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Spin-orbit coupling (SOC) is pivotal for various fundamental spin-dependent phenomena in solids and their technological applications. In semiconductors, these phenomena have been so far studied in relatively weak electron-electron interaction regimes, where the single electron picture holds. However, SOC can profoundly compete against Coulomb interaction, which could lead to the emergence of unconventional electronic phases. Since SOC depends on the electric field in the crystal including contributions of itinerant electrons, electron-electron interactions can modify this coupling. Here we demonstrate the emergence of the SOC effect in a high-mobility two-dimensional electron system in a simple band structure MgZnO/ZnO semiconductor. This electron system also features strong electron-electron interaction effects. By changing the carrier density with Mg-content, we tune the SOC strength and achieve its interplay with electron-electron interaction. These systems pave a way to emergent spintronic phenomena in strong electron correlation regimes and to the formation of quasiparticles with the electron spin strongly coupled to the density.
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The impact of electron correlation on the Dirac semimetal state is investigated for perovskite CaIrO_{3} in terms of the magnetotransport properties under varying pressures. The reduction of electron correlation with a pressure of 1 GPa enhances the Fermi velocity as much as 40%, but it reduces the mobility by an order of magnitude by detuning the Dirac node from the Fermi energy. Moreover, the giant magnetoresistance at the quantum limit due to the one-dimensional confinement of Dirac electrons is critically suppressed under pressure. These results indicate that the electron correlation is a crucial knob for controlling the transport of a correlated Dirac semimetal.
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Electrons in conventional metals become less mobile under the influence of electron correlation. Contrary to this empirical knowledge, we report here that electrons with the highest mobility ever found in known bulk oxide semiconductors emerge in the strong-correlation regime of the Dirac semimetal of perovskite CaIrO3. The transport measurements reveal that the high mobility exceeding 60,000 cm2V-1s-1 originates from the proximity of the Fermi energy to the Dirac node (ΔE < 10 meV). The calculation based on the density functional theory and the dynamical mean field theory reveals that the energy difference becomes smaller as the system approaches the Mott transition, highlighting a crucial role of correlation effects cooperating with the spin-orbit coupling. The correlation-induced self-tuning of Dirac node enables the quantum limit at a modest magnetic field with a giant magnetoresistance, thus providing an ideal platform to study the novel phenomena of correlated Dirac electron.
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Japanese herbal medicines have long been used as alternative therapy because of their immunomodulatory effects. In recent years, use herbal medicines is rapidly increasing worldwide. In this study, we investigated the effect of 17 components of traditional Japanese herbal medicines on alloimmune responses in a murine model of cardiac allograft transplantation. Fully vascularized heterotopic hearts from C57BL/6 donors were transplanted into CBA mice by using microsurgical techniques. Artemisiae capillaris herba (Inchinko) was given to CBA recipients at a dosage of 1 g/kg/day from the day of transplantation until 7 days afterward. The other 16 components were given at a dosage of 2 g/kg/day for the same time period. Naïve CBA mice rejected C57BL/6 cardiac grafts acutely (median survival time [MST] of 7 days). CBA transplant recipients given 2 g/kg/day of Glycyrrhizae radix (Kanzou), Poria sclerotium (Bukuryo), Pinellia tuber (Hange), Cnidii rhizome (Senkyu), Paeoniae radix (Shakuyaku), and Scutellariae radix (Ogon) had prolonged C57BL/6 allograft survival significantly (MSTs were 18, 18, 17, 14, 12, and 12 days, respectively). Moreover, CBA transplant recipients given 1g/kg/day of Artemisiae capillaris herba had prolonged C57BL/6 allograft survival (MST >100 days); however, none of other 10 components prolonged allograft survival. In conclusion, administration of 7 components of traditional Japanese herbal medicines might induce prolongation of fully major histocompatibility complex-mismatched cardiac allografts.
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Supervivencia de Injerto/efectos de los fármacos , Trasplante de Corazón , Corazón , Inmunosupresores/farmacología , Extractos Vegetales/farmacología , Plantas Medicinales , Aloinjertos/efectos de los fármacos , Animales , Corazón/efectos de los fármacos , Complejo Mayor de Histocompatibilidad/efectos de los fármacos , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Endogámicos CBA , Trasplante HomólogoRESUMEN
BACKGROUND AND PURPOSE: In patients with rheumatoid arthritis (RA), the serum C-reactive protein (CRP) level is associated with ischaemic cerebrovascular disease (iCVD). Acute iCVD patients with RA were investigated, assessing changes of clinical characteristics and CRP with progress in RA treatment. METHODS: Patients hospitalized for acute iCVD from August 2002 to February 2018 were divided into two groups at February 2010. Patients with RA were retrospectively identified. The incidence of RA, the occurrence of acute exacerbation of inflammation due to causes other than synovitis preceding iCVD (non-synovitis AEI) and serum CRP were compared. RESULTS: In the first and second periods, 23/1203 patients (1.9%) and 22/1094 patients (2.0%) respectively had acute iCVD with RA. Non-synovitis AEI was significantly less frequent in the second period (5%, n = 1) than in the first period (35%, n = 8) (P < 0.05). CRP was significantly lower at iCVD onset in the second period [median and interquartile range 2.72 (0.89-4.5) mg/dl vs. 0.34 (0.12-1.19) mg/dl, P < 0.01]. Excluding nine patients with non-synovitis AEI, CRP was still lower in the second period [1.21 (0.47-2.72) mg/dl vs. 0.33 (0.11-0.98) mg/dl, P < 0.01]. CRP levels before both iCVD and non-synovitis AEI tended to be lower in the second period [1.53 (0.3-2.78) mg/dl vs. 0.69 (0.06-1.28) mg/dl, P = 0.059]. Two patients using tocilizumab developed iCVD despite persistently low CRP levels. CONCLUSIONS: With progress in treatment, RA-related inflammation was better suppressed and CRP decreased, but the prevalence of RA amongst acute iCVD patients was unchanged. Strategies for tighter control of inflammation are needed, and a new biomarker may be required in patients using tocilizumab.
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Artritis Reumatoide/complicaciones , Isquemia Encefálica/etiología , Anciano , Anciano de 80 o más Años , Antiinflamatorios/uso terapéutico , Anticuerpos Monoclonales Humanizados/uso terapéutico , Artritis Reumatoide/sangre , Artritis Reumatoide/tratamiento farmacológico , Biomarcadores/sangre , Proteína C-Reactiva/análisis , Progresión de la Enfermedad , Femenino , Humanos , Masculino , Estudios RetrospectivosRESUMEN
BACKGROUND: Immunocomplex capture fluorescence analysis (ICFA) detects donor-specific antihuman leukocyte antigen (HLA) antibodies (DSA), but the detection sensitivity of HLA class II antibodies using conventional ICFA is as low as 57%. The aim of the study was to improve the detection sensitivity of HLA class II antibodies by ICFA, and compare the ICFA results with the Luminex single-antigen bead test. METHODS: Six DSA-negative kidney transplant donors and recipient pairs and 10 HLA class II DSA-positive pairs were included in the study. The detection sensitivity of modified ICFA was compared with conventional ICFA, and the ICFA results were compared with the Luminex single-antigen bead test. RESULTS: The index value of modified ICFA was higher than that of conventional ICFA. The cutoff value of conventional ICFA was 30,686 (MFI), which was improved to 19,405 using modified ICFA. Regarding the HLA-DQ antibody, 5 samples found to be positive by Luminex single-antigen bead testing were all negative using modified ICFA. The reason for this discrepancy could be related to: (1) the difference in detection sensitivity; (2) the difference in HLA antigen surface expression between naive lymphocytes and synthetic beads; or (3) the structure of synthetic HLA DQ antigen on the Luminex single-antigen beads. CONCLUSION: The index value of the modified ICFA was higher than that of conventional ICFA, and the detection sensitivity of HLA class II antibodies was improved by modified ICFA. Further assessment is necessary to clarify the reasons for divergence between ICFA and Luminex single-antigen bead test results.
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Antígenos de Histocompatibilidad Clase II/inmunología , Prueba de Histocompatibilidad/métodos , Inmunoensayo/métodos , Trasplante de Riñón , Adulto , Anticuerpos/inmunología , Femenino , Técnica del Anticuerpo Fluorescente/métodos , Rechazo de Injerto/inmunología , Humanos , Masculino , Persona de Mediana Edad , Donantes de TejidosRESUMEN
Quantum EXPRESSO is an integrated suite of open-source computer codes for quantum simulations of materials using state-of-the-art electronic-structure techniques, based on density-functional theory, density-functional perturbation theory, and many-body perturbation theory, within the plane-wave pseudopotential and projector-augmented-wave approaches. Quantum EXPRESSO owes its popularity to the wide variety of properties and processes it allows to simulate, to its performance on an increasingly broad array of hardware architectures, and to a community of researchers that rely on its capabilities as a core open-source development platform to implement their ideas. In this paper we describe recent extensions and improvements, covering new methodologies and property calculators, improved parallelization, code modularization, and extended interoperability both within the distribution and with external software.
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Antígenos CD/metabolismo , Crisis Blástica/metabolismo , Moléculas de Adhesión Celular/metabolismo , Regulación Leucémica de la Expresión Génica , Leucemia Mieloide Aguda/metabolismo , Proteínas de Fusión Oncogénica/metabolismo , Proteína FUS de Unión a ARN/metabolismo , Adolescente , Antígenos CD/genética , Crisis Blástica/genética , Moléculas de Adhesión Celular/genética , Preescolar , Proteínas Ligadas a GPI/genética , Proteínas Ligadas a GPI/metabolismo , Humanos , Leucemia Mieloide Aguda/genética , Masculino , Proteínas de Fusión Oncogénica/genética , Proteína FUS de Unión a ARN/genéticaRESUMEN
Yogurt is a nutrient-rich food and the beneficial effects of yogurt on both health and immunomodulatory effects are well documented. In this pilot study, we investigated the effects of commercially produced yogurt R-1 on alloimmune responses in a murine cardiac transplantation model. The R-1 is produced by Meiji Co., Ltd., and contains live and active lactic acid bacteria (lactobacillus bulgaricus OLL1073R-1) mainly. CBA (H2k) mice underwent transplantation of a C57BL/6 (H2b; B6) heart and received oral administration of 1 mL, 0.1 mL, and 0.01 mL of R-1 from the day of transplantation until 7 days afterward. Additionally, we prepared one group of CBA recipients given 1 mL of R-1 sterilized by microwave for 7 days. Histological and immunohistochemical studies were performed. Naïve CBA mice rejected B6 cardiac graft acutely (median survival time [MST]: 7 days). CBA recipients given of 1 mL of R-1 had significantly prolonged B6 allograft survival (MST, 27 days). However, other doses of 0.1 mL and 0.01 mL of R-1 did not prolonged allograft survival (MSTs, 9 days and 8.5 days, respectively). Also, CBA recipients administered microwaved R-1 had no prolongation of B6 allograft (MST, 9 days). Histological and immunohistochemical studies showed the cardiac allograft from R-1-exposed CBA recipients had preserved graft and vessel structure and the number of infiltrated CD4+, CD8+, and Foxp3+ cells in R-1-exposed CBA recipients increased, respectively. In conclusion, our findings imply that yogurt containing active lactic acid bacteria could change alloimmune responses partially and induce the prolongation of cardiac allograft survival via CD4+Foxp3+ regulatory cells.
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Linfocitos T CD4-Positivos/inmunología , Factores de Transcripción Forkhead/inmunología , Supervivencia de Injerto/fisiología , Trasplante de Corazón , Yogur , Fenómenos Fisiológicos Nutricionales de los Animales/inmunología , Animales , Complejo Mayor de Histocompatibilidad/inmunología , Ratones , Ratones Endogámicos C57BL , Ratones Endogámicos CBA , Proyectos PilotoRESUMEN
The axion insulator which may exhibit an exotic quantized magnetoelectric effect is one of the most interesting quantum phases predicted for the three-dimensional topological insulator (TI). The axion insulator state is expected to show up in magnetically doped TIs with magnetizations pointing inwards and outwards from the respective surfaces. Towards the realization of the axion insulator, we here engineered a TI heterostructure in which magnetic ions (Cr) are modulation-doped only in the vicinity of the top and bottom surfaces of the TI ((Bi,Sb)2Te3) film. A separation layer between the two magnetic layers weakens interlayer coupling between them, enabling the magnetization reversal of individual layers. We demonstrate the realization of the axion insulator by observing a zero Hall plateau (ZHP) (where both the Hall and longitudinal conductivity become zero) in the electric transport properties, excluding the other possible origins for the ZHP. The manifestation of the axion insulator can lead to a new stage of research on novel magnetoelectric responses in topological matter.
RESUMEN
Manipulating the spins of the topological surface states represents an essential step towards exploring the exotic quantum states emerging from the time reversal symmetry breaking via magnetic doping or external magnetic fields. The latter case relies on the Zeeman effect and thereby we need to estimate the g-factor of the topological surface state precisely. Here, we report the direct observations of the Zeeman effect at the surfaces of Bi2Se3 and Sb2Te2Se by spectroscopic-imaging scanning tunnelling microscopy. The Zeeman shift of the zero mode Landau level is identified unambiguously by appropriately excluding the extrinsic effects arising from the nonlinearity in the band dispersion of the topological surface state and the spatially varying potential. Surprisingly, the g-factors of the topological surface states in Bi2Se3 and Sb2Te2Se are very different (+18 and -6, respectively). Such remarkable material dependence opens up a new route to control the spins of the topological surface states.
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Ciprofloxacin-resistant shigellosis outbreaks among men who have sex with men (MSM) have not been reported in Asia. During 3 March to 6 May 2015, the Notifiable Disease Surveillance System detected nine non-imported Shigella sonnei infections among human immunodeficiency virus (HIV) -infected Taiwanese MSM. We conducted a molecular epidemiological investigation using a 1 : 5 matched case-control study and laboratory characterizations for the isolates. Of the nine patients, four reported engagement in oral-anal sex before illness onset. Shigellosis was associated with a syphilis report within 12 months (adjusted odds ratio (aOR) 8.6; 95% CI 1.05-70.3) and no HIV outpatient follow-up within 12 months (aOR 22.3; 95% CI 2.5-201). Shigella sonnei isolates from the nine patients were all ciprofloxacin-resistant and the resistance was associated with S83L and D87G mutations in gyrA and S80I mutation in parC. The nine outbreak isolates were discriminated into two closely related pulsed-field gel electrophoresis (PFGE) genotypes and seven 8-locus multilocus variable-number tandem repeat analysis (MLVA8) types that suggest multiple sources of infections for the outbreak and possible under-recognition of infection among Taiwanese MSM. The outbreak isolates were characterized to be variants of the intercontinentally transmitted SS18.1 clone, which falls into the globally prevalent phylogenetic sub-lineage IIIb. Inter-database pattern similarity searching indicated that the two PFGE genotypes had emerged in the USA and Japan. The epidemiological characteristics of this outbreak suggest roles of risky sexual behaviours or networks in S. sonnei transmission. We urge enhanced surveillance and risk-reduction interventions regionally against the interplay of HIV and shigellosis among MSM.
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Antibacterianos/farmacología , Ciprofloxacina/farmacología , Brotes de Enfermedades , Farmacorresistencia Bacteriana , Disentería Bacilar/epidemiología , Infecciones por VIH/complicaciones , Shigella sonnei/efectos de los fármacos , Adulto , Estudios de Casos y Controles , Girasa de ADN/genética , Topoisomerasa de ADN IV/genética , Transmisión de Enfermedad Infecciosa , Disentería Bacilar/microbiología , Disentería Bacilar/transmisión , Electroforesis en Gel de Campo Pulsado , Genotipo , Homosexualidad Masculina , Humanos , Masculino , Persona de Mediana Edad , Repeticiones de Minisatélite , Epidemiología Molecular , Tipificación Molecular , Mutación Missense , Taiwán/epidemiología , Adulto JovenRESUMEN
PURPOSE: The authors report on a rare case of maternal virilization during pregnancy caused by autosomal recessive P450 oxidore- ductase (POR) deficiency. MATERIALS AND METHODS: A 24-year-old primigravida developed a deepening voice and hirsutism in the second trimester. Prenatal ultrasonography failed to detect any fetal abnormality and fetal growth was normal. POR deficiency was suspected, but the mother declined fetal genetic testing. A female neonate was delivered by cesarean section at 41 weeks' gestation. RESULTS: The neonate had skeletal abnormalities. Mutational analysis of the POR gene demonstrated homozygosity for c.1370 G>A and p.R457H in the patient and heterozygosity in her parents. POR deficiency was confirmed in the neonate. CONCLUSION: POR deficiency should be suspected in cases of maternal virilization. Maternal urinary estriol, fetal magnetic resonance imaging, and parental genetic testing should be performed. Parental consent for fetal genetic testing should be sought to ensure prompt diagnosis and early treatment.
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Fenotipo del Síndrome de Antley-Bixler/fisiopatología , Complicaciones del Embarazo/fisiopatología , Virilismo/fisiopatología , Fenotipo del Síndrome de Antley-Bixler/complicaciones , Fenotipo del Síndrome de Antley-Bixler/genética , Clítoris/anomalías , Femenino , Pruebas Genéticas , Humanos , Recién Nacido , Mutación , Linaje , Embarazo , Complicaciones del Embarazo/genética , Segundo Trimestre del Embarazo , Ultrasonografía Prenatal , Virilismo/etiología , Virilismo/genética , Adulto JovenRESUMEN
BACKGROUND: Determinant factors of aerobic fitness have not been clearly demonstrated in individuals with brain injury. AIM: To investigate the relationship between aerobic fitness and gender, age, intensity and total duration of aerobic physical activity, and skewness of the frequency distribution of 6-h continuous heart rate values in a larger sample of adults with brain injury. DESIGN: Cross-sectional and correlative study. SETTING: Research laboratory setting. POPULATION: Thirteen adult women and 20 adult men with cerebral palsy or stroke participated in this study. METHOD: VO2max was estimated using the multistage submaximal cycle ergometer test. Heart rate was recorded continuously for 6 h on a weekday. Relationships between predicted VO2max and gender, age, intensity and total duration of aerobic physical activity, skewness of frequency distribution, and average heart rate over 6 h were determined. RESULTS: Significant differences were seen in predicted VO2max between genders (P < 0.05). Predicted VO2max correlated significantly only with the skewness of the frequency distribution of values for continuous heart rate (r = -0.53, P < 0.01). CONCLUSION AND CLINICAL REHABILITATION IMPACT: The results suggest that brief and frequent physical activity may also improve aerobic fitness in adults with brain injury.
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Parálisis Cerebral/fisiopatología , Tolerancia al Ejercicio/fisiología , Frecuencia Cardíaca/fisiología , Actividad Motora , Aptitud Física/fisiología , Accidente Cerebrovascular/fisiopatología , Adulto , Factores de Edad , Parálisis Cerebral/rehabilitación , Estudios Transversales , Femenino , Humanos , Masculino , Persona de Mediana Edad , Consumo de Oxígeno/fisiología , Factores Sexuales , Rehabilitación de Accidente CerebrovascularRESUMEN
BACKGROUND: The role of microchimerism found in the peripheral blood of renal transplant recipients remains a matter of debate. We assessed the frequency of microchimerism after kidney transplantation and examined its influence on clinical courses over a 12-month follow-up period. PATIENTS AND METHODS: Ten single-kidney recipients underwent microchimerism detection at 2 days, 2 weeks, and 1, 3, 6, and 12 months after transplantation, with mismatch human leukocyte antigen (HLA)-A, -B, and -C used as markers. RESULTS: Microchimerism was detected in 8 (80%) patients at 2 days after kidney transplantation. In 3 of those, microchimerism became negative within 3 months after transplantation, whereas it remained present for up to 12 months in 3 patients (33 %). There was 1 acute rejection episode in a patient in whom microchimerism became negative within 3 months. Protocol renal graft biopsy specimens obtained 3 months after transplantation revealed no acute cellular-mediated rejection (ACMR) or acute antibody-mediated rejection (AAMR) in the 5 patients positive for microchimerism at 3 months. CONCLUSIONS: Microchimerism was frequently detected after kidney transplantation. Microchimerism that remained for more than 3 months post-transplantation might be correlated with a lower incidence of rejection, thus its monitoring may help identify recipients with a low rejection risk.
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Biomarcadores/sangre , Quimerismo , Antígenos HLA/genética , Trasplante de Riñón , Adulto , Anciano , Femenino , Antígenos HLA/sangre , Humanos , Masculino , Persona de Mediana EdadRESUMEN
OBJECTIVES: A number of reports have shown that the efficacy of mycophenolate mofetil (MMF) is superior to that of azathioprine (AZP) for long-term kidney allograft survival. We conducted a retrospective single-center study to evaluate renal function more than 2 years after conversion from AZP to MMF in kidney transplant recipients several years after transplantation. METHODS: AZP was converted to MMF in 51 recipients at 17.0 ± 0.8 years after kidney transplantation who were followed up for more than 2 years after conversion. Estimated glomerular filtration rate (eGFR) was determined using the Formula of the Japanese Society of Nephrology. RESULTS: The eGFR was significantly greater at 1 year before conversion (41.72 ± 1.91 mL/min/1.73 m(2)) as compared with the day of conversion (39.04 ± 1.82 mL/min/1.73 m(2); P < .05). After conversion, eGFR plateaued to 39.30 ± 2.01 mL/min/1.73 m(2) at 1 year and 38.24 ± 2.42 mL/min/1.73 m(2) at 2 years after conversion. The average eGFR slopes were -2.96 ± 0.36 mL/min/1.73 m(2) per year for AZP and 1.22 ± 0.10 mL/min/1.73 m(2) per year for MMF (P < .0001). Cyclosporine (CSA) was reduced from 176 ± 9.3 to 165 ± 9.8 mg/d (P = .0394) after the switch, whereas the CSA trough level was increased from 77.3 ± 6.6 to 118 ± 9.8 ng/mL (P = .0017). Furthermore, the daily dose of tacrolimus (TAC) was decreased from 3.5 ± 0.3 to 3.1 ± 0.3 mg/d (P = .0083). CONCLUSIONS: Our findings demonstrated the safety of conversion from AZP to MMF even in the patients who underwent renal transplantation several years prior. In addition, these short-term results indicated the improvement in allograft function following conversion.
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Azatioprina/uso terapéutico , Supervivencia de Injerto , Inmunosupresores/uso terapéutico , Trasplante de Riñón , Ácido Micofenólico/análogos & derivados , Adolescente , Adulto , Niño , Femenino , Tasa de Filtración Glomerular , Humanos , Masculino , Persona de Mediana Edad , Ácido Micofenólico/uso terapéutico , Adulto JovenRESUMEN
Circadian rhythms are modulated in a variety of peripheral tissues including the prostate, in which the mesenchyme and epithelium cells are controlled under androgens. Here, we investigated the testosterone regulation of core clock genes such as Bmal1, Clock, Per2 and Nr1d1 under a deficient state of testosterone. In vivo studies showed that the Bmal1 mRNA expression in the prostates displayed a peak at ZT 20 and a trough at ZT 12. Both Bmal1 and Clock transcripts decreased after castration. Conversely, the expression of Per2 that is promoted by binding of Bmal1 and Clock heterodimers to the E-box, enhanced or did not decease at least within 1 week after castration. The clock gene transcripts were recovered to the intact levels, when 1 mg testosterone was administered daily for 5 days. Fluorescent immunohistochemical studies revealed the increased staining of caspase 3 in the epithelium and Per2 in both the mesenchyme and epithelium after 1-week castration. In the mesenchyme cells prepared from castrated rats, the Per2 oscillation was generated in response to dexamethasone. The circadian rhythms of Bmal1 and Nr1d1 transcripts were obviously antiphase in the cells. However, the mesenchyme cells displayed the different profiles in the presence or absence of testosterone; the amplitude of the first phase was significantly decreased by testosterone. Addition of testosterone significantly increased the transcripts of Bmal1, Clock and Casp3 in cultured cells, whereas the Per2 and Nr1d1 transcripts were significantly inhibited. Collectively, the present results demonstrated that Bmal1 and Clock, but not Per2 and Nr1d1, are down-regulated in mesenchyme cells by testosterone deficiency. In addition to the conservative interlocked transcriptional-translational feedback loop, it is strongly suggested that the prostate clock system is controlled under androgen.
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Relojes Circadianos/fisiología , Mesodermo/citología , Próstata/citología , Testosterona/farmacología , Factores de Transcripción ARNTL/genética , Andrógenos/metabolismo , Animales , Proteínas CLOCK/biosíntesis , Proteínas CLOCK/genética , Caspasa 3/metabolismo , Castración , Ritmo Circadiano , Dexametasona/farmacología , Regulación hacia Abajo , Epitelio/metabolismo , Glucocorticoides/farmacología , Masculino , Miembro 1 del Grupo D de la Subfamilia 1 de Receptores Nucleares/biosíntesis , Proteínas Circadianas Period/biosíntesis , Proteínas Circadianas Period/metabolismo , ARN Mensajero/biosíntesis , Ratas , Ratas WistarRESUMEN
The objective of this study was to investigate ethnic differences in the glyoxylate reductase/hydroxypyruvate reductase (GRHPR) gene in patients with primary hyperoxaluria type 2 (PH2). GRHPR was genotyped in Japanese patients with PH2 and all GRHPR mutations described to date were reviewed in terms of geographic and ethnic association. We identified a novel mutation, a two-nucleotide deletion (c.248_249delTG) in exon 3 creating a premature 'stop' at codon 91. Also, we found that the c.864_865delTG mutation was associated with the rs35891798 single-nucleotide polymorphism. The allelic frequencies of the c.103delG, c.494G>A, c.403_404+2 delAAGT, and c.864_865delTG mutations in PH2 patients were 37.8%, 15.6%, 10.0%, and 10.0%, respectively. All patients with the c.103delG mutation were Caucasian. Patients with the c.494G>A mutation and 78% (7/9) of those with the c.403_404+2 delAAGT mutation were from the Indian subcontinent, whereas those with the c.864_865delTG mutation were Chinese or Japanese. Molecular analysis of GRHPR of four Japanese PH2 patients identified a novel mutation (c.248_249delTG in exon 3). Caucasians with PH2 should be screened for the c.103delG mutation; patients from the Indian subcontinent for c.494G>A; and patients of East Asian origin (particularly) for c.864_865delTG. The prevalence of the latter mutation in PH2 patients from East Asia was 75.0%.
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Oxidorreductasas de Alcohol/genética , Hiperoxaluria Primaria/genética , Adulto , Pueblo Asiatico/genética , Niño , Preescolar , Etnicidad/genética , Femenino , Humanos , Hiperoxaluria Primaria/etiología , Lactante , Masculino , Mutación , Polimorfismo de Nucleótido Simple , Eliminación de Secuencia , Población Blanca/genéticaRESUMEN
SETTING: Mycobacterium tuberculosis is classified into six phylogenetic lineages, each of which can be divided into sublineages. Sublineages of the same lineage have phenotypic differences, including their capacity to cause disease (pathogenicity). OBJECTIVE: 1) To test the hypothesis that different sublineages of lineage 4, which causes most of the tuberculosis (TB) in the United States, have varying ability to cause secondary cases as determined by genotypic clustering, a proxy for pathogenicity; and 2) to determine if spoligotype and mycobacterial interspersed repetitive units (MIRU) typing could infer sublineage. DESIGN: We included TB cases caused by lineage 4 strains from our community-based study in San Francisco. Sublineage was determined by regions of difference. Genotypic clustering was determined by insertion sequence 6110 and polymorphic guanine-cytosine-rich sequence. Associations between sublineages and patient characteristics were evaluated with adjusted and unadjusted analyses. RESULTS: The most frequent sublineage was H37Rv-like. In the adjusted analysis, sublineage 183 was associated with clustering and homelessness. We found that strains from different sublineages had convergent spoligotype and MIRU types. CONCLUSIONS: Sublineage 183 is associated with genotypic clustering, evidence of its being more able to cause secondary cases than the other lineage 4 sublineages. This finding suggests that bacterial factors contribute to the pathogenesis of TB. Spoligotype and MIRU type cannot be used to infer sublineage.
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Epidemiología Molecular , Mycobacterium tuberculosis/genética , Tuberculosis/microbiología , Técnicas de Tipificación Bacteriana , Análisis por Conglomerados , Genotipo , Personas con Mala Vivienda , Humanos , Mycobacterium tuberculosis/aislamiento & purificación , Mycobacterium tuberculosis/patogenicidad , Filogenia , Polimorfismo Genético , San Francisco/epidemiología , Tuberculosis/epidemiologíaRESUMEN
The Gyro centrifugal pump developed as a totally implantable artificial heart was designed with a free impeller, in which the rotational shaft (male bearing) of the impeller was completely separated from the female bearing. For this type of pump, it is very important to keep the proper magnet balance (impeller-magnet and actuator-magnet) in order to prevent thrombus formation and/or bearing wear. When the magnet balance is not proper, the impeller is jerked down into the bottom bearing. On the other hand, if magnet balance is proper, the impeller lifted off the bottom of the pump housing within a certain range of pumping conditions. In this study, this floating phenomenon was investigated in detail. The floating phenomenon was proved by observation of the impeller behavior using a transparent acrylic pump. The impeller floating phenomenon was mapped on a pump performance curve. The impeller floating phenomenon is affected by the magnet-magnet coupling distance and rotational speed of the impeller. In order to keep the proper magnet balance and to maintain the impeller floating phenomenon at the driving condition of right and left pump, the magnet-magnet coupling distance was altered by a spacer which was installed between the pump and actuator. It became clear that the same pump could handle different conditions (right and left ventricular assist), by just changing the thickness of the spacer. When magnet balance is proper, the floating impeller phenomenon occurs automatically in response to the impeller rev. It is called "the dynamic RPM suspension".