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1.
Inorg Chem ; 62(19): 7160-7164, 2023 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-37125783

RESUMO

Hg-based chalcogenides possess diverse structures, large nonlinear-optical (NLO) responses, and suitable birefringences, making them potentially suitable for numerous crucial criteria of practical application as infrared (IR) NLO crystals. Here, a new pentanary Hg-based sulfide K2Ba7HgIn4S16 has been discovered by a high-temperature solid-state method. It crystallizes in the orthorhombic P21212 space group, and its one-dimensional structure is constructed by {[In2S7]8-}∞ chains and isolated [HgS4]6- planar quadrilateral units located bewteeen the chains, representing a novel type of chalcogenide. K2Ba7HgIn4S16 exhibits a moderate NLO effect of 0.5 × AGS at 2.1 µm and a high laser-induced damage threshold of ∼5.8 × AGS, as well as a band gap of 2.98 eV, demonstrating that K2Ba7HgIn4S16 is a potential IR NLO material. This work enriches the structural chemistry of chalcogenides and the family of Hg-based IR NLO chalcogenides.

2.
FASEB J ; 34(9): 13049-13062, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32779304

RESUMO

Life does not sustain without water. For water, there is a natural abundance of stable isotope hydrogen and oxygen. Water molecules get across cell membranes through a plasma membrane protein, named aquaporin. Moreover, the kidney is the main organ to maintain water homeostasis. Here, we study the stable isotopic ratios of hydrogen and oxygen in human blood plasma and erythrocyte corresponding to kidney functions. We extract waters from human plasma and erythrocyte, collected from 110 participants, including 51 clinically stable outpatients with end-stage renal disease (ESRD) and 59 subjects with normal renal function (NRF). We observed that (i) both extracellular (blood plasma) and intracellular (erythrocyte) biology waters are isotopic differences between the ESRD and NRF participants, (ii) the natural abundance of isotopic waters of ESRD is hypo-isotopic, and (iii) the isotopic enrichment of water between erythrocyte and blood plasma are distinct. In addition, we introduce an empirical formula using entropy transformation to describe isotopic water enrichment for biology. Accordingly, the natural abundance of stable isotope water of blood plasma and erythrocyte may be possibly put in practice a new sign for assessments of kidney dysfunctions.


Assuntos
Eritrócitos/metabolismo , Hidrogênio/sangue , Falência Renal Crônica/metabolismo , Oxigênio/sangue , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Taiwan , Adulto Jovem
3.
Mol Biol Evol ; 36(5): 999-1007, 2019 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-30861070

RESUMO

The ribosome is responsible for protein synthesis in all living organisms. It is best known to exist around 3.5-3.7 Ga whereat life on Earth inhabited anoxic environment with abundant soluble irons. The RNAs and proteins are the two biopolymers that constitute the ribosome. However, both proteins and RNAs require metal cations to fold and to function. There are four Mg-microcluster (Mg2+-µc) structures conserved in core of large subunit, and the 23S ribosomal RNA (rRNA) was shown to catalyze electron transfer in an anoxic environment in the presence of Fe2+. The Mg2+-µc features two idiosyncratic Mg2+ ions that are chelated and bridged by a common phosphate group and along with that, the adjacent residues of RNA backbone together forming ten-membered chelation ring(s). Here, we utilized four rRNA fragments of the large subunit 23S rRNA of Haloarcula marismortui, that includes the residues that form the four Mg2+-µc's. These four rRNA fragments are shown competent to assemble with Mg2+. Our results show that when these rRNA fragments fold or assembly in the presence of Fe2+ under anoxic conditions, each Fe2+-microcluster can catalyze electron transfer. We propose that Fe2+-microclusters of the ribosome, which use Fe2+ as a cofactor to regulate electron transfer, are pivotal and primordial and may be an origin in evolution of the ribosome.


Assuntos
Transporte de Elétrons , Ferro/metabolismo , Magnésio/metabolismo , RNA Ribossômico 23S/metabolismo , Ribossomos , Haloarcula marismortui
5.
Bioresour Technol ; 2012 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-23265818

RESUMO

This article has been withdrawn at the request of the author(s) and/or editor. The Publisher apologizes for any inconvenience this may cause. The full Elsevier Policy on Article Withdrawal can be found at http://www.elsevier.com/locate/withdrawalpolicy.

6.
Int Urogynecol J Pelvic Floor Dysfunct ; 20(7): 819-25, 2009 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-19495544

RESUMO

INTRODUCTION AND HYPOTHESIS: This study was conducted to determine whether urgency-free interval (UFI) was effective to evaluate the outcome of overactive bladder (OAB) and the correlation of changes between this parameter and urgency episodes. METHODS: A randomized placebo-controlled trial was conducted involving 73 women with OAB. The interventions for a 12-week period included a vaginal electric stimulation and oxybutynin (2.5 mg) or placebo three times per day. Identical preintervention and postintervention assessments included the measurement of UFI and warning time (WT). The King's Health Questionnaire, Spearman's correlation coefficient (SCC), Kruskal-Wallis, Mann-Whitney U, and Wilcoxon-signed rank tests were used for analysis. RESULTS: A positive and significant correlation between the improvements of WT and UFI was noted in the oxybutynin group (p = 0.009). In all groups, none of the SCC revealed significant correlation between the improvement of UFI and urgency episodes (all p >or= 0.145). CONCLUSIONS: The efficacy of UFI in evaluating treatment outcome of OAB was comparable with that of WT in selected modality.


Assuntos
Terapia por Estimulação Elétrica/métodos , Determinação de Ponto Final , Ácidos Mandélicos/uso terapêutico , Parassimpatolíticos/uso terapêutico , Bexiga Urinária Hiperativa/terapia , Incontinência Urinária de Urgência/fisiopatologia , Adulto , Feminino , Inquéritos Epidemiológicos , Humanos , Incidência , Pessoa de Meia-Idade , Prognóstico , Fatores de Tempo , Resultado do Tratamento , Incontinência Urinária de Urgência/diagnóstico , Incontinência Urinária de Urgência/epidemiologia
7.
Br J Haematol ; 117(1): 159-63, 2002 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-11918548

RESUMO

The biological effects of age, sex and vitamin status on plasma total homocysteine (tHcy), and association of hyperhomocysteinaemia with venous thromboembolism in Taiwanese Chinese individuals, were investigated. Eighty patients (16-85 years) with venous thrombophilia and 123 healthy subjects (15-85 years) without history of vascular thrombosis were studied for plasma levels of tHcy, folate and vitamin B12. A multivariate analysis in healthy subjects revealed that plasma tHcy levels tended to increase with age (P < 0.001) and with decreasing plasma levels of folate (P=0.001) or vitamin B12 (P < 0.029); men tended to have higher plasma tHcy levels than women (P=0.006). Thrombotic risk assessment in a case-control study demonstrated that neither plasma level of tHcy [odds ratio (OR), 1.07; 95% confidence interval (CI), 0.96-1.18; P=0.210] nor hyperhomocysteinaemia (OR, 1.65; 95% CI, 0.50-5.49; P=0.415) was significantly associated with venous thrombophilia. The relationship between hyperhomocysteinaemia and recurrence of episode remained insignificant (P=0.560). We conclude that age, sex and vitamin status affect plasma tHcy but hyperhomocysteinaemia is possibly not an important risk factor for venous thrombophilia in Taiwanese Chinese.


Assuntos
Hiper-Homocisteinemia/complicações , Trombofilia/etiologia , Adolescente , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Estudos de Casos e Controles , China/etnologia , Feminino , Ácido Fólico/sangue , Humanos , Masculino , Pessoa de Meia-Idade , Estado Nutricional , Razão de Chances , Fatores de Risco , Fatores Sexuais , Taiwan , Vitamina B 12/sangue
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