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1.
Nature ; 565(7741): 581-586, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30700868

RESUMO

Focusing laser light onto a very small target can produce the conditions for laboratory-scale nuclear fusion of hydrogen isotopes. The lack of accurate predictive models, which are essential for the design of high-performance laser-fusion experiments, is a major obstacle to achieving thermonuclear ignition. Here we report a statistical approach that was used to design and quantitatively predict the results of implosions of solid deuterium-tritium targets carried out with the 30-kilojoule OMEGA laser system, leading to tripling of the fusion yield to its highest value so far for direct-drive laser fusion. When scaled to the laser energies of the National Ignition Facility (1.9 megajoules), these targets are predicted to produce a fusion energy output of about 500 kilojoules-several times larger than the fusion yields currently achieved at that facility. This approach could guide the exploration of the vast parameter space of thermonuclear ignition conditions and enhance our understanding of laser-fusion physics.

2.
Phys Rev Lett ; 131(10): 105101, 2023 Sep 08.
Artigo em Inglês | MEDLINE | ID: mdl-37739360

RESUMO

In direct-drive inertial confinement fusion, the laser bandwidth reduces the laser imprinting seed of hydrodynamic instabilities. The impact of varying bandwidth on the performance of direct-drive DT-layered implosions was studied in targets with different hydrodynamic stability properties. The stability was controlled by changing the shell adiabat from (α_{F}≃5) (more stable) to (α_{F}≃3.5) (less stable). These experiments show that the performance of lower adiabat implosions improves considerably as the bandwidth is raised indicating that further bandwidth increases, beyond the current capabilities of OMEGA, would be greatly beneficial. These results suggest that the future generation of ultra-broadband lasers could enable achieving high convergence and possibly high gains in direct drive ICF.

3.
Ultrasound Obstet Gynecol ; 61(2): 207-214, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36722427

RESUMO

OBJECTIVE: Bariatric surgery is a successful treatment for sustainable weight loss and has been associated with improvement in cardiovascular function. Pregnancy after bariatric surgery is becoming increasingly common; however, little is known about the maternal cardiovascular system postsurgery. The aim of this study was to investigate maternal cardiovascular adaptation to pregnancy in women with previous bariatric surgery, compared with that in women with no history of weight-loss surgery and an early-pregnancy body mass index (BMI) similar to the presurgery BMI of the postbariatric women. METHODS: This was a prospective, observational, longitudinal study conducted from April 2018 to June 2020 including 30 pregnant women who had undergone bariatric surgery and 30 who had not, matched for presurgery BMI. Participants were seen at three timepoints during pregnancy: 12-14, 20-24 and 30-32 weeks' gestation. At all visits, maternal blood pressure (BP) was measured and cardiac geometry and function were assessed using two-dimensional (2D) transthoracic echocardiography. On a subset of patients (15 in each group), 2D speckle tracking was performed to assess global longitudinal and circumferential strain. Offline analysis was performed, and multilevel linear mixed-effects models were used for all comparisons. RESULTS: Compared with the no-surgery group, and across all trimesters, pregnant women with previous bariatric surgery had lower BP, heart rate and cardiac output and higher peripheral vascular resistance (P < 0.01 for all). Similarly, the postbariatric group demonstrated more favorable cardiac geometry and diastolic indices, including lower left ventricular mass, left atrial volume and relative wall thickness, together with higher E-wave/A-wave flow velocity across the mitral valve and higher mitral velocity (E') at the lateral and medial annulus on tissue Doppler imaging (P < 0.01 for all). There was no difference in ejection fraction, although global longitudinal strain was lower in postbariatric women (P < 0.01), indicating better systolic function. CONCLUSION: Our findings indicate better maternal cardiovascular adaptation in women with previous bariatric surgery compared with presurgery BMI-matched pregnant women with no history of weight-loss surgery. © 2022 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology.


Assuntos
Cirurgia Bariátrica , Sistema Cardiovascular , Gravidez , Feminino , Humanos , Estudos Longitudinais , Estudos Prospectivos , Valva Mitral
4.
Occup Med (Lond) ; 73(3): 155-160, 2023 04 26.
Artigo em Inglês | MEDLINE | ID: mdl-36893355

RESUMO

BACKGROUND: Diplomatic personnel frequently relocate as part of their roles, requiring them to adapt to various cultural and political conditions; many are also at risk of experiencing trauma from being deployed to high-threat postings. With diplomatic personnel having to balance the usual pressures of their work with the uncertainties of COVID-19 in recent years, it is particularly important now to understand how to protect their mental health. AIMS: To synthesize existing literature on the well-being of diplomatic personnel to improve understanding of how to protect their mental health. METHODS: A scoping review was carried out to explore what is already known about the well-being of staff working in diplomatic roles. Four databases were searched and reference lists, as well as one key journal, were hand-searched. RESULTS: Fifteen relevant publications were included. There was little consensus as to how the psychological well-being of diplomatic personnel compares to other populations or which factors predict well-being. Diplomats' psychological responses to traumatic experiences appeared similar to those of other trauma-exposed occupational groups. CONCLUSIONS: Further research is needed to better understand the well-being of diplomatic personnel, particularly those not deployed to high-threat posts.


Assuntos
COVID-19 , Saúde Mental , Humanos , Empregados do Governo , Pessoal de Saúde/psicologia
5.
Georgian Med News ; (339): 117-122, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37522786

RESUMO

This study aims to characterize and contrast the triennial rates at which doctors prescribe PT, determine patient, doctor, and practicing characteristics related to every therapy suggestion, and assess pain relievers, lifestyle counseling, and PT as effective treatments for knee osteoarthritis (OA). We analyzed the National Ambulatory Medical Care Survey. Nonsteroidal anti-inflammatory drugs (NSAID), narcotics prescriptions, physical therapy referrals, and primary care physician visits for knee OA have been determined and evaluated. The average yearly rate after three years of therapy was determined. Using multivariable logistic modeling with adjustments for complicated sample design, we analyzed the relationships among patient, physician, and practice characteristics and treatments. Over time the patients were prescribed physical therapy to improve their lifestyle whereas the percentage of patients who were prescribed NSAIDs or drugs. Physical therapy, lifestyle therapy, and drugs were prescribed at similar rates across time for basic care doctor visits. There was an association between nonclinical characteristics and treatment suggestions, such as provider type, practice setting, and geographic proximity. Physical therapy (PT) and lifestyle counseling (LC) seem underused in patients with knee OA, but prescriptions for pain medication rose over the studied period. The treatment decisions varied due to variables outside of medicine. Increased usage of physical therapy and lifestyle changes, as well as decreased treatment variance for knee OA, are important areas for further study.


Assuntos
Osteoartrite do Joelho , Manejo da Dor , Humanos , Dor , Acetaminofen , Estilo de Vida , Anti-Inflamatórios não Esteroides/uso terapêutico , Osteoartrite do Joelho/tratamento farmacológico
6.
Georgian Med News ; (339): 137-142, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37522789

RESUMO

Regular exercise helps to enhance health outcomes and lower risk factors, making it a crucial element in the prevention of chronic diseases. By being physically active, people can improve their general health and delay the onset of a number of chronic illnesses. For understanding the relationship between increased physical activity or decreased physical inactivity and favorable health outcomes, observational studies are the main source of information. We will look for systematic analyses of randomized controlled trials with a main emphasis on outcomes linked to diseases in the Cochrane Database of systematic studies. Evaluation will be limited to those in a few key chronic conditions. Preventing chronic illness and achieving better results in the management or treatment of chronic illness are the main outcomes of interest. For each chronic condition (such as the control of glucose in diabetes or any change in hypertension blood pressure), these results will be summarized and displayed. The design and implementation of chronic conditions, physical exercise illness conditions, and adverse physical activity-related events are of secondary interest. Our findings should help decision-makers, guideline organizations, and academics identify the most effective physical activity programs for major chronic disease management and prevention. Exercise and physical activity (PA) offers a non-invasive approach to the management of chronic disorders. More physiological, biochemical, and molecular data on the positive effects of PA and exercise on health should constitute a primary focus of future studies.


Assuntos
Exercício Físico , Hipertensão , Humanos , Doença Crônica , Pressão Sanguínea , Hipertensão/prevenção & controle , Fatores de Risco
7.
Mol Psychiatry ; 26(9): 5371-5388, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-33526823

RESUMO

Schizophrenia (Sz) is a highly polygenic disorder, with common, rare, and structural variants each contributing only a small fraction of overall disease risk. Thus, there is a need to identify downstream points of convergence that can be targeted with therapeutics. Reduction of microtubule-associated protein 2 (MAP2) immunoreactivity (MAP2-IR) is present in individuals with Sz, despite no change in MAP2 protein levels. MAP2 is phosphorylated downstream of multiple receptors and kinases identified as Sz risk genes, altering its immunoreactivity and function. Using an unbiased phosphoproteomics approach, we quantified 18 MAP2 phosphopeptides, 9 of which were significantly altered in Sz subjects. Network analysis grouped MAP2 phosphopeptides into three modules, each with a distinct relationship to dendritic spine loss, synaptic protein levels, and clinical function in Sz subjects. We then investigated the most hyperphosphorylated site in Sz, phosphoserine1782 (pS1782). Computational modeling predicted phosphorylation of S1782 reduces binding of MAP2 to microtubules, which was confirmed experimentally. We generated a transgenic mouse containing a phosphomimetic mutation at S1782 (S1782E) and found reductions in basilar dendritic length and complexity along with reduced spine density. Because only a limited number of MAP2 interacting proteins have been previously identified, we combined co-immunoprecipitation with mass spectrometry to characterize the MAP2 interactome in mouse brain. The MAP2 interactome was enriched for proteins involved in protein translation. These associations were shown to be functional as overexpression of wild type and phosphomimetic MAP2 reduced protein synthesis in vitro. Finally, we found that Sz subjects with low MAP2-IR had reductions in the levels of synaptic proteins relative to nonpsychiatric control (NPC) subjects and to Sz subjects with normal and MAP2-IR, and this same pattern was recapitulated in S1782E mice. These findings suggest a new conceptual framework for Sz-that a large proportion of individuals have a "MAP2opathy"-in which MAP function is altered by phosphorylation, leading to impairments of neuronal structure, synaptic protein synthesis, and function.


Assuntos
Esquizofrenia , Animais , Camundongos , Proteínas Associadas aos Microtúbulos/genética , Proteínas Associadas aos Microtúbulos/metabolismo , Microtúbulos/metabolismo , Neurônios/metabolismo , Fosforilação , Esquizofrenia/genética , Esquizofrenia/metabolismo
8.
BMC Nephrol ; 23(1): 9, 2022 01 03.
Artigo em Inglês | MEDLINE | ID: mdl-34979961

RESUMO

People with type 1 and type 2 diabetes are at risk of developing progressive chronic kidney disease (CKD) and end-stage kidney failure. Hypertension is a major, reversible risk factor in people with diabetes for development of albuminuria, impaired kidney function, end-stage kidney disease and cardiovascular disease. Blood pressure control has been shown to be beneficial in people with diabetes in slowing progression of kidney disease and reducing cardiovascular events. However, randomised controlled trial evidence differs in type 1 and type 2 diabetes and different stages of CKD in terms of target blood pressure. Activation of the renin-angiotensin-aldosterone system (RAAS) is an important mechanism for the development and progression of CKD and cardiovascular disease. Randomised trials demonstrate that RAAS blockade is effective in preventing/ slowing progression of CKD and reducing cardiovascular events in people with type 1 and type 2 diabetes, albeit differently according to the stage of CKD. Emerging therapy with sodium glucose cotransporter-2 (SGLT-2) inhibitors, non-steroidal selective mineralocorticoid antagonists and endothelin-A receptor antagonists have been shown in randomised trials to lower blood pressure and further reduce the risk of progression of CKD and cardiovascular disease in people with type 2 diabetes. This guideline reviews the current evidence and makes recommendations about blood pressure control and the use of RAAS-blocking agents in different stages of CKD in people with both type 1 and type 2 diabetes.


Assuntos
Anti-Hipertensivos/uso terapêutico , Angiopatias Diabéticas/tratamento farmacológico , Nefropatias Diabéticas/tratamento farmacológico , Hipertensão/tratamento farmacológico , Sistema Renina-Angiotensina/efeitos dos fármacos , Adulto , Albuminúria , Monitorização Ambulatorial da Pressão Arterial , Diabetes Mellitus Tipo 1/complicações , Diabetes Mellitus Tipo 2/complicações , Angiopatias Diabéticas/fisiopatologia , Angiopatias Diabéticas/urina , Nefropatias Diabéticas/fisiopatologia , Nefropatias Diabéticas/urina , Humanos , Hipertensão/fisiopatologia , Hipertensão/urina , Cooperação do Paciente , Comportamento de Redução do Risco , Reino Unido
9.
J Assoc Physicians India ; 70(4): 11-12, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35443409

RESUMO

ICH is one of the most serious neurological emergency which can result in high mortality which may be related to catecholamine release. We aim to evaluate serum catecholamine levels in acute ICH and correlate their levels with clinical parameters of stress and outcome. MATERIAL: Consecutive patients with CT proven ICH within 7 days of ictus were included and their clinical finding, SIRS Parameters, GCS, NIH score, laboratory parameters (ESR, CRP) were evaluated. Serum Catecholamine (DA, NE, E) levels were measured by LCMS. The patients were followed up at discharge and one month, the outcome was defined by mortality and 1 month modified Rankin scale (good 0-2, poor >2). OBSERVATION: There were 31 patients of acute ICH. Patients were admitted 1 to 2 days after ictus. Among the patients 19 were male and 12 were female.Their age ranged from 31 to 86 with mean 53.3+- 16.7. History of hypertension was present in 27.3% of patients. Their average GCS was median 12 (6.0, 15.0) and NIHSS was 12.5 (8.5, 22) Their average ESR was 30 (13,56) and average CRP was 1.8 (1.1, 5.9). Almost all pateints had raised SIRS parameters. There was an increase in levels of Dopamine (63.2 pg/ml), Epinephrine (73.5 pg/ml) and Norepinephrine (390pg/ml) on admission as compared to their levels 1 week after ictus or on discharge (Dopamine 35.6, Epinephrine 52.1, and Norepinephrine 241 pg/ml). CONCLUSION: CA surge is common in ICH pateints and it correlates with severity and outcome of patient. 6 pateints died in the hospital 72 % of patients had poor outcome. Catecholamine levels were higher in poor outcome patients.


Assuntos
Dopamina , Acidente Vascular Cerebral , Catecolaminas , Hemorragia Cerebral , Epinefrina , Feminino , Humanos , Masculino , Norepinefrina , Prognóstico , Síndrome de Resposta Inflamatória Sistêmica
10.
HIV Med ; 22(1): 28-36, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-32964664

RESUMO

OBJECTIVES: We aimed to compare the effectiveness of antiretroviral therapy (ART) classes for achieving HIV RNA suppression to < 50 HIV-1 RNA copies/mL within 6 months of initiation with high viral loads (VLs). Secondary objectives were to compare viral suppression (VS) at 12 weeks and 12 months, partial HIV RNA suppression to < 200 copies/mL, time to VS, time to rebound, and change in CD4 cell count. METHODS: This was a multicentre, retrospective, observational study. Adult patients were included if they initiated ART between January 2005 and December 2016 with a VL ≥ 100 000 copies/mL. RESULTS: There were 220 patients included in the study. The median VL was 252 919 [interquartile range (IQR) 149 472-500 000] copies/mL. Nonnucleoside reverse transcriptase inhibitor (NNRTI) recipients were more likely to achieve VS by 6 months compared to those initiating ART containing protease inhibitors (PIs) [75.4% vs. 44.1%, respectively; odds ratio (OR) 3.34; 95% confidence interval (CI) 1.62-6.90] or integrase strand transfer inhibitors (INSTIs) (75.4% vs. 55.8%, respectively; OR 2.40; 95% CI 1.03-5.58). VS at 12 weeks was more frequent with INSTI-containing regimens than with PIs (28.9% vs. 9.0%, respectively; OR 4.10; 95% CI 1.69-9.92). VS at 12 months did not significantly differ between treatment regimens. Median time to complete VS for INSTI, PI and NNRTI recipients was 22.3 (95% CI 13.4-33), 30.1 (95% CI 25-36) and 19.9 (95% CI 16-22.3) weeks, respectively. There were no significant differences in time to viral rebound or change in CD4 cell counts. CONCLUSIONS: Patients with high VLs initiated on NNRTIs were more likely to achieve VS by 6 months on ART compared to INSTI and PI recipients.


Assuntos
Infecções por HIV/tratamento farmacológico , Inibidores de Integrase de HIV/uso terapêutico , Inibidores da Transcriptase Reversa/uso terapêutico , Carga Viral/efeitos dos fármacos , Adulto , Terapia Antirretroviral de Alta Atividade , Feminino , Infecções por HIV/virologia , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Carga Viral/estatística & dados numéricos
11.
Phys Rev Lett ; 127(5): 055001, 2021 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-34397224

RESUMO

Hot electrons generated by laser-plasma instabilities degrade the performance of laser-fusion implosions by preheating the DT fuel and reducing core compression. The hot-electron energy deposition in the DT fuel has been directly measured for the first time by comparing the hard x-ray signals between DT-layered and mass-equivalent ablator-only implosions. The electron energy deposition profile in the fuel is inferred through dedicated experiments using Cu-doped payloads of varying thickness. The measured preheat energy accurately explains the areal-density degradation observed in many OMEGA implosions. This technique can be used to assess the viability of the direct-drive approach to laser fusion with respect to the scaling of hot-electron preheat with laser energy.

12.
Phys Rev Lett ; 127(10): 105001, 2021 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-34533333

RESUMO

Statistical modeling of experimental and simulation databases has enabled the development of an accurate predictive capability for deuterium-tritium layered cryogenic implosions at the OMEGA laser [V. Gopalaswamy et al.,Nature 565, 581 (2019)10.1038/s41586-019-0877-0]. In this letter, a physics-based statistical mapping framework is described and used to uncover the dependencies of the fusion yield. This model is used to identify and quantify the degradation mechanisms of the fusion yield in direct-drive implosions on OMEGA. The yield is found to be reduced by the ratio of laser beam to target radius, the asymmetry in inferred ion temperatures from the ℓ=1 mode, the time span over which tritium fuel has decayed, and parameters related to the implosion hydrodynamic stability. When adjusted for tritium decay and ℓ=1 mode, the highest yield in OMEGA cryogenic implosions is predicted to exceed 2×10^{14} fusion reactions.

13.
Appl Opt ; 60(19): D52-D72, 2021 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-34263828

RESUMO

Over the last decade, the vector-apodizing phase plate (vAPP) coronagraph has been developed from concept to on-sky application in many high-contrast imaging systems on 8 m class telescopes. The vAPP is a geometric-phase patterned coronagraph that is inherently broadband, and its manufacturing is enabled only by direct-write technology for liquid-crystal patterns. The vAPP generates two coronagraphic point spread functions (PSFs) that cancel starlight on opposite sides of the PSF and have opposite circular polarization states. The efficiency, that is, the amount of light in these PSFs, depends on the retardance offset from a half-wave of the liquid-crystal retarder. Using different liquid-crystal recipes to tune the retardance, different vAPPs operate with high efficiencies (${\gt}96\%$) in the visible and thermal infrared (0.55 µm to 5 µm). Since 2015, seven vAPPs have been installed in a total of six different instruments, including Magellan/MagAO, Magellan/MagAO-X, Subaru/SCExAO, and LBT/LMIRcam. Using two integral field spectrographs installed on the latter two instruments, these vAPPs can provide low-resolution spectra (${\rm{R}} \sim 30$) between 1 µm and 5 µm. We review the design process, development, commissioning, on-sky performance, and first scientific results of all commissioned vAPPs. We report on the lessons learned and conclude with perspectives for future developments and applications.

14.
Fish Physiol Biochem ; 47(3): 725-735, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32488550

RESUMO

Spotted wolffish Anarhichas minor reproduction in captivity is dependent on in vitro fertilization. However, it is often challenging to acquire sufficient fresh sperm to fertilize the eggs that are obtained. In this study, we evaluate the possibility to store spotted wolffish sperm by refrigeration. Spotted wolffish sperm has the particularity that is already motile on stripping, and currently it is not possible to immobilize and reactivate. Thus, sperm refrigeration protocols should focus in extending this motility period that usually lasts up to 2 days. In a first experiment, we evaluated the possibility that the motility period of the sperm was limited by contamination with urine. The urea concentration in the sperm obtained both by stripping (17.10 ± 1.98 mg/dL) and directly from the testis (12.59 ± 2.37 mg/dL) was similar (p > 0.05), which indicate that the sperm collection method used avoid contamination with urine. Afterwards, we tested the possibility that the sperm motility period was limited by energy stores. The ATP concentration (initial value 5.65 ± 0.86 nmol/109 cells) remained stable (p = 0.099) during 30 h after sperm collection, and similar values (p = 0.329) were recorded at end of sperm storage in both diluted (3.88 ± 1.35 nmol/109 cells) and undiluted samples (4.76 ± 1.08 nmol/109). This indicates that the low intracellular ATP consumption, derived from the slow sperm motility, can probably be compensated rapidly enough by mitochondrial synthesis of ATP in the spotted wolffish sperm. In both experiments, diluted sperm kept higher percentage of motile cells during the storage time.


Assuntos
Perciformes , Preservação do Sêmen/métodos , Trifosfato de Adenosina/metabolismo , Animais , Glucose/metabolismo , Masculino , Concentração Osmolar , Perciformes/urina , Proteínas/metabolismo , Refrigeração , Sêmen/metabolismo , Motilidade dos Espermatozoides , Espermatozoides , Ureia/metabolismo
15.
Eur J Prosthodont Restor Dent ; 29(2): 93-101, 2021 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-33393739

RESUMO

Toothwear is a growing concern, particularly in young adults. Prevention strategies remain of utmost importance and may involve the use of remineralising agents. If restorative treatment is indicated, adhesive techniques are recommended. It is unknown whether remineralising agents affect adhesion. METHOD: 77 bovine incisors were subjected to simulated toothwear by erosion (0.3% citric acid) and abrasion (oscillating toothbrush). Samples were randomly arranged into 5 test and 2 control groups (n=11). Each test group had a remineralising agent applied. Subsequently, composite was bonded to each sample and subjected to shear bond testing. Shear bond strength, mode of failure and enamel surface changes were analysed. RESULTS: There was no statistically significant difference for bond strength between groups (p=0.262). Mode of failure was statistically significant between groups (p⟨0.0001). Qualitative analysis showed a surface layer on samples remineralised by calcium silicate and stannous fluoride. Both groups had more adhesive failures. CONCLUSION: Within the limitations of this study, it can be concluded that the remineralising agents tested do not affect shear bond strength though surface layers created on the enamel influence the mode of failure. These 'sacrificial' surface layers have the potential to protect the underlying enamel structure.


Assuntos
Colagem Dentária , Desmineralização do Dente , Animais , Bovinos , Resinas Compostas , Cimentos Dentários , Esmalte Dentário , Análise do Estresse Dentário , Teste de Materiais , Cimentos de Resina , Resistência ao Cisalhamento
16.
Br J Dermatol ; 181(1): 88-95, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-30734266

RESUMO

BACKGROUND: Inhibiting interleukin (IL)-23 in patients with psoriasis has demonstrated high levels of skin clearance. OBJECTIVES: To investigate, in a phase II (AMAF; NCT02899988), multicentre, double-blind trial, the efficacy and safety of three doses of mirikizumab (LY3074828), a p19-directed IL-23 antibody, vs. placebo in patients with moderate-to-severe plaque psoriasis. METHODS: Adult patients were randomized 1 : 1 : 1 : 1 to receive placebo (n = 52), mirikizumab 30 mg (n = 51), mirikizumab 100 mg (n = 51) or mirikizumab 300 mg (n = 51) subcutaneously at weeks 0 and 8. The primary objective was to evaluate the superiority of mirikizumab over placebo in achieving a 90% improvement in the Psoriasis Area and Severity Index (PASI 90) response at week 16. Comparisons were done using logistic regression analysis with treatment, geographical region and previous biological therapy in the model. Missing data were imputed as nonresponses. RESULTS: Ninety-seven per cent of patients completed the first 16 weeks of the study. The primary end point was met for all mirikizumab dose groups vs. placebo, with PASI 90 response rates at week 16 of 0%, 29% (P = 0·009), 59% (P < 0·001) and 67% (P < 0·001) for patients receiving placebo, and mirikizumab 30 mg, 100 mg and 300 mg, respectively. There were two (1%) serious adverse events in mirikizumab-treated patients vs. one (2%) in a placebo-group patient. CONCLUSIONS: At week 16, 67% of patients treated with mirikizumab 300 mg at 8-week intervals achieved PASI 90. The percentage of patients reporting at least one treatment-emergent adverse event was similar among patients treated with placebo or mirikizumab.


Assuntos
Anti-Inflamatórios não Esteroides/administração & dosagem , Anticorpos Monoclonais Humanizados/administração & dosagem , Psoríase/tratamento farmacológico , Adulto , Idoso , Anti-Inflamatórios não Esteroides/efeitos adversos , Anticorpos Monoclonais Humanizados/efeitos adversos , Relação Dose-Resposta a Droga , Método Duplo-Cego , Esquema de Medicação , Feminino , Humanos , Injeções Subcutâneas , Subunidade p19 da Interleucina-23/antagonistas & inibidores , Subunidade p19 da Interleucina-23/imunologia , Masculino , Pessoa de Meia-Idade , Placebos/administração & dosagem , Placebos/efeitos adversos , Psoríase/diagnóstico , Psoríase/imunologia , Índice de Gravidade de Doença , Resultado do Tratamento , Adulto Jovem
17.
Public Health ; 168: 150-156, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30442468

RESUMO

OBJECTIVES: A routine review of hepatitis A travel vaccination recommendations was brought forward in June 2017 due to hepatitis A vaccine shortages and a concurrent outbreak in men who have sex with men (MSM). There were three objectives: first, to document the review process for changing the recommendations for the UK travellers in June 2017. Second, to study the impact of these changes on prescribing in general practice in 2017 compared with the previous 5 years. Third, to study any changes in hepatitis A notifications in June-October 2017 compared with the previous 5 years. STUDY DESIGN: This is an observational study. METHODS: Travel vaccination recommendations for countries with either low-risk (<20%) or high-risk (>90%) status according to child hepatitis A seroprevalence were not changed. A total of 67 intermediate-risk countries with existing recommendations for most travellers and with new data on rural sanitation levels were shortlisted for the analysis. Data on child hepatitis A seroprevalence, country income status, access to sanitation in rural areas and traveller volumes were obtained. Information about the vaccine supply was obtained from Public Health England. Changes to the existing classification were made through expert consensus, based on countries' hepatitis A seroprevalence, sanitation levels, level of income, volume of travel and hepatitis A traveller cases. Data on the number of combined and monovalent hepatitis A-containing vaccines prescribed in England, 2012-2017, were obtained from the National Health Service Business Service Authorities. The number of monthly prescriptions for January-September 2017 was compared with the mean number of prescriptions for the same month in the previous 5 years (t-test, α = 5%, df = 4). The number of hepatitis A cases notified in June-October 2017 not related to the MSM outbreak was compared with the number of notifications in the same months in previous years. RESULTS: A total of 36 countries were downgraded based on good access (80+% of population) to sanitation in rural areas and the intermediate-risk status in terms of child hepatitis A seroprevalence. For these countries, vaccination would only be recommended to travellers staying long term, visiting friends and relatives or staying in areas without good sanitation. There was a significant decline in hepatitis A vaccine prescriptions in June-September 2017, and there was no increase in the number of notifications. CONCLUSIONS: Hepatitis A vaccination recommendations for travel were revised in 2017 following a systematic approach to maintain continuity of supply after a hepatitis A vaccine shortage and increased hepatitis A vaccine demand related to a large outbreak. Improved access to good sanitation in rural areas and low seroprevalence estimates among children have led to 36 countries to no longer require vaccination for most travellers. These changes do not seem to have impacted on hepatitis A notifications in England, although further research will be needed to quantify the impact more precisely.


Assuntos
Política de Saúde , Vacinas contra Hepatite A/administração & dosagem , Vacinas contra Hepatite A/provisão & distribuição , Hepatite A/prevenção & controle , Viagem , Surtos de Doenças/prevenção & controle , Hepatite A/epidemiologia , Homossexualidade Masculina/estatística & dados numéricos , Humanos , Masculino , Guias de Prática Clínica como Assunto , Reino Unido/epidemiologia
18.
Clin Exp Allergy ; 48(10): 1275-1285, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-29900603

RESUMO

Whilst severe asthma has classically been categorized as a predominantly Th2-driven pathology, there has in recent years been a paradigm shift with the realization that it is a heterogeneous disease that may manifest with quite disparate underlying inflammatory and remodelling profiles. A subset of asthmatics, particularly those with a severe, corticosteroid refractory disease, present with a prominent neutrophilic component. Given the potential of neutrophils to impart extensive tissue damage and promote inflammation, it has been anticipated that these cells are closely implicated in the underlying pathophysiology of severe asthma. However, uncertainty persists as to why the neutrophil is present in the asthmatic lung and what precisely it is doing there, with evidence supporting its role as a protagonist of pathology being primarily circumstantial. Furthermore, our view of the neutrophil as a primitive, indiscriminate killer has evolved with the realization that neutrophils can exhibit a marked anti-inflammatory, pro-resolving and wound healing capacity. We suggest that the neutrophil likely exhibits pleiotropic and potentially conflicting roles in defining asthma pathophysiology-some almost certainly detrimental and some potentially beneficial-with context, timing and location all critical confounders. Accordingly, indiscriminate blockade of neutrophils with a broad sword approach is unlikely to be the answer, but rather we should first seek to understand their complex and multifaceted roles in the disease state and then target them with the same subtleties and specificity that they themselves exhibit.


Assuntos
Asma/etiologia , Suscetibilidade a Doenças , Neutrófilos/imunologia , Animais , Asma/metabolismo , Asma/patologia , Humanos , Imunomodulação , Infiltração de Neutrófilos/imunologia , Neutrófilos/metabolismo , Neutrófilos/patologia , Subpopulações de Linfócitos T/imunologia , Subpopulações de Linfócitos T/metabolismo
19.
Opt Express ; 26(24): 31222-31232, 2018 Nov 26.
Artigo em Inglês | MEDLINE | ID: mdl-30650711

RESUMO

We demonstrate the first simplified coherent receiver using a 120° hybrid on silicon-on-insulator (SOI) for high speed PON applications. This coherent receiver integrates an inverse taper edge coupler for the received signal, a vertical grating coupler for the local oscillator input, a polarization splitter and rotator (PSR), a 120° hybrid based on a 3×3 multimode interference (MMI) coupler, and three germanium photodetectors. We achieved 25 Gbit/s two-level pulse amplitude modulation (PAM-2) transmission over 30 km standard single mode fiber (SMF) in the C-band without any digital signal processing (DSP) (e.g., pre-emphasis, pulse shaping, equalization, nonlinearity compensation) and dispersion compensation (e.g., optical or digital) either at the transmitter or at the receiver. The requirements for frequency and phase locking of the local oscillator (LO) were avoided due to the use of intensity modulated signals. Receiver sensitivities of -23.70 dBm, -20.30 dBm, and -15.10 dBm are achieved at a bit error rate (BER) below the hard-decision forward error correction (HD-FEC) threshold (i.e., 3.8 × 10-3) in back-to-back (B2B), after 21 km and 30 km, respectively. We also demonstrate 25 Gbit/s PAM-4 transmission achieving receiver sensitivities of -15.30 dBm, -13.90 dBm, and -9.50 dBm below the HD-FEC threshold in B2B, after 10.5 km and 21 km, respectively.

20.
Br J Surg ; 105(12): 1680-1687, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-29974946

RESUMO

BACKGROUND: Surgical-site infection (SSI) is associated with significant healthcare costs. To reduce the high rate of SSI among patients undergoing colorectal surgery at a cancer centre, a comprehensive care bundle was implemented and its efficacy tested. METHODS: A pragmatic study involving three phases (baseline, implementation and sustainability) was conducted on patients treated consecutively between 2013 and 2016. The intervention included 13 components related to: bowel preparation; oral and intravenous antibiotic selection and administration; skin preparation, disinfection and hygiene; maintenance of normothermia during surgery; and use of clean instruments for closure. SSI risk was evaluated by means of a preoperative calculator, and effectiveness was assessed using interrupted time-series regression. RESULTS: In a population with a mean BMI of 30 kg/m2 , diabetes mellitus in 17·5 per cent, and smoking history in 49·3 per cent, SSI rates declined from 11·0 to 4·1 per cent following implementation of the intervention bundle (P = 0·001). The greatest reductions in SSI rates occurred in patients at intermediate or high risk of SSI: from 10·3 to 4·7 per cent (P = 0·006) and from 19 to 2 per cent (P < 0·001) respectively. Wound care modifications were very different in the implementation phase (43·2 versus 24·9 per cent baseline), including use of an overlying surface vacuum dressing (17·2 from 1·4 per cent baseline) or leaving wounds partially open (13·2 from 6·7 per cent baseline). As a result, the biggest difference was in wound-related rather than organ-space SSI. The median length of hospital stay decreased from 7 (i.q.r. 5-10) to 6 (5-9) days (P = 0·002). The greatest reduction in hospital stay was seen in patients at high risk of SSI: from 8 to 6 days (P < 0·001). SSI rates remained low (4·5 per cent) in the sustainability phase. CONCLUSION: Meaningful reductions in SSI can be achieved by implementing a multidisciplinary care bundle at a hospital-wide level.


Assuntos
Pacotes de Assistência ao Paciente/normas , Equipe de Assistência ao Paciente/normas , Infecção da Ferida Cirúrgica/prevenção & controle , Feminino , Humanos , Tempo de Internação/estatística & dados numéricos , Masculino , Pessoa de Meia-Idade , Readmissão do Paciente/estatística & dados numéricos , Fatores de Risco , Resultado do Tratamento , Técnicas de Fechamento de Ferimentos/normas
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