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2.
Nat Commun ; 14(1): 1335, 2023 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-36906683

RESUMO

Oceanic eddy-induced meridional heat transport (EHT) is an important process in the Southern Ocean heat budget, the variability of which significantly modulates global meridional overturning circulation (MOC) and Antarctic sea-ice extent. Although it is recognized that mesoscale eddies with scales of ~40-300 km greatly contribute to the EHT, the role of submesoscale eddies with scales of ~1-40 km remains unclear. Here, using two state-of-the-art high-resolution simulations (resolutions of 1/48° and 1/24°), we find that submesoscale eddies significantly enhance the total poleward EHT in the Southern Ocean with an enhancement percentage reaching 19-48% in the Antarctic Circumpolar Current band. By comparing the eddy energy budgets between the two simulations, we detect that the primary role of submesoscale eddies is to strengthen mesoscale eddies (and thus their heat transport capability) through inverse energy cascade rather than directly through submesoscale heat fluxes. Due to the submesoscale-mediated enhancement of mesoscale eddies in the 1/48° simulation, the clockwise upper cell and anti-clockwise lower cell of the residual-mean MOC in the Southern Ocean are weakened and strengthened, respectively. This finding identifies a potential route to improve the mesoscale parameterization in climate models for more accurate simulations of the MOC and sea ice variability in the Southern Ocean.

3.
Medicine (Baltimore) ; 97(9): e0053, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29489662

RESUMO

Telbivudine is an orally nucleoside analog with potent and specific antihepatitis B virus (HBV) activity, and it has been reported to block mother-to-infant transmission. However, few studies have focused on the safety of prenatal exposure for offspring development.This is a prospective noninterventional study. Participants were enrolled during delivery through the Women's Hospital of Zhejiang University School of Medicine between January 2012 and September 2013. Neonate's umbilical cord arterial blood (UCAB) was collected after delivery. Hepatitis B virus DNA copy, HBV serology, alanine aminotransferase (ALT), creatine kinase (CK), creatinine (CRE), and blood urea nitrogen (BUN) were measured. The development of the offspring was evaluated by the Chinese Revision of Bayley Scales of Child Development (BSCD-CR) at 12 to 24 months old.Around 30 and 31 chronic hepatitis B mothers were recruited in untreated group (non-LdT group) and telbivudine-treatment group (LdT group), respectively, and 2 children (one in non-LdT group and 1 in LdT group) were lost in follow-up. Sixty-one normal women and their children were recruited as a normal control (control group). Compared with non-LdT group, telbivudine treatment effectively blocks HBV transmission from mother to infant. However, CK in UCAB was significantly increased in the LdT group. Moreover, children with prenatal telbivudine exposure showed lower level of serum creatinine than non-LdT group, reduction of psychomotor developmental index and increased risk of motor development delay.Prenatal telbivudine exposure is correlated with motor development delay in offspring.


Assuntos
Antivirais/efeitos adversos , Deficiências do Desenvolvimento/induzido quimicamente , Hepatite B Crônica/tratamento farmacológico , Transmissão Vertical de Doenças Infecciosas/prevenção & controle , Efeitos Tardios da Exposição Pré-Natal/induzido quimicamente , Timidina/análogos & derivados , Adulto , DNA Viral/sangue , Feminino , Vírus da Hepatite B , Humanos , Lactente , Recém-Nascido , Masculino , Gravidez , Estudos Prospectivos , Telbivudina , Timidina/efeitos adversos , Adulto Jovem
4.
J Zhejiang Univ Sci B ; 10(1): 35-45, 2009 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-19198021

RESUMO

OBJECTIVE: We dynamically measured serum inhibin B and estradiol in the early stage of hormonal stimulation to predict the ovarian response in in vitro fertilization (IVF) treatment. METHODS: A total of 57 patients (<40 years of age) who underwent the first cycle of long protocol IVF or introcytoplasmic sperm injection (ICSI) treatment were included. Serum inhibin B, estradiol, follicle stimulating hormone (FSH) and luteinizing hormone (LH) levels were measured four times: (1) on Day 3 of the menstrual cycle (basal); (2) on the day before the first administration of gonadotrophin (Gn) (Day 0); (3) on Day 1 of Gn therapy; and (4) on Day 5 of Gn therapy. Comparisons of these measurements with ovarian responses and pregnancy outcomes were made and analyzed statistically. RESULTS: (1) On Day 1 and Day 5 of recombinant FSH (rFSH) stimulation, ovarian response, i.e., numbers of follicles, oocytes, fertilized oocytes, and embryos, had a positive correlation (r(s)=0.46~0.61, P=0.000) with raised inhibin B and estradiol concentrations, but a negative correlation (r(s)=-0.67~-0.38, P=0.000 or P<0.01) with total rFSH dose and total days of rFSH stimulation. (2) No significant variation (P>0.05) between the pregnant and non-pregnant groups on the basis of mean age or on all hormone concentrations at four times of the IVF cycle was observed. However, all the seven patients aged >35 years did not reach pregnancy. CONCLUSIONS: (1) Serum inhibin B and estradiol concentrations obtained shortly after Gn therapy may offer an accurate and early prediction of ovarian response; (2) Low levels of serum inhibin B and estradiol obtained shortly after Gn stimulation indicate the need for a longer period of Gn treatment and a higher daily dosage; (3) No obvious pregnancy difference among patients of age <35 years was found; however, IVF pregnancy outcome is significantly lower in women of age >35 years.


Assuntos
Estradiol/sangue , Fertilização in vitro , Hormônio Foliculoestimulante/uso terapêutico , Infertilidade Feminina/sangue , Infertilidade Feminina/terapia , Inibinas/sangue , Ovário/efeitos dos fármacos , Indução da Ovulação/métodos , Adulto , Contagem de Células , Feminino , Hormônio Foliculoestimulante/administração & dosagem , Humanos , Infertilidade Feminina/patologia , Ciclo Menstrual , Oócitos , Folículo Ovariano/efeitos dos fármacos , Folículo Ovariano/fisiologia , Ovário/fisiologia , Prognóstico , Resultado do Tratamento
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