RESUMEN
The COVID-19 continues to spread throughout the world, and local clusters and outbreaks related to overseas imports have occurred in many places in China. Vaccination against COVID-19 is one of the most effective tools to prevent disease, severe illness and death. For vaccines developed and used by China, it is particularly important for scientific and targeted prevention and control to study different outbreak scenarios, to conduct in-depth real-world research on SARS-CoV-2 variants, and to further promote vaccine development and technical reserves. This article commented the effectiveness of COVID-19 vaccine, and prospected the future research on vaccine efficacy, immunization strategy and vaccine development, which provided evidence for optimizing vaccination strategy.
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COVID-19 , COVID-19/prevención & control , Vacunas contra la COVID-19 , Humanos , Pandemias/prevención & control , SARS-CoV-2 , Eficacia de las VacunasRESUMEN
With the expansion of mpox virus infection from endemic to a global epidemic in 2022, the WHO declared that the mpox event constituted a Public Health Emergency of International Concern. Due to the high degree of gene sequence similarity among orthopox viruses and cross-reactive antibodies induced by orthoviruses, smallpox vaccination may affect the immune response induced by mpox virus infection. The analysis of the protective effects of smallpox vaccination against mpox virus infection will help define the focus of prevention and control. In this review, we clarify the protection of the smallpox vaccine against mpox virus infection by analyzing the correlation between smallpox vaccination, immune response status, and clinical data and providing evidence for the prevention, control, and strategies of mpox epidemics.
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Mpox , Vacuna contra Viruela , Viruela , Humanos , Viruela/prevención & control , Viruela/epidemiología , Mpox/tratamiento farmacológico , Vacuna contra Viruela/uso terapéutico , Vacunación , InmunidadRESUMEN
During anoxia/reoxygenation (A/R) injury, intracellular chloride ion concentration ([Cl(-)](i)) homeostasis may play a role in maintaining the normal physiological function of cardiomyocytes. Various chloride transport systems could have influenced the concentration of chloride ion, but what kinds of chloride transport systems could play an important role in cardiomyocytes subjected to A/R injury and its mechanism are unknown. The aim of our study was to clarify the contributions of various chloride transport systems to anoxia/reoxygenation in rat neonatal cardiac myocytes and further to investigate the involved mechanisms. Oxidative stress and redox-sensitive transcription factor (NF-kappaB) activation are believed to play an important role in the A/R injury. To assess whether oxidative stress and NF-kappaB involve [Cl(-)](i) changes resulting in cardiomyocytes injury, the anoxia-reoxygenation (A/R) injury model was successfully established and administered with inhibitors of various chloride transport systems. Administration with Cl(-)-substitution and Cl(-)/HCO(3) (-) exchange inhibitor(SITS) has been shown to produce a protective effect against A/R injury by decreasing [Cl(-)](i) concentration, lipid peroxidation (malondialdehyde (MDA)) levels, and NF-kappaB activity, and by increasing antioxidant enzyme (glutathione peroxidase (GSHPx), superoxide dismutase (SOD), and catalase(CAT)) activity. However, inhibitors for the Cl(-)-channel (9-AC) and Na(+)-K(+)-2Cl(-) co-transporter (bumetanide) had no effects. Our results indicate that Cl(-)/HCO(3) (-) exchange system plays an important role in the cardiocyte A/R injury by influencing [Cl(-)](i) concentration. The protective effects of SITS and Cl(-)-substitution on cardiomyocytes may be due to the attenuation of oxidative stress and inhibition of NF-kappaB activation.
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Cloruros/metabolismo , Daño por Reperfusión Miocárdica/metabolismo , Miocitos Cardíacos/metabolismo , FN-kappa B/metabolismo , Estrés Oxidativo , Ácido 4-Acetamido-4'-isotiocianatostilbeno-2,2'-disulfónico/farmacología , Animales , Antracenos/farmacología , Apoptosis , Bumetanida/farmacología , Catalasa/metabolismo , Hipoxia de la Célula , Supervivencia Celular , Canales de Cloruro/antagonistas & inhibidores , Canales de Cloruro/metabolismo , Antiportadores de Cloruro-Bicarbonato/metabolismo , Productos Lácteos Cultivados , Pruebas de Enzimas , Glutatión Peroxidasa/metabolismo , L-Lactato Deshidrogenasa/metabolismo , Peroxidación de Lípido , Masculino , Daño por Reperfusión Miocárdica/patología , Miocitos Cardíacos/patología , Oxígeno/metabolismo , Cultivo Primario de Células , Transporte de Proteínas , Ratas , Ratas Sprague-Dawley , Especies Reactivas de Oxígeno/metabolismo , Inhibidores del Simportador de Cloruro Sódico y Cloruro Potásico/farmacología , Simportadores de Cloruro de Sodio-Potasio/metabolismo , Superóxido Dismutasa/metabolismoRESUMEN
Apo-1/Fas (CD95) is a transmembrane protein expressed on the cell surface that is involved in apoptosis and plays an important role in the function and regulation of the immune system. Aberrant expression of the Apo-1/Fas gene product has been reported in a number of immune-related disorders, such as autoimmune lymphoproliferative syndrome and systemic lupus erythematosus in humans. Mutations in the coding sequence of the Apo-1/Fas gene have been reported in the former condition, whereas no abnormalities of the gene have been found to account for the increased gene expression noted in SLE. We screened the whole 5' flanking region of the Apo-1/Fas gene encompassing over 2000 bp for mutation(s)/polymorphism(s) using multiplex PCR, single-strand conformation polymorphism (SSCP) analysis and sequencing techniques, and identified two polymorphisms in this region. The first polymorphism is a CG-->CA substitution at -1377 nucleotide position within the silencer region, which neither creates or deletes any restriction enzyme sites but alters the transcription factor SP-1 binding site. This polymorphism is noted in 20% of normal Caucasians. The second polymorphism is an GA-->GG substitution at -670 nucleotide position in the enhancer region that creates a MvaI restriction fragment length polymorphism (RFLP) and abolishes the binding site of nuclear transcription element GAS. The MvaI RFLP is polymorphic with heterozygosity of 52% and the frequency of G and A alleles are 0.49 and 0.51, respectively. The identification and characterisation of these two new polymorphisms, particularly the MvaI RFLP marker, provides new genetic markers and may prove useful for further studies on the regulation of apoptosis mediated by the Apo-1/Fas gene on human chromosome 10q23.
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Polimorfismo de Longitud del Fragmento de Restricción , Regiones Promotoras Genéticas/genética , Receptor fas/genética , Apoptosis/genética , Secuencia de Bases , Desoxirribonucleasas de Localización Especificada Tipo II/metabolismo , Expresión Génica , Genotipo , Humanos , Datos de Secuencia Molecular , Polimorfismo Conformacional Retorcido-SimpleRESUMEN
Apoptosis mediated by the Apo-1/Fas and Fas ligand pathways has been implicated in many disorders, including autoimmunity and tumorigenesis. The recent identification of two polymorphisms on the 5' flanking region of the human Apo-1/Fas gene has provided useful markers for investigation of the genetic contribution of the Apo-1/Fas gene in these diseases. The Mval polymorphism at the -670 nucleotide position is frequent in the normal population, with 51% heterozygosity. The other polymorphism, a result of single nucleotide G-->A substitution at the -1377 position, does not create or delete any restriction enzyme digestion sites. In this paper, we describe a simple and rapid method for detecting the -1377 polymorphism by using allele-specific amplification (ASA). Using the ASA method, the -1377 polymorphism in a normal Caucasian population was characterised. Frequencies of 0.13 and 0.87 for allele A and G, respectively, were observed and the homozygosity of the mutant allele (A) was found in only 2% of the population. We subsequently examined the -1377 polymorphism in sporadic systemic lupus erythematosus (SLE) patients (n = 86). The results showed that both genotype distribution and allele frequencies in SLE patients were similar to that in controls, suggesting that the -1377 promoter polymorphism is unlikely to be associated with SLE susceptibility. The description of this rapid detection method and characterisation of the -1377 polymorphism are useful means for future genetic studies in diseases in which the Fas-mediated apoptosis may be involved.
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Apolipoproteína A-I/genética , Lupus Eritematoso Sistémico/genética , Glicoproteínas de Membrana/genética , Polimorfismo Genético , Adulto , Anciano , Alelos , ADN/análisis , Análisis Mutacional de ADN , Cartilla de ADN/química , Proteína Ligando Fas , Femenino , Amplificación de Genes , Genotipo , Humanos , Masculino , Persona de Mediana Edad , Datos de Secuencia Molecular , Linaje , Reacción en Cadena de la Polimerasa/métodosRESUMEN
A bench scale system integrated with a non-thermal plasma (NTP) and a biotricking filtration (BTF) unit for the treatment of gases containing dimethyl sulfide (DMS) was investigated. DMS removal efficiency in the integrated system was up to 96%. Bacterial communities in the BTF were assessed by PCR-DGGE, which play the dominant role in the biological processes of metabolism, sulfur oxidation, sulfate-reducing and carbon oxidation. The addition of ozone from NTP made microbial community in BTF more complicated and active for DMS removal. The NTP oxidize DMS to simple compounds such as methanol and carbonyl sulfide; the intermediate organic products and DMS are further oxidized to sulfate, carbon dioxide, water vapors by biological degradation. These results show that NTP-BTF is achievable and open new possibilities for applying the integrated with NTP and BTF to odour gas treatment.
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Contaminantes Atmosféricos , Ozono , Gases em Plasma , Sulfuros/análisis , Sulfuros/química , Biodegradación Ambiental , Reactores Biológicos , Carbono/química , Electroforesis en Gel de Gradiente Desnaturalizante , Diseño de Equipo , Filtración , Gases , Metanol/química , Oxígeno/química , Reacción en Cadena de la Polimerasa , Sulfatos/química , Azufre/química , Óxidos de Azufre/química , Factores de TiempoRESUMEN
The assembly of nanocomplexes from bioactive peptides, namely, caseinophosphopeptides (CPPs) and chitosan (CS), at physiological conditions and various CS/CPP mass ratios has been systematically studied using a combination of liquid chromatography-tandem mass spectrometry (LC-MS/MS), turbidimetric titration, dynamic light scattering (DLS), electrophoretic mobility (ζ-potential) measurements, transmission electron microscopy (TEM), and fluorescence spectroscopy. Peptides incorporated with CS forming nanoparticles were prepared and identified using LC-MS/MS. They were characterized by different amounts of clusters of phosphorylated seryl residues. At low salt concentrations, an increase in CS/CPP mass ratio shifted the critical pH(φ1) value, which was designated as the formation of CS/CPP nanocomplexes, as well as pH(max), which represents the neutralization of positive and negative charges at higher pH values. The sizes, charges, morphologies, binding mechanisms, and binding constants of the bioactive peptide-chitosan nanocomplexes were analyzed, and our results suggest that three processes are involved in nanocomplex formation: First, negatively charged CPPs absorb to positively charged CS molecular chains to form intrapolymer nanocomplexes saturated with CPPs (CPPNPs). Subsequently, the negatively charged CPPNPs are bridged by the addition of positively charged CS, resulting in the formation of nearly neutral associative biopolymer complexes. Finally, further addition of excess chitosan breaks down the bridges of associative complexes and causes the formation of positively charged isolated spherical nanocomplexes. The binding between the peptides and CS is mainly driven by electrostatic interactions with a binding constant of K(cs) = 4.6 × 10(4) M(-1). Phosphorylated groups and other negatively charged amino acids, such as aspartic acid (Asp) and glutamic acid (Glu), in the CPPs might be the dominant sites for interaction with -NH(3)(+) groups on the CS molecular chains.
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Quitosano/síntesis química , Nanopartículas/química , Péptidos/síntesis química , Secuencia de Aminoácidos , Quitosano/química , Cromatografía de Gases y Espectrometría de Masas , Microscopía Electrónica de Transmisión , Datos de Secuencia Molecular , Peso Molecular , Tamaño de la Partícula , Péptidos/químicaRESUMEN
BACKGROUND: This study aimed to examine public knowledge, attitudes and behaviors regarding antibiotic use in the community of Hong Kong. METHODS: A cross-sectional phone survey was conducted in 2006 on people aged 18 or older who were uninstitutionalized Hong Kong residents regarding antibiotic use for upper respiratory tract infections (URTIs). RESULTS: A total of 1,002 respondents participated in the survey and 77%, 72% and 85% of the respondents had adequate knowledge, appropriate attitude/belief and behavior on antibiotic use, respectively. Some respondents (26%) believed that antibiotic was needed for symptoms of URTIs if they felt sick enough to seek medical care and 8% would share antibiotic with family members. Eighty-nine (9%) respondents had acquired antibiotic without a prescription. During the most recent episode of URTI, 78% had completed the antibiotic treatment course. Stepwise multiple logistic showed that higher education level and family income were associated with adequate patient knowledge. Male gender was a predictor of poor behavior on antibiotic use. Appropriate belief was associated with tertiary level of education or above. CONCLUSIONS: Over 70% of the present cohort showed adequate knowledge, appropriate attitudes/beliefs and behavior on antibiotic use. Despite a small percent (8%-9%) of respondents reportedly shared and/or self-prescribed antibiotics, this would translate into the practice of half a million people in Hong Kong. Public education programmes should therefore be developed, targeting specific areas of misconceptions, misuse of antibiotic and vulnerable groups at risk of improper use of antibiotics.
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Antibacterianos/uso terapéutico , Conductas Relacionadas con la Salud , Conocimientos, Actitudes y Práctica en Salud , Encuestas Epidemiológicas , Infecciones del Sistema Respiratorio/tratamiento farmacológico , Adulto , Estudios Transversales , Femenino , Hong Kong , Humanos , Masculino , TeléfonoRESUMEN
Small-angle neutron scattering was used to characterize the solution behavior of charged carboxylic acid terminated "cascade" dendrimers (Z-Cascade/methane [4]/3-oxo-6-oxa-2-azaheptylidyne/3-oxo-2-azaheptylidyne/propanoic acids) of third (G3) and fifth (G5) generations as a function of dendrimer concentration, pH, and ionic strength. An increase in dendrimer concentration leads to a single broad peak in the scattering profile arising from interdendrimer interaction. The dissociation of terminal carboxylate groups also gives rise to an interdendrimer interaction peak, which could be suppressed by the addition of excess salt. The results of contrast matching measurements indicate the accumulation of an excess concentration of tetramethylammonium counterions around the surface of these highly charged particles, and the thickness of these counterions lies somewhere between 4 and 6 A. This conclusion is consistent with our previous potentiometric titration (Zhang, H.; et al. J. Phys. Chem. B 1997, 101, 3494) and capillary electrophoresis (Huang, Q. R.; et al. J. Phys. Chem. B 2000, 104, 898) data.
RESUMEN
Systemic lupus erythematosus (SLE) is an autoimmune disease characterised by the production of a large number of autoantibodies. It has been postulated that this may be the result of prolonged longevity of auto-reactive B cells due to defective regulation of programmed cell death (apoptosis). The proto-oncogene bcl-2 is involved in the control of apoptosis in immunocompetent cells, and its over-expression is noted in T and B cells from SLE patients. This study examined the genetic linkage between the bcl-2 gene locus and SLE susceptibility using the affected sib-pair method in SLE families. Seventeen caucasian multiplex families were evaluated. A polymorphic microsatellite marker closely linked to the bcl-2 gene on 18q21.3 was used to determine the bcl-2 genotype. We demonstrated that haplotype sharing among the affected sibling pairs was not statistically different from random (P > 0.5). This suggests that the bcl-2 gene locus does not confer a genetic susceptibility to SLE expression.
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Genes bcl-2 , Lupus Eritematoso Sistémico/genética , Alelos , Mapeo Cromosómico , Susceptibilidad a Enfermedades , Femenino , Haplotipos , Humanos , Masculino , Linaje , Proto-Oncogenes MasRESUMEN
The effect of ginger root (Zingiberis Rhizoma) on gastrointestinal motility was examined based on its ability to enhance charcoal meal transport in mice. Oral administrations of the acetone extract of ginger (which contains volatile oils and bitter substances) at 75 mg/kg, [6]-shogaol at 2.5 mg/kg, or a [6]-, [8]- or [10]-gingerol at 5 mg/kg enhanced the transport of a charcoal meal. The effects of these substances were similar to or slightly weaker than those of metoclopramide and donperidone.
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Condimentos/análisis , Motilidad Gastrointestinal/efectos de los fármacos , Extractos Vegetales/farmacología , Animales , Catecoles/farmacología , Alcoholes Grasos/farmacología , Masculino , RatonesRESUMEN
OBJECTIVE: We looked for an association between the MvaI polymorphism, a recently reported polymorphism on the promoter of the Apo-1/Fas gene, and rheumatoid arthritis (RA) and systemic lupus erythematosus (SLE) patients. METHODS: Two cohorts of Caucasian RA patients (total number = 185) and one cohort of SLE patients (n = 103) were studied. The MvaI polymorphism was typed by polymerase chain reaction and followed by MvaI digestion and gel electrophoresis. RESULTS: A skewed distribution of MvaI genotypes was found in the first cohort of RA patients (n = 103) compared to the controls, as a result of increased MvaI*2 and decreased MvaI*1 homozygosity. This skewed distribution of genotypes was also observed in RA patients with either early onset of disease or with systemic involvement or progressive disease (assessed by the presence of erosions). The frequency of the MvaI*2 allele was significantly increased in female patients (P = 0.035), patients with extra-articular involvement (P = 0.04) and patients with early onset (P < 0.01), compared to the normals. To confirm these findings, the MvaI polymorphism was also examined in a second cohort of RA patients (n = 82). The results in this cohort did not replicate the associations shown in the first cohort of RA patients. Part of this inconsistency could be attributed to different populations and different parameters collected and analysed. In SLE patients, frequencies of MvaI alleles were not statistically different to the controls. However, MvaI*2 homozygosity was significantly higher in SLE patients with photosensitivity (P = 0.03) or oral ulcers (P = 0.01) than in SLE patients without these features. CONCLUSION: The role of the Apo-1/Fas gene promoter MvaI polymorphism in RA and SLE is unclear and further substantiation in larger patient samples is needed.
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Artritis Reumatoide/genética , Lupus Eritematoso Sistémico/genética , Polimorfismo Genético , Regiones Promotoras Genéticas/genética , Receptor fas/genética , Adulto , Anciano , Secuencia de Aminoácidos , Apoptosis , Estudios de Cohortes , Femenino , Genotipo , Humanos , Masculino , Persona de Mediana Edad , Datos de Secuencia Molecular , Trastornos por Fotosensibilidad/etiología , Reacción en Cadena de la PolimerasaRESUMEN
Frontal analysis continuous capillary electrophoresis (FACCE) was carried out for a series of random copolymers of an ionic monomer, sodium 2-(acrylamido)-2-methylpropanesulfonate (AMPS), and a nonionic monomer, acrylamide (AAM). The electropherograms appeared in order of anionic content and were generally sigmoidal, in contrast to that of hyaluronic acid (HA), which was abrupt and discontinuous. This difference could be related to the compositional heterogeneity of the copolymers, completely absent in the biopolymer. Through the range of copolymer composition (10-100% AMPS) the relationship between average mobility and nominal AMPS content could be described by a calibration curve, making it possible to deduce the compositional distribution of copolymer samples.
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Acrilamidas/análisis , Resinas Acrílicas/análisis , Alcanosulfonatos/análisis , Electroforesis Capilar/métodosRESUMEN
It has been reported that an acetone extract of ginger and its fractions have anti-5-HT (5-hydroxytryptamine; serotonin) effects. In the present study, guinea pig ileum, rat stomach fundus and rabbit aortic strips are used in order to determine the constituents of fraction 2 which are responsible for anti-5-HT effect and to examine their pharmacological properties. The analysis of fraction 2-3 indicated that galanolactone, a diterpenoid, is one of the active constituents. In guinea pig ileum, galanolactone inhibited contractile responses to 5-HT with a pIC50 value 4.93. pIC50 value of galanolactone against the response to 2-methyl-5-HT, a selective 5-HT3 agonist, in the presence of methysergide at 1 x 10(-5) M was 5.10. pIC50 values of ICS 205-930, a selective 5-HT3 antagonist, were 5.30 and 7.49, respectively. The concentration-response curve of 5-HT was shown as a biphasic curve and galanolactone caused a selective shift to the right of the second phase. In the same preparations, the pIC50 value of galanolactone and ICS 205-930 against the response to carbamylcholine (CCh) was 4.45 and 4.46. The inhibitory effect of galanolactone on the 5-HT response in the stomach fundus and aortic strips was less than that in the ileum. In addition, in the thoracic aorta precontracted with 50 mM K+, the relaxing effect of galanolactone was about 1/10 of that of papaverine. These results suggest that the anti-5-HT effect of galanolactone, a diterpenoid isolated from ginger, is related to antagonism of 5-HT3 receptors.
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Condimentos/análisis , Diterpenos/farmacología , Antagonistas de la Serotonina/farmacología , Animales , Cobayas , Técnicas In Vitro , Masculino , Músculo Liso/efectos de los fármacos , Músculo Liso Vascular/efectos de los fármacos , Conejos , RatasRESUMEN
The pathogenesis of multiple sclerosis is under strong genetic control involving several or more genes each of modest effect. Whilst the mechanisms underlying the pathogenesis of MS remain unknown, it has been hypothesised that either decreased apoptosis of autoreactive T cells in the CNS, or increased apoptosis of oligodendrocytes may play an important role. The Apo-1/Fas antigen (CD95), the gene for which is located in a chromosomal region showing linkage in MS genome screens, is a critical inducer of apoptosis and studies have shown aberrant expression of this molecule in MS, correlating with a decrease in T cell apoptosis or increase in CNS tissue damage. This study investigated an Mva I polymorphism in the Apo-1/Fas promoter region in a group of 124 Australian patients with relapsing-remitting MS and in 183 normal controls. Whilst there were increases in the Mva I*2 allele in MS individuals overall (59% vs 52%, P not corrected=0.08), and in HLA-DRB1*1501 negative MS patients (62% vs 55%), these were not significantly different from controls. Interactions were investigated between the Mva I alleles and T cell receptor beta chain variable region (TCRBV) germline polymorphisms, with a trend in MS individuals towards a decrease of the Mva I*1 allele when combined with the TCRBV3S1*2 allele (Relative Risk=0.25, P=0.067), and with the TCRBV8S1*1 allele (Relative Risk=0.44, P=0.12). Overall, the findings of this study indicate a possible effect of the Apo-1/Fas promoter Mva I polymorphism in MS susceptibility, which needs to be confirmed in further studies. Multiple Sclerosis (2000) 6 14 - 18
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Desoxirribonucleasas de Localización Especificada Tipo II/genética , Esclerosis Múltiple/genética , Polimorfismo Genético , Regiones Promotoras Genéticas/fisiología , Receptor fas/genética , Alelos , Apoptosis/inmunología , Australia , Autoantígenos/inmunología , Predisposición Genética a la Enfermedad , Genotipo , Mutación de Línea Germinal , Antígenos HLA-DR/genética , Cadenas HLA-DRB1 , Humanos , Esclerosis Múltiple/inmunología , FenotipoRESUMEN
Patients with low bone mineral density (BMD) have a high risk of future fractures, and should be actively considered for treatment to reduce their risk. However, BMD measurements are not widely available in some communities, because of cost and lack of equipment. Simple questionnaires have been designed to help target high-risk women for BMD measurements, thereby avoiding the cost of measuring women at low risk. However, such tools have previously focused on evaluation of non-Asian women. We collected information about numerous risk factors from postmenopausal Asian women in eight countries in Asia using questionnaires, and evaluated the ability of these risk factors to identify women with osteoporosis as defined by femoral neck BMD T-scores < or =-2.5. Multiple variable regression analysis and item reduction yielded a final tool based on only age and body weight. This risk index had a sensitivity of 91% and specificity of 45%, with an area under the curve of 0.79. Previously published risk indices based on larger numbers of variables performed similarly well in this Asian population. Large differences in risk were identified using our index to create three categories: 61% of the high-risk women had osteoporosis, compared with only 15% and 3% of the intermediate- and low-risk women, respectively. The low-risk group represented 40% of all women, for whom BMD measurements are probably not needed unless important risk factors, such as prior nonviolent fracture or corticosteroid use, are present. An existing population-based sample of postmenopausal Japanese women was used to validate our index. In this sample of Japanese women the sensitivity was 98% and specificity was 29%; the low-risk category, for whom BMD is probably unnecessary, represented 25% of all women. We conclude that our index performed well for classifying the risk of osteoporosis among postmenopausal Asian women and applying it would result in more prudent use of BMD technology.
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Osteoporosis Posmenopáusica/diagnóstico , Encuestas y Cuestionarios , Absorciometría de Fotón , Anciano , Anciano de 80 o más Años , Área Bajo la Curva , Asia/etnología , Femenino , Humanos , Modelos Lineales , Persona de Mediana Edad , Análisis Multivariante , Osteoporosis Posmenopáusica/etnología , Valor Predictivo de las Pruebas , Factores de Riesgo , Sensibilidad y EspecificidadRESUMEN
Bone mineral density (BMD) is an important risk factor for osteoporosis and has strong genetic determination. While average BMD differs among major ethnic groups, several important candidate genes have been shown to underlie BMD variation within populations of the same ethnicity. To investigate whether important candidate genes may contribute to ethnic differences in BMD, we studied the degree of genetic differentiation among several important candidate genes between two major ethnic groups: Caucasians and Chinese. The genetic variability of these two populations (1131 randomly selected individuals) was studied at six restriction sites exhibiting polymorphisms of five important candidate genes for BMD: the BsaHI polymorphism of the calcium-sensing receptor (CASR) gene, the SacI polymorphism of the alpha2HS-glycoprotein (AHSG) gene, the PvuII and XbaI polymorphisms of the estrogen receptor alpha (ESR1) gene, the ApaI polymorphism of the vitamin D receptor (VDR) gene, and the BstBI polymorphism of the parathyroid hormone (PTH) gene. The two ethnic groups showed significant allelic and genotypic differentiation of all the polymorphisms studied. The mean FST was 0.103, which significantly differed from zero (P < 0.01). The Chinese population had lower mean heterozygosity (0.331) than the Caucasian one (0.444); the CASR-BsaHI and PTH-BstBI polymorphisms contributed most significantly to this difference. Analysis of the intra- and inter-population variability suggests that various types of natural selection may affect the observed patterns of variation at some loci. If some of the candidate genes we studied indeed underlie variation in BMD, their population differentiation revealed here between ethnic groups may contribute to understanding ethnic difference in BMD.