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1.
Hong Kong Med J ; 29(5): 432-442, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37524686

RESUMO

INTRODUCTION: Anaemia is a global public health problem among children. However, few studies have examined anaemia prevalence and risk factors among Chinese children of different ages, particularly in poor rural areas. This study investigated these two aspects among children aged 6 to 23 months in poor rural areas of China. METHODS: This cross-sectional study included 1132 children aged 6 to 23 months in three prefectures of the Qinba Mountains area. A finger prick blood test for haemoglobin and anaemia was conducted, along with household surveys of socio-demographic characteristics, illness characteristics, and feeding practices. Multiple linear and logistic regression analyses were used to determine predictors of anaemia. RESULTS: Overall, 42.6% of children in the study displayed anaemia. Children aged 6 to 11 months had the highest anaemia prevalence (53.6%). Anaemia risk factors differed among age-groups and throughout the overall sample. Bivariate and multivariable regression results showed that continued breastfeeding, any history of formula feeding, and consumption of iron-rich or iron-fortified foods were prominent risk factors for anaemia. However, continued breastfeeding and any history of formula feeding had the greatest impact across age-groups (both P<0.05). CONCLUSION: Anaemia remains a severe public health problem among children aged 6 to 23 months in rural China. Healthy feeding practices, nutritional health knowledge, and nutrition improvement projects are needed to reduce the burden of anaemia among children in rural areas of China.


Assuntos
Anemia , Feminino , Humanos , Criança , Lactente , Prevalência , Estudos Transversais , Anemia/epidemiologia , Fatores de Risco , Ferro , China/epidemiologia , População Rural
3.
Zhonghua Yu Fang Yi Xue Za Zhi ; 54(3): 278-282, 2020 Mar 06.
Artigo em Chinês | MEDLINE | ID: mdl-32187932

RESUMO

Objective: To explore the association of dietary pattern and type 2 diabetes mellitus (T2DM) risk. Methods: In 2013, 3 747 participants from 87 coalmine branches of a large coal mine group in Datong City, Shanxi Province were selected by using a two-stage cluster stratified sampling method. Data on demographic characteristics, smoking, drinking, and family history of diabetes were collected by using a self-made questionnaire, and the International Physical Activity Questionnaire was used to assess the level of physical activity. Physical, glucose and lipid metabolism indicators were measured and subjects were divided into high-risk groups and low-risk groups of T2DM according to the T2DM risk score. Dietary data were collected by using Semi-quantitative Food Frequency Questionnaire, and dietary patterns were derived by using the exploratory factor analysis and cluster analysis. The unconditional logistic regression model was used to assess the association of dietary patterns and T2DM risk. Results: The age of the subjects was(41.48±8.62) years old, and 2 843 of them were males (84.31%). A total of 1 819 subjects were in the high-risk group and 1 553 in the low-risk group. Four dietary patterns, healthy diet, high-salt diet, meats diet, and carbohydrate-rich diet, were identified in this study. The unconditional logistic regression analysis showed that compared with the healthy diet pattern, after the adjustment of demographic characteristics, smoking, and drinking, the OR (95%CI) of T2DM risk in high-salt diet, carbohydrate-rich diet and meats diet patterns was 1.54 (1.26-1.88), 1.80 (1.43-2.28) and 1.20 (0.99-1.46), respectively. Conclusion: High-salt diet and carbohydrate-rich diet were positively associated with T2DM risk, whereas there was no association of meats diet and T2DM risk.


Assuntos
Diabetes Mellitus Tipo 2/etiologia , Dieta/efeitos adversos , Adulto , Estudos Transversais , Diabetes Mellitus Tipo 2/etnologia , Inquéritos sobre Dietas , Carboidratos da Dieta , Açúcares da Dieta , Feminino , Humanos , Modelos Logísticos , Masculino , Carne , Pessoa de Meia-Idade , Fatores de Risco , Cloreto de Sódio na Dieta
4.
Zhonghua Liu Xing Bing Xue Za Zhi ; 38(1): 26-31, 2017 Jan 10.
Artigo em Chinês | MEDLINE | ID: mdl-28100372

RESUMO

Objective: To investigate the effects of mitochondrial DNA (mtDNA) copy number in peripheral blood and related factors on the risk of hypertension in coal miners. Methods: A case-control study was conducted in 378 coal miners with hypertension and 325 healthy coal miners recruited from Datong Coal Mine Group. A standard questionnaire was used to collect their general information, such as demographic characteristics, habits and occupational history. Fluorescence quantitative PCR was performed to detect the copy number of mtDNA. Logistic regression model was applied for identifying the related risk factors of hypertension and analyzing the interaction between mtDNA copy number and risk factors. Results: The prevalence of hypertension of high mtDNA copy number was lower than mtDNA copy numberin 0-5.67 group, but the difference was not statistically significant (P=0.414). Alcohol drinking (OR=1.80, 95% CI: 1.26-2.56), family history of hypertension (OR=1.74, 95% CI: 1.20- 2.50), work shifts (OR=0.69, 95% CI: 0.48-0.99), education level (P=0.012) and family monthly income level (P=0.001) were related to the prevalence of hypertension. There were potential interactions between mtDNA copy number and alcohol drinking, family monthly income level, family history of hypertension, respectively. Alcohol drinking was a risk factor for hypertension [1.77 (1.25-2.50)]. Potential interactions between mtDNA copy number and alcohol drinking reduced the risk of hypertension (OR=1.20, 95% CI: 1.07-1.35). Family history of hypertension was a risk factor for hypertension [1.81(1.26-2.59)]. Potential interactions between mtDNA copy number and family history of hypertension reduced the risk of hypertension (OR=1.24, 95%CI: 1.09-1.41). Family monthly income level was a protect factor for hypertension [0.55(0.46-0.66)]. Potential interactions between mtDNA copy number and family monthly income level increased the protection role of hypertension (OR=0.90, 95% CI: 0.86-0.94). Conclusion: mtDNA copy number variation was not significantly associated with the prevalence of hypertension in coal miners, but mtDNA copy number showed multiplication interaction on the prevalence of hypertension with alcohol drinking, family monthly income level as well as family history of hypertension and made their influences weaken.


Assuntos
Minas de Carvão , Variações do Número de Cópias de DNA , DNA Mitocondrial , Mineradores , Saúde Ocupacional , Consumo de Bebidas Alcoólicas/epidemiologia , Estudos de Casos e Controles , Humanos , Hipertensão/sangue , Hipertensão/epidemiologia , Hipertensão/genética , Modelos Logísticos , Prevalência , Reação em Cadeia da Polimerase em Tempo Real , Fatores de Risco , Inquéritos e Questionários
5.
Zhonghua Wai Ke Za Zhi ; 54(8): 591-5, 2016 Aug 01.
Artigo em Chinês | MEDLINE | ID: mdl-27502132

RESUMO

OBJECTIVE: To summarize the experience of totally thoracoscopic cardiac surgical (TTCS) at congenital heart diseases (CHD) treatment. METHODS: From April 2000 to March 2016, 2 543 patients with CHD underwent TTCS in Department of Cardiovascular Surgery, Xijing Hospital, Fourth Military Medical University, including 957 male and 1 586 female patients. The age ranged from 0.5 to 66.0 years with a mean age of (21±18) years. The body weight ranged from 6 to 118 kg with a mean of (49±30) kg. Patients were diagnosed with echocardiography or transesophagel echocardiography as complex or complicated CHD which was unsuitable for percutaneous procedure. Surgical procedures were performed through 3 holes inserted at the right chest wall, and catheters were placed in the right femoral artery and vein to set up cardiopulmonary bypass.The ascending aorta was cross-clamped with long tailor-made forceps and the myocardium was protected by coronary perfusion with cold crystalloid(blood)cardioplegia. There were 787 cases (from January 2013 to December 2015) were selected to compare with 710 cases underwent conventional thoracotomy over the same period. Statistical analysis was performed by t test, t' test, rank-sum test, χ(2) test and Fisher exact test, respectively. RESULTS: The total death rate and the major complication rate of the operation were 0.35% (9/2 543) and 2.28% (58/2 543), respectively. All patients were followed up 1 to 190 months and the average follow-up time was (75±34) months. No residual shunt or obvious mitral/tricuspid regurgitation was observed, and the patients gained better cardiac function as level Ⅰ to Ⅱ (New York Heart Association classification). There was no significant difference in aorta clamp time, ICU stay, hospital cost, and surgical fatality rate between 787 patients underwent TTCS and 710 conventional thoracotomy. The cardiopulmonary bypass time ((31±20) minuets vs. (40±17) minuets, t'=9.407, P=0.001), operation time ((91±27) minuets vs. ( 102±64) minuets, t'=4.251, P=0.000), hospital stay ((5.3±2.2) d vs. (13.0±4.0) d, t'=45.463, P=0.000), postoperative drainage (M(QR): 33(17) ml vs. 121(53) ml, T=2.632, P=0.000) and major complications (7/787 vs. 23/710, χ(2)=10.49, P=0.001) were significantly reduced and no sternal deformation occurrence (0 vs. 192/710, χ(2)=244.10, P=0.000) in TTCS group. While the cost was higher in TTCS group ((24 000±400) yuan vs. (20 000±400) yuan, t=19.320, P=0.000). CONCLUSION: TTCS is feasible, safe, and minimal invasive for patients with CHD, resulting in quick recovery and good median-long term outcomes.


Assuntos
Procedimentos Cirúrgicos Cardíacos/métodos , Ponte Cardiopulmonar/métodos , Cardiopatias Congênitas/cirurgia , Toracoscopia/métodos , Toracotomia , Adolescente , Adulto , Criança , Pré-Escolar , Ecocardiografia , Feminino , Artéria Femoral , Parada Cardíaca Induzida , Humanos , Tempo de Internação , Masculino , Pessoa de Meia-Idade , Duração da Cirurgia , Resultado do Tratamento , Adulto Jovem
6.
Cell Death Dis ; 6: e1650, 2015 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-25695603

RESUMO

Hypoxia complicates islet isolation for transplantation and may contribute to pancreatic ß-cell failure in type 2 diabetes. Pancreatic ß-cells are susceptible to hypoxia-induced apoptosis. Severe hypoxic conditions during the immediate post-transplantation period are a main non-immune factor leading to ß-cell death and islet graft failure. In this study, we identified the transcription factor Ets-1 (v-ets erythroblastosis virus E26 oncogene homolog 1) as an early response gene against hypoxia-induced apoptosis in pancreatic ß-cells. Hypoxia regulates Ets-1 at multiple levels according to the degree of ß-cell oxygen deprivation. Moderate hypoxia promotes Ets-1 gene transcription, whereas severe hypoxia promotes its transactivation activity, as well as its ubiquitin-proteasome mediated degradation. This degradation causes a relative insufficiency of Ets-1 activity, and limits the transactivation effect of Ets-1 on downstream hypoxic-inducible genes and its anti-apoptotic function. Overexpression of ectopic Ets-1 in MIN6 and INS-1 cells protects them from severe hypoxia-induced apoptosis in a mitochondria-dependent manner, confirming that a sufficient amount of Ets-1 activity is critical for protection of pancreatic ß-cells against hypoxic injury. Targeting Ets-1 expression may be a useful strategy for islet graft protection during the immediate post-transplantation period.


Assuntos
Hipóxia Celular/fisiologia , Células Secretoras de Insulina/citologia , Células Secretoras de Insulina/metabolismo , Proteína Proto-Oncogênica c-ets-1/metabolismo , Animais , Apoptose/genética , Apoptose/fisiologia , Hipóxia Celular/genética , Linhagem Celular , Técnicas In Vitro , Camundongos , Camundongos Endogâmicos C57BL , Mitocôndrias/metabolismo , Proteína Proto-Oncogênica c-ets-1/genética , Ratos , Ratos Sprague-Dawley
7.
J Am Chem Soc ; 135(38): 14229-39, 2013 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-23924376

RESUMO

The photoionization and dissociative photoionization of glycerol are studied experimentally and theoretically. Time-of-flight mass spectrometry combined with vacuum ultraviolet synchrotron radiation ranging from 8 to 15 eV is used to investigate the nature of the major fragments and their corresponding appearance energies. Deuterium (1,1,2,3,3-D5) and (13)C (2-(13)C) labeling is employed to narrow down the possible dissociation mechanisms leading to the major fragment ions (C3H(x)O2(+), C2H(x)O2(+), C2H(x)O(+), CH(x)O(+)). We find that the primary fragmentation of the glycerol radical cation (m/z 92) occurs only via two routes. The first channel proceeds via a six-membered hydrogen-transfer transition state, leading to a common stable ternary intermediate, comprised of neutral water, neutral formaldehyde, and a vinyl alcohol radical cation, which exhibits a binding energy of ≈42 kcal/mol and a very short (1.4 Å) hydrogen bond. Fragmentation of this intermediate gives rise to experimentally observed m/z 74, 62, 44, and 45. Fragments m/z 74 and 62 both consist of hydrogen-bridged ion-molecule complexes with binding energy >25 kcal/mol, whereas the m/z 44 species lacks such stabilization. This explains why water- or formaldehyde-loss products are observed first. The second primary fragmentation route arises from cleaving the elongated C-C bond. Also for this channel, intermediates comprised of hydrogen-bridged ion-molecule complexes exhibiting binding energies >24 kcal/mol are observed. Energy decomposition analysis reveals that electrostatic and charge-transfer interactions are equally important in hydrogen-bridged ion-molecule complexes. Furthermore, the dissociative photoionization of the glycerol dimer is investigated and compared to the main pathways for the monomeric species. To a first approximation, the glycerol dimer radical cation can be described as a monomeric glycerol radical cation in the presence of a spectator glycerol, thus giving rise to a dissociation pattern similar to that of the monomer.


Assuntos
Glicerol/efeitos da radiação , Hidrogênio/química , Cátions , Dimerização , Glicerol/química , Ligação de Hidrogênio , Luz , Conformação Molecular , Teoria Quântica , Eletricidade Estática , Termodinâmica
8.
J Biol Regul Homeost Agents ; 24(2): 207-14, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20487634

RESUMO

The object of this study is to determine the cytokine release from PBMCs exposed to Pd model nanoparticles emitted from catalytic converters. PBMCs of 8 healthy non-atopic women were incubated in the presence of Pd nanoparticles (5-10 nm) or salt (potassium hexa-chloropalladate) 10-5 and 10-6 M. Release of cytokines in supernatant of PBMCs was then determined. In cultures without LPS, IL-10 and IL-17 release from PBMCs was inhibited by Pd salt, while Pd nanoparticles inhibited TNF-alpha and IL-17 release. In LPS-stimulated cultures, release of IFN-gamma, TNF-alpha, IL-10 and IL-17 was inhibited by Pd salt, whereas IFN-gamma release was enhanced and TNF-alpha and IL-17 release was inhibited by Pd nanoparticles. In conclusion, Pd salt inhibits cytokine release, whereas Pd nanoparticles exert modulatory effects enhancing the release of IFN-gamma, a Th1 cytokine typical of delayed allergic reactions. This result is interesting considering the increase of allergic contact dermatitis to Pd in people exposed to Pd nanoparticles in urban environments.


Assuntos
Citocinas/sangue , Leucócitos Mononucleares/fisiologia , Paládio/farmacologia , Adulto , Citocinas/metabolismo , Feminino , Humanos , Interferon gama/sangue , Interferon gama/metabolismo , Interleucina-10/sangue , Interleucina-10/metabolismo , Interleucina-17/sangue , Interleucina-17/metabolismo , Interleucina-5/sangue , Interleucina-5/metabolismo , Leucócitos Mononucleares/efeitos dos fármacos , Leucócitos Mononucleares/metabolismo , Pessoa de Meia-Idade , Seleção de Pacientes , Valores de Referência , Fator de Necrose Tumoral alfa/sangue , Fator de Necrose Tumoral alfa/metabolismo
9.
Oncogene ; 29(27): 3896-907, 2010 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-20453888

RESUMO

HER2/neu (HER2) and cyclin E are important prognostic indicators in breast cancer. As both are involved in cell cycle regulation we analyzed whether there was a direct interaction between the two. HER2 and cyclin E expression levels were determined in 395 breast cancer patients. Patients with HER2-overexpression and high levels of cyclin E had decreased 5-year disease-specific survival compared with low levels of cyclin E (14% versus 89%, P<0.0001). In vitro studies were performed in which HER2-mediated activity in HER2-overexpressing breast cancer cell lines was downregulated by transfection with HER2 small interfering RNA or treatment with trastuzumab. Cyclin E expression levels were determined by western blot analysis, and functional effects analyzed using kinase assays, MTT assays were used to assess cell viability as a marker of proliferation and fluorescence-activated cell sorting analysis was used to determine cell cycle profiles. Decreased HER2-mediated signaling resulted in decreased expression of cyclin E, particularly the low molecular weight (LMW) isoforms. Decreased HER2 and LMW cyclin E expression had functional consequences, including decreased cyclin E-associated kinase activity and decreased proliferation, because of increased apoptosis and an increased accumulation of cells in the G1 phase. In vivo studies performed in a HER2-overexpressing breast cancer xenograft model confirmed the effects of trastuzumab on cyclin E expression. Given the relationship between HER2 and cyclin E, in vitro clonogenic assays were performed to assess combination therapy targeting both proteins. Isobologram analysis showed a synergistic interaction between the two agents (trastuzumab targeting HER2 and roscovitine targeting cyclin E). Taken together, these studies show that HER2-mediated signaling effects LMW cyclin E expression, which in turn deregulates the cell cycle. LMW cyclin E has prognostic and predictive roles in HER2-overexpressing breast cancer, warranting further study of its potential as a therapeutic target.


Assuntos
Neoplasias da Mama/metabolismo , Ciclina E/metabolismo , Receptor ErbB-2/metabolismo , Animais , Anticorpos Monoclonais/farmacologia , Anticorpos Monoclonais/uso terapêutico , Anticorpos Monoclonais Humanizados , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Ciclina E/química , Ciclina E/genética , Regulação para Baixo , Fase G1/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica , Humanos , Camundongos , Camundongos Nus , Peso Molecular , Ligação Proteica , Transdução de Sinais/efeitos dos fármacos , Taxa de Sobrevida , Transcrição Gênica , Trastuzumab
10.
J Appl Microbiol ; 108(4): 1207-16, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19732216

RESUMO

AIMS: Our goal was to identify a novel biosurfactant produced by a marine oil-degrading bacterium. METHODS AND RESULTS: Biosurfactants were produced by Alcanivorax dieselolei strain B-5(T) growing with diesel oil as the sole carbon and energy source. Culture supernatant was first extracted with chloroform/methanol (1:1, v/v), then further purified step by step with a normal phase silica gel column, a Sephadex LH20 gel column and a preparative thin layer plate. The main component was determined to be a lipopeptide; it was chemically characterized with nuclear magnetic resonance, liquid chromatography-quadrupole ion-trap mass spectrometry, amino acid analysis and GC-MS and was found to be a mixture of proline lipids. The monomers of the proline lipids were composed of a proline residue and a fatty acid (C(14:0), C(16:0) or C(18:0)). The critical micelle concentration of the mixed proline lipids was determined to be 40 mg l(-1). Moreover, activity variations in ranges of pH, temperature and salinity were also detected and showed reasonable stability. CONCLUSIONS: Alcanivorax dieselolei B-5 produced a novel linear lipoamino biosurfactant, characterized as a proline lipid. SIGNIFICANCE AND IMPACT OF THE STUDY: A proline lipid was characterized for the first time as a bacterial biosurfactant. This product has potential in both environmental and industrial applications.


Assuntos
Alcanivoraceae/química , Tensoativos/isolamento & purificação , Alcanivoraceae/metabolismo , Aminoácidos/metabolismo , Hidrocarbonetos/metabolismo , Concentração de Íons de Hidrogênio , Lipídeos/química , Lipopeptídeos/química , Tensoativos/metabolismo , Temperatura
11.
Curr Pharm Des ; 12(8): 963-9, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-16533163

RESUMO

We have chemically synthesized several stable analogs of the naturally occurring hepoxilins, 12-LO products derived from arachidonic acid, which we found to have promising actions in a variety of test systems of disease. The analogs, PBTs, afford chemical and biological stability to the hepoxilin molecule. This article reviews some of our latest observations with the PBTs in the areas of inflammation (inhibition of the bleomycin-evoked lung fibrosis in mice in vivo), platelet aggregation (antagonism of the thromboxane receptor in human platelets in vitro) and thrombosis (inhibitors in vivo), and cancer (apoptosis of the human leukemia cell line, K562 in vitro and in vivo). The demonstration that the PBTs are active in vivo suggests that they can serve as a platform for their further development as novel therapeutics in disease.


Assuntos
Ácido 8,11,14-Eicosatrienoico/análogos & derivados , Anti-Inflamatórios/farmacologia , Antineoplásicos/farmacologia , Fibrinolíticos/farmacologia , Ácido 8,11,14-Eicosatrienoico/farmacologia , Ácido 8,11,14-Eicosatrienoico/uso terapêutico , Animais , Anti-Inflamatórios/uso terapêutico , Apoptose/efeitos dos fármacos , Bleomicina , Plaquetas/efeitos dos fármacos , Modelos Animais de Doenças , Humanos , Células K562 , Leucemia Experimental/tratamento farmacológico , Pulmão/efeitos dos fármacos , Pulmão/patologia , Camundongos , Agregação Plaquetária/efeitos dos fármacos , Fibrose Pulmonar/induzido quimicamente , Fibrose Pulmonar/patologia , Fibrose Pulmonar/prevenção & controle
13.
Int J Immunopathol Pharmacol ; 16(2): 139-44, 2003.
Artigo em Inglês | MEDLINE | ID: mdl-12797904

RESUMO

The purpose of our study is to determine the alteration of neurobehavioral parameters, autonomic nervous function and lymphocyte subsets in aluminum electrolytic workers of long-term aluminum exposure. 33 men who were 35.16 +/- 2.95 (mean +/- S.D) years old occupationally exposed to aluminum for 14.91 +/- 6.31 (mean +/- S.D) years. Air Al level and urinary aluminum concentration was measured by means of graphite furnace atomic absorption spectrophotometer. Normal reference group were selected from a flour plant. Neurobehavioral core test battery (NCTB) recommended by WHO was utilized. Autonomic nervous function test battery recommended by Ewing DJ was conducted on subjects. FAC SCAN was used to measure the lymphocyte subsets of peripheral blood. The mean air aluminum level in the workshop was 6.36 mg/m3, ranged from 2.90 to 11.38 mg/m3. Urinary aluminum of the Al electrolytic workers (40.08 +/- 9.36 microgram/mg.cre) was obviously higher than that of control group (26.84 +/- 8.93 m/mg.cre). Neurobehavioral results showed that the scores of DSY, PAC and PA in Al electrolytic workers were significantly lower than those of control group, The score of POMSC, POMSF and SRT among Al exposed workers were significantly augmented in relation to those of control group. Autonomic nervous function test results showed that R-R interval variability of maximum ratio of immediately standing up in Al electrolytic workers were decreased compare with the control group, while the BP-IS, HR-V, HR-DB, R30:15 had no significant change. Peripheral blood lymphocyte subsets test showed that CD4-CD8+ T lymphocyte in Al electrolytic workers increased. This study suggests that Al exposure exerts adverse effects on neurobehavioral performance, especially movement coordination and negative mood, and parasympathetic nervous function; moreover it increase CD4-CD8+ T lymphocyte subsets.


Assuntos
Compostos de Alumínio/intoxicação , Sistema Nervoso Autônomo/efeitos dos fármacos , Sintomas Comportamentais/induzido quimicamente , Sintomas Comportamentais/imunologia , Eletrólise/efeitos adversos , Subpopulações de Linfócitos/efeitos dos fármacos , Exposição Ocupacional/efeitos adversos , Adulto , Compostos de Alumínio/urina , Análise de Variância , Ansiedade/induzido quimicamente , Sistema Nervoso Autônomo/metabolismo , Sintomas Comportamentais/fisiopatologia , Confusão/induzido quimicamente , Humanos , Subpopulações de Linfócitos/metabolismo , Masculino , Pessoa de Meia-Idade , Testes Neuropsicológicos/estatística & dados numéricos
14.
Biomarkers ; 6(5): 381-6, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-23889311

RESUMO

Most squamous cell carcinomas of the oesophagus in low-risk populations are attributable to alcohol and tobacco consumption, but the aetiologic agents in many high-risk populations have yet to be definitively identified. Linxian, China has some of the highest oesophageal cancer rates in the world. Recent studies suggest that an association exists between high-level exposure to carcinogenic polycyclic aromatic hydrocarbons (PAHs), such as benzo[a]pyrene (B[a]P), and the development of oesophageal cancer. The inhabitants of this high-risk region extensively use coal and wood for cooking and heating in unvented stoves, and thus may be exposed to PAHs produced during the incomplete combustion of these fuel sources. High levels of B[a]P were recently detected in staple food samples from Linxian and histopathologic changes that may be associated with PAH exposure have also been identified in oesophagectomy specimens from the region. In an effort to determine whether this high-risk population is exposed to high levels of PAHs, voided urines from non-smokers (n = 22) without occupational exposure were collected and analysed using immunoaffinity chromatography and synchronous fluorescence spectroscopy for 1-hydroxypyrene glucuronide, a PAH metabolite and index biomarker for mixed PAH exposure. The median urine 1-hydroxypyrene glucuronide concentration (2.06 pmol ml(-1)) was equivalent to concentrations detected in current smokers. To the authors' knowledge, this represents the first report of elevated urine 1-hydroxpyrene glucuronide concentrations in Linxian, and the first biologic confirmation that the inhabitants of this rural, non-industrial, high oesophageal cancer risk region are exposed to carcinogenic PAHs.

15.
J Histochem Cytochem ; 48(10): 1411-9, 2000 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-10990494

RESUMO

There are three isoforms of arachidonate 12-lipoxygenase in mammals: platelet, leukocyte, and epidermal types. We found in this study that the leukocyte-type enzyme was present in rat pineal gland, lung, spleen, aorta, adrenal gland, spinal cord, and pancreas, as assessed by RT-PCR. Immunohistochemical analysis showed that the enzyme was localized in macrophages in lung and spleen, alpha-cells of pancreatic islet, zona glomerulosa cells of adrenal cortex, and neuronal cells of spinal cord and superior cervical ganglion. The presence of the 12-lipoxygenase in pancreatic alpha-cells was confirmed by glucagon staining in a consecutive section. We overexpressed the leukocyte-type 12-lipoxygenase cDNA in a glucagon-secreting alphaTC clone 6 cell line that had been established from a transgenic mouse. Glucagon secretion was stimulated by approximately twofold in the 12-lipoxygenase-expressing cells compared to the mock-transfected and original cells. The results suggest that the 12-lipoxygenase of the leukocyte type augments glucagon secretion from pancreatic islets.


Assuntos
Araquidonato 12-Lipoxigenase/metabolismo , Glucagon/metabolismo , Animais , Especificidade de Anticorpos , Araquidonato 12-Lipoxigenase/imunologia , Western Blotting , Linhagem Celular , Imuno-Histoquímica , Ilhotas Pancreáticas/metabolismo , Leucócitos/enzimologia , Macrófagos/metabolismo , Camundongos , Camundongos Transgênicos , Especificidade de Órgãos , Glândula Pineal/enzimologia , RNA Mensageiro/metabolismo , Ratos , Reação em Cadeia da Polimerase Via Transcriptase Reversa
16.
Life Sci ; 68(4): 401-15, 2000 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-11205890

RESUMO

Rats were exposed for ten months to 60 ppm of lead (Pb, as acetate) in drinking water to further assess cardiovascular effects of chronic Pb exposure. At the end of the treatment, mean blood Pb was 3.1+/-0.3 microg/dL in the control rats and 22.8+/-1.2 microg/dL in the Pb-exposed rats (means+/-SE, n=12 in each group); these values were not comparable to those of humans. Pb greatly increased plasma levels of noradrenaline (NA) and adrenaline (A), but not those of L-DOPA and dopamine; monoaminoxidase activity was augmented by Pb, mostly in the aorta and in the liver; the aorta, liver, heart and kidney showed discrete histopathological alterations in the Pb-exposed rats, in which plasma levels of nitric oxide (NO, determined as L-citrulline) were reduced. Pb was able to induce blood hypertension, resulting from increase of cardiac inotropism and, mostly, total peripheral resistance. These data were discussed also in relation to those obtained in our previous studies carried out in rats exposed to Pb in drinking water (15-60 ppm) for periods ranging from five to eighteen months. Pb appeared to increase both sympathetic nerve activity by central mechanisms (thus increasing plasma NA and A) and cyclic adenosine monophosphate (cAMP)-dependent availability of calcium ions (Ca++) for contractile mechanisms in the vascular and cardiac myocells (also through an increased vascular alpha2- and myocardial beta1-adrenoreceptor reactivity). The reduction of plasma NO, contributing to increase vascular resistance and cardiac inotropism, was explained as a result of actions of Pb on enzyme activities concerned with the kallikrein-kinin (KK) and renin-angiotensin-aldosterone (RAA) systems. It was concluded that chronic Pb exposure is able to affect selective neuroendocrine (i.e., catecholamine), au- tacoidal (i.e., KK and RAA) and transductional pathways (i.e., cAMP, NO, Ca++) involved in the cardiovascular function.


Assuntos
Catecolaminas/metabolismo , Intoxicação por Chumbo/metabolismo , Óxido Nítrico/metabolismo , Animais , Catecolaminas/sangue , Dopamina/sangue , Dopamina/metabolismo , Epinefrina/sangue , Epinefrina/metabolismo , Hemodinâmica/efeitos dos fármacos , Chumbo/sangue , Chumbo/farmacocinética , Intoxicação por Chumbo/sangue , Intoxicação por Chumbo/patologia , Masculino , Monoaminoxidase/sangue , Monoaminoxidase/metabolismo , Óxido Nítrico/sangue , Norepinefrina/sangue , Norepinefrina/metabolismo , Ratos , Ratos Sprague-Dawley
17.
Biochim Biophys Acta ; 1438(1): 131-9, 1999 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-10216287

RESUMO

Mouse skin 8-lipoxygenase was expressed in COS-7 cells by transient transfection of its cDNA in pEF-BOS carrying an elongation factor-1alpha promoter. When crude extract of the transfected COS-7 cells was incubated with arachidonic acid, 8-hydroxy-5,9,11, 14-eicosatetraenoic acid was produced as assessed by reverse- and straight-phase high performance liquid chromatographies. The recombinant enzyme also reacted on alpha-linolenic and docosahexaenoic acids at almost the same rate as that with arachidonic acid. Eicosapentaenoic and gamma-linolenic acids were also oxygenated at 43% and 56% reaction rates of arachidonic acid, respectively. In contrast, linoleic acid was a poor substrate for this enzyme. The 8-lipoxygenase reaction with these fatty acids proceeded almost linearly for 40 min. The 8-lipoxygenase was also expressed in an Escherichia coli system using pQE-32 carrying six histidine residues at N-terminal of the enzyme. The expressed enzyme was purified over 380-fold giving a specific activity of approximately 0.2 micromol/45 min per mg protein by nickel-nitrilotriacetate affinity chromatography. The enzymatic properties of the purified 8-lipoxygenase were essentially the same as those of the enzyme expressed in COS-7 cells. When the purified 8-lipoxygenase was incubated with 5-hydroperoxy-6,8,11, 14-eicosatetraenoic acid, two epimers of 6-trans-leukotriene B4, degradation products of unstable leukotriene A4, were observed upon high performance liquid chromatography. Thus, the 8-lipoxygenase catalyzed synthesis of leukotriene A4 from 5-hydroperoxy fatty acid. Reaction rate of the leukotriene A synthase was approximately 7% of arachidonate 8-lipoxygenation. In contrast to the linear time course of 8-lipoxygenase reaction with arachidonic acid, leukotriene A synthase activity leveled off within 10 min, indicating suicide inactivation.


Assuntos
Araquidonato 5-Lipoxigenase/metabolismo , Araquidonato Lipoxigenases/genética , Escherichia coli/genética , Pele/enzimologia , Animais , Araquidonato Lipoxigenases/biossíntese , Ácido Araquidônico/metabolismo , Clonagem Molecular , DNA Complementar/biossíntese , Escherichia coli/enzimologia , Expressão Gênica , Leucotrienos/metabolismo , Camundongos , Especificidade por Substrato
18.
Zhongguo Zhong Xi Yi Jie He Za Zhi ; 18(11): 662-4, 1998 Nov.
Artigo em Chinês | MEDLINE | ID: mdl-11477859

RESUMO

OBJECTIVE: To observe the effect of Chinese herbal medicine on the salivary glands of patients with head and neck cancer during radiotherapy (RT). METHODS: Fifty cases with head and neck cancer were randomly divided into observation group treated with RT plus Chinese herbal medicine and control group treated with RT alone. The level of mouth dryness, the flow and secretion speed of salivary amylase were measured before and during the RT. RESULTS: The severity of mouth dryness increased and the flow and secretion speed of salivary amylase declined during RT. The mouth dryness curve of patients in Chinese medicine group was significantly more flattened than that of the control group after RT. The flow and the secretion speed of salivary amylase of the observation group were significantly higher than those of the control group at 20 Gy, 40 Gy and 60 Gy. CONCLUSION: Chinese herbal medicine used in this study was effective to relieve the severity of mouth dryness and to protect the salivary glands of patients with head and neck cancer during RT.


Assuntos
Medicamentos de Ervas Chinesas/uso terapêutico , Neoplasias Nasofaríngeas/tratamento farmacológico , Neoplasias Nasofaríngeas/radioterapia , Saliva/metabolismo , Glândulas Salivares/efeitos dos fármacos , Adulto , Idoso , Amilases/metabolismo , Antineoplásicos Fitogênicos/uso terapêutico , Carcinoma de Células Escamosas/tratamento farmacológico , Carcinoma de Células Escamosas/radioterapia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Glândulas Salivares/efeitos da radiação
19.
Biochem Biophys Res Commun ; 238(1): 229-33, 1997 Sep 08.
Artigo em Inglês | MEDLINE | ID: mdl-9299484

RESUMO

Rat pineal gland contains a 12-lipoxygenase as demonstrated by the enzyme activity, RNA blot analysis and in situ hybridization. Using rats maintained with 12-h dark and light cycles, dynamic changes of the enzyme in pineal gland were examined. When the crude extract of pineal glands was incubated with arachidonic acid and the reaction products were analyzed by reverse-phase HPLC, the glands obtained from rats in the dark showed a higher 12-lipoxygenase activity than those obtained from rats in the light. The pineal 12-lipoxygenase activity decreased after the light was on at 7 o'clock and reached the lowest level around 16 o'clock. Upon Western blot analysis the amount of 12-lipoxygenase protein in pineal glands was high in the dark and lowest around 16 o'clock. A half life of the enzyme protein was estimated to be approximately 2.8 h in organ culture of rat pineal glands. Northern blot analysis also revealed a higher 12-lipoxygenase mRNA level in pineal glands obtained in the dark than those obtained in the light. Thus, the 12-lipoxygenase of rat pineal glands shows a diurnal fluctuation that is regulated at the transcription level, and may play a certain role in the regulation of neuroendocrine processes of this gland.


Assuntos
Araquidonato 12-Lipoxigenase/metabolismo , Ritmo Circadiano , Glândula Pineal/enzimologia , Animais , Araquidonato 12-Lipoxigenase/genética , Araquidonato 12-Lipoxigenase/fisiologia , Northern Blotting , Western Blotting , Cromatografia Líquida de Alta Pressão , Estabilidade Enzimática , Masculino , Técnicas de Cultura de Órgãos , Glândula Pineal/fisiologia , RNA Mensageiro/biossíntese , Ratos , Ratos Wistar
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