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1.
Braz J Med Biol Res ; 54(7): e10520, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34008753

RESUMO

Ischemia-reperfusion injury (IRI) has brought attention to flap failure in reconstructive surgery. To improve the prognosis of skin transplantation, we performed experimental IRI by surgical obstruction of blood flow and used sodium ferulate (SF) to prevent IRI in rats. After SF treatment, the morphological and histological changes of the skin flaps were observed by H&E and Masson's trichrome staining. We also detected the expression levels of COX-1, HO-1, and Ki67 by immunohistochemical and western blot analysis. Moreover, enzyme-linked immunosorbent assay was used to identify the content of tumor necrosis factor (TNF)-α, myeloperoxidase (MPO), malondialdehyde (MDA), and nitric oxide (NO) in peripheral blood and skin tissue. Compared with the model group, SF treatment significantly improved the recovered flap area (%) and promoted collagen synthesis. Cyclooxygenase-2 (COX-2) expression was significantly inhibited by heme oxygenase-1 (HO-1) induction after SF treatment. Furthermore, SF significantly inhibited the levels of TNF-α in peripheral blood, MPO and MDA in the skin tissue, and the increased synthesis of NO. Our results showed the protective effects of SF on IRI after flap transplantation and we believe that the protective effects of SF was closely related to the alleviation of the inflammatory response and the inhibition of the oxidative stress injury.


Assuntos
Estresse Oxidativo , Traumatismo por Reperfusão , Animais , Anti-Inflamatórios/farmacologia , Ácidos Cumáricos/farmacologia , Ratos , Traumatismo por Reperfusão/tratamento farmacológico , Traumatismo por Reperfusão/prevenção & controle
2.
Rev. bras. pesqui. méd. biol ; Braz. j. med. biol. res;54(7): e10520, 2021. graf
Artigo em Inglês | LILACS | ID: biblio-1249321

RESUMO

Ischemia-reperfusion injury (IRI) has brought attention to flap failure in reconstructive surgery. To improve the prognosis of skin transplantation, we performed experimental IRI by surgical obstruction of blood flow and used sodium ferulate (SF) to prevent IRI in rats. After SF treatment, the morphological and histological changes of the skin flaps were observed by H&E and Masson's trichrome staining. We also detected the expression levels of COX-1, HO-1, and Ki67 by immunohistochemical and western blot analysis. Moreover, enzyme-linked immunosorbent assay was used to identify the content of tumor necrosis factor (TNF)-α, myeloperoxidase (MPO), malondialdehyde (MDA), and nitric oxide (NO) in peripheral blood and skin tissue. Compared with the model group, SF treatment significantly improved the recovered flap area (%) and promoted collagen synthesis. Cyclooxygenase-2 (COX-2) expression was significantly inhibited by heme oxygenase-1 (HO-1) induction after SF treatment. Furthermore, SF significantly inhibited the levels of TNF-α in peripheral blood, MPO and MDA in the skin tissue, and the increased synthesis of NO. Our results showed the protective effects of SF on IRI after flap transplantation and we believe that the protective effects of SF was closely related to the alleviation of the inflammatory response and the inhibition of the oxidative stress injury.


Assuntos
Animais , Ratos , Traumatismo por Reperfusão/prevenção & controle , Traumatismo por Reperfusão/tratamento farmacológico , Estresse Oxidativo , Ácidos Cumáricos/farmacologia , Anti-Inflamatórios/farmacologia
3.
Phys Rev Lett ; 124(3): 030601, 2020 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-32031824

RESUMO

When a qubit or spin interacts with others under a many-body Hamiltonian, the information it contains progressively scrambles. Here, nuclear spins of an adamantane crystal are used as a quantum simulator to monitor such dynamics through out-of-time-order correlators, while a Loschmidt echo (LE) asses how weak perturbations degrade the information encoded in these increasingly complex states. Both observables involve the implementation of a time-reversal procedure which, in practice, involves inverting the sign of the effective Hamiltonian. Our protocols use periodic radio frequency pulses to modulate the natural dipolar interaction implementing a Hamiltonian that can be scaled down at will. Meanwhile, experimental errors and strength of perturbative terms remain constant and can be quantified through the LE. For each scaling factor, information spreading occurs with a timescale, T_{2}, inversely proportional to the local second moment of the Hamiltonian. We find that, when the reversible interactions dominate over the perturbations, the information scrambled among up to 10^{2} spins can still be recovered. However, we find that the LE decay rate cannot become smaller than a critical value 1/T_{3}≈(0.15±0.02)/T_{2}, which only depends on the interactions themselves, and not on the perturbations. This result shows the emergence of a regime of intrinsic irreversibility in accordance to a central hypothesis of irreversibility, hinted from previous experiments.

4.
Genet Mol Res ; 15(2)2016 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-27323177

RESUMO

Two single nucleotide polymorphisms (SNPs; TaqI and ApaI) in the vitamin D receptor (VDR) gene have been identified as risk factors for the progression of end-stage renal disease (ESRD). The purpose of our study was to confirm the reported association of these two SNPs with ESRD risk and progression of renal osteodystrophy in a Chinese Han population. A total of 452 ESRD patients and 904 matched-pair controls (based on age, gender, and body mass index) were included. Identification of VDR gene polymorphisms was performed using the polymerase chain reaction-restriction fragment length polymorphism method with TaqI and ApaI restriction enzymes. There was no association of the TaqI polymorphism with ESRD risk. However, significant associations were seen between ApaI (rs7975232) polymorphism and ESRD risk in the heterozygote model (AC/ AA; P = 0.002; OR = 1.4, 95%CI = 1.14-1.83), homozygote model (CC/AA; P = 0.007; OR = 1.8, 95%CI = 1.17-2.85) genotypes for rs7975232, allelic model (P < 0.001; OR = 1.4, 95%CI = 1.15-1.64), dominant model (P = 0.001; OR = 1.5, 95%CI = 1.19-1.87), and recessive model (P = 0.046; OR = 0.6, 95%CI = 0.42-1.00) between cases and healthy controls Moreover, we found a significant correlation between the genotype and allele distribution of ApaI and intact parathyroid hormone (iPTH) levels, where allele C carriers have increased iPTH levels. The ApaI polymorphism in the VDR gene appears to be a susceptibility locus for ESRD in Chinese individuals, and allele C carriers may have an increased risk of high-turnover renal osteodystrophy.


Assuntos
Distúrbio Mineral e Ósseo na Doença Renal Crônica/genética , Receptores de Calcitriol/genética , Adulto , Idoso , Alelos , Povo Asiático/genética , Estudos de Casos e Controles , China , Distúrbio Mineral e Ósseo na Doença Renal Crônica/metabolismo , Feminino , Frequência do Gene , Estudos de Associação Genética , Predisposição Genética para Doença , Humanos , Falência Renal Crônica/genética , Falência Renal Crônica/metabolismo , Masculino , Pessoa de Meia-Idade , Polimorfismo de Nucleotídeo Único , Fatores de Risco
5.
Genet Mol Res ; 14(1): 1557-65, 2015 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-25867299

RESUMO

Genetic maps are essential tools for quantitative trait locus analysis and marker-assisted selection breeding. In order to select parents that are highly heterozygous for genetic mapping, the heterozygosity (HS) of 24 tea cultivars (Camellia sinensis) was analyzed with 72 simple sequence repeat markers. In total, 359 alleles were obtained with an average of 4.99 per marker. The HS varied greatly from 37.5 to 71.0% with an average of 51.3%. On average, tea cultivars from Fujian Province showed a higher level of heterozygosity (59.8%) than those from Zhejiang (48.5%) and Yunnan (44.5%), and the 12 national tea cultivars were generally more heterozygous than the 12 provincial cultivars. Unweighted pair-group analysis using the arithmetic average grouping divided the 24 cultivars into 2 groups that are consistent with the morphological classification. All dual combinations of the 24 cultivars were studied to calculate the percentage of mappable markers when using pseudo-testcross mapping strategy, and results showed that this value also varied greatly from 51.4 to 90.3%. The genetic relationships and HS differences among different cultivars were discussed, and tea cultivars with high HS were recommended as cross parents for genetic mapping programs.


Assuntos
Mapeamento Cromossômico , Marcadores Genéticos , Heterozigoto , Repetições de Microssatélites , Chá/genética , Alelos , China , Análise por Conglomerados , Filogeografia , Melhoramento Vegetal , Polimorfismo Genético , Chá/classificação
6.
Genet Mol Res ; 13(3): 5822-31, 2014 Apr 14.
Artigo em Inglês | MEDLINE | ID: mdl-24782211

RESUMO

Tea is the second most popular non-alcoholic beverage in the world. In recent years, several molecular markers have been used in genetic studies of the tea plant. Yet, only a few single nucleotide polymorphisms (SNPs) have been reported. Here, we identified 818 putative SNPs from expressed sequence tag (EST) databases for the tea plant, which produced a frequency of 1 SNP/170 bp. A direct sequencing method was then used to verify 253 putative SNPs in genome DNA of 17 tea varieties. Fifty (20%) candidate and 299 new SNPs were identified. The haplotype polymorphism and nucleotide diversity of these markers ranged from 0 to 0.960 and 0 to 1.797%, respectively. Using these SNPs, the 17 varieties were classified into 2 groups by cluster analysis. The results indicate that Camellia sinensis-derived ESTs provide a valuable resource for SNP discovery. Furthermore, the abundance of SNPs in tea varieties is anticipated to generate the development of associated genetic studies, in addition to enhancing tea plant-breeding programs.


Assuntos
Camellia sinensis/genética , Polimorfismo de Nucleotídeo Único , Camellia sinensis/classificação , Análise por Conglomerados , Biologia Computacional , Etiquetas de Sequências Expressas , Marcadores Genéticos , Reprodutibilidade dos Testes
7.
Braz J Med Biol Res ; 40(7): 979-84, 2007 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-17653452

RESUMO

Transitional cell carcinoma (TCC) of the urothelium is often multifocal and subsequent tumors may occur anywhere in the urinary tract after the treatment of a primary carcinoma. Patients initially presenting a bladder cancer are at significant risk of developing metachronous tumors in the upper urinary tract (UUT). We evaluated the prognostic factors of primary invasive bladder cancer that may predict a metachronous UUT TCC after radical cystectomy. The records of 476 patients who underwent radical cystectomy for primary invasive bladder TCC from 1989 to 2001 were reviewed retrospectively. The prognostic factors of UUT TCC were determined by multivariate analysis using the COX proportional hazards regression model. Kaplan-Meier analysis was also used to assess the variable incidence of UUT TCC according to different risk factors. Twenty-two patients (4.6%). developed metachronous UUT TCC. Multiplicity, prostatic urethral involvement by the bladder cancer and the associated carcinoma in situ (CIS) were significant and independent factors affecting the occurrence of metachronous UUT TCC (P = 0.0425, 0.0082, and 0.0006, respectively). These results were supported, to some extent, by analysis of the UUT TCC disease-free rate by the Kaplan-Meier method, whereby patients with prostatic urethral involvement or with associated CIS demonstrated a significantly lower metachronous UUT TCC disease-free rate than patients without prostatic urethral involvement or without associated CIS (log-rank test, P = 0.0116 and 0.0075, respectively). Multiple tumors, prostatic urethral involvement and associated CIS were risk factors for metachronous UUT TCC, a conclusion that may be useful for designing follow-up strategies for primary invasive bladder cancer after radical cystectomy.


Assuntos
Carcinoma de Células de Transição/patologia , Segunda Neoplasia Primária/patologia , Neoplasias da Bexiga Urinária/patologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinoma de Células de Transição/cirurgia , Cistectomia , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Prognóstico , Estudos Retrospectivos , Fatores de Risco , Neoplasias da Bexiga Urinária/cirurgia
8.
Rev. bras. pesqui. méd. biol ; Braz. j. med. biol. res;40(7): 979-984, July 2007. tab, graf
Artigo em Inglês | LILACS | ID: lil-455999

RESUMO

Transitional cell carcinoma (TCC) of the urothelium is often multifocal and subsequent tumors may occur anywhere in the urinary tract after the treatment of a primary carcinoma. Patients initially presenting a bladder cancer are at significant risk of developing metachronous tumors in the upper urinary tract (UUT). We evaluated the prognostic factors of primary invasive bladder cancer that may predict a metachronous UUT TCC after radical cystectomy. The records of 476 patients who underwent radical cystectomy for primary invasive bladder TCC from 1989 to 2001 were reviewed retrospectively. The prognostic factors of UUT TCC were determined by multivariate analysis using the COX proportional hazards regression model. Kaplan-Meier analysis was also used to assess the variable incidence of UUT TCC according to different risk factors. Twenty-two patients (4.6 percent). developed metachronous UUT TCC. Multiplicity, prostatic urethral involvement by the bladder cancer and the associated carcinoma in situ (CIS) were significant and independent factors affecting the occurrence of metachronous UUT TCC (P = 0.0425, 0.0082, and 0.0006, respectively). These results were supported, to some extent, by analysis of the UUT TCC disease-free rate by the Kaplan-Meier method, whereby patients with prostatic urethral involvement or with associated CIS demonstrated a significantly lower metachronous UUT TCC disease-free rate than patients without prostatic urethral involvement or without associated CIS (log-rank test, P = 0.0116 and 0.0075, respectively). Multiple tumors, prostatic urethral involvement and associated CIS were risk factors for metachronous UUT TCC, a conclusion that may be useful for designing follow-up strategies for primary invasive bladder cancer after radical cystectomy.


Assuntos
Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Carcinoma de Células de Transição/patologia , Segunda Neoplasia Primária/patologia , Neoplasias da Bexiga Urinária/patologia , Cistectomia , Carcinoma de Células de Transição/cirurgia , Seguimentos , Estadiamento de Neoplasias , Prognóstico , Estudos Retrospectivos , Fatores de Risco , Neoplasias da Bexiga Urinária/cirurgia
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