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1.
Phys Rev Lett ; 128(9): 091302, 2022 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-35302802

RESUMO

We search for the signature of parity-violating physics in the cosmic microwave background, called cosmic birefringence, using the Planck data release 4. We initially find a birefringence angle of ß=0.30°±0.11° (68% C.L.) for nearly full-sky data. The values of ß decrease as we enlarge the Galactic mask, which can be interpreted as the effect of polarized foreground emission. Two independent ways to model this effect are used to mitigate the systematic impact on ß for different sky fractions. We choose not to assign cosmological significance to the measured value of ß until we improve our knowledge of the foreground polarization.

2.
Phys Rev Lett ; 124(13): 131301, 2020 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-32302154

RESUMO

Using only cosmic microwave background polarization data from the polarbear experiment, we measure B-mode polarization delensing on subdegree scales at more than 5σ significance. We achieve a 14% B-mode power variance reduction, the highest to date for internal delensing, and improve this result to 22% by applying for the first time an iterative maximum a posteriori delensing method. Our analysis demonstrates the capability of internal delensing as a means of improving constraints on inflationary models, paving the way for the optimal analysis of next-generation primordial B-mode experiments.

3.
Psychol Med ; 45(3): 559-73, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25036366

RESUMO

BACKGROUND: The interactive effect of personal factors and social factors upon suicide risk is unclear. We conducted prospective cohort study to investigate whether the impact of the economic crisis in 1997-1998 upon suicide risk differed according to Neuroticism and Psychoticism personality traits. METHODS: The Miyagi Cohort Study in Japan with a follow-up for 19 years from 1990 to 2008 has 29,432 subjects aged 40-64 years at baseline who completed a questionnaire about various health habits and the Japanese version of the Eysenck Personality Questionnaire - Revised Short Form in 1990. RESULTS: The suicide mortality rate increased from 4.6 per 100,000 person-years before 1998 to 27.8 after 1998. Although both Neuroticism and Psychoticism were significantly associated with an increased risk of mortality during the whole period from 1990 to 2008, the impact of the economic crisis upon suicide risk differed between the Neuroticism and Psychoticism personality traits. Compared with the lowest category, the hazard ratios (HRs) for the highest Neuroticism increased from 0.66 before 1998 to 2.45 after 1998. On the other hand, the HRs for the highest Psychoticism decreased from 7.85 before 1998 to 2.05 after 1998. CONCLUSIONS: The impact of the 1997-1998 economic crisis upon suicide risk differed according to personality. Suicide risk increased among these with higher Neuroticism after the economic crisis, but this was not the case for other personality subscales.


Assuntos
Recessão Econômica/história , Personalidade , Suicídio/tendências , Adulto , Feminino , Comportamentos Relacionados com a Saúde , História do Século XX , Humanos , Japão , Masculino , Pessoa de Meia-Idade , Modelos de Riscos Proporcionais , Estudos Prospectivos , Fatores de Risco , Inquéritos e Questionários
4.
Int J Clin Pract ; 69(8): 820-8, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25521285

RESUMO

BACKGROUND: Several previous studies have suggested that detection of a third heart sound (S3) in patients with chronic congestive heart failure is associated with adverse long-term outcomes. However, the short-term prognostic value of identifying an S3 on admission in patients with acute heart failure (AHF) is not well established. We therefore analysed the in-hospital prognostic value of detecting an S3 on admission in hospitalised patients with AHF. METHODS: The Acute Decompensated Heart Failure Syndromes (ATTEND) study investigators enrolled 4107 patients hospitalised with AHF. Investigators evaluated the presence or absence of an S3 during routine physical examination. RESULTS: On admission to hospital, 1673 patients (41%) had an S3. Patients with an S3 had a higher heart rate, higher serum level of B-type natriuretic peptide and higher creatinine levels than patients without an S3. However, there were no significant differences of systolic blood pressure, serum sodium, haemoglobin, C-reactive protein and total bilirubin between the two groups. Multivariate analysis adjusted for various markers of disease severity revealed that only the presence of an S3 was independently associated with an increase of in-hospital all cause death [adjusted odds ratio (OR), 1.69; 95% confidence interval (CI), 1.19-2.41; p = 0.003] and cardiac death (adjusted OR, 1.66; 95% CI, 1.08-2.54; p = 0.020) among the congestive physical findings related to heart failure (S3, rales, jugular venous distension and peripheral oedema). CONCLUSIONS: Detecting an S3 on admission was independently associated with adverse in-hospital outcomes in patients with AHF. Our findings suggest that careful bedside assessment is clinically meaningful.


Assuntos
Insuficiência Cardíaca/fisiopatologia , Ruídos Cardíacos/fisiologia , Doença Aguda , Idoso , Idoso de 80 Anos ou mais , Biomarcadores/sangue , Pressão Sanguínea/fisiologia , Feminino , Insuficiência Cardíaca/mortalidade , Frequência Cardíaca/fisiologia , Mortalidade Hospitalar , Humanos , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Valor Preditivo dos Testes , Prognóstico
5.
Cytopathology ; 26(6): 354-61, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25376185

RESUMO

OBJECTIVE: Brushing or washing cytology taken at bronchoscopy is a standard diagnostic procedure for lung cancer. The present study evaluated the sensitivity of immunocytochemical diagnosis of lung cancer using bronchial washing materials. METHODS: We collected bronchial washing samples taken at bronchoscopy between July 2012 and July 2013 at Tsukuba University Hospital and studied 106 cases that were finally diagnosed as lung cancer. We collected exfoliated cells using a thin-layer advanced cytology assay system (TACAS(™)) and performed cytological diagnosis using Papanicolaou staining. As controls, we randomly selected 30 tumour-negative cases from among samples collected during the same period. Using these materials, we also examined the expression of stratifin (14-3-3 sigma) (n = 92) and OCIAD2 ovarian immunoreactive antigen domain 2) (n = 106) by immunocytochemistry, as these are considered to be broad spectrum immune markers for lung adenocarcinoma including early invasive lung adenocarcinoma. RESULTS: Using Papanicolaou staining, 52 out of 106 lung cancers (49.1%) were diagnosed as positive. However, positivity was increased to 63.0% by immunocytochemistry using anti-stratifin or anti-OCIAD2 antibodies. Biopsies were taken in 103/106 cases and cancer was diagnosed in 60/103, (58.3%). The sensitivity of stratifin or OCIAD2 was significantly higher than that of Papanicolaou staining (P = 0.027), but immunocytochemistry detected false-positive cells in 3/30 cases (10%) for stratifin and 2/30 cases (7%) for OCIAD2. CONCLUSION: Immunocytochemical staining for stratifin and OCIAD2 improved diagnostic sensitivity for lung cancers but diagnostic specificity was lower than that for cytology alone. The immunostains carried up to a 10% risk of a false-positive result and therefore positive staining must be confirmed by morphological evidence of malignancy.


Assuntos
Proteínas 14-3-3/análise , Adenocarcinoma/diagnóstico , Biomarcadores Tumorais/análise , Exorribonucleases/análise , Neoplasias Pulmonares/diagnóstico , Proteínas de Neoplasias/análise , Adenocarcinoma/química , Adenocarcinoma de Pulmão , Adulto , Idoso , Idoso de 80 Anos ou mais , Líquido da Lavagem Broncoalveolar/química , Broncoscopia , Feminino , Humanos , Imuno-Histoquímica/métodos , Neoplasias Pulmonares/química , Masculino , Pessoa de Meia-Idade , Teste de Papanicolaou , Sensibilidade e Especificidade , Coloração e Rotulagem/métodos
6.
Phys Rev Lett ; 112(7): 071101, 2014 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-24579585

RESUMO

Ultracold neutrons (UCNs) can be bound by the potential of terrestrial gravity and a reflecting mirror. The wave function of the bound state has characteristic modulations. We carried out an experiment to observe the vertical distribution of the UCNs above such a mirror at the Institut Laue-Langevin in 2011. The observed modulation is in good agreement with that prediction by quantum mechanics using the Wigner function. The spatial resolution of the detector system is estimated to be 0.7 µm. This is the first observation of gravitationally bound states of UCNs with submicron spatial resolution.

8.
Clin Exp Obstet Gynecol ; 40(4): 591-5, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24597265

RESUMO

Maternal virilization in pregnancy with or without fetal female pseudohermaphroditism has several etiologies. Of these, pregnancy luteoma is the most common cause of maternal virilization during pregnancy, and approximately 20 cases have been reported in recent years. Moreover, four cases of pregnancy luteomas with female pseudohermaphroditism have been reported. However, the extremely rare steroid cell tumor, not otherwise specified (NOS), has been reported only once as a cause for maternal virilization. Herein, the authors report the first case of maternal virilization with female pseudohermaphroditism associated with steroid cell tumor-NOS along with the clinical course, pathological features, and a review of the literature.


Assuntos
Transtornos 46, XX do Desenvolvimento Sexual/etiologia , Neoplasias Ovarianas/complicações , Complicações Neoplásicas na Gravidez , Virilismo/complicações , Virilismo/diagnóstico , Transtornos 46, XX do Desenvolvimento Sexual/complicações , Adulto , Neoplasias Cerebelares/complicações , Neoplasias Cerebelares/patologia , Neoplasias Cerebelares/cirurgia , Cesárea , Transtornos do Desenvolvimento Sexual , Feminino , Idade Gestacional , Humanos , Recém-Nascido Prematuro , Luteoma/complicações , Imageamento por Ressonância Magnética , Meduloblastoma/complicações , Meduloblastoma/patologia , Meduloblastoma/cirurgia , Neoplasias Ovarianas/patologia , Neoplasias Ovarianas/cirurgia , Gravidez , Testosterona/sangue
9.
Rev Sci Instrum ; 94(6)2023 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-37862532

RESUMO

A half-wave plate (HWP) is often used as a modulator to suppress systematic error in the measurements of cosmic microwave background (CMB) polarization. A HWP can also be used to measure circular polarization (CP) through its optical leakage from CP to linear polarization. The CP of the CMB is predicted from various sources, such as interactions in the Universe and extension of the standard model. Interaction with supernova remnants of population III stars is one of the brightest CP sources. Thus, the observation of the CP of CMB is a new tool for searching for population III stars. In this paper, we demonstrate the improved measurement of the leakage coefficient using the transmission measurement of an actual HWP in the laboratory. We measured the transmittance of linearly polarized light through the HWP used in Polarbear in the frequency range of 120-160 GHz. We evaluate the properties of the HWP by fitting the data with a physical model using the Markov Chain Monte Carlo method. We then estimate the band-averaged CP leakage coefficient using the physical model. We find that the leakage coefficient strongly depends on the spectra of CP sources. We thus calculate the maximum fractional leakage coefficient from CP to linear polarization as 0.133 ± 0.009 in the Rayleigh-Jeans spectrum. The nonzero value shows that Polarbear has a sensitivity to CP. Additionally, because we use the bandpass of detectors installed in the telescope to calculate the band-averaged values, we also consider systematic effects in the experiment.

10.
Curr Opin Cell Biol ; 7(2): 156-62, 1995 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-7612266

RESUMO

Cytokine receptors transduce signals to the cell interior upon binding of their cognate ligands, eventually leading to cellular responses such as cellular proliferation, differentiation and other effector functions. Most of the cytokine receptors, including the interleukin (IL)-2 receptor, consist of two or more distinct subunits, yet none possess any known catalytic activity such as protein tyrosine kinase activity. Significant advances have recently been made in identifying the multiple signaling molecules, including protein tyrosine kinases, that couple with the cytoplasmic regions of the IL-2 receptor, although their exact roles in cytokine signaling are still not fully understood. Another important development in the understanding of IL-2 signaling is the identification of the target genes, including nuclear proto-oncogenes. Furthermore, structure-function analyses of the components of the IL-2 receptor have enabled the dissection of multiple intracellular signaling pathways that lead to the induction of the respective target genes.


Assuntos
Interleucina-2/fisiologia , Proteínas Tirosina Quinases/fisiologia , Receptores de Interleucina-2/fisiologia , Transdução de Sinais/fisiologia , Animais , Citoplasma/química , Ativação Enzimática , Regulação da Expressão Gênica/fisiologia , Humanos , Estrutura Terciária de Proteína
11.
J Exp Med ; 166(2): 607-12, 1987 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-3110357

RESUMO

AT11-2, an Abelson virus-transformed cell line has DJH complexes on both chromosomes and is able to form functional variable region genes by the joins of VH genes to the DJH complexes during culture. Therefore we examined which VH gene family was used in functional VH to DJH recombinations in AT11-2. Surprisingly, of 32 independent functional VH to DJH recombinational events in AT11-2, 31 events used the VH segments of the VHQ52 family, and the remaining one used the VH segment of the VH7183 family. Thus, we describe here the first B precursor cell line that almost selectively uses the VHQ52 family in functional VH to DJH rearrangements. The selective use of the VHQ52 family in this B precursor cell line strongly indicates nonrandom use of VH gene families, and the existence of a stage at which the VHQ52 family is preferentially used during the normal development of early pre-B cells and has important implications for understanding the ontogeny of VH repertoire development. Furthermore, this cell line should prove extremely valuable in further studies of this kind.


Assuntos
Linfócitos B/imunologia , Cadeias Pesadas de Imunoglobulinas/genética , Região Variável de Imunoglobulina/genética , Animais , Linhagem Celular , Transformação Celular Viral , Camundongos , Camundongos Endogâmicos BALB C , Recombinação Genética
12.
Br J Cancer ; 103(9): 1443-7, 2010 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-20842123

RESUMO

BACKGROUND: The role of adult weight change in breast cancer (BC) risk is unclear in Japanese women. METHODS: A total of 10,106 postmenopausal women aged 40-64 years (the Miyagi Cohort) were followed from 1990 to 2003, and 108 BC cases were identified. Hazard ratios (HRs) were estimated according to body mass index (BMI) at the current age and at the of age 20 years, and weight change since age 20 years. RESULTS: Higher current BMI was associated with an increased risk of BC (P for trend=0.02), whereas higher BMI at the age 20 years was inversely associated with this risk (P for trend=0.002). There was a significant association between weight change since age 20 years and BC risk (P for trend=0.0086). Compared with stable weight, HR was 0.35 for weight loss of 5 kg or more (P for weight loss trend=0.04) and 1.55 for weight gain of 12 kg or more (P for weight gain trend=0.05). CONCLUSION: Adiposity at younger and current age has differential effects on BC risk among postmenopausal women; weight gain in adulthood being associated with an increased, and weight loss with a decreased risk.


Assuntos
Adiposidade/fisiologia , Neoplasias da Mama/epidemiologia , Pós-Menopausa , Aumento de Peso , Redução de Peso , Adulto , Povo Asiático , Índice de Massa Corporal , Feminino , Humanos , Pessoa de Meia-Idade , Risco
13.
Eur J Clin Invest ; 39(5): 359-67, 2009 May.
Artigo em Inglês | MEDLINE | ID: mdl-19371267

RESUMO

BACKGROUND: Endothelial progenitor cells (EPCs) play an important role in the maintenance of vascular integrity. Lipid lowering therapy (LLT) with statins may contribute to biologically relevant activities including the proliferation of endothelial cells. The physiological role of microRNA (miR)-221/222, a newly discovered class of small RNA, is closely linked to the proliferation of endothelial cells. We therefore investigated whether LLT with statins might affect miR-221/222 expression in EPCs obtained from patients with coronary artery disease (CAD). MATERIALS AND METHODS: This study included 44 patients with stable CAD and 22 subjects without CAD (non-CAD). Patients with CAD were randomized to 12 months of LLT with atorvastatin (10 mg day(-1)) or pravastatin (10 mg day(-1)). EPCs were obtained from peripheral blood at baseline and after 12 months of statin therapy. Levels of miR-221/222 in EPCs were measured by real-time RT-PCR. RESULTS: Levels of miR-221/222 were significantly higher in the CAD group than in the non-CAD group (P < 0.01). Levels of miR-221/222 were weakly negatively correlated with EPC number in the CAD group. After 12 months of therapy, changes in lipid profiles were greater in the atorvastatin group than in the pravastatin group. LLT with atorvastatin markedly increased EPC numbers and decreased miR-221/222 levels (all P < 0.05), whereas LLT with pravastatin did not change EPC numbers or miR-221/222 levels. CONCLUSIONS: This study demonstrates that LLT with atorvastatin increases EPC numbers and decreases miR-221/222 levels in patients with CAD, possibly contributing to the beneficial effects of LLT with atorvastatin in this disorder.


Assuntos
Anticolesterolemiantes/uso terapêutico , Doença da Artéria Coronariana/tratamento farmacológico , Células Endoteliais/efeitos dos fármacos , MicroRNAs/efeitos dos fármacos , Células-Tronco/efeitos dos fármacos , Idoso , Atorvastatina , Células Endoteliais/metabolismo , Feminino , Ácidos Heptanoicos/uso terapêutico , Humanos , Masculino , MicroRNAs/metabolismo , Pessoa de Meia-Idade , Pravastatina/uso terapêutico , Estudos Prospectivos , Pirróis/uso terapêutico , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Método Simples-Cego , Estatística como Assunto , Células-Tronco/metabolismo
14.
Science ; 266(5187): 1045-7, 1994 Nov 11.
Artigo em Inglês | MEDLINE | ID: mdl-7973659

RESUMO

The interleukin-2 receptor (IL-2R) consists of three subunits: the IL-2R alpha, IL-2R beta, and IL-2R gamma chains, the last of which is also used in the receptors for IL-4, IL-7, and IL-9. Stimulation with IL-2 induces the tyrosine phosphorylation and activation of the Janus kinases Jak1 and Jak3. Jak1 and Jak3 were found to be selectively associated with the "serine-rich" region of IL-2R beta and the carboxyl-terminal region of IL-2R gamma, respectively. Both regions were necessary for IL-2 signaling. Furthermore, Jak3-negative fibroblasts expressing reconstituted IL-2R became responsive to IL-2 after the additional expression of Jak3 complementary DNA. Thus, activation of Jak1 and Jak3 may be a key event in IL-2 signaling.


Assuntos
Interleucina-2/farmacologia , Proteínas Tirosina Quinases/metabolismo , Receptores de Interleucina-2/metabolismo , Animais , Linhagem Celular , Ativação Enzimática , Humanos , Janus Quinase 1 , Janus Quinase 3 , Receptores de Interleucina-2/química , Proteínas Recombinantes de Fusão/metabolismo , Transdução de Sinais , Tirosina/metabolismo
15.
Oncogene ; 26(34): 5023-7, 2007 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-17311002

RESUMO

Mutations in the ERBB2 gene were recently found in approximately 2% of primary non-small cell lung cancer (NSCLC) specimens; however, little is known about the functional consequences and the relevance to responsiveness to targeted drugs for most of these mutations. Here, we show that the major lung cancer-derived ERBB2 mutants, including the most frequent mutation, A775insYVMA, lead to oncogenic transformation in a cellular assay. Murine cells transformed with these mutants were relatively resistant to the reversible epidermal growth factor receptor (EGFR) inhibitor erlotinib, resembling the resistant phenotype found in cells carrying the homologous mutations in exon 20 of EGFR. However, the same cells were highly sensitive to the irreversible dual-specificity EGFR/ERBB2 kinase inhibitor HKI-272, as were those overexpressing wild-type ERBB2. Finally, the NSCLC cell line, Calu-3, overexpressing wild-type ERBB2 owing to a high-level amplification of the ERBB2 gene were highly sensitive to HKI-272. These results provide a rationale for treatment of patients with ERBB2-mutant or ERBB2-amplified lung tumors with HKI-272.


Assuntos
Antineoplásicos/farmacologia , Carcinoma Pulmonar de Células não Pequenas/genética , Genes erbB-2 , Neoplasias Pulmonares/genética , Mutação , Inibidores de Proteínas Quinases/farmacologia , Quinolinas/farmacologia , Receptor ErbB-2/antagonistas & inibidores , Carcinoma Pulmonar de Células não Pequenas/enzimologia , Linhagem Celular Tumoral , Transformação Celular Neoplásica/genética , Receptores ErbB/antagonistas & inibidores , Amplificação de Genes , Humanos , Neoplasias Pulmonares/enzimologia
16.
Eur J Clin Invest ; 38(2): 97-105, 2008 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-18226043

RESUMO

BACKGROUND: Tumour necrosis factor-alpha (TNF-alpha) converting enzyme (TACE) plays an essential role in the TNF-alpha shedding process, which could affect the outcome of acute myocardial infarction (AMI). However, it remains unclear whether it originates from the ruptured plaque or represents a systemic process. This study analysed TACE-mediated TNF-alpha shedding at the site of ruptured plaques in AMI patients and compared them with a systemic mechanism. MATERIALS AND METHODS: The study included 60 patients with AMI who underwent percutaneous coronary intervention (PCI) and 21 patients with stable angina pectoris (SA). Local samples from the site of plaque were taken from AMI using aspiration catheter treatment. Systemic samples were also taken from the aorta in all patients with AMI and SA. RESULTS: Systemic levels of TACE and TNF-alpha were higher in AMI patients than in SA patients. In AMI patients, these levels were higher in local samples than in systemic samples. A positive correlation was seen between local TACE and TNF-alpha levels in AMI patients. Thrombus material removed from the ruptured plaque showed immunostainings of TACE and TNF-alpha in infiltrating macrophages. By six months follow-up study, local TACE levels remained the only significant independent predictors of adverse cardiac events in AMI patients. CONCLUSIONS: This study demonstrates that local expression of TACE is related to TNF-alpha shedding at the site of ruptured plaques in AMI patients. In addition, local TACE expression at the site of ruptured plaques may play an important role in poor outcomes in patients with AMI.


Assuntos
Proteínas ADAM/metabolismo , Infarto do Miocárdio/metabolismo , Proteínas ADAM/genética , Proteína ADAM17 , Doença Aguda , Idoso , Biomarcadores , Progressão da Doença , Feminino , Citometria de Fluxo , Humanos , Masculino , Pessoa de Meia-Idade , Monócitos/metabolismo , Análise de Regressão , Reação em Cadeia da Polimerase Via Transcriptase Reversa
17.
Cell Death Differ ; 13(7): 1170-80, 2006 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-16311512

RESUMO

The antioncogenic Chk2 kinase plays a crucial role in DNA damage-induced cell-cycle checkpoint regulation. Here we show that Chk2 associates with the oncogenic protein Wip1 (wild-type p53-inducible phosphatase 1) (PPM1D), a p53-inducible protein phosphatase. Phosphorylation of Chk2 at threonine68 (Thr68), a critical event for Chk2 activation, which is normally induced by DNA damage or overexpression of Chk2, is inhibited by expression of wild-type (WT), but not a phosphatase-deficient mutant (D314A) of Wip1 in cultured cells. Furthermore, an in vitro phosphatase assay revealed that Wip1 (WT), but not Wip1 (D314A), dephosphorylates Thr68 on phosphorylated Chk2 in vitro, resulting in the inhibition of Chk2 kinase activity toward glutathione S-transferase-Cdc25C. Moreover, inhibition of Wip1 expression by RNA interference results in abnormally sustained Thr68 phosphorylation of Chk2 and increased susceptibility of cells in response to DNA damage, indicating that Wip1 acts as a negative regulator of Chk2 in response to DNA damage.


Assuntos
Fosfoproteínas Fosfatases/metabolismo , Proteínas Serina-Treonina Quinases/metabolismo , Aminoácidos/metabolismo , Apoptose/fisiologia , Proteínas de Ciclo Celular/metabolismo , Linhagem Celular , Núcleo Celular/metabolismo , Quinase do Ponto de Checagem 2 , Dano ao DNA , Células HCT116 , Humanos , Immunoblotting , Mutação , Fosfoproteínas Fosfatases/genética , Fosforilação , Proteína Fosfatase 1 , Proteína Fosfatase 2C , RNA Interferente Pequeno/genética , Serina/metabolismo , Treonina/metabolismo , Proteínas Supressoras de Tumor/genética , Proteínas Supressoras de Tumor/metabolismo
18.
J Clin Invest ; 96(3): 1195-201, 1995 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-7657791

RESUMO

myo-inositol, a major compatible osmolyte in renal medulla, is accumulated in several kinds of cells under hypertonic conditions via Na+/myo-inositol cotransporter (SMIT). To investigate the physiological role of the SMIT, we sought to determine its localization by in situ hybridization and its acute regulation by NaCl and furosemide administration. Northern analysis demonstrated that SMIT is strongly expressed in the medulla and at low levels in the cortex of kidney. Intraperitoneal injection of NaCl rapidly induced SMIT mRNA in both the cortex and medulla, and furosemide completely abolished this induction. In situ hybridization revealed that SMIT it predominantly present in the medullary and cortical thick ascending limbs of Henle's loop (TALH) and macula densa cells. Less intense signals were seen in the inner medullary collecting ducts (IMCD). NaCl loading increased the signals throughout the TALH, and furosemide reduced the signals. SMIT in the IMCD is less sensitive to these kinds of acute regulation. Thus, the distribution pattern of SMIT does not correspond to the corticomedullary osmotic gradient, and SMIT in the TALH and macula densa cells is regulated very rapidly. These results suggest that SMIT expression in TALH may be regulated by intracellular and/or peritubular tonicity close to the basolateral membrane, which is supposed to be proportional to the magnitude of NaCl reabsorption.


Assuntos
Proteínas de Transporte/metabolismo , Expressão Gênica , Proteínas de Choque Térmico/metabolismo , Rim/metabolismo , Proteínas de Membrana , Simportadores , Animais , Sequência de Bases , Northern Blotting , Proteínas de Transporte/análise , Proteínas de Transporte/biossíntese , Primers do DNA , Furosemida/farmacologia , Expressão Gênica/efeitos dos fármacos , Proteínas de Choque Térmico/análise , Proteínas de Choque Térmico/biossíntese , Hibridização In Situ , Rim/efeitos dos fármacos , Córtex Renal/metabolismo , Medula Renal/metabolismo , Cinética , Masculino , Dados de Sequência Molecular , Sondas de Oligonucleotídeos , Especificidade de Órgãos , RNA Mensageiro/análise , RNA Mensageiro/biossíntese , Ratos , Ratos Wistar , Fatores de Tempo
19.
Mol Cell Biol ; 14(8): 5433-40, 1994 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-8035820

RESUMO

The high-affinity interleukin 2 receptor (IL-2R) consists of at least three distinct subunits: the IL-2R alpha chain (IL-2R alpha), beta chain (IL-2R beta), and gamma chain (IL-2R gamma). It has been shown that the cytoplasmic region of IL-2R beta, but not of IL-2R alpha, is essential for IL-2 signalling to the cell interior. In the present study, we examined the functional role of the IL-2R gamma cytoplasmic region in the IL-3-dependent mouse hematopoietic cell line BAF-B03, which expresses the endogenous IL-2R alpha and IL-2R gamma, or its subline F7, which additionally expresses human IL-2R beta cDNA. We show that overexpression of a mutant IL-2R gamma, lacking all but 7 amino acids of its cytoplasmic region, results in the selective inhibition of IL-2-induced c-fos gene activation and cellular proliferation in F7 cells. When two chimeric receptor molecules in which the cytoplasmic regions of IL-2R beta and IL-2R gamma had been swapped with each other (IL-2R beta/gamma and IL-2R gamma/beta) were coexpressed in BAF-B03, the cells responded to IL-2. These results indicate the critical importance of the IL-2-induced functional cooperation of the two cytoplasmic regions. Finally, we provide evidence that the IL-2R gamma cytoplasmic region is also critical for the IL-4 and IL-7-induced growth signal transduction in BAF-B03.


Assuntos
Interleucina-2/farmacologia , Interleucina-4/farmacologia , Interleucina-7/farmacologia , Receptores de Interleucina-2/química , Receptores de Interleucina/fisiologia , Receptores Mitogênicos/fisiologia , Animais , Divisão Celular , Linhagem Celular , Citoplasma/metabolismo , Regulação da Expressão Gênica , Genes fos , Genes myc , Camundongos , RNA Mensageiro/genética , Receptores de Interleucina-2/fisiologia , Receptores de Interleucina-4 , Receptores de Interleucina-7 , Transdução de Sinais , Ativação Transcricional
20.
Mol Cell Biol ; 14(2): 1459-64, 1994 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-8289821

RESUMO

The majority of mouse HSP90 exists as alpha-alpha and beta-beta homodimers. Truncation of the 15-kDa carboxy-terminal region of mouse HSP90 by digestion with the Ca(2+)-dependent protease m-calpain caused dissociation of the dimer. When expressed in a reticulocyte lysate, the full-length human HSP90 alpha formed a dimeric form. A plasmid harboring human HSP90 alpha cDNA was constructed so that the carboxy-terminal 49 amino acid residues were removed when translated in vitro. This carboxy-terminally truncated human HSP90 alpha was found to exist as a monomer. In contrast, loss of the 118 amino acid residues from the amino terminus of human HSP90 alpha did not affect its in vitro dimerization. Introduction of an expression plasmid harboring the full-length human HSP90 alpha complements the lethality caused by the double mutations of two HSP90-related genes, hsp82 and hsc82, in a haploid strain of Saccharomyces cerevisiae. The carboxy-terminally truncated human HSP90 alpha neither formed dimers in yeast cells nor rescued the lethal double mutant.


Assuntos
Proteínas de Choque Térmico/metabolismo , Sequência de Aminoácidos , Animais , Calpaína/isolamento & purificação , Calpaína/metabolismo , Proteínas de Choque Térmico/biossíntese , Proteínas de Choque Térmico/isolamento & purificação , Humanos , Leucemia L5178/metabolismo , Substâncias Macromoleculares , Mamíferos , Camundongos , Dados de Sequência Molecular , Músculos/enzimologia , Fragmentos de Peptídeos/química , Biossíntese de Proteínas , Coelhos , Mapeamento por Restrição , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/crescimento & desenvolvimento , Saccharomyces cerevisiae/metabolismo , Transcrição Gênica , Células Tumorais Cultivadas
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