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1.
Int J Mol Med ; 2020 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-31922237

RESUMO

Age­related hearing loss, also termed central presbycusis, is a progressive neurodegenerative disease; it is a devastating disorder that severely affects the quality of life of elderly individuals. Substantial evidence has indicated that oxidative stress and associated protein folding dysfunction have a marked influence on neurodegenerative diseases. In this study, we aimed to cells to investigate whether metformin protects against age­related pathologies and to elucidate the underlying mechanisms; specifically, we focused on the role of unfolded protein response (UPR) via the AMPK/ERK1/2 signaling pathways. For this purpose, the biguanide compound, metformin, a medication widely used in the treatment of type 2 diabetes, was administered to rats in a model of mimetic aging. In addition, senescent PC12 were treated with metformin. Although it has been well established that UPR signaling is activated in response to cellular stress and is associated with the pathogenesis of neuronal deterioration, the detailed functions of the UPR in the auditory cortex remain unclear. We found that metformin treatment markedly affected the UPR and the AMPK/ERK1/2 signaling pathway, and maintained the auditory brainstem response (ABR) threshold during the aging process. The results indicated that the regulation of the UPR and AMPK/ERK1/2 signaling pathway by metformin significantly attenuated hearing loss, cell apoptosis and age­related neurodegeneration. Reversing these harmful effects through the use of metformin suggests its involvement in restoring the antioxidant status and protein homeostasis related to the underlying pathology of presbycusis. The findings of this study may provide a better approach for the treatment of age­related neurodegeneration diseases.

2.
J Healthc Eng ; 2019: 8526436, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31827742

RESUMO

Traumatic joint injury is known to cause cartilage deterioration and osteoarthritis. In order to study the mechanical mechanism of damage evolution on articular cartilage, taking the fresh porcine articular cartilage as the experimental samples, the creep experiments of the intact cartilages and the cartilages with different depth defect were carried out by using the noncontact digital image correlation technology. And then, the creep constitutive equations of cartilages were established. The results showed that the creep curves of different layers changed exponentially and were not coincident for the cartilage sample. The defect affected the strain values of the creep curves. The creep behavior of cartilage was dependent on defect depth. The deeper the defect was, the larger the strain value was. The built three-parameter viscoelastic constitutive equation had a good correlation with the experimental results and could predict the creep performance of the articular cartilage. The creep values of the microdefective cartilage in the damaged early stage were different from the diseased articular cartilage. These findings pointed out that defect could accelerate the damage of cartilage. It was helpful to study the mechanical mechanism of damage evolution.

3.
Sheng Wu Yi Xue Gong Cheng Xue Za Zhi ; 36(4): 590-595, 2019 Aug 25.
Artigo em Chinês | MEDLINE | ID: mdl-31441259

RESUMO

In order to study the mechanical behavior of degeneration and nucleotomy of lumbar intervertebral disc, compression experiments with porcine lumbar intervertebral discs were carried out. The lumbar intervertebral discs with trypsin-treated and nucleus nucleotomy served as the experimental group and the normal discs as the control group. Considering the effects of load magnitude and loading rate, the relationship between stress and strain, instantaneous elastic modulus and creep property of intervertebral disc were obtained. The creep constitutive model was established. The results show that the strain and creep strain of the experimental group increase significantly with the increase of compression load and loading rate, whereas the instantaneous elastic modulus decreases obviously, compared with the control group. It indicates that the effect of load magnitude and loading rate on load-bearing capacity of intervertebral disc after nucleotomy is larger obviously than that of normal disc. The creep behavior of the experimental group can be still predicted by the Kelvin three-parameter solid model. The results will provide theoretical foundation for clinical treatment and postoperative rehabilitation of intervertebral disc disease.


Assuntos
Disco Intervertebral/fisiologia , Disco Intervertebral/cirurgia , Estresse Mecânico , Animais , Fenômenos Biomecânicos , Vértebras Lombares , Suínos , Suporte de Carga
4.
Medicine (Baltimore) ; 98(27): e16302, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31277167

RESUMO

OBJECTIVE: Researchers have evaluated the associations between mitochondrial DNA (mtDNA) 4977 bp deletion and presbycusis. This study aimed to assess the differences of mtDNA 4977 bp deletion between presbycusis patients and controls by conducting a meta-analysis of published studies. METHODS: Databases, including PubMed, Embase, Web of Science, China National Knowledge Infrastructure (CNKI), and Wanfang Data were searched to collect case-control studies on the correlation between mitochondrial DNA 4977 bp deletion and presbycusis. The research findings of related articles were collected according to the inclusion criteria. Pooled odds ratios (ORs) and corresponding confidence intervals (CIs) were calculated. Meanwhile, subgroup analysis was performed to examine the source of heterogeneity. Revman 5.3 and Stata 12.0 software were used for data synthesis. RESULTS: Eight English and Chinese studies were included in the meta-analysis, the results of which showed that mitochondrial DNA 4977 bp deletion could increase the risk of presbycusis (OR = 8.16, 95% CI: 3.51-18.99), and the difference was statistically significant (P <. 01). Analysis of the polled OR showed the incidence of mtDNA 4977 bp deletion was 8.50 times higher in Asians with presbycusis than in the control group. And the OR in the studies of occidentals was 7.24. Sample source analysis was also performed with the sample source divided by temporal bone source and other sources (hair and blood). The OR was 4.18 and 22.36 for the temporal bone and other sources, respectively. CONCLUSION: Mitochondrial DNA 4977 bp deletion could increase the risk of presbycusis.


Assuntos
DNA Mitocondrial/genética , Presbiacusia/genética , Deleção de Sequência/genética , Estudos de Casos e Controles , Humanos
5.
Medicine (Baltimore) ; 98(25): e16128, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31232964

RESUMO

OBJECTIVE: The grainyhead-like-2 (GRHL2) genetic variants were reported in age-related hearing impairment (ARHI) susceptibility in several case-control studies. However, their conclusions are conflicting; it is difficult to precisely assess the disease risk associated with the variants. Therefore we conduct the meta-analysis to discover the association of GRHL2 polymorphisms and the risk of ARHI. METHODS: A related literature search was conducted in on-line databases, such as Wanfang database, China National Knowledge Infrastructure (CNKI), EMBASE, Web of Science, and PubMed (updated to August 30, 2018). We use Review Manager 5.0 and Stata SE 12.0 software to reckon the odds radio (OR), 95% confidence interval (CI) and P value in random- or fixed-effects model according to the I2 value in the heterogeneity test. RESULTS: 2762 cases and 2321 controls in 5 articles were provided data to the meta-analysis. The pooled ORs (95% CI) of the rs10955255 polymorphism were 1.26 (1.05-1.50, P = .01), 1.33 (1.07-1.65, P = .01), and 1.32 (1.12-1.55, P = .0007) in the allele, homozygote and recessive model separately. Besides, a significant association was detected between rs1981361 in mixed population and the ARHI risk in the allele, heterozygote, and dominant genetic model respectively. Then subgroup analyses was performed by ethnicity, for rs10955255 meaningful associations were detected for the allele model, homozygote model, dominant model and recessive model in the Caucasian population but no relations in any of the 5 genetic models in Asian population. CONCLUSION: The meta-analysis indicated that the rs10955255 polymorphism could be an important risk factor for ARHI, especially in the Caucasians. The rs1981361 polymorphism may be a risk factor for ARHI in Asians. Larger scale researches are needed to further bring the consequences up to date.


Assuntos
Fatores Etários , Proteínas de Ligação a DNA/genética , Perda Auditiva/genética , Fatores de Transcrição/genética , Estudos de Casos e Controles , Proteínas de Ligação a DNA/análise , Humanos , Polimorfismo de Nucleotídeo Único/fisiologia , Fatores de Risco , Fatores de Transcrição/análise
6.
Proc Inst Mech Eng H ; 233(8): 858-867, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31203788

RESUMO

The intervertebral disk cushions the load generated by human activity and absorbs energy to keep the spine moving steadily. Vibration condition is one of the important causes of disk degeneration. Creep experiments using the sheep lumbar intervertebral disk were carried out under vibration compression. Regularities of the strain of the disk with time were obtained and compared with those of static load. The influence of vibration frequency and time on the creep properties of the intervertebral disk was analyzed. An intervertebral disk three-parameter solid creep constitutive model considering vibration factors was established and the parameters in the model were identified. The results show that the strain of the lumbar intervertebral disk exhibits an exponential relationship with time and is unrelated to static compression or vibration load. Under the same vibration amplitude, the creep increases with vibration frequency and the relationship between them is nonlinear. The vibration frequency has a significant effect on the strain. The creep rate decreases gradually with time and is obviously influenced by vibration frequency at low vibration amplitudes. The creep prediction results obtained using the constitutive model with the time-varying material parameters are in good agreement with the experimental results. The two elastic moduli in the model decrease with time and the viscosity coefficient increases with time.


Assuntos
Força Compressiva , Disco Intervertebral/fisiologia , Vértebras Lombares/fisiologia , Teste de Materiais/métodos , Vibração , Animais , Fenômenos Biomecânicos , Disco Intervertebral/fisiopatologia , Deslocamento do Disco Intervertebral/fisiopatologia , Vértebras Lombares/fisiopatologia , Teste de Materiais/instrumentação , Ovinos , Suporte de Carga
7.
Sleep Breath ; 23(2): 559-565, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30343435

RESUMO

PURPOSE: Although mixed sleep apnea (MSA) is one of the three types of sleep apnea, it is not considered a separate disease entity. It is generally seen as a part of obstructive sleep apnea-hypopnea syndrome (OSAHS), but its implications are often ignored. In this study, we examined its features and the potential impact on OSAHS patients. METHODS: Subjects diagnosed with OSAHS by polysomnography (PSG) were enrolled. All participants underwent physical checkups and tests of blood biochemistry. They were anthropometrically, clinically, and polysomnographically studied. RESULTS: MSA events were common in patients with severe OSAHS patients. There were significant differences between the pure OSAHS group and its mixed counterpart in apnea-hypopnea indices during REM (AHIREM) and non-REM (AHINREM) and in percentages of N2 or N3 sleep. Logistic regression analysis showed that, after adjustment of other parameters, patients with MSA events were mostly male, had higher body mass index (BMI), higher scores on Epworth Sleepiness Scales (ESS), higher triglyceride (TG) levels, and higher apnea-hypopnea index (AHI). The combined predictive probability of the aforementioned variables was 0.766 (95% CI = 0.725~0.806; sensitivity 61.6%, specificity 82.1%). CONCLUSIONS: Our study suggested that MSA was related to the stability of the ventilatory control in OSAHS patients. MSA events occur more frequently in patients with severe OSAHS, and male gender, obesity, daytime sleepiness, and elevated TG levels were risk factors for the mixed OSAHS.

8.
Sleep Breath ; 23(2): 389-397, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29987514

RESUMO

BACKGROUND: Obstructive sleep apnea hypopnea syndrome (OSAHS) means apnea and hypopnea caused by partial or complete obstruction of upper airway collapse during sleep. Gastroesophageal reflux disease (GERD) is believed to be associated with various manifestations in the otorhinolaryngology and has been found to be an additional risk factor for OSAHS. AIM: A meta-analysis was performed to identify the association between obstructive sleep apnea hypopnea syndrome and gastroesophageal reflux disease. METHODS: To identify eligible original articles, we searched a series of computerized databases, including Medline via PubMed, EMBASE, Web of Science, and CNKI with a systematic searching strategy. The characteristics of each article and pooled odds ratios (ORs) with corresponding confidence intervals (CIs) were calculated and subgroup analysis was performed to analyze the source of heterogeneity. RESULTS: A total of 2699 patients from seven articles were included in the meta-analysis. We identified a significant relationship between obstructive sleep apnea syndrome and gastroesophageal reflux disease, with a pooled OR of 1.75 (95% CI 1.18-2.59, P < 0.05). The pooled data was calculated under the random-effects model as a significant moderate heterogeneity was found among the meta-analysis. CONCLUSIONS: The meta-analysis showed that there was a significant correlation between obstructive sleep apnea hypopnea syndrome and gastroesophageal reflux disease.

9.
Respir Res ; 19(1): 194, 2018 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-30285853

RESUMO

BACKGROUND: Obstructive sleep apnea-hypopnea syndrome (OSAHS) is prone to being complicated with various cardiovascular, cerebrovascular and metabolic conditions. OSAHS, due to its multifactorial nature, entails individualized and comprehensive treatment. So far, no well-established diagnostic criteria for the disease are available. In recent years, miRNA has been shown to be a sensitive biomarker suggestive of the progression and prognosis of many diseases. In this study, we examined some serum miRNAs in healthy OSAHS (OSAHS patients without complication) and OSAHS with arterial hypertension, with an attempt to understand the potential effects on the disease, improve the diagnosis of OSAHS and find OSAHS-related diagnostic markers. METHODS: Against various diagnostic criteria, participants were divided into three groups: healthy OSAHS, OSAHS with arterial hypertension and healthy controls. Their serum miRNA profiles were assessed by microarray technology, and then differentially expressed miRNAs were verified by quantitative real-time PCR (qRT-PCR). The receiver operating characteristic (ROC) curves of miRNAs were constructed and the areas under the curve (AUC) were calculated. Meanwhile, the miRNAs were subjected to logistic regression analysis. The target genes were bioinformatically assessed, their functions and signaling pathways further determined and eventually an miRNA-gene network was established. RESULTS: Analysis with the miRNA array exhibited that, compared with the control group, 12 differentially expressed miRNAs were found in healthy OSAHS, and 33 were found in OSAHS with arterial hypertension. The expression of miR-126-3p, let-7d-5p, miR-7641 and miR-1233-5p, miR-320b, miR-145-5p, miR-107, miR-26a-5p were validated by using qRT-PCR. Bioinformatics analysis predicted that the potential target genes of these miRNAs might be involved in metabolism, and the regulation of endothelial cells and nervous system. Moreover, the ROC analysis showed that the using miR-145-5p and let-7d-5p in combination can identify the healthy OSAHS, presence of miR-126-3p, miR-26a-5p and miR-107 was well indicative of OSAHS with arterial hypertension. CONCLUSIONS: A cluster of dysregulation miRNAs have been found to be involved in the development of OSAHS patients. Moreover, these miRNAs might be used to be potential diagnostic and early warning markers.


Assuntos
Perfilação da Expressão Gênica/métodos , Hipertensão/diagnóstico , Hipertensão/genética , MicroRNAs/genética , Apneia Obstrutiva do Sono/diagnóstico , Apneia Obstrutiva do Sono/genética , Adulto , Diagnóstico Precoce , Feminino , Redes Reguladoras de Genes/genética , Marcadores Genéticos/genética , Humanos , Hipertensão/metabolismo , Masculino , MicroRNAs/biossíntese , Pessoa de Meia-Idade , Síndromes da Apneia do Sono/diagnóstico , Síndromes da Apneia do Sono/genética , Síndromes da Apneia do Sono/metabolismo , Apneia Obstrutiva do Sono/metabolismo
10.
Diagn Pathol ; 12(1): 68, 2017 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-28923119

RESUMO

BACKGROUND: Inflammatory myofibroblastic tumor (IMT) of the stomach is extremely rare in adults and exhibits a variable biological behavior that ranges from frequently benign lesions to more aggressive variants. Here we report a case of gastric IMT with lymph node metastasis in an adult who had undergone total colectomy for familial adenomatous polyposis (FAP). CASE PRESENTATION: A 37-year-old man presented gradual-onset epigastric discomfort; he had undergone total colectomy for FAP 6 years before. The upper endoscopy revealed diffuse polyposis in the body of stomach and a submucosal protruding tumor of approximately 4.5 × 3.5 cm in the gastric angular incisure, appearing like gastrointestinal stromal tumor. Histology after surgery verified the diagnosis of fundic gland polyposis (FGPs) and gastric IMT with lymph node metastasis. Both the primary IMT tissue and its metastatic lesion but not the FGP or FAP tissue were positive for anaplastic lymphoma kinase (ALK) on immunohistochemical staining. Fluorescent in situ hybridization confirmed the existence of ALK rearrangement in IMT tissues. However, the patient exhibited no abnormalities in microsatellite instability or mismatch repair-system components, including MSH6, MSH2, MLH1 and PMS2, in IMT, FGP or FAP tissue. CONCLUSIONS: This case allowed for exploring the relationship among IMT, FGP and FAP and indicates that gastric IMT should be considered in the diagnosis of a gastric mass in patients with FAP. ALK may be a useful biomarker in the diagnosis of IMT and its metastatic lesions.


Assuntos
Polipose Adenomatosa do Colo/diagnóstico por imagem , Biomarcadores Tumorais/genética , Neoplasias de Tecido Muscular/diagnóstico por imagem , Pólipos/diagnóstico por imagem , Receptores Proteína Tirosina Quinases/genética , Neoplasias Gástricas/diagnóstico por imagem , Polipose Adenomatosa do Colo/patologia , Adulto , Quinase do Linfoma Anaplásico , Colectomia , Gastroscopia , Rearranjo Gênico , Humanos , Hibridização in Situ Fluorescente , Metástase Linfática , Masculino , Instabilidade de Microssatélites , Neoplasias de Tecido Muscular/patologia , Pólipos/patologia , Neoplasias Gástricas/patologia , Tomografia Computadorizada por Raios X , Ultrassonografia
11.
Inflammation ; 39(4): 1503-13, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27255374

RESUMO

Ischemic stroke can activate multiple transcription factors and cause inflammatory reactions, which involve pattern recognition receptors with immunostimulatory effects. Toll-like receptor 4 (TLR4) is one of the receptors related to innate immunity and several inflammatory reactions. The promising anti- inflammatory activity of salvianolic acid B (SAB) had been previously reported, but its effect on ischemic stroke remains unknown. An oxygen-glucose deprivation and reoxygenation (OGD/R) model in vitro and a middle cerebral artery occlusion (MCAO) model in vivo were used in this paper, and the results showned that SAB remarkably increased the viabilities of PC12 cells and primary cortical neurons after OGD/R injury and notably prevented cerebral ischemia/reperfusion (I/R) injury. SAB also significantly ameliorated NeuN release from primary cortical neurons. Further research indicated that the neuroprotection of SAB was completed through inhibiting the TLR4/MyD88/TRAF6 signaling pathway. The blocking of TLR4 by SAB also restrained NF-kB transcriptional activity and pro-inflammatory cytokine responses (IL-1ß, IL-6, and TNF-α). These findings supply a new insight that will aid in clarifying the effect of SAB against cerebral I/R injury and provide the development of SAB as a potential candidate for treating ischemic stroke.


Assuntos
Benzofuranos/farmacologia , Isquemia Encefálica/tratamento farmacológico , Fator 88 de Diferenciação Mieloide/metabolismo , Traumatismo por Reperfusão/prevenção & controle , Transdução de Sinais/efeitos dos fármacos , Receptor 4 Toll-Like/metabolismo , Animais , Anti-Inflamatórios/farmacologia , Células Cultivadas , Citocinas/metabolismo , Modelos Animais de Doenças , Infarto da Artéria Cerebral Média , Neurônios/citologia , Neurônios/metabolismo , Fármacos Neuroprotetores/farmacologia , Células PC12 , Ratos , Traumatismo por Reperfusão/tratamento farmacológico , Fator 6 Associado a Receptor de TNF/metabolismo
12.
J Air Waste Manag Assoc ; 65(11): 1297-305, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26284756

RESUMO

UNLABELLED: In this study, activated carbon was prepared from Chinese chestnut burs assisted by microwave irradiation with potassium hydroxide (KOH) as activator, and the process conditions were optimized employing Box-Behnken design (BBD) and response surface methodology (RSM). The optimized variables were irradiation time, impregnation time, and mass ratio of alkali-to-carbon, and the iodine adsorption value was used to evaluate the adsorption property of activated carbon. The optimal preparation conditions were determined as follows: irradiation time 17 min, impregnation time 240 min, and mass ratio of alkali-to-char 1.5:1. Meanwhile, the relatively high iodine adsorption value (1141.4 mg/g) was also obtained. Furthermore, the pore structural characterization of activated carbon was analyzed. The analyzed results showed a larger Brunauer-Emmett-Teller (BET) specific surface area (1254.5 m(2)/g) and a higher microporosity ratio (87.2%), a bigger total pore volume (0.6565 m(3)/g), but a smaller average pore size (2.093 nm), which demonstrated the obtained activated carbon possessed strong adsorption capacity and well-developed microporous structure. This research could not only establish the foundation of utilizing chestnut burs to prepare activated carbon, but also provide the basis for exploitation of Chinese chestnut by-products. IMPLICATIONS: Because Chinese chestnut burs are the by-products and usually discarded upon harvesting subsequently, the utilization of chestnut burs as a potential source of activated carbon is of great profit to the chestnut processing industries.


Assuntos
Carvão Vegetal/análise , Fagaceae/química , Micro-Ondas , Nozes/química , Adsorção , Hidróxidos/química , Porosidade , Compostos de Potássio/química
13.
Oncol Lett ; 9(6): 2713-2715, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26137133

RESUMO

A primary melanocytic lesion arising from the pleura is a rare occurrence. This is the case report of a 36-year-old female patient with a primary pleural melanocytic tumor. The positron emission tomography/computed tomography scan revealed multiple nodular soft tissue thickenings of the left hemipleura and a large amount of pleural effusion in the left hemithorax. The results of the histological examination confirmed the diagnosis of melanoma. The disease progressed 4 months following immunotherapy and chemotherapy and the patient succumbed to the disease 2 months later. This type of tumor appears to exhibit a highly aggressive biological behavior and responds poorly to immunotherapy and chemotherapy, which are characteristics similar to those exhibited by melanomas arising in other regions.

14.
Chaos ; 25(5): 053104, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-26026316

RESUMO

This paper sets up a chaos criterion theorem on a kind of cubic polynomial discrete maps. Using this theorem, Zhou-Song's chaos criterion theorem on quadratic polynomial discrete maps and generalized synchronization (GS) theorem construct an eight-dimensional chaotic GS system. Numerical simulations have been carried out to verify the effectiveness of theoretical results. The chaotic GS system is used to design a chaos-based pseudorandom number generator (CPRNG). Using FIPS 140-2 test suit/Generalized FIPS 140-2, test suit tests the randomness of two 1000 key streams consisting of 20 000 bits generated by the CPRNG, respectively. The results show that there are 99.9%/98.5% key streams to have passed the FIPS 140-2 test suit/Generalized FIPS 140-2 test. Numerical simulations show that the different keystreams have an average 50.001% same codes. The key space of the CPRNG is larger than 2(1345). As an application of the CPRNG, this study gives an image encryption example. Experimental results show that the linear coefficients between the plaintext and the ciphertext and the decrypted ciphertexts via the 100 key streams with perturbed keys are less than 0.00428. The result suggests that the decrypted texts via the keystreams generated via perturbed keys of the CPRNG are almost completely independent on the original image text, and brute attacks are needed to break the cryptographic system.

15.
Proc Inst Mech Eng H ; 228(5): 486-493, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24718863

RESUMO

The unconfined compression and tension experiments of the intervertebral disc were conducted by applying an optimized digital image correlation technique, and the internal strain distribution was analysed for the disc. It was found that the axial strain values of different positions increased obviously with the increase in loads, while inner annulus fibrosus and posterior annulus fibrosus experienced higher axial strains than the outer annulus fibrosus and anterior annulus fibrosus. Deep annulus fibrosus exhibited higher compressive and tensile axial strains than superficial annulus fibrosus for the anterior region, while there was an opposite result for the posterior region. It was noted that all samples demonstrated a nonlinear stress-strain profile in the process of deforming, and an elastic region was shown once the sample was deformed beyond its toe region.

16.
PLoS One ; 8(11): e78123, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24223767

RESUMO

Zinc Oxide Nanoparticles (ZnO NPs) have attracted increasing concerns because of their widespread use and toxic potential. In this study, Zn accumulations in different tissues (gills, liver, muscle, and gut) of goldfish (Carassius auratus) after exposure to ZnO NPs were studied in comparison with bulk ZnO and Zn(2+). And the technique of subcellular partitioning was firstly used on the liver of goldfish to study the hepatic accumulation of ZnO NPs. The results showed that at sublethal Zn concentration (2 mg/L), bioaccumulation in goldfish was tissue-specific and dependent on the exposure materials. Compared with Zn(2+), the particles of bulk ZnO and the ZnO NPs appeared to aggregate in the environmentally contacted tissues (gills and gut), rather than transport to the internal tissues (liver and muscle). The subcellular distributions of liver differed for the three exposure treatments. After ZnO NPs exposure, Zn percentage in metal-rich granule (MRG) increased significantly, and after Zn(2+) exposure, it increased significantly in the organelles. Metallothionein-like proteins (MTLP) were the main target for Zn(2+), while MRG played dominant role for ZnO NPs. The different results of subcellular distributions revealed that metal detoxification mechanisms of liver for ZnO NPs, bulk ZnO, and Zn(2+) were different. Overall, subcellular partitioning provided an interesting start to better understanding of the toxicity of nano- and conventional materials.


Assuntos
Carpa Dourada/metabolismo , Fígado/metabolismo , Nanopartículas/metabolismo , Poluentes Químicos da Água/metabolismo , Óxido de Zinco/metabolismo , Zinco/metabolismo , Animais , Cátions Bivalentes , Brânquias/efeitos dos fármacos , Brânquias/metabolismo , Inativação Metabólica , Mucosa Intestinal/metabolismo , Intestinos/efeitos dos fármacos , Fígado/efeitos dos fármacos , Metalotioneína/metabolismo , Músculos/efeitos dos fármacos , Músculos/metabolismo , Nanopartículas/toxicidade , Poluentes Químicos da Água/farmacocinética , Poluentes Químicos da Água/toxicidade , Zinco/farmacocinética , Zinco/toxicidade , Óxido de Zinco/farmacocinética , Óxido de Zinco/toxicidade
17.
Histopathology ; 63(3): 325-33, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23829397

RESUMO

AIMS: This study aimed to examine the involvement of glucose-regulated protein 94 (GRP94) in oestrogen receptor-α36 (ER-α36)-mediated oestrogen signalling in gastric cancer development. METHODS AND RESULTS: A total of 130 formalin-fixed and paraffin-embedded gastric tumour samples with corresponding normal gastric and tumour-adjacent tissues were used. High levels of GRP94 expression (2+ or 3+) were observed in 109 of 130 gastric carcinomas (83.85%) by immunohistochemistry, and in 13 of 18 tumour specimens (72.22%) with Western blot analysis. GRP94 expression was correlated positively with gender, tumour stage, lymph node metastasis and ER-α36 expression (P < 0.05). Oestrogen treatment up-regulated both GRP94 and ER-α36 expression in gastric cancer SGC7901 cells. In addition, steady state levels of GRP94 protein were decreased in established gastric cancer SGC7901 cells with knocked-down levels of ER-α36 expression and in xenograft tumours formed by these cells. Forced expression of recombinant ER-α36 in SGC7901 cells, however, up-regulated the levels of GRP94 expression. CONCLUSIONS: Glucose-regulated protein 94 is a downstream effector of ER-α36-mediated oestrogen signalling, and may be involved in ER-α36 function during gastric carcinogenesis.


Assuntos
Receptor alfa de Estrogênio/metabolismo , Glicoproteínas de Membrana/metabolismo , Neoplasias Gástricas/metabolismo , Adenocarcinoma/etiologia , Adenocarcinoma/metabolismo , Adenocarcinoma/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Animais , Western Blotting , Carcinogênese , Linhagem Celular Tumoral , Receptor alfa de Estrogênio/antagonistas & inibidores , Receptor alfa de Estrogênio/genética , Feminino , Técnicas de Silenciamento de Genes , Xenoenxertos , Humanos , Imuno-Histoquímica , Metástase Linfática , Masculino , Camundongos , Camundongos Nus , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Transdução de Sinais , Neoplasias Gástricas/etiologia , Neoplasias Gástricas/patologia , Regulação para Cima
18.
J Huazhong Univ Sci Technolog Med Sci ; 33(3): 379-384, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23771664

RESUMO

The specimens of ductal carcinoma in situ (DCIS) with early invasion, and specimens collected by core needle biopsy (CNB) tend to contain limited amount of invasive component, so it is imperative to explore a new technique which can assess HER2 gene status accurately for the limited invasive cancer component in these specimens. Dual staining technique of combining immunohistochemistry (IHC) for myoepithelial cells and single or dual probe chromogenic in situ hybridization (CISH) for HER2 gene was performed on routinely processed paraffin sections from 20 cases diagnosed as having DCIS with invasive cancer. Among them, 10 had fluorescence in situ hybridization (FISH)-confirmed amplification of HER2 and 10 had FISH-confirmed non-amplification of HER2. We successfully detected HER2 genetic signals and myoepithelial IHC markers (SMM-HC or CK5/6) simultaneously on a single section in all 20 specimens. Myoepithelial markers and HER2 signals detected by dual staining assay were consistent with those by individual technique performed alone. HER2 gene amplification results determined by dual staining assay were 100% consistent with those of FISH. Dual staining technique which allows simultaneous detection of myoepithelial marker protein and cancerous HER2 gene is feasible, and it has potential to be used in clinical practice for effective determination of HER2 amplification in limited invasive component.


Assuntos
Biomarcadores Tumorais/metabolismo , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Imuno-Histoquímica/métodos , Hibridização in Situ Fluorescente/métodos , Receptor ErbB-2/metabolismo , Neoplasias da Mama/genética , Compostos Cromogênicos , Feminino , Perfilação da Expressão Gênica/métodos , Humanos , Invasividade Neoplásica/patologia , Invasividade Neoplásica/fisiopatologia , Receptor ErbB-2/genética , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
19.
Water Res ; 46(18): 5981-8, 2012 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-22999974

RESUMO

Great progress has been made in the controlled fabrication of nanomaterials with given sizes, shapes, and geometries. However, how such changes in structure potentially affect the bioavailability and toxicity of metal nanoparticles to aquatic organisms remains mostly unknown. The present study reports the different behaviors of two types of Cu(2)O micro/nanocrystals (micro/nano-Cu(2)O) with different shapes (cubic and octahedral) and crystallographies (with exposed surfaces as {100} or {111}). The bioaccumulation, median lethal concentration, and biomarker responses of Daphnia magna exposed to the two micro/nanocrystals are also investigated. The Cu accumulation, production of metallothionein (MT), and inhibition ratio of D. magna increased gradually with increasing micro/nano-Cu(2)O concentration. The two crystals showed slight Cu accumulation differences toward D. magna, and their biomarker responses and toxicities to D. magna differed significantly as well. The octahedral Cu(2)O micro/nanocrystals were more toxic to D. magna compared with the cubic micro/nanocrystals probably because of the higher surface activities of the {111} facets compared with those of the {100} facets for cuprites. Food ingestion was the main entry pathway of the micro/nanocrystals into organisms, and toxicity was consequently determined based on the dissolution behavior of the micro/nanocrystals in vivo.


Assuntos
Cobre/química , Cobre/toxicidade , Daphnia/efeitos dos fármacos , Nanopartículas/química , Nanopartículas/toxicidade , Poluentes Químicos da Água/química , Poluentes Químicos da Água/toxicidade , Animais , Daphnia/metabolismo , Metalotioneína/metabolismo
20.
Nat Prod Res ; 25(17): 1662-5, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21790497

RESUMO

Extraction of roots of Patrinia rupestris (Pall.) Juss. gave a new iridoid compound, 1ß,3α-diethyloxy-7-hydromethyl-4-(3-methyl-butyryloxymethyl)-cyclopenta-4(4a),7(7a)-diene[c]pyran-6-one (1), together with a known compound, (1α,4aα, 6α,7ß,7aα)-[4a,5,6,7,7a-hexahydro-6,7-dihydroxy-1-(3-methyl-1-oxobutoxy) cyclopenta[c]pyran-4,7-diyl]bis(methylene) 3-methyl-butanoic acid ester (2). The structure of 1 was characterised by HRESIMS, IR, UV, 1-D NMR and 2-D NMR methods. Compound 2 was isolated from this genus for the first time.


Assuntos
Iridoides/isolamento & purificação , Patrinia/química , Extratos Vegetais/isolamento & purificação , Raízes de Plantas/química , Iridoides/análise , Espectroscopia de Ressonância Magnética , Estrutura Molecular , Extratos Vegetais/análise , Espectrometria de Massas por Ionização por Electrospray , Espectrofotometria Infravermelho , Espectrofotometria Ultravioleta
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