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1.
Nature ; 595(7866): 223-226, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-34234332

RESUMO

Neutron-star mergers were recently confirmed as sites of rapid-neutron-capture (r-process) nucleosynthesis1-3. However, in Galactic chemical evolution models, neutron-star mergers alone cannot reproduce the observed element abundance patterns of extremely metal-poor stars, which indicates the existence of other sites of r-process nucleosynthesis4-6. These sites may be investigated by studying the element abundance patterns of chemically primitive stars in the halo of the Milky Way, because these objects retain the nucleosynthetic signatures of the earliest generation of stars7-13. Here we report the element abundance pattern of the extremely metal-poor star SMSS J200322.54-114203.3. We observe a large enhancement in r-process elements, with very low overall metallicity. The element abundance pattern is well matched by the yields of a single 25-solar-mass magnetorotational hypernova. Such a hypernova could produce not only the r-process elements, but also light elements during stellar evolution, and iron-peak elements during explosive nuclear burning. Hypernovae are often associated with long-duration γ-ray bursts in the nearby Universe8. This connection indicates that similar explosions of fast-spinning strongly magnetized stars occurred during the earliest epochs of star formation in our Galaxy.

2.
Epidemiol Infect ; 143(13): 2841-8, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25600903

RESUMO

A contact investigation following a case of infectious tuberculosis (TB) reported in a call centre in Milan (Italy) led to the identification of three additional cases that had occurred in employees of the same workplace during the previous 5 years, one of whom was the probable source case. Thirty-three latent infections were also identified. At the time of diagnosis, the source case, because of fear of stigma related to TB, claimed to be unemployed and a contact investigation was not performed in the workplace. Cases were linked through genotyping of Mycobacterium tuberculosis. TB stigma has been described frequently, mainly in high-incidence settings, and is known to influence health-seeking behaviours and treatment adherence. The findings in this report highlight that TB-associated stigma may also lead to incomplete contact investigations. Little is known about the causes and impact of TB-related stigma in low-incidence countries and this warrants further exploration. Research is also needed to evaluate the effectiveness of specific interviewing techniques and training interventions for staff in reducing feelings of stigma in TB patients. Finally, the outbreak emphasizes the importance of integrating routine contact investigations with genotyping.


Assuntos
Busca de Comunicante , Estigma Social , Tuberculose Pulmonar/epidemiologia , Tuberculose Pulmonar/psicologia , Adulto , Surtos de Doenças , Feminino , Humanos , Incidência , Itália/epidemiologia , Masculino , Tuberculose Pulmonar/transmissão
3.
J Hum Hypertens ; 21(5): 366-73, 2007 May.
Artigo em Inglês | MEDLINE | ID: mdl-17301825

RESUMO

The present study evaluated the prevalence of hypertension (HT) and its possible relationships with various risk factors in a representative sample (n=2884) of the adult population (>18 years old) of Galicia, a region of Spain. Subjects were selected by a two-step cluster sampling procedure from the Galician public health service database, which covers more than 95% of the population (2.7 million inhabitants). The overall prevalence of HT, defined as BP >140/90 mm Hg and/or current treatment with antihypertensive medication, was 25.5%, higher in men (31.1%) than in women (20.7%). Of the hypertensive subjects 50.6% were aware of the HT; of these, 72.0% were receiving treatment and 36.4% were treated and controlled. The prevalence of HT increased with age and was higher in subjects from urban areas than rural areas and higher in subjects with low educational level. Surprisingly, people with low educational level more frequently showed awareness of HT than people with high education level. Increased body mass index was related to increased prevalence of HT and close associations were observed between HT and cardiovascular diseases. Our data also show a linear upward trend in blood pressure from normal glucose metabolism to diabetes mellitus. Surprisingly, the prevalence of HT among people with known diabetes was higher than among people with undetected diabetes, which may indicate poor control of HT in diabetic subjects.


Assuntos
Anti-Hipertensivos/uso terapêutico , Conscientização , Hipertensão/epidemiologia , Hipertensão/prevenção & controle , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Pressão Sanguínea/efeitos dos fármacos , Índice de Massa Corporal , Doenças Cardiovasculares/complicações , Doenças Cardiovasculares/epidemiologia , Análise por Conglomerados , Complicações do Diabetes/epidemiologia , Escolaridade , Feminino , Humanos , Hipertensão/complicações , Hipertensão/tratamento farmacológico , Hipertensão/fisiopatologia , Masculino , Pessoa de Meia-Idade , Obesidade/complicações , Obesidade/epidemiologia , Prevalência , Fatores de Risco , População Rural/estatística & dados numéricos , Espanha/epidemiologia , Inquéritos e Questionários , Resultado do Tratamento , População Urbana/estatística & dados numéricos
4.
Sex Transm Dis ; 9(3): 132-4, 1982.
Artigo em Inglês | MEDLINE | ID: mdl-6216611

RESUMO

In Norfolk, Virginia, two epidemics of disease due to proved penicillinase-producing Neisseria gonorrhoeae were investigated intensively, both epidemiologically and medically. The first epidemic appeared in October 1976 and was controlled in one month; it was followed by a hiatus of four years before the emergence of the second epidemic in October 1980. The latter apparently was brought under control by December 1980, since no more patients with penicillinase-producing N. gonorrhoeae have been discovered to date (March 1982). Certain interesting medical aspects emerged from the investigation. Resistant organisms were cultured from asymptomatic as well as symptomatic patients and from all potentially infected sites. At times, resistant organisms were cultured from only one of several sites in a given patient or both resistant and sensitive organisms were cultured from a single site. It was concluded that this type of gonorrhea can be contained by intensive epidemiologic investigation combined with adequate diagnosis and treatment.


Assuntos
Controle de Doenças Transmissíveis , Surtos de Doenças/epidemiologia , Gonorreia/epidemiologia , Neisseria gonorrhoeae/metabolismo , Penicilinase/biossíntese , beta-Lactamases/biossíntese , Resistência Microbiana a Medicamentos , Estudos de Avaliação como Assunto , Feminino , Humanos , Neisseria gonorrhoeae/isolamento & purificação , Salpingite/complicações , Espectinomicina/uso terapêutico , Virginia
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