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1.
Nature ; 554(7693): 497-499, 2018 02 21.
Artigo em Inglês | MEDLINE | ID: mdl-29469097

RESUMO

It is difficult to establish the properties of massive stars that explode as supernovae. The electromagnetic emission during the first minutes to hours after the emergence of the shock from the stellar surface conveys important information about the final evolution and structure of the exploding star. However, the unpredictable nature of supernova events hinders the detection of this brief initial phase. Here we report the serendipitous discovery of a newly born, normal type IIb supernova (SN 2016gkg), which reveals a rapid brightening at optical wavelengths of about 40 magnitudes per day. The very frequent sampling of the observations allowed us to study in detail the outermost structure of the progenitor of the supernova and the physics of the emergence of the shock. We develop hydrodynamical models of the explosion that naturally account for the complete evolution of the supernova over distinct phases regulated by different physical processes. This result suggests that it is appropriate to decouple the treatment of the shock propagation from the unknown mechanism that triggers the explosion.

2.
J Chem Phys ; 160(6)2024 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-38341782

RESUMO

Poly(ethylene oxide) (PEO) is a well-known biocompatible polymer and has widely been used for medical applications. Recently, we have investigated the dynamic behavior of hydration water in the vicinity of PEO chains at physiological temperature and shown the presence of slow water with diffusion coefficient one order of magnitude less than that of bulk water. This could be evidence for the intermediate water that is critical for biocompatibility; however, its detailed dynamical features were not established. In this article, we analyze the quasi-elastic neutron scattering from hydration water through mode distribution analysis and present a microscopic picture of hydration water as well as its relation to cold crystallization.

3.
Nature ; 551(7678): 67-70, 2017 11 02.
Artigo em Inglês | MEDLINE | ID: mdl-29094694

RESUMO

The merger of two neutron stars is predicted to give rise to three major detectable phenomena: a short burst of γ-rays, a gravitational-wave signal, and a transient optical-near-infrared source powered by the synthesis of large amounts of very heavy elements via rapid neutron capture (the r-process). Such transients, named 'macronovae' or 'kilonovae', are believed to be centres of production of rare elements such as gold and platinum. The most compelling evidence so far for a kilonova was a very faint near-infrared rebrightening in the afterglow of a short γ-ray burst at redshift z = 0.356, although findings indicating bluer events have been reported. Here we report the spectral identification and describe the physical properties of a bright kilonova associated with the gravitational-wave source GW170817 and γ-ray burst GRB 170817A associated with a galaxy at a distance of 40 megaparsecs from Earth. Using a series of spectra from ground-based observatories covering the wavelength range from the ultraviolet to the near-infrared, we find that the kilonova is characterized by rapidly expanding ejecta with spectral features similar to those predicted by current models. The ejecta is optically thick early on, with a velocity of about 0.2 times light speed, and reaches a radius of about 50 astronomical units in only 1.5 days. As the ejecta expands, broad absorption-like lines appear on the spectral continuum, indicating atomic species produced by nucleosynthesis that occurs in the post-merger fast-moving dynamical ejecta and in two slower (0.05 times light speed) wind regions. Comparison with spectral models suggests that the merger ejected 0.03 to 0.05 solar masses of material, including high-opacity lanthanides.

4.
J Dairy Sci ; 106(10): 6710-6722, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37211485

RESUMO

Yogurt is made by fermenting milk with 2 lactic acid bacteria, Lactobacillus delbrueckii ssp. bulgaricus and Streptococcus thermophilus. To comprehensively understand the protocooperation mechanism between S. thermophilus and L. bulgaricus in yogurt fermentation, we examined 24 combinations of cocultures comprising 7 fast- or slow-acidifying S. thermophilus strains with 6 fast- or slow-acidifying L. bulgaricus strains. Furthermore, 3 NADH oxidase (Nox)-deficient mutants (Δnox) and one pyruvate formate-lyase deficient mutant (ΔpflB) of S. thermophilus were used to evaluate the factor that determines the acidification rate of S. thermophilus. The results revealed that the acidification rate of S. thermophilus monoculture determined the yogurt fermentation rates, despite the coexistence of L. bulgaricus, whose acidification rate was either fast or slow. Significant correlation was found between the acidification rate of S. thermophilus monoculture and the amount of formate production. Result using ΔpflB showed that the formate was indispensable for the acidification of S. thermophilus. Moreover, results of the Δnox experiments revealed that formate production required Nox activity, which not only regulated dissolved oxygen, but also the redox potential. The Nox provided the large decrease in redox potential required by pyruvate formate-lyase to produce formate. A highly significant correlation was found between formate accumulation and Nox activity in S. thermophilus. In conclusion, the formate production ability provided by the action of Nox activity determines the acidification rate of S. thermophilus, and consequently, regulates yogurt coculture fermentation.


Assuntos
Lactobacillus delbrueckii , Iogurte , Animais , Iogurte/microbiologia , Streptococcus thermophilus/fisiologia , NAD , Oxirredutases , Fermentação , Formiatos , Concentração de Íons de Hidrogênio
5.
Pharmazie ; 78(9): 212-215, 2023 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-38037214

RESUMO

To achieve appropriate blood pressure control in the treatment of hypertension in Japan, this study examined the relationship between office blood pressure and actual antihypertensive drug use in general hospitals following the promulgation of the guidelines for hypertension (JSH2019). This study focused on blood pressure levels and drug use in outpatients on antihypertensive treatment from June to July 2020. The subjects were 2,537 patients classified into four groups based on their medical history, patients with: hypertension only; hypertension and cardiovascular disease; hypertension and dyslipidaemia; and hypertension and diabetes mellitus. The results showed a significant difference in systolic blood pressure (SBP) between patients with hypertension only and those with hypertension and cardiovascular disease (138.3±17.9 mmHg vs 135.6±19.9 mmHg, p<0.05). Regarding actual drug use, it was found that diuretics were prescribed more frequently in patients with hypertension and cardiovascular disease than in those with hypertension alone (15.5% vs 37.9%, p<0.05), even though the number of drugs for hypertension did not differ significantly. In addition, the dose of diuretics was greater only in patients with cardiovascular disease. These results show the actual drug use and blood pressure for each comorbidity. Furthermore, they suggest that the results of antihypertensive treatment may differ by changing the combination and dosage of antihypertensive drugs without changing the number of antihypertensive drugs used. The study also shows the problem of using less diuretics depending on the risk the patient has, and solving the problem may lead to achieving further antihypertensive goals.


Assuntos
Doenças Cardiovasculares , Hipertensão , Humanos , Anti-Hipertensivos/uso terapêutico , Anti-Hipertensivos/farmacologia , Pressão Sanguínea , Doenças Cardiovasculares/induzido quimicamente , Hipertensão/tratamento farmacológico , Diuréticos/uso terapêutico
6.
Scand J Rheumatol ; 51(6): 431-440, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34511031

RESUMO

OBJECTIVE: Currently, biological disease-modifying anti-rheumatic drugs (bDMARDs) with different modes of action [tumour necrosis factor inhibitor (TNFi), interleukin-6 receptor inhibitor (IL-6Ri), or cytotoxic T-lymphocyte antigen 4-immunoglobulin (CTLA4-Ig)] are used in clinical practice to treat rheumatoid arthritis (RA). However, it is unclear which type of bDMARD is the most efficacious for a specific clinical situation. C-reactive protein (CRP) is an acute-phase reactant driven by IL-6 signalling. Here, we aimed to establish whether therapeutic efficacy differs between IL-6Ri and other bDMARDs with alternative modes of action in RA patients according to their CRP level. METHOD: RA patients treated with bDMARDs were enrolled from an observational multicentre registry in Japan. Patients were classified into three groups according to baseline CRP tertiles. The overall 3 year retention rates of each bDMARD category were assessed. The Clinical Disease Activity Index (CDAI) was also assessed before and 3, 6, and 12 months after bDMARD initiation. RESULTS: A total of 1438 RA patients were included and classified into three groups according to tertiles of baseline CRP levels (CRP1, 0-0.3; CRP2, 0.3-1.8; CRP3, 1.8-18.4 mg/dL). In CRP3, the overall 3 year drug retention rates were significantly higher for IL-6Ri than for TNFi and CTLA4-Ig (77.5 vs 48.2 vs 67.3, respectively). No significant difference was evident in terms of CDAI 12 months after bDMARD initiation in CRP1-CRP3. CONCLUSION: IL-6Ri may be a favourable therapeutic option over TNFi and CTLA4-Ig in RA patients with high CRP levels.


Assuntos
Antirreumáticos , Artrite Reumatoide , Humanos , Abatacepte/uso terapêutico , Estudos de Coortes , Artrite Reumatoide/tratamento farmacológico , Antirreumáticos/uso terapêutico , Inibidores do Fator de Necrose Tumoral , Anticorpos , Resultado do Tratamento
7.
AIDS Behav ; 26(2): 361-374, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34331608

RESUMO

Pre-exposure prophylaxis (PrEP) affords an opportunity to significantly reduce the risk of HIV infection among male couples. We used cross-sectional dyadic data from 382 concordant-negative male couples to examine demographic and relationship characteristics associated with current PrEP use, willingness to use PrEP in the future, and perceived ability to adhere to PrEP using Actor-Partner Independence Models. Few partnered men reported currently using PrEP (16.4%) and 57.7% of non-users reported being unlikely to use PrEP in the future. Actor and partner perceptions of PrEP stigma significantly reduced PrEP use and perceptions of willingness to use PrEP or the ability to adhere to PrEP, while perceiving a higher prevalence of HIV among men was associated with significant increases in PrEP use, willingness and perceived ability to adhere. Perceptions that more friends would support PrEP use were also significantly associated with increases in willingness and perceived ability to adhere to PrEP. Dyadic interventions are needed to provide couples the skills to communicate about HIV risk and prevention, and address myths around the protective effect of relationships against HIV acquisition.


Assuntos
Infecções por HIV , Profilaxia Pré-Exposição , Estudos Transversais , Infecções por HIV/prevenção & controle , Conhecimentos, Atitudes e Prática em Saúde , Homossexualidade Masculina , Humanos , Masculino , Aceitação pelo Paciente de Cuidados de Saúde , Parceiros Sexuais
8.
AIDS Behav ; 26(6): 2003-2014, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34997385

RESUMO

Despite having some of the world's highest rates of HIV, there is a lack of knowledge on correlates of transmission risk among gay, bisexual and other men who have sex with men in Southern Africa. There is even less known about the factors that shape HIV risk in male-male couples. Using data from Together Tomorrow, a study of partnered GBMSM in South Africa and Namibia, this study assessed the individual and dyadic correlates of three major HIV risk factors in this population: substance misuse, transactional sex, and depressive symptomatology. Data were collected during November 2016-March 2017 via a quantitative survey conducted with 140 partnered MSM (70 couples) in Windohoek, Keetmanshoop, Walvis Bay, and Swakopmund, Namibia and 300 partnered MSM (150 couples) in Pietermaritzburg and Durban, KwaZulu-Natal, South Africa for a total sample size of 440 partnered MSM (220 couples). Results of multilevel modeling analyses show several significant factors present in partnered GBMSM that differ from studies of single GBMSM, with intimate partner violence being a significant correlate across all three risk factors. Future interventions should consider dyadic approaches and integrate IPV prevention and mitigation efforts to reduce HIV in this population as part of a multisectoral approach. To reduce rates of HIV in partnered GBMSM in Namibia and South Africa multilevel, multisectoral work is needed in policy, social norms change, and relationship-focused dyadic interventions to reduce the social and structural stigma facing male couples.


Assuntos
Infecções por HIV , Minorias Sexuais e de Gênero , Transtornos Relacionados ao Uso de Substâncias , Infecções por HIV/epidemiologia , Infecções por HIV/prevenção & controle , Homossexualidade Masculina , Humanos , Masculino , Namíbia/epidemiologia , África do Sul/epidemiologia , Transtornos Relacionados ao Uso de Substâncias/epidemiologia
9.
AIDS Behav ; 26(7): 2338-2348, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35044555

RESUMO

This paper presents data from the Love and Sex in the Time of COVID survey, an online survey with US gay, bisexual and other men who have sex with men. The first round of the Love and Sex in the Time of COVID-19 survey was conducted online from April to May, 2020: the second round was collected November 2020 to January 2021. GBMSM were recruited through advertisements featured on social networking platforms. Analysis examines changes in self-reported measures of sexual behavior (number of sex partners, number of anal sex partners and number of anal sex partners not protected by pre-exposure prophylaxis (PrEP) or condoms) between those with complete data for round one and round two of the surveys (n = 280). While in round one, men reported a moderate willingness to have sex during COVID-19 (3.5 on a scale from 1 to 5), this had reduced significantly to 2.1 by round two. Men reported declines in the number of unprotected anal sex partners since pre-COVID. Perceptions of a longer time until the end of the COVID-19 pandemic were associated with increases in the number of sex partners and UAI partners. The results illustrate some significant declines in sexual behavior among GBMSM as the COVID-19 pandemic progressed. As vaccine programs continue to roll out across the U.S, as lockdowns ease and as we return to some normalcy, it will be important to continue to think critically about ways to re-engage men in HIV prevention.


Assuntos
COVID-19 , Comportamento Sexual , Minorias Sexuais e de Gênero , COVID-19/epidemiologia , COVID-19/prevenção & controle , Controle de Doenças Transmissíveis , Estudos Transversais , Infecções por HIV/prevenção & controle , Homossexualidade Masculina , Humanos , Masculino , Pandemias , Inquéritos e Questionários , Sexo sem Proteção/estatística & dados numéricos
10.
Arch Sex Behav ; 51(5): 2549-2562, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-34799830

RESUMO

Between one to two-thirds of HIV infections among gay, bisexual, and other men who have sex with men are from primary partners, and there has been increased research attention focused on strategies to increase PrEP adoption among male couples. While there is evidence that partner support is a strong correlate of pre-exposure prophylaxis (PrEP) adoption, there has been a lack of attention on PrEP communication dynamics among male couples. In this paper, we build upon this literature through analysis of dyadic data from a large cross-sectional survey of 543 concordant sero-negative and serodiscordant male couples to examine individual and relationship factors associated with reports of partner communication around PrEP, comfort in discussing PrEP, and perceived partner-level support for PrEP use. PrEP use was relatively low (16.2%), and although 87.5% of men reported their partners would support their PrEP use, only 26.3% had talked to their partner recently about PrEP. PrEP communication and perceived support for PrEP were significantly negatively associated with PrEP stigma and stigma based on sexuality (i.e., internalized homophobia and enacted external stigma based on sexuality), while men with sexual agreements were more comfortable talking about PrEP with their partner. There is a need to adapt current interventions, or develop new dyadic interventions, that provide opportunities for male couples to talk and learn about PrEP together, as a potential pathway to engage them toward PrEP use.


Assuntos
Infecções por HIV , Profilaxia Pré-Exposição , Minorias Sexuais e de Gênero , Comunicação , Estudos Transversais , Infecções por HIV/tratamento farmacológico , Infecções por HIV/prevenção & controle , Homossexualidade Masculina , Humanos , Masculino , Parceiros Sexuais , Apoio Social
11.
Br J Dermatol ; 184(2): 281-288, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-32282932

RESUMO

BACKGROUND: The presence of ulceration has been recognized as an adverse prognostic factor in primary cutaneous melanoma (PCM). OBJECTIVES: To investigate whether the extent of ulceration (EoU) predicts relapse-free survival (RFS) and overall survival (OS) in PCM. MATERIALS AND METHODS: We retrieved data for 477 patients with ulcerated PCM from databases of the Italian Melanoma Intergroup. Univariate and multivariable Cox proportional hazard models were used to assess the independent prognostic impact of EoU. RESULTS: A significant interaction emerged between Breslow thickness (BT) and EoU, considering both RFS (P < 0·0001) and OS (P = 0·0006). At multivariable analysis, a significant negative impact of EoU on RFS [hazard ratio (HR) (1-mm increase) 1·26, 95% confidence interval (CI) 1·08-1·48, P = 0·0047] and OS [HR (1-mm increase) 1·25, 95% CI 1·05-1·48, P = 0·0120] was found in patients with BT ≤ 2 mm, after adjusting for BT, age, tumour-infiltrating lymphocytes, sentinel lymph node status and mitotic rate. No impact of EoU was found in patients with 2·01-4 mm and > 4 mm BT. CONCLUSIONS: This study demonstrates that EoU has an independent prognostic impact in PCM and should be recorded as a required element in pathology reports.


Assuntos
Melanoma , Neoplasias Cutâneas , Humanos , Itália/epidemiologia , Melanoma/patologia , Estadiamento de Neoplasias , Prognóstico , Biópsia de Linfonodo Sentinela , Neoplasias Cutâneas/patologia
12.
AIDS Behav ; 25(1): 40-48, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32876905

RESUMO

This paper presents data from a recent cross-sectional survey of gay, bisexual and other men who have sex with men (GBMSM) in the US, to understand changes in sexual behavior and access to HIV prevention options (i.e. condoms and pre-exposure prophylaxis (PrEP)) during the COVID-19 lockdown period. The Love and Sex in the Time of COVID-19 survey was conducted online from April to May, 2020. GBMSM were recruited through advertisements featured on social networking platforms, recruiting a sample size of 518 GBMSM. Analysis considers changes three in self-reported measures of sexual behavior: number of sex partners, number of anal sex partners and number of anal sex partners not protected by pre-exposure prophylaxis (PrEP) or condoms. Approximately two-thirds of the sample reported that they believed it was possible to contract COVID-19 through sex, with anal sex reported as the least risky sex act. Men did not generally feel it was important to reduce their number of sex partners during COVID-19, but reported a moderate willingness to have sex during COVID-19. For the period between February and April-May 20,202, participants reported a mean increase of 2.3 sex partners during COVID-19, a mean increase of 2.1 anal sex partners (range - 40 to 70), but a very small increase in the number of unprotected anal sex partners. Increases in sexual behavior during COVID-19 were associated with increases in substance use during the same period. High levels of sexual activity continue to be reported during the COVID-19 lockdown period and these high levels of sexual activity are often paralleled by increases in substance use and binge drinking. There is a clear need to continue to provide comprehensive HIV prevention and care services during COVID-19, and telehealth and other eHealth platforms provide a safe, flexible mechanism for providing services.


Assuntos
Bissexualidade/psicologia , COVID-19/prevenção & controle , Infecções por HIV/tratamento farmacológico , Infecções por HIV/prevenção & controle , Homossexualidade Masculina/psicologia , Profilaxia Pré-Exposição , Comportamento Sexual/psicologia , Adolescente , Adulto , COVID-19/psicologia , Preservativos/estatística & dados numéricos , Estudos Transversais , Infecções por HIV/epidemiologia , Acessibilidade aos Serviços de Saúde , Humanos , Masculino , Pessoa de Meia-Idade , SARS-CoV-2 , Comportamento Sexual/estatística & dados numéricos , Parceiros Sexuais , Minorias Sexuais e de Gênero , Sexo sem Proteção/psicologia , Sexo sem Proteção/estatística & dados numéricos , Adulto Jovem
13.
BJOG ; 128(2): 329-335, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-32298518

RESUMO

OBJECTIVE: Fetal fractional limb volume has been proposed as a useful measure for quantifying fetal soft tissue development. The aim of this study was to investigate the growth of fractional arm volume (AVol) and fractional thigh volume (TVol) of fetuses with maternal gestational diabetes (GDM) compared with those of fetuses with normal glucose tolerance (NGT). We hypothesised fetal fractional limb volume would be larger in the GDM group than in the NGT group in late gestation. DESIGN: Exploratory observational study. SETTING: Saitama Municipal Hospital. SAMPLE: A total of 165 (125 NGT and 40 GDM) singleton Japanese pregnant women. METHODS: AVol and TVol were assessed between 20 and 37 weeks' gestation as cylindrical limb volumes based on 50% of the fetal humeral or femoral diaphysis length. Women were diagnosed as GDM based on the criteria of the Japan Society of Obstetrics and Gynecology. MAIN OUTCOME MEASURES: AVol and TVol were compared between women with NGT and those with GDM at each gestational age period (2-week intervals from 20 to 37 weeks' gestation). RESULTS: Overall, 287 ultrasound scans were performed (NGT group, 205 scans; GDM group, 82 scans). There was no significant difference of AVol between the groups before 32 weeks' gestation. AVol was significantly larger in the GDM group than in the NGT group after 32 weeks' gestation (P < 0.05). TVol was not statistically different between the groups across gestation. CONCLUSIONS: Detection of variations in fetal AVol may provide greater insight into understanding the origins of altered fetal body proportion in GDM. TWEETABLE ABSTRACT: AVol, but not TVol, is significantly larger in fetuses with GDM than in those with NGT after 32 weeks' gestation.


Assuntos
Braço/embriologia , Diabetes Gestacional/diagnóstico por imagem , Desenvolvimento Fetal/fisiologia , Feto/diagnóstico por imagem , Coxa da Perna/embriologia , Adulto , Braço/diagnóstico por imagem , Diáfises/diagnóstico por imagem , Diáfises/embriologia , Feminino , Fêmur/diagnóstico por imagem , Fêmur/embriologia , Idade Gestacional , Humanos , Úmero/diagnóstico por imagem , Úmero/embriologia , Japão , Tamanho do Órgão , Gravidez , Coxa da Perna/diagnóstico por imagem , Ultrassonografia Pré-Natal
14.
Folia Biol (Praha) ; 67(2): 62-69, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34624938

RESUMO

Hypoxia leads to post-treatment metastasis and recurrences of cancer via the epithelial-mesenchymal transition (EMT). Radiotherapy itself may also contribute to the acquisition of EMT phenotypes. Despite extensive studies on the EMT driven by either hypoxia or radiation stimuli, the molecular mechanisms characterizing these EMT events remain unclear. Thus, we aimed to evaluate the differences in the molecular pathways between hypoxia-induced EMT (Hypo-EMT) and radiation-induced EMT (R-EMT). Further, we investigated the therapeutic effects of HIF-1α inhibitor (LW6) on Hypo-EMT and R-EMT cells. A549 cells, lung adenocarcinoma cell line, acquired enhanced wound-healing activity under both hypoxia and irradiation. Localization of E-cadherin was altered from the cell membrane to the cytoplasm in both hypoxia and irradiated conditions. Of note, the expression levels of vimentin, one of the major EMT markers, was enhanced in irradiated cells, while it decreased under hypoxia condition. Importantly, LW6 significantly blocked EMT-related malignant phenotypes in both Hypo-EMT cells and R-EMT cells with concomitant re-location of E-cadherin onto the cell membrane. Moreover, LW6 deflected stress responsive signalling, JNK, activated sustainably under hypoxic condition, and the blockage of JNK impaired EMT phenotypes. Together, this work demonstrated the molecular events underlying Hypo-EMT and R-EMT, and highlighted HIF-1α as a therapeutic target not only in Hypo- EMT, but also in R-EMT.


Assuntos
Hipóxia Celular , Transição Epitelial-Mesenquimal , Fator 1 Induzível por Hipóxia/metabolismo , Neoplasias Pulmonares , Células A549 , Antígenos CD , Caderinas , Transição Epitelial-Mesenquimal/efeitos da radiação , Humanos , Subunidade alfa do Fator 1 Induzível por Hipóxia
15.
Nano Lett ; 20(10): 7476-7481, 2020 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-32897724

RESUMO

Magnetic Weyl semimetals attract considerable interest not only for their topological quantum phenomena but also as an emerging materials class for realizing quantum anomalous Hall effect in the two-dimensional limit. A shandite compound Co3Sn2S2 with layered kagome-lattices is one such material, where vigorous efforts have been devoted to synthesize the two-dimensional crystal. Here, we report a synthesis of Co3Sn2S2 thin flakes with a thickness of 250 nm by chemical vapor transport method. We find that this facile bottom-up approach allows the formation of large-sized Co3Sn2S2 thin flakes of high-quality, where we identify the largest electron mobility (∼2600 cm2 V-1 s-1) among magnetic topological semimetals, as well as the large anomalous Hall conductivity (∼1400 Ω-1 cm-1) and anomalous Hall angle (∼32%) arising from the Berry curvature. Our study provides a viable platform for studying high-quality thin flakes of magnetic Weyl semimetal and stimulate further research on unexplored topological phenomena in the two-dimensional limit.

16.
J Urol ; 204(6): 1195-1201, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-32516029

RESUMO

PURPOSE: The added value of nontargeted systematic prostate biopsies when performed alongside magnetic resonance imaging targeted biopsies in men referred with a suspicion of prostate cancer is unclear. We aimed to determine the clinical utility of transperineal nontargeted systematic prostate biopsies, when performed alongside targeted systematic prostate biopsies, using pre-biopsy multiparametric magnetic resonance imaging. MATERIALS AND METHODS: Consecutive patients referred with a suspicion of prostate cancer (April 2017 to October 2019) underwent pre-biopsy multiparametric magnetic resonance imaging. A transperineal biopsy was advised if multiparametric magnetic resonance imaging PI-RADS® (v.2.0) score was 4 or 5, and score 3 required a prostate specific antigen density 0.12 ng/ml or greater. Primary threshold for clinically significant prostate cancer was defined as any Gleason 3+4 or greater. Multivariable logistic regression analysis identified pre-biopsy predictors of clinically significant prostate cancer in nontargeted systematic prostate biopsies, regardless of targeted pathology (p <0.05, R, version 3.5.1). RESULTS: A total of 1,719 men underwent a pre-biopsy multiparametric magnetic resonance imaging, with 679 (39.5%) proceeding to combined targeted systematic prostate biopsies and nontargeted systematic prostate biopsies. In these men clinically significant prostate cancer was detected in 333 (49%) and 139 (20.5%) with targeted systematic prostate biopsies and nontargeted systematic prostate biopsies, respectively. In those men with clinically significant prostate cancer in targeted systematic prostate biopsies, clinically significant prostate cancer was also present in nontargeted systematic prostate biopsies in 117 (17.2%); Gleason 3+3 was present in 50 (7.4%). In 287 men without any cancer in the targeted systematic prostate biopsies, 13 (1.9%) had clinically significant prostate cancer in nontargeted systematic prostate biopsies. In addition 18/679 (2.7%) had Gleason 3+3 disease and no Gleason greater than 4+3 was detected. Predictors associated with clinically significant prostate cancer in nontargeted systematic prostate biopsies were prostate specific antigen 5 ng/ml or greater (OR 2.05, 95% CI 1.13-3.73, p=0.02), PI-RADS score 5 (OR 2.26, 95% CI 1.51-3.38, p <0.001) and prostate volume less than 50 cc (OR 2.47, 95% CI 1.57-3.87, p <0.001). CONCLUSIONS: Detection of clinically significant prostate cancer in exclusively nontargeted transperineal systematic biopsies in a pre-biopsy multiparametric magnetic resonance imaging pathway was low (1.9%).


Assuntos
Imageamento por Ressonância Magnética Multiparamétrica , Próstata/patologia , Neoplasias da Próstata/diagnóstico , Idoso , Biópsia com Agulha de Grande Calibre/métodos , Biópsia com Agulha de Grande Calibre/estatística & dados numéricos , Humanos , Biópsia Guiada por Imagem/métodos , Biópsia Guiada por Imagem/estatística & dados numéricos , Calicreínas/sangue , Masculino , Pessoa de Meia-Idade , Períneo/cirurgia , Estudos Prospectivos , Próstata/diagnóstico por imagem , Antígeno Prostático Específico/sangue , Neoplasias da Próstata/sangue , Neoplasias da Próstata/patologia
17.
Osteoarthritis Cartilage ; 28(1): 82-91, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31526878

RESUMO

OBJECTIVE: To evaluate the degree of knee fat pad abnormalities after acute anterior cruciate ligament (ACL) tear via magnetic resonance fat pad scoring and to assess cross-sectionally its association with synovial fluid biomarkers and with early cartilage damage as quantified via T1ρ and T2 relaxation time measurements. DESIGN: 26 patients with acute ACL tears underwent 3T MR scanning of the injured knee prior to ACL reconstruction. The presence and degree of abnormalities of the infrapatellar (IPFP) and the suprapatellar (SPFP) fat pads were scored on MR images along with grading of effusion-synovitis and synovial proliferations. Knee cartilage composition was assessed by 3T MR T1ρ and T2 mapping in six knee compartments. We quantified concentrations of 20 biomarkers in synovial fluid aspirated at the time of ACL reconstruction. Spearman rank partial correlations with adjustments for age and gender were employed to evaluate correlations of MR, particularly cartilage composition and fat pad abnormalities, and biomarker data. RESULTS: The degree of IPFP abnormality correlated positively with the synovial levels of the inflammatory cytokine markers IFN-γ (ρpartial = 0.64, 95% CI (0.26-0.85)), IL-10 (ρpartial = 0.47, 95% CI (0.04-0.75)), IL-6 (ρpartial = 0.56, 95% CI (0.16-0.81)), IL-8 (ρpartial = 0.49, 95% CI (0.06-0.76)), TNF-α (ρpartial = 0.55, 95% CI (0.14-0.80)) and of the chondrodestructive markers MMP-1 and -3 (MMP-1: ρpartial = 0.57, 95% CI (0.17-0.81); MMP-3: ρpartial = 0.60, 95% CI (0.21-0.83)). IPFP abnormalities were significantly associated with higher T1ρ and T2 values in the trochlear cartilage (T1ρ: ρpartial = 0.55, 95% CI (0.15-0.80); T2: ρpartial = 0.58, 95% CI (0.18-0.81)) and with higher T2 values in the medial femoral, medial tibial as well as in patellar cartilage (0.45 ≤ ρpartial ≤ 0.59). Correlations between SPFP abnormalities and synovial markers were not significant except for IL-6 (ρpartial = 0.57, 95% CI (0.17-0.81)). CONCLUSIONS: This exploratory study suggests that acute ACL rupture can be associated with damage to knee tissues such as the inferior fat pad of the knee. Such fat pad injury could be partially responsible for the apparent post-injury pro-inflammatory response noted in ACL-injured individuals. However, future longitudinal studies are needed to link ACL-rupture associated fat pad injury with important patient outcomes such as the development of posttraumatic osteoarthritis.


Assuntos
Tecido Adiposo/patologia , Lesões do Ligamento Cruzado Anterior/metabolismo , Citocinas/metabolismo , Joelho/patologia , Líquido Sinovial/metabolismo , Tecido Adiposo/diagnóstico por imagem , Adulto , Lesões do Ligamento Cruzado Anterior/patologia , Reconstrução do Ligamento Cruzado Anterior , Citocinas/análise , Feminino , Humanos , Joelho/diagnóstico por imagem , Imageamento por Ressonância Magnética , Masculino , Líquido Sinovial/química , Sinovite/diagnóstico por imagem , Sinovite/metabolismo , Sinovite/patologia
18.
Osteoarthritis Cartilage ; 28(12): 1539-1550, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-32739341

RESUMO

OBJECTIVE: To develop 3D T1ρ and T2 imaging based on the same sequence structure on MR systems from multiple vendors, and to evaluate intra-site repeatability and inter-site inter-vendor reproducibility of T1ρ and T2 measurements of knee cartilage. METHODS: 3D magnetization-prepared angle-modulated partitioned k-space spoiled gradient echo snapshots (3D MAPSS) were implemented on MR systems from Siemens, GE and Philips. Phantom and human subject data were collected at four sites using 3T MR systems from the three vendors with harmonized protocols. Phantom data were collected by means of different positioning of the coil. Volunteers were scanned and rescanned after repositioning. Two traveling volunteers were scanned at all sites. Data were transferred to one site for centralized processing. RESULTS: Intra-site average coefficient of variations (CVs) ranged from 1.09% to 3.05% for T1ρ and 1.78-3.30% for T2 in phantoms, and 1.60-3.93% for T1ρ and 1.44-4.08% for T2 in volunteers. Inter-site average CVs were 5.23% and 6.45% for MAPSS T1ρ and T2, respectively in phantoms, and 8.14% and 10.06% for MAPSS T1ρ and T2, respectively, In volunteers. CONCLUSION: This study showed promising results of multi-site, multi-vendor reproducibility of T1ρ and T2 values in knee cartilage. These quantitative measures may be applied in large-scale multi-site, multi-vendor trials with controlled sequence structure and scan parameters and centralized data processing.


Assuntos
Cartilagem Articular/diagnóstico por imagem , Articulação do Joelho/diagnóstico por imagem , Imageamento por Ressonância Magnética/métodos , Humanos , Processamento de Imagem Assistida por Computador , Imagens de Fantasmas , Reprodutibilidade dos Testes
19.
Br J Surg ; 107(12): 1673-1685, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32432347

RESUMO

BACKGROUND: Laparoscopic sleeve gastrectomy (LSG) is a well established treatment for severe obesity and type 2 diabetes. Although the gut microbiota is linked to the efficacy of LSG, the underlying mechanisms remain elusive. The effect of LSG for morbid obesity on the gut microbiota and bile acids was assessed here. METHODS: Severely obese subjects who were candidates for LSG were included and followed until 6 months after surgery. The composition and abundance of the microbiota and bile acids in faeces were assessed by 16S ribosomal RNA sequencing, quantitative PCR and liquid chromatography-mass spectrometry. RESULTS: In total, 28 patients with a mean(s.d.) BMI of 44·2(6·6) kg/m2 were enrolled. These patients had achieved excess weight loss of 53·2(19·0) per cent and showed improvement in metabolic diseases by 6 months after LSG, accompanied by an alteration in the faecal microbial community. The increase in α-diversity and abundance of specific taxa, such as Rikenellaceae and Christensenellaceae, was strongly associated with reduced faecal bile acid levels. These changes had a significant positive association with excess weight loss and metabolic alterations. However, the total number of faecal bacteria was lower in patients before (mean(s.d.) 10·26(0·36) log10 cells per g faeces) and after (10·39(0·29) log10 cells per g faeces) operation than in healthy subjects (10·83(0·27) log10 cells per g faeces). CONCLUSION: LSG is associated with a reduction in faecal bile acids and greater abundance of specific bacterial taxa and α-diversity that may contribute to the metabolic changes.


ANTECEDENTES: La gastrectomía vertical laparoscópica (laparoscopic sleeve gastrectomy, LSG) es un tratamiento bien establecido para la obesidad grave y la diabetes tipo 2. Aunque la microbiota intestinal se ha vinculado con la eficacia de LSG, los mecanismos subyacentes siguen siendo poco conocidos. En este estudio se evaluó el efecto de LSG en la obesidad mórbida sobre la microbiota del intestino y de los ácidos biliares (bile acids, BA). MÉTODOS: Tras la aprobación del Comité ético y la obtención del consentimiento informado, los sujetos con obesidad grave que eran candidatos para LSG fueron incluidos en el estudio y seguidos durante 6 meses después de la operación. Se evaluaron la composición y abundancia de la microbiota y BA en las heces mediante secuenciación del gen 16S rRNA, PCR cuantitativa y cromatografía líquida-espectrometría de masas. RESULTADOS: En total, 28 pacientes con una mediana (rango) del IMC de 43,9 kg/m2 (35,0-61,9) fueron reclutados y a los 6 meses tras una LSG, consiguieron una pérdida del exceso de peso de 47,3% (20,7-95,1) y mejoría de las enfermedades metabólicas acompañada de una alteración en la comunidad microbiana fecal. El aumento en la diversidad α y abundancia de especies taxonómicas específicas como Rikenellaceae y Christensenellaceae, se asociaba fuertemente con niveles fecales reducidos de BA. Estos cambios se asociaban de manera positiva y significativa con la pérdida del exceso de peso y las alteraciones metabólicas. Sin embargo, el número total de bacterias fecales en los pacientes fue inferior al de los sujetos sanos (10,84 log10 células/g heces (9,46-11,35)) antes de la operación (10,26 log10 células/g heces (9,44-10,91)) y después de la misma (10,42 log10 células/g heces (9,57-10,96)). CONCLUSIÓN: LSG se asoció con menos BA fecal y mayor abundancia de especies bacterianas específicas y diversidad α lo que puede contribuir a los cambios metabólicos.


Assuntos
Ácidos e Sais Biliares/análise , Fezes/química , Gastrectomia/métodos , Laparoscopia/estatística & dados numéricos , Obesidade Mórbida/cirurgia , Adulto , Carga Bacteriana , Biodiversidade , Diabetes Mellitus Tipo 2/microbiologia , Fezes/microbiologia , Feminino , Microbioma Gastrointestinal/genética , Humanos , Concentração de Íons de Hidrogênio , Masculino , Obesidade Mórbida/microbiologia , RNA Ribossômico 16S/genética
20.
Phys Rev Lett ; 124(10): 102501, 2020 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-32216444

RESUMO

Interaction cross sections for ^{42-51}Ca on a carbon target at 280 MeV/nucleon have been measured for the first time. The neutron number dependence of derived root-mean-square matter radii shows a significant increase beyond the neutron magic number N=28. Furthermore, this enhancement of matter radii is much larger than that of the previously measured charge radii, indicating a novel growth in neutron skin thickness. A simple examination based on the Fermi-type distribution, and mean field calculations point out that this anomalous enhancement of the nuclear size beyond N=28 results from an enlargement of the core by a sudden increase in the surface diffuseness of the neutron density distribution, which implies the swelling of the bare ^{48}Ca core in Ca isotopes beyond N=28.

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