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1.
Braz J Biol ; 83: e273843, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37466515

RESUMO

Instead of typical household trash, the heavy metal complexes, organic chemicals, and other poisons produced by huge enterprises threaten water systems across the world. In order to protect our drinking water from pollution, we must keep a close eye on the situation. Nanotechnology, specifically two-dimensional (2D) nanomaterials, is used in certain wastewater treatment systems. Graphene, g-C3N4, MoS2, and MXene are just a few examples of emerging 2D nanomaterials that exhibit an extraordinary ratio of surface (m3), providing material consumption, time consumption, and treatment technique for cleaning and observing water. In this post, we'll talk about the ways in which 2D nanomaterials may be tuned to perform certain functions, namely how they can be used for water management. The following is a quick overview of nanostructured materials and its possible use in water management: Also discussed in length are the applications of 2D nanomaterials in water purification, including pollutant adsorption, filtration, disinfection, and photocatalysis. Fluorescence sensors, colorimetric, electrochemical, and field-effect transistors are only some of the devices being studied for their potential use in monitoring water quality using 2D nanomaterials. Utilizing 2D content has its benefits and pitfalls when used to water management. New developments in this fast-expanding business will boost water treatment quality and accessibility in response to rising awareness of the need of clean, fresh water among future generations.


Assuntos
Nanoestruturas , Purificação da Água , Nanoestruturas/química , Nanotecnologia/métodos , Purificação da Água/métodos , Qualidade da Água
2.
Biochim Biophys Acta Mol Basis Dis ; 1869(3): 166621, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36539019

RESUMO

Heme oxygenase-1 (HO-1), which catalyzes heme degradation releasing iron, regulates several processes related to breast cancer. Iron metabolism deregulation is also connected with several tumor processes. However the regulatory relationship between HO-1 and iron proteins in breast cancer remains unclear. Using human breast cancer biopsies, we found that high HO-1 levels significantly correlated with low DMT1 levels. Contrariwise, high HO-1 levels significantly correlated with high ZIP14 and prohepcidin expression, as well as hemosiderin storage. At mRNA level, we found that high HO-1 expression significantly correlated with low DMT1 expression but high ZIP14, L-ferritin and hepcidin expression. In in vivo experiments in mice with genetic overexpression or pharmacological activation of HO-1, we detected the same expression pattern observed in human biopsies. In in vitro experiments, HO-1 activation induced changes in iron proteins expression leading to an increase of hemosiderin, ROS levels, lipid peroxidation and a decrease of the growth rate. Such low growth rate induced by HO-1 activation was reversed when iron levels or ROS levels were reduced. Our findings demonstrate an important role of HO-1 on iron homeostasis in breast cancer. The changes in iron proteins expression when HO-1 is modulated led to the iron accumulation deregulating the iron cell cycle, and consequently, generating oxidative stress and low viability, all contributing to impair breast cancer progression.


Assuntos
Neoplasias da Mama , Ferro , Camundongos , Animais , Humanos , Feminino , Ferro/metabolismo , Heme Oxigenase-1/genética , Heme Oxigenase-1/metabolismo , Neoplasias da Mama/patologia , Espécies Reativas de Oxigênio/metabolismo , Hemossiderina , Sobrevivência Celular
3.
Braz. j. biol ; 83: e273843, 2023.
Artigo em Inglês | VETINDEX | ID: biblio-1447642

RESUMO

Instead of typical household trash, the heavy metal complexes, organic chemicals, and other poisons produced by huge enterprises threaten water systems across the world. In order to protect our drinking water from pollution, we must keep a close eye on the situation. Nanotechnology, specifically two-dimensional (2D) nanomaterials, is used in certain wastewater treatment systems. Graphene, g-C3N4, MoS2, and MXene are just a few examples of emerging 2D nanomaterials that exhibit an extraordinary ratio of surface (m3), providing material consumption, time consumption, and treatment technique for cleaning and observing water. In this post, we'll talk about the ways in which 2D nanomaterials may be tuned to perform certain functions, namely how they can be used for water management. The following is a quick overview of nanostructured materials and its possible use in water management: Also discussed in length are the applications of 2D nanomaterials in water purification, including pollutant adsorption, filtration, disinfection, and photocatalysis. Fluorescence sensors, colorimetric, electrochemical, and field-effect transistors are only some of the devices being studied for their potential use in monitoring water quality using 2D nanomaterials. Utilizing 2D content has its benefits and pitfalls when used to water management. New developments in this fast-expanding business will boost water treatment quality and accessibility in response to rising awareness of the need of clean, fresh water among future generations.


Em vez do lixo doméstico típico, os complexos de metais pesados, produtos químicos orgânicos e outros venenos produzidos por grandes empresas ameaçam os sistemas de água em todo o mundo. Para proteger nossa água potável da poluição, devemos ficar de olho na situação. A nanotecnologia, especificamente nanomateriais bidimensionais (2D), é usada em certos sistemas de tratamento de águas residuais. Grafeno, g-C3N4, MoS2 e MXene são apenas alguns exemplos de nanomateriais 2D emergentes que exibem uma extraordinária proporção de superfície (m3), proporcionando consumo de material, consumo de tempo e técnica de tratamento para limpeza e observação da água. Neste trabalho, trataremos das maneiras pelas quais os nanomateriais 2D podem ser ajustados para desempenhar determinadas funções, ou seja, como eles podem ser usados para o gerenciamento de água. A seguir, uma breve visão geral dos materiais nanoestruturados e seu possível uso no gerenciamento de água. Serão também discutidas detalhadamente as aplicações de nanomateriais 2D na purificação de água, incluindo adsorção de poluentes, filtração, desinfecção e fotocatálise. Sensores de fluorescência, colorimétricos, eletroquímicos e transistores de efeito de campo são apenas alguns dos dispositivos que estão sendo estudados para uso potencial no monitoramento da qualidade da água usando nanomateriais 2D. A utilização de conteúdo 2D tem seus benefícios e armadilhas quando utilizada para gerenciamento de água. Novos desenvolvimentos neste negócio em rápida expansão visam aumentar a qualidade e a acessibilidade do tratamento de água em resposta à crescente conscientização sobre a necessidade de água limpa e fresca entre as gerações futuras.


Assuntos
Poluição da Água/prevenção & controle , Monitoramento da Água , Purificação da Água , Nanoestruturas
4.
An Acad Bras Cienc ; 91(4): e20180165, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31644640

RESUMO

Arbuscular Mycorrhizae (AM) are mutualistic associations between Arbuscular Mycorrhizal Fungi (AMF) and the roots of many plant species. AMF spores give rise to filaments that develop in the root system of plants and contribute to the absorption of water and some nutrients. This article introduces a semi-automated counting model of AMF spores in slide images based on Artificial Neural Network (ANN). The semi-automated counting of AMF spores facilitates and accelerates the tasks of researchers, who still do the AMF spore counting manually. We built a representative database of spore images, processing images through the Circle Hough Transform (CHT) method and training an ANN to classify patterns automatically. The classification analysis and the performances of the proposed method against the manual method are presented in this paper. The accuracy for the identification of spores by CHT in conjunction to ANN classification in the images was 90%. The results indicate that this method can accurately detect the presence of AMF spores in images as well as count them with a high level of confidence.


Assuntos
Micorrizas/isolamento & purificação , Raízes de Plantas/microbiologia , Microbiologia do Solo , Esporos Fúngicos/isolamento & purificação , Algoritmos , Redes Neurais de Computação
5.
Ultrasound Obstet Gynecol ; 52(4): 530-534, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-29280508

RESUMO

OBJECTIVE: To evaluate whether the freeze-all strategy affects in-vitro fertilization (IVF) outcome in poor ovarian responders (POR) defined according to the Bologna criteria. METHOD: This was a retrospective cohort study of patients undergoing IVF treatment between January 2012 and December 2016 at a single center. A total of 433 POR (as defined by the Bologna criteria) fulfilled criteria and were included in the study; of these, 277 patients underwent fresh embryo transfer (ET) and 156 followed the freeze-all policy. All patients underwent controlled ovarian stimulation (COS) following a gonadotropin-releasing hormone antagonist protocol, and cleavage-stage ET. Main outcome measure was ongoing pregnancy rate. Secondary outcomes included implantation and clinical pregnancy rates. The freeze-all strategy was implemented when the progesterone serum level was > 1.5 ng/mL or the endometrium was < 7 mm on the trigger day, or as per patient preference. Patients with previous failed fresh ET also underwent fresh ET or freeze-all strategy considering the indications mentioned above. RESULTS: Mean maternal age in the freeze-all group was 39.5 ± 3.6 years and in the fresh ET group was 39.7 ± 3.8 years (P = 0.54). Mean number of embryos transferred (nET) was 1.53 ± 0.6 and 1.60 ± 0.6 (P = 0.12) in the freeze-all and fresh ET groups, respectively. Ongoing pregnancy rate did not differ significantly between the freeze-all and fresh ET groups (9.6% vs 10.1%, respectively; relative risk (RR), 0.95; 95% CI, 0.52-1.73), nor did the clinical pregnancy rate (14.1% vs 13.7%, respectively; RR, 1.03; 95% CI, 0.63-1.67). Implantation rate was 9.6% and 9.8% (P = 0.82) in the freeze-all and fresh ET groups, respectively. Logistic regression analysis (including maternal age, antral follicle count, number of retrieved and mature oocytes, nET, and fresh ET vs freeze-all strategy) indicated that maternal age (P < 0.001) and nET (P = 0.039) were the only independent variables associated with ongoing pregnancy rate. CONCLUSIONS: The freeze-all strategy, compared with fresh ET, had no impact on IVF outcomes in POR patients as defined according to the Bologna criteria. Multicenter studies including large numbers of patients should be carried out to confirm the results of this study and reach conclusions about the potential benefits of the freeze-all policy for poor responders. Copyright © 2017 ISUOG. Published by John Wiley & Sons Ltd.


Assuntos
Criopreservação/estatística & dados numéricos , Implantação do Embrião/fisiologia , Transferência Embrionária/métodos , Fertilização in vitro , Ovário/fisiopatologia , Adulto , Feminino , Humanos , Indução da Ovulação , Formulação de Políticas , Gravidez , Taxa de Gravidez , Estudos Retrospectivos , Resultado do Tratamento
6.
Ultrasound Obstet Gynecol ; 51(1): 77-86, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-29055060

RESUMO

OBJECTIVE: To evaluate the effectiveness of gonadotropin-releasing hormone agonist (GnRHa) administration before and/or during cancer chemotherapy for the protection of ovarian reserve in premenopausal women without prior diagnosis of infertility. METHODS: This was a systematic review and meta-analysis of randomized controlled trials (RCTs) comparing administration of GnRHa before and/or during chemotherapy vs chemotherapy alone. Eligible participants were premenopausal women at any stage of cancer, without previous diagnosis of infertility. An electronic database search in MEDLINE, CENTRAL, LILACS and ClinicalTrials.gov was performed. After selecting eligible studies, the relative risk (RR) was assessed for primary ovarian insufficiency (POI)/amenorrhea and for spontaneous pregnancy after completion of treatment. RESULTS: Thirteen RCTs comparing concurrent use of GnRHa and chemotherapy (609 participants) with chemotherapy alone (599 participants) were eligible for meta-analysis. All trials were open-label and patients had been treated for breast cancer (n = 1099) or lymphoma (n = 109). GnRHa had a significant benefit on the risk of POI/amenorrhea (RR, 0.60; 95% CI, 0.45-0.79), which persisted in subgroup analysis for breast cancer (RR, 0.57; 95% CI, 0.43-0.77) but not for lymphoma patients (RR, 0.70; 95% CI, 0.20-2.47). The rate of spontaneous pregnancy after completion of treatment was higher in women receiving GnRHa plus chemotherapy compared with those receiving chemotherapy alone (RR, 1.43; 95% CI, 1.01-2.02). Overall, the quality of evidence was low due to the unclear risk of bias, short follow-up and lack of objective assessment of ovarian function and reserve. CONCLUSIONS: Evidence, albeit of low quality, supports the use of GnRHa before and/or during chemotherapy to reduce the risk of POI and increase the probability of spontaneous pregnancy in the short term. Further high quality RCTs with more accurate assessment of ovarian reserve are needed to support definitive recommendations for clinical practice. Copyright © 2017 ISUOG. Published by John Wiley & Sons Ltd.


Assuntos
Antineoplásicos/efeitos adversos , Neoplasias da Mama/tratamento farmacológico , Quimioterapia Adjuvante/efeitos adversos , Preservação da Fertilidade , Hormônio Liberador de Gonadotropina/agonistas , Infertilidade Feminina/prevenção & controle , Reserva Ovariana/efeitos dos fármacos , Insuficiência Ovariana Primária/prevenção & controle , Feminino , Preservação da Fertilidade/métodos , Humanos , Reserva Ovariana/fisiologia , Gravidez , Insuficiência Ovariana Primária/induzido quimicamente , Ensaios Clínicos Controlados Aleatórios como Assunto , Resultado do Tratamento
7.
Andrologia ; 48(3): 252-6, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25998234

RESUMO

Intracytoplasmic sperm injection (ICSI) may be performed with testicular frozen-thawed spermatozoa in patients with nonobstructive azoospermia (NOA). Sperm retrieval can be performed in advance of oocyte aspiration, as it may avoid the possibility of no recovery of spermatozoa on the day of oocyte pickup. There are few studies available in the literature concerning the use of frozen-thawed spermatozoa obtained from testicular sperm aspiration (TESA). To evaluate the effects and the outcomes of ICSI with frozen-thawed spermatozoa obtained by TESA, we performed a retrospective analysis of 43 ICSI cycles using frozen-thawed TESA. We obtained acceptable results with a fertilisation rate of 67.9%, an implantation rate (IR) of 17.1%, and clinical and ongoing pregnancy rates of 41.9% and 37.2% respectively. The results of this study suggest that performing ICSI using cryopreserved frozen-thawed testicular spermatozoa with TESA as a first option is a viable, safe, economic and effective method for patients with NOA.


Assuntos
Implantação do Embrião/fisiologia , Preservação do Sêmen/métodos , Injeções de Esperma Intracitoplásmicas/métodos , Recuperação Espermática , Adulto , Azoospermia/fisiopatologia , Criopreservação , Feminino , Humanos , Masculino , Gravidez , Taxa de Gravidez , Estudos Retrospectivos
8.
Breast Cancer Res Treat ; 155(1): 13-23, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26610810

RESUMO

BRCAness breast tumors represent a group of sporadic tumors characterized by a reduction in BRCA1 gene expression. As BRCA1 is involved in double-strand breaks (DSBs) repair, dysfunctional BRCA pathway could make a tumor sensitive to DNA damaging drugs (e.g., platinum agents). Thus, accurately identifying BRCAness could contribute to therapeutic decision making in patients harboring these tumors. The purpose of this study was to identify if BRCAness tumors present a characteristic methylation profile and/or were related to specific clinico-pathological features. BRCAness was measured by MLPA in 63 breast tumors; methylation status of 98 CpG sites within 84 cancer-related genes was analyzed by MS-MLPA. Protein and mRNA expressions of the selected genes were measured by quantitative real-time PCR and Western Blot. BRCAness was associated with younger age, higher nuclear pleomorphism, and triple-negative (TN) status. Epigenetically, we found that the strongest predictors for BRCAness tumors were the methylations of MLH1 and PAX5 plus the unmethylations of CCND2 and ID4. We determined that ID4 unmethylation correlated with the expression levels of both its mRNA and protein. We observed an inverse relation between the expressions of ID4 and BRCA1. To the best of our knowledge, this is the first report suggesting an epigenetic regulation of ID4 in BRCAness tumors. Our findings give new information of BRCAness etiology and encourage future studies on potential drug targets for BRCAness breast tumors.


Assuntos
Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Epigênese Genética , Regulação Neoplásica da Expressão Gênica , Genes BRCA1 , Genes BRCA2 , Proteínas Inibidoras de Diferenciação/genética , Fenótipo , Adulto , Biomarcadores Tumorais , Neoplasias da Mama/metabolismo , Carcinoma Ductal de Mama/genética , Carcinoma Ductal de Mama/patologia , Ilhas de CpG , Metilação de DNA , Metilases de Modificação do DNA/genética , Metilases de Modificação do DNA/metabolismo , Enzimas Reparadoras do DNA/genética , Enzimas Reparadoras do DNA/metabolismo , Epigenômica/métodos , Feminino , Amplificação de Genes , Humanos , Proteínas Inibidoras de Diferenciação/metabolismo , Pessoa de Meia-Idade , Gradação de Tumores , Estadiamento de Neoplasias , Proteínas Supressoras de Tumor/genética , Proteínas Supressoras de Tumor/metabolismo , Adulto Jovem
9.
Andrologia ; 47(4): 482-5, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-24846759

RESUMO

Testicular germ cell tumours (TGCT) represent 1%-1.5% of all male neoplasms, and they have the highest prevalence among men between 15 and 35 years old. Synchronous bilateral disease is a rare presentation, and the ratio of metachronous to synchronous bilateral disease is about 4 : 1. Several studies have suggested a correlation between male infertility and testicular cancer, with a 20-fold increase in the incidence of testicular cancer in infertile patients compared with the general population. At the time of diagnosis, 50%-75% of patients with unilateral TGCT present with subfertility; almost 13% of the patients are azoospermic before treatment, and up to two-thirds of patients become azoospermic following adjuvant cancer therapies. Therefore, fertility preservation should be considered in all oncological treatments. The only available option to preserve the reproductive potential in azoospermic patients with testicular cancer is to perform an onco-testicular sperm extraction (onco-TESE) before cancer treatment. In this paper, we describe a rare case of a patient with synchronous bilateral testicular cancer and azoospermia who was submitted to onco-TESE, sperm cryopreservation, and which was followed by the delivery of a healthy baby after intracytoplasmic sperm injection (ICSI), emphasising the importance of fertility preservation in oncology patients.


Assuntos
Azoospermia/patologia , Preservação da Fertilidade , Infertilidade Masculina/etiologia , Neoplasias Embrionárias de Células Germinativas/patologia , Espermatozoides/patologia , Neoplasias Testiculares/patologia , Adulto , Azoospermia/complicações , Feminino , Humanos , Infertilidade Masculina/patologia , Masculino , Neoplasias Embrionárias de Células Germinativas/complicações , Gravidez , Resultado da Gravidez , Recuperação Espermática , Neoplasias Testiculares/complicações
10.
Case Rep Gastrointest Med ; 2014: 371638, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25544907

RESUMO

Leiomyomas constitute 2.5% of all resected neoplasms of the stomach. They are usually asymptomatic, but may present mucosal ulceration. Aberrant DNA methylation is a well-defined epigenetic change in human neoplasms; however, gene-acquired methylation may not necessarily be related with a malignant phenotype. In this report we analyzed in a gastric leiomyoma, the methylation status of 84 CpGI in tumor suppressor and DNA repair genes. We analyzed the tumor center (TC) and tumor periphery (TP) separately. We found aberrant methylation in 2/84 CpGI in the TC portion, that is, MLH1 and MSH3, and 5/84 CpGI in the TP, that is, MLH1, MSH3, APC, MSH6, and MGMT. The gene with the highest methylation percentage in the TC and TP was MLH1. Given that MLH1 methylation has been associated with microsatellite instability, we analyzed the status of the microsatellite Bat-26. We found that neither the TC nor the TP presented instability. The methylation of MLH1, MGMT, and APC has been described in GISTs, but to the best of our knowledge this is the first time that the methylation of these genes has been associated with gastric leiomyoma. Further research should be conducted to identify reliable molecular markers that could differentiate between GISTs and gastric leiomyomas.

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