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1.
Nature ; 602(7895): 63-67, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-35110756

RESUMO

Electrically charged particles can be created by the decay of strong enough electric fields, a phenomenon known as the Schwinger mechanism1. By electromagnetic duality, a sufficiently strong magnetic field would similarly produce magnetic monopoles, if they exist2. Magnetic monopoles are hypothetical fundamental particles that are predicted by several theories beyond the standard model3-7 but have never been experimentally detected. Searching for the existence of magnetic monopoles via the Schwinger mechanism has not yet been attempted, but it is advantageous, owing to the possibility of calculating its rate through semi-classical techniques without perturbation theory, as well as that the production of the magnetic monopoles should be enhanced by their finite size8,9 and strong coupling to photons2,10. Here we present a search for magnetic monopole production by the Schwinger mechanism in Pb-Pb heavy ion collisions at the Large Hadron Collider, producing the strongest known magnetic fields in the current Universe11. It was conducted by the MoEDAL experiment, whose trapping detectors were exposed to 0.235 per nanobarn, or approximately 1.8 × 109, of Pb-Pb collisions with 5.02-teraelectronvolt center-of-mass energy per collision in November 2018. A superconducting quantum interference device (SQUID) magnetometer scanned the trapping detectors of MoEDAL for the presence of magnetic charge, which would induce a persistent current in the SQUID. Magnetic monopoles with integer Dirac charges of 1, 2 and 3 and masses up to 75 gigaelectronvolts per speed of light squared were excluded by the analysis at the 95% confidence level. This provides a lower mass limit for finite-size magnetic monopoles from a collider search and greatly extends previous mass bounds.

2.
N Engl J Med ; 389(15): 1357-1367, 2023 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-37819954

RESUMO

BACKGROUND: Adjunctive glucocorticoids are widely used to treat human immunodeficiency virus (HIV)-associated tuberculous meningitis despite limited data supporting their safety and efficacy. METHODS: We conducted a double-blind, randomized, placebo-controlled trial involving HIV-positive adults (≥18 years of age) with tuberculous meningitis in Vietnam and Indonesia. Participants were randomly assigned to receive a 6-to-8-week tapering course of either dexamethasone or placebo in addition to 12 months of antituberculosis chemotherapy. The primary end point was death from any cause during the 12 months after randomization. RESULTS: A total of 520 adults were randomly assigned to receive either dexamethasone (263 participants) or placebo (257 participants). The median age was 36 years; 255 of 520 participants (49.0%) had never received antiretroviral therapy, and 251 of 484 participants (51.9%) with available data had a baseline CD4 count of 50 cells per cubic millimeter or less. Six participants withdrew from the trial, and five were lost to follow-up. During the 12 months of follow-up, death occurred in 116 of 263 participants (44.1%) in the dexamethasone group and in 126 of 257 participants (49.0%) in the placebo group (hazard ratio, 0.85; 95% confidence interval, 0.66 to 1.10; P = 0.22). Prespecified analyses did not reveal a subgroup that clearly benefited from dexamethasone. The incidence of secondary end-point events, including cases of immune reconstitution inflammatory syndrome during the first 6 months, was similar in the two trial groups. The numbers of participants with at least one serious adverse event were similar in the dexamethasone group (192 of 263 participants [73.0%]) and the placebo group (194 of 257 participants [75.5%]) (P = 0.52). CONCLUSIONS: Among HIV-positive adults with tuberculous meningitis, adjunctive dexamethasone, as compared with placebo, did not confer a benefit with respect to survival or any secondary end point. (Funded by the Wellcome Trust; ACT HIV ClinicalTrials.gov number, NCT03092817.).


Assuntos
Antirretrovirais , Antituberculosos , Dexametasona , Glucocorticoides , Infecções por HIV , Tuberculose Meníngea , Adulto , Humanos , Dexametasona/efeitos adversos , Dexametasona/uso terapêutico , Método Duplo-Cego , Glucocorticoides/efeitos adversos , Glucocorticoides/uso terapêutico , HIV , Infecções por HIV/complicações , Infecções por HIV/tratamento farmacológico , Soropositividade para HIV/complicações , Soropositividade para HIV/tratamento farmacológico , Tuberculose Meníngea/complicações , Tuberculose Meníngea/tratamento farmacológico , Antituberculosos/efeitos adversos , Antituberculosos/uso terapêutico , Quimioterapia Combinada/efeitos adversos , Antirretrovirais/efeitos adversos , Antirretrovirais/uso terapêutico
3.
Proc Natl Acad Sci U S A ; 120(47): e2307773120, 2023 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-37963246

RESUMO

The expansion and intensification of livestock production is predicted to promote the emergence of pathogens. As pathogens sometimes jump between species, this can affect the health of humans as well as livestock. Here, we investigate how livestock microbiota can act as a source of these emerging pathogens through analysis of Streptococcus suis, a ubiquitous component of the respiratory microbiota of pigs that is also a major cause of disease on pig farms and an important zoonotic pathogen. Combining molecular dating, phylogeography, and comparative genomic analyses of a large collection of isolates, we find that several pathogenic lineages of S. suis emerged in the 19th and 20th centuries, during an early period of growth in pig farming. These lineages have since spread between countries and continents, mirroring trade in live pigs. They are distinguished by the presence of three genomic islands with putative roles in metabolism and cell adhesion, and an ongoing reduction in genome size, which may reflect their recent shift to a more pathogenic ecology. Reconstructions of the evolutionary histories of these islands reveal constraints on pathogen emergence that could inform control strategies, with pathogenic lineages consistently emerging from one subpopulation of S. suis and acquiring genes through horizontal transfer from other pathogenic lineages. These results shed light on the capacity of the microbiota to rapidly evolve to exploit changes in their host population and suggest that the impact of changes in farming on the pathogenicity and zoonotic potential of S. suis is yet to be fully realized.


Assuntos
Infecções Estreptocócicas , Streptococcus suis , Doenças dos Suínos , Animais , Humanos , Suínos , Infecções Estreptocócicas/veterinária , Fazendas , Doenças dos Suínos/epidemiologia , Virulência/genética , Streptococcus suis/genética , Gado
4.
J Infect Dis ; 228(3): 343-352, 2023 08 11.
Artigo em Inglês | MEDLINE | ID: mdl-36823694

RESUMO

BACKGROUND: The purpose of this study was to assess if single nucleotide polymorphisms (SNPs) in lung mucins MUC5B and MUC5AC are associated with Mycobacterium tuberculosis outcomes. METHODS: Independent SNPs in MUC5B and MUC5AC (genotyped by Illumina HumanOmniExpress array) were assessed for associations with tumor necrosis factor (TNF) concentrations (measured by immunoassay) in cerebral spinal fluid (CSF) from tuberculous meningitis (TBM) patients. SNPs associated with CSF TNF concentrations were carried forward for analyses of pulmonary and meningeal tuberculosis susceptibility and TBM mortality. RESULTS: MUC5AC SNP rs28737416 T allele was associated with lower CSF concentrations of TNF (P = 1.8 × 10-8) and IFN-γ (P = 2.3 × 10-6). In an additive genetic model, rs28737416 T/T genotype was associated with higher susceptibility to TBM (odds ratio [OR], 1.24; 95% confidence interval [CI], 1.03-1.49; P = .02), but not pulmonary tuberculosis (OR, 1.11, 95% CI, .98-1.25; P = .10). TBM mortality was higher among participants with the rs28737416 T/T and T/C genotypes (35/119, 30.4%) versus the C/C genotype (11/89, 12.4%; log-rank P = .005) in a Vietnam discovery cohort (n = 210), an independent Vietnam validation cohort (n = 87; 9/87, 19.1% vs 1/20, 2.5%; log-rank P = .02), and an Indonesia validation cohort (n = 468, 127/287, 44.3% vs 65/181, 35.9%; log-rank P = .06). CONCLUSIONS: MUC5AC variants may contribute to immune changes that influence TBM outcomes.


Assuntos
Mycobacterium tuberculosis , Tuberculose Meníngea , Humanos , Tuberculose Meníngea/genética , Tuberculose Meníngea/complicações , Citocinas/genética , Genótipo , Fator de Necrose Tumoral alfa/genética , Polimorfismo de Nucleotídeo Único , Mucina-5AC/genética
5.
J Autoimmun ; 138: 103046, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37229810

RESUMO

Juvenile idiopathic arthritis (JIA) is an autoimmune, inflammatory joint disease with complex genetic etiology. Previous GWAS have found many genetic loci associated with JIA. However, the biological mechanism behind JIA remains unknown mainly because most risk loci are located in non-coding genetic regions. Interestingly, increasing evidence has found that regulatory elements in the non-coding regions can regulate the expression of distant target genes through spatial (physical) interactions. Here, we used information on the 3D genome organization (Hi-C data) to identify target genes that physically interact with SNPs within JIA risk loci. Subsequent analysis of these SNP-gene pairs using data from tissue and immune cell type-specific expression quantitative trait loci (eQTL) databases allowed the identification of risk loci that regulate the expression of their target genes. In total, we identified 59 JIA-risk loci that regulate the expression of 210 target genes across diverse tissues and immune cell types. Functional annotation of spatial eQTLs within JIA risk loci identified significant overlap with gene regulatory elements (i.e., enhancers and transcription factor binding sites). We found target genes involved in immune-related pathways such as antigen processing and presentation (e.g., ERAP2, HLA class I and II), the release of pro-inflammatory cytokines (e.g., LTBR, TYK2), proliferation and differentiation of specific immune cell types (e.g., AURKA in Th17 cells), and genes involved in physiological mechanisms related to pathological joint inflammation (e.g., LRG1 in arteries). Notably, many of the tissues where JIA-risk loci act as spatial eQTLs are not classically considered central to JIA pathology. Overall, our findings highlight the potential tissue and immune cell type-specific regulatory changes contributing to JIA pathogenesis. Future integration of our data with clinical studies can contribute to the development of improved JIA therapy.


Assuntos
Artrite Juvenil , Humanos , Artrite Juvenil/genética , Regulação da Expressão Gênica , Locos de Características Quantitativas , Diferenciação Celular , Polimorfismo de Nucleotídeo Único , Estudo de Associação Genômica Ampla , Predisposição Genética para Doença , Aminopeptidases/genética
6.
Dev Dyn ; 251(8): 1291-1305, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35355366

RESUMO

BACKGROUND: The gut visceral musculature plays essential roles in not only moving substances through the lumen but also maintaining the function and physiology of the gut. Although the development of the visceral musculature has been studied in multiple model organisms, how it degenerates is poorly understood. RESULTS: Here, we employ the Drosophila midgut as a model to demonstrate that the visceral musculature is disrupted by intrinsic and extrinsic factors, such as aging, feeding, chemical-induced tissue damage, and oncogenic transformation in the epithelium. Notably, we define four prominent visceral musculature disruption phenotypes, which we refer as "sprout," "discontinuity," "furcation," and "crossover" of the longitudinal muscle. Given that the occurrence of these phenotypes is increased during aging and under various stresses, we propose that these phenotypes can be used as quantitative readouts of deterioration of the visceral musculature. Intriguingly, administration of a tissue-damaging chemical dextran sulfate sodium (DSS) induced similar visceral musculature disruption phenotypes in zebrafish larvae, indicating that ingestion of a tissue-damaging chemical can disrupt the visceral musculature in a vertebrate as well. CONCLUSIONS: Our study provides insights into the deterioration of the gut visceral musculature and lays a groundwork for investigating the underlying mechanisms in Drosophila as well as other animals.


Assuntos
Proteínas de Drosophila , Peixe-Zebra , Animais , Drosophila/genética , Proteínas de Drosophila/genética , Endoderma , Músculos
7.
Phys Rev Lett ; 129(19): 195002, 2022 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-36399755

RESUMO

The application of an external 26 Tesla axial magnetic field to a D_{2} gas-filled capsule indirectly driven on the National Ignition Facility is observed to increase the ion temperature by 40% and the neutron yield by a factor of 3.2 in a hot spot with areal density and temperature approaching what is required for fusion ignition [1]. The improvements are determined from energy spectral measurements of the 2.45 MeV neutrons from the D(d,n)^{3}He reaction, and the compressed central core B field is estimated to be ∼4.9 kT using the 14.1 MeV secondary neutrons from the D(T,n)^{4}He reactions. The experiments use a 30 kV pulsed-power system to deliver a ∼3 µs current pulse to a solenoidal coil wrapped around a novel high-electrical-resistivity AuTa_{4} hohlraum. Radiation magnetohydrodynamic simulations are consistent with the experiment.

8.
BMC Biol ; 19(1): 191, 2021 09 07.
Artigo em Inglês | MEDLINE | ID: mdl-34493269

RESUMO

BACKGROUND: Antimicrobial resistance (AMR) is among the gravest threats to human health and food security worldwide. The use of antimicrobials in livestock production can lead to emergence of AMR, which can have direct effects on humans through spread of zoonotic disease. Pigs pose a particular risk as they are a source of zoonotic diseases and receive more antimicrobials than most other livestock. Here we use a large-scale genomic approach to characterise AMR in Streptococcus suis, a commensal found in most pigs, but which can also cause serious disease in both pigs and humans. RESULTS: We obtained replicated measures of Minimum Inhibitory Concentration (MIC) for 16 antibiotics, across a panel of 678 isolates, from the major pig-producing regions of the world. For several drugs, there was no natural separation into 'resistant' and 'susceptible', highlighting the need to treat MIC as a quantitative trait. We found differences in MICs between countries, consistent with their patterns of antimicrobial usage. AMR levels were high even for drugs not used to treat S. suis, with many multidrug-resistant isolates. Similar levels of resistance were found in pigs and humans from regions associated with zoonotic transmission. We next used whole genome sequences for each isolate to identify 43 candidate resistance determinants, 22 of which were novel in S. suis. The presence of these determinants explained most of the variation in MIC. But there were also interesting complications, including epistatic interactions, where known resistance alleles had no effect in some genetic backgrounds. Beta-lactam resistance involved many core genome variants of small effect, appearing in a characteristic order. CONCLUSIONS: We present a large dataset allowing the analysis of the multiple contributing factors to AMR in S. suis. The high levels of AMR in S. suis that we observe are reflected by antibiotic usage patterns but our results confirm the potential for genomic data to aid in the fight against AMR.


Assuntos
Streptococcus suis , Animais , Antibacterianos/farmacologia , Anti-Infecciosos , Farmacorresistência Bacteriana/genética , Genômica , Testes de Sensibilidade Microbiana , Preparações Farmacêuticas , Streptococcus suis/efeitos dos fármacos , Streptococcus suis/genética , Suínos
9.
Tech Coloproctol ; 23(7): 639-647, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31317361

RESUMO

BACKGROUND: Treatment of a perianal fistula is difficult due to the risk of fecal incontinence and recurrence. The ligation of intersphincteric tract (LIFT) procedure is a sphincter-saving procedure associated with success rates ranging from 57 to 94%. The aim of our study was to find predictors for a favorable outcome of the LIFT procedure, evaluation of postoperative fecal incontinence, quality of life, and subsequent treatment with long-term follow-up. METHODS: This study was performed in patients who underwent LIFT between 2013 and 2015 at our institution. Their medical data were retrieved from the electronic patient files. The fistula characteristics were described by physical examination, three-dimensional endoanal ultrasound, and perioperative evaluation. Recurrence rate, postoperative fecal incontinence, and quality of life were assessed with the Patient-Reported Outcome Measurement (PROM). Thirty-two months later, long-term follow-up including subsequent procedures was evaluated. RESULTS: Forty-five patients [17 men, mean age 40 years (range 24-67 years)] were included. In 41 (84%) patients, the fistula was classified as complex; 32 (71%) were referrals with a history of previous fistula surgery. The initial success rate was 18 (40%). Only the height of the internal fistula opening (≥ 15 mm p < 0.03) was associated with recurrence. The LIFT procedure did not affect the occurrence of fecal incontinence or soiling. Recurrence showed a trend with a lower PROM (p = 0.07). Twenty-four months later, further surgery leads to cure in 34 (75%), asymptomatic fistulas in 7 (16%), and persisting active fistulas in 4 (9%) patients. CONCLUSIONS: Initial LIFT had a success rate of 40% and with subsequent surgical treatment 75%. Recurrence after LIFT is related to the height of the internal fistula opening and is associated with diminished quality of life. Continence was not affected by initial LIFT.


Assuntos
Canal Anal/cirurgia , Ligadura/métodos , Fístula Retal/cirurgia , Adulto , Idoso , Incontinência Fecal/epidemiologia , Incontinência Fecal/etiologia , Feminino , Humanos , Ligadura/efeitos adversos , Masculino , Pessoa de Meia-Idade , Medidas de Resultados Relatados pelo Paciente , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/etiologia , Qualidade de Vida , Recidiva , Resultado do Tratamento , Adulto Jovem
10.
Med J Malaysia ; 74(1): 30-33, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30846659

RESUMO

PURPOSE: To determine the effects of ChromaGen blue filter lens in reading speed, accuracy and contrast sensitivity. METHODS: A cross-over, randomised study was carried out on 40 individuals (11 males and 29 females) aged 21 to 30 years. The rate of reading and reading accuracy was calculated with and without ChromaGen blue filter lens in all subjects. Wilkins Rate of Reading Test was used to measure the rate of reading and reading accuracy. Contrast sensitivity was also evaluated by using with and without the ChromaGen blue filter lens. RESULTS: The mean rate of reading with and without ChromaGen blue filter lens was 160.58±16.03 words per minute and 150.52±15.66 words per minute respectively, with significant difference of p<0.001. The mean of reading accuracy (words correctly read per minute) in subjects, with ChromaGen blue filter was 149.30±0.79 words and without using filter lens was 148.53±1.11 words and found to be significant (p<0.001). There was no significant difference in the contrast sensitivity between subjects with and without the ChromaGen blue filter lens (p=0.083). No significant correlation was noted between the reading speed with age, spherical equivalent, contrast sensitivity, and reading accuracy. CONCLUSION: This study concludes that there was an increase of 6.68% in the rate of reading and improvement of 0.52% in accuracy among subjects with ChromaGen blue filter lens.


Assuntos
Lentes de Contato , Sensibilidades de Contraste , Leitura , Adulto , Estudos Cross-Over , Feminino , Humanos , Masculino , Acuidade Visual , Adulto Jovem
11.
Phys Rev Lett ; 120(24): 245003, 2018 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-29956968

RESUMO

A series of cryogenic, layered deuterium-tritium (DT) implosions have produced, for the first time, fusion energy output twice the peak kinetic energy of the imploding shell. These experiments at the National Ignition Facility utilized high density carbon ablators with a three-shock laser pulse (1.5 MJ in 7.5 ns) to irradiate low gas-filled (0.3 mg/cc of helium) bare depleted uranium hohlraums, resulting in a peak hohlraum radiative temperature ∼290 eV. The imploding shell, composed of the nonablated high density carbon and the DT cryogenic layer, is, thus, driven to velocity on the order of 380 km/s resulting in a peak kinetic energy of ∼21 kJ, which once stagnated produced a total DT neutron yield of 1.9×10^{16} (shot N170827) corresponding to an output fusion energy of 54 kJ. Time dependent low mode asymmetries that limited further progress of implosions have now been controlled, leading to an increased compression of the hot spot. It resulted in hot spot areal density (ρr∼0.3 g/cm^{2}) and stagnation pressure (∼360 Gbar) never before achieved in a laboratory experiment.

12.
Phys Rev Lett ; 118(24): 242002, 2017 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-28665642

RESUMO

We report the first beam-target double-polarization asymmetries in the γ+n(p)→π^{-}+p(p) reaction spanning the nucleon resonance region from invariant mass W=1500 to 2300 MeV. Circularly polarized photons and longitudinally polarized deuterons in solid hydrogen deuteride (HD) have been used with the CEBAF Large Acceptance Spectrometer (CLAS) at Jefferson Lab. The exclusive final state has been extracted using three very different analyses that show excellent agreement, and these have been used to deduce the E polarization observable for an effective neutron target. These results have been incorporated into new partial wave analyses and have led to significant revisions for several γnN^{*} resonance photocouplings.

13.
Spinal Cord ; 55(11): 994-1001, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28631745

RESUMO

STUDY DESIGN: A retrospective audit of assessor accuracy using the International Standards for Neurological Classification of Spinal Cord Injury (ISNCSCI) in three multicentre randomised controlled trials (SCIPA: Spinal Cord Injury and Physical Activity) spanning 2010-2014 with standards revised in 2011. OBJECTIVES: To investigate assessor accuracy of neurological classification after spinal cord injury. SETTING: Australia and New Zealand. METHODS: ISNCSCI examinations were undertaken by trained clinicians prior to randomisation. Data were recorded manually and ISNCSCI worksheets circulated to panels, consensus reached and worksheets corrected. An audit team used a 2014 computerised ISNCSCI algorithm to check manual worksheets. A second audit team assessed whether the 2014 computerised algorithm accurately reflected pre- and post-2011 ISNCSCI standards. RESULTS: Of the 208 ISNCSCI worksheets, 24 were excluded. Of the remaining 184 worksheets, 47 (25.5%) were consistent with the 2014 computerised algorithm and 137 (74.5%) contained one or more errors. Errors were in motor (30.1%) or sensory (12.4%) levels, zone of partial preservation (24.0%), motor/sensory scoring (21.5%), ASIA Impairment Scale (AIS, 8.3%) and complete/incomplete classification (0.8%). Other difficulties included classification when anal contraction/sensation was omitted, incorrect neurological levels and violation of the 'motor follows sensory rule in non-testable myotomes' (7.4%). Panel errors comprised corrections that were incorrect or missed or incorrect changes to correct worksheets. CONCLUSION: Given inaccuracies in the manual ISNCSCI worksheets in this long-term clinical trial setting, continued training and a computerised algorithm are essential to ensure accurate scoring, scaling and classification of the ISNCSCI and confidence in clinical trials.


Assuntos
Traumatismos da Medula Espinal/classificação , Algoritmos , Austrália , Humanos , Auditoria Médica , Exame Neurológico/normas , Nova Zelândia , Estudos Retrospectivos
14.
Hong Kong Med J ; 23(2): 191-201, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28387202

RESUMO

INTRODUCTION: In Hong Kong, the prevalence of atherosclerotic cardiovascular disease has increased markedly over the past few decades, and further increases are expected. In 2008, the Hong Kong Cardiovascular Task Force released a consensus statement on preventing cardiovascular disease in the Hong Kong population. The present article provides an update on these recommendations. PARTICIPANTS: A multidisciplinary group of clinicians comprising the Hong Kong Cardiovascular Task Force-10 cardiologists, an endocrinologist, and a family physician-met in September 2014 and June 2015 in Hong Kong. EVIDENCE: Guidelines from the American College of Cardiology/American Heart Association, the European Society of Hypertension/European Society of Cardiology, and the Eighth Joint National Committee for the Management of High Blood Pressure were reviewed. CONSENSUS PROCESS: Group members reviewed the 2008 Consensus Statement and relevant international guidelines. At the meetings, each topical recommendation of the 2008 Statement was assessed against the pooled recommendations on that topic from the international guidelines. A final recommendation on each topic was generated by consensus after discussion. CONCLUSIONS: It is recommended that a formal risk scoring system should be used for risk assessment of all adults aged 40 years or older who have at least one cardiovascular risk factor. Individuals can be classified as having a low, moderate, or high risk of developing atherosclerotic cardiovascular disease, and appropriate interventions selected accordingly. Recommended lifestyle modifications include adopting a healthy eating pattern; maintaining a low body mass index; quitting smoking; and undertaking regular, moderate-intensity physical activity. Pharmacological interventions should be selected as appropriate after lifestyle modification.


Assuntos
Anti-Hipertensivos/uso terapêutico , Aterosclerose/prevenção & controle , Doenças Cardiovasculares/prevenção & controle , Hipolipemiantes/uso terapêutico , Estilo de Vida , Adulto , Comitês Consultivos , Idoso , Idoso de 80 Anos ou mais , Aterosclerose/tratamento farmacológico , Pressão Sanguínea , Doenças Cardiovasculares/tratamento farmacológico , Feminino , Hong Kong , Humanos , Hipertensão/tratamento farmacológico , Hipertensão/prevenção & controle , Masculino , Pessoa de Meia-Idade , Medição de Risco , Fatores de Risco
15.
N Engl J Med ; 368(14): 1291-1302, 2013 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-23550668

RESUMO

BACKGROUND: Combination antifungal therapy (amphotericin B deoxycholate and flucytosine) is the recommended treatment for cryptococcal meningitis but has not been shown to reduce mortality, as compared with amphotericin B alone. We performed a randomized, controlled trial to determine whether combining flucytosine or high-dose fluconazole with high-dose amphotericin B improved survival at 14 and 70 days. METHODS: We conducted a randomized, three-group, open-label trial of induction therapy for cryptococcal meningitis in patients with human immunodeficiency virus infection. All patients received amphotericin B at a dose of 1 mg per kilogram of body weight per day; patients in group 1 were treated for 4 weeks, and those in groups 2 and 3 for 2 weeks. Patients in group 2 concurrently received flucytosine at a dose of 100 mg per kilogram per day for 2 weeks, and those in group 3 concurrently received fluconazole at a dose of 400 mg twice daily for 2 weeks. RESULTS: A total of 299 patients were enrolled. Fewer deaths occurred by days 14 and 70 among patients receiving amphotericin B and flucytosine than among those receiving amphotericin B alone (15 vs. 25 deaths by day 14; hazard ratio, 0.57; 95% confidence interval [CI], 0.30 to 1.08; unadjusted P=0.08; and 30 vs. 44 deaths by day 70; hazard ratio, 0.61; 95% CI, 0.39 to 0.97; unadjusted P=0.04). Combination therapy with fluconazole had no significant effect on survival, as compared with monotherapy (hazard ratio for death by 14 days, 0.78; 95% CI, 0.44 to 1.41; P=0.42; hazard ratio for death by 70 days, 0.71; 95% CI, 0.45 to 1.11; P=0.13). Amphotericin B plus flucytosine was associated with significantly increased rates of yeast clearance from cerebrospinal fluid (-0.42 log10 colony-forming units [CFU] per milliliter per day vs. -0.31 and -0.32 log10 CFU per milliliter per day in groups 1 and 3, respectively; P<0.001 for both comparisons). Rates of adverse events were similar in all groups, although neutropenia was more frequent in patients receiving a combination therapy. CONCLUSIONS: Amphotericin B plus flucytosine, as compared with amphotericin B alone, is associated with improved survival among patients with cryptococcal meningitis. A survival benefit of amphotericin B plus fluconazole was not found. (Funded by the Wellcome Trust and the British Infection Society; Controlled-Trials.com number, ISRCTN95123928.).


Assuntos
Anfotericina B/uso terapêutico , Antifúngicos/uso terapêutico , Flucitosina/uso terapêutico , Meningite Criptocócica/tratamento farmacológico , Adulto , Anfotericina B/efeitos adversos , Antifúngicos/efeitos adversos , Quimioterapia Combinada , Feminino , Flucitosina/efeitos adversos , Humanos , Quimioterapia de Indução , Estimativa de Kaplan-Meier , Masculino , Meningite Criptocócica/mortalidade
16.
Opt Express ; 24(23): 26667-26677, 2016 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-27857397

RESUMO

We demonstrate highly germania doped fibers for mid-infrared supercontinuum generation. Experiments ensure a highest output power of 1.44 W for a broadest spectrum from 700 nm to 3200 nm and 6.4 W for 800 nm to 2700 nm from these fibers, while being pumped by a broadband Erbium-Ytterbium doped fiber based master oscillator power amplifier. The effect of repetition frequency of pump source and length of germania-doped fiber has also been investigated. Further, germania doped fiber has been pumped by conventional supercontinuum source based on silica photonic crystal fiber supercontinuum source. At low power, a considerable broadening of 200-300 nm was observed. Further broadening of spectrum was limited due to limited power of pump source. Our investigations reveal the unexploited potential of germania doped fiber for mid-infrared supercontinuum generation. These measurements ensure the potential of germania based photonic crystal fiber or a step-index fiber supercontinuum source for high power ultra-broad band emission being by pumped a 1060 nm or a 1550 nm laser source. To the best of our knowledge, this is the record power, ultra-broadband, and all-fiberized supercontinuum light source based on silica and germania fiber ever demonstrated to the date.

17.
Osteoporos Int ; 27(5): 1747-54, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-26659066

RESUMO

UNLABELLED: The study aimed to prospectively evaluate if serum calcium is related to diabetes incidence in Hong Kong Chinese. The results showed that serum calcium has a significant association with increased risk of diabetes. The result of meta-analysis reinforced our findings. INTRODUCTION: This study aimed to evaluate the association of serum calcium, including serum total calcium and albumin-corrected calcium, with incident diabetes in Hong Kong Chinese. METHODS: We conducted a retrospective cohort study in 6096 participants aged 20 or above and free of diabetes at baseline. Serum calcium was measured at baseline. Incident diabetes was determined from several electronic databases. We also searched relevant databases for studies on serum calcium and incident diabetes and conducted a meta-analysis using fixed-effect modeling. RESULTS: During 59,130.9 person-years of follow-up, 631 participants developed diabetes. Serum total calcium and albumin-corrected calcium were associated with incident diabetes in the unadjusted model. After adjusting for demographic and clinical variables, the association remained significant only for serum total calcium (hazard ratio (HR), 1.32 (95 % confidence interval (CI), 1.02-1.70), highest vs. lowest quartile). In a meta-analysis of four studies including the current study, both serum total calcium (pooled risk ratio (RR), 1.38 (95 % CI, 1.15-1.65); I (2) = 5 %, comparing extreme quantiles) and albumin-corrected calcium (pooled RR, 1.29 (95 % CI, 1.03-1.61); I (2) = 0 %, comparing extreme quantiles) were associated with incident diabetes. Penalized regression splines showed that the association of incident diabetes with serum total calcium and albumin-correlated calcium was non-linear and linear, respectively. CONCLUSIONS: Elevated serum calcium concentration is associated with incident diabetes. The mechanism underlying this association warrants further investigation.


Assuntos
Cálcio/sangue , Diabetes Mellitus Tipo 2/sangue , Adulto , Idoso , Idoso de 80 Anos ou mais , Diabetes Mellitus Tipo 2/epidemiologia , Hong Kong/epidemiologia , Humanos , Incidência , Pessoa de Meia-Idade , Estudos Observacionais como Assunto , Estudos Retrospectivos , Fatores de Risco , Albumina Sérica/análise , Adulto Jovem
18.
J Virol ; 88(23): 13910-7, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25231299

RESUMO

Extending our previous analyses to the most recently described monoclonal broadly neutralizing antibodies (bNAbs), we confirmed a drift of HIV-1 clade B variants over 2 decades toward higher resistance to bNAbs targeting almost all the identified gp120-neutralizing epitopes. In contrast, the sensitivity to bNAbs targeting the gp41 membrane-proximal external region remained stable, suggesting a selective pressure on gp120 preferentially. Despite this evolution, selected combinations of bNAbs remain capable of neutralizing efficiently most of the circulating variants.


Assuntos
Anticorpos Monoclonais/imunologia , Anticorpos Neutralizantes/imunologia , Deriva Genética , Anticorpos Anti-HIV/imunologia , Proteína gp120 do Envelope de HIV/imunologia , Infecções por HIV/imunologia , HIV-1/imunologia , Animais , Epidemias , Proteína gp120 do Envelope de HIV/genética , Proteína gp41 do Envelope de HIV/genética , Proteína gp41 do Envelope de HIV/imunologia , Infecções por HIV/epidemiologia , Infecções por HIV/virologia , HIV-1/genética , HIV-1/isolamento & purificação , Humanos , Masculino , Camundongos , Testes de Neutralização
19.
Phys Rev Lett ; 114(17): 175001, 2015 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-25978240

RESUMO

Recent experiments on the National Ignition Facility [M. J. Edwards et al., Phys. Plasmas 20, 070501 (2013)] demonstrate that utilizing a near-vacuum hohlraum (low pressure gas-filled) is a viable option for high convergence cryogenic deuterium-tritium (DT) layered capsule implosions. This is made possible by using a dense ablator (high-density carbon), which shortens the drive duration needed to achieve high convergence: a measured 40% higher hohlraum efficiency than typical gas-filled hohlraums, which requires less laser energy going into the hohlraum, and an observed better symmetry control than anticipated by standard hydrodynamics simulations. The first series of near-vacuum hohlraum experiments culminated in a 6.8 ns, 1.2 MJ laser pulse driving a 2-shock, high adiabat (α∼3.5) cryogenic DT layered high density carbon capsule. This resulted in one of the best performances so far on the NIF relative to laser energy, with a measured primary neutron yield of 1.8×10(15) neutrons, with 20% calculated alpha heating at convergence ∼27×.

20.
Transpl Infect Dis ; 17(1): 89-93, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25573597

RESUMO

Legionella micdadei is a potential cause of invasive lung infections in immunocompromised hosts. On biopsy specimens, it can appear as an acid-fast bacillus (AFB) and can be mistaken for a member of genus Mycobacterium. As Legionella requires selective media to grow in culture, and the commonly used, commercially available urine antigen test for Legionella only detects Legionella pneumophila serogroup-1, but not L. micdadei, it is important to consider this organism in the differential diagnosis for AFB in immunocompromised hosts. We report a case of L. micdadei infection, which was initially treated empirically for non-tuberculous mycobacteria based on AFB staining of biopsy tissue before the final diagnosis was made.


Assuntos
Antígenos de Bactérias/imunologia , Transplante de Células-Tronco Hematopoéticas , Hospedeiro Imunocomprometido/imunologia , Legionella/isolamento & purificação , Legionelose/diagnóstico , Pneumopatias/diagnóstico , Idoso , Biópsia , Diagnóstico Diferencial , Evolução Fatal , Humanos , Legionella/imunologia , Legionelose/microbiologia , Legionelose/cirurgia , Pneumopatias/microbiologia , Pneumopatias/cirurgia , Masculino , Tomografia Computadorizada por Raios X
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