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1.
Vox Sang ; 112(7): 671-677, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28836328

RESUMO

BACKGROUND: The band 3 macrocomplex (also known as the ankyrin-associated complex) on the red cell membrane comprises two interacting subcomplexes: a band 3/glycophorin A subcomplex, and a Rh/RhAG subcomplex. Glycophorin B (GPB) is a component of the Rh/RhAG subcomplex that is also structurally associated with glycophorin A (GPA). Expression of glycophorin B-A-B hybrid GP.Mur enhances band 3 expression and is associated with lower levels of Rh-associated glycoprotein (RhAG) and Rh polypeptides. The goal of this study was to determine whether GP.Mur influenced erythroid Rh/RhAG expression at the transcript level. MATERIALS AND METHODS: GP.Mur was serologically determined in healthy participants from Taitung County, Taiwan. RNA was extracted from the reticulocyte-enriched fraction of peripheral blood, followed by reverse transcription and quantitative PCR for RhAG, RhD and RhCcEe. RESULTS: Quantification by real-time PCR revealed significantly fewer RhAG and RhCcEe transcripts in the reticulocytes from subjects with homozygous GYP*Mur. Independent from GYP.Mur, both RhAG and RhD transcript levels were threefold or higher than that of RhCcEe. Also, in GYP.Mur and the control samples alike, direct quantitative associations were observed between the transcript levels of RhAG and RhD, but not between that of RhAG and RhCcEe. CONCLUSION: Erythroid RhD and RhCcEe were differentially expressed at the transcript levels, which could be related to their different degrees of interaction or sensitivity to RhAG. Further, the reduction or absence of glycophorin B in GYP.Mur erythroid cells affected transcript expressions of RhAG and RhCcEe. Thus, GPB and GP.Mur differentially influenced Rh/RhAG expressions prior to protein translation.


Assuntos
Células Eritroides/metabolismo , Glicoforinas/genética , Sistema do Grupo Sanguíneo Rh-Hr/genética , Glicoforinas/sangue , Glicoforinas/metabolismo , Humanos , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Sistema do Grupo Sanguíneo Rh-Hr/sangue , Sistema do Grupo Sanguíneo Rh-Hr/metabolismo , Taiwan
2.
Theor Popul Biol ; 112: 80-96, 2016 12.
Artigo em Inglês | MEDLINE | ID: mdl-27591978

RESUMO

We study a variant of Hanski's incidence function model that allows habitat patch characteristics to vary over time following a Markov process. The widely studied case where patches are classified as either suitable or unsuitable is included as a special case. For large metapopulations, we determine a recursion for the probability that a given habitat patch is occupied. This recursion enables us to clarify the role of landscape dynamics in the survival of a metapopulation. In particular, we show that landscape dynamics affects the persistence and equilibrium level of the metapopulation primarily through its effect on the distribution of a local population's life span.


Assuntos
Ecossistema , Modelos Biológicos , Dinâmica Populacional , Cadeias de Markov
4.
Neurosignals ; 21(1-2): 42-54, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-22377595

RESUMO

In the present study, N-methyl-D-aspartate receptor 2B (NR2B)-specific siRNA was applied in parkinsonian models. Our previous results showed that reduction in expression of N-methyl-D-aspartate receptor 1 (NR1), the key subunit of N-methyl-D-aspartate receptors, by antisense oligos ameliorated the motor symptoms in the 6-hydroxydopamine (6-OHDA)-lesioned rat, an animal model of Parkinson's disease (PD).


Assuntos
Neurônios Dopaminérgicos/metabolismo , Sistema de Sinalização das MAP Quinases/fisiologia , Fármacos Neuroprotetores/metabolismo , RNA Interferente Pequeno/biossíntese , Receptores de N-Metil-D-Aspartato/biossíntese , Animais , Modelos Animais de Doenças , Neurônios Dopaminérgicos/patologia , Ativação Enzimática/fisiologia , Masculino , Transtornos Parkinsonianos/metabolismo , Transtornos Parkinsonianos/patologia , Transtornos Parkinsonianos/prevenção & controle , RNA Interferente Pequeno/genética , Ratos , Ratos Sprague-Dawley , Receptores de N-Metil-D-Aspartato/genética
5.
Nutr Metab Cardiovasc Dis ; 23(6): 566-73, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22402061

RESUMO

BACKGROUND AND AIM: The purpose of this study was to evaluate the effects of exercise training on cardiac apoptotic pathways in obesity. METHODS AND RESULTS: Sixteen lean Zucker rats (LZR) and sixteen obese Zucker rats (OZR) of 5-6 months of age as well as the other sixteen obese rats were subjected to treadmill running exercise for 1 h everyday for 3 months (OZR-EX). After exercise training or sedentary status of the rats, the excised hearts from the three groups were measured by heart weight index, H&E staining, TUNEL assays and Western blotting. Cardiac TUNEL-positive apoptotic cells, the protein levels of TNF alpha, Fas ligand, Fas receptors, Fas-associated death domain (FADD), Bad, Bax, activated caspase 8, activated caspase 9, and activated caspase 3 were higher in OZR than those in LZR. The protein levels of TNF alpha, Fas ligand, Fas receptors, FADD, activated caspase 8, and activated caspase 3 (Fas pathway) and the protein levels of Bad, Bax, Bax-to-Bcl2 ratio, activated caspase 9, and activated caspase 3 (mitochondria pathway) were lower in OZR-EX than those in OZR. CONCLUSION: Cardiac Fas-dependent and mitochondria-dependent apoptotic pathways become more activated in obesity. Exercise training can prevent obesity-activated cardiac Fas-dependent and mitochondria-dependent apoptotic pathways. Our findings demonstrate a new therapeutic effect of exercise training to prevent delirious cardiac Fas-mediated and mitochondria-mediated apoptosis in obesity.


Assuntos
Apoptose , Coração/fisiopatologia , Obesidade/fisiopatologia , Condicionamento Físico Animal , Animais , Pressão Sanguínea , Caspase 3/metabolismo , Caspase 9/metabolismo , Ecocardiografia , Proteína Ligante Fas/metabolismo , Proteína de Domínio de Morte Associada a Fas/metabolismo , Masculino , Mitocôndrias Cardíacas/metabolismo , Ratos , Ratos Zucker , Fator de Necrose Tumoral alfa/metabolismo , Proteína X Associada a bcl-2/metabolismo , Receptor fas/metabolismo
7.
Angew Chem Int Ed Engl ; 52(47): 12298-302, 2013 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-24108547

RESUMO

It stems from the magnetism: The extraction of stem/progenitor cells from the brain of live animals is possible using antibodies conjugated to magnetic nanoparticles (Ab-MNPs). The Ab-MNPs are introduced to a rat's brain with a superfine micro-syringe. The stem cells attach to the Ab-MNPs and are magnetically isolated and removed. They can develop into neurospheres and differentiate into different types of cells outside the subject body. The rat remains alive and healthy.


Assuntos
Anticorpos/química , Encéfalo/citologia , Separação Celular/métodos , Nanopartículas de Magnetita/química , Células-Tronco Neurais/citologia , Antígeno AC133 , Animais , Anticorpos/imunologia , Antígenos CD/imunologia , Antígenos CD/metabolismo , Separação Celular/instrumentação , Glicoproteínas/imunologia , Glicoproteínas/metabolismo , Células-Tronco Neurais/metabolismo , Tamanho da Partícula , Peptídeos/imunologia , Peptídeos/metabolismo , Ratos , Medicina Regenerativa
8.
HLA ; 102(3): 343-347, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37376846

RESUMO

HLA genes are the most polymorphic in the human genome. High resolution HLA typing from 13,870 bone marrow donors in Hong Kong was obtained using Next-generation sequencing (NGS) technology. Among the 67 novel alleles identified, official HLA allele names of 50 novel class I alleles (HLA-A, -B, -C) and 8 novel class II alleles (HLA-DRB1, -DQB1) were assigned by the World Health Organization (WHO) Nomenclature Committee for Factors of the HLA System.


Assuntos
População do Leste Asiático , Antígenos de Histocompatibilidade , Humanos , Alelos , População do Leste Asiático/genética , Frequência do Gene , Haplótipos , Sequenciamento de Nucleotídeos em Larga Escala , Antígenos de Histocompatibilidade/genética
9.
Vox Sang ; 102(3): 221-7, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21883272

RESUMO

BACKGROUND AND OBJECTIVES: Miltenberger blood group antigen subtype III (Mi.III) is characterized by expression of a glycophorin B-A-B hybrid (Gp.Mur) on the erythrocyte surface. The two alleles of glycophorin B are substituted with the B-A-B hybrid alleles in homozygous Mi.III (Mi.III(+/+)), and thus, Mi.III(+/+) erythrocytes lack glycophorin B (GPB) and express Gp.Mur only. Because GPB is a major component of the Rh complex on RBCs, in this study, we explored how the absence of GPB might affect Rh expression in Mi.III RBCs. MATERIALS AND METHODS: (1) Mi.III+ RBCs were serologically identified and further differentiated their homozygosity or heterozygosity by immunoblot or direct sequencing. (2) RhD and RhCcEe mRNA was cloned, and their sequences analysed. (3) The expression levels of Rh antigen, Rh-associated glycoprotein (RhAG) and the U antigen in MI.III vs. non-Mi.III RBCs were assessed by flow cytometry and Western blot. RESULTS: Compared with the non-Mi.III samples, the surface expression of the Rh antigen was reduced to 76·4% in Mi.III(+/+) RBCs and 93·6% in Mi.III(+/-). RhAG expression was also significantly reduced in Mi.III(+/+), but not in Mi.III(+/-). The U antigen expression in Mi.III(+/-) was only 14·9% relative to the control RBCs, while GPB was half the level of the controls. The mRNA sequences of Rh polypeptides from Mi.III+ samples were identical to the NCBI reference sequences. CONCLUSION: Substitution of GPB with Gp.Mur significantly reduced the expression of Rh antigen and RhAG on the Mi.III(+/+) erythrocyte membrane. The Mi.III phenotype is predicted to induce considerable structural variations within the band 3/Rh-associated macrocomplexes.


Assuntos
Proteínas Sanguíneas/biossíntese , Membrana Eritrocítica/metabolismo , Regulação da Expressão Gênica/fisiologia , Glicoforinas/biossíntese , Glicoproteínas de Membrana/biossíntese , Sistema do Grupo Sanguíneo Rh-Hr/biossíntese , Feminino , Humanos , Masculino , RNA Mensageiro/biossíntese
11.
Proc Natl Acad Sci U S A ; 106(37): 15961-6, 2009 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-19805236

RESUMO

Hypothalamic magnocellular neurons express either one of the neurohypophysial hormones, vasopressin or oxytocin, along with different neuropeptides or neuromodulators. Axonal terminals of these neurons are generally accepted to release solely the two hormones but not others into the circulation. Here, we show that secretin, originally isolated from upper intestinal mucosal extract, is present throughout the hypothalamo-neurohypophysial axis and that it is released from the posterior pituitary under plasma hyperosmolality conditions. In the hypothalamus, it stimulates vasopressin expression and release. Considering these findings together with our previous findings that show a direct effect of secretin on renal water reabsorption, we propose here that secretin works at multiple levels in the hypothalamus, pituitary, and kidney to regulate water homeostasis. Findings presented here challenge previous understanding regarding the neurohypophysis and could provide new concepts in treating disorders related to osmoregulation.


Assuntos
Água Corporal/fisiologia , Neuro-Hipófise/fisiologia , Secretina/fisiologia , Animais , Sequência de Bases , Primers do DNA/genética , Expressão Gênica , Homeostase/fisiologia , Sistema Hipotálamo-Hipofisário/fisiologia , Imuno-Histoquímica , Rim/fisiologia , Modelos Neurológicos , Sistemas Neurossecretores/fisiologia , Neurotransmissores/genética , Neurotransmissores/fisiologia , Concentração Osmolar , Ratos , Secretina/sangue , Secretina/genética , Vasopressinas/genética , Vasopressinas/fisiologia
12.
Biomed Res Int ; 2022: 9759214, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35996544

RESUMO

[This corrects the article DOI: 10.1155/2021/7640314.].

13.
J Affect Disord ; 308: 221-228, 2022 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-35429539

RESUMO

BACKGROUND: Major Depressive Disorder is a severe and highly disabling mental illness. Almost all self-reported questionnaires have overlooked the interpersonal symptoms of depression which are important across gender and culture. The Multidimensional Depression Assessment Scale (MDAS) developed by Cheung and Power (2012) entails comprehensive emotional, cognitive, somatic, and interpersonal subscales. It addresses the criticism that existing self-report depression scales might not cover sufficient phenomenological heterogeneity of depression. The current study aimed to evaluate the psychometric properties of the MDAS across gender and four major ethnic groups of Caucasian, Black, Asian and Hispanic, including reliability and concurrent validity against the Centre for Epidemiological Studies Depression Scale (CESD) and Patients Health Questionnaire (PHQ-9). It also aimed to establish a stable factor structure across gender and ethnic groups and test the measurement invariance to enhance its potential for clinical use. METHODS: A community sample of 3499 participants from four ethnic groups were recruited via online crowdsourcing sites of Qualtrics and Amazon M Turk. Each individual completed a demographic questionnaire, the MDAS, CESD and PHQ-9. RESULTS: There was good internal consistency (Cronbach's alpha >0.90) and concurrent reliability across gender and ethnic groups. Strict measurement invariance was established for MDAS over a four-factor factor structure corresponding to the four subscales. CONCLUSIONS: The MDAS showed good psychometric properties and measurement invariance of a four-factor structure, suggesting its potential to be used in clinical settings across gender and ethnic groups. LIMITATIONS: Participants all answered the questionnaires in English, which could hinder cultural variations in their expression of symptoms.


Assuntos
Transtorno Depressivo Maior , Etnicidade , Depressão/psicologia , Transtorno Depressivo Maior/diagnóstico , Análise Fatorial , Hispânico ou Latino , Humanos , Psicometria , Reprodutibilidade dos Testes , Inquéritos e Questionários
14.
Kidney Int ; 79(3): 280-7, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-20944548

RESUMO

Body fluid homeostasis is critical for the survival of living organisms and hence is tightly controlled. From initial studies on the effects of secretin (SCT) on renal water reabsorption in the 1940s and recent investigations of its role in cardiovascular and neuroendocrine functions, it has now become increasingly clear that this peptide is an integral component of the homeostatic processes that maintain body fluid balance. This review, containing some of our recent findings of centrally expressed SCT on water intake, focuses on the actions of SCT in influencing the physiological, neuroendocrine, and cardiovascular processes that subserve body fluid homeostasis.


Assuntos
Líquidos Corporais/metabolismo , Secretina/metabolismo , Equilíbrio Hidroeletrolítico , Animais , Sistema Cardiovascular/metabolismo , Ingestão de Líquidos , Comportamento de Ingestão de Líquido , Humanos , Rim/metabolismo , Sistemas Neurossecretores/metabolismo
17.
Biomed Res Int ; 2021: 7640314, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34938810

RESUMO

BACKGROUND: Chronic pruritus is a common and distressing condition that has serious emotional and psychosocial consequences. Due to its subjective nature, self-report questionnaires are widely implemented as cost-effective measures to gauge the severity of chronic pruritus. The current study is aimed at validating the 5-D itch scale in three ethnic groups-Black, Asian, and Hispanic-with the well-validated Itch Numerical Rating Scale (NRS) and Worst Itch NRS (WI-NRS) and developing its cutoff value using receiver operating characteristics (ROC) and inspection of the area under the curve (AUC) across ethnic groups. At the same time, it is aimed at comparing the concurrent prevalence of itch and depression in these populations, who often form ethnic minorities in many countries. The current study addresses the knowledge gap of cultural adaptation of the 5-D pruritus scale for greater usage. METHODS: Community samples of three ethnic groups were recruited from an online platform of Qualtrics and administered the self-report questionnaires of Itch-NRS, 5-D itch scale, and Patient Health Questionnaire-9 (PHQ-9) to measure their pruritus domains, itch intensity, depression screening, and its severity. Informed consent was obtained from all participants. Subgroup analysis was conducted, including concurrent validity and cutoff values compared between each ethnic group. Concurrent prevalence of itch and depression was evaluated using the cutoff value of Itch-NRS and PHQ-9. RESULT: A total of 2323 participants were included in the study. A significant positive correlation (p < 0.001) was found between the Itch-NRS, WI-NRS, and 5-D itch scale. The cutoff value of the 5-D itch scale was established for the three ethnic groups using ROC, with a cutoff value of Itch-NRS as a reference. CONCLUSIONS: The 5-D itch scale has demonstrated sound psychometric properties in three ethnic groups and is closely related to Itch-NRS. The analysis of the cutoff value of the 5-D itch scale suggests that different cutoff values should be considered to reduce the inflation of pruritus severity.


Assuntos
Minorias Étnicas e Raciais/psicologia , Etnicidade/psicologia , Prurido/diagnóstico , Prurido/psicologia , Adulto , Feminino , Humanos , Masculino , Psicometria/métodos , Qualidade de Vida/psicologia , Reprodutibilidade dos Testes , Autorrelato , Índice de Gravidade de Doença , Inquéritos e Questionários
18.
Appl Microbiol Biotechnol ; 87(4): 1221-35, 2010 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-20532758

RESUMO

Living organisms produce a myriad of molecules to protect themselves from fungal pathogens. This review focuses on antifungal proteins from plants and mushrooms, many of which are components of the human diet or have medicinal value. Plant antifungal proteins can be classified into different groups comprising chitinases and chitinase-like proteins, chitin-binding proteins, cyclophilin-like proteins, defensins and defensin-like proteins, deoxyribonucleases, embryo-abundant protein-like proteins, glucanases, lectins, lipid transfer proteins, peroxidases, protease inhibitors, ribonucleases, ribosome-inactivating proteins, storage 2S albumins, and thaumatin-like proteins. Some of the aforementioned antifungal proteins also exhibit mitogenic activity towards spleen cells, nitric oxide inducing activity toward macrophages, antiproliferative activity toward tumor cells, antibacterial activity, and inhibitory activity toward HIV-1 reverse transcriptase. In contrast to the large diversity of plant antifungal proteins, only a small number of mushroom antifungal proteins have been reported. Mushroom antifungal proteins are distinct from their plant counterparts in N-terminal sequence. Nevertheless, some of the mushroom antifungal proteins have been shown to inhibit HIV-1 reverse transcriptase activity and tumor cell proliferation.


Assuntos
Agaricales/metabolismo , Antifúngicos/metabolismo , Tratamento Farmacológico , Proteínas Fúngicas/metabolismo , Proteínas de Plantas/metabolismo , Plantas/metabolismo , Agaricales/química , Agaricales/genética , Animais , Antifúngicos/farmacologia , Antifúngicos/uso terapêutico , Proteínas Fúngicas/farmacologia , Proteínas Fúngicas/uso terapêutico , Fungos/efeitos dos fármacos , Humanos , Proteínas de Plantas/farmacologia , Proteínas de Plantas/uso terapêutico , Plantas/genética , Plantas/microbiologia
19.
Hum Immunol ; 81(10-11): 577-579, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32893027

RESUMO

Next-generation sequencing (NGS) at the HLA-A, -B, -C, -DRB1, -DRB3/4/5, -DQA1, -DQB1, -DPA1, and -DPB1 loci was performed on 5,266 southern Chinese unrelated donors of the Hong Kong Bone Marrow Donor Registry. High-resolution HLA genotypes defined by full sequencing of class I loci and extended coverage of class II loci were attained to determine allele frequencies and estimate haplotype frequencies. This study provides allele and haplotype frequencies on 11 loci estimated for the first time in the Hong Kong Chinese population. These results describe extended haplotypes including the less frequently typed HLA-DPA1, -DPB1 and -DQA1 loci and distinctive haplotype associations. The present data are timely in that they allow the permissible matching in HLA-DPB1 for Chinese patients awaiting haematopoietic stem cell transplantation upon applying the latest requirement of NMDP matching guidelines. Overall, these results provide a useful reference source for population genetics studies, HLA-disease association studies and for improving donor recruitment and selection strategies of bone marrow registries. The allele and haplotype data are available in the Allele Frequencies Net Database under the population name ''Hong Kong Chinese HKBMDR, HLA 11 loci'' and the identifier (AFND3724) [1].


Assuntos
Alelos , Medula Óssea/imunologia , Frequência do Gene , Loci Gênicos , Antígenos HLA/genética , Haplótipos , Sistema de Registros , Doadores não Relacionados , Povo Asiático/genética , Transplante de Medula Óssea , Técnicas de Genotipagem/métodos , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Antígenos de Histocompatibilidade Classe I/genética , Antígenos de Histocompatibilidade Classe II/genética , Teste de Histocompatibilidade/métodos , Hong Kong , Humanos
20.
Lupus ; 18(12): 1082-6, 2009 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19762382

RESUMO

Patients with systemic lupus erythematosus (SLE) frequently received corticosteroid therapy, resulting in osteonecrosis of the femoral head (ONFH). Prior studies demonstrated the effectiveness of extracorporeal shockwave treatment (ESWT) for ONFH.. This study evaluated the effectiveness of ESWT for ONFH in patients with SLE. We studied 39 patients, including 15 patients with SLE (26 hips) and 24 controls (29 hips). To each affected hip we applied ESWT (6000 impulses at 28 kV in a single session). Patients were ambulated with partial weight bearing for 4-6 weeks. The primary endpoint was the need for hip replacement. The secondary endpoints were improvement in hip pain and function and image changes on X-ray and MRI. Patients received total hip replacement in 12% of patients with SLE and in 14% of controls (P = 0.802). There was no statistically significant difference in pain scores (0.86 vs. 0.89; P = 0.467) and function scores (89% vs. 91%; P = 0.194) between patients with SLE and controls. SLE response to ESWT for ONFH is comparable with ONFH in patients without SLE.


Assuntos
Necrose da Cabeça do Fêmur , Ondas de Choque de Alta Energia/uso terapêutico , Lúpus Eritematoso Sistêmico , Adulto , Artroplastia de Quadril , Feminino , Necrose da Cabeça do Fêmur/etiologia , Necrose da Cabeça do Fêmur/patologia , Necrose da Cabeça do Fêmur/terapia , Articulação do Quadril/patologia , Articulação do Quadril/cirurgia , Humanos , Lúpus Eritematoso Sistêmico/complicações , Lúpus Eritematoso Sistêmico/patologia , Masculino , Pessoa de Meia-Idade , Resultado do Tratamento , Adulto Jovem
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