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1.
Zhonghua Yu Fang Yi Xue Za Zhi ; 57(11): 1773-1776, 2023 Nov 06.
Artigo em Chinês | MEDLINE | ID: mdl-38008564

RESUMO

Public exposure to radon has attracted increasing public concern. The newly issued "Standards for indoor air quality (GB/T 18883-2022)" has revised the radiological parameters of radon. This study analyzed and discussed the relevant technical contents about the derivation of radon limit, including the distribution level for indoor radon, exposure pathway, health effects, and the process for establishing the standard limits. Specific implementation and evaluation suggestions are also proposed.


Assuntos
Poluição do Ar em Ambientes Fechados , Radônio , Humanos , Radônio/análise , China , Habitação
2.
Zhonghua Yu Fang Yi Xue Za Zhi ; 54(3): 294-300, 2020 Mar 06.
Artigo em Chinês | MEDLINE | ID: mdl-32187935

RESUMO

Objective: To understand the genetic variation and epidemiological characteristics of human respiratory syncytial virus (HRSV) in Guangzhou. Methods: Nasopharyngeal swabs specimens were collected from 0-6 year old children hospitalized with acute respiratory infection, then HRSV was tested and genotyped by RT-PCR. Phylogenetic tree was bulit using MEGA 6.0 software. NetNGlyc 1.0 server was used to predict the potential N-linked glycosylation sites. Results: A total of 1 225 nasopharyngeal specimens were collected, including 783 males and 442 females. The median (P(25), P(75)) age was 8 (3, 24) months. Among the 209 HRSV-positive cases (17.06%), 117 cases (55.98%) were HRSV-A and 92 cases (44.02%) were HRSV-B. The two distinct subgroups (HRSV-A and HRSV-B) alternately played dominant role to cause HRSV infection and exchange almost once every two years. The HRSV prevalence rate decreased with age. The HRSV-positive rate among children under 2 years old was 18.83% (196 cases), accounting for 93.78% of the total positive cases. There were 32 HRSV positive cases co-infected with at least one respiratory virus, with the co-infection rate of 15.31%. Phylogenetic tree analysis of the second hypervariable region (HVR2) of the G protein classified the HRSV-A specimens into ON1 (n=62) and NA1 (n=2) genotypes while all HRSV-B specimens belonged to BA genotype (n=53). The HVR2 of the G protein varied in using stop condon, amino acid substitutions, glycosylation sites. Conclusion: Children under 2 years old were the high risk population of HRSV infection in Guangzhou. ON1 genotype turned into a primary genetype of the HRSV-A subgroup while BA genotype dominated the HRSV-B subgroup. A greater diversification of amino acid substitutions, and some deletion and insertion of glycosylation sites embodied the polymorphism of G protein as main protective antigen.


Assuntos
Infecções por Vírus Respiratório Sincicial/epidemiologia , Vírus Sincicial Respiratório Humano/genética , Vírus Sincicial Respiratório Humano/isolamento & purificação , Criança , Criança Hospitalizada , Pré-Escolar , China/epidemiologia , Feminino , Genótipo , Humanos , Lactente , Recém-Nascido , Masculino , Epidemiologia Molecular , Filogenia , Infecções por Vírus Respiratório Sincicial/diagnóstico
3.
Cryobiology ; 93: 18-26, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32105701

RESUMO

This paper describes the continuation of studies that demonstrated the suitability of CP-Tes solution as a medium for the introduction and removal of dimethyl sulfoxide in rabbit common carotid arteries and established the kinetics of cryoprotectant permeation in that tissue. In this paper we report the tolerance of rabbit common carotid artery to dimethyl sulfoxide, in concentrations up to 30% (w/w), using a technique of exposure that was designed to control osmotic stress. The maximum concentration achieved without damage was 15% (w/w). Vessels were then equilibrated with 15% dimethyl sulfoxide and cooled to -80 °C at 0.22, 0.69, 2.15, or 9.63 °C/min: they were then transferred to the gas phase of a liquid nitrogen refrigerator {temperature below -160 °C) for storage. Thawing was carried out in a 37 °C water bath. The optimum rate of cooling for these conditions was found to be 0.69 °C/min. The maximal recovery of contractile force in response to 10-6 M norepinephrine was 30-40%; relaxation to acetylcholine (an endothelium-mediated function) was 80% of control, and an estimated 71% of endothelial cells survived with minimal ultrastructural change.


Assuntos
Artéria Carótida Primitiva , Criopreservação/métodos , Crioprotetores/farmacologia , Dimetil Sulfóxido/farmacologia , Animais , Sobrevivência Celular/efeitos dos fármacos , Temperatura Baixa , Células Endoteliais/efeitos dos fármacos , Feminino , Masculino , Norepinefrina/farmacologia , Coelhos
4.
Transl Psychiatry ; 8(1): 233, 2018 10 26.
Artigo em Inglês | MEDLINE | ID: mdl-30367029

RESUMO

Impairments in social cognition are believed contribute to disability, particularly for disorders characterized by difficulties in social interaction. There has been little transdiagnostic investigation of this across social cognition domains in young adults. A total of 199 young adults diagnosed with autism spectrum disorder (ASD; N = 53), early psychosis (EP; N = 51), and social anxiety disorder (SAD; N = 64) were compared against neurotypical controls (NT; N = 31) on a battery of lower and higher-order and self-report social cognition measures. For both ASD and EP, participants showed impaired performance on all lower-order emotion recognition tasks and one higher-order social cognition test. Self-reports of empathy were reduced in all clinical groups and particularly in ASD. For SAD, despite showing no objective social cognition impairment, self-reported empathy was reduced to the same level as EP. Discriminant analysis revealed that self-reported empathy and lower-order emotion recognition tests provide best capacity to differentiate groups. Regressions predicting disability revealed depression as the strongest predictor across all disability measures. Empathy provided additional predictive value for social disability and social interaction anxiety. Overall, results support a similar social-cognitive development profile across ASD and EP. While self-reported empathy differentiated between groups, discrepancy between objective social cognition test performance and self-reported empathy in the SAD group suggests probable threat-related self-monitoring report biases that likely further influence all group outcomes. As depression and empathy were the most important predictors of disability, regardless of diagnostic group, research is required to explore targeted interventions for difficulties in these domains to reduce disability.


Assuntos
Transtorno do Espectro Autista/fisiopatologia , Depressão/fisiopatologia , Emoções/fisiologia , Empatia/fisiologia , Fobia Social/fisiopatologia , Transtornos Psicóticos/fisiopatologia , Percepção Social , Adolescente , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Autorrelato , Adulto Jovem
5.
J Environ Biol ; 36(6): 1373-80, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26688976

RESUMO

Waste activated sludge was aerobically treated to demonstrate multiple uses such as cultivating an oil degrading bacterial consortium; studying the influence of a bulking agent (peat moss) and total petroleum hydrocarbon concentration on bacterial growth and producing a soil conditioner using waste activated sludge. After 30 days of incubation, the concentration of oil-degrading bacteria was 4.3 x 10(8) CFU g(-1) and 4.5 x 10(8) CFU g(-1) for 5 and 10 g of total petroleum hydrocarbon, respectively, in a mixture of waste activated sludge (1 kg) and peat moss (0.1 kg). This accounts for approximately 88.4 and 91.1%, respectively, of the total heterotrophic bacteria (total-HB). The addition of bulking agent enhanced total-HB population and total petroleum hydrocarbon-degrading bacterial population. Over 90% of total petroleum hydrocarbon degradation was achieved by the mixture of waste activated sludge, bulking agent and total petroleum hydrocarbon. The results of physico-chemical parameters of the compost (waste activated sludge with and without added peat moss compost) and a substantial reduction in E. coli showed that the use of this final product did not exhibit risk when used as soil conditioner. Finally, the present study demonstrated that cultivation of total petroleum hydrocarbon-degrading bacterial consortium and production of compost from waste activated sludge by aerobic treatment was feasible.


Assuntos
Bactérias/metabolismo , Biodegradação Ambiental , Hidrocarbonetos/metabolismo , Petróleo/metabolismo , Esgotos/microbiologia , Esgotos/química
6.
Braz. j. med. biol. res ; 48(2): 146-153, 02/2015. tab, graf
Artigo em Inglês | LILACS | ID: lil-735854

RESUMO

Although 17β-estradiol (E2) deficiency has been linked to the development of osteoarthritis (OA) in middle-aged women, there are few studies relating other estrogens and estrogen metabolites (EMs) to this condition. We developed a high-performance liquid chromatography-electrospray ionization-tandem mass spectrometry (HPLC-ESI-MS/MS) method to measure the levels of six EMs (i.e., estrone, E2, estriol, 2-hydroxyestrone, 2-hydroxyestradiol, and 16a-hydroxyestrone) in healthy pre- and postmenopausal women and women with OA. This method had a precision ranging from 1.1 to 3.1% and a detection limit ranging from 10 to 15 pg. Compared to healthy women, serum-free E2 was lower in the luteal and postmenopausal phases in women with OA, and total serum E2 was lower in postmenopausal women with OA. Moreover, compared to healthy women, total serum 2-hydroxyestradiol was higher in postmenopausal women with OA and total serum 2-hydroxyestrone was lower in both the luteal and follicular phases in women with OA. In conclusion, our HPLC-ESI-MS/MS method allowed the measurement of multiple biochemical targets in a single assay, and, given its increased cost-effectiveness, simplicity, and speed relative to previous methods, this method is suitable for clinical studies.


Assuntos
Adulto , Idoso , Feminino , Humanos , Pessoa de Meia-Idade , Cromatografia Líquida de Alta Pressão/métodos , Estrogênios/sangue , Osteoartrite/sangue , Pós-Menopausa/sangue , Pré-Menopausa/sangue , Espectrometria de Massas por Ionização por Electrospray/métodos , Estradiol/análogos & derivados , Estradiol/sangue , Estriol/sangue , Estrogênios/metabolismo , Estrona/sangue , Fase Folicular/sangue , Hidroxiestronas/sangue , Limite de Detecção , Fase Luteal/sangue , Osteoartrite/metabolismo , Pós-Menopausa/metabolismo , Pré-Menopausa/metabolismo , Estatísticas não Paramétricas
7.
Braz J Med Biol Res ; 48(2): 146-53, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25410577

RESUMO

Although 17ß-estradiol (E2) deficiency has been linked to the development of osteoarthritis (OA) in middle-aged women, there are few studies relating other estrogens and estrogen metabolites (EMs) to this condition. We developed a high-performance liquid chromatography-electrospray ionization-tandem mass spectrometry (HPLC-ESI-MS/MS) method to measure the levels of six EMs (i.e., estrone, E2, estriol, 2-hydroxyestrone, 2-hydroxyestradiol, and 16a-hydroxyestrone) in healthy pre- and postmenopausal women and women with OA. This method had a precision ranging from 1.1 to 3.1% and a detection limit ranging from 10 to 15 pg. Compared to healthy women, serum-free E2 was lower in the luteal and postmenopausal phases in women with OA, and total serum E2 was lower in postmenopausal women with OA. Moreover, compared to healthy women, total serum 2-hydroxyestradiol was higher in postmenopausal women with OA and total serum 2-hydroxyestrone was lower in both the luteal and follicular phases in women with OA. In conclusion, our HPLC-ESI-MS/MS method allowed the measurement of multiple biochemical targets in a single assay, and, given its increased cost-effectiveness, simplicity, and speed relative to previous methods, this method is suitable for clinical studies.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Estrogênios/sangue , Osteoartrite/sangue , Pós-Menopausa/sangue , Pré-Menopausa/sangue , Espectrometria de Massas por Ionização por Electrospray/métodos , Adulto , Idoso , Estradiol/análogos & derivados , Estradiol/sangue , Estriol/sangue , Estrogênios/metabolismo , Estrona/sangue , Feminino , Fase Folicular/sangue , Humanos , Hidroxiestronas/sangue , Limite de Detecção , Fase Luteal/sangue , Pessoa de Meia-Idade , Osteoartrite/metabolismo , Pós-Menopausa/metabolismo , Pré-Menopausa/metabolismo , Estatísticas não Paramétricas
8.
Cell Death Dis ; 5: e1506, 2014 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-25356875

RESUMO

Long noncoding RNAs (lncRNAs) have important roles in diverse biological processes. Our previous study has revealed that lncRNA-MALAT1 deregulation is implicated in the pathogenesis of diabetes-related microvascular disease, diabetic retinopathy (DR). However, the role of MALAT1 in retinal vasculature remodeling still remains elusive. Here we show that MALAT1 expression is significantly upregulated in the retinas of STZ-induced diabetic rats and db/db mice. MALAT1 knockdown could obviously ameliorate DR in vivo, as shown by pericyte loss, capillary degeneration, microvascular leakage, and retinal inflammation. Moreover, MALAT1 knockdown could regulate retinal endothelial cell proliferation, migration, and tube formation in vitro. The crosstalk between MALAT1 and p38 MAPK signaling pathway is involved in the regulation of endothelial cell function. MALAT1 upregulation represents a critical pathogenic mechanism for diabetes-induced microvascular dysfunction. Inhibition of MALAT1 may serve as a potential target for anti-angiogenic therapy for diabetes-related microvascular complications.


Assuntos
Diabetes Mellitus Experimental/genética , Diabetes Mellitus Experimental/fisiopatologia , Células Endoteliais/patologia , RNA Longo não Codificante/metabolismo , Animais , Movimento Celular , Proliferação de Células , Sobrevivência Celular , Diabetes Mellitus Experimental/patologia , Modelos Animais de Doenças , Células Endoteliais/metabolismo , Técnicas de Silenciamento de Genes , Inflamação , Sistema de Sinalização das MAP Quinases , Camundongos , Neovascularização Fisiológica , Ratos , Vasos Retinianos/patologia , Vasos Retinianos/fisiopatologia , Regulação para Cima/genética , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo
9.
Eur Rev Med Pharmacol Sci ; 18(15): 2116-23, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25070815

RESUMO

OBJECTIVES: To investigate the effect of targeted antiosteosarcoma methotrexate-bisphosphonate conjugate on growth inhibition and apoptosis in human osteosarcoma MG-63 cells. MATERIALS AND METHODS: MG-63 cells were treated with various concentrations of methotrexate-bisphosphonate conjugate and apoptosis was monitored via an MTT assay, cell morphology, TUNEL assay and flow cytometry analysis. RESULTS: The survival rate of MG-63 cells treated for 24 to 96 hours with 2000 mg/ml or more of methotrexate-bisphosphonate conjugate decreased significantly. Cells treated with conjugate showed typical apoptotic features using inverted phase contrast microscopy and fluorescence staining, and the majority of cells demonstrated a positive result in the TUNEL assay. Karyopyknosis and crescent aggregation of chromatin were observed in conjugate-treated cells by electron microscopy. Flow cytometry of MG-63 cells treated with methotrexate-bisphosphonate conjugate showed a time and dose-dependent increase in apoptosis (p < 0.05). CONCLUSIONS: A targeted antiosteosarcoma methotrexate-bisphosphonate conjugate induces apoptosis in human osteosarcoma MG-63 cells. This new conjugate is a valuable experimental tool for the therapy of osteosarcoma.


Assuntos
Apoptose/efeitos dos fármacos , Neoplasias Ósseas/tratamento farmacológico , Difosfonatos/farmacologia , Metotrexato/análogos & derivados , Osteossarcoma/tratamento farmacológico , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Humanos , Metotrexato/farmacologia , Taxa de Sobrevida
10.
Eur J Cancer Care (Engl) ; 23(1): 76-81, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23957529

RESUMO

The aim of the paper is to evaluate the efficacy of CyberKnife® for the treatment of primary or metastatic retroperitoneal tumours. Twenty-eight patients were treated. The prescription isodose line (median, 78%; range, 70-84%) covered the planning target volume at a total dose of 2000-6000 cGy (median, 4500 cGy) and a biologically effective dose of 3750-10,080 cGy (median, 7680 cGy) in 2-10 fractions (median, five fractions). The results showed that the complete response, partial response, stable disease, and progressive disease rates were 43% (12/28), 36% (10/28), 18% (5/28), and 4% (1/28) respectively. The overall response rate was 96%. The 1-, 2- and 3-year local control rates were 92%, 86%, and 86% respectively. The 1-, 2- and 3-year overall survival rates were 60%, 49%, and 49% respectively. No significant difference was found between local progression-free survival and overall survival. Moreover, if a patient only had metastases in the retroperitoneum and local control was effective, there was no significant difference between local progression-free survival and overall progression-free survival. In conclusion, CyberKnife treatment for retroperitoneal tumours resulted in high response rates with minimal side effects. All radiation-induced side effects were well tolerated.


Assuntos
Radiocirurgia , Neoplasias Retroperitoneais/cirurgia , Adulto , Idoso , Idoso de 80 Anos ou mais , Relação Dose-Resposta à Radiação , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Doses de Radiação , Neoplasias Retroperitoneais/patologia , Neoplasias Retroperitoneais/secundário , Análise de Sobrevida , Adulto Jovem
11.
Water Sci Technol ; 67(6): 1324-31, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23508158

RESUMO

Zeolites were synthesized from silica-rich (SF-Z) and calcium-rich (CF-Z) fly ashes, respectively, and their performance in immobilizing ammonium and phosphate was investigated through batch experiments. The cation exchange capacity and phosphate immobilization capacity of SF-Z were identified as 2.79 meq/g and 12.97 mg/g while those of CF-Z were 0.69 meq/g and 87.41 mg/g, respectively. The mixture of SF-Z and CF-Z (MSC-Z) immobilized simultaneously ammonium and phosphate, and the ratio of SF-Z to CF-Z depended on the ammonium and phosphate concentrations in wastewater and the discharge standard. The adsorption processes of ammonium and phosphate on MSC-Z followed Ho's pseudo-second-order model and the intra-particle diffusion was a rate-controlling step. The Langmuir model produced better suitability to the equilibrium data. The thermodynamic study revealed that the adsorption of both ammonium and phosphate on MSC-Z was an endothermic reaction. After treatment by MSC-Z, the ammonium and phosphate concentrations in wastewater from a sewage treatment plant decreased from 7.45 and 1.42 mg/L to 2.06 and 0.51 mg/L, respectively, and met Surface Water Environment Quality Standard in China δ. These results show that the immobilization of ammonium and phosphate in wastewater can be achieved by the combination of zeolites synthesized from silica-rich and calcium-rich fly ashes.


Assuntos
Cinza de Carvão/química , Fosfatos/isolamento & purificação , Compostos de Amônio Quaternário/isolamento & purificação , Poluentes Químicos da Água/isolamento & purificação , Zeolitas/síntese química , Adsorção , Cálcio/química , Concentração de Íons de Hidrogênio , Cinética , Dióxido de Silício/química , Termodinâmica , Águas Residuárias/química
12.
Br J Radiol ; 83(990): 505-8, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20505031

RESUMO

The aim of this study was to investigate the movement, and the factors that influence such movement, of pancreatic lesions and to provide a reference for determination of planning target volume (PTV) during stereotactic radiotherapy. We implanted 19 gold markers into the inner pancreatic tumours of 16 pancreatic carcinoma patients percutaneously under B-ultrasonographic guidance. The marked motion of pancreatic lesions in the x (right-left), y (superoinferior) and z (anteroposterior) directions was measured using an X-ray simulator system. Based on the statistical analysis of the detected movements, we investigated the relevant influencing factors of pancreatic lesions with multinomial linear regression. Data showed that the mean motion amplitudes of pancreatic lesions were 0.16 cm +/- 0.06 (range 0.1-0.3 cm) in the x direction, 0.25 cm +/- 0.12 (range 0.1-0.4 cm) in the y direction and 0.88 cm +/- 0.24 (0.5-1.6 cm) in the z direction. Motion amplitude was not correlated with the height, weight or age of the patients nor with the location or size of the tumour. The motion of pancreatic lesions was mainly influenced by the respiratory motion and has maximal amplitude in the z direction. Therefore, motion in the z direction should be given a priority consideration while determining the PTV.


Assuntos
Movimento , Neoplasias Pancreáticas/diagnóstico por imagem , Planejamento da Radioterapia Assistida por Computador/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Ouro , Humanos , Masculino , Pessoa de Meia-Idade , Próteses e Implantes , Radiografia , Técnicas Estereotáxicas
13.
Braz. j. med. biol. res ; 43(2): 176-185, Feb. 2010. tab, ilus, graf
Artigo em Inglês | LILACS | ID: lil-538231

RESUMO

The molecular mechanisms and potential clinical applications of neural precursor cells have recently been the subject of intensive study. Dlx5, a homeobox transcription factor related to the distal-less gene in Drosophila, was shown to play an important role during forebrain development. The subventricular zone (SVZ) in the adult brain harbors the largest abundance of neural precursors. The anterior SVZ (SVZa) contains the most representative neural precursors in the SVZ. Further research is necessary to elucidate how Dlx5-related genes regulate the differentiation of SVZa neural precursors. Here, we employed immunohistochemistry and molecular biology techniques to study the expression of Dlx5 and related homeobox genes Er81 and Islet1 in neonatal rat brain and in in vitro cultured SVZa neural precursors. Our results show that Dlx5 and Er81 are also highly expressed in the SVZa, rostral migratory stream, and olfactory bulb. Islet1 is only expressed in the striatum. In cultured SVZa neural precursors, Dlx5 mRNA expression gradually decreased with subsequent cell passages and was completely lost by passage four. We also transfected a Dlx5 recombinant plasmid and found that Dlx5 overexpression promoted neuronal differentiation of in vitro cultured SVZa neural precursors. Taken together, our data suggest that Dlx5 plays an important role during neuronal differentiation.


Assuntos
Animais , Ratos , Ventrículos Cerebrais/citologia , Regulação da Expressão Gênica no Desenvolvimento/fisiologia , Proteínas de Homeodomínio/metabolismo , Neurogênese/fisiologia , Neurônios/citologia , Animais Recém-Nascidos , Diferenciação Celular/fisiologia , Ventrículos Cerebrais/metabolismo , Proteínas de Homeodomínio/genética , Imuno-Histoquímica/métodos , Neurônios/fisiologia , Ratos Wistar , Transfecção
14.
Braz J Med Biol Res ; 43(2): 176-85, 2010 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-20027483

RESUMO

The molecular mechanisms and potential clinical applications of neural precursor cells have recently been the subject of intensive study. Dlx5, a homeobox transcription factor related to the distal-less gene in Drosophila, was shown to play an important role during forebrain development. The subventricular zone (SVZ) in the adult brain harbors the largest abundance of neural precursors. The anterior SVZ (SVZa) contains the most representative neural precursors in the SVZ. Further research is necessary to elucidate how Dlx5-related genes regulate the differentiation of SVZa neural precursors. Here, we employed immunohistochemistry and molecular biology techniques to study the expression of Dlx5 and related homeobox genes Er81 and Islet1 in neonatal rat brain and in in vitro cultured SVZa neural precursors. Our results show that Dlx5 and Er81 are also highly expressed in the SVZa, rostral migratory stream, and olfactory bulb. Islet1 is only expressed in the striatum. In cultured SVZa neural precursors, Dlx5 mRNA expression gradually decreased with subsequent cell passages and was completely lost by passage four. We also transfected a Dlx5 recombinant plasmid and found that Dlx5 overexpression promoted neuronal differentiation of in vitro cultured SVZa neural precursors. Taken together, our data suggest that Dlx5 plays an important role during neuronal differentiation.


Assuntos
Ventrículos Cerebrais/citologia , Regulação da Expressão Gênica no Desenvolvimento/fisiologia , Proteínas de Homeodomínio/metabolismo , Neurogênese/fisiologia , Neurônios/citologia , Animais , Animais Recém-Nascidos , Diferenciação Celular/fisiologia , Ventrículos Cerebrais/metabolismo , Proteínas de Homeodomínio/genética , Imuno-Histoquímica/métodos , Neurônios/fisiologia , Ratos , Ratos Wistar , Transfecção
15.
Environ Monit Assess ; 165(1-4): 449-60, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19421882

RESUMO

Heavy metal accumulation (Cu, Zn, Ni, and Pb) in common marine macroalga, Acrosorium uncinatum under nutrient (phosphate and nitrate) enriched (experiment 1) and starved (experiment 2) conditions over a short exposure period (12 h) were examined in this study. Control was maintained in seawater contained nutrient solution without addition of metals and in seawater alone for experiment 1 and 2, respectively. Among the four metals studied, the accumulation of Zn, Ni, and Pb was considerably lower than Cu. The accumulation factor for all metals varies greatly in different nutrient concentrations, but it increases as the exposure of metal concentration decreases in both the experiments. The results of the present findings established that this macroalga is an accumulator of metals Cu, Zn, Ni, and Pb and have the potential to accumulate these metals even in a short time exposure period (12 h). Even though metal accumulation by A. uncinatum largely depends on the available concentration in the medium, nutrients like phosphate and nitrate can affect the accumulation significantly.


Assuntos
Metais Pesados/farmacocinética , Nitratos/química , Fosfatos/química , Rodófitas/metabolismo
16.
Ecotoxicology ; 18(7): 952-60, 2009 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19590954

RESUMO

The heavy metal (Cu, Pb, Ni, and Cd) accumulation capacity of the stem cuttings of the terrestrial, ornamental plant, Talinum triangulare was assessed in hydroponic medium. The stem cuttings of T. triangulare, grew well in distilled water regenerating roots and aerial parts. On exposure to various concentrations of Cu, Pb, Ni, and Cd, a concentration dependent decrease was observed in the number of leaves produced and roots regenerated and an increase in the number of days required for the initiation of roots. The number of leaves produced showed an increasing trend in almost all treatment concentrations of Cu, Pb, Ni, and Cd with an increase in the duration of experiment, whereas, with an increase in the treatment concentration of metals a significant (P < 0.05) decrease was observed in the number of leaves produced. The number of days required for root initiation in metal solutions, however, increased with increasing concentration of Cu, Pb, Ni, and Cd. The root development was completely arrested from 10 mg l(-1) of Ni and 4 mg l(-1) of Cd. Compared to the control, a significant decrease was recorded in the number of roots produced in all treatment concentrations of Cu, Pb, Ni, and Cd. Pink colouration of metal solution consequent to leaching of plant pigment from T. triangulare was observed which was not persistent and disappeared after a few days. Decaying of stem was observed when exposed to Ni and Cd but not to Cu and Pb. Although, copper accumulation by T. triangulare at treatment concentration of 15 and 20 mg l(-1) exceeded 1,000 mg kg(-1) dry matter, necessary pot culture experiment is required before "T. triangulare" can be definitely classified as a Cu hyperaccumulator.


Assuntos
Metais Pesados/toxicidade , Caules de Planta/efeitos dos fármacos , Portulacaceae/efeitos dos fármacos , Poluentes Químicos da Água/toxicidade , Biodegradação Ambiental/efeitos dos fármacos , Hidroponia/métodos , Metais Pesados/metabolismo , Raízes de Plantas/efeitos dos fármacos , Raízes de Plantas/crescimento & desenvolvimento , Raízes de Plantas/metabolismo , Caules de Planta/crescimento & desenvolvimento , Caules de Planta/metabolismo , Portulacaceae/crescimento & desenvolvimento , Portulacaceae/metabolismo , Poluentes Químicos da Água/metabolismo
17.
Osteoarthritis Cartilage ; 16(11): 1379-86, 2008 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-18539055

RESUMO

OBJECTIVE: Long-term storage of articular cartilage (AC) remains challenging due to poor post-thaw viability. An initial step towards addressing this issue is characterizing cryoprotectant (CPA) transport, since ensuring adequate CPA equilibration throughout the tissue offers protection during cooling. This study takes a systematic approach in determining CPA transport rates through bovine AC and uses that information in mathematical models to determine CPA equilibration times. DESIGN: Diffusion of high concentration single (6.9 M dimethyl sulfoxide (DMSO)) and multi-component CPA solutions (VS55, 3.1 M DMSO+2.2 M 1,2-propanediol (PD)+3.1 M formamide (FM)) was measured through AC using (1)H nuclear magnetic resonance (NMR) imaging and localized spectroscopy, respectively. Using experimentally calculated effective diffusivities, diffusion models describing CPA transport through the tissue matrix and across chondrocyte membranes were combined to design a CPA addition and removal scheme for a cartilage plug of clinically relevant dimensions. RESULTS: (1)H NMR imaging and localized spectroscopy experiments suggested that the permeation of CPAs through AC (5 mm diameter, 5-10 mm in thickness) took on the order of 4 h for full equilibration at 22 degrees C. Imaging clearly showed the permeation of DMSO into cartilage over time and localized spectroscopy was able to distinguish the permeation rates of the individual VS55 components and water. Experimentally measured diffusivity values were used in CPA addition/removal simulations with a cartilage plug of clinically relevant dimensions (5 mm diameter, 2 mm in thickness). Results suggested a multi-step approach for adding and removing high concentration CPAs, with the addition and removal each taking approximately 2 h to complete. CONCLUSIONS: This study provides a foundation for designing CPA addition and removal protocols for effective long-term storage of cartilage tissue using a novel approach to measure CPA permeation.


Assuntos
Cartilagem Articular/metabolismo , Permeabilidade da Membrana Celular/efeitos dos fármacos , Criopreservação/métodos , Crioprotetores/farmacologia , Dimetil Sulfóxido/farmacologia , Animais , Cartilagem Articular/química , Bovinos , Crioprotetores/análise , Dimetil Sulfóxido/análise , Espectroscopia de Ressonância Magnética/métodos , Modelos Biológicos , Permeabilidade , Fatores de Tempo
18.
J Nat Prod ; 70(1): 114-7, 2007 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-17253861

RESUMO

Two new benzo[j]fluoranthene-based secondary metabolites named daldinone C (1) and daldinone D (2), along with two known metabolites, altechromone A and (4S)-5,8-dihydroxy-4-methoxy-alpha-tetralone, were isolated from the CHCl3/MeOH (1:1) extract of a solid culture of the endophyte Hypoxylon truncatum IFB-18 harbored inside the symptomless stem tissue of Artemisia annua. The structures of the new compounds were elucidated by MS and 1D and 2D NMR spectra and by X-ray diffraction analysis. Their absolute configurations were determined unambiguously by a combination of their CD data and the established exciton chirality rule. Compounds 1 and 2 were substantially cytotoxic against SW1116 cells, with IC50 values of 49.5 and 41.0 microM, respectively, comparable to that (37.0 microM) of 5-fluorouracil. The biosynthetic pathway for 1 and 2 was postulated with the natural occurrence of benzo[j]fluoranthene analogues discussed in brief.


Assuntos
Antineoplásicos , Ascomicetos/química , Fluorenos , Antineoplásicos/química , Antineoplásicos/isolamento & purificação , Antineoplásicos/farmacologia , Artemisia annua , China , Cristalografia por Raios X , Ensaios de Seleção de Medicamentos Antitumorais , Fluorenos/química , Fluorenos/isolamento & purificação , Fluorenos/farmacologia , Humanos , Concentração Inibidora 50 , Conformação Molecular , Estrutura Molecular , Plantas Medicinais
19.
Biotech Histochem ; 81(1): 13-21, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-16760123

RESUMO

Mitotic chromosome spreads of 16 plant species belonging to six families were analyzed using an improved combined PI and DAPI (CPD) staining procedure. Fluorescence in situ hybridization (FISH) with 45S rDNA probe was conducted sequentially on the same spreads to evaluate the efficiency and sensitivity of the technique. Fluorochrome staining with chromomycin A3 (CMA)-DAPI also was conducted to clarify the properties of the sequences involved in the CPD banded regions. Our results revealed that all of the NORs (rDNA sites) in the species tested were efficiently shown as red bands by CPD staining, and the number and position of the bands corresponded precisely to those of the 45S rDNA FISH signals, indicating that the detection sensitivity of CPD staining is similar to that of FISH. In 10 of the species tested including Aegilops squarrosa, Allium sativum, Oryza sativum ssp. indica, Oryza officinalis, Pisum sativum, Secale cereale, Setaria italica, Sorghum vulgare, Vicia faba and Zea mays, CPD bands were exhibited exclusively in their NORs, while in other six species including Hordeum vulgare, Allium cepa, Psophocarpus tetragonolobus, Arabidopsis thaliana, Brassica oleracea var. capitata and Lycopersicon esculentum, CPD bands appeared in chromosomal regions other than their NORs. The CPD bands were in accordance with the CMA bands in all species tested, indicating GC-rich sequences in the CPD bands and that the improved CPD staining procedure is specific for GC-rich regions in plant genomes. Our investigation not only elucidated the banding mechanisms of CPD, but also demonstrated that the CPD staining technique, which may be preferable to CMA staining, is an effective tool for detecting NORs and other GC-rich chromosomal regions in plants.


Assuntos
Bandeamento Cromossômico/métodos , Cromossomos/química , Corantes Fluorescentes , Sequência Rica em GC , Indóis , Região Organizadora do Nucléolo/química , Cromossomos/ultraestrutura , Região Organizadora do Nucléolo/ultraestrutura , Plantas/genética , Plantas/ultraestrutura , Sensibilidade e Especificidade , Coloração e Rotulagem
20.
Planta Med ; 71(11): 1063-5, 2005 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-16320210

RESUMO

In addition to 7-methoxy-2-methyl-3,4,5-trihydroxyanthraquinone (1), physcion (2), macrosporin (3), deoxybostrycin (4), altersolanol B (5) and dactylariol (6), a new hexahydroanthraquinone named pleospdione (7) was isolated from the culture of Pleospora sp . IFB-E006, an endophytic fungus residing in the normal stem of Imperata cylindrical (Gramineae). Structure determination of pleospdione was accomplished using IR, HR-ESI-MS, 1D and 2D NMR spectral analysis. Compounds 4 - 6 exhibited significant cytotoxic activity against human colon cancer (SW1116) and leukemia (K562) cell lines while compounds 1, 2 and 7 were only weakly or moderately active.


Assuntos
Antraquinonas/química , Antraquinonas/farmacologia , Antineoplásicos/química , Antineoplásicos/farmacologia , Ascomicetos/química , Poaceae/microbiologia , Antraquinonas/isolamento & purificação , Antineoplásicos/isolamento & purificação , Humanos , Células K562 , Estrutura Molecular , Ressonância Magnética Nuclear Biomolecular
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