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1.
J Assist Reprod Genet ; 40(4): 943-951, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36864182

RESUMO

Despite many studies in humans and mice using genome transfer (GT), there are few reports using this technique in oocytes of wild or domestic animals. Therefore, we aimed to establish a GT technique in bovine oocytes using the metaphase plate (MP) and polar body (PB) as the sources of genetic material. In the first experiment, GT was established using MP (GT-MP), and a sperm concentration of 1 × 106 or 0.5 × 106 spermatozoa/ml gave similar fertilization rates. The cleavage rate (50%) and blastocyst rate (13.6%) in the GT-MP group was lower than that of the in vitro production control group (80.2% and 32.6%, respectively). The second experiment evaluated the same parameters using PB instead of MP; the GT-PB group had lower fertilization (82.3% vs. 96.2%) and blastocyst (7.7% vs. 36.8%) rates than the control group. No differences in the amount of mitochondrial DNA (mtDNA) were observed between groups. Finally, GT-MP was performed using vitrified oocytes (GT-MPV) as a source of genetic material. The cleavage rate of the GT-MPV group (68.4%) was similar to that of the vitrified oocytes (VIT) control group (70.0%) and to that of the control IVP group (81.25%, P < 0.05). The blastocyst rate of GT-MPV (15.7) did not differ neither from the VIT control group (5.0%) nor from the IVP control group (35.7%). The results suggested that the structures reconstructed by the GT-MPV and GT-PB technique develop in embryos even if vitrified oocytes are used.


Assuntos
Fertilização in vitro , Corpos Polares , Humanos , Masculino , Animais , Bovinos , Camundongos , Fertilização in vitro/métodos , Metáfase/genética , Criopreservação/métodos , Sêmen , Oócitos , Blastocisto
2.
Reprod Fertil Dev ; 33(5): 372-380, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33684338

RESUMO

This study evaluated the effects of three maturation systems, namely invitro (MatV) and invivo (MatS) systems, as well as intrafollicular transfer of immature oocytes (IFIOT; MatT), on the accumulation of lipid droplets in bovine oocytes. Lipids were evaluated using confocal microscopy and transmission electron microscopy. The expression of genes related to lipid metabolism, namely acyl-CoA synthetase short chain family member 2 (ACSS2), ELOVL fatty acid elongase 1 (ELOVL1) and fatty acid binding protein 3 (FABP3), was quantified by quantitative polymerase chain reaction. The mean (±s.d.) area occupied by lipids in immature oocytes (13±2%) was similar to those matured invivo (MatS, 16±2%; MatT, 12±2%). However, there was a significant increase in lipids in oocytes in the MatV group (24±2%) compared with all other groups (P<0.001). In the ultrastructural evaluations, MatV oocytes also showed the highest lipid content. The expression of ELOVL1 and FABP3 was similar in the MatS and IFIOT groups. However, transcript levels of ACSS2 were lower in IFIOT than MatV oocytes. These results indicate, for the first time, that oocytes matured by IFIOT are similar to those matured invivo with regard to lipid accumulation, which indicates better quality than those matured invitro.


Assuntos
Bovinos , Técnicas de Maturação in Vitro de Oócitos/veterinária , Metabolismo dos Lipídeos , Oócitos/crescimento & desenvolvimento , Oócitos/metabolismo , Acetato-CoA Ligase/genética , Animais , Proteína 3 Ligante de Ácido Graxo/genética , Elongases de Ácidos Graxos/genética , Feminino , Expressão Gênica , Metabolismo dos Lipídeos/genética , Oócitos/ultraestrutura , Folículo Ovariano/citologia
4.
Pol J Pathol ; 67(2): 136-44, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-27543868

RESUMO

The hedgehog pathway is known to promote proliferation of pancreatic ductal adenocarcinoma (PDA) and has been shown to restrain tumor progression. To understand how hedgehog causes these effects, we sought to carefully examine protein expression of hedgehog signaling components during different tumor stages. Genetically engineered mice, Pdx1-Cre;LSL-KrasG12D and Pdx1-Cre;LSL-KrasG12D;p53lox/+, were utilized to model distinct phases of tumorigenesis, pancreatic intraepithelial neoplasm (PanIN) and PDA. Human pancreatic specimens of intraductal papillary mucinous neoplasm (IPMN) and PDA were also employed. PanIN and IPMN lesions highly express Sonic Hedgehog, at a level that is slightly higher than that observed in PDA. GLI2 protein is also expressed in both PanIN/IPMN and PDA. Although there was no difference in the nuclear staining, the cytoplasmic GLI2 level in PDA was modest in comparison to that in PanIN/IPMN. Hedgehog interacting protein was strongly expressed in the precursors, whereas the level in PDA was significantly attenuated. There were no differences in expression of Patched1 at early and late stages. Finally, a strong correlation between Sonic Hedgehog and GLI2 staining was found in both human and murine pancreatic tumors. The results indicate that the GLI2 protein level could serve as a feasible marker of ligand-dependent hedgehog activation in pancreatic neoplasms.


Assuntos
Biomarcadores Tumorais/análise , Carcinoma Ductal Pancreático/metabolismo , Fatores de Transcrição Kruppel-Like/biossíntese , Neoplasias Pancreáticas/metabolismo , Adenocarcinoma Mucinoso/metabolismo , Adenocarcinoma Mucinoso/patologia , Adenocarcinoma Papilar/metabolismo , Adenocarcinoma Papilar/patologia , Idoso , Idoso de 80 Anos ou mais , Animais , Carcinoma in Situ/metabolismo , Carcinoma in Situ/patologia , Carcinoma Ductal Pancreático/patologia , Modelos Animais de Doenças , Feminino , Proteínas Hedgehog/metabolismo , Humanos , Imuno-Histoquímica , Fatores de Transcrição Kruppel-Like/análise , Ligantes , Masculino , Camundongos , Camundongos Transgênicos , Pessoa de Meia-Idade , Neoplasias Pancreáticas/patologia , Proteína Gli2 com Dedos de Zinco , Neoplasias Pancreáticas
5.
J Fish Biol ; 87(3): 616-33, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26255608

RESUMO

The life history, reproductive ecology and habitat utilization of the Itasenpara (deepbody) bitterling Acheilognathus longipinnis were investigated in a lowland segment of the Moo River in Toyama Prefecture, central Honshu, Japan. Analysis of 1285 individuals revealed that the study population comprised a single size class, an age at maturation of 3 months and a life span of 1 year. On the basis of the growth pattern, the life cycle was divided into two stages: the juvenile stage, characterized by rapid growth, and the adult stage at which growth ceased. Spawning by A. longipinnis was recorded between early September and late October. Female A. longipinnis in the 0+ year age class began to mature when they reached a standard length (LS ) of 56·4 mm. Mature females had a large clutch size (maximum 273 eggs) and deposited highly adhesive and relatively large eggs (2·55 mm(3) ; major axis, 3·12 mm; minor axis, 1·22 mm) via a short ovipositor (mean length, 21·5 mm) into freshwater mussels. The embryos remained in the gill cavities of the freshwater mussels (used as a spawning substratum) and emerged as juveniles (LS , 9 mm). Habitat utilization during spawning was analysed using a generalized linear model. The best-fit model showed that three environmental factors (freshwater mussel availability, water depth and vegetation cover) were important variables for habitat utilization by A. longipinnis. Shallow areas (water depth, 250-330 mm) created for rice paddy management and areas with an abundance of cover were particularly effective for predator avoidance. These results suggest that maintenance of water level fluctuations corresponding with rice cultivation and the abundance of vegetation on the river bank (particularly avoidance of concrete revetments) is essential for conservation of this species under current practices for rice cultivation in Japan.


Assuntos
Cyprinidae/crescimento & desenvolvimento , Ecossistema , Reprodução , Animais , Bivalves , Conservação dos Recursos Naturais , Espécies em Perigo de Extinção , Feminino , Brânquias , Japão , Oryza , Oviposição , Óvulo , Rios
6.
Ned Tijdschr Tandheelkd ; 121(9): 435-42, 2014 Sep.
Artigo em Holandês | MEDLINE | ID: mdl-25296470

RESUMO

Solitary Median Maxillary Central Incisor syndrome is a rare condition (prevalence 1:50,000), with the characteristic dental feature of a solitary central incisor in the maxilla, positioned exactly in the midline. This single incisor is symmetrical and can be present in the deciduous as well as in the permanent dentition. The syndrome can occur as a mild form of the broad holoprosencephaly-spectrum, but can also be associated with other characteristics. The etiology is still largely unknown, but the syndrome is probably based especially on genetic causes. Early recognition of the syndrome is of great importance for establishing the diagnosis, for additional investigation, for possible treatment of associated anomalies and for the correct advice concerning the risk of inheritance of severe congenital birth defects, related to holoprosencephaly. Dentists and orthodontists can play an important role in this regard and should therefore be able to recognise the clinical features of this condition and know how to refer a patient for further diagnostic counselling.


Assuntos
Holoprosencefalia/complicações , Incisivo/anormalidades , Anormalidades Dentárias/etiologia , Anormalidades Múltiplas , Holoprosencefalia/diagnóstico , Humanos , Maxila , Síndrome , Anormalidades Dentárias/genética
7.
Br J Cancer ; 109(8): 2237-47, 2013 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-24045659

RESUMO

BACKGROUND: Molecules that are highly expressed in tumour endothelial cells (TECs) may be candidates for specifically targeting TECs. Using DNA microarray analysis, we found that the lysyl oxidase (LOX) gene was upregulated in TECs compared with its expression in normal endothelial cells (NECs). LOX is an enzyme that enhances invasion and metastasis of tumour cells. However, there are no reports on the function of LOX in isolated TECs. METHODS: TECs and NECs were isolated to investigate LOX function in TECs. LOX inhibition of in vivo tumour growth was also assessed using ß-aminopropionitrile (BAPN). RESULTS: LOX expression was higher in TECs than in NECs. LOX knockdown inhibited cell migration and tube formation by TECs, which was associated with decreased phosphorylation of focal adhesion kinase (Tyr 397). Immunostaining showed high LOX expression in human tumour vessels in vivo. Tumour angiogenesis and micrometastasis were inhibited by BAPN in an in vivo tumour model. CONCLUSION: LOX may be a TEC marker and a possible therapeutic target for novel antiangiogenic therapy.


Assuntos
Neoplasias da Mama/irrigação sanguínea , Neoplasias da Mama/enzimologia , Melanoma/irrigação sanguínea , Melanoma/enzimologia , Proteína-Lisina 6-Oxidase/metabolismo , Animais , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , Células Endoteliais/enzimologia , Células Endoteliais/patologia , Feminino , Técnicas de Silenciamento de Genes , Humanos , Melanoma/patologia , Camundongos , Camundongos Endogâmicos BALB C , Metástase Neoplásica , Neovascularização Patológica/enzimologia , Proteína-Lisina 6-Oxidase/biossíntese , Proteína-Lisina 6-Oxidase/genética
8.
Int J Oral Maxillofac Surg ; 52(7): 753-759, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-36572572

RESUMO

The purpose of this study was to evaluate the clinical outcomes of patients with stage 3 mandibular medication-related osteonecrosis of the jaw (MRONJ) treated using a submental island flap in combination with mylohyoid muscle reconstruction after rim mandibulectomy. The medical records of 12 patients treated between January 2019 and April 2022 were analysed retrospectively. Primary wound healing was assessed as the maintenance of full mucosal coverage without signs of infection at 6 months postoperatively. The follow-up period ranged from 7 to 38 months, with an average of 21.8 months. All 12 patients (100%) experienced primary wound healing, with normal mouth opening and occlusion, and without pathological mandibular fracture or facial aesthetic problems during the follow-up period. Postoperative panoramic images revealed new bone formation in the treated areas of the mandible in four patients. During the follow-up period, one patient continuing bevacizumab and zoledronate administration for the primary cancer developed MRONJ in the same area at 13 months postoperatively and finally died. Hence the total success rate was 91.7%. In summary, for patients with stage 3 mandibular MRONJ treated with rim mandibulectomy, the submental island flap combined with mylohyoid muscle is an effective reconstructive option for wound-healing and possible bone regeneration of denuded bone.


Assuntos
Osteonecrose da Arcada Osseodentária Associada a Difosfonatos , Osteotomia Mandibular , Humanos , Estudos Retrospectivos , Osteonecrose da Arcada Osseodentária Associada a Difosfonatos/diagnóstico por imagem , Osteonecrose da Arcada Osseodentária Associada a Difosfonatos/cirurgia , Estética Dentária , Retalhos Cirúrgicos , Mandíbula/cirurgia , Músculos
9.
Br J Cancer ; 106(6): 1214-23, 2012 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-22374465

RESUMO

BACKGROUND: We isolated tumour endothelial cells (TECs), demonstrated their abnormalities, compared gene expression profiles of TECs and normal endothelial cells (NECs) by microarray analysis and identified several genes upregulated in TECs. We focused on the gene encoding biglycan, a small leucine-rich repeat proteoglycan. No report is available on biglycan expression or function in TECs. METHODS: The NEC and TEC were isolated. We investigated the biglycan expression and function in TECs. Western blotting analysis of biglycan was performed on sera from cancer patients. RESULTS: Biglycan expression levels were higher in TECs than in NECs. Biglycan knockdown inhibited cell migration and caused morphological changes in TECs. Furthermore, immunostaining revealed strong biglycan expression in vivo in human tumour vessels, as in mouse TECs. Biglycan was detected in the sera of cancer patients but was hardly detected in those of healthy volunteers. CONCLUSION: These findings suggested that biglycan is a novel TEC marker and a target for anti-angiogenic therapy.


Assuntos
Biglicano/metabolismo , Biomarcadores Tumorais/metabolismo , Células Endoteliais/metabolismo , Endotélio Vascular/patologia , Animais , Antígenos CD/metabolismo , Comunicação Autócrina , Biglicano/sangue , Biglicano/genética , Biomarcadores Tumorais/sangue , Biomarcadores Tumorais/genética , Carcinoma de Células Renais/sangue , Carcinoma de Células Renais/irrigação sanguínea , Carcinoma de Células Renais/metabolismo , Carcinoma de Células Renais/patologia , Linhagem Celular Tumoral , Movimento Celular , Proliferação de Células , Células Endoteliais/fisiologia , Endotélio Vascular/metabolismo , Técnicas de Silenciamento de Genes , Humanos , Neoplasias Renais/sangue , Neoplasias Renais/irrigação sanguínea , Neoplasias Renais/metabolismo , Neoplasias Renais/patologia , Melanoma/irrigação sanguínea , Melanoma/metabolismo , Melanoma/patologia , Camundongos , Camundongos Nus , Transplante de Neoplasias
10.
Clin Oncol (R Coll Radiol) ; 34(12): e505-e514, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-35654667

RESUMO

AIMS: Although palliative radiotherapy for gastric cancer may improve some symptoms, it may also have a negative impact due to its toxicity. We investigated whether symptoms improved after radiotherapy with adjustment for the Palliative Prognostic Index (PPI) considering that patients with limited survival tend to experience deterioration of symptoms. MATERIALS AND METHODS: This study was an exploratory analysis of the Japanese Radiation Oncology Study Group study (JROSG 17-3). We assessed six symptom scores (nausea, anorexia, fatigue, shortness of breath, pain at the irradiated area and distress) at registration and 2, 4 and 8 weeks thereafter. We tested whether symptoms linearly improved after adjusting for the baseline PPI. Shared parameter models were used to adjust for potential bias in missing data. RESULTS: The present study analysed all 55 patients enrolled in JROSG 17-3. With time from registration as the only explanatory variable in the model, a significant linear decrease was observed in shortness of breath, pain and distress (slopes, -0.26, -0.22 and -0.19, respectively). Given that the interaction terms (i.e. PPI × time) were not significantly associated with symptom scores in any of the six symptoms, only PPI was included as the main effect in the final multivariable models. After adjusting for the PPI, shortness of breath, pain and distress significantly improved (slope, -0.25, -0.19 and -0.17; P < 0.001, 0.002 and 0.047, respectively). An improvement in fatigue and distress was observed only in patients treated with a biologically effective dose ≤14.4 Gy. CONCLUSION: Shortness of breath, pain and distress improved after radiotherapy. Moreover, a higher PPI was significantly associated with higher symptom scores at all time points, including baseline. In contrast, PPI did not seem to influence the improvement of these symptoms. Regardless of the expected survival, patients receiving radiotherapy for gastric cancer can expect an improvement in shortness of breath, pain and distress over 8 weeks. Multiple-fraction radiotherapy might hamper the improvement in fatigue and distress by its toxicity or treatment burden.


Assuntos
Radioterapia (Especialidade) , Neoplasias Gástricas , Humanos , Prognóstico , Neoplasias Gástricas/complicações , Neoplasias Gástricas/radioterapia , Cuidados Paliativos , Fadiga/etiologia , Dor/etiologia , Dor/radioterapia , Dor/diagnóstico , Dispneia/etiologia , Dispneia/radioterapia
11.
Int J Immunopathol Pharmacol ; 24(4): 837-47, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-22230391

RESUMO

Ethyl tertiary-butyl ether (ETBE) is a motor fuel oxygenate used in reformulated gasoline. The current use of ETBE in gasoline or petrol is modest but increasing. To investigate the effects of ETBE on splenocytes, mice were exposed to 0 (control), 500 ppm, 1750 ppm, or 5000 ppm of ETBE by inhalation for 6 h/day for 5 days/wk over a 6- or 13-week period. Splenocytes were harvested from the control and exposed mice, and the following cell phenotypes were quantified by flow cytometry: (1) B cells (PerCP-Cy5.5-CD45R/B220), (2) T cells (PerCP-Cy5-CD3e), (3) T cell subsets (FITC-CD4 and PE-CD8a), (4) natural killer (NK) cells (PE-NK1.1), and (5) macrophages (FITC-CD11b). Body weight and the weight of the spleen were also examined. ETBE-exposure did not affect the weight of the spleen or body weight, while it transiently increased the number of RBC and the Hb concentration. The numbers of splenic CD3+, CD4+, and CD8+ T cells, the percentage of CD4+ T cells and the CD4+/CD8+ T cell ratio in the ETBE-exposed groups were significantly decreased in a dose-dependent manner. However, ETBE exposure did not affect the numbers of splenic NK cells, B cells, or macrophages or the total number of splenocytes. The above findings indicate that ETBE selectively affects the number of splenic T cells in mice.


Assuntos
Poluentes Atmosféricos/toxicidade , Etil-Éteres/toxicidade , Baço/efeitos dos fármacos , Animais , Antígenos CD/análise , Linfócitos B/efeitos dos fármacos , Linfócitos B/imunologia , Peso Corporal/efeitos dos fármacos , Relação Dose-Resposta a Droga , Citometria de Fluxo , Imunofenotipagem/métodos , Exposição por Inalação , Células Matadoras Naturais/efeitos dos fármacos , Células Matadoras Naturais/imunologia , Contagem de Linfócitos , Macrófagos/efeitos dos fármacos , Macrófagos/imunologia , Masculino , Camundongos , Camundongos da Linhagem 129 , Camundongos Endogâmicos C57BL , Tamanho do Órgão/efeitos dos fármacos , Baço/imunologia , Baço/patologia , Linfócitos T/efeitos dos fármacos , Linfócitos T/imunologia , Fatores de Tempo
12.
J Radiat Res ; 62(4): 718-725, 2021 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-33912958

RESUMO

During radiotherapy sessions to treat brain tumors or head-and-neck cancers, some patients experience unusual visual and/or olfactory perceptions. This prospective study sought to answer two questions: (i) what proportion of patients experience these unpleasant sensations?, and (ii) which organs are responsible? Eligible patients had brain or near-orbital tumors treated by helical tomotherapy. All were aged 10 years or older, able to communicate, and interviewed by a radiation oncologist at least once weekly during radiation therapy. If they had experienced such sensations, they were encouraged to join the second phase of the study. The patients were asked to indicate, using a button, when a sensation commenced and ended. The recorded data were collated with the treatment log. Thirty-eight consecutive patients were eligible. Twenty-six experienced visual and 13 olfactory sensations. The radiation doses to the organs related to the visual or olfactory sensations did not differ between patients who reported sensations and those who did not. Seventeen patients were enrolled in the second phase of the study. All 14 with visual sensations reported that the sensations occurred when the X-rays passed at eye level. Olfactory sensations were reported by eight out of nine patients when the X-rays passed through the olfactory epithelium and/or ethmoid sinus level. In conclusion, 68% of patients experienced visual sensations caused by X-rays passing through the level of the eyes, and 34% complained of olfactory sensations. With the exception of one patient, olfactory sensations occurred when the X-rays passed through the levels of the olfactory epithelium and/or ethmoid sinus.


Assuntos
Percepção Olfatória/fisiologia , Especificidade de Órgãos , Radioterapia , Percepção Visual/fisiologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Radiometria , Adulto Jovem
13.
J Exp Med ; 165(6): 1761-6, 1987 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-3585251

RESUMO

P3-X63-Ag8 and X63-Ag8.653 mouse myeloma cells have an absolute requirement for cholesterol for growth under serum-free conditions. This requirement can be satisfied by low density lipoprotein at 2-6 micrograms/ml or by BSA-bound cholesterol at 5-10 micrograms/ml. Cholesterol-independent variants can be selected after prolonged growth in low concentrations of serum.


Assuntos
Colesterol/farmacologia , Mieloma Múltiplo/patologia , Animais , Células Cultivadas , Meios de Cultura , Humanos , Lipoproteínas LDL/farmacologia , Camundongos
14.
Stud Health Technol Inform ; 132: 316-21, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18391312

RESUMO

This paper presents a volume manipulation framework by which surgeons can interactively manipulate soft models like through surgical tools. The framework robustly simulates common surgical manipulations such as grasping, holding, cutting and retraction. We simulate cutting based on FEM formulation by replacing vertices and eliminating elements, without subdividing elements or adding new vertices. The size of stiffness matrix is constant. We also present real-time volume shading methods for deformable modeling. Our algorithms achieved interactive response in volume manipulation. Several surgical approaches and procedures were rehearsed and used for preoperative discussion.


Assuntos
Cuidados Pré-Operatórios/métodos , Procedimentos Cirúrgicos Operatórios , Tato , Interface Usuário-Computador , Humanos , Japão
15.
Toxicol Lett ; 297: 8-18, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30125618

RESUMO

Consumer exposure to cosmetic (personal care) products is mostly by dermal contact, however additional considerations with regards to potential inhalation exposure from some cosmetics, such as sprays and powders, may be needed for a robust and reliable safety assessment. To get a deeper understanding of the exposure to airborne particles and droplets during product application, a team of international experts was founded under the umbrella of the European Association of the Cosmetic Industry "Cosmetics Europe" (CE) in Brussels. This expert team has worked out a pragmatic strategy how small and medium sized enterprises (SMEs), but also relevant authorities, could handle the safety evaluation of cosmetic powder products. Sufficient information on the aerodynamic diameter of sprayed droplets and here specifically of airborne particles is essential in addition to knowing the exposure after typical product application. The current article is focused on the determination of inhalation exposure to solids, and the derivation of safe exposure levels for cosmetic powder products found in the market. The principles described herein are very similar to spray products as published earlier and should be applied in a similar way (Steiling et al., 2014). Prediction models for the best estimate of inhalation exposure, developed with data from computer simulation programs, individual real-time measurements or finally by experience from the market were introduced and applied. Safety assessment approaches for exposure from powder spray products were developed and have been already considered in regulatory guidelines like the EC Cosmetics Regulation.


Assuntos
Qualidade de Produtos para o Consumidor , Cosméticos/efeitos adversos , Pós/efeitos adversos , Aerossóis/efeitos adversos , Animais , Humanos , Exposição por Inalação/efeitos adversos , Tamanho da Partícula , Material Particulado/efeitos adversos
16.
Environ Int ; 114: 77-86, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29499450

RESUMO

A variety of experimental and epidemiological studies lend support to the Developmental Origin of Health and Disease (DOHaD) concept. Yet, the actual mechanisms accounting for mid- and long-term effects of early-life exposures remain unclear. Epigenetic alterations such as changes in DNA methylation, histone modifications and the expression of certain RNAs have been suggested as possible mediators of long-term health effects of environmental stressors. This report captures discussions and conclusions debated during the last Prenatal Programming and Toxicity meeting held in Japan. Its first aim is to propose a number of criteria that are critical to support the primary contribution of epigenetics in DOHaD and intergenerational transmission of environmental stressors effects. The main criteria are the full characterization of the stressors, the actual window of exposure, the target tissue and function, the specificity of the epigenetic changes and the biological plausibility of the linkage between those changes and health outcomes. The second aim is to discuss long-term effects of a number of stressors such as smoking, air pollution and endocrine disruptors in order to identify the arguments supporting the involvement of an epigenetic mechanism. Based on the developed criteria, missing evidence and suggestions for future research will be identified. The third aim is to critically analyze the evidence supporting the involvement of epigenetic mechanisms in intergenerational and transgenerational effects of environmental exposure and to particularly discuss the role of placenta and sperm. While the article is not a systematic review and is not meant to be exhaustive, it critically assesses the contribution of epigenetics in the long-term effects of environmental exposures as well as provides insight for future research.


Assuntos
Exposição Ambiental , Poluentes Ambientais/toxicidade , Epigênese Genética/efeitos dos fármacos , Metilação de DNA/efeitos dos fármacos , Feminino , Humanos , Masculino , Gravidez
17.
Br J Pharmacol ; 150(4): 526-33, 2007 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-17220910

RESUMO

BACKGROUND AND PURPOSE: Mitochondrial aldehyde dehydrogenase (ALDH-2) has been shown to provide a pathway for bioactivation of organic nitrates and to be prone to desensitization in response to highly potent, but not to less potent, nitrates. We therefore sought to support the hypothesis that bioactivation by ALDH-2 critically depends on the number of nitrate groups within the nitrovasodilator. EXPERIMENTAL APPROACH: Nitrates with one (PEMN), two (PEDN; GDN), three (PETriN; glyceryl trinitrate, GTN) and four (pentaerithrityl tetranitrate, PETN) nitrate groups were investigated. Vasodilatory potency was measured in isometric tension studies using isolated aortic segments of wild type (WT) and ALDH-2-/- mice. Activity of the cGMP-dependent kinase-I (reflected by levels of phosphorylated VAsodilator Stimulated Phosphoprotein, P-VASP) was quantified by Western blot analysis, mitochondrial dehydrogenase activity by HPLC. Following incubation of isolated mitochondria with PETN, PETriN-chromophore and PEDN, metabolites were quantified using chemiluminescence nitrogen detection and mass spectrometry. KEY RESULTS: Compared to WT, vasorelaxation in response to PETN, PETriN and GTN was attenuated about 10fold in ALDH-2-/- mice, identical to WT vessels preincubated with inhibitors of ALDH-2. Reduced vasodilator potency correlated with reduced P-VASP formation and diminished biotransformation of the tetranitrate- and trinitrate-compounds. None of these findings were observed for PEDN, GDN and PEMN. CONCLUSIONS AND IMPLICATIONS: Our results support the crucial role of ALDH-2 in bioactivating highly reactive nitrates like GTN, PETN and PETriN. ALDH-2-mediated relaxation by organic nitrates therefore depends mainly on the number of nitrate groups. Less potent nitrates like PEDN, GDN and PEMN are apparently biotransformed by other pathways.


Assuntos
Aldeído Desidrogenase/genética , Nitratos/química , Nitratos/farmacologia , Aldeído-Desidrogenase Mitocondrial , Animais , Western Blotting , Moléculas de Adesão Celular/metabolismo , Proteínas Quinases Dependentes de GMP Cíclico/metabolismo , Contração Isométrica/efeitos dos fármacos , Luminescência , Espectrometria de Massas , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Proteínas dos Microfilamentos/metabolismo , Mitocôndrias Musculares/enzimologia , Nitroglicerina/análogos & derivados , Nitroglicerina/farmacologia , Nitroprussiato/farmacologia , Oxidiazóis/farmacologia , Tetranitrato de Pentaeritritol/farmacologia , Fosfoproteínas/metabolismo , Quinoxalinas/farmacologia , Relação Estrutura-Atividade , Vasodilatadores/farmacologia
18.
Mol Cell Biol ; 21(8): 2838-46, 2001 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-11283262

RESUMO

In response to phenobarbital (PB) and other PB-type inducers, the nuclear receptor CAR translocates to the mouse liver nucleus (T. Kawamoto et al., Mol. Cell. Biol. 19:6318-6322, 1999). To define the translocation mechanism, fluorescent protein-tagged human CAR (hCAR) was expressed in the mouse livers using the in situ DNA injection and gene delivery systems. As in the wild-type hCAR, the truncated receptor lacking the C-terminal 10 residues (i.e., AF2 domain) translocated to the nucleus, indicating that the PB-inducible translocation is AF2 independent. Deletion of the 30 C-terminal residues abolished the receptor translocation, and subsequent site-directed mutagenesis delineated the PB-inducible translocation activity of the receptor to the peptide L313GLL316AEL319. Ala mutations of Leu313, Leu316, or Leu319 abrogated the translocation of CAR in the livers, while those of Leu312 or Leu315 did not affect the nuclear translocation. The leucine-rich peptide dictates the nuclear translocation of hCAR in response to various PB-type inducers and appears to be conserved in the mouse and rat receptors.


Assuntos
Núcleo Celular/metabolismo , Fígado/efeitos dos fármacos , Fígado/metabolismo , Receptores Citoplasmáticos e Nucleares/química , Receptores Citoplasmáticos e Nucleares/metabolismo , Fatores de Transcrição/química , Fatores de Transcrição/metabolismo , Xenobióticos/farmacologia , Sequência de Aminoácidos , Animais , Transporte Biológico Ativo/efeitos dos fármacos , Linhagem Celular , Receptor Constitutivo de Androstano , Proteínas de Fluorescência Verde , Humanos , Proteínas Luminescentes/genética , Proteínas Luminescentes/metabolismo , Camundongos , Dados de Sequência Molecular , Mutagênese Sítio-Dirigida , Fenobarbital/farmacologia , Ratos , Receptores Citoplasmáticos e Nucleares/genética , Proteínas Recombinantes de Fusão/química , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/metabolismo , Deleção de Sequência , Fatores de Transcrição/genética
19.
Mol Cell Biol ; 19(9): 6318-22, 1999 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-10454578

RESUMO

The constitutively active receptor (CAR) transactivates a distal enhancer called the phenobarbital (PB)-responsive enhancer module (PBREM) found in PB-inducible CYP2B genes. CAR dramatically increases its binding to PBREM in livers of PB-treated mice. We have investigated the cellular mechanism of PB-induced increase of CAR binding. Western blot analyses of mouse livers revealed an extensive nuclear accumulation of CAR following PB treatment. Nuclear contents of CAR perfectly correlate with an increase of CAR binding to PBREM. PB-elicited nuclear accumulation of CAR appears to be a general step regulating the induction of CYP2B genes, since treatments with other PB-type inducers result in the same nuclear accumulation of CAR. Both immunoprecipitation and immunohistochemistry studies show cytoplasmic localization of CAR in the livers of nontreated mice, indicating that CAR translocates into nuclei following PB treatment. Nuclear translocation of CAR also occurs in mouse primary hepatocytes but not in hepatocytes treated with the protein phosphatase inhibitor okadaic acid. Thus, the CAR-mediated transactivation of PBREM in vivo becomes PB responsive through an okadaic acid-sensitive nuclear translocation process.


Assuntos
Hidrocarboneto de Aril Hidroxilases , Sistema Enzimático do Citocromo P-450/genética , Fenobarbital/farmacologia , Receptores Citoplasmáticos e Nucleares/metabolismo , Esteroide Hidroxilases , Transativadores/metabolismo , Fatores de Transcrição , Animais , Sequência de Bases , Transporte Biológico Ativo/efeitos dos fármacos , Linhagem Celular , Núcleo Celular/metabolismo , Receptor Constitutivo de Androstano , Família 2 do Citocromo P450 , Primers do DNA/genética , Elementos Facilitadores Genéticos , Regulação Enzimológica da Expressão Gênica , Humanos , Imuno-Histoquímica , Técnicas In Vitro , Fígado/efeitos dos fármacos , Fígado/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos ICR , Ácido Okadáico/farmacologia
20.
Mol Cell Biol ; 8(4): 1816-20, 1988 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-3380099

RESUMO

By using Southern blot analysis, we found that in two cases of human glioblastoma multiforme, cells carried amplified c-erbB genes which bore short deletion mutations within the ligand-binding domain of the epidermal growth factor (EGF) receptor. The products of these mutated c-erbB genes were about 30 kilodalton (kDa) smaller than the normal 170-kDa EGF receptor, and the tumor cell membrane fractions containing the 140-kDa abnormal EGF receptor showed a significant elevation of tyrosine kinase activity without its ligand. In view of the similarity to the activated viral and cellular erbB genes in the avian system, these mutated and overexpressed EGF receptors might play a role in the onset or development of human glioblastoma cells.


Assuntos
Neoplasias Encefálicas/genética , Receptores ErbB/genética , Amplificação de Genes , Genes , Proto-Oncogenes , Animais , Neoplasias Encefálicas/metabolismo , Deleção Cromossômica , Receptores ErbB/metabolismo , Humanos , Camundongos , Camundongos Nus , Mutação , Transplante de Neoplasias , RNA Mensageiro/genética , Transplante Heterólogo , Células Tumorais Cultivadas/metabolismo
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