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1.
Phys Rev Lett ; 128(9): 091302, 2022 Mar 04.
Artículo en Inglés | MEDLINE | ID: mdl-35302802

RESUMEN

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.
Artículo en Inglés | MEDLINE | ID: mdl-32302154

RESUMEN

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.
Artículo en Inglés | MEDLINE | ID: mdl-25036366

RESUMEN

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.


Asunto(s)
Recesión Económica/historia , Personalidad , Suicidio/tendencias , Adulto , Femenino , Conductas Relacionadas con la Salud , Historia del Siglo XX , Humanos , Japón , Masculino , Persona de Mediana Edad , Modelos de Riesgos Proporcionales , Estudios Prospectivos , Factores de Riesgo , Encuestas y Cuestionarios
4.
Int J Clin Pract ; 69(8): 820-8, 2015 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-25521285

RESUMEN

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.


Asunto(s)
Insuficiencia Cardíaca/fisiopatología , Ruidos Cardíacos/fisiología , Enfermedad Aguda , Anciano , Anciano de 80 o más Años , Biomarcadores/sangre , Presión Sanguínea/fisiología , Femenino , Insuficiencia Cardíaca/mortalidad , Frecuencia Cardíaca/fisiología , Mortalidad Hospitalaria , Humanos , Masculino , Persona de Mediana Edad , Análisis Multivariante , Valor Predictivo de las Pruebas , Pronóstico
5.
Cytopathology ; 26(6): 354-61, 2015 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-25376185

RESUMEN

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.


Asunto(s)
Proteínas 14-3-3/análisis , Adenocarcinoma/diagnóstico , Biomarcadores de Tumor/análisis , Exorribonucleasas/análisis , Neoplasias Pulmonares/diagnóstico , Proteínas de Neoplasias/análisis , Adenocarcinoma/química , Adenocarcinoma del Pulmón , Adulto , Anciano , Anciano de 80 o más Años , Líquido del Lavado Bronquioalveolar/química , Broncoscopía , Femenino , Humanos , Inmunohistoquímica/métodos , Neoplasias Pulmonares/química , Masculino , Persona de Mediana Edad , Prueba de Papanicolaou , Sensibilidad y Especificidad , Coloración y Etiquetado/métodos
6.
Phys Rev Lett ; 112(7): 071101, 2014 Feb 21.
Artículo en Inglés | MEDLINE | ID: mdl-24579585

RESUMEN

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.
Artículo en Inglés | MEDLINE | ID: mdl-24597265

RESUMEN

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.


Asunto(s)
Trastornos del Desarrollo Sexual 46, XX/etiología , Neoplasias Ováricas/complicaciones , Complicaciones Neoplásicas del Embarazo , Virilismo/complicaciones , Virilismo/diagnóstico , Trastornos del Desarrollo Sexual 46, XX/complicaciones , Adulto , Neoplasias Cerebelosas/complicaciones , Neoplasias Cerebelosas/patología , Neoplasias Cerebelosas/cirugía , Cesárea , Trastornos del Desarrollo Sexual , Femenino , Edad Gestacional , Humanos , Recien Nacido Prematuro , Luteoma/complicaciones , Imagen por Resonancia Magnética , Meduloblastoma/complicaciones , Meduloblastoma/patología , Meduloblastoma/cirugía , Neoplasias Ováricas/patología , Neoplasias Ováricas/cirugía , Embarazo , Testosterona/sangre
9.
Rev Sci Instrum ; 94(6)2023 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-37862532

RESUMEN

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.
Artículo en Inglés | MEDLINE | ID: mdl-7612266

RESUMEN

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.


Asunto(s)
Interleucina-2/fisiología , Proteínas Tirosina Quinasas/fisiología , Receptores de Interleucina-2/fisiología , Transducción de Señal/fisiología , Animales , Citoplasma/química , Activación Enzimática , Regulación de la Expresión Génica/fisiología , Humanos , Estructura Terciaria de Proteína
11.
J Exp Med ; 166(2): 607-12, 1987 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-3110357

RESUMEN

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.


Asunto(s)
Linfocitos B/inmunología , Cadenas Pesadas de Inmunoglobulina/genética , Región Variable de Inmunoglobulina/genética , Animales , Línea Celular , Transformación Celular Viral , Ratones , Ratones Endogámicos BALB C , Recombinación Genética
12.
Br J Cancer ; 103(9): 1443-7, 2010 Oct 26.
Artículo en Inglés | MEDLINE | ID: mdl-20842123

RESUMEN

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.


Asunto(s)
Adiposidad/fisiología , Neoplasias de la Mama/epidemiología , Posmenopausia , Aumento de Peso , Pérdida de Peso , Adulto , Pueblo Asiatico , Índice de Masa Corporal , Femenino , Humanos , Persona de Mediana Edad , Riesgo
13.
Eur J Clin Invest ; 39(5): 359-67, 2009 May.
Artículo en Inglés | MEDLINE | ID: mdl-19371267

RESUMEN

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.


Asunto(s)
Anticolesterolemiantes/uso terapéutico , Enfermedad de la Arteria Coronaria/tratamiento farmacológico , Células Endoteliales/efectos de los fármacos , MicroARNs/efectos de los fármacos , Células Madre/efectos de los fármacos , Anciano , Atorvastatina , Células Endoteliales/metabolismo , Femenino , Ácidos Heptanoicos/uso terapéutico , Humanos , Masculino , MicroARNs/metabolismo , Persona de Mediana Edad , Pravastatina/uso terapéutico , Estudios Prospectivos , Pirroles/uso terapéutico , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Método Simple Ciego , Estadística como Asunto , Células Madre/metabolismo
14.
Science ; 266(5187): 1045-7, 1994 Nov 11.
Artículo en Inglés | MEDLINE | ID: mdl-7973659

RESUMEN

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.


Asunto(s)
Interleucina-2/farmacología , Proteínas Tirosina Quinasas/metabolismo , Receptores de Interleucina-2/metabolismo , Animales , Línea Celular , Activación Enzimática , Humanos , Janus Quinasa 1 , Janus Quinasa 3 , Receptores de Interleucina-2/química , Proteínas Recombinantes de Fusión/metabolismo , Transducción de Señal , Tirosina/metabolismo
15.
Oncogene ; 26(34): 5023-7, 2007 Jul 26.
Artículo en Inglés | MEDLINE | ID: mdl-17311002

RESUMEN

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.


Asunto(s)
Antineoplásicos/farmacología , Carcinoma de Pulmón de Células no Pequeñas/genética , Genes erbB-2 , Neoplasias Pulmonares/genética , Mutación , Inhibidores de Proteínas Quinasas/farmacología , Quinolinas/farmacología , Receptor ErbB-2/antagonistas & inhibidores , Carcinoma de Pulmón de Células no Pequeñas/enzimología , Línea Celular Tumoral , Transformación Celular Neoplásica/genética , Receptores ErbB/antagonistas & inhibidores , Amplificación de Genes , Humanos , Neoplasias Pulmonares/enzimología
16.
Eur J Clin Invest ; 38(2): 97-105, 2008 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-18226043

RESUMEN

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.


Asunto(s)
Proteínas ADAM/metabolismo , Infarto del Miocardio/metabolismo , Proteínas ADAM/genética , Proteína ADAM17 , Enfermedad Aguda , Anciano , Biomarcadores , Progresión de la Enfermedad , Femenino , Citometría de Flujo , Humanos , Masculino , Persona de Mediana Edad , Monocitos/metabolismo , Análisis de Regresión , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa
17.
Cell Death Differ ; 13(7): 1170-80, 2006 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-16311512

RESUMEN

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.


Asunto(s)
Fosfoproteínas Fosfatasas/metabolismo , Proteínas Serina-Treonina Quinasas/metabolismo , Aminoácidos/metabolismo , Apoptosis/fisiología , Proteínas de Ciclo Celular/metabolismo , Línea Celular , Núcleo Celular/metabolismo , Quinasa de Punto de Control 2 , Daño del ADN , Células HCT116 , Humanos , Immunoblotting , Mutación , Fosfoproteínas Fosfatasas/genética , Fosforilación , Proteína Fosfatasa 1 , Proteína Fosfatasa 2C , ARN Interferente Pequeño/genética , Serina/metabolismo , Treonina/metabolismo , Proteínas Supresoras de Tumor/genética , Proteínas Supresoras de Tumor/metabolismo
18.
J Clin Invest ; 96(3): 1195-201, 1995 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-7657791

RESUMEN

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.


Asunto(s)
Proteínas Portadoras/metabolismo , Expresión Génica , Proteínas de Choque Térmico/metabolismo , Riñón/metabolismo , Proteínas de la Membrana , Simportadores , Animales , Secuencia de Bases , Northern Blotting , Proteínas Portadoras/análisis , Proteínas Portadoras/biosíntesis , Cartilla de ADN , Furosemida/farmacología , Expresión Génica/efectos de los fármacos , Proteínas de Choque Térmico/análisis , Proteínas de Choque Térmico/biosíntesis , Hibridación in Situ , Riñón/efectos de los fármacos , Corteza Renal/metabolismo , Médula Renal/metabolismo , Cinética , Masculino , Datos de Secuencia Molecular , Sondas de Oligonucleótidos , Especificidad de Órganos , ARN Mensajero/análisis , ARN Mensajero/biosíntesis , Ratas , Ratas Wistar , Factores de Tiempo
19.
Mol Cell Biol ; 14(8): 5433-40, 1994 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-8035820

RESUMEN

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.


Asunto(s)
Interleucina-2/farmacología , Interleucina-4/farmacología , Interleucina-7/farmacología , Receptores de Interleucina-2/química , Receptores de Interleucina/fisiología , Receptores Mitogénicos/fisiología , Animales , División Celular , Línea Celular , Citoplasma/metabolismo , Regulación de la Expresión Génica , Genes fos , Genes myc , Ratones , ARN Mensajero/genética , Receptores de Interleucina-2/fisiología , Receptores de Interleucina-4 , Receptores de Interleucina-7 , Transducción de Señal , Activación Transcripcional
20.
Mol Cell Biol ; 14(2): 1459-64, 1994 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-8289821

RESUMEN

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.


Asunto(s)
Proteínas de Choque Térmico/metabolismo , Secuencia de Aminoácidos , Animales , Calpaína/aislamiento & purificación , Calpaína/metabolismo , Proteínas de Choque Térmico/biosíntesis , Proteínas de Choque Térmico/aislamiento & purificación , Humanos , Leucemia L5178/metabolismo , Sustancias Macromoleculares , Mamíferos , Ratones , Datos de Secuencia Molecular , Músculos/enzimología , Fragmentos de Péptidos/química , Biosíntesis de Proteínas , Conejos , Mapeo Restrictivo , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/crecimiento & desarrollo , Saccharomyces cerevisiae/metabolismo , Transcripción Genética , Células Tumorales Cultivadas
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