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2.
Int J Mol Sci ; 24(7)2023 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-37047510

RESUMO

Microbial contamination in the hospital environment is a major concern for public health, since it significantly contributes to the onset of healthcare-associated infections (HAIs), which are further complicated by the alarming level of antimicrobial resistance (AMR) of HAI-associated pathogens. Chemical disinfection to control bioburden has a temporary effect and can favor the selection of resistant pathogens, as observed during the COVID-19 pandemic. Instead, probiotic-based sanitation (probiotic cleaning hygiene system, PCHS) was reported to stably abate pathogens, AMR, and HAIs. PCHS action is not rapid nor specific, being based on competitive exclusion, but the addition of lytic bacteriophages that quickly and specifically kill selected bacteria was shown to improve PCHS effectiveness. This study aimed to investigate the effect of such combined probiotic-phage sanitation (PCHSφ) in two Italian hospitals, targeting staphylococcal contamination. The results showed that PCHSφ could provide a significantly higher removal of staphylococci, including resistant strains, compared with disinfectants (-76%, p < 0.05) and PCHS alone (-50%, p < 0.05). Extraordinary sporadic chlorine disinfection appeared compatible with PCHSφ, while frequent routine chlorine usage inactivated the probiotic/phage components, preventing PCHSφ action. The collected data highlight the potential of a biological sanitation for better control of the infectious risk in healthcare facilities, without worsening pollution and AMR concerns.


Assuntos
Bacteriófagos , COVID-19 , Infecção Hospitalar , Probióticos , Humanos , Saneamento/métodos , Cloro , Pandemias , Infecção Hospitalar/prevenção & controle , Infecção Hospitalar/microbiologia , Staphylococcus , Atenção à Saúde , Probióticos/uso terapêutico
3.
Curr Radiopharm ; 15(2): 104-109, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-33655880

RESUMO

INTRODUCTION: The administration of improperly prepared intravenous fluids might determine healthcare-associated infections. Quality and sterility assurance in radiopharmaceutical manufacturing products must be evaluated by media fill tests that simulate the performance of the aseptic manufacturing procedure. The aim of this study is to show a methodological modification of a specific step of media fill tests, giving an overview of economic and organizational advantages that it might bring. MATERIALS AND METHODS: Media fill tests were conducted to ensure that they reproduce as strictly as possible the routine aseptic production process with all the critical steps described in the internal Standard Operating Procedures. We introduced an innovative modification in step 1: instead of using a completely decayed 99Mo/99mTc generator, we used a99Mo/99mTc generator just before its disposal, eluting it with saline solution aspirated in an empty vacuum vial. RESULTS: A total of 47 production runs were performed, and a total of 799 vials were tested for sterility. Thirteen nuclear medicine technicians were assessed. We found contamination in 1% of the total number of vials analyzed. CONCLUSIONS: The modification proposed shows several advantages: reduction of the costs of the media fill tests, the possibility to manage these without referring to external services, and decreased injuries for technicians who perform the tests.


Assuntos
Infertilidade , Compostos Radiofarmacêuticos , Contaminação de Medicamentos/prevenção & controle , Humanos
5.
J Prev Med Hyg ; 61(4): E628-E635, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33628970

RESUMO

INTRODUCTION: The aim of this study is to describe a proactive surveillance system of food, water and environmental surfaces, in order to avoid Healthcare-Associated Infections (HAIs) from hospital environment. METHODS: It is a retrospective descriptive study. The surveillance system consists of two integrated phases: pre-analytic and post-analytic. The activities are distinguished in ordinary control activities, performed after scheduled and shared surveys, and compliance activities, performed when it is necessary to establish the adequacy of the destination use, for example opening a new ward. RESULTS: A total of 1,470 Samples were collected and 539 Reports were generated across the five-year study period. Water for human consumption procedure: a statistically significant trend was found only in the total number of Samples collected (p < 0.001). Legionella spp. infection water risk procedure: all Samples and Reports, with the exception of Compliance Report Samples, showed a statistically significant trend (p < 0.001). Pseudomonas aeruginosa water risk procedure: only Ordinary Reports and Compliance Report Samples trend were statistically significant (p = 0.002 and p = 0.028 respectively). Effectiveness of surface sanitization procedure: no trend was statistically significant (p < 0.05). Hospital catering and food surfaces procedure: Samples and Reports yearly number was constant, no trend analysis was performed. HAIs prevalence was never over 5% in the hospital under study. CONCLUSIONS: This surveillance system of water, food and environmental surfaces represents an innovative way of approaching hospital safety for patients and personnel because it overcomes the limitations due to a classic approach limited to a laboratory analytic phase only, according to the best available scientific evidence.


Assuntos
Infecção Hospitalar , Higiene , Infecção Hospitalar/epidemiologia , Infecção Hospitalar/prevenção & controle , Hospitais , Humanos , Legionella/isolamento & purificação , Legionelose/prevenção & controle , Infecções por Pseudomonas/prevenção & controle , Pseudomonas aeruginosa/isolamento & purificação , Estudos Retrospectivos , Microbiologia da Água
6.
Mediterr J Hematol Infect Dis ; 11(1): e2019062, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31700587

RESUMO

Building-work activities could cause dust contamination and fungal spores' dissemination. A significant relationship was found between building-work activities and the incidence of invasive aspergillosis, in profoundly immunocompromised patients. Renovation-works activities were carried out by four building sites of the hematology ward in a Teaching Hospital without the interruption of clinical activities. These sites were monitored by environmental sampling to determine the particles and fungi count. Clinical surveillance was made using galactomannan antigen test as a proxy for invasive aspergillosis diagnosis. A definitive diagnosis of IA was confirmed by clinical and radiological features. The galactomannan antigen test showed no significant difference between presence (2,75%) and absence (5,03%) of renovation work activities (p=0,522). During the renovation activities, an increment of IA cases with respect to the control period was not recorded. The particle counts showed higher values of small and big-diameter particles before the renovation works if compared to the end of the activities. It was probably due to the containment measures implemented during and immediately after the final phases of the building site. The Fungi counts showed no significant differences between the phase before and after the renovation activities. Our findings show that is possible to perform renovation work, during clinical activities, by increasing clinical and environmental surveillance.

7.
Ital J Food Saf ; 8(3): 8317, 2019 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-31632933

RESUMO

The human consumption of food animal products is the main topic of an important debate among professionals in this sector: dietologists, dietitians and nutritional biologists. The red meat provides all the essential amino acids, bioavailable iron, zinc, calcium, lipids and B-group vitamins. A valid alternative to beef could be the buffalo meat. Italy is the largest European producer of buffalo meat and derivatives. The high nutritional characteristics of buffalo meat make it suitable to be included in the Mediterranean diet to customize it in relation to the needs and conditions of the population. Polyunsaturated/saturated fatty acids ratio can be influenced by diet, breed and type of breeding, but muscle tissue fat percentage is the main factor in determining a favorable fatty acid composition. This review focuses on the biochemical and nutritional characteristics of the buffalo meat (content of fats, cholesterol, amino acids, vitamins and minerals), explaining their variability depending on the different breeds, and the favorable implications on the human health. These results suggest that buffalo meat can be a healthier alternative to beef, not only for healthy people in particular physiological conditions (i.e. pregnancy), but also for persons at risk for cardiovascular and cerebrovascular diseases, thus achieving the goal of a personalized nutrition.

8.
Sci Total Environ ; 657: 248-253, 2019 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-30543973

RESUMO

The prevention of Legionella colonization of water systems is one of the goals of hospital management. Among chemical disinfection methods, chlorine dioxide (ClO2) has been largely used to control Legionella spp. in water systems. We performed a retrospective study to analyse data deriving from the surveillance plan of the water system in a large academic hospital in Rome (Italy) during the period August 2011 and August 2018. We collected the data deriving from the routine water samples used to monitor Legionella spp. colonization. Data from the water samples collected from 163 selected sampling points (hot water tanks, the return loop and distal outlets) was analysed using a life table analysis in order to investigate the duration of the effectiveness of the ClO2 method in eradicating Legionella spp. The colonization of the water sample by Legionella spp. was considered as the outcome. Our results show that in 81,59% of the sampling points Legionella spp. were never detected at four years of follow up. Chemical and physical characteristics of the water were also compared between the samples which were positive for Legionella spp. and those which were not. No association was found between these factors. The knowledge of the duration over time of the effectiveness of the ClO2 disinfection method could support decision-making processes in the framework of Risk Management activities in hospitals. Future studies could also be conducted in hospitals to compare the long-term cost-effectiveness of different Legionella spp. colonization prevention methods.


Assuntos
Compostos Clorados/farmacologia , Desinfetantes/farmacologia , Desinfecção , Água Potável/microbiologia , Monitoramento Ambiental , Legionella/fisiologia , Óxidos/farmacologia , Abastecimento de Água , Desinfecção/estatística & dados numéricos , Hospitais Universitários , Legionella/efeitos dos fármacos , Estudos Retrospectivos , Cidade de Roma , Microbiologia da Água
9.
J Food Prot ; 81(3): 424-429, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29457919

RESUMO

Foodborne diseases and antibiotic resistance are serious widespread health problems in the contemporary world. In this study, we compared the microbiological quality of ready-to-eat (RTE) foods found in community canteens versus hospital canteens in Rome, Italy, focusing on detection and quantification of Enterobacteriaceae and the antibiotic resistance of these bacteria. Our findings show a remarkable difference in Enterobacteriaceae contamination between RTE foods distributed in community canteens (33.5% of samples) and those distributed in hospital canteens (5.3% of samples). This result highlights greater attention to good manufacturing practices and good hygiene practices by the food operators in hospitals compared with food operators in community canteens. As expected, a higher percentage of cold food samples (70.9%) than of hot food samples (10.8%) were positive for these bacteria. Excluding the intrinsic resistance of each bacterial strain, 92.3% of the isolated strains were resistant to at least one antibiotic, and about half of the isolated strains were classified as multidrug resistant. The prevalence of multidrug-resistant strains was 50% in the community samples and 33.3% in hospital canteens. Our results indicate that approximately 38% of RTE foods provided in community canteens is not compliant with microbiological food safety criteria and could be a special risk for consumers through spread of antibiotic-resistant strains. Hygienic processing and handling of foods is necessary for both hospital and community canteens.


Assuntos
Antibacterianos/farmacologia , Farmacorresistência Bacteriana , Enterobacteriaceae/isolamento & purificação , Microbiologia de Alimentos , Enterobacteriaceae/efeitos dos fármacos , Manipulação de Alimentos/métodos , Hospitais , Humanos , Higiene , Itália , Prevalência
10.
Ig Sanita Pubbl ; 74(5): 407-418, 2018.
Artigo em Italiano | MEDLINE | ID: mdl-30780155

RESUMO

INTRODUCTION: The Hospital Hygiene Unit ensures hospital patient safety, through surveillance and control of environmental conditions of risk. In this context, resident physicians in Hygiene and Preventive Medicine of the Catholic University of the Sacred Heart (UCSC) are required to attend the unit to acquire professional skills, for two months (four weeks in the first year of residency and four weeks in the second year). In the initial phase of the rotation, residents are acquainted with the organization and assigned activities. Ongoing meetings with the tutor take place to verify the progress of activities in which they are involved; verification of acquired skills is performed at the end of the period of attendance. The aim of the study was to evaluate resident doctors' opinions about their training experience, in order to assess the perceived quality and pursue continuous improvement of the training program. MATERIALS AND METHODS: A questionnaire was administered to resident physicians attending the first three years of residency; the survey consisted of 11 multiple choice questions on organization, attendance, training and overall satisfaction and 3 open-ended questions on strengths, weaknesses and proposals for improvement. RESULTS: Fourteen of 15 residents (93.3%) completed the questionnaire: seven were male, five were first-year residents, five were second-year and four were third-year residents. Overall, 78% gave a positive assessment of the quality of training; in particular, 11 of 14 residents reported that the experience was very relevant to their training in Hygiene and Preventive Medicine. Responses regarding the training organization were also mostly positive (75%), as were those regarding attendance (57%) and overall satisfaction (67%). Fifty percent reported difficulties in combining this internship with the other activities planned with their tutor. CONCLUSIONS: Positive opinions prevail in all areas of assessment, although there are some aspects that can be improved, including the possibility to extend the period of attendance. Overall, training activities at the Operative Unit of Hospital Hygiene are appreciated by resident physicians, who consider them an important opportunity for professional growth.


Assuntos
Hospitais de Ensino , Internato e Residência , Médicos , Adulto , Feminino , Humanos , Higiene , Masculino , Médicos/psicologia , Projetos Piloto , Inquéritos e Questionários
11.
Ig Sanita Pubbl ; 74(5): 433-442, 2018.
Artigo em Italiano | MEDLINE | ID: mdl-30780157

RESUMO

The authors present the results of a study whose aim was to assess the hygienic quality of powder and reconstituted milk for early childhood, in a University General Hospital in Rome, Italy. This procedure is an integral part of the systematic verification activities that the hospital Health Management department considers as a priority for patient safety. The absence of contamination in all tested samples confirms the suitability of adopted procedures to ensure a safe product, considering the increased vulnerability of newborns, especially if preterm.


Assuntos
Contaminação de Alimentos/prevenção & controle , Inocuidade dos Alimentos , Fórmulas Infantis , Feminino , Humanos , Higiene , Lactente , Fórmulas Infantis/normas , Recém-Nascido , Itália , Masculino , Cidade de Roma
12.
Ig Sanita Pubbl ; 71(1): 9-20, 2015.
Artigo em Italiano | MEDLINE | ID: mdl-25927648

RESUMO

UNLABELLED: The need to integrate clinical and public health training of medical students is increasingly important. Future physicians need to be able to deal with new, complex and growing public health challenges. MATERIALS AND METHODS: A literature search was performed through Pubmed to identify the conceptual reference framework. Meetings were carried out to identify the most appropriate modalities and priorities required for drafting the project, to identify the skills to be acquired by students, to decide on teaching formats and methods to assess student learning, to draw up the teaching schedule, to define the statistical methods to be used to assess student satisfaction, and to perform the statistical analysis of results. Training in hospital hygiene and environmental safety was carried out through presentation of a relevant case. After being divided into groups the students attended the three units (Environmental Microbiology, Environmental Xenobiotics, Genetic Epidemiology and Molecular Biology) of the Hygiene Section of a Public Health Institute. Training in Organization and Health Programming involved presentation of a set of indicators for the definition of objectives and assessment of health systems or services. RESULTS: The literature search led to the identification of the relevant literature. With regard to student satisfaction, 96% of those who replied to the questionnaire gave an overall positive review of the training course (at least 3 on a scale from 1 to 5). CONCLUSIONS: the overall high level of student satisfaction suggests that the proposed model may be exportable. Further developments will be the assessment of trends regarding functioning of the organizational model and perceived teaching quality.


Assuntos
Educação Médica , Saúde Pública/educação , Itália , Projetos Piloto
13.
Genome Biol ; 16: 5, 2015 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-25582055

RESUMO

BACKGROUND: ADAR enzymes convert adenosines to inosines within double-stranded RNAs, including microRNA (miRNA) precursors, with important consequences on miRNA retargeting and expression. ADAR2 activity is impaired in glioblastoma and its rescue has anti-tumoral effects. However, how ADAR2 activity may impact the miRNome and the progression of glioblastoma is not known. RESULTS: By integrating deep-sequencing and array approaches with bioinformatics analyses and molecular studies, we show that ADAR2 is essential to edit a small number of mature miRNAs and to significantly modulate the expression of about 90 miRNAs in glioblastoma cells. Specifically, the rescue of ADAR2 activity in cancer cells recovers the edited miRNA population lost in glioblastoma cell lines and tissues, and rebalances expression of onco-miRNAs and tumor suppressor miRNAs to the levels observed in normal human brain. We report that the major effect of ADAR2 is to reduce the expression of a large number of miRNAs, most of which act as onco-miRNAs. ADAR2 can edit miR-222/221 and miR-21 precursors and decrease the expression of the corresponding mature onco-miRNAs in vivo and in vitro, with important effects on cell proliferation and migration. CONCLUSIONS: Our findings disclose an additional layer of complexity in miRNome regulation and provide information to better understand the impact of ADAR2 editing enzyme in glioblastoma. We propose that ADAR2 is a key factor for maintaining edited-miRNA population and balancing the expression of several essential miRNAs involved in cancer.


Assuntos
Adenosina Desaminase/metabolismo , Neoplasias Encefálicas/genética , Regulação Neoplásica da Expressão Gênica , Glioblastoma/enzimologia , Glioblastoma/genética , MicroRNAs/genética , Edição de RNA/genética , Proteínas de Ligação a RNA/metabolismo , Adolescente , Animais , Encéfalo/enzimologia , Neoplasias Encefálicas/enzimologia , Neoplasias Encefálicas/patologia , Linhagem Celular Tumoral , Movimento Celular , Proliferação de Células , Regulação para Baixo/genética , Perfilação da Expressão Gênica , Inativação Gênica , Glioblastoma/patologia , Células HEK293 , Humanos , Camundongos , MicroRNAs/metabolismo , Modelos Biológicos
14.
Ig Sanita Pubbl ; 71(6): 569-76, 2015.
Artigo em Italiano | MEDLINE | ID: mdl-26847270

RESUMO

The aims of this study were to identify the best threshold value for the real-time PCR method in detecting the presence of Legionella pneumophila in water samples, and to evaluate the prognostic significance of negative results obtained with the molecular method. From 2011 to 2014, 77 water samples were collected from hospital wards of a large University teaching hospital in Rome (Italy) and screened for L.pneumophila by the standard culture method and by real-time PCR. The high sensitivity and negative predictive value of real-time PCR make this method suitable as a quick screening tool to exclude the presence of L. pneumophila in water samples in the hospital setting.


Assuntos
Técnicas Bacteriológicas , Legionella pneumophila/isolamento & purificação , Reação em Cadeia da Polimerase em Tempo Real , Microbiologia da Água , Hospitais de Ensino , Hospitais Universitários , Cidade de Roma
15.
Sci Total Environ ; 499: 47-54, 2014 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-25173861

RESUMO

This study provides a detailed description of the distribution of non-fermentative gram-negative bacteria (NFGNB) collected in water sources (tap water and water used for haemodialysis and bronchoscope flushing) from different wards of a tertiary care hospital. The aim is to identify risk practices for patients or to alert clinicians to the possible contamination of environment and medical devices. The resistance profile of NFGNB environmental isolates has shown that more than half (55.56%) of the strains isolated were resistant to one or more antibiotics tested in different antimicrobial categories. In particular, 38.89% of these strains were multidrug resistant (MDR) and 16.67% were extensively drug resistant (XDR). The most prevalent bacterial species recovered in water samples were Pseudomonas aeruginosa, Pseudomonas fluorescens, Ralstonia pickettii and Stenotrophomonas maltophilia. Analysis of antibiotic resistance rates has shown remarkable differences between Pseudomonadaceae (P. aeruginosa and P. fluorescens) and emerging pathogens, such as S. maltophilia and R. pickettii. Multidrug resistance can be relatively common among nosocomial isolates of P. aeruginosa, which represent the large majority of clinical isolates; moreover, our findings highlight that the emergent antibiotic resistant opportunistic pathogens, such as R. pickettii and S. maltophilia, isolated from hospital environments could be potentially more dangerous than other more known waterborne pathogens, if not subjected to surveillance to direct the decontamination procedures.


Assuntos
Farmacorresistência Bacteriana/genética , Contaminação de Equipamentos/estatística & dados numéricos , Bactérias Gram-Negativas/crescimento & desenvolvimento , Microbiologia da Água , Abastecimento de Água/estatística & dados numéricos , Broncoscópios , Bactérias Gram-Negativas/classificação , Hospitais , Diálise Renal
16.
Ig Sanita Pubbl ; 70(2): 151-69, 2014.
Artigo em Italiano | MEDLINE | ID: mdl-25008222

RESUMO

The purpose of this research is to identify and formalize the Hospital Hygiene Service activities and products, evaluating them in a cost accounting management view. The ultimate aim, is to evaluate the financial adverse events prevention impact, in an Hospital Hygiene Service management. A three step methodology based on affinity grouping activities, was employed. This methodology led us to identify 4 action areas, with 23 related productive processes, and 86 available safety packages. Owing to this new methodology, we was able to implement a systematic evaluation of the furnished services.


Assuntos
Infecção Hospitalar/prevenção & controle , Zeladoria Hospitalar/normas , Higiene , Guias como Assunto , Unidades Hospitalares/normas , Hospitais/normas , Zeladoria Hospitalar/economia , Humanos , Itália
17.
BMC Public Health ; 12: 618, 2012 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-22870945

RESUMO

BACKGROUND: Legionella pneumophila is increasingly recognised as a significant cause of sporadic and epidemic community-acquired and nosocomial pneumonia. Many studies describe the frequency and severity of Legionella spp. contamination in spa pools, natural pools, hotels and ships, but there is no study analysing the environmental monitoring of Legionella on board trains. The aims of the present study were to conduct periodic and precise environmental surveillance of Legionella spp. in water systems and water tanks that supply the toilet systems on trains, to assess the degree of contamination of such structures and to determine the effectiveness of decontamination. METHODS: A comparative pre-post ecological study was conducted from September 2006 to January 2011. A total of 1,245 water samples were collected from plumbing and toilet water tanks on passenger trains. The prevalence proportion of all positive samples was calculated. The unpaired t-test was performed to evaluate statistically significant differences between the mean load values before and after the decontamination procedures; statistical significance was set at p ≤ 0.05. RESULTS: In the pre-decontamination period, 58% of the water samples were positive for Legionella. Only Legionella pneumophila was identified: 55.84% were serogroup 1, 19.03% were serogroups 2-14 and 25.13% contained both serogroups. The mean bacterial load value was 2.14 × 10(3) CFU/L. During the post-decontamination period, 42.75% of water samples were positive for Legionella spp.; 98.76% were positive for Legionella pneumophila: 74.06% contained serogroup 1, 16.32% contained serogroups 2-14 and 9.62% contained both. The mean bacterial load in the post-decontamination period was 1.72 × 10(3) CFU/L. According to the t-test, there was a statistically significant decrease in total bacterial load until approximately one and a half year after beginning the decontamination programme (p = 0.0097). CONCLUSIONS: This study indicates that systematic environmental surveillance could be a useful approach for assessing the risk of exposure to Legionella bacteria, which still represents a public health threat. According to the study results, an environmental surveillance programme, followed by decontamination procedures where necessary, would decrease the total bacterial count, protecting the health of travellers and workers.


Assuntos
Descontaminação , Monitoramento Ambiental , Legionella pneumophila/isolamento & purificação , Banheiros , Meios de Transporte , Microbiologia da Água , Contagem de Colônia Microbiana/estatística & dados numéricos , Humanos , Itália , Doença dos Legionários/prevenção & controle , Avaliação de Programas e Projetos de Saúde
18.
Radiat Res ; 175(5): 535-46, 2011 May.
Artigo em Inglês | MEDLINE | ID: mdl-21361781

RESUMO

MicroRNAs (miRNAs) represent a class of small non-coding RNAs that control gene expression by targeting mRNAs and triggering either repression of translation or RNA degradation. They have been shown to be involved in a variety of biological processes such as development, differentiation and cell cycle control, but little is known about their involvement in the response to irradiation. We showed here that in human umbilical vein endothelial cells (HUVEC) some miRNAs previously shown to have a crucial role in vascular biology are transiently modulated in response to a clinically relevant dose of ionizing radiation. In particular we identified an early transcriptional induction of several members of the microRNA cluster 17-92 and other microRNAs already known to be related to angiogenesis. At the same time we observed a peculiar behavior of the miR-221/222 cluster, suggesting an important role of these microRNAs in HUVEC homeostasis. We observed an increased efficiency in the formation of capillary-like structures in irradiated HUVEC. These results could lead to a new interpretation of the effect of ionizing radiation on endothelial cells and on the response of tumor endothelial bed cells to radiotherapy.


Assuntos
Células Endoteliais/metabolismo , Células Endoteliais/efeitos da radiação , Regulação da Expressão Gênica/efeitos da radiação , MicroRNAs/genética , Neovascularização Fisiológica/genética , Neovascularização Fisiológica/efeitos da radiação , Cordão Umbilical/citologia , Regiões 3' não Traduzidas/genética , Fatores de Transcrição de Zíper de Leucina e Hélice-Alça-Hélix Básicos/genética , Sítios de Ligação , Capilares/citologia , Núcleo Celular/metabolismo , Núcleo Celular/efeitos da radiação , Relação Dose-Resposta à Radiação , Regulação da Expressão Gênica/genética , Células HeLa , Humanos , Transferência Linear de Energia , Estresse Oxidativo/genética , Estresse Oxidativo/efeitos da radiação , Proteínas Proto-Oncogênicas c-myc/metabolismo , Raios X
19.
Arterioscler Thromb Vasc Biol ; 31(4): 898-907, 2011 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21233447

RESUMO

OBJECTIVE: Smad-interacting protein-1 (Sip1/ZEB2) is a transcriptional repressor of the telomerase reverse transcriptase catalytic subunit (Tert) and has recently been identified as a key regulator of embryonic cell fate with a phenotypic effect similar, in our opinion, to that reported for nitric oxide (NO). Remarkably, SIP1/ZEB2 is a known target of the microRNA 200 (miR-200) family. In this light, we postulated that Sip1/ZEB2 and the miR-200 family could play a role during the NO-dependent differentiation of mES. METHODS AND RESULTS: The results of the present study show that Sip1/ZEB2 expression is downregulated during the NO-dependent expression of mesendoderm and early cardiovascular precursor markers, including Flk1 and CXCR4 in mES. Coincidently, members of the miR-200 family, namely miR-429, -200a, -200b, and -200c, were transcriptionally induced in parallel to mouse Tert. This regulation occurred at the level of chromatin. Remarkably, miR-429/miR-200a overexpression or Sip1/ZEB2 knockdown by short hairpin RNA interference elicited a gene expression pattern similar to that of NO regardless of the presence of leukemia inhibitory factor. CONCLUSIONS: These results are the first demonstrating that the miR-200 family and Sip1/ZEB2 transcription factor are regulated by NO, indicating an unprecedented molecular circuitry important for telomerase regulation and early differentiation of mES.


Assuntos
Diferenciação Celular , Células-Tronco Embrionárias/metabolismo , Proteínas de Homeodomínio/metabolismo , MicroRNAs/metabolismo , Óxido Nítrico/metabolismo , Proteínas Repressoras/metabolismo , Transdução de Sinais , Animais , Diferenciação Celular/efeitos dos fármacos , Células Cultivadas , Montagem e Desmontagem da Cromatina , Células-Tronco Embrionárias/efeitos dos fármacos , Regulação da Expressão Gênica no Desenvolvimento , Proteínas de Homeodomínio/genética , Fator Inibidor de Leucemia/metabolismo , Camundongos , Doadores de Óxido Nítrico/farmacologia , Interferência de RNA , RNA Mensageiro/metabolismo , Proteínas Repressoras/genética , Transdução de Sinais/efeitos dos fármacos , Telomerase/metabolismo , Fatores de Tempo , Transcrição Gênica , Transfecção , Homeobox 2 de Ligação a E-box com Dedos de Zinco
20.
Behav Brain Res ; 208(1): 265-9, 2010 Mar 17.
Artigo em Inglês | MEDLINE | ID: mdl-19913057

RESUMO

Several studies have demonstrated that exposure to both acute and chronic aversive stimuli can affect neural activity in different brain areas. In particular it has been shown that stressful events can induce not only short-term changes in neural transmission and gene regulation, but also long-term changes that can lead to structural modification. In this study we investigated, in CD1 mice, the effects of single or repeated exposures to restraint stress (2h for 1 or 5 consecutive days) in the frontal cortex on a crucial class of gene expression regulators, the microRNAs (miRs).First we performed a microarray profiling on RNA extracted from the frontal cortex of mice exposed to acute or repeated restraint stress. The results indicated a prominent increase in the expression levels of different miRs after acute stress while only minor changes were observed after repeated restraint. The Northern blot analysis on selected miRs confirmed an increase after acute restraint for let-7a, miR-9 and miR 26-a/b. Finally, Northern blot analysis of the selected miRs on RNA extracted from the hippocampus of stressed mice demonstrated that such changes were region specific, as no differences were observed in the hippocampus. These data suggest that control of mRNA translation through miRs is an additional mechanism by which stressful events regulates protein expression in the frontal cortex.


Assuntos
Regulação da Expressão Gênica/fisiologia , MicroRNAs/metabolismo , Estresse Psicológico/metabolismo , Animais , Perfilação da Expressão Gênica/métodos , Hipocampo/metabolismo , Masculino , Camundongos , MicroRNAs/classificação , MicroRNAs/genética , Análise de Sequência com Séries de Oligonucleotídeos/métodos , Estresse Psicológico/patologia , Fatores de Tempo
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