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1.
Entropy (Basel) ; 24(2)2022 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-35205513

RESUMO

Stator coils of automobiles in operation generate heat and are cooled by coolant poured from above. The flow characteristic of the coolant depends on the coil structure, flow condition, solid-fluid interaction, and fluid property, which has not been clarified due to its complexities. Since straight coils are aligned and layered with an angle at the coolant-touchdown region, the coil structure is simplified to a horizontal square rod array referring to an actual coil size. To obtain the flow and wetting characteristics, two-phase fluid flow simulations are conducted by using the phase-field lattice Boltzmann method. First, the flow onto the single-layered rod array is discussed. The wetting area is affected both by the rod gap and the wettability, which is normalized by the gap and the averaged boundary layer thickness. Then, the flow onto the multi-layered rod arrays is investigated with different rod gaps. The top layer wetting becomes longitudinal due to the reduction of the flow advection by the second layer. The wetting area jumps up at the second layer and increases proportionally to the below layers. These become remarkable at the narrow rod gap case, and finally, the dimensionless wetting area is discussed at each layer.

2.
Phys Rev E ; 103(5-1): 053307, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-34134238

RESUMO

A consistent evaporation model is developed for the conservative Allen-Cahn-based phase-field lattice Boltzmann method that uses an appropriate source term to recover the advection-diffusion equation for the specific humidity. To evaluate the accuracy of the proposed scheme, simulations are conducted of a steady-state one-dimensional Stefan flow for a flat interface and a three-dimensional evaporating sessile droplet on a flat substrate for a curved interface. It is confirmed that the results for the evaporative mass flux of the Stefan flow agree well with those obtained from the analytical solution within a specific humidity range of 0.8 or less at the liquid-gas interface. For the sessile droplet case, the results for the dependence of the contact angle on the evaporative mass flux and its profile show good agreement with those obtained from the model of Hu and Larson [J. Phys. Chem. B 106, 1334 (2002)JPCBFK1520-610610.1021/jp0118322].

4.
J Org Chem ; 86(6): 4859-4866, 2021 03 19.
Artigo em Inglês | MEDLINE | ID: mdl-33667103

RESUMO

Synthesis of (+)-muconin isolated from Rollinia mucosa (Annonaceae) was achieved. Stereoselective construction of a tetrahydrofuran-terahydropyran (THF-THP) ring moiety was performed using diastereoselective oxypalladation in the presence of CuCl2. The cross-coupling reaction of the THF-THP moiety with the γ-lactone portion followed by reduction of the enyne and removal of the protecting groups afforded (+)-muconin.


Assuntos
Annonaceae , Lactonas , Álcoois Graxos , Estereoisomerismo
5.
J Biosci Bioeng ; 123(4): 437-443, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28007420

RESUMO

Pyruvate dehydrogenase complex regulator (PdhR) is a transcriptional regulator that negatively regulates formation of pyruvate dehydrogenase complex (PDHc), NADH dehydrogenase (NDH)-2, and cytochrome bo3 oxidase in Escherichia coli. To investigate the effects of a PdhR defect on glucose metabolism, a pdhR deletion mutant was derived from the wild-type E. coli W1485 strain by λ Red-mediated recombination. While no difference in the fermentation profiles was observed between the two strains under oxygen-sufficient conditions, under oxygen-limited conditions, the growth level of the wild-type strain was significantly decreased with retarded glucose consumption accompanied by by-production of substantial amounts of pyruvic acid and acetic acid. In contrast, the mutant grew and consumed glucose more efficiently than did the wild-type strain with enhanced respiration, little by-production of pyruvic acid, less production yield and rates of acetic acid, thus displaying robust metabolic activity. As expected, increased activities of PDHc and NDH-2 were observed in the mutant. The increased activity of PDHc may explain the loss of pyruvic acid by-production, probably leading to decreased acetic acid formation, and the increased activity of NDH-2 may explain the enhanced respiration. Measurement of the intracellular NAD+/NADH ratio in the mutant revealed more oxidative or more reductive intracellular environments than those in the wild-type strain under oxygen-sufficient and -limited conditions, respectively, suggesting another role of PdhR: maintaining redox balance in E. coli. The overall results demonstrate the biotechnological advantages of pdhR deletion in boosting glucose metabolism and also improve our understanding of the role of PdhR in bacterial physiology.


Assuntos
Escherichia coli/metabolismo , Deleção de Genes , Glucose/metabolismo , Oxigênio/metabolismo , Complexo Piruvato Desidrogenase/metabolismo , Proteínas Repressoras/deficiência , Ácido Acético/metabolismo , Respiração Celular , Grupo dos Citocromos b , Citocromos/metabolismo , Escherichia coli/efeitos dos fármacos , Escherichia coli/genética , Proteínas de Escherichia coli/genética , Proteínas de Escherichia coli/metabolismo , Fermentação/efeitos dos fármacos , Genes Reguladores/genética , NAD/metabolismo , NADH Desidrogenase/metabolismo , Oxirredução/efeitos dos fármacos , Oxigênio/farmacologia , Complexo Piruvato Desidrogenase/biossíntese , Ácido Pirúvico/metabolismo , Proteínas Repressoras/genética , Proteínas Repressoras/metabolismo
6.
Zygote ; 22(2): 266-74, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-23186935

RESUMO

The POU family subclass V (POU-V) proteins have important roles in maintaining cells in an undifferentiated state. In Xenopus, expression of the POU-V protein Oct60 was detected in oocytes and was found to decrease in blastula- to gastrula-stage embryos. In addition, Oct60 overexpression inhibits some signals in early embryogenesis, including Activin/Nodal, BMP, and Wnt signalling. In this report, we analysed mechanisms of Oct60 promoter activation and discovered that Oct60 transcription was activated ectopically in somatic nuclei by oocyte extract treatment. Promoter assays demonstrated that Oct60 transcription was activated in oocytes specifically and that this activation was dependent on an Octamer-Sox binding motif. ChIP assays showed that the Oct60 protein binds the motif. These results suggest that Oct60 transcription is regulated by a positive-feedback loop in Xenopus oocytes.


Assuntos
Embrião não Mamífero/fisiologia , Retroalimentação Fisiológica , Regulação da Expressão Gênica no Desenvolvimento , Oócitos/fisiologia , Transcrição Gênica/genética , Proteínas de Xenopus/metabolismo , Xenopus laevis/embriologia , Xenopus laevis/metabolismo , Animais , Sequência de Bases , Blástula/citologia , Blástula/fisiologia , Imunoprecipitação da Cromatina , Embrião não Mamífero/citologia , Feminino , Gástrula/citologia , Gástrula/fisiologia , Luciferases , Dados de Sequência Molecular , Oócitos/citologia , Fatores do Domínio POU , Regiões Promotoras Genéticas/genética , RNA Mensageiro/genética , Reação em Cadeia da Polimerase em Tempo Real , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Homologia de Sequência do Ácido Nucleico , Transdução de Sinais , Proteínas de Xenopus/genética , Xenopus laevis/genética
7.
Reprod Sci ; 14(4): 349-57, 2007 May.
Artigo em Inglês | MEDLINE | ID: mdl-17644807

RESUMO

Endometrial cancer is associated with both EGFR and HER2 receptor activation. The EGFR and HER2 genes could be disease susceptibility candidate genes for this cancer. This study was conducted to investigate a possible association between EGFR and HER2 gene polymorphisms and endometrial cancer and the influence of these polymorphisms on the clinical outcome of endometrial cancer patients in a Japanese population. The authors compare the genotype distributions and allele frequencies of the EGFR +2073 A/T and HER2 +655 A/G polymorphisms in 116 endometrial cancer patients and 213 controls using polymerase chain reaction-restriction fragment length polymorphism (RFLP) analysis. RFLP results were confirmed by direct DNA sequencing. Of the 116 patients, 76 (65.5%) could be followed up. Disease-free survival estimates were computed using the Kaplan-Meier method, and differences between survival periods were assessed using the log-rank test. No significant differences were observed in either genotype distributions or allele frequencies in the EGFR +2073 A/T and HER2 +655 A/G polymorphisms between endometrial cancer patients and controls. The stratification by histological types and staging failed to identify significant differences between endometrial cancer patients and controls. No statistical differences were noted between these polymorphisms and disease-free survival (Kaplan-Meier log-rank test P = .55 and .66, for the EGFR +2073 A/T and HER2 +655 A/G, respectively). These results suggest that the EGFR +2073 A/T and HER2 +655 A/G polymorphisms are not associated with endometrial cancer in a Japanese population. These conclusions are based on relatively small numbers and will require verification from additional independent studies.


Assuntos
Neoplasias do Endométrio/genética , Receptores ErbB/genética , Polimorfismo Genético , Receptor ErbB-2/genética , Adenina , Adulto , Povo Asiático , Neoplasias do Endométrio/patologia , Feminino , Genes erbB-2 , Guanina , Humanos , Japão , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Polimorfismo de Nucleotídeo Único , Valores de Referência
8.
Acta Obstet Gynecol Scand ; 86(1): 22-5, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17230284

RESUMO

OBJECTIVE: To evaluate the pregnancy outcome of uterine arterial embolization followed by selective hysteroscopic removal of a placental polyp. METHODS: Thirteen patients of placental polyp with abundant blood flow, which was diagnosed by ultrasound with color Doppler imaging, were studied. They underwent uterine arterial embolization followed by selective hysteroscopic removal of the polyp. Uterine arterial embolization was carried out using an absorbable gelatin sponge. Selective removal via hysteroscopy was performed on the following day, using the cutting loop with or without electrical stimulation. The polyp was gradually resected to the level of the surrounding endometrium. RESULTS: Complete removal of the placental polyp was achieved in all patients. The presence of placental polyp was confirmed by pathologic examination. The operative time ranged from 20 to 53 min. In all cases, no complications were noted and the bleeding was minimal during and immediately after the procedure. Postoperative ultrasound demonstrated a uterine cavity free of residual mass in each case. The seven patients with complete gestation gave birth to health babies. No recurrence of placental polyp was observed. CONCLUSIONS: Selective removal directed via hysteroscopy after reduction of blood supply by uterine arterial embolization provides a safe and effective method to minimize bleeding, and can preserve future fertility and successful uneventful pregnancies in the treatment of placental polyp with abundant blood flow.


Assuntos
Embolização Terapêutica/métodos , Histeroscopia/métodos , Doenças Placentárias/terapia , Pólipos/terapia , Complicações Neoplásicas na Gravidez/terapia , Adulto , Feminino , Idade Gestacional , Humanos , Hemorragia Pós-Parto/prevenção & controle , Gravidez , Resultado da Gravidez
9.
Acta Obstet Gynecol Scand ; 85(11): 1310-4, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-17091409

RESUMO

OBJECTIVES: To determine the efficacy of intravenous oxytocin administration compared with intravenous methylergometrine administration for the prevention of postpartum hemorrhage (PPH), and the significance of administration at the end of the second stage of labor compared with that after the third stage. METHODS: A prospective study was undertaken: two major groups (oxytocin group and methylergometrine group) of 438 women with singleton pregnancy and vaginal delivery were studied during a 15-month period. These two groups were subdivided into three subgroups: 1. intravenous injection (two minutes) group immediately after the delivery of the fetal anterior shoulder, 2. intravenous injection (two minutes) group immediately after the delivery of the placenta, and 3. drip infusion (20 min) group immediately after the delivery of the fetal head. In each group, quantitative postpartum blood loss, frequencies of blood loss >500 ml, and need of additional uterotonic treatment were evaluated. RESULTS: As compared with methylergometrine, oxytocin administration was associated with a significant reduction in postpartum blood loss and in frequency of blood loss >500 ml. The risk of PPH was significantly reduced with intravenous injection of oxytocin after delivery of the fetal anterior shoulder, compared with intravenous injection of oxytocin after expulsion of the placenta (OR 0.33, 95%CI 0.11-0.98) and intravenous injection of methylergometrine after delivery of the fetal anterior shoulder (OR 0.31, 95%CI 0.11-0.85). CONCLUSIONS: Intravenous injection of 5 IU oxytocin immediately after delivery of fetal anterior shoulder is the treatment of choice for prevention of PPH in patients with natural course of labor.


Assuntos
Metilergonovina/administração & dosagem , Ocitócicos/administração & dosagem , Ocitocina/administração & dosagem , Hemorragia Pós-Parto/prevenção & controle , Adulto , Esquema de Medicação , Feminino , Humanos , Infusões Intravenosas , Injeções Intravenosas , Terceira Fase do Trabalho de Parto , Gravidez
10.
J Soc Gynecol Investig ; 13(7): 523-9, 2006 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-16990034

RESUMO

OBJECTIVE: The matrix metalloproteinases (MMPs) are a family of zinc-dependent proteases that degrade all the components of the extracellular matrix (ECM). Several studies have demonstrated association between MMP gene polymorphisms and various cancers. The object of this study was to investigate whether the MMP-1 and MMP-9 gene promoter polymorphisms are associated with endometrial carcinomas in a Japanese population. METHODS: We compared the allele frequencies and genotype distributions of each single nucleotide polymorphism in the promoter regions of MMP-1 (-1607 1G/2G) and MMP-9 (-1562 C/T) in 107 endometrial carcinoma cases and 213 controls using polymerase chain reaction-restriction fragment-length polymorphism (PCR-RFLP) analysis. RESULTS: The allele frequencies of MMP-1 -1607 2G and MMP-9 -1562T were 64.0% and 10.7% in the cases and 70.0% and 16.7% in the controls, respectively. No significant differences in the allele frequencies or genotype distributions were found between cases and controls for the MMP-1 -1607 1G/2G polymorphism. However, a small but significant difference in the allele frequency of the MMP-9 -1562T allele was noted between cases and controls (P = .046; odds ratio [OR] = 1.01; 95% confidence interval [CI], 1.01 to 2.73). Stratification by histology revealed a significant difference in the frequency of the MMP-9 -1562T allele between endometrioid carcinoma cases (10.2%) and controls (P = .043; OR = 1.76; 95% CI, 1.02 to 3.03); we did not find a significant difference in the frequency of the MMP-9 -1562T allele between non-endometrioid carcinoma cases (13.2%) and controls. CONCLUSION: These results suggest that the MMP-9 -1562 C/T polymorphism may be associated with susceptibility to endometrioid carcinoma in the Japanese population.


Assuntos
Povo Asiático/genética , Neoplasias do Endométrio/genética , Metaloproteinase 1 da Matriz/genética , Metaloproteinase 9 da Matriz/genética , Polimorfismo de Fragmento de Restrição , Estudos de Casos e Controles , Feminino , Frequência do Gene , Genótipo , Humanos , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase , Regiões Promotoras Genéticas
11.
Int J Gynecol Pathol ; 25(3): 230-2, 2006 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-16810058

RESUMO

Although there are several reports of Brenner tumor showing estrogen activities, it is an extremely rare cause of androgen excess leading to virilism, and the source or mechanism of its androgen production is also unknown at present. A 74-year-old woman presented with lower abdominal pain and increased facial hair growth of 6-month duration. Bilateral ovarian tumors were detected, and her serum testosterone (1.7 ng/mL) and estradiol (75 pg/mL) levels were elevated. Bilateral salpingo-oophorectomy was performed. The ovarian tumors were diagnosed as benign Brenner tumor associated with fibrothecoma-like and luteinized stromal cells. Postoperatively, the serum testosterone and estradiol levels decreased. Immunohistochemically, fibrothecoma-like stromal cells were positive for cytochrome P-450 aromatase, which catalyzes the conversion from androgen to estrogen, and negative for c-Jun protein, which has recently reported to attenuate estrogen biosynthesis by directly down-regulating transcription of the aromatase gene. On the other hand, luteinized stromal cells were negative for cytochrome P-450 aromatase and positive for c-Jun protein. It is suggested that androgen is produced mainly in the luteinized stromal cells, because androgen is not converted to estrogen caused by suppression of aromatase biosynthesis by c-Jun.


Assuntos
Androgênios/análise , Tumor de Brenner/complicações , Neoplasias Ovarianas/complicações , Pós-Menopausa/fisiologia , Virilismo/etiologia , Idoso , Androgênios/sangue , Aromatase/análise , Tumor de Brenner/química , Tumor de Brenner/fisiopatologia , Estradiol/análise , Estradiol/sangue , Feminino , Humanos , Neoplasias Ovarianas/química , Neoplasias Ovarianas/fisiopatologia , Proteínas Proto-Oncogênicas c-jun/análise , Células Estromais/química , Células Estromais/patologia , Testosterona/análise , Testosterona/sangue , Virilismo/fisiopatologia
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