Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 12 de 12
Filtrar
1.
Biomed Environ Sci ; 36(1): 10-23, 2023 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-36650678

RESUMO

Objective: This study assesses the impact of iodine-rich processed foods and dining places on the iodine nutritional status of children. Methods: School-aged children (SAC) in seven provinces in China were selected by school-based multi-stage sampling. Urinary iodine, salt iodine, and thyroid volume (TVOL) were determined. Questionnaires were used to investigate dining places and iodine-rich processed foods. The water iodine was from the 2017 national survey. Multi-factor regression analysis was used to find correlations between variables. Results: Children ate 78.7% of their meals at home, 15.1% at school canteens, and 6.1% at other places. The percentage of daily iodine intake from water, iodized salt, iodine-rich processed foods, and cooked food were 1.0%, 79.2%, 1.5%, and 18.4%, respectively. The salt iodine was correlated with the urinary iodine and TVOL, respectively (r = 0.999 and -0.997, P < 0.05). The iodine intake in processed foods was weakly correlated with the TVOL (r = 0.080, P < 0.01). Non-iodized salt used in processed foods or diets when eating out had less effect on children's iodine nutrition status. Conclusion: Iodized salt remains the primary source of daily iodine intake of SAC, and processed food has less effect on iodine nutrition. Therefore, for children, iodized salt should be a compulsory supplement in their routine diet.


Assuntos
Iodo , Estado Nutricional , Humanos , Criança , Estudos Transversais , Cloreto de Sódio na Dieta/análise , China , Água
4.
Neurotoxicol Teratol ; 47: 96-101, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25446012

RESUMO

BACKGROUND: A systematic review and meta-analysis of published studies on developmental fluoride neurotoxicity support the hypothesis that exposure to elevated concentrations of fluoride in water is neurotoxic during development. METHODS: We carried out a pilot study of 51 first-grade children in southern Sichuan, China, using the fluoride concentration in morning urine after an exposure-free night; fluoride in well-water source; and dental fluorosis status as indices of past fluoride exposure. We administered a battery of age-appropriate, relatively culture-independent tests that reflect different functional domains: the Wide Range Assessment of Memory and Learning (WRAML), Wechsler Intelligence Scale for Children-Revised (WISC-IV) digit span and block design; finger tapping and grooved pegboard. Confounder-adjusted associations between exposure indicators and test scores were assessed using multiple regression models. RESULTS: Dental fluorosis score was the exposure indicator that had the strongest association with the outcome deficits, and the WISC-IV digit span subtest appeared to be the most sensitive outcome, where moderate and severe fluorosis was associated with a digit span total score difference of -4.28 (95% CI -8.22, -0.33) and backward score with -2.13 (95% CI -4.24, -0.02). CONCLUSIONS: This pilot study in a community with stable lifetime fluoride exposures supports the notion that fluoride in drinking water may produce developmental neurotoxicity, and that the dose-dependence underlying this relationship needs to be characterized in detail.


Assuntos
Transtornos Cognitivos/epidemiologia , Transtornos Cognitivos/etiologia , Intoxicação por Flúor/complicações , Intoxicação por Flúor/epidemiologia , Criança , China/epidemiologia , Feminino , Humanos , Masculino , Testes Neuropsicológicos , Avaliação de Resultados em Cuidados de Saúde , Projetos Piloto , Análise de Regressão , Estudos Retrospectivos
5.
Guang Pu Xue Yu Guang Pu Fen Xi ; 32(4): 1057-60, 2012 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-22715784

RESUMO

In the present paper, AgNO3 and KI were used as raw materials synthesize silver iodide nanowire bundles in the condition of nonionic surfactant polyethylene glycol (PEG-400) at room temperature. XRD, TEM and SEM techniques were used to characterize the silver iodide structure and morphology. The results indicated that the product was one-dimensional silver iodide nanowire bundles with diameters of 80-100 nm and lengths of 20 microm, and the length-diameter ratio was greater than 200. In the forming process of silver iodide nanowire bundles, PEG-400 surfactant was used as soft template agent, which induced the product nanocrystalline along a particular direction and directional orderly growth so as to generate nanowire bundles. This method with a simple operation and low cost eliminated the influence of water on the reaction process.

6.
Guang Pu Xue Yu Guang Pu Fen Xi ; 31(11): 2981-6, 2011 Nov.
Artigo em Chinês | MEDLINE | ID: mdl-22242500

RESUMO

The method of CTMAB-Al(3+)-OFLX ternary complex fluorescence microscopic imaging technique was established for the determination of ofloxacin based on the capillary effect of solvent on solid supports, and the concentration in the serum after the chicken was burdened with ofloxacin tablet, the concentration in the human urines and the percentage composition in the honeies, ofloxacin tablets and eye-drops were measured with satisfaction, respectively. In the presence of pH 9. 50 NH3-NH4Cl buffer solution and PVA-124, CTMAB-Al(3+)-OFLX ternary complex can form a self-ordered ring on the hydrophobic supports with the diameter of 1.63 mm and its ring belt width of 50 microm. When a 0.20 microL droplet was spotted, the fluorescence intensity of the ring had a favorable linear relation (r = 0.999 2) with the drug concentration in the range of 3.30 x 10(-13) - 1.65 x 10(-12) mol x ring(-1) (0.60-2.98 mg x L(-1)) and the limit of detection can reach 4.10 x 10(-15) mol x ring(-1) (7.41 microg x L(-1)) with three times of signal to noise ratio. This method has been applied to the average concentration of ofloxacin in the chicken serum with the recovery of 96.4%-101.2% after two hours of being burdened with ofloxacin tablet. Then the technique was applied to the determination of ofloxacin in the three healthy volunteer's urines after oral administration with recovery of 98.2% - 106.%. It was found that the concentrations of ofloxacin in urines were the highest after three hours of taking medicine; the result was similar to reports in the literature. The residues of ofloxacin in three different honey samples were satisfactorily determined with the recoveries of 98.2% - 106.1%, and RSD was less than 2.3%. The contents of active constituent in tablet samples and eye-drops sample were determined with recoveries of 93.5%-101.5% and 95.8%-104.2%, and RSD was 3.5% and 3.6%, respectively, which were similar to marked values.


Assuntos
Microscopia de Fluorescência , Ofloxacino/análise , Animais , Galinhas , Fluorescência , Mel/análise , Humanos , Carne/análise , Ofloxacino/urina , Imagem Óptica , Comprimidos
7.
Zhonghua Er Ke Za Zhi ; 45(12): 927-31, 2007 Dec.
Artigo em Chinês | MEDLINE | ID: mdl-18339283

RESUMO

OBJECTIVE: To investigate the variance and drug resistance of pathogenic bacteria isolated from children with infectious diseases seen between 2001 and 2006 in Chengdu area. METHODS: A total of 2888 pathogenic bacterial strains isolated from children in Chengdu Children's Hospital from 2001 to 2006 were analyzed. Tests were performed according to the guidelines of National Committee for Clinical Laboratory Standards (NCCLS) of the United States. RESULT: (1) Of the 2888 strains, 1845 (63.9%) were Gram negative bacteria. The main pathogenic bacteria included Escherichia coli (Ec, 718 strain, 24.9%), Hemophilus (H, 476 strain, 16.5%), Streptococcus pneumoniae (Sp, 412 strain, 14.3%), Klebsiella pneumoniae (Kp, 369 strain, 12.8%), Staphylococcus aureus (Sa, 353 strain, 12.2%), Staphylococcus epidermidis (Se, 278 strain, 9.6%), Pseudomonas aeruginosa (Pa, 146 strain, 5.1%) and other non-zymocyte (Onz, 136 strain, 4.7%). (2) The common pathogens found in blood specimen were 158 strain, which included Se (78 strain, 49.4%), Ec (23 strain, 14.6%), Kp (17 strain, 10.8%), Sa (14 strain, 8.9%), Onz (14 strain, 8.9%), Sp (7 strain, 4.4%) and Pa (5 strain, 3.2%). (3) The number of common pathogens isolated from patients with lower respiratory tract infection was 2018, including Ec (441 strains, 21.9%), H (430 strains, 21.3%), Sp (368 strains, 18.2%), Kp (253 strains, 12.5%), Sa (207 strains, 10.3%), Se (149 strains, 7.3%), Pa (97 strains, 4.8%) and Onz (73 strains, 3.6%). (4) There were 120 strains of common pathogens isolated from urine specimens, including Ec (78 strains, 65%), Kp (25 strains, 20.8%), Onz (7 strains, 5.8%), Pa (5 strains, 4.2%) and Se (5 strains, 4.2%). (5) There were 497 strains of common pathogens found in pus specimens, including Ec 167 strains, (33.6%), Sa (126 strains, 25.4%), Se (46 strains, 9.3%), H (44 strains, 8.9%), Onz (37 stains, 7.4%), Kp (31 strains, 6.2%), Sp (26 strains, 5.2%) and Pa (20 strain, 4.0%). The trend of drug resistance of pathogenic bacteria to antibiotics deteriorated. The proportion of methicillin-resistant Staphylococcus aureus (MRSA) was 6.7% and the methicillin-resistant coagulase-negative Staphylococci (MRCNS) rate was 20% in 2001 - 2003. The total proportion of extended-spectrum beta-lactamase stains (ESBL(S)) in Ec and Kp was 21.8%, and the rate of beta-lactamase production stains of Hemophilus influenzae (Hi) was 19.4% in 2001 - 2003.The proportion of MRSA was 17.2% and the MRCNS rate was 70.2%, the total proportion of ESBL(S) in Ec and Kp was 43.8%, and the rate of beta-lactamase producing stains of Hi was 39.7% in 2004 - 2006. CONCLUSION: The distribution of common pathogenic bacteria seen in Chengdu Children's Hospital has changed and the trend of drug resistance of pathogenic bacteria to antibiotics deteriorated in recent three years. Regionally monitoring the changes in pathogenic bacteria and the trend of drug resistance to antibiotics is paramount in guiding the pediatric clinical treatment.


Assuntos
Antibacterianos/farmacologia , Infecções Bacterianas/epidemiologia , Farmacorresistência Bacteriana Múltipla/efeitos dos fármacos , Infecções Bacterianas/microbiologia , Criança , China/epidemiologia , Humanos , Testes de Sensibilidade Microbiana
8.
Anal Bioanal Chem ; 386(7-8): 2035-42, 2006 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-17053916

RESUMO

A simple, sensitive and low-cost method was developed for the determination of aspartate (Asp) and glutamate (Glu) in rabbit retina. Polymer monolith microextraction (PMME) using a poly(acrylamide-vinylpyridine-N,N'-methylene bisacrylamide) (AA-VP-Bis) monolithic column was combined with derivatization of Asp and Glu using 8-phenyl-(4-oxy-acetic acid N-hydroxysuccinimide ester)-4,4-difluoro-1,3,5,7-tetramethyl-4-bora-3a,4a-diaza-s-indacene (TMPAB-OSu), and this was used to analyze the derivatives of Asp and Glu by high-performance liquid chromatography (HPLC) with fluorescence detection. The conditions for the derivatization and the subsequent extraction of Asp and Glu derivatives were optimized. The enrichment factors for the derivatives of Asp and Glu were found to be 14.1 and 14.7, respectively, by PMME. The limits of detection of Asp and Glu were 0.14 and 0.53 nmol/L, respectively. The precision and recovery were evaluated with spiked retina. The inter- and intraday relative standard deviations were less than 10%. The proposed method was successfully applied to the determination of Asp and Glu levels in rabbit retina samples with different stages of intraocular hypertension.


Assuntos
Ácido Aspártico/análise , Ácido Aspártico/isolamento & purificação , Cromatografia Líquida de Alta Pressão/métodos , Ácido Glutâmico/análise , Ácido Glutâmico/isolamento & purificação , Polímeros/química , Retina/química , Animais , Ácido Aspártico/química , Ácido Aspártico/metabolismo , Calibragem , Cromatografia Líquida de Alta Pressão/instrumentação , Fluorescência , Ácido Glutâmico/química , Ácido Glutâmico/metabolismo , Concentração de Íons de Hidrogênio , Hipertensão/metabolismo , Estrutura Molecular , Coelhos , Retina/metabolismo
9.
Anal Chim Acta ; 575(2): 255-61, 2006 Aug 11.
Artigo em Inglês | MEDLINE | ID: mdl-17723599

RESUMO

A precolumn-derivatization high performance liquid chromatographic method for biogenic amine analysis has been developed. Derivatization of biogenic amines was performed with a new fluorescent reagent, 8-phenyl-(4-oxy-acetic acid N-hydroxysuccinimide ester)-4,4-difluoro-1,3,5,7-tetramethyl-4-bora-3a,4a-diaza-s-indacene (TMPAB-OSu), which was synthesized in our lab. The derivatization conditions and the influence of elution composition on the separation were investigated. In pH 8.5 H3BO3-Na2B4O7 media, the reaction of biogenic amines with TMPAB-OSu completed at 45 degrees C for 5 min. The labeled biogenic amines were separated on an ZORBAX Eclipse XDB-C8 column (150 mm x 4.6 mm, 5 microm) and detected with fluorescence at excitation and emission wavelengths of 497 and 509 nm, respectively. Detection limits of biogenic amines were 0.1-4 nmol L(-1), at a signal-to-noise ratio of 3. The proposed method has been applied to the quantitative determination of spermine, phenethylamine, spermidine, cadaverine and putrescine in pericarp and pulp of mature and immature apples and wine with recoveries of 95-102% and R.S.D. of 0.7-3.9.

10.
Talanta ; 69(5): 1190-9, 2006 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-18970702

RESUMO

A novel fluorescent-activated ester, 8-phenyl-(4-oxy-acetic acid N-hydroxysuccinimidyl ester)-4,4-difluoro-1,3,5,7-tetramethyl-4-bora-3a,4a-diaza-s-indacene (TMPAB-OSu) has been designed and synthesized for amine labeling in HPLC. Being used 11 aliphatic amines as the models, the derivatization conditions were optimized. In 0.2 mol/l borate buffer (pH 8.8), amines reacted with TMPAB-OSu at 30 degrees C to form the derivatives in 10 min. The fluorescent quantum yield of TMPAB-OSu and its amine derivatives are high even compared with fluorescein. The separation of these amine derivatives was achieved with a C(8) column and gradient elution by using 0.1 mol/l sodium acetate buffer (pH 5.0) and methanol. With fluorescence detection at an emission wavelength of 509 nm and an excitation wavelength of 497 nm, the detection limits of aliphatic amines were 2-18 fmol, at a signal-to-noise ratio of 3:1. The proposed TMPAB-OSu-based HPLC method has been applied to the analysis of urine samples of health, hepatic and renal patients and lake water. Recoveries from different matrices are from 96 to 104%, depending on the sample investigated.

11.
J Chromatogr A ; 1063(1-2): 143-51, 2005 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-15700466

RESUMO

6-Oxy-(N-succinimidyl acetate)-9-(2'-methoxycarbonyl)fluorescein (SAMF), a new fluorescein-based amine-reactive fluorescent probe was well designed, synthesized and used as a pre-column derivatizing reagent for the determination of aliphatic amines in HPLC. It exhibited relatively pH-independent fluorescence (pH 4-9) and excellent photostability. The derivatization was performed at room temperature in 6min. On a C18 column, the derivatives of SAMF with eight aliphatic amines were baseline separated in 28 min with a mobile phase of methanol-water (57:43, v/v) containing 10 mmol l(-1) pH 5.0, H3Cit3-NaOH buffer. With fluorescent detection at lambda(ex)/lambda(em) = 484/516 nm, the detection limit could reach 2-320 fmol (signal-to-noise = 3), which was equivalent to or better than the detection limits obtained from other analytical methods of aliphatic amines. The proposed method has been applied to the determination of the aliphatic amines in environmental and food samples such as lake water, red wine, white wine, and cheese with satisfying recoveries varying from 95 to 106%.


Assuntos
Aminas/análise , Cromatografia Líquida de Alta Pressão/métodos , Corantes Fluorescentes/química , Succinimidas/química , Aminas/química
12.
Talanta ; 61(6): 797-802, 2003 Dec 23.
Artigo em Inglês | MEDLINE | ID: mdl-18969244

RESUMO

A new synthesized fluorescent probe, 1,3,5,7-tetramethyl-8-(3',4'-diaminophenyl)-difluoroboradiaza-s-indacence (TMDABODIPY), has been used to detect nitrite. When TMDABODIPY reacted with nitrite, a weak fluorescent triazole formed in 0.2 mol l(-1) HCl medium at room temperature. The fluorescence quenching intensity was linear over a nitrite concentration of 0.04-0.32 mumol l(-1) with a detection limit of 0.3 nmol l(-1) (S/N=3). The proposed method has been applied to the determination of total amount of nitrite and nitrate (reduced by Zn powder) in human serum and urine of health and hypertension persons with recoveries of 91.83-101.80%.

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA