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1.
Sci Rep ; 13(1): 3960, 2023 Mar 09.
Artigo em Inglês | MEDLINE | ID: mdl-36894619

RESUMO

In this study, Fe3O4/activated carbon nanocomposite was successfully synthesized for removal of Chromium from aqueous solutions. The Fe3O4 nanoparticles were decorated on vine shoots-derived activated carbon using co-precipitation method. The atomic absorption spectrometer was used to evaluate the removal of Chromium ions by the prepared adsorbent. The effect of various parameters such as adsorbent dose, pH, contact time, reusability, electric field, and initial Chromium concentration were examined to find the optimum conditions. According to the results, the synthesized nanocomposite showed a high ability to remove Chromium at an optimized pH of 3. At optimum conditions, a high removal efficiency of 90% and an excellent adsorption capacity of 305.30 mg/g was obtained. In addition, adsorption isotherms and adsorption kinetics were studied in this research. The results showed that the data are well fitted with the Freundlich isotherm and the adsorption process is spontaneous and follows the pseudo-second-order model.

2.
Reprod Biol ; 22(2): 100635, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35305506

RESUMO

Limited heating and cooling rates have long been recognized as bottlenecks in improving embryo cryopreservation. As a result, efforts to achieve higher heat transfer rates gave rise to milestones like open cryodevices and minimal media loading. A crucial but commonly ignored variable is heat conduction by cryosolutions. The low heat conductivity of the aqueous media surrounding embryos slows down cooling and heating rates of the embryo, imposing the risk of preventable damages. In this study, we introduce a novel thermally conductive cryosolution based on graphene oxide nanoparticles and test its performance against conventional sucrose-based solutions for vitrification of mouse blastocysts. Replacing sucrose with graphene oxide brought about similar re-expansion, hatching, and implantation rates of post-vitrification embryos while also preventing an array of cellular and molecular stresses. Our results showed significantly reduced oxidative stress, characterized by control-level expression of Sod1 and significant downregulation of Sod2 transcription when graphene oxide was used instead of sucrose. This molecular response was in agreement with the reduced level of reactive oxygen species produced in vitrified/warmed embryos using graphene-based solutions. The downstream impacts of this stress reduction manifested in significant downregulation of two major pro-apoptotic genes, Bax and Trp53, down to the same level as fresh embryos. Interestingly, embryos maintained their spherical shape during dehydration in graphene-based solutions and did not "collapse" when shrinking, like in sucrose-based solutions. These results provide new insights into the benefits of thermally conductive cryosolutions and showcase the potential of graphene oxide as a cryoprotectant in embryo vitrification.


Assuntos
Grafite , Vitrificação , Animais , Blastocisto/fisiologia , Criopreservação/métodos , Criopreservação/veterinária , Camundongos , Sacarose/farmacologia , Superóxido Dismutase-1
3.
J Educ Health Promot ; 10: 435, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-35071641

RESUMO

BACKGROUND: Parents act as a role model for children in showing health behaviors. This study investigated factors affecting the preventive behavior in elementary school students' parents based on protection motivation theory (PMT). MATERIALS AND METHODS: This cross-sectional study was conducted in Tehran (Iran) in 2020. Multistage sampling was used to choose 660 elementary school students' parents. The data collection instrument was a multi-sectional questionnaire, including sections on demographic characteristics, PMT constructs, self-reported health, and information sources related to COVID-19. In this study, descriptive statistics (mean and standard deviation) and analytical statistical methods (Pearson correlation and path analysis) were used to analyze the data. The range of Cronbach's alpha of the study instrument varied from 0.71 to 0.97. RESULTS: The results of the current study revealed significant association between all PMT constructs and preventive behaviors. Knowledge from both direct and indirect paths was related to preventive behaviors (B = 0.76). Preventive behaviors had the strongest, direct relationship with age (B = 0.76). Based on the final fitted model, knowledge had the greatest impact on preventive behaviors through indirect and direct routes. CONCLUSION: Knowledge was the most important variable which influenced preventive behavior, and it should be noticed in prevention programs.

4.
Breast Cancer Res Treat ; 184(2): 649-651, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32809180

RESUMO

PURPOSE: RAD51C is known as an ovarian cancer gene; however, its role in breast cancer susceptibility is less clear. As part of a larger study, we assessed the role of germline RAD51C mutations in breast cancer development. METHODS: We studied 387 unselected, BRCA1- and BRCA2-negative, Bahamian breast cancer cases and 653 controls to search for novel genetic associations with breast cancer development. During the first phase of the study, whole exome sequencing was utilized in 96 cases to identify an association between novel genes and breast cancer susceptibility. In the second phase of the study, targeted gene sequencing was utilized in the entirety of the cases and controls to identify an association between novel genetic mutations and breast cancer development. RESULTS: A RAD51C mutation was found in five breast cancer cases and in no control (5/387 versus 0/653; p = 0.007). None of the mutation-positive cases reported a family history of ovarian cancer. CONCLUSIONS: These data support increasing evidence that RAD51C mutations contribute to breast cancer susceptibility, although the impact may vary substantially from country to country.


Assuntos
Neoplasias da Mama , Neoplasias Ovarianas , Neoplasias da Mama/epidemiologia , Neoplasias da Mama/genética , Proteínas de Ligação a DNA , Feminino , Predisposição Genética para Doença , Mutação em Linhagem Germinativa , Humanos , Mutação
5.
Breast Cancer Res Treat ; 178(3): 657-663, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31463769

RESUMO

BACKGROUND: XRCC2 participates in homologous recombination and in DNA repair. XRCC2 has been reported to be a breast cancer susceptibility gene and is now included in several breast cancer susceptibility gene panels. METHODS: We sequenced XRCC2 in 617 Polish women with familial breast cancer and found a founder mutation. We then genotyped 12,617 women with breast cancer and 4599 controls for the XRCC2 founder mutation. RESULTS: We identified a recurrent truncating mutation of XRCC2 (c.96delT, p.Phe32fs) in 3 of 617 patients with familial breast cancer who were sequenced. The c.96delT mutation was then detected in 29 of 12,617 unselected breast cancer cases (0.23%) compared to 11 of 4599 cancer-free women (0.24%) (OR = 0.96; 95% CI 0.48-1.93). The mutation frequency in 1988 women with familial breast cancer was 0.2% (OR = 0.84, 95% CI 0.27-2.65). Breast cancers in XRCC2 mutation carriers and non-carriers were similar with respect to age of diagnosis and clinical characteristics. Loss of the wild-type XRCC2 allele was observed only in one of the eight breast cancers from patients who carried the XRCC2 mutation. No cancer type was more common in first- or second-degree relatives of XRCC2 mutation carriers than in relatives of the non-carriers. CONCLUSION: XRCC2 c.96delT is a protein-truncating founder variant in Poland. There is no evidence that this mutation predisposes to breast cancer (and other cancers). It is premature to consider XRCC2 as a breast cancer-predisposing gene.


Assuntos
Neoplasias da Mama/genética , Proteínas de Ligação a DNA/genética , Adulto , Idoso , Alelos , Neoplasias da Mama/epidemiologia , Neoplasias da Mama/patologia , Feminino , Estudos de Associação Genética , Testes Genéticos , Genótipo , Humanos , Pessoa de Meia-Idade , Mutação , Taxa de Mutação , Polônia/epidemiologia
6.
Hum Mutat ; 40(11): 1968-1984, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31343797

RESUMO

Considering the application of human genome variation databases in precision medicine, population-specific genome projects are continuously being developed. However, the Middle Eastern population is underrepresented in current databases. Accordingly, we established Iranome database (www.iranome.com) by performing whole exome sequencing on 800 individuals from eight major Iranian ethnic groups representing the second largest population of Middle East. We identified 1,575,702 variants of which 308,311 were novel (19.6%). Also, by presenting higher frequency for 37,384 novel or known rare variants, Iranome database can improve the power of molecular diagnosis. Moreover, attainable clinical information makes this database a good resource for classifying pathogenicity of rare variants. Principal components analysis indicated that, apart from Iranian-Baluchs, Iranian-Turkmen, and Iranian-Persian Gulf Islanders, who form their own clusters, rest of the population were genetically linked, forming a super-population. Furthermore, only 0.6% of novel variants showed counterparts in "Greater Middle East Variome Project", emphasizing the value of Iranome at national level by releasing a comprehensive catalog of Iranian genomic variations and also filling another gap in the catalog of human genome variations at international level. We introduce Iranome as a resource which may also be applicable in other countries located in neighboring regions historically called Greater Iran (Persia).


Assuntos
Biologia Computacional/métodos , Bases de Dados Genéticas , Etnicidade/genética , Genoma Humano , Genômica , Navegador , Variação Genética , Genética Populacional , Genômica/métodos , Genótipo , Geografia , Humanos , Irã (Geográfico) , Oriente Médio , Anotação de Sequência Molecular
7.
Int J Cancer ; 145(12): 3311-3320, 2019 12 15.
Artigo em Inglês | MEDLINE | ID: mdl-31173646

RESUMO

To optimize genetic testing, it is necessary to establish the spectrum of breast cancer-predisposing mutations in particular ethnic groups. We studied 1,018 women with a strong family history for breast cancer (families with hereditary breast cancer; HBC) from genetically homogenous population of Poland, which is populated by ethnic Slavs, for mutations in 14 cancer susceptibility genes. Additionally, we compared the frequency of candidate pathogenic variants in breast cancer cases and controls. Germline mutations were detected in 512 of 1,018 probands with breast cancer (50.3%), including BRCA1/2 mutations detected in 420 families and non-BRCA mutations seen in 92 families. Thirteen BRCA1/2 founder mutations represented 84% of all BRCA1/2-positive cases. Seven founder mutations of CHEK2, PALB2, NBN and RECQL represented 73% of all non-BRCA-positive cases. Odds ratios for hereditary breast cancer were 87.6 for BRCA1, 15.4 for PALB2, 7.2 for CHEK2, 2.8 for NBN and 15.8 for RECQL. Odds ratios for XRCC2, BLM and BARD1 were below 1.3. In summary, we found that 20 founder mutations in six genes (BRCA1/2, CHEK2, PALB2, NBN and RECQL) are responsible for 82% of Polish hereditary breast cancer families. A simple test for these 20 mutations will facilitate genetic testing for breast cancer susceptibility in Poland. It may also facilitate genetic testing for breast cancer susceptibility in other Slavic populations and women of Slavic descent worldwide.


Assuntos
Neoplasias da Mama/genética , Mutação em Linhagem Germinativa/genética , Adulto , Idoso , Feminino , Predisposição Genética para Doença/genética , Testes Genéticos/métodos , Humanos , Pessoa de Meia-Idade , Polônia
8.
Clin Genet ; 95(6): 643-660, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30671931

RESUMO

Breast cancer is the most common cancer among women worldwide. Due to its complexity in nature, effective breast cancer treatment can encounter many challenges. Traditional methods of cancer detection such as tissue biopsy are not comprehensive enough to capture the entire genomic landscape of breast tumors. However, with the introduction of novel techniques, the application of liquid biopsy has been enhanced, enabling the improvement of various aspects of breast cancer management including early diagnosis and screening, prediction of prognosis, early detection of relapse, serial sampling and efficient longitudinal monitoring of disease progress and response to treatment. Various components of tumor cells released into the blood circulation can be analyzed in liquid biopsy sampling, some of which include circulating tumor cells (CTCs), circulating tumor DNA (ctDNA), cell-free RNA, tumor-educated platelets and exosomes. These components can be utilized for different purposes. As an example, ctDNA can be sequenced for genetic profiling of the tumors to enhance individualized treatment and longitudinal screening. CTC plasma count analysis or ctDNA detection after curative tumor resection surgery could facilitate early detection of minimal residual disease, aiding in the initiation of adjuvant therapy to prevent recurrence. Furthermore, CTC plasma count can be assessed to determine the stage and prognosis of breast cancer. In this review, we discuss the advantages and limitations of the various components of liquid biopsy used in breast cancer diagnosis and will expand on aspects that require further focus in future research.


Assuntos
Biomarcadores Tumorais/genética , Neoplasias da Mama/diagnóstico , Neoplasias da Mama/genética , Ácidos Nucleicos Livres/genética , DNA Tumoral Circulante/genética , Biópsia Líquida , Células Neoplásicas Circulantes/metabolismo , Plaquetas/metabolismo , Neoplasias da Mama/sangue , Neoplasias da Mama/patologia , Exossomos/genética , Exossomos/metabolismo , Feminino , Genômica , Humanos , Recidiva Local de Neoplasia/prevenção & controle , Medicina de Precisão , Prognóstico
9.
J Environ Biol ; 36(1): 215-20, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26536795

RESUMO

Rose is an ornamental plant which contains one of the world's top cut flowers. Vase life of cut rose flower is short. Extracts of Mentha pulegium and 8-hydroxy quinoline sulphate (8-HQS) were used as two preservative solutions, aiming to extend the vase life of cut rose (Rosa hybrid L.) flowers. Rose flowers were treated with a vase solution containing the extract of M. pulegium, at concentrations of 0, 10, 20 and 30%, in combination with 8-HQS at concentrations of 0, 200, 400 and 600 mg l(-1). Longevity of cut roses flowers was determined on the basis of wilting and chlorophyll retention. Cut roses flowers were kept at room temperature (20 ± 2 degrees C) under normal day light and natural ventilation. The vase life of cut flowers studied was prolonged by all 8-HQS and extract treatments. The best concentration of 8-HQS and extractwere 400 mg l(-1) and 10%, respectively. Our results indicated that the flowers treated with the extract and 8-HQS had longer vase life, higher rate of solution uptake and lower SPAD value (total chlorophyll) compared to the control. Also, cut flowers treated with the extract and 8-HQS had least bacterial colonies. The greatest longevity of vase life by 11.20 and 10.25 days was related to 400 mg I(-1) 8-HQS and 10% of extract, respectively. These treatments improved cut vase life more than the control treatment. The maximum solution uptake (1.85 ml g(-1) f.wt.) and minimum SPAD value (2.19) were calculated in 30% extract along with 200 mg l(-1) 8-HQS, and 200 mg l(-1) 8-HQS, respectively. The lowest number of bacterial colonies (55.75) was obtained in treatment of 600 mg l(-1) 8-HQS. Flower quality of specimens treated with extract and 8-HQS was better than those of the control. The experiments were repeated three times with three replicates and a completely randomized design had been used. The present study concludes that it would be possible to use preservative solutions containing extract of M. pulegium L. and 8-HQS to extend vase life of cut rose (R. hybrida L.) flowers.


Assuntos
Flores/efeitos dos fármacos , Mentha pulegium/química , Oxiquinolina/farmacologia , Extratos Vegetais/farmacologia , Rosa/efeitos dos fármacos , Oxiquinolina/química , Extratos Vegetais/química
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