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1.
J Appl Toxicol ; 2024 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-38782376

RESUMO

Legubicin is a novel conjugate of doxorubicin and a legumain-cleavable peptide linker. It has been developed to ameliorate the side effects of doxorubicin. Biodistribution in tumor-bearing mice, acute tolerance, and potential systemic toxic effects in Sprague-Dawley rats and beagle dogs of legubicin were assessed. Legubicin exists mainly as a protein complex in plasma after entering the circulation. Compared with conventional doxorubicin at an equal molar dose in mice, we found higher exposure to doxorubicin in tumor (approximately 1.7-fold increase) while lower exposure in normal tissues (an ~3.26-, 3.46-, and 1.29-fold reduction in heart, kidney, and plasma, respectively) in tumor-bearing mice after intravenous injection of legubicin. The acute maximum tolerance dose (MTD) of legubicin was >16 mg/kg doxorubicin equivalent in female rats, 11 mg/kg doxorubicin equivalent in male rats (LD50 of conventional doxorubicin is 10.51 mg/kg), and >8 mg/kg doxorubicin equivalent in dogs (MTD of conventional doxorubicin is 1.5 mg/kg). Four-week repeat-dose toxicity studies of intravenous legubicin were conducted in rats (5, 10, and 25 mg/kg/dose once weekly) and dogs (3/1.5, 10/5, and 20/10 mg/kg/dose once weekly); the dose levels were reduced from the second dose due to intolerable legubicin-associated toxicity at 20 mg/kg. Major organs of toxicity included the gastrointestinal tract, lymphoid and hematopoietic organs, kidney, skin, liver, reproductive organs, and peripheral nerves, which are all associated with doxorubicin. However, cardiotoxicity was only noted at MTD dose levels. Altogether, our results confirm an improved safety profile of legubicin over conventional doxorubicin and support its clinical benefit for treating cancer.

2.
Eur J Drug Metab Pharmacokinet ; 49(3): 317-330, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38393637

RESUMO

BACKGROUND AND OBJECTIVE: HY-088 injection is an ultrasmall superparamagnetic iron oxide nanoparticle (USPIOs) composed of iron oxide crystals coated with polyacrylic acid (PAA) on the surface. The purpose of this study was to investigate the pharmacokinetics, tissue distribution, and mass balance of HY-088 injection. METHODS: The pharmacokinetics of [55Fe]-HY-088 and [14C]-HY-088 were investigated in 48 SD rats by intravenous injection of 8.5 (low-dose group), 25.5 (medium-dose group), and 85 (high-dose group) mg/100 µCi/kg. Tissue distribution was studied by intravenous injection of 35 mg/100 µCi/kg in 48 SD rats, and its tissue distribution in vivo was obtained by ex vivo tissue assay. At the same time, [14C]-HY-088 was injected intravenously at a dose of 25.5 mg/100 µCi/kg into 16 SD rats, and its tissue distribution in vivo was studied by quantitative whole-body autoradiography. [14C]-HY-088 and [55Fe]-HY-088 were injected intravenously into 24 SD rats at a dose of 35 mg/100 µCi/kg, and their metabolism was observed. RESULTS: In the pharmacokinetic study, [55Fe]-HY-088 reached the maximum observed concentration (Cmax) at 0.08 h in the low- and medium-dose groups of SD rats. [14C]-HY-088 reached Cmax at 0.08 h in the three groups of SD rats. The area under the concentration-time curve (AUC) of [55Fe]-HY-088 and [14C]-HY-088 increased with increasing dose. In the tissue distribution study, [55Fe]-HY-088 and [14C]-HY-088 were primarily distributed in the liver, spleen, and lymph nodes of both female and male rats. In the mass balance study conducted over 57 days, the radioactive content of 55Fe from [55Fe]-HY-088 was primarily found in the carcass, accounting for 86.42 ± 4.18% in females and 95.46 ± 6.42% in males. The radioactive recovery rates of [14C]-HY-088 in the urine of female and male rats were 52.99 ± 5.48% and 60.66 ± 2.23%, respectively. CONCLUSIONS: Following single intravenous administration of [55Fe]-HY-088 and [14C]-HY-088 in SD rats, rapid absorption was observed. Both [55Fe]-HY-088 and [14C]-HY-088 were primarily distributed in the liver, spleen, and lymph nodes. During metabolism, the radioactivity of [55Fe]-HY-088 is mainly present in the carcass, whereas the 14C-labeled [14C]-HY-088 shell PAA is eliminated from the body mainly through the urine.


Assuntos
Nanopartículas Magnéticas de Óxido de Ferro , Ratos Sprague-Dawley , Animais , Distribuição Tecidual , Masculino , Ratos , Feminino , Nanopartículas Magnéticas de Óxido de Ferro/química , Injeções Intravenosas , Nanopartículas de Magnetita/química , Dextranos/farmacocinética , Resinas Acrílicas/química , Resinas Acrílicas/farmacocinética
3.
Molecules ; 27(23)2022 Dec 02.
Artigo em Inglês | MEDLINE | ID: mdl-36500589

RESUMO

Arsenic is a toxic non-metallic element that is widely found in nature. In addition, arsenic and arsenic compounds are included in the list of Group I carcinogens and toxic water pollutants. Therefore, rapid and efficient methods for detecting arsenic are necessary. In the past decade, a variety of small molecule fluorescent probes have been developed, which has been widely recognized for their rapidness, efficiency, convenience and sensitivity. With the development of new nanomaterials (AuNPs, CDs and QDs), organic molecules and biomolecules, the conventional detection of arsenic species based on fluorescence spectroscopy is gradually transforming from the laboratory to the portable kit. Therefore, in view of the current research status, this review introduces the research progress of both traditional and newly developed fluorescence spectrometry based on novel materials for arsenic detection, and discusses the potential of this technology in the rapid screening and field testing of water samples contaminated with arsenic. The review also discusses the problems that still exist in this field, as well as the expectations.


Assuntos
Arsênio , Nanopartículas Metálicas , Poluentes da Água , Arsênio/análise , Corantes Fluorescentes , Ouro/análise , Poluentes da Água/análise
4.
Nucl Med Commun ; 43(7): 834-846, 2022 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-35438673

RESUMO

PURPOSE: To develop a method for labeling human bone marrow mesenchymal stem cells (hMSCs) with 89Zr-oxine to characterize the biodistribution characteristics of hMSCs in normal Sprague-Dawley (SD) rats in real-time by micro-PET-computed tomography (micro-PET/CT) imaging. METHODS: 89Zr-oxine complex was synthesized from 89Zr-oxalate and 8-hydroxyquinoline (oxine). After hMSCs were labeled with the 89Zr-oxine complex, the radioactivity retention, viability, proliferation, apoptosis, differentiation, morphology, and phenotype of labeled cells were assessed. The biodistribution of 89Zr-oxine-labeled hMSCs in SD rats was tracked in real-time by micro-PET/CT imaging. RESULTS: The cell labeling efficiency was 52.6 ± 0.01%, and 89Zr-oxine was stably retained in cells (66.7 ± 0.9% retention on 7 days after labeling). Compared with the unlabeled hMSCs, 89Zr-oxine labeling did not affect the biological characteristics of cells. Following intravenous administration in SD rats, labeled hMSCs mainly accumulated in the liver (7.35 ± 1.41% ID/g 10 days after labeling, n = 6) and spleen (8.48 ± 1.20% ID/g 10 days after labeling, n = 6), whereas intravenously injected 89Zr-oxalate mainly accumulated in the bone (4.47 ± 0.35% ID/g 10 days after labeling, n = 3). CONCLUSION: 89Zr-oxine labeling and micro-PET/CT imaging provide a useful and non-invasive method of assessing the biodistribution of cell therapy products in SD rats. The platform provides a foundation for us to further understand the mechanism of action and migration dynamics of cell therapy products.


Assuntos
Células-Tronco Mesenquimais , Oxiquinolina , Animais , Medula Óssea , Humanos , Oxalatos , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Radioisótopos , Ratos , Ratos Sprague-Dawley , Distribuição Tecidual , Tomografia Computadorizada por Raios X , Zircônio/farmacologia
5.
Talanta ; 238(Pt 1): 123026, 2022 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-34857345

RESUMO

Herein we designed a highly sensitive and selective biosensor for methamphetamine (METH) detection based on aptamer recognition probe and atom transfer radical polymerization (ATRP) signal amplification strategy. In this experiment, METH aptamer and its complementary DNA strand were first attached to the electrode surface. In the presence of METH, the prioritized conjugation between METH and the aptamer will take one strand of DNA from the double-stranded DNA, so that the third segment of azide-modified DNA could be successfully modified onto the electrode surface. Through click chemistry and ATRP polymerization, the monomers with ferrocene were polymerized into a long chain, and the signal was amplified, then high-sensitivity detection of METH can be carried out. The result showed that the sensor could detect METH as low as 17 fM, which is about two orders of magnitude lower than that by traditional METH detection methods. Moreover, when different concentrations of METH were added to serum and urine, the recovery rate of the biosensor was as high as 93%. Therefore, using nucleic acid aptamer as capture probe and ATRP as signal amplification strategy can provide a promising application platform for sensitive detection of low concentration toxicants.


Assuntos
Técnicas Biossensoriais , Metanfetamina , Técnicas Eletroquímicas , Limite de Detecção , Polimerização
6.
Anal Chim Acta ; 1184: 339041, 2021 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-34625250

RESUMO

Cocaine (Coc) is one of the illegal drugs and is harmful to digestive, immune, cardiovascular and urogenital systems. To achieve drug abuse control and legal action, it is essential to develop an effective method for cocaine analysis. In this work, an aptasensor has been developed using atom transfer radical polymerization (ATRP) based on host-guest chemistry for electrochemical analysis of cocaine. The NH2-DNA (Apt1) was immobilized on the indium tin oxide (ITO) electrode via addition reaction, and Fc-DNA (Apt2) was introduced to ITO relying on the specific recognition of cocaine. The Apt2 can initiate host-guest chemistry between Apt2 and ATRP initiators (ß-CD-Br15), then the ß-CD-Br15 further triggers ATRP. Moreover, ATRP avoids the sluggish kinetics and poor coupling capability sustained. The result shows a sensitive and selective analysis of cocaine within a linear range from 0.1 ng/mL to 10 µg/mL (R2 = 0.9985), with the detection limit down to 0.0335 ng/mL. Thus, this strategy provides a universal method for the analysis of illegal drugs.


Assuntos
Técnicas Biossensoriais , Cocaína , Técnicas Eletroquímicas , Eletrodos , Polimerização
7.
Pharmacol Res Perspect ; 8(6): e00696, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-33300686

RESUMO

Anti-tuberculosis drug-induced hepatotoxicity (ATDH) is a serious adverse drug reaction. Conflicting results have been obtained regarding the associations of nuclear receptor subfamily 1 group I member 2 (NR1I2) gene polymorphisms on susceptibility to ATDH. Therefore, we aimed to evaluate the associations using a systematic review/meta-analysis approach. PubMed, Medline, Cochrane Library, Web of Science and SinoMed databases were searched for all eligible studies from inception to June 10, 2020. Pooled adjusted odds ratios (ORs) with 95% confidence intervals (CIs) were employed to evaluate the strength of the association between the NR1I2 polymorphisms and the risk of ATDH. Subgroup analysis was performed by region of origin, and meta-regression were performed to detect potential sources of heterogeneity. A total of five case-control studies involving 572 cases and 1867 controls were identified. Fourteen SNPs in the NR1I2 gene have been reported, and the most heavily studied SNPs were rs3814055 and rs7643645. The pooled estimates did not exhibit any significant associations between SNPs rs3814055 and rs7643645 and the risk of ATDH (rs3814055: dominant model, OR = 1.00, 95% CI: 0.82-1.22, P = 1.00; recessive model, OR = 1.17, 95% CI: 0.76-1.78, P = .48; rs7643645: dominant model, OR = 1.04, 95% CI: 0.64-1.68, P = .89; recessive model, OR = 0.98, 95% CI: 0.65-1.49, P = .93). Subgroup analysis obtained similar negative results in Chinese patients, and the diagnostic criteria of ATDH may be the source of heterogeneity. Based on the meta-analysis described in this report, we did not observe any association between NR1I2 gene polymorphisms and ATDH susceptibility. However, this conclusion should be interpreted with caution due to the low number of studies and the relatively small sample size.


Assuntos
Antituberculosos/efeitos adversos , Doença Hepática Induzida por Substâncias e Drogas/genética , Polimorfismo de Nucleotídeo Único/genética , Receptor de Pregnano X/genética , Animais , Estudos de Casos e Controles , Doença Hepática Induzida por Substâncias e Drogas/diagnóstico , Doença Hepática Induzida por Substâncias e Drogas/epidemiologia , Humanos , Fatores de Risco
8.
Toxicol Res (Camb) ; 9(4): 390-398, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32905219

RESUMO

Cinobufotalin injection, a traditional Chinese medicine preparation, successfully used for several years, might induce cardiotoxicity. The aim of the study was to evaluate the cardiotoxicity of cinobufotalin injection and the cardiotoxicity-preventive effect of sodium phenytoin in vivo. According to the 4 × 4 Latin square design, four Beagle dogs were allocated into four dose levels of 0, 0.3, 1, and 3 g/kg in treatment phases I-IV (cinobufotalin injection) and 3 g/kg in treatment phase V (cardiotoxicity antidote). The following parameters and endpoints were assessed: clinical observations, body weight, indicators of myocardial injury, and electrocardiogram (ECG) parameters. The cinobufotalin injection-related changes were observed in clinical observations (rapid breathing pattern), indicators of myocardial injury (increased cardiac troponin I, creatine kinase isoenzymes, and aspartate aminotransferase), and ECG graphics (arrhythmia) at 3 g/kg concentration in treatment phases I-IV. The cardiotoxicity of cinobufotalin injection was attenuated by sodium phenytoin in treatment phase V. The results confirmed the cardiotoxicity of cinobufotalin injection, and they might bring information about the appropriate monitoring time points and cardiotoxicity parameters in clinical practices and shed light on the treatment of cardiovascular adverse reactions.

9.
Chem Commun (Camb) ; 56(49): 6636-6639, 2020 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-32406442

RESUMO

In this paper, an ultrasensitive, highly selective and green electrochemical biosensor for quantifying DNA sequences (aM DNA) based on a MnTBAP catalyst for AGET ATRP reaction is proposed. For the first time, a combination of biomimetic catalyzed free radical polymerization and DNA electrochemical biosensing was used as a signal amplification strategy.


Assuntos
Materiais Biomiméticos/química , Técnicas Biossensoriais , DNA/análise , Técnicas Eletroquímicas , Compostos Organometálicos/química , Catálise , Elétrons , Radicais Livres/química , Polimerização
10.
Biosens Bioelectron ; 131: 193-199, 2019 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-30836271

RESUMO

Here we report a highly selective and ultrasensitive DNA biosensor based on electrochemical atom transfer radical polymerization (ATRP) signal amplification and "Click Chemistry". The DNA biosensor was prepared by immobilizing thiol and azide modified hairpin DNAs on gold electrode surface. In the presence of target DNAs (T-DNA), hairpin probes hybridized with T-DNAs to form a duplex DNA, and the ring of hairpin DNA was opened to make azide groups accessible at 3' ends. "Click reactions" proceeded between the azide and propargyl-2-bromoisobutyrate (PBIB) to initiate the ATRP reaction which brought a large number of ferrocenylmethyl methacrylate (FMMA) on the electrode surface. The amount of FMMA was proportional to the concentration of T-DNA and quantified by square wave voltammetry. Combining ATRP signal amplification with "Click Chemistry", the optimized DNA biosensor was capable of detecting 0.2 aM. T-DNA. The preliminary application of the developed DNA biosensor was demonstrated by detecting target DNA in spiked serum samples. The developed DNA biosensor shows great promise for the detection of gene biomarkers.


Assuntos
Técnicas Biossensoriais , DNA Bacteriano/química , DNA/isolamento & purificação , Técnicas Eletroquímicas , Azidas/química , DNA/química , Ouro/química , Limite de Detecção , Polimerização
11.
J Appl Toxicol ; 39(7): 945-954, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-30834569

RESUMO

Fluorinated diiodine alkanes (FDIAs), important industrial intermediates in the synthesis of various perfluorinated compounds, which are distributed widely in wildlife and humans. Recent studies showed that FDIAs had in vitro estrogenic effects. However, to date, little information is available regarding the in vivo estrogenic effects of FDIAs and the mechanisms are unclear. In this study, a combination of in vitro and in vivo assays was used to investigate the estrogenic effects of FDIAs. We tested the in vitro estrogenic effects and estrogen receptor-related gene expression via MCF-7 cell assay. The hormone level of estradiol and the expression of estrogenic synthesis genes were measured in the H295R cell assay. Finally, the in vivo effects of FDIAs on development and estrogen-related gene expression were assessed in the zebrafish embryos assay. The results demonstrated that FDIAs could exhibit estrogenic activity through inducing cell proliferation (1.6-6.7-fold of the control) and estrogen receptor alpha gene expression (1.07-1.39-fold of the control), altering estradiol production (1.14-1.22-fold of the control) and the major estrogenic synthesis gene expression of CYP19 (1.22-1.31-fold of the control), disrupting the estrogen-related genes (esr1 and cyp19b) levels in zebrafish (1.52-2.99-fold and 2.95-5.00-fold of the control for esr1 and cyp19b, respectively). The current findings indicated the potential estrogenic effects of FDIAs and provided novel information for human risk assessment.


Assuntos
Embrião não Mamífero/efeitos dos fármacos , Estradiol/metabolismo , Estrogênios/toxicidade , Hidrocarbonetos Fluorados/toxicidade , Hidrocarbonetos Iodados/toxicidade , Peixe-Zebra , Alcanos/toxicidade , Animais , Linhagem Celular , Proliferação de Células/efeitos dos fármacos , Embrião não Mamífero/metabolismo , Estradiol/biossíntese , Receptor alfa de Estrogênio/genética , Expressão Gênica/efeitos dos fármacos , Humanos , Células MCF-7
12.
Contrast Media Mol Imaging ; 2018: 5237950, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29681781

RESUMO

This study aimed to explore the use of 131I-Hoechst 33258 (131I-H33258) for early prediction of tumor response to vascular-disrupting agents (VDAs) with combretastatin-A4 phosphate (CA4P) as a representative. Necrosis avidity of 131I-H33258 was evaluated in mouse models with muscle necrosis and blocking was used to confirm the tracer specificity. Therapy response was evaluated by 131I-H33258 SPECT/CT imaging 24 h after CA4P therapy in W256 tumor-bearing rats. Radiotracer uptake in tumors was validated ex vivo using γ-counting, autoradiography, and histopathological staining. Results showed that 131I-H33258 had predominant necrosis avidity and could specifically bind to necrotic tissue. SPECT/CT imaging demonstrated that an obvious "hot spot" could be observed in the CA4P-treated tumor. Ex vivo γ-counting revealed 131I-H33258 uptake in tumors was increased 2.8-fold in rats treated with CA4P relative to rats treated with vehicle. Autoradiography and corresponding H&E staining suggested that 131I-H33258 was mainly localized in necrotic tumor area and the higher overall uptake in the treated tumors was attributed to the increased necrosis. These results suggest that 131I-H33258 can be used to image induction of cell necrosis 24 h after CA4P therapy, which support further molecular design of probes based on scaffold H33258 for monitoring of tumor response to VDAs treatment.


Assuntos
Bisbenzimidazol/farmacocinética , Necrose/diagnóstico por imagem , Tomografia Computadorizada com Tomografia Computadorizada de Emissão de Fóton Único/métodos , Estilbenos/uso terapêutico , Animais , Antineoplásicos Fitogênicos , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , Radioisótopos do Iodo , Camundongos , Músculo Esquelético/patologia , Ratos , Estilbenos/farmacologia
13.
Tumour Biol ; 35(10): 10409-18, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25053599

RESUMO

This study aims to evaluate the risk and benefit profiles of panitumumab-based therapy (PBT) in patients with metastatic colorectal cancer (mCRC). Relevant randomized controlled trials were identified by searching PubMed, Medline, EMBASE and Cochrane Library. Data on progression-free survival (PFS), overall survival (OS), all grade and severe (grade ≥3) adverse events were extracted and pooled to calculate hazard ratios (HRs) and risk ratios (RRs) with 95 % confidence intervals (CIs). Number needed to treat (NNT) for PFS and number needed to harm (NNH) for significantly changed toxicities were calculated. A total of 4,155 patients were included in the analysis. PBT significantly improved PFS (HRrandom = 0.66, 95 % CI = 0.45-0.95) but not OS (HRfixed = 0.93, 95 % CI = 0.83-1.04) when used in the subsequent-line setting. The effect on PFS was more evident in patients with wild-type KRAS (HRrandom = 0.64, 95 % CI = 0.47-0.87) and the NNT for PFS is 11 to 23at 1 year. PBT did not benefit patients when used in the first-line setting. In addition, PBT significantly increased the risk of skin toxicity, infections, diarrhea, dehydration, mucositis, hypokalemia, fatigue, hypomagnesemia, pulmonary embolism and paronychia. The NNHs for skin toxicity, diarrhea, infection, hypokalemia and mucositis are less than 23. In conclusion, when used in the subsequent-line setting, PBT can improve the disease progression, especially in mCRC patients with wild-type KRAS. Regarding the adverse events associated with the PBT, close monitoring and necessary preparations are recommended during the therapy.


Assuntos
Anticorpos Monoclonais/uso terapêutico , Antineoplásicos/uso terapêutico , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/mortalidade , Humanos , Panitumumabe , Ensaios Clínicos Controlados Aleatórios como Assunto , Medição de Risco
14.
Toxicol Mech Methods ; 24(2): 142-50, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24274596

RESUMO

There have been many studies investigating the genomic biomarker and/or molecular mechanism of nephrotoxicity using microarray. However, most of these researches were carried out by studying gene expression changes at one specific time point. As gene expression varies with time and disease stage, the current study investigated the time-series pattern of gene expression in a rat model using a typical nephrotoxic compound. Rats were administrated with 80 mg/kg gentamycin or saline by intramuscular injection for 14 consecutive days followed by a 28-d recovery. Rats were scarified on D2, D4, D8, D15 and Recovery Day (R29), when kidneys were obtained for whole-genome microarray analysis and histological examination. Urine was collected at each necropsy for kidney injury molecular-1 (KIM-1) analysis. The KIM-1 detection and histological examination confirmed the nephrotoxicity. After differentially expression genes (DEGs) identification, there were 4360 and 4323 regulated genes for females and males, respectively. However, few overlapping expression genes co-regluated at each time point were found. By principle component analysis (PCA) and hierarchical cluster, the gene expression patterns were observed to be apparently associated with the disease stage. GO Annotation showed (1) immune response and related process, response to wounding, cell locomotion on D2; (2) cell death and apoptosis was also noted on D4; (3) processes of organic acid or carboxylic acid, apoptosis or cell death on D8 and D15; (4) processes of cell cycle, mitosis, division cell cycle on R29. In conclusion, the authors mapped the time-series gene expression patterns at the initiation, development and recovery stage of gentamycin-induced nephrotoxicity.


Assuntos
Antibacterianos/toxicidade , Perfilação da Expressão Gênica , Gentamicinas/toxicidade , Rim/efeitos dos fármacos , Animais , Sequência de Bases , Moléculas de Adesão Celular/genética , Primers do DNA , Ensaio de Imunoadsorção Enzimática , Feminino , Rim/metabolismo , Masculino , Análise de Componente Principal , Ratos , Ratos Sprague-Dawley , Reação em Cadeia da Polimerase em Tempo Real
15.
Sheng Li Ke Xue Jin Zhan ; 45(5): 385-90, 2014 Oct.
Artigo em Chinês | MEDLINE | ID: mdl-25764800

RESUMO

The dysfunction of vascular system is one of the main causes of orthostatic intolerance induced by microgravity. Vascular endothelial cell is a single layer on the inner wall of the blood vessel and is the important component of the blood vessel wall. Vascular endothelial cell plays a pivotal role in the regulation of vascular functions, such as serving as a permeability barrier, regulating vasoconstriction and vasodilatation. Recent studies have demonstrated that microgravity may have different effects on vascular sys- tem and vascular endothelial cells in different parts of the body, such as increasing vasoconstrictor reactivity and decreasing vasodilator reactivity of cerebral arteries, decreasing vasoconstrictor and vasodilator reactivity of carotid and abdominal aortic arteries, decreasing vasoconstrictor reactivity and increasing vasodilator reactivity of pulmonary arteries, decreasing vasoconstrictor reactivity of mesenteric arteries and veins and lower extremity arteries. In addition, microgravity can promote the growth of vascular endothelial cells in the large vessels and inhibit the growth of microvascular endothelial cells. This paper summarized the research progress in the effects of microgravity on blood vessels and vascular endothelial cells.


Assuntos
Células Endoteliais , Ausência de Peso , Artérias Mesentéricas , Artéria Pulmonar , Vasoconstrição , Vasoconstritores , Vasodilatação , Vasodilatadores
16.
Fa Yi Xue Za Zhi ; 29(6): 454-7, 2013 Dec.
Artigo em Chinês | MEDLINE | ID: mdl-24665620

RESUMO

As an important component of judicial expertise, forensic science is broad and highly specialized. With development of network technology, increasement of information resources, and improvement of people's legal consciousness, forensic scientists encounter many new problems, and have been required to meet higher evidentiary standards in litigation. In view of this, evidence-based concept should be established in forensic medicine. We should find the most suitable method in forensic science field and other related area to solve specific problems in the evidence-based mode. Evidence-based practice can solve the problems in legal medical field, and it will play a great role in promoting the progress and development of forensic science. This article reviews the basic theory of evidence-based medicine and its effect, way, method, and evaluation in the forensic medicine in order to discuss the application value of forensic evidence-based medicine in computer communication networks.


Assuntos
Redes de Comunicação de Computadores , Medicina Baseada em Evidências , Medicina Legal , Ciências Forenses , Humanos
17.
Sichuan Da Xue Xue Bao Yi Xue Ban ; 41(1): 73-6, 2010 Jan.
Artigo em Chinês | MEDLINE | ID: mdl-20369474

RESUMO

OBJECTIVE: To study the impact of N' N-methylene-bis on thyroglobulin produced by FRTL-5 cells, and to explore the potential of using FRTL-5 cells to screen environmental thyroid hormone disruptors in vitro. METHODS: The FRTL-5 cells were treated with 0.1, 1.0 and 10.0 microg/mL N'N-methylene-bis for 48 hours, respectively. The concentrations of thyroglobulin in the medium of the treated cells were detected by radioimmunoassay. The expression of thyroid peroxidases in the FRTL-5 cells was assessed by enzyme cytochemistry technique. The ultrastructure of the cells was also observed. RESULTS: The FRTL-5 cells treated with 0.1 and 1.0 microg/mL of N' N-methylene-bis produced less thyroglobulin than the controls (P < 0.05). No thyroglobulin was detected with the cells treated with 10.0 microg/mL of N' N-methylene-bis. No difference in the expression of thyroid peroxidases was found between the treated cells and the controls. The treated cells had expanded rough endoplasmic reticulum. CONCLUSION: N' N-methylene-bis disrupts the bio-function of thyroid by damaging the rough endoplasmic reticulum of thyroid follicular cells. FRTL-5 cells can be used for screening thyroid hormone disruptors in vitro.


Assuntos
Disruptores Endócrinos/toxicidade , Praguicidas/toxicidade , Tiadiazóis/toxicidade , Tireoglobulina/análise , Glândula Tireoide/efeitos dos fármacos , Animais , Linhagem Celular , Retículo Endoplasmático Rugoso/efeitos dos fármacos , Iodeto Peroxidase/análise , Ratos , Glândula Tireoide/citologia
18.
Wei Sheng Yan Jiu ; 39(1): 83-5, 2010 Jan.
Artigo em Chinês | MEDLINE | ID: mdl-20364597

RESUMO

OBJECTIVE: To study the effect of perinatal exposure sulphamethazine on the function of thyroid gland of SD rats. METHODS: Dams were given sulphamethazine 0, 50, 100 and 200 mg/(kg x d) respectively from gestational day (GD) 7 to postpartum day (P) 21. The sections of thyroid gland of pups 20 days after birth were stained by hematoxylin-eosin, and the expression of proliferating cell nuclear antigen (PCNA) were observed by immunohistochemistry staining. RESULTS: Compare with control, thyroid gland showed proliferation of follicular epithelium in each experimental group, and the numbers of PCNA positive cells in thyroid gland significantly higher than that of control (P < 0.05). CONCLUSION: Perinatal exposure to sulphamethazine may affect the function of thyroid gland of offspring.


Assuntos
Exposição Materna , Efeitos Tardios da Exposição Pré-Natal , Sulfametazina/toxicidade , Glândula Tireoide/fisiologia , Animais , Anti-Infecciosos/toxicidade , Feminino , Masculino , Gravidez , Antígeno Nuclear de Célula em Proliferação/metabolismo , Ratos , Ratos Sprague-Dawley , Glândula Tireoide/metabolismo , Glândula Tireoide/patologia
19.
Am J Obstet Gynecol ; 201(6): 605.e1-8, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19766982

RESUMO

OBJECTIVE: The objective of the study was to assess the association between tea consumption and endometrial cancer. STUDY DESIGN: Studies were identified by searching PubMed and EMBASE databases and screening the references of retrieved articles. The summary relative risk (RR) with 95% confidence interval (CI) was calculated. RESULTS: The combined RR for ever drinkers vs non/lowest drinkers was 0.85 (95% CI, 0.77-0.94). Compared with non/lowest drinkers, the summary RR was 0.88 (95% CI, 0.78-0.98) for low to moderate drinkers and 0.75 (95% CI, 0.64-0.88) for high drinkers. An increase in tea intake of 2 cups/day was associated with a 25% decreased risk of endometrial cancer. In subgroup analyses, tea consumption was significantly associated with reduced endometrial cancer risk in Asian studies and studies using interviewing techniques. Furthermore, the protective effect of green tea on endometrial cancer seemed more evident than that of black tea. CONCLUSION: Findings from this metaanalysis suggest that tea consumption may reduce the risk of endometrial cancer. Because of the limited number of studies, further prospective studies are needed to explore the protective effect of tea on endometrial cancer.


Assuntos
Bebidas , Neoplasias do Endométrio/prevenção & controle , Chá , Estudos de Casos e Controles , Estudos de Coortes , Neoplasias do Endométrio/genética , Feminino , Humanos , Fatores de Risco
20.
Sichuan Da Xue Xue Bao Yi Xue Ban ; 36(3): 382-5, 2005 May.
Artigo em Chinês | MEDLINE | ID: mdl-15931875

RESUMO

OBJECTIVE: To investigate the adverse effects of perinatal exposure to nonylphenol (NP) on the reproductive development of F1 male SD rats in sexual maturation period. METHODS: The pregnant rats were randomly divided into control, 50 mg/kg, 100 mg/kg, and 200 mg/kg NP groups respectively. NP was administered to dams by gavage from gestation day 7 to weaning period. Rat pups were sacrificed at postnatal day 55. The concentration of serum testosterone was measured by radioimmunoassay. The epididymis was subjected to the determination of sperm count and motility while the testis was submitted to histopathological and immunohistochemical analyses. RESULTS: Compared with control, the concentration of serum testosterone, sperm count and motility in the 200 mg/kg NP dose groups significantly decreased (P < 0.05), and the histopathological examination revealed that NP-treated groups had higher rates of maldeveloped siminiferous tubules, smaller amount of Sertoli cells and weaker spermatogenesis. The expression of proliferative cell nuclear antigen (PCNA) significantly decreased in the 200 mg/kg NP dose groups (P < 0.05). The expression of Arom in 100 mg/kg and 200 mg/kg NP dose groups was lower than that in control. There was no significant difference in ER expression between the control and NP-treated groups. CONCLUSION: These findings indicated that 200 mg/kg Nonylphenol apparently damaged the reproductive development of F1 male SD rats in the sexual maturation period.


Assuntos
Fenóis/toxicidade , Maturidade Sexual/efeitos dos fármacos , Testosterona/sangue , Animais , Feminino , Masculino , Gravidez , Distribuição Aleatória , Ratos , Ratos Sprague-Dawley , Contagem de Espermatozoides , Maturação do Esperma
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