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1.
Phys Rev Lett ; 130(13): 132502, 2023 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-37067317

RESUMO

The new isotope ^{241}U was synthesized and systematic atomic mass measurements of nineteen neutron-rich Pa-Pu isotopes were performed in the multinucleon transfer reactions of the ^{238}U+^{198}Pt system at the KISS facility. The present experimental results demonstrate the crucial role of the multinucleon transfer reactions for accessing unexplored neutron-rich actinide isotopes toward the N=152 shell gap in this region of nuclides.

2.
Phys Rev Lett ; 128(15): 152701, 2022 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-35499908

RESUMO

The Rare-RI Ring (R3) is a recently commissioned cyclotronlike storage ring mass spectrometer dedicated to mass measurements of exotic nuclei far from stability at Radioactive Isotope Beam Factory (RIBF) in RIKEN. The first application of mass measurement using the R3 mass spectrometer at RIBF is reported. Rare isotopes produced at RIBF-^{127}Sn, ^{126}In, ^{125}Cd, ^{124}Ag, ^{123}Pd-were injected in R3. Masses of ^{126}In, ^{125}Cd, and ^{123}Pd were measured whereby the mass uncertainty of ^{123}Pd was improved. This is the first reported measurement with a new storage ring mass spectrometry technique realized at a heavy-ion cyclotron and employing individual injection of the preidentified rare nuclei. The latter is essential for the future mass measurements of the rarest isotopes produced at RIBF. The impact of the new ^{123}Pd result on the solar r-process abundances in a neutron star merger event is investigated by performing reaction network calculations of 20 trajectories with varying electron fraction Y_{e}. It is found that the neutron capture cross section on ^{123}Pd increases by a factor of 2.2 and ß-delayed neutron emission probability, P_{1 n}, of ^{123}Rh increases by 14%. The neutron capture cross section on ^{122}Pd decreases by a factor of 2.6 leading to pileup of material at A=122, thus reproducing the trend of the solar r-process abundances. The trend of the two-neutron separation energies (S_{2n}) was investigated for the Pd isotopic chain. The new mass measurement with improved uncertainty excludes large changes of the S_{2n} value at N=77. Such large increase of the S_{2n} values before N=82 was proposed as an alternative to the quenching of the N=82 shell gap to reproduce r-process abundances in the mass region of A=112-124.

3.
Phys Rev Lett ; 125(19): 192505, 2020 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-33216598

RESUMO

Mass-separated ^{187}Ta_{114} in a high-spin isomeric state has been produced for the first time by multinucleon transfer reactions, employing an argon gas-stopping cell and laser ionization. Internal γ rays revealed a T_{1/2}=7.3±0.9 s isomer at 1778±1 keV, which decays through a rotational band with perturbations associated with the approach to a prolate-oblate shape transition. Model calculations show less influence from triaxiality compared to heavier elements in the same mass region. The isomer-decay reduced E2 hindrance factor f_{ν}=27±1 supports the interpretation that axial symmetry is approximately conserved.

4.
Phys Rev Lett ; 120(15): 152501, 2018 Apr 13.
Artigo em Inglês | MEDLINE | ID: mdl-29756864

RESUMO

The masses of ^{246}Es, ^{251}Fm, and the transfermium nuclei ^{249-252}Md and ^{254}No, produced by hot- and cold-fusion reactions, in the vicinity of the deformed N=152 neutron shell closure, have been directly measured using a multireflection time-of-flight mass spectrograph. The masses of ^{246}Es and ^{249,250,252}Md were measured for the first time. Using the masses of ^{249,250}Md as anchor points for α decay chains, the masses of heavier nuclei, up to ^{261}Bh and ^{266}Mt, were determined. These new masses were compared with theoretical global mass models and demonstrated to be in good agreement with macroscopic-microscopic models in this region. The empirical shell gap parameter δ_{2n} derived from three isotopic masses was updated with the new masses and corroborates the existence of the deformed N=152 neutron shell closure for Md and Lr.

5.
Clin Exp Immunol ; 190(2): 235-243, 2017 11.
Artigo em Inglês | MEDLINE | ID: mdl-28677145

RESUMO

Nerve growth factor (NGF) functions to modulate osteoarthritis (OA)-associated pain. Although recent studies suggest that tumour necrosis factor (TNF)-α and interleukin (IL)-1ß mediate NGF activity in human synovial fibroblasts, the regulation of NGF expression in human synovial macrophages remains unclear. Here, we examined the role of macrophages in the production and regulation of synovial (SYN) NGF in osteoarthritic knee joints by examining the mRNA expression of TNF-α and IL-1ß in freshly isolated CD14-positive (macrophage-rich fraction) and CD14-negative cells (fibroblast-rich fraction) in synovial tissue from OA patients by quantitative polymerase chain reaction. We also examined the effects of IL-1ß and TNF-α on NGF mRNA expression in cultured CD14-positive (macrophage-rich fraction) and CD14-negative cells (fibroblast-rich fraction). In addition, to examine the contribution of macrophages to NGF, TNF-α and IL-1ß expression, we injected clodronate liposomes systemically into STR/Ort mice, an osteoarthritis animal model, to deplete macrophages. TNF-α and IL-1ß mRNA levels in CD14-positive cells from the SYN of OA patients was significantly higher than that in CD14-negative cells, while NGF expression did not differ markedly between the two cell fractions. In addition, treatment of human cultured CD14-positive and -negative cells with IL-1ß and TNF-α enhanced NGF mRNA and protein levels. Expression of NGF, IL-1ß and TNF-α was also reduced significantly in STR/Ort mice upon macrophage depletion. These findings suggest that IL-1ß and TNF-α regulate NGF expression and production in synovial macrophages and fibroblasts in osteoarthritic joints.


Assuntos
Macrófagos/metabolismo , Fator de Crescimento Neural/biossíntese , Fator de Crescimento Neural/genética , Osteoartrite do Joelho/metabolismo , Osteoartrite/metabolismo , Membrana Sinovial/imunologia , Idoso , Idoso de 80 Anos ou mais , Animais , Células Cultivadas , Ácido Clodrônico/administração & dosagem , Modelos Animais de Doenças , Feminino , Fibroblastos/efeitos dos fármacos , Regulação da Expressão Gênica , Humanos , Interleucina-1beta/genética , Interleucina-1beta/metabolismo , Interleucina-1beta/farmacologia , Receptores de Lipopolissacarídeos/imunologia , Lipossomos , Macrófagos/efeitos dos fármacos , Macrófagos/imunologia , Masculino , Camundongos , Fator de Crescimento Neural/imunologia , Osteoartrite/imunologia , Osteoartrite do Joelho/imunologia , Reação em Cadeia da Polimerase , Membrana Sinovial/metabolismo , Fator de Necrose Tumoral alfa/genética , Fator de Necrose Tumoral alfa/metabolismo , Fator de Necrose Tumoral alfa/farmacologia
6.
Gen Comp Endocrinol ; 227: 16-26, 2016 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-26474923

RESUMO

Seasonal breeding is widespread in vertebrates and involves sequential development of the gonads, onset of breeding activities (e.g. cycling in females) and then termination resulting in regression of the reproductive system. Whereas males generally show complete spermatogenesis prior to and after onset of breeding, females of many vertebrate species show only partial ovarian development and may delay onset of cycling (e.g. estrous), yolk deposition or germinal vesicle breakdown until conditions conducive for ovulation and onset of breeding are favorable. Regulation of this "brake" on the onset of breeding remains relatively unknown, but could have profound implications for conservation efforts and for "mismatches" of breeding in relation to global climate change. Using avian models it is proposed that a brain peptide, gonadotropin-inhibitory hormone (GnIH), may be the brake to prevent onset of breeding in females. Evidence to date suggests that although GnIH may be involved in the regulation of gonadal development and regression, it plays more regulatory roles in the process of final ovarian development leading to ovulation, transitions from sexual to parental behavior and suppression of reproductive function by environmental stress. Accumulating experimental evidence strongly suggests that GnIH inhibits actions of gonadotropin-releasing hormones on behavior (central effects), gonadotropin secretion (central and hypophysiotropic effects), and has direct actions in the gonad to inhibit steroidogenesis. Thus, actual onset of breeding activities leading to ovulation may involve environmental cues releasing an inhibition (brake) on the hypothalamo-pituitary-gonad axis.


Assuntos
Mudança Climática , Hormônios Hipotalâmicos/metabolismo , Reprodução/fisiologia , Aves Canoras/fisiologia , Animais , Proteínas Aviárias/metabolismo , Estro/fisiologia , Feminino , Gônadas/metabolismo , Masculino , Estações do Ano , Espermatogênese/fisiologia
7.
Pharmazie ; 70(7): 466-70, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-26373207

RESUMO

Propofol (2,6-diisopropylphenol) is a short-acting anesthetic commonly used in clinical practice, and is rapidly metabolized into glucuronide by UDP-glucuronosyltransferase (UGT). In the present study, propofol glucuronidation was examined in the liver microsomes of male and female humans, monkeys, rats, and mice. The kinetics of propofol glucuronidation by liver microsomes fit the substrate inhibition model for humans and mice, the Hill model for monkeys, and the isoenzyme (biphasic) model for rats. The K(m), V(max), and CL(int) values of human liver microsomes were 50 µM, 5.6 nmol/min/mg protein, and 110 µL/min/mg protein, respectively, for males, and 46 µM, 6.0 nmol/min/mg protein, and 130 µL/min/mg protein, respectively, for females. The rank order of the CL(int) or CL(max) (in vitro clearance) values of liver microsomes was mice humans > monkeys > rats (high-affinity phase) rats (low-affinity phase) in both males and females. Although no significant sex differences were observed in the values of kinetic parameters in any animal species, the in vitro clearance values of liver microsomes were males < females in humans, males = females in rats (low-affinity phase), and males > females in monkeys, rats (high-affinity phase), and mice. These results demonstrated that the kinetic profile of propofol glucuronidation by liver microsomes markedly differed among humans, monkeys, rats, and mice, and suggest that species and sex differences exist in the roles of UGT isoform(s), including UGT1A9, involved in its metabolism.


Assuntos
Anestésicos Intravenosos/farmacocinética , Microssomos Hepáticos/metabolismo , Propofol/farmacocinética , Adulto , Idoso , Animais , Feminino , Glucuronídeos/metabolismo , Humanos , Macaca fascicularis , Masculino , Camundongos , Pessoa de Meia-Idade , Ratos , Ratos Wistar , Caracteres Sexuais , Especificidade da Espécie , Adulto Jovem
8.
Lupus ; 23(11): 1124-32, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24860121

RESUMO

The objective of this study was to clarify the long-term outcome in patients with lupus nephritis (LN) according to the International Society of Nephrology and Renal Pathology Society classification. This retrospective analysis comprised 186 Japanese patients given a diagnosis of LN by renal specimen with a mean observation period of 12 years. Primary end point was defined as death or end-stage renal disease, and standardized mortality ratios were calculated. Five patients presented with histopathological class I, 62 with II, 21 with III or III+V, 73 with IV or IV+V and 25 with V. Fourteen deaths occurred, corresponding to an overall standardized mortality ratio of 3.59 (95% confidence interval 2.02-5.81, p < 0.0001). Kaplan-Meier analysis revealed a 10-year overall survival of 95.7%. Nephrotic proteinuria (≥3.5 g/day) at baseline was identified as an independent poor prognostic factor for overall survival in Cox regression analysis. Kaplan-Meier analysis revealed a 10-year renal survival as 94.3%. Male gender and nephrotic proteinuria at baseline were identified as independent poor prognostic factors for renal survival in Cox regression analysis. In conclusion, LN was associated with a 3.59-fold increase in mortality compared with the general population. Male gender and nephrotic proteinuria were predictive for poor renal outcome.


Assuntos
Falência Renal Crônica/epidemiologia , Nefrite Lúpica/fisiopatologia , Proteinúria/epidemiologia , Adolescente , Adulto , Idoso , Criança , Feminino , Humanos , Japão , Estimativa de Kaplan-Meier , Falência Renal Crônica/etiologia , Nefrite Lúpica/mortalidade , Masculino , Pessoa de Meia-Idade , Prognóstico , Modelos de Riscos Proporcionais , Proteinúria/etiologia , Estudos Retrospectivos , Fatores de Risco , Fatores Sexuais , Taxa de Sobrevida , Fatores de Tempo , Adulto Jovem
9.
Pharmazie ; 69(11): 829-32, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25985579

RESUMO

Propofol (2,6-diisopropylphenol) is intravenously administered for anesthetic induction and maintenance, and is rapidly metabolized into its glucuronide, mainly by UDP-glucuronosyltransferase 1A9 (UGT1A9). In this study, propofol glucuronidation by liver microsomes (HLM), intestinal microsomes (HIM) and kidney microsomes (HKM) of humans were examined. The expression of UGT1A9 protein in HLM, HIM and HKM was analyzed by immunoblotting. The staining band intensities for UGT1A9 of HIM and HKM were 12% and 119% those of HLM, respectively. The kinetics of propofol glucuronidation by HLM and HKM exhibited substrate inhibition, whereas the kinetics by HIM followed the Michaelis-Menten model. The K(m), V(max) and CL(int) values of HLM were 41.8 µM, 5.21 nmol/min/mg protein and 126 µl/min/mg protein, respectively. The K(m) value of HIM was significantly higher (6.7-fold) than that of HLM, and the V(max) and CL(int) values were significantly lower (56% and 8.3%, respectively) than those of HLM. The K(m) value of HKM was comparable to that of HLM, and the V(max) and CL(int) values were significantly higher (2.1- and 3.7-fold, respectively) than those of HLM, respectively. These findings suggest that UGT1A9 expressed in the kidney as well as in the liver plays an important role in propofol glucuronidation. The information gained in this study should contribute to an appropriate use of drugs metabolized by UGT1A9.


Assuntos
Anestésicos Intravenosos/metabolismo , Glucuronosiltransferase/metabolismo , Microssomos/metabolismo , Propofol/metabolismo , Anestésicos Intravenosos/farmacocinética , Glucuronídeos/metabolismo , Humanos , Técnicas In Vitro , Mucosa Intestinal/metabolismo , Rim/metabolismo , Microssomos Hepáticos , Propofol/farmacocinética , Distribuição Tecidual , UDP-Glucuronosiltransferase 1A
10.
Vet Pathol ; 49(6): 1070-3, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22677877

RESUMO

An alpaca was presented with a history of respiratory difficulty and death. Histology of the phrenic nerves and diaphragm revealed degenerative changes consistent with denervation atrophy, and a diagnosis of diaphragmatic paralysis was established. No gross or histological abnormalities were observed in the spinal cord or other organs. The etiology of the phrenic nerve neuropathy could not be determined. The need to examine phrenic nerves and diaphragm in camelids with respiratory distress is emphasized, as failure to examine these samples will preclude a diagnosis of diaphragmatic paralysis.


Assuntos
Camelídeos Americanos , Diafragma/patologia , Degeneração Neural/veterinária , Nervo Frênico/patologia , Síndrome do Desconforto Respiratório/veterinária , Paralisia Respiratória/veterinária , Animais , Atrofia/veterinária , Diagnóstico Diferencial , Diafragma/fisiopatologia , Evolução Fatal , Feminino , Degeneração Neural/patologia , Nervo Frênico/fisiopatologia , Síndrome do Desconforto Respiratório/diagnóstico , Síndrome do Desconforto Respiratório/patologia , Paralisia Respiratória/diagnóstico , Paralisia Respiratória/patologia
11.
Sci Immunol ; 6(64): eabb6444, 2021 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-34623903

RESUMO

Interleukin-27 (IL-27) is an immunoregulatory cytokine whose essential function is to limit immune responses. We found that the gene encoding cholesterol 25-hydroxylase (Ch25h) was induced in CD4+ T cells by IL-27, enhanced by transforming growth factor­ß (TGF-ß), and antagonized by T-bet. Ch25h catalyzes cholesterol to generate 25-hydroxycholesterol (25OHC), which was subsequently released to the cellular milieu, functioning as a modulator of T cell response. Extracellular 25OHC suppressed cholesterol biosynthesis in T cells, inhibited cell growth, and induced nutrient deprivation cell death without releasing high-mobility group box 1 (HMGB1). This growth inhibitory effect was specific to actively proliferating cells with high cholesterol demand and was reversed when extracellular cholesterol was replenished. Ch25h-expressing CD4+ T cells that received IL-27 and TGF-ß signals became refractory to 25OHC-mediated growth inhibition in vitro. Nonetheless, IL-27­treated T cells negatively affected viability of bystander cells in a paracrine manner, but only if the bystander cells were in the early phases of activation. In mouse models of skin inflammation due to autoreactive T cells or chemically induced hypersensitivity, genetic deletion of Ch25h or Il27ra led to worse outcomes. Thus, Ch25h is an immunoregulatory metabolic switch induced by IL-27 and dampens excess bystander T effector expansion in tissues through its metabolite derivative, 25OHC. This study reveals regulation of cholesterol metabolism as a modality for controlling tissue inflammation and thus represents a mechanism underlying T cell immunoregulatory functions.


Assuntos
Linfócitos T CD4-Positivos/metabolismo , Mediadores da Inflamação/metabolismo , Inflamação/metabolismo , Interleucina-27/metabolismo , Pele/metabolismo , Esteroide Hidroxilases/metabolismo , Animais , Colesterol/biossíntese , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Esteroide Hidroxilases/genética
12.
Ann Oncol ; 21(6): 1262-1266, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19854722

RESUMO

BACKGROUND: Capecitabine (X) and docetaxel (T) have demonstrated a synergistic effect in preclinical models and a survival benefit in metastatic breast cancer. This study's purpose was to determine the efficacy of X and T followed by 5-fluorouracil/epirubicin/cyclophosphamide (FEC) in the preoperative setting. PATIENTS AND METHODS: Patients with stage II/III breast cancer received four cycles of XT (capecitabine 1650 mg/m(2) on days 1-14 and docetaxel 60 mg/m(2) on day 8 every 3 weeks), followed by four cycles of FEC (5-fluorouracil 500 mg/m(2), epirubicin 90 mg/m(2), and cyclophosphamide 500 mg/m(2) on day 1 every 3 weeks). Primary end points were the pathological complete response (pCR) rate and adverse drug reactions. RESULTS: Seventy-four patients were enrolled and 71 patients were assessable for clinical and pathological responses. The overall response rate was 91.5%. The pCR rate was 14.1% (10 of 71). Grade 3/4 neutropenia was observed in 32.4% of patients. The most common grade 3/4 non-hematologic adverse event was hand-foot syndrome, observed in 11.3% of patients. With 29 months median follow-up, 2-year disease-free survival was estimated 85% for all patients. CONCLUSION: These data indicate that the sequential combination of XT followed by FEC is a well-tolerated, effective neoadjuvant treatment of stage II/III breast cancer.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/cirurgia , Carcinoma in Situ/tratamento farmacológico , Carcinoma in Situ/cirurgia , Desoxicitidina/análogos & derivados , Fluoruracila/análogos & derivados , Taxoides/administração & dosagem , Adulto , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Neoplasias da Mama/patologia , Capecitabina , Carcinoma in Situ/patologia , Terapia Combinada , Ciclofosfamida/administração & dosagem , Ciclofosfamida/efeitos adversos , Desoxicitidina/administração & dosagem , Desoxicitidina/efeitos adversos , Docetaxel , Esquema de Medicação , Epirubicina/administração & dosagem , Epirubicina/efeitos adversos , Feminino , Fluoruracila/administração & dosagem , Fluoruracila/efeitos adversos , Humanos , Mastectomia Segmentar , Pessoa de Meia-Idade , Terapia Neoadjuvante , Estadiamento de Neoplasias , Período Pré-Operatório , Taxoides/efeitos adversos , Resultado do Tratamento
13.
Eur Surg Res ; 45(3-4): 344-9, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-21088425

RESUMO

BACKGROUND: The prognostic significance of sentinel lymph node (SLN) micrometastases and the need for axillary lymph node dissection (ALND) on patients with micrometastases in SLNs remain controversial. METHODS: A prospective database of 657 breast cancer patients who underwent SLN biopsy (SLNB) was analyzed. SLNs were detected using a combined method of isosulfan blue dye and small-sized technetium-99m-labeled tin colloid. RESULTS: Micrometastases in SLNs were found in 50 (7.6%) of 657 patients. Twenty-nine (58.0%) of 50 patients with micrometastatic SLNs underwent ALND and no further metastases were found in non-sentinel lymph nodes. Among 21 patients (42.0%) with micrometastatic SLNs who decided to forego ALND, no axillary lymph node recurrence has been observed during a median follow-up time of 47 months. There is no significant difference in recurrence-free survival between the patients with micrometastatic and negative SLNs (p = 0.90). CONCLUSIONS: These data suggest that it may not be necessary to perform ALND on patients with micrometastases in SLNs and that the presence of micrometastases in SLNs may not be associated with prognosis.


Assuntos
Neoplasias da Mama/patologia , Neoplasias da Mama/cirurgia , Metástase Linfática/patologia , Biópsia de Linfonodo Sentinela , Adulto , Idoso , Idoso de 80 Anos ou mais , Axila , Carcinoma Ductal de Mama/patologia , Carcinoma Ductal de Mama/secundário , Carcinoma Ductal de Mama/cirurgia , Bases de Dados Factuais , Intervalo Livre de Doença , Feminino , Humanos , Estimativa de Kaplan-Meier , Excisão de Linfonodo , Pessoa de Meia-Idade , Prognóstico , Estudos Prospectivos
14.
Eur Surg Res ; 44(2): 111-6, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20110718

RESUMO

BACKGROUND: Sentinel lymph node biopsy (SLNB) is commonly performed using radioisotopes and/or blue dye. However, it is still undefined which reagent is more suitable for identifying sentinel lymph nodes (SLN). PATIENTS AND METHODS: A consecutive series of 640 breast cancer patients who had undergone SLNB at the Keio University Hospital from 2001 to 2006 was analyzed. The SLN was identified by a combination of technetium-99m tin colloid and isosulfan blue dye. The correlation between clinicopathological factors and the distribution of radioisotopes and blue dye was analyzed. The single metastatic lymph node revealed by axillary lymph node dissection (ALND) is the 'true SLN', and the distribution of radioisotopes and blue dye to the 'true SLN' was also analyzed. RESULTS: Blue-dye- and radioisotope-positive SLN were identified in 79.6 and 94.7% of the patients, respectively. Taken together, SLN were identified in 625 patients (97.7%) by radioisotope and/or blue dye. No significant correlation was observed between clinicopathological features and the distribution of the reagents. ALND found 73 patients with single lymph node metastasis, and 73 'true SLN' were identified by blue dye in 65.7% (48/73), and by radioisotope in 95.9% (70/73) of the cases. CONCLUSION: These data suggest that radioisotopes are superior to blue dye in detecting SLN in breast cancer.


Assuntos
Neoplasias da Mama/patologia , Neoplasias da Mama/cirurgia , Metástase Linfática/diagnóstico por imagem , Biópsia de Linfonodo Sentinela , Neoplasias da Mama/diagnóstico por imagem , Feminino , Humanos , Metástase Linfática/patologia , Pessoa de Meia-Idade , Invasividade Neoplásica , Estadiamento de Neoplasias , Estudos Prospectivos , Cintilografia , Receptores de Estrogênio/análise , Receptores de Progesterona/análise
15.
Science ; 274(5295): 2075-9, 1996 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-8953037

RESUMO

In Drosophila embryos, germ cell formation is induced by specialized cytoplasm at the posterior of the egg, the pole plasm. Pole plasm contains polar granules, organelles in which maternally produced molecules required for germ cell formation are assembled. An untranslatable RNA, called Polar granule component (Pgc), was identified and found to be localized in polar granules. Most pole cells in embryos produced by transgenic females expressing antisense Pgc RNA failed to complete migration and to populate the embryonic gonads, and females that developed from these embryos often had agametic ovaries. These results support an essential role for Pgc RNA in germline development.


Assuntos
Grânulos Citoplasmáticos/fisiologia , Drosophila/embriologia , Embrião não Mamífero/citologia , Células Germinativas/fisiologia , Oogênese , RNA/fisiologia , Animais , Animais Geneticamente Modificados , Sequência de Bases , Movimento Celular , Polaridade Celular , Grânulos Citoplasmáticos/química , Grânulos Citoplasmáticos/genética , DNA Complementar/genética , Drosophila/genética , Embrião não Mamífero/ultraestrutura , Desenvolvimento Embrionário , Feminino , Genes de Insetos , Masculino , Dados de Sequência Molecular , Mutação , Ovário/embriologia , Óvulo/fisiologia , RNA/análise , RNA/genética , RNA Antissenso/genética , RNA Mitocondrial , RNA Ribossômico/análise
16.
Climacteric ; 12(2): 146-52, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19105055

RESUMO

OBJECTIVE: The level of serum urate is generally elevated in postmenopausal individuals. In addition to estrogen, other menopause-related factors may also affect uric acid metabolism in postmenopausal females. Accordingly, we investigated factors related to increased serum urate levels in addition to lack of estrogen. SUBJECTS AND METHODS: We studied 448 females who participated in an annual health check-up. None were being treated for gout, hyperuricemia, or diabetes mellitus, and no subjects had a history of hysterectomy and had never used estrogens or progestins. Body mass index (BMI), homeostasis model of insulin resistance (HOMA-R), and ethanol ingestion were investigated in all subjects, while information regarding menopause status was also obtained. RESULTS: Serum urate levels rose from the age of 46 to 60 years in the subjects. Multivariate regression analysis showed that BMI, HOMA-R, ethanol ingestion and menopause were independently associated with serum urate level. In addition, BMI and HOMA-R were higher in postmenopausal, as compared to premenopausal, subjects. CONCLUSION: Our results suggest that menopause-related insulin resistance, obesity and ethanol ingestion as well as menopause may contribute to an increase in level of serum urate in postmenopausal Japanese women.


Assuntos
Pós-Menopausa/sangue , Ácido Úrico/sangue , Adulto , Envelhecimento/sangue , Consumo de Bebidas Alcoólicas , Índice de Massa Corporal , Feminino , Homeostase , Humanos , Resistência à Insulina , Japão , Pessoa de Meia-Idade , Análise Multivariada , Análise de Regressão
17.
Rev Sci Instrum ; 90(11): 115104, 2019 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-31779376

RESUMO

We demonstrated efficient two-color two-step laser ionization schemes in the combined use of λ1 ∼ 250 nm and λ2 = 307.9 nm, which are applicable to heavy refractory elements with an atomic number in the wide range of Z = 69-78. We investigated newly observed ionization schemes of tantalum and tungsten atoms in an argon-gas-cell-based laser ion source for the efficient ionization of atoms of unstable nuclei through the two-color two-step laser resonance ionization technique. We experimentally determined the ionization cross sections from the measured saturation curves by solving the rate equations for the ground, intermediate, and ionization continuum populations. Hyperfine structures of these elements were also studied to deduce the isotope-shift, pressure-shift, and pressure-broadening in the resonance spectra of the excitation transitions in the argon gas cell. The electronic factor F255 of the excitation transition λ1 = 255.2115 nm between the ground and intermediate states was deduced from the measured isotope shifts of stable 182,183,184,186W isotopes. The ionization schemes investigated here are applicable to extract any isotopes of these elements by considering the measured pressure shift and nuclear isotope shift in optimizing the wavelength λ1.

18.
J Dermatol Sci ; 52(1): 21-30, 2008 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-18502615

RESUMO

BACKGROUND: Giant congenital nevocellular nevi (GCNN) are histologically characterized by the broad distribution of nevus cells in the epidermis and dermis. OBJECTIVE: To characterize E-cadherin in GCNN and define its role in nevic cell migrations. METHODS: Twenty-four cases were immunohistochemically examined and in five cases cells were isolated for primary culture for migration assays. RESULTS: The nevus cells in the superficial region showed the immunoreactivity of E-cadherin in a membranous pattern, but those in the deep part of dermis had little immunoreactivity. Ultra-structural analysis of the superficial nevus cells revealed that E-cadherin immunodeposits in the fibrillar processes around the cell body in a spotted pattern. This distribution pattern is quite different from that in the adherens junction of skin squamous epithelial cells. Boyden chamber experiments were performed using primary cultures of intradermal nevus cells. EDTA pretreatment reduced cell migration to the E-cadherin positive side when the E-cadherin positive population was relatively large in the primary cultures. CONCLUSIONS: These results indicate that E-cadherin in the nevus cells may affect nevus cell motility rather than intercellular attachment.


Assuntos
Caderinas/metabolismo , Movimento Celular , Epiderme/metabolismo , Células Epiteliais/metabolismo , Nevo Intradérmico/congênito , Nevo Intradérmico/metabolismo , beta Catenina/metabolismo , Adulto , Pré-Escolar , Células Epidérmicas , Células Epiteliais/citologia , Células Epiteliais/ultraestrutura , Humanos , Lactente , Microscopia Imunoeletrônica , Nevo Intradérmico/patologia , Neoplasias Cutâneas/congênito , Neoplasias Cutâneas/metabolismo , Neoplasias Cutâneas/patologia
19.
Curr Biol ; 8(20): 1117-20, 1998 Oct 08.
Artigo em Inglês | MEDLINE | ID: mdl-9778528

RESUMO

In Xenopus, factors with the ability to establish the germ line are localized in the vegetal pole cytoplasm, or germ plasm, of the early embryo [1-3]. The germ plasm of Xenopus, and of many other animal species including Drosophila, contains electron-dense germinal granules which may be essential for germ-line formation [4-5]. Several components of the germinal granules have so far been identified in Drosophila [6-10]. One of these is mitochondrial large ribosomal RNA (mtlrRNA), which is present in the germinal granules (polar granules) during the cleavage stage until the formation of the germ-line progenitors or pole cells [8-9]. MtlrRNA has been identified as a factor that induces pole cells in embryos that have been sterilized by ultraviolet radiation [11]. The reduction of mtlrRNA in germ plasm by injecting anti-mtlrRNA ribozymes into embryos leads to the inability of these embryos to form pole cells [12]. These observations clearly show that mtlrRNA is essential for pole cell formation in Drosophila. Here, we report that mtlrRNA is enriched in germ plasm of Xenopus embryos from the four-cell stage to the blastula. Furthermore, our electron microscopic studies show that this mtlrRNA is present in the germinal granules during these stages. Thus, mtlrRNA is a common component of germinal granules in Drosophila and Xenopus, suggesting that the mtlrRNA has a role in germ-line development across phylogenetic boundaries.


Assuntos
Mitocôndrias/genética , RNA Ribossômico/metabolismo , RNA/metabolismo , Animais , Polaridade Celular , Citoplasma/metabolismo , Células Germinativas , RNA Mitocondrial , Xenopus laevis
20.
Placenta ; 27(2-3): 333-9, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-16338478

RESUMO

The incidence of choriocarcinoma has decreased over time and therapeutic results have improved about 90% complete remission in patients without extensive metastasis. However, some choriocarcinomas metastasize to other organs and show resistance to chemotherapy, having a poor prognosis despite multidisciplinary treatment. Better methods of early diagnosis for recurrence or micrometastasis, and treatment against cases with intractable gestational trophoblastic neoplasia (GTN) are needed to improve the prognosis. Human chorionic gonadotropin (hCG) is a glycoprotein hormone composed of two dissimilar subunits and a tumor marker to make a diagnosis and monitor therapeutic effect in GTN. Even when hCG levels in the serum become too low to measure with the hCG beta-CTP system which is the most sensitive assay, there are estimated to be approximately 10,000 trophoblastic cells in the body. Residual trophoblast cells may cause symptoms such as bleeding or undergo malignant transformation to choriocarcinoma. Since most monoclonal antibodies developed so far are murine, administration creates human anti-mouse antibodies, resulting in clinical failure. More recent mouse/human chimeric antibodies or humanized antibodies still possess substantial immunogenicity that makes repeated administration difficult. In the present study, KM mice that can produce completely human monoclonal antibodies were used to prepare hCG-specific human monoclonal antibody. This yielded 8-1A, a human monoclonal antibody capable of reacting with intact hCG. In the future, new diagnostic techniques and treatments for chorionic diseases may be developed using this kind of human monoclonal antibody.


Assuntos
Anticorpos Monoclonais/biossíntese , Anticorpos Monoclonais/imunologia , Gonadotropina Coriônica/imunologia , Animais , Anticorpos Monoclonais Humanizados , Western Blotting , Humanos , Imunoquímica , Imunoprecipitação , Camundongos , Camundongos Transgênicos
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