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2.
Adv Mater ; 30(2)2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29178432

RESUMO

A series of zirconium polyphenolate-decorated-(metallo)porphyrin metal-organic frameworks (MOFs), ZrPP-n (n = 1, 2), featuring infinite ZrIV -oxo chains linked via polyphenolate groups on four peripheries of eclipse-arranged porphyrin macrocycles, are successfully constructed through a top-down process from simulation to synthesis. These are the unusual examples of Zr-MOFs (or MOFs in general) based on phenolic porphyrins, instead of commonly known carboxylate-based types. Representative ZrPP-1 not only exhibits strong acid resistance (pH = 1, HCl) but also remains intact even when immersed in saturated NaOH solution (≈20 m), an exceptionally large range of pH resistance among MOFs. The metallation at the porphyrin core gives rise to materials with enhanced sorption and catalytic properties. In particular, ZrPP-1-Co, with precise and uniform distribution of active centers, exhibits not only high CO2 trapping capability (≈90 cm3 g-1 at 1 atm, 273 K, among the highest in Zr-MOFs) but also high photocatalytic activity for reduction of CO2 into CO (≈14 mmol g-1 h-1 ) and high selectivity over CH4 (>96.4%) without any cocatalyst under visible-light irradiation (λ > 420 nm). Given the strong chemical resistance under extreme alkali conditions, these catalysts can be recycled without appreciable loss of activity. The possible mechanism for photocatalytic reduction of CO2 -to-CO over ZrPP-1-Co is also proposed.

3.
Physiol Res ; 66(4): 567-580, 2017 09 22.
Artigo em Inglês | MEDLINE | ID: mdl-28406700

RESUMO

Numerous countermeasures have been proposed to minimize microgravity-induced physical deconditioning, but their benefits are limited. The present study aimed to investigate whether personalized aerobic exercise based on artificial gravity (AG) mitigates multisystem physical deconditioning. Fourteen men were assigned to the control group (n=6) and the countermeasure group (CM, n=8). Subjects in the CM group were exposed to AG (2 Gz at foot level) for 30 min twice daily, during which time cycling exercise of 80-95 % anaerobic threshold (AT) intensity was undertaken. Orthostatic tolerance (OT), exercise tests, and blood assays were determined before and after 4 days head-down bed rest (HDBR). Cardiac systolic function was measured every day. After HDBR, OT decreased to 50.9 % and 77.5 % of pre-HDBR values in control and CM groups, respectively. Exercise endurance, maximal oxygen consumption, and AT decreased to 96.5 %, 91.5 % and 91.8 % of pre-HDBR values, respectively, in the control group. Nevertheless, there were slight changes in the CM group. HDBR increased heart rate, sympathetic activity, and the pre-ejection period, but decreased plasma volume, parasympathetic activity and left-ventricular ejection time in the control group, whereas these effects were eliminated in the CM group. Aldosterone had no change in the control group but increased significantly in the CM group. Our study shows that 80-95 % AT aerobic exercise based on 2 Gz of AG preserves OT and exercise endurance, and affects body fluid regulation during short-term HDBR. The underlying mechanisms might involve maintained cardiac systolic function, preserved plasma volume, and improved sympathetic responses to orthostatic stress.


Assuntos
Repouso em Cama/métodos , Pressão Sanguínea/fisiologia , Exercício Físico/fisiologia , Gravidade Alterada , Decúbito Inclinado com Rebaixamento da Cabeça/fisiologia , Frequência Cardíaca/fisiologia , Adulto , Humanos , Masculino , Intolerância Ortostática/diagnóstico , Intolerância Ortostática/fisiopatologia , Consumo de Oxigênio/fisiologia , Fatores de Tempo , Simulação de Ausência de Peso/métodos , Adulto Jovem
4.
Small ; 13(17)2017 05.
Artigo em Inglês | MEDLINE | ID: mdl-28256797

RESUMO

This study reports an oriented and homogenous cobalt-metalloporphyrin network (PIZA-1) thin film prepared by liquid phase epitaxial (LPE) method. The thickness of the obtained thin films can be well controlled, and their photocurrent properties can also be tuned by LPE cycles or the introduction of conductive guest molecules (tetracyanoquinodimethane and C60 ) into the PIZA-1 pores. The study of quartz crystal microbalance adsorption confirms that the PIZA-1 thin film with [110]-orientation presents much higher selectivity of benzene over toluene and p-xylene than that of the PIZA-1 powder with mixed orientations. These results reveal that the selective adsorption of volatile organic compounds highly depends on the growth orientations of porphyrin-based metal-organic framework thin films. Furthermore, the work will provide a new perspective for developing important semiconductive sensing materials with improved selectivity of guest compounds.

5.
Guang Pu Xue Yu Guang Pu Fen Xi ; 36(3): 697-701, 2016 Mar.
Artigo em Chinês | MEDLINE | ID: mdl-27400508

RESUMO

A new method based on near-infrared reflectance spectroscopy (NIRS) analysis was explored to determine the content of rice-resistant starch instead of common chemical method which took long time was high-cost. First of all, we collected 62 spectral data which have big differences in terms of resistant starch content of rice, and then the spectral data and detected chemical values are imported chemometrics software. After that a near-infrared spectroscopy calibration model for rice-resistant starch content was constructed with partial least squares (PLS) method. Results are as follows: In respect of internal cross validation, the coefficient of determination (R2) of untreated, pretreatment with MSC+1thD, pretreatment with 1thD+SNV were 0.920 2, 0.967 0 and 0.976 7 respectively. Root mean square error of prediction (RMSEP) were 1.533 7, 1.011 2 and 0.837 1 respectively. In respect of external validation, the coefficient of determination (R2) of untreated, pretreatment with MSC+ 1thD, pretreatment with 1thD+SNV were 0.805, 0.976 and 0.992 respectively. The average absolute error was 1.456, 0.818, 0.515 respectively. There was no significant difference between chemical and predicted values (Turkey multiple comparison), so we think near infrared spectrum analysis is more feasible than chemical measurement. Among the different pretreatment, the first derivation and standard normal variate (1thD+SNV) have higher coefficient of determination (R2) and lower error value whether in internal validation and external validation. In other words, the calibration model has higher precision and less error by pretreatment with 1thD+SNV.


Assuntos
Oryza/química , Sementes/química , Espectroscopia de Luz Próxima ao Infravermelho , Amido/química , Calibragem , Grão Comestível/química , Análise dos Mínimos Quadrados , Modelos Teóricos
6.
Sci Rep ; 5: 15951, 2015 Nov 03.
Artigo em Inglês | MEDLINE | ID: mdl-26526519

RESUMO

The structural and electronic properties for the global minimum structures of medium-sized neutral, anionic and cationic Sin(µ) (n = 20-30, µ = 0, -1 and +1) clusters have been studied using an unbiased CALYPSO structure searching method in conjunction with first-principles calculations. A large number of low-lying isomers are optimized at the B3PW91/6-311 + G* level of theory. Harmonic vibrational analysis has been performed to assure that the optimized geometries are stable. The growth behaviors clearly indicate that a structural transition from the prolate to spherical-like geometries occurs at n = 26 for neutral silicon clusters, n = 27 for anions and n = 25 for cations. These results are in good agreement with the available experimental and theoretical predicted findings. In addition, no significant structural differences are observed between the neutral and cation charged silicon clusters with n = 20-24, both of them favor prolate structures. The HOMO-LUMO gaps and vertical ionization potential patterns indicate that Si22 is the most chemical stable cluster, and its dynamical stability is deeply discussed by the vibrational spectra calculations.

7.
Zhonghua Nan Ke Xue ; 21(4): 300-7, 2015 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-26027095

RESUMO

OBJECTIVE: To investigate the levels of secretions from the prostate and seminal vesicles and their association with the expressions of aquaporins (AQP) in the prostatic tissue and seminal vesicles of castrated rats. METHODS: We randomly divided 18 eight-week-old male SD rats into a control, a castration, and a testosterone (T) replacement group. Four weeks after surgical castration, we detected the plasma T level and measured the volumes of the secretions and the expressions of AQPs 3, 7, and 10 - 12 in the prostate and seminal vesicles of the rats. RESULTS: The plasma T level was significantly lower in the castrated models ([30. 98 ± 28. 84] ng/dl) than in the rats of the control ([700.78 ± 123.8] ng/dl) and T replacement groups ([688.08 ± 132. 47] ng/dl) (P <0. 05). The castration group, in comparison with the control and T replacement groups, showed remarkably reduced ratios of prostatic secretion volume / prostate weight ([11.1 ± 0.30] vs [2.32 ± 0.61] and [2.13 ± 0.56] %, P <0. 05) and seminal vesicle secretion volume / seminal vesicle weight ( [4. 78 ± 1. 97 ] vs [57. 36 ± 11. 86] and [55. 74 ± 7. 21] %, P < 0. 05). Immunohistochemistry revealed the expressions of AQPs 3 and 7 in the epithelial envelop and cytoplasm and that of AQP 11 the in endothelial envelop and cytoplasm of the prostate and seminal vesicles. Western blot exhibited significantly lower expressions of AQPs 3, 7, and 10 - 12 in the prostate and seminal vesicles of the castrated rats than in the animals of the control and T replacement groups (P <0. 05). CONCLUSION: Significant decreases of the secretions from the prostate and seminal vesicles may be related to the reduced expressions of AQPs 3, 7, and 10 - 12 in the prostatic tissue and seminal vesicles in castrated rats.


Assuntos
Aquaporinas/metabolismo , Orquiectomia , Próstata/metabolismo , Glândulas Seminais/metabolismo , Animais , Humanos , Masculino , Distribuição Aleatória , Ratos , Ratos Sprague-Dawley , Testosterona/sangue
8.
J Mol Neurosci ; 54(4): 811-9, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25398668

RESUMO

The single-nucleotide polymorphisms (SNP) rs6943555 in autism susceptibility candidate 2 (AUTS2) has been reported to be significantly associated with alcohol consumption in Europeans. In this study, we identified the SNP in AUTS2 contributing to the genetic susceptibility to heroin dependence. The potential association between heroin dependence and 21 SNPs (rs2270162, rs2851510, rs513150, rs595681, rs210606, rs10237984, rs13228123, rs10235781, rs6969375, rs6943555, rs10251416, rs17141963, rs12669427, rs723340, rs2293507, rs2293508, rs6960426, rs9886351, rs2293501, rs10277450, rs1918425) of AUTS2 was examined in a Chinese Han population using the MassARRAY system. The participants included 426 patients with heroin dependence and 416 healthy controls. Single SNP association, haplotype association, and clinical phenotype association were analyzed. Single SNP association revealed that AA homozygotes of rs6943555 were significantly over-represented in the patients with heroin dependence compared with the control subjects (P=0.0019). The patients with heroin dependence had a significantly higher frequency of the A allele (P=0.0003, odd ratio (OR)=1.429, 95% confidence interval (CI)=1.175-1.738). Strong linkage disequilibrium (LD) was observed in five blocks (D'>0.9). In block 2, significantly more A-A haplotypes (P=0.006 after Bonferroni corrections) and significantly fewer T-A haplotypes (P=0.040) were found in the patients with heroin dependence. The genotype and clinical phenotype correlation study of the rs6943555 carriers showed that the amount of heroin self-injection was lower in the patients with the AA genotype relative to AT+TT genotypes (P<0.01). Our results confirmed that, in addition to heroin consumption, the SNP rs6943555 of AUTS2 may also play an important role in the etiology of heroin dependence.


Assuntos
Dependência de Heroína/genética , Polimorfismo de Nucleotídeo Único , Proteínas/genética , Adulto , Estudos de Casos e Controles , Proteínas do Citoesqueleto , Feminino , Humanos , Masculino , Fatores de Transcrição
9.
Int J Mol Sci ; 15(11): 19406-16, 2014 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-25347278

RESUMO

Schizophrenia (SCZ) is a severe and debilitating mental disorder, and the specific genetic factors that underlie the risk for SCZ remain elusive. The autism susceptibility candidate 2 (AUTS2) gene has been reported to be associated with autism, suicide, alcohol consumption, and heroin dependence. We hypothesized that AUTS2 might be associated with SCZ. In the present study, three polymorphisms (rs6943555, rs7459368, and rs9886351) in the AUTS2 gene were genotyped in 410 patients with SCZ and 435 controls using polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) and forced PCR-RFLP methods. We detected an association between SCZ and the rs6943555 genotype distribution (odds ratio (OR)=1.363, 95% confidence interval (CI): 0.848-2.191, p=0.001). The association remained significant after adjusting for gender, and a significant effect (p=0.001) was observed among the females. In the present study, rs6943555 was determined to be associated with female SCZ. Our results confirm previous reports which have suggested that rs6943555 might elucidate the pathogenesis of schizophrenia and play an important role in its etiology.


Assuntos
Estudos de Associação Genética , Predisposição Genética para Doença , Proteínas/genética , Esquizofrenia/genética , Adulto , Alelos , Estudos de Casos e Controles , Proteínas do Citoesqueleto , Feminino , Frequência do Gene , Ligação Genética , Genótipo , Humanos , Desequilíbrio de Ligação , Masculino , Pessoa de Meia-Idade , Razão de Chances , Polimorfismo de Nucleotídeo Único , Fatores de Transcrição , Adulto Jovem
10.
Exp Physiol ; 99(11): 1499-510, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25172891

RESUMO

Cerebral vasomotor reactivity (CVMR) to changes in arterial carbon dioxide tension (P aCO 2) is assessed during steady-state or transient changes in P aCO 2. This study tested the following two hypotheses: (i) that CVMR during steady-state changes differs from that during transient changes in P aCO 2; and (ii) that CVMR during rebreathing-induced hypercapnia would be blunted when preceded by a period of hyperventilation. For each hypothesis, end-tidal carbon dioxide tension (P ET , CO 2) middle cerebral artery blood velocity (CBFV), cerebrovascular conductance index (CVCI; CBFV/mean arterial pressure) and CVMR (slope of the linear regression between changes in CBFV and CVCI versus P ET , CO 2) were assessed in eight individuals. To address the first hypothesis, measurements were made during the following two conditions (randomized): (i) steady-state increases in P ET , CO 2 of 5 and 10 Torr above baseline; and (ii) rebreathing-induced transient breath-by-breath increases in P ET , CO 2. The linear regression for CBFV versus P ET , CO 2 (P = 0.65) and CVCI versus P ET , CO 2 (P = 0.44) was similar between methods; however, individual variability in CBFV or CVCI responses existed among subjects. To address the second hypothesis, the same measurements were made during the following two conditions (randomized): (i) immediately following a brief period of hypocapnia induced by hyperventilation for 1 min followed by rebreathing; and (ii) during rebreathing only. The slope of the linear regression for CBFV versus P ET , CO 2 (P < 0.01) and CVCI versus P ET , CO 2 (P < 0.01) was reduced during hyperventilation plus rebreathing relative to rebreathing only. These results indicate that cerebral vasomotor reactivity to changes in P aCO 2 is similar regardless of the employed methodology to induce changes in P aCO 2 and that hyperventilation-induced hypocapnia attenuates the cerebral vasodilatory responses during a subsequent period of rebreathing-induced hypercapnia.


Assuntos
Dióxido de Carbono/fisiologia , Circulação Cerebrovascular/fisiologia , Sistema Vasomotor/fisiologia , Adulto , Dióxido de Carbono/metabolismo , Feminino , Humanos , Hipercapnia/fisiopatologia , Hiperventilação/fisiopatologia , Hipocapnia/fisiopatologia , Masculino , Oxigênio/sangue , Respiração , Adulto Jovem
11.
Ultrasound Med Biol ; 40(7): 1420-6, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24768481

RESUMO

The aim of this study was to investigate the feasibility of using high-resolution ultrasonography in the diagnosis of brachial plexus (BP) root lesions. A prospective study of ultrasonographic evaluation of BP nerve roots was performed in 37 patients with BP root lesions (29 with root injuries, 8 with tumors). The pre-operative ultrasonographic findings were compared with the surgical and pathohistological findings. All C5-7 roots were detected by ultrasonography in all patients, whereas 92% (68/74) of C8 and 51% (38/74) of T1 nerve roots were visualized. Among 29 patients with BP root avulsion, partial injuries or totally interrupted BP roots were detected in all patients. Cystic masses and neuromas were detected in 16 and 23 patients, respectively. In 8 patients with BP root tumors, 8 hypo-echoic masses were detected inside or partly outside of intervertebral foramina connecting to nerve roots. Surgical exploration revealed that there were 57 BP root avulsions in 29 patients. However, 2 T1 nerve root avulsions had been missed by pre-operative ultrasonography. Pathohistology revealed that all 8 BP root tumors pre-operatively diagnosed by ultrasonography were schwannomas. High-resolution ultrasonography can provide a convenient and accurate imaging modality for quick diagnosis and location of BP root lesions.


Assuntos
Neuropatias do Plexo Braquial/diagnóstico por imagem , Plexo Braquial/diagnóstico por imagem , Plexo Braquial/lesões , Aumento da Imagem/métodos , Traumatismos dos Nervos Periféricos/diagnóstico por imagem , Neoplasias do Sistema Nervoso Periférico/diagnóstico por imagem , Ultrassonografia/métodos , Adulto , Algoritmos , Diagnóstico Diferencial , Feminino , Humanos , Interpretação de Imagem Assistida por Computador/métodos , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
12.
PLoS One ; 9(1): e87247, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24498053

RESUMO

Metabotropic glutamate receptor subtype 3 (mGluR3, encoded by GRM3) plays important roles in the pathophysiology of schizophrenia, depression, and drug dependence. GRM3 polymorphisms were reported to be associated with prefrontal activity, cognitive shifting, and memory capability in healthy subjects, as well as susceptibility to schizophrenia and depression. The goal of this study was to replicate the association of GRM3 with schizophrenia and depression and to explore GRM3's potential association with heroin dependence (HD) in a Chinese population. Seventeen SNPs throughout the GRM3 gene were genotyped using MALDI-TOF within the MassARRAY system, and the allele and genotype distributions were compared between 619 healthy controls and 433 patients with schizophrenia, 409 patients with major depression, and 584 unrelated addicts. We found that GRM3 polymorphisms modulate the susceptibility to HD but do not significantly influence the risk for schizophrenia or depression. An increased risk of HD was significantly associated with the minor alleles of two GRM3 SNPs, including the T allele of rs274618 (Odds ratio (OR) = 1.631, 95% confidence interval (95%CI): 1.317-2.005), the T allele of rs274622 (OR = 1.652, 95% CI: 1.336-2.036), compared with the major alleles. The addicts carrying the minor allele of rs274618 or rs274622 had a shortened duration for transition from first use to dependence (DTFUD) in comparison to homozygote for major allele (P<0.0001 for each SNP using log rank test). Additionally, a 6-SNP haplotype within 5' region of the GRM3 including the minor alleles of the two aforementioned SNPs was significantly associated with an increased risk of HD (P = 0.00001, OR = 1.668, 95% CI: 1.335-2.084). Our data indicated that GRM3 polymorphisms do not contribute to genetic susceptibility to schizophrenia and depression, but they confer an increased risk of HD in a Chinese population.


Assuntos
Transtorno Depressivo/genética , Predisposição Genética para Doença/genética , Dependência de Heroína/genética , Polimorfismo de Nucleotídeo Único , Receptores de Glutamato Metabotrópico/genética , Esquizofrenia/genética , Adolescente , Adulto , Povo Asiático/genética , China , Transtorno Depressivo/etnologia , Feminino , Frequência do Gene , Predisposição Genética para Doença/etnologia , Genótipo , Dependência de Heroína/etnologia , Humanos , Desequilíbrio de Ligação , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Esquizofrenia/etnologia , Adulto Jovem
13.
Alzheimers Dement ; 10(2): 162-70, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23871763

RESUMO

BACKGROUND: To determine if global brain hypoperfusion and oxygen hypometabolism occur in patients with amnestic mild cognitive impairment (aMCI). METHODS: Thirty-two aMCI and 21 normal subjects participated. Total cerebral blood flow (TCBF), cerebral metabolic rate of oxygen (CMRO2), and brain tissue volume were measured using color-coded duplex ultrasonography (CDUS), near-infrared spectroscopy (NIRS), and MRI. TCBF was normalized by total brain tissue volume (TBV) for group comparisons (nTCBF). Cerebrovascular resistance (CVR) was calculated as mean arterial pressure divided by TCBF. RESULTS: Reductions in nTCBF by 9%, CMRO2 by 11%, and an increase in CVR by 13% were observed in aMCI relative to normal subjects. No group differences in TBV were observed. nTCBF was correlated with CMRO2 in normal controls, but not in aMCI. CONCLUSIONS: Global brain hypoperfusion, oxygen hypometabolism, and neurovascular decoupling observed in aMCI suggest that changes in cerebral hemodynamics occur early at a prodromal stage of Alzheimer's disease, which can be assessed using low-cost and bedside-available CDUS and NIRS technology.


Assuntos
Encéfalo/irrigação sanguínea , Circulação Cerebrovascular/fisiologia , Disfunção Cognitiva/sangue , Disfunção Cognitiva/patologia , Oxigênio/metabolismo , Idoso , Encéfalo/patologia , Ecocardiografia Doppler , Feminino , Hemodinâmica , Humanos , Imageamento por Ressonância Magnética , Masculino , Entrevista Psiquiátrica Padronizada , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Espectroscopia de Luz Próxima ao Infravermelho
14.
Hypertension ; 62(5): 973-9, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24041946

RESUMO

The validity of using transcranial Doppler measurement of cerebral blood flow velocity (CBFV) to assess cerebral autoregulation (CA) still is a concern. This study measured CBFV in the middle cerebral artery using transcranial Doppler and volumetric cerebral blood flow (CBF) in the internal carotid artery (ICA) using color-coded duplex ultrasonography to assess CA during steady-state changes in mean arterial pressure (MAP). Twenty-one healthy adults participated. MAP was changed stepwise by intravenous infusion of sodium nitroprusside and phenylephrine. Changes in CBFV, CBF, cerebrovascular resistance (CVR=MAP/CBF), or cerebrovascular resistance index (CVRi=MAP/CBFV) were measured to assess CA by linear regression analysis. The relationship between changes in ICA diameter and MAP was assessed. All values were normalized as percentage changes from baseline. Drug-induced changes in MAP were from -26% to 31%. Changes in CBFV and CVRi in response to MAP were linear, and the regression slopes were similar between middle cerebral artery and ICA. However, CBF in ICA remained unchanged despite large changes in MAP. Consistently, a steeper slope of changes in CVR relative to CVRi was observed (0.991 versus 0.804; P<0.05). The ICA diameter changed inversely in response to MAP (r=-0.418; P<0.05). These findings indicate that CA can be assessed with transcranial Doppler measurements of CBFV and CVRi in middle cerebral artery. However, it is likely to be underestimated when compared with the measurements of CBF and CVR in ICA. The inverse relationship between changes in ICA diameter and MAP suggests that large cerebral arteries are involved in CA.


Assuntos
Pressão Arterial/fisiologia , Velocidade do Fluxo Sanguíneo/fisiologia , Circulação Cerebrovascular/fisiologia , Homeostase/fisiologia , Adulto , Pressão Arterial/efeitos dos fármacos , Velocidade do Fluxo Sanguíneo/efeitos dos fármacos , Artérias Cerebrais/diagnóstico por imagem , Artérias Cerebrais/efeitos dos fármacos , Artérias Cerebrais/fisiologia , Circulação Cerebrovascular/efeitos dos fármacos , Homeostase/efeitos dos fármacos , Humanos , Nitroprussiato/farmacologia , Fenilefrina/farmacologia , Ultrassonografia Doppler Transcraniana , Vasoconstritores/farmacologia , Vasodilatadores/farmacologia
15.
J Cereb Blood Flow Metab ; 33(8): 1190-6, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23591649

RESUMO

Physical activity may influence cerebrovascular function. The objective of this study was to determine the impact of life-long aerobic exercise training on cerebral vasomotor reactivity (CVMR) to changes in end-tidal CO2 (EtCO2) in older adults. Eleven sedentary young (SY, 27±5 years), 10 sedentary elderly (SE, 72±4 years), and 11 Masters athletes (MA, 72±6 years) underwent the measurements of cerebral blood flow velocity (CBFV), arterial blood pressure, and EtCO2 during hypocapnic hyperventilation and hypercapnic rebreathing. Baseline CBFV was lower in SE and MA than in SY while no difference was observed between SE and MA. During hypocapnia, CVMR was lower in SE and MA compared with SY (1.87±0.42 and 1.47±0.21 vs. 2.18±0.28 CBFV%/mm Hg, P<0.05) while being lowest in MA among all groups (P<0.05). In response to hypercapnia, SE and MA exhibited greater CVMR than SY (6.00±0.94 and 6.67±1.09 vs. 3.70±1.08 CBFV1%/mm Hg, P<0.05) while no difference was observed between SE and MA. A negative linear correlation between hypo- and hypercapnic CVMR (R(2)=0.37, P<0.001) was observed across all groups. Advanced age was associated with lower resting CBFV and lower hypocapnic but greater hypercapnic CVMR. However, life-long aerobic exercise training appears to have minimal effects on these age-related differences in cerebral hemodynamics.


Assuntos
Atletas , Circulação Cerebrovascular/fisiologia , Hipercapnia/fisiopatologia , Hipocapnia/fisiopatologia , Músculo Liso Vascular/fisiopatologia , Comportamento Sedentário , Adulto , Idoso , Envelhecimento/fisiologia , Análise de Variância , Dióxido de Carbono/sangue , Interpretação Estatística de Dados , Eletrocardiografia , Feminino , Frequência Cardíaca/fisiologia , Hemodinâmica/fisiologia , Humanos , Hipercapnia/diagnóstico por imagem , Hipocapnia/diagnóstico por imagem , Masculino , Ultrassonografia Doppler Transcraniana
16.
Eur J Appl Physiol ; 112(4): 1295-305, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21786130

RESUMO

Changes of venous compliance may contribute in part to postflight orthostatic intolerance. The purpose of the present study was to determine whether intermittent artificial gravity exposure with ergometric exercise could prevent venous compliance changes in the lower limbs due to simulated weightlessness. Twelve healthy male volunteers were exposed to simulated microgravity for 4 days of head-down bed rest (HDBR). Six subjects were randomly loaded 1.0-2.0 Gz intermittent artificial gravity (at foot level) with 40 W of ergometric workload every day (countermeasure group, CM). The six others served as the control (CON group). Venous compliance was estimated by measuring the corresponding change of cross-sectional area (CSA) of popliteal vein at each minute of various venous occlusion pressure stages. Basal CSA was significantly lower after bed rest in the control group, and preserved in the countermeasure group. The percent increase in the CSA of CON group was significantly greater almost at each minute of various venous cuff pressures after bed rest than before. Compliance of popliteal vein of CON group was significant greater when 40, 60 and 80 mmHg cuff pressure applied after bed rest than before of CON group. In conclusions, a 4-day simulated weightlessness leads to increase of popliteal venous compliance; centrifuge-induced artificial gravity with ergometric exercise can prevent enhancement of popliteal venous compliance due to 4-day head-down tilt bed rest, the effect of the countermeasure on compliance might involve changes in venous filling and changes in venous structure.


Assuntos
Repouso em Cama/efeitos adversos , Terapia por Exercício , Gravidade Alterada , Decúbito Inclinado com Rebaixamento da Cabeça/efeitos adversos , Intolerância Ortostática/prevenção & controle , Veia Poplítea/fisiopatologia , Análise de Variância , Pressão Sanguínea , China , Complacência (Medida de Distensibilidade) , Ergometria , Frequência Cardíaca , Humanos , Masculino , Intolerância Ortostática/diagnóstico por imagem , Intolerância Ortostática/etiologia , Intolerância Ortostática/fisiopatologia , Veia Poplítea/diagnóstico por imagem , Fatores de Tempo , Ultrassonografia , Simulação de Ausência de Peso , Adulto Jovem
17.
Brain Res ; 1420: 106-13, 2011 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-21955727

RESUMO

Deficits in dopamine transmission at D1 receptors in the PFC are implicated in schizophrenia. Genetic polymorphisms in functional regions of DRD1 have a plausible role in modulating the risk of schizophrenia. In order to evaluate the role of DRD1 polymorphisms as a risk factor for schizophrenia, we performed a detailed analysis of possible functional single nucleotide polymorphisms (SNPs) in regulatory and coding regions of DRD1. Nine SNPs were identified by DNA sequencing in 20 patients with schizophrenia. Then 385 cases and 350 healthy control subjects were genotyped using the nine SNPs (rs4867798, rs686, rs1799914, rs4532 rs5326, rs265981, rs10078714, rs10063995, rs10078866). Statistically significant differences were observed in the allelic or genotypic frequencies of the rs686 and rs10063995 polymorphism in the DRD1 gene. A significantly lower risk of schizophrenia was associated with the G allele and AG+GG genotype of rs686 (OR (G allele)=0.632, 95%CI (G allele): 0.470-0.849; OR (AG+GG genotype)=0.578, 95%CI (AG+GG genotype): 0.416-0.803) compared with the A allele and AA genotype, respectively. And a significantly increased risk of schizophrenia was associated with the T allele of rs10063995 (OR=1.446, 95%CI: 1.125-1.859) compared with the G allele. The haplotype analysis indicated the G-T variant containing the T allele of rs10063995 is a risk for schizophrenia (P=0.005, OR=1.467, 95%CI: 1.123-1.917). These data suggest that DRD1 gene polymorphisms confer susceptibility to schizophrenia, and also support the notion that dysfunction of DRD1 is involved in the pathophysiological process of schizophrenia.


Assuntos
Predisposição Genética para Doença , Polimorfismo de Nucleotídeo Único , Receptores de Dopamina D1/genética , Esquizofrenia/genética , Adulto , Alelos , Intervalos de Confiança , Feminino , Estudos de Associação Genética , Genótipo , Humanos , Masculino , Razão de Chances , Adulto Jovem
18.
Zhonghua Yi Xue Yi Chuan Xue Za Zhi ; 28(4): 427-31, 2011 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-21811986

RESUMO

OBJECTIVE: To investigate the relationship between the -308G/A, -857C/T and -1031T/C of tumor necrosis factor alpha gene (TNF- alpha), -174G/C and -572C/G of interleukin-6 gene (IL-6) polymorphisms and schizophrenia. METHODS: Genomic DNA was isolated from the venous blood leukocytes of 346 unrelated patients with schizophrenia and 323 healthy unrelated individuals (control group). All of the polymorphisms were genotyped by PCR-restriction fragment length polymorphisms (PCR-RFLP). Genotype and allele frequencies were analyzed by SPSS13.0 software. RESULTS: There were significant differences in both allele and genotype frequencies of -857C/T of TNF-alpha gene between the schizophrenia and control groups (P< 0.05). The allele T of -857C/T in schizophrenia group was significantly higher than that in control group (chi-square was 9.414, P=0.002, OR=1.511, 95%CI:1.160-1.969). In addition, there were significant differences in the positive and negative syndrome scale (PANSS) total score and negative symptoms between the patients with different -857C/T genotypes, and the negative symptom score of TT genotype was significantly higher than that of CC genotype (P<0.05). CONCLUSION: There is an association between -857C/T of TNF-alpha gene and schizophrenia, individuals with T allele of -857C/T are susceptible to schizophrenia, and there is an association between -857C/T and negative symptom score.


Assuntos
Interleucina-6/genética , Polimorfismo Genético/genética , Regiões Promotoras Genéticas/genética , Esquizofrenia/genética , Fator de Necrose Tumoral alfa/genética , Adulto , Estudos de Casos e Controles , Feminino , Frequência do Gene , Genótipo , Humanos , Masculino , Fenótipo , Reação em Cadeia da Polimerase , Polimorfismo de Fragmento de Restrição , Adulto Jovem
19.
Ultrasound Med Biol ; 37(8): 1196-203, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21645961

RESUMO

The goal of this study was to prospectively investigate the feasibility of preoperative ultrasonography evaluation in the differentiation between pre- and postganglionic traumatic brachial plexus lesions. Two expert radiologists employed ultrasonography to observe the morphology of the brachial plexus in 23 patients with suspected traumatic brachial plexus lesions and 40 healthy volunteers. The detection rate was 100% (126/126) for the C5 through C7 nerve roots and upper and middle trunks and three fascicles, 84% (106/126) for the C8 roots and the lower trunks and 64% (81/126) for T1 roots in all subjects. Surgical inspections found 58 lesions in 23 patients (40 preganglionic lesions and 18 postganglionic lesions). Ultrasonography detected most of the brachial plexus lesions (56/58) but misjudged two preganglionic and two postganglionic lesions. The rate of differentiation was 93% (52/56). This study demonstrated that ultrasonography is a useful but experience-dependent supplemental imaging technique for preoperative diagnosis of brachial plexus lesions and differentiation between pre- and postganglionic brachial plexus lesions.


Assuntos
Neuropatias do Plexo Braquial/diagnóstico por imagem , Plexo Braquial/lesões , Gânglios Espinais/lesões , Adulto , Plexo Braquial/diagnóstico por imagem , Neuropatias do Plexo Braquial/cirurgia , Diagnóstico Diferencial , Estudos de Viabilidade , Feminino , Gânglios Espinais/diagnóstico por imagem , Humanos , Cuidados Intraoperatórios , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Monitorização Intraoperatória , Estudos Prospectivos , Resultado do Tratamento , Ultrassonografia
20.
J Appl Physiol (1985) ; 111(2): 376-81, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21617082

RESUMO

This study explored a novel method for measuring cerebrovascular impedance to quantify the relationship between pulsatile changes in cerebral blood flow (CBF) and arterial pressure. Arterial pressure in the internal or common carotid artery (applanation tonometry), CBF velocity in the middle cerebral artery (transcranial Doppler), and end-tidal CO(2) (capnography) were measured in six young (28 ± 4 yr) and nine elderly subjects (70 ± 6 yr). Transfer function method was used to estimate cerebrovascular impedance. Under supine resting conditions, CBF velocity was reduced in the elderly despite the fact that they had higher arterial pressure than young subjects. As expected, cerebrovascular resistance index was increased in the elderly. In both young and elderly subjects, impedance modulus was reduced gradually in the frequency range of 0.78-8 Hz. Phase was negative in the range of 0.78-4.3 Hz and fluctuated at high frequencies. Compared with the young, impedance modulus increased by 38% in the elderly in the range of 0.78-2 Hz and by 39% in the range of 2-4 Hz (P < 0.05). Moreover, increases in impedance were correlated with reductions in CBF velocity. Collectively, these findings demonstrate the feasibility of assessing cerebrovascular impedance using the noninvasive method developed in this study. The estimated impedance modulus and phase are similar to those observed in the systemic circulation and other vascular beds. Moreover, increases in impedance in the elderly suggest that arterial stiffening, besides changes in cerebrovascular resistance, contributes to reduction in CBF with age.


Assuntos
Envelhecimento/fisiologia , Circulação Cerebrovascular/fisiologia , Resistência Vascular/fisiologia , Adulto , Idoso , Pressão Sanguínea/fisiologia , Eletrocardiografia , Feminino , Análise de Fourier , Frequência Cardíaca/fisiologia , Humanos , Masculino , Pessoa de Meia-Idade , Fluxo Sanguíneo Regional/fisiologia , Ultrassonografia Doppler Transcraniana , Adulto Jovem
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