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1.
Pediatr Transplant ; 21(7)2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28449371

RESUMO

Results on the relationship between CTLA4 -318C/T (rs5742909) gene polymorphism and risk of acute rejection in renal transplantation are still conflicting. This meta-analysis was performed to update the association between CTLA4 -318C/T and risk of acute rejection in renal transplantation. The association investigations were identified from PubMed and Cochrane Library, and eligible studies were included and synthesized using meta-analysis method. Twelve reports were included in this meta-analysis for the association of CTLA4 -318C/T gene polymorphism with acute rejection risk in renal transplantation, consisting of 728 acute rejection patients and 1628 non-acute rejection controls. The association between CTLA4 -318C/T gene polymorphism and acute rejection risk in renal transplantation for overall populations was not found in this meta-analysis (T allele: OR=0.96, 95% CI: 0.60-1.54, P=.88; TT genotype: OR=0.90, 95% CI: 0.47-1.71, P=.74; CC genotype: OR=1.00, 95% CI: 0.62-1.59, P=.98). Interestingly, T allele was associated with the risk of acute rejection in renal transplantation in African population. In conclusion, CTLA4 -318C/T gene polymorphism is not associated with the risk of acute rejection in renal transplantation in overall populations.


Assuntos
Antígeno CTLA-4/genética , Rejeição de Enxerto/genética , Transplante de Rim , Polimorfismo Genético , Marcadores Genéticos , Humanos , Fatores de Risco
3.
Int J Mol Sci ; 17(2): 170, 2016 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-26861301

RESUMO

Intercellular communication was long thought to be regulated exclusively through direct contact between cells or via release of soluble molecules that transmit the signal by binding to a suitable receptor on the target cell, and/or via uptake into that cell. With the discovery of small secreted vesicular structures that contain complex cargo, both in their lumen and the lipid membrane that surrounds them, a new frontier of signal transduction was discovered. These "extracellular vesicles" (EV) were initially thought to be garbage bags through which the cell ejected its waste. Whilst this is a major function of one type of EV, i.e., apoptotic bodies, many EVs have intricate functions in intercellular communication and compound exchange; although their physiological roles are still ill-defined. Additionally, it is now becoming increasingly clear that EVs mediate disease progression and therefore studying EVs has ignited significant interests among researchers from various fields of life sciences. Consequently, the research effort into the pathogenic roles of EVs is significantly higher even though their protective roles are not well established. The "Focus on extracellular vesicles" series of reviews highlights the current state of the art regarding various topics in EV research, whilst this review serves as an introductory overview of EVs, their biogenesis and molecular composition.


Assuntos
Comunicação Celular , Vesículas Extracelulares/metabolismo , Animais , Apoptose , Transporte Biológico , Biotecnologia , Fracionamento Celular/métodos , Exossomos/metabolismo , Humanos , Pesquisa , Transdução de Sinais
4.
Int J Mol Sci ; 17(2): 172, 2016 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-26861303

RESUMO

Many types of cells release phospholipid membrane vesicles thought to play key roles in cell-cell communication, antigen presentation, and the spread of infectious agents. Extracellular vesicles (EVs) carry various proteins, messenger RNAs (mRNAs), and microRNAs (miRNAs), like a "message in a bottle" to cells in remote locations. The encapsulated molecules are protected from multiple types of degradative enzymes in body fluids, making EVs ideal for delivering drugs. This review presents an overview of the potential roles of EVs as natural drugs and novel drug-delivery systems.


Assuntos
Sistemas de Liberação de Medicamentos , Vesículas Extracelulares/metabolismo , Animais , Células Apresentadoras de Antígenos/metabolismo , Transporte Biológico , Ensaios Clínicos como Assunto , Exossomos/metabolismo , Humanos , Neoplasias/imunologia , Neoplasias/metabolismo , Neoplasias/terapia , Células-Tronco/metabolismo
5.
Biomarkers ; 20(6-7): 487-94, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26616150

RESUMO

Breast cancer is currently the second most common cancer worldwide and the most frequent malignant tumor among women. However, the exact contribution of various allelic alterations remains unclear. This meta-analysis was conducted to evaluate the association of the transforming growth factor ß receptor I 6A/9A (TßR-I 6A/9A) gene polymorphism with breast cancer risk. Relevant studies were identified from PubMed and Cochrane Library on 1 October 2013, and eligible reports were recruited and synthesized. Eleven reports that included a total of 12 studies were recruited into this meta-analysis for the association of the TßR-I 6A/9A gene polymorphism and breast cancer risk. The results indicated that overall the TßR-I 6A allele was associated with breast cancer risk (OR = 1.33, 95% CI: 1.02-1.73, p = 0.04). However, the TßR-I 6A/6A and 9A/9A genotypes were not associated with an increased risk of developing breast cancer (6A/6A: OR = 1.71, 95% CI: 0.95-3.08, p = 0.07; 9A/9A: OR = 0.82, 95% CI: 0.66-1.02, p = 0.08). In the Caucasian population, no such association could be established. In conclusion, the TßR-I 6A allele might represent a risk factor for breast cancer risk, but significantly larger data sets from a larger number of studies, including studies that allow ethnicity, subgroup analysis and environmental impact evaluation, are required to maximize statistical significance and meta-analysis robustness.


Assuntos
Neoplasias da Mama/genética , Predisposição Genética para Doença/genética , Polimorfismo Genético , Proteínas Serina-Treonina Quinases/genética , Receptores de Fatores de Crescimento Transformadores beta/genética , Alelos , Feminino , Frequência do Gene , Genótipo , Humanos , Razão de Chances , Receptor do Fator de Crescimento Transformador beta Tipo I , Medição de Risco , Fatores de Risco
6.
Ren Fail ; 37(8): 1247-59, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26161693

RESUMO

Methylenetetrahydrofolate reductase (MTHFR) is a crucial enzyme that regulates nucleotide synthesis and DNA methylation. The MTHFR C677T gene polymorphism (rs1801133), a C → T transition at nucleotide 677 in exon 4, is a common gene variant of MTHFR and has been implicated in diabetic nephropathy, albeit with inconsistent results. Here, we performed a meta-analysis to assess the common effect size of this polymorphism on DN susceptibility. Case-control studies on the association of the MTHFR C677T gene polymorphism with DN risk were retrieved from databases up to August 1, 2013, and eligible studies were recruited into the meta-analysis and further analyzed. Of 132 studies, 33 were identified as suitable for this analysis. The results showed that T allele and TT genotype were distinctly associated with DN susceptibility in the overall population and Asians, and might be a risk factor in Caucasians and Africans (T allele: Overall population: p < 0.00001, Asians: p = 0.0002, Caucasians: p = 0.02, Africans: p < 0.00001; TT genotype: Overall population: p < 0.00001, Asians: p = 0.0003, Caucasians: p = 0.008, Africans: p = 0.0003). Furthermore, the analysis suggested that the CC genotype might play a protective role against DN onset in patients with type 2 diabetes for the overall population, Asians, Caucasian and Africans. However, due to the limited sample size in the African population, these results should be interpreted with care. In conclusion, the MTHFR C677T T allele or TT genotype might be a significant genetic molecular marker to determine the risk of DN in patients with type 2 diabetes and help to develop suitable disease prevention and management strategies.


Assuntos
Nefropatias Diabéticas/genética , Metilenotetra-Hidrofolato Redutase (NADPH2)/genética , Grupos Raciais/genética , Alelos , Biomarcadores , Diabetes Mellitus Tipo 2/complicações , Nefropatias Diabéticas/diagnóstico , Predisposição Genética para Doença , Humanos , Polimorfismo de Nucleotídeo Único , Fatores de Risco
7.
Am J Physiol Renal Physiol ; 306(12): F1477-88, 2014 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-24785190

RESUMO

LIM homeobox transcription factor 1B (LMX1B) is a transcription factor of the LIM homeodomain type and has been implicated in the development of diverse structures such as limbs, kidneys, eyes, and the brain. Furthermore, LMX1B has been implicated in nail-patella syndrome, which is predominantly characterized by malformation of limbs and nails, and in 30% of patients, nephropathy, including renal fibrosis, is observed. Since no reports were available that studied the link between LMX1B expression and renal interstitial fibrosis, we explored if LMX1B affects typical markers of fibrosis, e.g., extracellular matrix components, profibrotic factors, and apoptosis as the final detrimental consequence. We recently showed that LMX1B acts as a negative regulator of transforming growth factor-ßl, collagen type III, fibronectin, cleaved caspase-3, and the cell apoptosis rate in a renal tubular epithelial cell system under hypoxic conditions. Here, we confirmed these results in unilateral ureteral obstructed rats. Furthermore, LMX1B was distinctly expressed throughout the glomerulus and tubule lining, including epithelial cells. Knockdown of LMX1B aggravated the expression of fibrosis markers, oxidative stress, and apoptosis compared with the already increased levels due to unilateral ureteral obstruction, whereas overexpression attenuated these effects. In conclusion, reduced LMX1B levels clearly represent a risk factor for renal fibrosis, whereas overexpression affords some level of protection. In general, LMX1B may be considered to be a negative regulator of the fibrosis index, transforming growth factor-ßl, collagen type III, fibronectin, cleaved caspase-3, cell apoptosis, ROS, and malondialdehyde (r = -0.756, -0.698, -0.921, -0.923, -0.843, -0.794, -0.883, and -0.825, all P < 0.01).


Assuntos
Apoptose , Rim/metabolismo , Rim/patologia , Proteínas com Homeodomínio LIM/metabolismo , Fatores de Transcrição/metabolismo , Obstrução Ureteral/metabolismo , Obstrução Ureteral/patologia , Animais , Biomarcadores/metabolismo , Colágeno Tipo III/metabolismo , Modelos Animais de Doenças , Fibronectinas/metabolismo , Fibrose , Masculino , Estresse Oxidativo/fisiologia , Ratos , Ratos Wistar , Espécies Reativas de Oxigênio/metabolismo , Fatores de Risco , Fator de Crescimento Transformador beta1/metabolismo , Obstrução Ureteral/fisiopatologia
8.
Am J Epidemiol ; 180(1): 1-10, 2014 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-24907267

RESUMO

A possible association between glutathione S-transferase theta 1 gene (GSTT1) polymorphism and the risk of developing prostate cancer is currently hotly debated, but evidence from various epidemiologic studies remains unclear. This investigation was performed to assess whether an association between GSTT1 polymorphism and prostate cancer risk exists by using meta-analysis to combine comparable studies, thereby increasing sample size and statistical significance, as well as to identify patterns in various studies. The association reports were identified from the PubMed database and the Cochrane Library on March 1, 2013, and data from eligible studies (from 1999-2012) were synthesized. Thirty-eight reports were included in this meta-analysis on the association of the null genotype of GSTT1 with prostate cancer risk. No solid association between the GSTT1 null genotype and prostate cancer risk could be established for the overall population (odds ratio = 1.11, 95% confidence interval: 0.97, 1.27; P = 0.13). However, the GSTT1 null genotype was distinctly associated with prostate cancer risk in Caucasians (odds ratio = 1.24, 95% confidence interval: 1.03, 1.48, P = 0.02). In conclusion, the GSTT1 null genotype is associated with prostate cancer risk in Caucasians, but not in the overall population.


Assuntos
Glutationa Transferase/genética , Neoplasias da Próstata/genética , Estudos de Associação Genética , Predisposição Genética para Doença/genética , Humanos , Masculino , Polimorfismo Genético/genética , Fatores de Risco , População Branca/genética
9.
Apoptosis ; 19(4): 594-602, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24310985

RESUMO

LIM homeobox transcription factor 1B (LMX1B) is a transcription factor of the LIM-homeodomain type, which plays an important role in foetal development during formation of the extremities, kidneys, eyes, and the brain. Furthermore, LMX1B has been implicated in nail-patella syndrome, which is predominantly characterized by malformation of limbs and nails, and in 30 % of patients, nephropathy, including renal fibrosis, is observed. Since no reports were available that studied the link between LMX1B expression and pro-fibrotic components and apoptosis in hypoxic renal tubular epithelial cells (RTEC), we explored if LMX1B was associated with extracellular matrix components, profibrotic factors, and apoptosis induced by hypoxia/reoxygenation (H-R). In this cell system under hypoxic conditions, when the expression of LMX1B was inhibited in H-R RTEC, the expression of transforming growth factor-ßl, collagen-III, fibronectin, cleaved caspase-3, and cell apoptosis rate was increased. Consequently, overexpression of LMX1B was associated with reduced cell apoptosis, whilst downregulation of LMX1B was associated with increased cell apoptosis in H-R RTEC.


Assuntos
Apoptose/fisiologia , Células Epiteliais/patologia , Matriz Extracelular/metabolismo , Túbulos Renais/patologia , Proteínas com Homeodomínio LIM/metabolismo , Fatores de Transcrição/metabolismo , Animais , Hipóxia Celular , Linhagem Celular , Células Epiteliais/metabolismo , Fibrose , Túbulos Renais/metabolismo , Proteínas com Homeodomínio LIM/genética , Estresse Oxidativo , Ratos , Fatores de Transcrição/genética
10.
J Recept Signal Transduct Res ; 34(6): 469-75, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24840097

RESUMO

The association of transforming growth factor-ß1 (TGFß1) is an important signaling pathway factor involving extracellular matrix regulation, and its gene polymorphisms with the risk of rheumatoid arthritis (RA) is currently still fiercely debated. Therefore, this meta-analysis was performed to determine if TGFß1 T869C, G915C, and C509T gene polymorphisms correlate with the risk of developing RA. Association reports were identified from PubMed, Cochrane Library and CBM-disc (China Biological Medicine Database) on 1 May 2013, and eligible studies were recruited and synthesized to identifying patterns among study results. T869C TT genotype in the overall population was associated with increased RA risk (OR = 1.28, 95% CI: 1.02-1.60, p = 0.03). In the sub-group analysis, T869C TT genotype was shown to be a risk factor for RA, and T869C C allele or CC genotype a protective factor against RA disease in Asians, but these associations were not found in Caucasians. Furthermore, TGFß1 C509T TT genotype was distinctly associated with RA susceptibility, but the T allele and CC genotype were not. TGFß1 G915C gene polymorphism was not associated with RA susceptibility. In conclusion, the TT genotype of TGFß1 T869C was associated with RA risk in the overall population and Asians. Furthermore, CC genotype or C allele was determined to be protective factors with respect to the RA risk in the overall population and Asians. Nonetheless, additional studies are required to firmly establish a correlation between the aforementioned polymorphisms and RA risk.


Assuntos
Artrite Reumatoide/epidemiologia , Artrite Reumatoide/genética , Predisposição Genética para Doença/epidemiologia , Predisposição Genética para Doença/genética , Polimorfismo de Nucleotídeo Único/genética , Fator de Crescimento Transformador beta1/genética , China/epidemiologia , Estudos de Associação Genética , Marcadores Genéticos/genética , Humanos , Incidência , Reprodutibilidade dos Testes , Fatores de Risco , Sensibilidade e Especificidade
11.
Mol Biol Rep ; 41(5): 3033-43, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24595445

RESUMO

Prohibitins PHB1 and PHB2 are evolutionary conserved and pleiotropic proteins, which have been shown to be important factors in various cellular functions, including proliferation, tumour suppression, apoptosis, transcription, and mitochondrial protein folding. Recently, we demonstrated that down-regulation promoted renal interstitial fibrosis (RIF) in ureteral obstructed rats. Furthermore, the hypoxic conditions and oxidative stress have been implicated in obstruction-mediated renal disease. This study was performed to explore the association of PHBs with oxidative stress in a rat model of RIF. PHBs, the pro-fibrotic transforming growth factor-ß1 (TGF-ß1), and the extracellular matrix proteins collagen-IV (Col-IV) and fibronectin (FN) were evaluated, as were markers of oxidative stress [total reactive oxygen species (ROS), malondialdehyde (MDA)] and antioxidative capacity (superoxide dismutase, glutathione), and apoptosis. Our results showed a progressive increase in oxidative stress and concomitant decrease in antioxidants over a period of 4 weeks ureteral obstruction. Concomitantly, profibrotic components increased and PHB expression decreased. Overall, both PHBs were negatively correlated with the extent of observed fibrosis, TGF-ß1, Col-IV, FN, ROS, MDA, and apoptosis.


Assuntos
Nefropatias/genética , Nefropatias/metabolismo , Estresse Oxidativo , Proteínas Repressoras/genética , Animais , Apoptose/genética , Modelos Animais de Doenças , Matriz Extracelular/metabolismo , Fibrose , Nefropatias/patologia , Masculino , Proibitinas , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Ratos , Proteínas Repressoras/metabolismo , Fator de Crescimento Transformador beta1/metabolismo
12.
Mol Biol Rep ; 41(2): 639-49, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24352702

RESUMO

A possible association of glutathione S-transferase T1 (GSTT1) null/presence gene polymorphism and an increased risk of developing gastric carcinoma is still unclear and hotly debated. This investigation was performed to assess the association of the GSTT1 null/presence gene polymorphism with the risk of gastric carcinoma via a meta-analysis to increase sample size and statistical significance. PubMed, Cochrane Library and CBM-disc (China Biological Medicine Database) were searched on March 1, 2013, association reports were identified, and eligible studies were recruited and synthesized. Fifty-two reports were found to be suitable for this meta-analysis for the association of the GSTT1 null genotype with gastric carcinoma risk. The results showed that there was a significantly increased gastric carcinoma risk when the GSTT1 null genotype was present in the overall population (OR 1.21, 95 % CI 1.11-1.32, P < 0.0001), Caucasians (OR 1.25, 95 % CI 1.05-1.48, P = 0.01), East-Asians (OR 1.18, 95 % CI 1.06-1.31, P = 0.003), and Chinese (OR 1.24, 95 % CI 1.07-1.44, P = 0.005). However, no statistically relevant association could be established for the Indian ethnic group (OR 1.33, 95 % CI 0.94-1.90, P = 0.11). In conclusion, the GSTT1 null genotype is associated with an increased gastric carcinoma risk in the overall population, Caucasians, East-Asians, and Chinese.


Assuntos
Estudos de Associação Genética , Glutationa Transferase/genética , Neoplasias Gástricas/genética , Povo Asiático/genética , Carcinoma , China , Predisposição Genética para Doença , Genótipo , Humanos , Polimorfismo Genético , Fatores de Risco , Neoplasias Gástricas/patologia , População Branca/genética
13.
Nephrology (Carlton) ; 19(2): 107-15, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24428217

RESUMO

AIM: A possible association between the transforming growth factor-ß1 (TGF-ß1) T869C gene polymorphism and the risk of developing diabetic nephropathy (DN) remains unclear. This investigation was performed to assess if an association between the TGF-ß1 T869C gene polymorphism and DN risk exists by using meta-analysis to combine comparable studies, thereby increasing sample size and statistical significance, and to identify patterns in various studies. METHODS: The association reports were identified from PubMed, Cochrane Library, and CBM-disc (China Biological Medicine Database) on 1 May 2013, and eligible studies were recruited and synthesized. RESULTS: Fifty reports were recruited into this meta-analysis for the association of the TGF-ß1 T869C gene polymorphism with DN risk. The TT genotype in the overall population was shown to be associated with DN risk (odds ratio (OR) = 0.74, 95% confidence interval (CI): 0.56-0.98, P = 0.04). In the sub-group analysis, CC genotype was associated with DN risk in Asians, Caucasians, and Africans. However, the sample size for Caucasians and Africans was relatively small. Furthermore, T allele was distinctly associated with the risk of developing DN in the Asian population (OR = 0.76, 95% CI: 0.62-0.92, P = 0.005). CONCLUSIONS: The TT genotype of TGF-ß1 T869C in the overall population was associated with DN risk, whereas the CC genotype and T allele were distinctly associated with DN risk in the Asian population. Nonetheless, additional studies are required to firmly establish a correlation between the aforementioned polymorphism and DN risk.


Assuntos
Nefropatias Diabéticas/genética , Predisposição Genética para Doença , Polimorfismo Genético , Fator de Crescimento Transformador beta1/genética , Nefropatias Diabéticas/etiologia , Genótipo , Humanos , Viés de Publicação , Risco
14.
J Recept Signal Transduct Res ; 33(6): 349-52, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24050824

RESUMO

Peroxisome proliferator-activated receptor-γ (PPARγ), belongs to the nuclear receptor superfamily, and is a nuclear transcription receptor involving in the regulation of several biochemical pathways, such as cell growth, differentiation, and apoptosis. The nuclear retinoic acid receptors (RARs) are transcriptional transregulators that control the expression of specific subsets of genes in a ligand-dependent manner, and include three subtypes (RARα, RARß, and RARγ). These control the expression of specific gene subsets subsequent to ligand binding and to strictly control phosphorylation processes. The current status of knowledge indicates that there might be inter- or overlapping actions between PPARγ and RARs, and there might be an association of PPARγ/RARs with renal diseases. Various agonists of both receptor families seem to prevent or retard the progression of renal disease. Herein, we review if causal relationships can be established between PPARγ/RARs and renal diseases and its manifestations.


Assuntos
Nefropatias/genética , PPAR gama/metabolismo , Receptores do Ácido Retinoico/metabolismo , Apoptose/genética , Diferenciação Celular/genética , Proliferação de Células , Humanos , Nefropatias/patologia , PPAR gama/genética , Receptores do Ácido Retinoico/genética , Receptor alfa de Ácido Retinoico , Transcrição Gênica , Receptor gama de Ácido Retinoico
15.
Int J Mol Sci ; 14(10): 19399-415, 2013 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-24071940

RESUMO

The aim of this study was to evaluate the in cellulo inhibition of hydrogen-peroxide-induced oxidative stress in skin fibroblasts using different low-molecular-weight polysaccharides (LMPS) prepared from agar (LMAG), chitosan (LMCH) and starch (LMST), which contain various different functional groups (i.e., sulfate, amine, and hydroxyl groups). The following parameters were evaluated: cell viability, intracellular oxidant production, lipid peroxidation, and DNA damage. Trolox was used as a positive control in order to allow comparison of the antioxidant efficacies of the various LMPS. The experimentally determined attenuation of oxidative stress by LMPS in skin fibroblasts was: LMCH > LMAG > LMST. The different protection levels of these LMPS may be due to the physic-chemical properties of the LMPS' functional groups, including electron transfer ability, metal ion chelating capacities, radical stabilizing capacity, and the hydrophobicity of the constituent sugars. The results suggest that LMCH might constitute a novel and potential dermal therapeutic and sun-protective agent.


Assuntos
Fibroblastos/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Polissacarídeos/farmacologia , Pele/efeitos dos fármacos , Antioxidantes/metabolismo , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Dano ao DNA/efeitos dos fármacos , Transporte de Elétrons/efeitos dos fármacos , Fibroblastos/metabolismo , Radicais Livres/metabolismo , Humanos , Peróxido de Hidrogênio/farmacologia , Interações Hidrofóbicas e Hidrofílicas/efeitos dos fármacos , Quelantes de Ferro/metabolismo , Peroxidação de Lipídeos/efeitos dos fármacos , Peso Molecular , Pele/metabolismo
16.
Int J Mol Sci ; 14(1): 226-43, 2012 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-23344030

RESUMO

Fibrotic diseases, such as liver, pulmonary and renal fibrosis, are common end-stage conditions and represent a major global health problem. Furthermore, effective therapeutic measures are presently unavailable. Extracellular matrix accumulation is the most prominent characteristic in the pathogenesis of fibrotic disease. Retinoic acid, including all-trans retinoic acid, 9-cis and 13-cis retinoic acid, play important roles in various physiological processes, such as in embryonic development, reproduction, vision, cell growth, differentiation, apoptosis and inflammation. Present studies report that retinoic acid treatment may affect various processes involved in the onset and progression of fibrotic disease. However, the therapeutic effects of retinoic acid in such diseases remain controversial. Several reports indicate that retinoic acid positively affects the progression of fibrosis and alleviates the accumulation of the extracellular matrix, whereas other studies report the opposite; that retinoic acid exacerbates fibrosis and induces extracellular matrix accumulation. Signaling pathways might be an important influencing factor and differences in signaling events might be responsible for the contradictory role of retinoic acid in fibrotic diseases. Since there was no review available that investigated the role of retinoic acid and the signaling pathways involved, we retrospectively studied the literature and provide a comprehensive analysis of retinoic acid's role in fibrotic diseases, and provide an overview of the signal transduction pathways involved in its pathogenesis.


Assuntos
Fibrose/metabolismo , Transdução de Sinais , Tretinoína/metabolismo , Animais , Matriz Extracelular/metabolismo , Humanos , Especificidade de Órgãos
17.
Int J Mol Sci ; 13(10): 12412-27, 2012 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-23202906

RESUMO

Zinc sulfide semiconductor nanoparticles were synthesized in an aqueous solution of polyvinyl pyrrolidone via a simple microwave irradiation method. The effect of the polymer concentration and the type of sulfur source on the particle size and dispersion of the final ZnS nanoparticle product was carefully examined. Microwave heating generally occurs by two main mechanisms: dipolar polarization of water and ionic conduction of precursors. The introduction of the polymer affects the heating rate by restriction of the rotational motion of dipole molecules and immobilization of ions. Consequently, our results show that the presence of the polymer strongly affects the nucleation and growth rates of the ZnS nanoparticles and therefore determines the average particle size and the dispersion. Moreover, we found that PVP adsorbed on the surface of the ZnS nanoparticles by interaction of the C-N and C=O with the nanoparticle's surface, thereby affording protection from agglomeration by steric hindrance. Generally, with increasing PVP concentration, mono-dispersed colloidal solutions were obtained and at the optimal PVP concentration (5%), sufficiently small size and narrow size distributions were obtained from both sodium sulfide and thioacetamide sulfur sources. Finally, the sulfur source directly influences the reaction mechanism and the final particle morphology, as well as the average size.


Assuntos
Nanopartículas Metálicas/química , Micro-Ondas , Povidona/química , Sulfetos/química , Compostos de Zinco/química , Tamanho da Partícula , Tioacetamida/química
18.
Molecules ; 17(12): 14067-90, 2012 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-23192185

RESUMO

Fluorescence, the absorption and re-emission of photons with longer wavelengths, is one of those amazing phenomena of Nature. Its discovery and utilization had, and still has, a major impact on biological and biomedical research, since it enables researchers not just to visualize normal physiological processes with high temporal and spatial resolution, to detect multiple signals concomitantly, to track single molecules in vivo, to replace radioactive assays when possible, but also to shed light on many pathobiological processes underpinning disease states, which would otherwise not be possible. Compounds that exhibit fluorescence are commonly called fluorochromes or fluorophores and one of these fluorescent molecules in particular has significantly enabled life science research to gain new insights in virtually all its sub-disciplines: Green Fluorescent Protein. Because fluorescent proteins are synthesized in vivo, integration of fluorescent detection methods into the biological system via genetic techniques now became feasible. Currently fluorescent proteins are available that virtually span the whole electromagnetic spectrum. Concomitantly, fluorescence imaging techniques were developed, and often progress in one field fueled innovation in the other. Impressively, the properties of fluorescence were utilized to develop new assays and imaging modalities, ranging from energy transfer to image molecular interactions to imaging beyond the diffraction limit with super-resolution microscopy. Here, an overview is provided of recent developments in both fluorescence imaging and fluorochrome engineering, which together constitute the "fluorescence toolbox" in life science research.


Assuntos
Fluorescência , Corantes Fluorescentes/química , Proteínas de Fluorescência Verde , Microscopia de Fluorescência , Pesquisa Biomédica , Corantes/química , Diagnóstico por Imagem , Proteínas de Fluorescência Verde/química , Humanos , Luminescência , Fótons
19.
Molecules ; 17(4): 4047-132, 2012 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-22469598

RESUMO

Fluorescence microscopy provides an efficient and unique approach to study fixed and living cells because of its versatility, specificity, and high sensitivity. Fluorescence microscopes can both detect the fluorescence emitted from labeled molecules in biological samples as images or photometric data from which intensities and emission spectra can be deduced. By exploiting the characteristics of fluorescence, various techniques have been developed that enable the visualization and analysis of complex dynamic events in cells, organelles, and sub-organelle components within the biological specimen. The techniques described here are fluorescence recovery after photobleaching (FRAP), the related fluorescence loss in photobleaching (FLIP), fluorescence localization after photobleaching (FLAP), Förster or fluorescence resonance energy transfer (FRET) and the different ways how to measure FRET, such as acceptor bleaching, sensitized emission, polarization anisotropy, and fluorescence lifetime imaging microscopy (FLIM). First, a brief introduction into the mechanisms underlying fluorescence as a physical phenomenon and fluorescence, confocal, and multiphoton microscopy is given. Subsequently, these advanced microscopy techniques are introduced in more detail, with a description of how these techniques are performed, what needs to be considered, and what practical advantages they can bring to cell biological research.


Assuntos
Microscopia de Fluorescência/métodos , Animais , Recuperação de Fluorescência Após Fotodegradação , Transferência Ressonante de Energia de Fluorescência , Humanos , Microscopia de Fluorescência/instrumentação , Microscopia de Fluorescência por Excitação Multifotônica
20.
Int J Mol Sci ; 12(12): 9031-56, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-22272118

RESUMO

The aim of this work was to investigate the immunomodulatory activities of Rubus coreanus Miquel extract-loaded gelatin nanoparticles. The mean size of the produced nanoparticles was 143 ± 18 nm with a bandwidth of 76 nm in the size distribution and a maximum size of ~200 nm, which allows effective nanoparticle uptake by cells. Confocal imaging confirmed this, since the nanoparticles were internalized within 30 min and heterogeneously distributed throughout the cell. Zeta-potential measurements showed that from pH = 5 onwards, the nanoparticles were highly negatively charged, which prevents agglomeration to clusters by electrostatic repulsion. This was confirmed by TEM imaging, which showed a well dispersed colloidal solution. The encapsulation efficiency was nearly 60%, which is higher than for other components encapsulated in gelatin nanoparticles. Measurements of immune modulation in immune cells showed a significant effect by the crude extract, which was only topped by the nanoparticles containing the extract. Proliferation of B-, T- and NK cells was notably enhanced by Rubus coreanus-gelatin nanoparticles and in general ~2-3 times higher than control and on average ~2 times higher than ferulic acid. R. coreanus-gelatin nanoparticles induced cytokine secretion (IL-6 and TNF-α) from B- and T-cells on average at a ~2-3 times higher rate compared with the extract and ferulic acid. In vivo immunomodulatory activity in mice fed with R. coreanus-gelatin nanoparticles at 1 mL/g body weight showed a ~5 times higher antibody production compared to control, a ~1.3 times higher production compared to the extract only, and a ~1.6 times higher production compared to ferulic acid. Overall, our results suggest that gelatin nanoparticles represent an excellent transport vehicle for Rubus coreanus extract and extracts from other plants generally used in traditional Asian medicine. Such nanoparticles ensure a high local concentration that results in enhancement of immune cell activities, including proliferation, cytokine secretion, and antibody production.


Assuntos
Fatores Imunológicos/farmacologia , Linfócitos/efeitos dos fármacos , Nanopartículas , Extratos Vegetais/farmacologia , Rubus/química , Animais , Proliferação de Células/efeitos dos fármacos , Gelatina/química , Humanos , Interleucina-6/genética , Interleucina-6/metabolismo , Linfócitos/metabolismo , Camundongos , Camundongos Endogâmicos ICR , Extratos Vegetais/química , Fator de Necrose Tumoral alfa/genética , Fator de Necrose Tumoral alfa/metabolismo
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