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1.
Phys Rev Lett ; 129(15): 156401, 2022 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-36269973

RESUMO

Chiral materials have attracted significant research interests as they exhibit intriguing physical properties, such as chiral optical response, spin-momentum locking, and chiral induced spin selectivity. Recently, layered transition metal dichalcogenide 1T-TaS_{2} has been found to host a chiral charge density wave (CDW) order. Nevertheless, the physical consequences of the chiral order, for example, in electronic structures and the optical properties, are yet to be explored. Here, we report the spectroscopic visualization of an emergent chiral electronic band structure in the CDW phase, characterized by windmill-shaped Fermi surfaces. We uncover a remarkable chirality-dependent circularly polarized Raman response due to the salient in-plane chiral symmetry of CDW, although the ordinary circular dichroism vanishes. Chiral Fermi surfaces and anomalous Raman responses coincide with the CDW transition, proving their lattice origin. Our Letter paves a path to manipulate the chiral electronic and optical properties in two-dimensional materials and explore applications in polarization optics and spintronics.

2.
Zhonghua Xin Xue Guan Bing Za Zhi ; 44(10): 885-890, 2016 Oct 24.
Artigo em Chinês | MEDLINE | ID: mdl-27903376

RESUMO

Objective: To observe the prevalence and distribution of ideal cardiovascular health metrics in middle-aged men living in Su-Xi-Chang region and explore the relationship between health behavior and health factors. Methods: A total of 27 824 middle-aged men, who took part in health examination in the Center for Healthcare Management, Taihu Rehabilitation Hospital of Jiangsu Province from January 2014 to June 2015, were enrolled in this cross-sectional study. The ideal cardiovascular health metrics were defined by the American Heart Association criteria with minor modification in that the amount of vegetable intake was replaced by salt intake. The prevalence and distribution of ideal cardiovascular health metrics as well as the association between ideal cardiovascular health metrics and health factors were analyzed in this cohort. Results: The body mass index in the whole cohort was (25.1±3.0) kg/m2, waist circumference was (87.3±8.42) cm; the percent of subjects with all seven ideal cardiovascular health metrics was only 0.5% (n=133). The highest proportion of ideal metric was total cholesterol (68.5%, n=19 056), followed by fasting glucose (66.9%, n=18 616), body mass index (50.2%, n=13 963), physical exercise (45.6%, n=12 697), smoking (40.3%, n=11 216), blood pressure (22.5%, n=6 257) and salt intake (15.6%, n=4 351). The proportion of ideal cardiovascular health metrics reduced gradually and the proportion of poor cardiovascular health metrics status increased gradually with aging(χ2=106.746, P=0.000). The total cholesterol level of non-smokers was significantly lower than that of smokers(F=8.571, P=0.000); total cholesterol, blood pressure and fasting glucose levels increased in proportion with increasing body mass index(all P<0.01); total cholesterol and fasting blood glucose of subjects with regular active physical exercise were significantly lower than those with inactive physical exercise(all P<0.01); total cholesterol and blood pressure of subjects with high salt intake were significantly higher than those with low salt intake(all P<0.01). Conclusions: The proportion of subjects with ideal cardiovascular health metrics is very low in middle-aged men living in Su-Xi-Chang region, and the downtrend with poor cardiovascular health metrics increases with aging. Overweight or obese, smoking, high salt diet and poor control of blood pressure are the major cardiovascular risk factors in this cohort.


Assuntos
Doenças Cardiovasculares , Povo Asiático , Glicemia , Pressão Sanguínea , Determinação da Pressão Arterial , Colesterol , Estudos Transversais , Exercício Físico , Nível de Saúde , Humanos , Masculino , Pessoa de Meia-Idade , Sobrepeso , Prevalência , Fatores de Risco , Fumar , Estados Unidos
3.
Parasite Immunol ; 37(7): 333-9, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25809087

RESUMO

The association between potential long-term effects of previous schistosome infection (PSI) and the development of metabolic syndrome remains unknown. Therefore, we aimed to evaluate the association between them. Participants were from regions which were all reportedly heavily endemic for S. japonicum in China 40 years ago. One thousand five hundred and ninety-seven men were enrolled. Among these, 465 patients with PSI were selected as study subjects and 1132 subjects served as controls. We found PSI significantly correlated with lower prevalences of metabolic syndrome and its components, including central obesity, hypertriglyceridemia and low high-density lipoprotein cholesterol, which indicates that the potential long-term effects of PSI may reduce the risk of metabolic syndrome. However, further studies are needed to investigate the protective immune effects of PSI.


Assuntos
Síndrome Metabólica/epidemiologia , Schistosoma japonicum/imunologia , Esquistossomose/epidemiologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Animais , China/epidemiologia , Humanos , Lipoproteínas HDL/sangue , Masculino , Pessoa de Meia-Idade , Prevalência , Schistosoma japonicum/patogenicidade , Esquistossomose/imunologia , Inquéritos e Questionários , Tempo
4.
J Formos Med Assoc ; 98(1): 11-8, 1999 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-10063268

RESUMO

Polymorphisms of human leukocyte antigens (HLA) are important in transplantation medicine, anthropologic studies, and paternity testing. We investigated the polymorphisms of HLA classes I and II in the Taiwanese population by means of serologic typing and polymerase chain reaction (PCR) analysis with sequence-specific primers. We calculated the HLA-A, -B, and -C gene frequencies in 673 Taiwanese subjects and the HLA-DRB1, and HLA-DQB1 gene frequencies in 204 subjects with available DNA samples. Haplotype frequencies and linkage-disequilibrium were analyzed on the basis of these data. The common HLA class I antigens were A11 (gene frequency, 34.9%), A2 (29.3%), A24 (15.8%), and A33 (9.8%); B60 (21.9%), B46 (13.1%), B58 (9.7%), and B13 (8.5%); and Cw1 (18.8%), Cw7 (15.3%), and Cw10 (10.7%). The common HLA-DRB1 and HLA-DQB1 alleles were DRB1*12 (15.2%), DRB1*09 (15.2%), DRB1*08 (12.0%), and DRB1*04 (12.0%); and DQB1*0301 (23.5%), DQB1*0303 (15.2%), DQB1*0601 (14.5%), and DQB1*02 (10.8%). The common two-locus haplotypes were A2-B46 (frequency, 9. 7%), A11-B60 (9.6%), and A33-B58 (6.8%); DRB1*09-DQB1*0303 (14.9%), DRB1*12-DQB1*0301 (14.2%), and DRB1*08-DQB1*0601 (10.7%). This study is the first to report the gene frequencies of HLA-DQB1 alleles and the common HLA-DR-DQ haplotypes among Taiwanese. Comparison of our results with those from two other Chinese populations in mainland China reveals that Taiwanese are more closely related to southern Han than to northern Han Chinese.


Assuntos
Antígenos HLA/genética , Polimorfismo Genético , China/etnologia , Frequência do Gene , Haplótipos , Humanos , Taiwan
5.
Biosci Biotechnol Biochem ; 59(12): 2239-43, 1995 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-8611746

RESUMO

The keratinase produced by Bacillus licheniformis PWD-1 was induced by feather powder. Maximal enzyme production could be achieved by culturing in a medium containing 1% hammer-milled feather powder (100 mesh) at 45 degrees C for 30 h. Maximal growth of PWD-1 was achieved at 50 degrees C, and maximal enzyme induction was at 45 degrees C. The molecular mass and isoelectric point of this enzyme were 31.4 kDa and 8.5, respectively. This enzyme was stable from pH 5 to 12. The optimal reaction pHs for feather powder and casein were 8.5 and 10.5 to 11.5, respectively. The optimal reaction temperature was 50 degrees C to 55 degrees C. The relative activity of this enzyme toward casein, feather powder, keratin, elastin, and collagen was 100:52:41:18:7, and 100:56:32:3 for Suc-AAPL-pNA, Suc-AAPF-pNA, Suc-AAPM-pNA, and Suc-AAVA-pNA (Suc, succinyl; pNA, p-nitrophenylanilide).


Assuntos
Bacillus/enzimologia , Plumas/metabolismo , Peptídeo Hidrolases/biossíntese , Sequência de Aminoácidos , Animais , Técnicas Bacteriológicas , Galinhas , Humanos , Concentração de Íons de Hidrogênio , Recém-Nascido , Dados de Sequência Molecular , Peptídeo Hidrolases/metabolismo , Temperatura
6.
Leuk Res ; 17(5): 463-70, 1993 May.
Artigo em Inglês | MEDLINE | ID: mdl-8501973

RESUMO

Lymphoblast colony-culture of adult acute lymphoblastic leukemia (ALL) was studied to explore its clinical implication. Among 13 marrow cultures from ALL patients with full-blown disease, 11 developed leukemic colonies. A type of colony, very similar to a lymphoblastic colony and possibly T-cell in origin, could be found in four cultures of the six control marrows. To minimize the difficulty in differentiating a leukemic blast colony and a normal lymphocyte colony, based solely on morphology, a quantitative approach was used. Since both the mean of blast colony count and the mean of blast percentage of leukemic marrow were significantly higher than those of the control group, mean value plus two standard deviations of the control group were defined arbitrarily as upper normal limits. The defined normal range was then used to examine the relationship between results of the cultures and clinical outcome for the ALL patients. Early relapse or incomplete remission following chemotherapy could be predicted in four patients by these quantitative colony-culture assays 0.5-2 months before full-blown disease. The low colony count and low blast percentage in the colony-culture assay of the fifth patient is compatible with the clinical observation of continuous remission. One culture, growing clusters only, had an increased blast percentage; this correlated well with cytogenetic relapse two months later. In summary, the quantitative colony-culture assay could detect morphologically unidentifiable leukemic cells in ALL patients with early relapse or incomplete remission. This quantitative colony-culture system, though not ultrasensitive in the detection of minimal residual leukemic cells, was of potential value as a prognostic assay.


Assuntos
Medula Óssea/patologia , Transformação Celular Neoplásica/patologia , Linfócitos/patologia , Leucemia-Linfoma Linfoblástico de Células Precursoras/patologia , Adolescente , Adulto , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Leucemia-Linfoma Linfoblástico de Células Precursoras/tratamento farmacológico , Ensaio Tumoral de Célula-Tronco
7.
J Nucl Med ; 28(6): 1055-7, 1987 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-3585496

RESUMO

The presence of normal biliary flow was established in a patient with an indwelling hepatic catheter placed to drain an intrahepatic cyst cavity with the use of sequential hepatobiliary scintiscans. In the initial study drainage was demonstrated from the indwelling catheter; when the catheter was clamped, drainage was observed in the native biliary system. Serial biliary scintigraphy not only confirmed the patency of the hepatobiliary system, but served as a guide in the removal of the intrahepatic catheter.


Assuntos
Cateteres de Demora , Colestase/cirurgia , Drenagem , Colestase/diagnóstico por imagem , Colestase/etiologia , Cistos/complicações , Cistos/cirurgia , Humanos , Iminoácidos , Hepatopatias/complicações , Hepatopatias/cirurgia , Masculino , Pessoa de Meia-Idade , Compostos Organometálicos , Cintilografia , Disofenina Tecnécio Tc 99m , Coloide de Enxofre Marcado com Tecnécio Tc 99m
8.
J Nucl Med ; 28(3): 315-8, 1987 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-3102702

RESUMO

Iodine-131 MIBG scintigraphy may be used to determine the presence or absence of metastases to the appendicular skeleton in malignant pheochromocytoma and neuroblastoma. Normal bones show no uptake of [131I]MIBG and the joints are seen as photon-deficient areas surrounded by background muscle activity. Discrete concentrations of radioactivity in bone are often seen in patients with malignant pheochromocytoma and neuroblastoma. Bone marrow involvement in neuroblastoma may be indicated by diffuse uptake of [131I]MIBG or focal accumulation at the metaphyses. Uncommonly, bone involvement may not be displayed by the [131I]MIBG images. Since conventional bone scanning agents may also fail to detect these tumors, skeletal scintigraphy with both [131I]MIBG and [99mTc]MDP is necessary to reliably stage malignant pheochromocytoma and neuroblastoma.


Assuntos
Neoplasias das Glândulas Suprarrenais/diagnóstico por imagem , Neoplasias Ósseas/diagnóstico por imagem , Radioisótopos do Iodo , Iodobenzenos , Neuroblastoma/diagnóstico por imagem , Feocromocitoma/diagnóstico por imagem , 3-Iodobenzilguanidina , Braço , Neoplasias Ósseas/secundário , Humanos , Perna (Membro) , Neuroblastoma/secundário , Feocromocitoma/secundário , Cintilografia , Contagem Corporal Total
9.
Clin Nucl Med ; 11(12): 851-4, 1986 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-3815982

RESUMO

I-131 metaiodobenzylguanidine (I-131 MIBG) is a well established imaging agent that reliably detects pheochromocytoma. In some patients, however, I-131 MIBG may fail to localize pheochromocytoma. I-123 MIBG has several potential advantages over I-131 MIBG, and these advantages may enable locating pheochromocytomas which have eluded other techniques, including I-131 MIBG imaging. A patient with primary extra-adrenal pheochromocytoma is described who illustrates the superiority of I-123 MIBG for the imaging of pheochromocytoma.


Assuntos
Radioisótopos do Iodo , Iodobenzenos , Neoplasias Renais/diagnóstico por imagem , Feocromocitoma/diagnóstico por imagem , 3-Iodobenzilguanidina , Adulto , Feminino , Humanos , Cintilografia
10.
J Nucl Med ; 27(7): 1138-42, 1986 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-3723189

RESUMO

Iodine-123-4-amino-3-iodobenzylguanidine ([123I]AIBG), an analog of 123I metaiodobenzylguanidine ([123I]MIBG), has an advantage in having a more rapid and simple synthesis. This, combined with animal data that suggested a greater affinity of the new radiopharmaceutical for the autonomic innervation of the myocardium led us to study the biodistribution of [123I]AIBG in three men with metastatic pheochromocytoma. In all instances, [123I]AIBG revealed the same metastatic deposits shown by [123I]MIBG. Iodine-123 AIBG uptake, however, was greater than [123I]MIBG in lung, gut, and spleen. These higher backgrounds may pose diagnostic problems in some cases.


Assuntos
Neoplasias das Glândulas Suprarrenais/diagnóstico por imagem , Radioisótopos do Iodo , Iodobenzenos , Feocromocitoma/secundário , 3-Iodobenzilguanidina , Adulto , Humanos , Iodobenzenos/metabolismo , Masculino , Pessoa de Meia-Idade , Feocromocitoma/diagnóstico por imagem , Cintilografia , Distribuição Tecidual
11.
Ration Drug Ther ; 11(5): 1-6, 1977 May.
Artigo em Inglês | MEDLINE | ID: mdl-866664
16.
Arch Intern Med ; 135(5): 668-72, 1975 May.
Artigo em Inglês | MEDLINE | ID: mdl-210730

RESUMO

The response of plasma glucose and insulin to infusion of glucose and of epinephrine plus propranolol were examined in normal subjects and in two patients with surgically proven insulin-secreting islet cell tumors. The plasma immunoreactive insulin concentration in the two patients was both inappropriate and independent of the plasma glucose concentration. Their insulin secretion was neither increased by physiologic stimulants nor decreased by pharmacologic inhibitors of insulin secretion. There are diagnostic uses for these data as well as theoretical implications. We propose a physiological approach to establish the diagnosis of insulin-secreting islet cell tumors.


Assuntos
Adenoma de Células das Ilhotas Pancreáticas/metabolismo , Glicemia/metabolismo , Insulina/metabolismo , Neoplasias Pancreáticas/metabolismo , Adenoma de Células das Ilhotas Pancreáticas/cirurgia , Humanos , Masculino , Pessoa de Meia-Idade , Pancreatectomia , Neoplasias Pancreáticas/cirurgia
17.
J Lab Clin Med ; 85(4): 566-73, 1975 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-1120928

RESUMO

Dopamine-beta-hydroxylase (DBH), an enxyme catalyzing the final step in the synthesis of norepinephrine, is released with norepinephrine on stimulation of the sympathetic nervous system. In this study an enzymatic colorimetric method was used to assay serum DBH activity in 196 individuals of whom 169 were either the parents or children in 29 families. We examined the association of DBH with age and with hypertension and the faamilial pattern of distribution of serum DBH activity. Serum DBH activity was highest in te groups 10 to 14, 40 to 49, and over 60 years. There was no significant difference in serum DBH activity between normal subjects and individuals with hypertension in any age group. tfurthermore, there was no significant correlation of mean blood pressure with serum DBH activity with or without correction of DBH for age differences; Highly significant correlations of serum DBH activity were found in sibling-sibling pairs and in mean parent-child pairs. No significant correlations were found for father-mother pairs. These observations suggest that the contribution of heredity is more important that shared environment in determining the familial pattern of distribution of serum DBH activity. Serum DBH activity did not have a bimodal distribution in the population. Noevidence was found for a maternal influence or for sex linkage in the transmission of this trait. Our data, derived from this study restricted to families with only two generations, are not adequate to specify with confidence the mode of inheritance of DBH activity in the general population.


Assuntos
Dopamina beta-Hidroxilase/sangue , Genética Médica , Adolescente , Adulto , Idoso , Envelhecimento , Pressão Sanguínea , Criança , Pré-Escolar , Feminino , Humanos , Hipertensão/sangue , Hipertensão/enzimologia , Hipertensão/genética , Masculino , Pessoa de Meia-Idade , Pais
19.
J Clin Invest ; 49(12): 2151-60, 1970 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-5480843

RESUMO

A technique was devised for a more accurate measurement than has been heretofore possible of one of the factors responsible for hyperglycemia in the complex syndrome of diabetes. This factor is termed impedance and represents the tissues' insensitivity or resistance to insulin-mediated glucose uptake. It was measured by use of steady-state exogenous insulin and glucose infusions during a period of pharmacological suppression of endogenous insulin secretion. Endogenous new glucose production was also inhibited. Impedance as calculated is a direct function of steady-state glucose concentrations, since exogenous insulin concentrations were similar in all studies. Two groups of normal weight subjects were studied. One had maturity onset latent diabetes, and the other (matched for age, weight, and per cent adiposity) was normal. Impedance was closely reproducible in the same individual and remained relatively constant during prolonged infusions. The diabetics had average infusion glucose concentrations (and thus impedance) 68% higher than the normal group, and it is of note that their previously measured glucose intolerance differed by a similar degree; that is, the diabetic's intolerance (as defined by mean weighted plasma glucose response after oral glucose) was 52% greater than that of the normal individuals.


Assuntos
Diabetes Mellitus/metabolismo , Glucose/metabolismo , Insulina/metabolismo , Adulto , Antígenos , Glicemia , Isótopos de Carbono , Complicações do Diabetes , Antagonismo de Drogas , Epinefrina/administração & dosagem , Feminino , Glucose/administração & dosagem , Teste de Tolerância a Glucose , Humanos , Hiperglicemia/etiologia , Injeções Intravenosas , Insulina/administração & dosagem , Insulina/sangue , Fígado/metabolismo , Masculino , Métodos , Pessoa de Meia-Idade , Propranolol/administração & dosagem , Fatores de Tempo
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