular/cirurgia , Curva de Aprendizado , Escápula/cirurgia , Articulação do Ombro/cirurgia , Adulto , Idoso , Artroscopia/efeitos adversos , Transplante Ósseo/efeitos adversos , Feminino , Humanos , Instabilidade Articular/complicações , Masculino , Pessoa de Meia-Idade , Duração da Cirurgia , Recidiva , Estudos Retrospectivos
8.
Philos Trans A Math Phys Eng Sci ; 373(2045)2015 Jul 13.
Artigo em Inglês | MEDLINE | ID: mdl-26032317

RESUMO

We present our estimates of the thickness and volume of the Arctic Ocean ice cover from CryoSat-2 data acquired between October 2010 and May 2014. Average ice thickness and draft differences are within 0.16 m of measurements from other sources (moorings, submarine, electromagnetic sensors, IceBridge). The choice of parameters that affect the conversion of ice freeboard to thickness is discussed. Estimates between 2011 and 2013 suggest moderate decreases in volume followed by a notable increase of more than 2500 km(3) (or 0.34 m of thickness over the basin) in 2014, which could be attributed to not only a cooler summer in 2013 but also to large-scale ice convergence just west of the Canadian Arctic Archipelago due to wind-driven onshore drift. Variability of volume and thickness in the multiyear ice zone underscores the importance of dynamics in maintaining the thickness of the Arctic ice cover. Volume estimates are compared with those from ICESat as well as the trends in ice thickness derived from submarine ice draft between 1980 and 2004. The combined ICESat and CryoSat-2 record yields reduced trends in volume loss compared with the 5 year ICESat record, which was weighted by the record-setting ice extent after the summer of 2007.

9.
Rev Sci Instrum ; 85(11): 11D861, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25430274

RESUMO

A single chord two-color CO2/HeNe (10.6/0.633 µm) heterodyne laser interferometer has been designed to measure the line integral electron density along the mid-plane of the MAST Upgrade tokamak, with a typical error of 1 × 10(18) m(-3) (∼2° phase error) at 4 MHz temporal resolution. To ensure this diagnostic system can be restored from any failures without stopping MAST Upgrade operations, it has been located outside of the machine area. The final design and initial testing of this system, including details of the optics, vibration isolation, and a novel phase detection scheme are discussed in this paper.

10.
Orthop Traumatol Surg Res ; 100(1): 105-8, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24314820

RESUMO

BACKGROUND: Subclinical neurological lesions after reverse shoulder arthroplasty are frequent, mainly those involving the axillary nerve. One of the major reported risk factors is postoperative lengthening of the arm. The purpose of this study was to evaluate the anatomical relationship between the axillary nerve and prosthetic components after reverse shoulder arthroplasty. The study hypothesis was that inferior overhang of the glenosphere relative to glenoid could put this nerve at risk. MATERIAL AND METHODS: Eleven fresh frozen shoulder specimens were dissected after having undergone reverse shoulder arthroplasty using a classic deltopectoral approach. RESULTS: The mean distance from the inferior border of the glenoid to the inferior edge of the glenosphere was 6.0±4.3mm (range, 1.0 to 16.2mm). The axillary nerve was never closer than 15mm to the glenosphere. The main anterior branch of the axillary nerve was in close contact with the posterior metaphysis or humeral prosthetic implant. The mean distance between the nerve and the humeral implants was 5.2±2.1mm (range, 2.0 to 8.1mm). CONCLUSIONS: The proximity of the axillary nerve to the posterior metaphysis or humeral implants may be a risk factor for axillary nerve injury after reverse shoulder arthroplasty. CLINICAL RELEVANCE: This study quantifies the proximity of the axillary nerve to the implant after reverse shoulder arthroplasty. LEVEL OF EVIDENCE: Basic science study, cadaver study.


Assuntos
Artroplastia de Substituição/efeitos adversos , Artroplastia de Substituição/métodos , Neuropatias do Plexo Braquial/etiologia , Plexo Braquial/anatomia & histologia , Articulação do Ombro/cirurgia , Adulto , Idoso , Idoso de 80 Anos ou mais , Cadáver , Feminino , Humanos , Masculino
11.
AJNR Am J Neuroradiol ; 35(4): 691-7, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24091445

RESUMO

BACKROUND AND PURPOSE: Shoulder apprehension is defined as anxiety and resistance in patients with a history of anterior glenohumeral instability. It remains unclear whether shoulder apprehension is the result of true recurrent instability or a memorized subjective sensation. We tested whether visual presentation of apprehension videos modifies functional brain networks associated with motor resistance and anxiety. MATERIALS AND METHODS: This prospective study includes 15 consecutive right-handed male patients with shoulder apprehension (9 with right shoulder apprehension, 6 with left shoulder apprehension; 27.5 ± 6.4 years) and 10 healthy male right-handed age-matched control participants (29.0 ± 4.7 years). Multimodal MR imaging included 1) functional connectivity tensorial independent component analysis, 2) task-related general linear model analysis during visual stimulation of movies showing typical apprehension movements vs control videos, 3) voxel-based morphometry analysis of GM, and 4) tract-based spatial statistics analysis of WM. RESULTS: Patients with shoulder apprehension had significant (P < .05 corrected) increase in task-correlated functional connectivity, notably in the bilateral primary sensory-motor area and dorsolateral prefrontal cortex and, to a lesser degree, the bilateral dorsomedial prefrontal cortex, anterior insula, and dorsal anterior cingulate cortex (+148% right, +144% left). Anticorrelated functional connectivity decreased in the higher-level visual and parietal areas (-185%). There were no potentially confounding structural changes in GM or WM. CONCLUSIONS: Shoulder apprehension induces specific reorganization in apprehension-related functional connectivity of the primary sensory-motor areas (motor resistance), dorsolateral prefrontal cortex (cognitive control of motor behavior), and the dorsal anterior cingulate cortex/dorsomedial prefrontal cortex and anterior insula (anxiety and emotional regulation).


Assuntos
Ansiedade/fisiopatologia , Instabilidade Articular/fisiopatologia , Imageamento por Ressonância Magnética/métodos , Rede Nervosa/fisiopatologia , Articulação do Ombro/fisiopatologia , Adulto , Ansiedade/psicologia , Giro do Cíngulo/fisiopatologia , Humanos , Instabilidade Articular/patologia , Instabilidade Articular/psicologia , Masculino , Estimulação Luminosa/métodos , Córtex Pré-Frontal/fisiopatologia , Estudos Prospectivos , Córtex Sensório-Motor/fisiopatologia , Articulação do Ombro/patologia , Resultado do Tratamento , Adulto Jovem
12.
Rev Med Suisse ; 10(455): 2398-402, 2014 Dec 17.
Artigo em Francês | MEDLINE | ID: mdl-25752009

RESUMO

Evolution of shoulder arthroplasty has led to mainly three types of implants: hemiarthroplasty, total shoulder arthroplasty and reverse shoulder arthroplasty. There is yet no clear consensus about indications for the different existing types of prothesis. The aim of this article is therefore to bring together and clarify the indications found in the current literature. Hemiarthroplasty, historically the first widely used implant, has lost much ground to total shoulder arthroplasty, and keeps its place only for specific situations. Total shoulder arthroplasty is mainly used for centered glenohumeral osteoarthritis, whereas reverse shoulder arthroplasty is indicated for most situations in which the rotator cuff or tuberoties are deficient.


Assuntos
Artroplastia de Substituição , Prótese Articular , Articulação do Ombro/cirurgia , Árvores de Decisões , Humanos
13.
Int J Clin Pract ; 67(11): 1163-72, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23714173

RESUMO

Erectile dysfunction (ED) and cardiovascular disease (CVD) share risk factors and frequently coexist, with endothelial dysfunction believed to be the pathophysiologic link. ED is common, affecting more than 70% of men with known CVD. In addition, clinical studies have demonstrated that ED in men with no known CVD often precedes a CVD event by 2-5 years. ED severity has been correlated with increasing plaque burden in patients with coronary artery disease. ED is an independent marker of increased CVD risk including all-cause and especially CVD mortality, particularly in men aged 30-60 years. Thus, ED identifies a window of opportunity for CVD risk mitigation. We recommend that a thorough history, physical exam (including visceral adiposity), assessment of ED severity and duration and evaluation including fasting plasma glucose, lipids, resting electrocardiogram, family history, lifestyle factors, serum creatinine (estimated glomerular filtration rate) and albumin:creatinine ratio, and determination of the presence or absence of the metabolic syndrome be performed to characterise cardiovascular risk in all men with ED. Assessment of testosterone levels should also be considered and biomarkers may help to further quantify risk, even though their roles in development of CVD have not been firmly established. Finally, we recommend that a question about ED be included in assessment of CVD risk in all men and be added to CVD risk assessment guidelines.


Assuntos
Doenças Cardiovasculares/diagnóstico , Disfunção Erétil/etiologia , Papel do Médico , Adulto , Cardiologia , Doenças Cardiovasculares/mortalidade , Doenças Cardiovasculares/fisiopatologia , Endotélio Vascular/fisiologia , Disfunção Erétil/mortalidade , Disfunção Erétil/fisiopatologia , Medicina Geral , Humanos , Masculino , Pessoa de Meia-Idade , Padrões de Prática Médica , Medição de Risco , Comportamento de Redução do Risco
14.
Rev Med Suisse ; 7(322): 2489-93, 2011 Dec 21.
Artigo em Francês | MEDLINE | ID: mdl-22288288

RESUMO

Posterior glenohumeral dislocation is rare, accounting for less than 3% of all shoulder dislocations. Main etiologies are direct or indirect trauma, seizure and electrocution. The diagnosis is missed in 50 to 80% of the cases on initial presentation because of the rather subtle clinical signs compared to anterior dislocation and inadequate imaging. An unreduced posterior dislocation can lead to severely impairing complications such as recurrent instability, arthritis or avascular necrosis, requiring open reduction and complex surgery with a lower rate of success. The purpose of this article is to highlight and clarify the challenges when confronted with posterior dislocation in order to avoid misdiagnosis. Furthermore it aims to propose an adequate and comprehensible management from the initial diagnosis to the treatment.


Assuntos
Luxação do Ombro/diagnóstico , Luxação do Ombro/terapia , Algoritmos , Humanos , Radiografia , Luxação do Ombro/etiologia , Articulação do Ombro/diagnóstico por imagem
15.
Rev Sci Instrum ; 79(8): 083501, 2008 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-19044343

RESUMO

In frequency modulated continuous wave reflectometry, used for density profile measurement in fusion plasmas, it is usual to measure the beat frequency between the launched wave and the reflected wave, and from this to calculate the position of the reflecting layer in the plasma. The absolute phase of the beat signal is usually neglected. The reason is that the phase shift between sweeps is usually comparable with or more than 2pi, leading to an ambiguity that is impossible to resolve. However, recent observations on the MAST tokamak have shown that, under quiet plasma conditions (this term has to be defined), the phase shift between sweeps is small compared with 2pi and the phase ambiguity can be readily resolved. The reflectometer signal is then being analyzed as an interferometer signal would normally be, and there is a substantial improvement in spatial resolution. The method is illustrated by application to small edge localized mode precursor and allows what is believed to be the first quantitative measurement of the displacement of the plasma boundary by such a precursor mode. The errors in both the absolute phase measurement and the more conventional frequency measurement are also estimated.

16.
J Urol ; 178(4 Pt 1): 1521-7, 2007 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-17707058

RESUMO

PURPOSE: We evaluated the effects of dutasteride for preventing or delaying prostate growth and neoplastic changes in a transgenic model of prostate cancer. MATERIALS AND METHODS: Large probasin-large T antigen mice were treated for 4 or 8 weeks with dutasteride. The prostate and seminal vesicles were compared with those from intact and castrated large probasin-large T antigen mice and WT mice. RESULTS: Dutasteride greatly decreased the transgene induced increase in prostate weight but castration caused greater reduction. Dutasteride inhibited type 1 and 2, 5alpha-reductase activities, decreased DNA and protein, and increased apoptotic bodies and TUNEL staining in the dorsolateral prostate. No evidence of poorly differentiated cancer was seen. Dutasteride did not decrease the weight of the androgen dependent levator ani or bulbocavernosus muscle. CONCLUSIONS: Dutasteride inhibited type 1 and 2, 5alpha-reductase activities, and decreased DNA and protein content of the dorsolateral prostate without affecting androgen responsive muscle weight in large probasin-large T antigen mice. These studies provide support for the hypothesis that a 5alpha-reductase inhibitor inhibits the initiation and/or progression of clinical prostate cancers.


Assuntos
Inibidores de 5-alfa Redutase , Proteína de Ligação a Androgênios/genética , Antígenos Virais de Tumores/genética , Azasteroides/farmacologia , Divisão Celular/efeitos dos fármacos , Modelos Animais de Doenças , Inibidores Enzimáticos/farmacologia , Neoplasias Hormônio-Dependentes/patologia , Hiperplasia Prostática/patologia , Neoplasias da Próstata/patologia , Transgenes/genética , 3-Oxo-5-alfa-Esteroide 4-Desidrogenase , Animais , Apoptose/efeitos dos fármacos , Transformação Celular Neoplásica/efeitos dos fármacos , Transformação Celular Neoplásica/patologia , Di-Hidrotestosterona/sangue , Dutasterida , Feminino , Masculino , Proteínas de Membrana , Camundongos , Camundongos Transgênicos , Orquiectomia , Próstata/efeitos dos fármacos , Próstata/patologia , Glândulas Seminais/efeitos dos fármacos , Glândulas Seminais/patologia
17.
Infect Control Hosp Epidemiol ; 28(8): 976-82, 2007 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-17620247

RESUMO

BACKGROUND: Staphylococcus aureus is an important pathogen that leads to serious infections in the community and in hospitals. Evidence has shown that the prevalence of infection and colonization with drug-resistant S. aureus, such as methicillin-resistant S. aureus (MRSA) and glycopeptide intermediately susceptible S. aureus, is increasing. Authorities must be aware of the prevalence of MRSA infection and colonization in their country in order to implement and monitor infection control policies that help curtail further emergence of this pathogen. OBJECTIVES: To examine the trend of hospital-acquired MRSA infection and colonization in a tertiary care institution in Saudi Arabia during a 5-year period in order to identify specific areas at high risk for MRSA transmission, and to review our MRSA decolonization procedure and outcomes. METHODS: Surveillance data prospectively collected from January 1, 2000, through December 31, 2004, on hospital-acquired (HA) MRSA were analyzed, with an emphasis on the trend of HA-MRSA infection and colonization, areas of high transmission, risk factors, and effectiveness of the implemented decolonization policy. RESULTS: During the study period, 442 cases of HA-MRSA infection and colonization were identified. Of these, 51.2% were infections, and 48.8% were colonizations. An increasing trend in the incidence rates of infection and colonization was noticed during the study period, and most cases were identified on the surgical ward (33.3%) and medical ward (32.1%). Of the 34 infected patients who underwent systematic decolonization, 35.3% were successfully decolonized, and of the 11 who underwent topical decolonization, 63.6% were successfully decolonized. CONCLUSION: The increasing trend of HA-MRSA infections has been a noticeable global problem. We identified a gradual increase in the rates of MRSA colonization and infection in a tertiary care center Saudi Arabia and recognize the importance of abiding by strict infection control policies, including hand hygiene and proper isolation practices. Continued surveillance for MRSA and other emerging multidrug-resistant pathogens is also needed.


Assuntos
Infecção Hospitalar/epidemiologia , Resistência a Meticilina , Infecções Estafilocócicas/epidemiologia , Staphylococcus aureus/efeitos dos fármacos , Adulto , Feminino , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Arábia Saudita/epidemiologia , Vigilância de Evento Sentinela
18.
Eur Respir J ; 27(3): 578-84, 2006 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-16507859

RESUMO

Idiopathic pulmonary arterial hypertension (IPAH) is characterised by in situ thrombosis and increased thromboxane (Tx) A2 synthesis; however, there are no studies of antiplatelet therapy in IPAH. The aim of the current study was to determine the biochemical effects of aspirin (ASA) and clopidogrel on platelet function and eicosanoid metabolism in patients with IPAH. A randomised, double-blind, placebo-controlled crossover study of ASA 81 mg once daily and clopidogrel 75 mg once daily was performed. Plasma P-selectin levels and aggregometry were measured after exposure to adenosine diphosphate, arachidonic acid and collagen. Serum levels of TxB2 and urinary metabolites of TxA2 and prostaglandin I2 (Tx-M and PGI-M, respectively) were assessed. A total of 19 IPAH patients were enrolled, of whom nine were being treated with continuous intravenous epoprostenol. ASA and clopidogrel significantly reduced platelet aggregation to arachidonic acid and adenosine diphosphate, respectively. ASA significantly decreased serum TxB2, urinary Tx-M levels and the Tx-M/PGI-M ratio, whereas clopidogrel had no effect on eicosanoid levels. Neither drug significantly lowered plasma P-selectin levels. Epoprostenol use did not affect the results. In conclusion, aspirin and clopidogrel inhibited platelet aggregation, and aspirin reduced thromboxane metabolite production without affecting prostaglandin I2 metabolite synthesis. Further clinical trials of aspirin in patients with idiopathic pulmonary arterial hypertension should be performed.


Assuntos
Aspirina/farmacologia , Aspirina/uso terapêutico , Hipertensão Pulmonar/tratamento farmacológico , Hipertensão Pulmonar/metabolismo , Inibidores da Agregação Plaquetária/farmacologia , Inibidores da Agregação Plaquetária/uso terapêutico , Agregação Plaquetária/efeitos dos fármacos , Tromboxano A2/biossíntese , Ticlopidina/análogos & derivados , Adulto , Clopidogrel , Estudos Cross-Over , Método Duplo-Cego , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Ticlopidina/farmacologia , Ticlopidina/uso terapêutico
19.
J Hosp Infect ; 62(2): 207-13, 2006 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-16307822

RESUMO

The aim of this study was to determine the rate, risk factors and outcomes of catheter-related bloodstream infections (CRBSIs) in patients in a paediatric intensive care unit (PICU). A prospective cohort study was performed in King Abdulaziz Medical City, Riyadh, Saudi Arabia; a 650-bed academic/tertiary care centre with a combined 10-bed medical and surgical PICU. All patients admitted to the PICU from July 2000 to February 2003 who had a central line placed were monitored for the development of bloodstream infection (BSI) from insertion until 48 h after removal. Four hundred and forty-six patients with 2493 central-line-days were documented; 273 (55%) were male and the mean age was 2.6 years. Of the 446 patients, 278 (56%) had congenital heart disease, 108 (22%) had genetic disorders and/or congenital malformations, 55 (11%) had respiratory disease, and 42 (8%) had trauma. There were 50 episodes of CRBSI in 46 patients with a rate of 20.06 per 1,000 central-line-days and a device-utilization rate of 57%. Of these 50 episodes, 24 (48%) were polymicrobial, 16 (32%) were due to Gram-negative organisms, five (10%) were due to Gram-positive organisms, and five (10%) were fungal. The most common organisms isolated were Klebsiella pneumoniae (N=12, 16%), coagulase-negative staphylococci (N=10, 14%) and Pseudomonas aeruginosa (N=8, 11%). The mean duration of line insertion was 11.8 days for CRBSI patients and 4.22 days for non-BSI patients (P<0.0001). The mean PICU stay was 30.20 days for CRBSI patients and 6.35 days for non-BSI patients (P<0.0001). BSI occurred more often in catheters inserted in the PICU compared with the operating room, and in the femoral site compared with jugular or subclavian sites (P<0.001). In multiple logistic regression analysis of the risk factors, CRBSI patients were more likely to have multiple central lines [odds ratio (OR) 9.19; 95% confidence intervals (CI): 3.76-22.43), the line was more likely to be used for total parenteral nutrition (OR: 8.69; 95% CI: 3.5-21.4), and guidewire exchange was more likely to be performed on the line. CRBSI was not associated with a higher mortality rate. The CRBSI rate in our hospital is high compared with that reported by the National Nosocomial Infection Surveillance system. This study has established a benchmark for future comparisons. Additional studies from Saudi Arabia are necessary for national comparison and development of preventive measures.


Assuntos
Cateterismo Venoso Central/efeitos adversos , Unidades de Terapia Intensiva Pediátrica , Bacteriemia/epidemiologia , Bacteriemia/etiologia , Candida/isolamento & purificação , Pré-Escolar , Estudos de Coortes , Infecção Hospitalar/epidemiologia , Infecção Hospitalar/etiologia , Feminino , Bactérias Gram-Negativas/isolamento & purificação , Bactérias Gram-Positivas/isolamento & purificação , Humanos , Lactente , Masculino , Estudos Prospectivos , Fatores de Risco , Arábia Saudita
20.
Prostate ; 66(4): 369-76, 2006 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-16302273

RESUMO

BACKGROUND: 7-alpha-methyl-19-nortestosterone (MENT) is being considered for androgen replacement in testosterone deficient men and as a male contraceptive. Because androgenic effects on the prostate are a major concern, we have evaluated MENT in a transgenic model of prostate cancer. METHODS: LPB-Tag mice were castrated and infused with testosterone (T; 5 or 30 microg/day) or MENT (5 or 30 microg/day) for 4 weeks. Prostate, seminal vesicle, and levator ani muscle (LAM) weights were compared. RESULTS: At an equivalent dose, MENT maintained or stimulated the mean weights of these organs more than T. However, the dorsolateral prostate/LAM ratio of weights did not favor MENT, but DNA/mg tissue and Ki 67 immunostaining suggested that MENT may increase DNA less than T. CONCLUSIONS: MENT is more potent than T in maintaining or stimulating prostate, seminal vesicle, and LAM. Using doses that resulted in comparable stimulation of the levator ani muscle, MENT had similar effect on prostate weight, but increased DNA/mg prostate less than T in this transgenic mouse model of prostate cancer.


Assuntos
Estrenos/farmacologia , Neoplasias da Próstata/patologia , Testículo/efeitos dos fármacos , Testosterona/fisiologia , Animais , Anticoncepcionais Masculinos/farmacologia , DNA/biossíntese , Feminino , Terapia de Reposição Hormonal , Masculino , Camundongos , Camundongos Transgênicos , Músculo Esquelético/efeitos dos fármacos , Músculo Esquelético/crescimento & desenvolvimento , Testículo/crescimento & desenvolvimento , Testosterona/deficiência
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