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The honeycomb lattice is one of the simplest lattice structures. Electrons and spins on this simple lattice, however, often form exotic phases with non-trivial excitations. Massless Dirac fermions can emerge out of itinerant electrons, as demonstrated experimentally in graphene, and a topological quantum spin liquid with exotic quasiparticles can be realized in spin-1/2 magnets, as proposed theoretically in the Kitaev model. The quantum spin liquid is a long-sought exotic state of matter, in which interacting spins remain quantum-disordered without spontaneous symmetry breaking. The Kitaev model describes one example of a quantum spin liquid, and can be solved exactly by introducing two types of Majorana fermion. Realizing a Kitaev model in the laboratory, however, remains a challenge in materials science. Mott insulators with a honeycomb lattice of spin-orbital-entangled pseudospin-1/2 moments have been proposed, including the 5d-electron systems α-Na2IrO3 (ref. 5) and α-Li2IrO3 (ref. 6) and the 4d-electron system α-RuCl3 (ref. 7). However, these candidates were found to magnetically order rather than form a liquid at sufficiently low temperatures, owing to non-Kitaev interactions. Here we report a quantum-liquid state of pseudospin-1/2 moments in the 5d-electron honeycomb compound H3LiIr2O6. This iridate does not display magnetic ordering down to 0.05 kelvin, despite an interaction energy of about 100 kelvin. We observe signatures of low-energy fermionic excitations that originate from a small number of spin defects in the nuclear-magnetic-resonance relaxation and the specific heat. We therefore conclude that H3LiIr2O6 is a quantum spin liquid. This result opens the door to finding exotic quasiparticles in a strongly spin-orbit-coupled 5d-electron transition-metal oxide.
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BACKGROUND: Concomitant resection of the sciatic nerve along with a malignant tumor is no longer a contraindication for limb-sparing surgery, as most of these patients remain ambulatory. However, sciatic nerve reconstruction after sarcoma resection is not commonly performed. Restoration of nerve function can improve patient quality of life. We describe our experience with four patients who underwent sciatic nerve reconstruction using an ipsilateral common peroneal nerve graft at the time of sarcoma resection. METHODS: Because of the low chance of peroneal nerve recovery, the ipsilateral peroneal trunk was used as a graft to reconstruct the tibial trunk of the sciatic nerve. Two patients were men and two were women. Mean age was 45.3 years (range, 15-62). Mean sciatic nerve defect length was 9.4 cm (range, 8.5-12.0). Proximal thigh defects (three patients) were reconstructed with a double cable; the one patient with a distal thigh defect underwent single cable reconstruction. Mean operation time was 492 min (range, 428-682). RESULTS: Mean length of the harvested peroneal trunks was 21 cm (range, 11-26). Mean graft length was 11.9 cm (range, 11-13). Postoperative course was uneventful in all four patients. One patient died of sarcoma lung metastasis and could not be evaluated. Three patients were followed for more than 2 years. Two patients achieved British Medical Research Council grade 4 plantar flexion; the remaining patient achieved grade 5 plantar flexion and grade 4 toe flexion. Semmes-Weinstein monofilament sensory testing showed loss of protective sensation on the plantar surface in all three. Musculoskeletal Tumor Society scores at last follow-up were 60.0%, 70.0%, and 43.3%, respectively. CONCLUSIONS: Immediate sciatic nerve reconstruction using an ipsilateral common peroneal nerve graft avoids reconstruction delay and scar tissue formation, which is advantageous for nerve recovery. This technique may be considered when sciatic nerve resection is anticipated during sarcoma resection.
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Nervio Peroneo , Sarcoma , Masculino , Humanos , Femenino , Persona de Mediana Edad , Nervio Peroneo/cirugía , Calidad de Vida , Nervio Ciático/cirugía , Muslo , Sarcoma/cirugía , Resultado del TratamientoRESUMEN
This study investigated the long-term survival and incidence of secondary fractures after fragility hip fractures. The 5-year survival rate was 62%, and the mortality risk was seen in patients with GNRI < 92. The 5-year incidence of secondary fracture was 22%, which was significantly higher in patients with a BMI < 20. BACKGROUND: Malnutrition negatively influences the postoperative survival of patients with fragility hip fractures (FHFs); however, little is known about their association over the long term. OBJECTIVE: This study evaluated the ability of the geriatric nutritional risk index (GNRI) as a risk factor for long-term mortality after FHFs. METHODS: This study included 623 Japanese patients with FHFs over the age of 60 years. We prospectively collected data on admission and during hospitalization and assessed the patients' conditions after discharge through a questionnaire. We examined the long-term mortality and the incidence of secondary FHFs and assessed the prognostic factors. RESULTS: The mean observation period was 4.0 years (range 0-7 years). The average age at the time of admission was 82 years (range 60-101 years). The overall survival after FHFs (1 year, 91%; 5 years, 62%) and the incidence of secondary FHFs were high (1 year, 4%; 5 years, 22%). The multivariate Cox proportional hazard analysis revealed the risk factors for mortality as older age (hazard ratio [HR] 1.04), male sex (HR 1.96), lower GNRI score (HR 0.96), comorbidities (malignancy, HR 2.51; ischemic heart disease, HR 2.24; revised Hasegawa dementia scale ≤ 20, HR 1.64), no use of active vitamin D3 on admission (HR 0.46), and a lower Barthel index (BI) (on admission, HR 1.00; at discharge, HR 0.99). The GNRI scores were divided into four risk categories: major risk (GNRI, < 82), moderate risk (82-91), low risk (92-98), and no risk (> 98). Patients at major and moderate risks of GNRI had a significantly lower overall survival rate (p < 0.001). Lower body mass index (BMI) was also identified as a prognostic factor for secondary FHFs (HR 0.88 [p = 0.004]). CONCLUSIONS: We showed that older age, male sex, a lower GNRI score, comorbidities, and a lower BI are risk factors for mortality following FHFs. GNRI is a novel and simple predictor of long-term survival after FHFs.
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Fracturas de Cadera , Desnutrición , Humanos , Masculino , Anciano , Persona de Mediana Edad , Anciano de 80 o más Años , Evaluación Nutricional , Pronóstico , Desnutrición/complicaciones , Desnutrición/epidemiología , Fracturas de Cadera/etiología , Factores de Riesgo , Evaluación Geriátrica , Estado Nutricional , Estudios RetrospectivosRESUMEN
The differential cross sections of the Σ^{-}pâΛn reaction were measured accurately for the Σ^{-} momentum (p_{Σ}) ranging from 470 to 650 MeV/c at the J-PARC Hadron Experimental Facility. Precise angular information about the Σ^{-}pâΛn reaction was obtained for the first time by detecting approximately 100 reaction events at each angular step of Δcosθ=0.1. The obtained differential cross sections show a slightly forward-peaking structure in the measured momentum regions. The cross sections integrated for -0.7≤cosθ≤1.0 were obtained as 22.5±0.68 [statistical error(stat.)] ±0.65 [systematic error(syst.)] mb and 15.8±0.83(stat)±0.52(syst) mb for 470
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AIMS: This study aimed to investigate the effect of Bacillus subtilis var. natto on the susceptibility of the model host, Caenorhabditis elegans, to bacterial infection. METHODS AND RESULTS: Caenorhabditis elegans worms were fed with a standard food consisting of Escherichia coli OP50 strain (control) or B. subtilis (natto) during their larval stage. The worms were then infected with pathogenic bacteria. We analyzed their survival time and RNA sequencing-based transcriptome. Upon infection with Staphylococcus aureus and Enterococcus faecalis, the survival time of B. subtilis (natto)-fed worms was longer than that of the control. Transcriptome analyses showed upregulation of genes associated with innate immunity and defense response to gram-positive bacteria in B. subtilis (natto)-fed worms. CONCLUSIONS: Bacillus subtilis (natto) conferred an increased resistance of C. elegans to gram-positive bacteria. Our findings provided insights into the molecular mechanisms underlying B. subtilis (natto)-regulated host immunity and emphasized its probiotic properties for preventing and alleviating infections caused by gram-positive bacteria. SIGNIFICANCE AND IMPACT OF THE STUDY: To the best of our knowledge, this is the first study to show that B. subtilis (natto) confers specific resistance against gram-positive bacteria.
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Bacillus subtilis , Probióticos , Animales , Bacillus subtilis/genética , Caenorhabditis elegans/genética , Enterococcus faecalis/genética , Staphylococcus aureusRESUMEN
The first-order Fermi acceleration of electrons requires an injection of electrons into a mildly relativistic energy range. However, the mechanism of injection has remained a puzzle both in theory and observation. We present direct evidence for a novel stochastic shock drift acceleration theory for the injection obtained with Magnetospheric Multiscale observations at the Earth's bow shock. The theoretical model can explain electron acceleration to mildly relativistic energies at high-speed astrophysical shocks, which may provide a solution to the long-standing issue of electron injection.
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OBJECTIVE: The objective of this study was to evaluate the chronic damage associated with pregnancies before and after the diagnosis of systemic lupus erythematosus (SLE). METHODS: Using childbearing-aged female SLE patient data registered at the Okayama and Showa University Hospitals, a nested case-control analysis was performed to investigate the relationship between pregnancy and chronic damage using the Systemic Lupus International Collaborating Clinics/American College of Rheumatology Damage Index (SDI). RESULTS: Pregnancy occurred in 22 patients before and 13 patients after the diagnosis of SLE in 104 eligible patients. Live births occurred in 82% (33/40) and 50% (9/18) of the pregnancies before and after the diagnosis of SLE, respectively. After matching age and disease duration, 33 case patients with chronic damage (SDI ≥ 1) and 33 control patients without chronic damage (SDI = 0) were selected. Hypertension was more frequent in cases than in controls (48% vs. 24%, p = 0.041). Pregnancies before and after the diagnosis of SLE were comparable between cases and controls (before the diagnosis: nine case patients and eight control patients; after the diagnosis: three case patients and five control patients; p = 1.00). Even after adjusting for hypertension using multivariate analysis, the pregnancies before and after the diagnosis were not significant predictors for chronic damage (odds ratio = 1.48 (95% confidence interval 0.33-6.65)), p = 0.60 of the pregnancy before the diagnosis; odds ratio = 0.78 (95% confidence interval 0.13-4.74), p = 0.78 of the pregnancy after the diagnosis). CONCLUSION: Pregnancies, either before or after the diagnosis of SLE, did not show any differences in chronic damage. Our results help alleviate fears regarding childbearing in female patients with SLE and their families.
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Estado de Salud , Lupus Eritematoso Sistémico/fisiopatología , Complicaciones del Embarazo , Adulto , Estudios de Casos y Controles , Estudios Transversales , Femenino , Humanos , Japón , Modelos Logísticos , Lupus Eritematoso Sistémico/diagnóstico , Análisis Multivariante , Embarazo , Sistema de Registros , Índice de Severidad de la Enfermedad , Adulto JovenRESUMEN
BACKGROUND: Palmoplantar pustulosis (PPP) is a distinct, chronic skin disorder characterized by intraepidermal pustules on the palms and soles. It is hypothesized that microorganisms on the skin might induce the symptoms of PPP via inflammatory cell activation. However, the microbiota has not been studied in detail because of the assumption that the pustules in PPP are sterile. AIM: To elucidate the role of microorganisms in pathogenesis of PPP. METHODS: PCR analysis was performed of microbial DNA fragments in the pustules of patients with PPP. The sequence of the D1/D2 LSU 26s rRNA gene and that of the 16S rRNA gene was used for fungal and bacterial DNA detection, respectively. RESULTS: In total, 71 samples were carefully collected from the pustules of patients with PPP. Fungal DNA bands were detected in 68 samples, and fungi including Malassezia spp. were identified in 30 of 71 samples (42.3%). Malassezia restricta was the most frequently encountered fungus (14/71; 19.7%). However, bacterial DNA was not detected by the methods used. Furthermore, identical fungal DNA was not detected in the outer lid of the pustules, suggesting that the fungi detected within the pustule did not derive from contamination via the skin surface. CONCLUSIONS: In the present study, we demonstrated for the first time that certain pustules in patients with PPP contain fungal DNA fragments, especially those of Malassezia spp. Our findings provide new insights on the role of skin microbiota in the pathogenesis of PPP.
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ADN Bacteriano/aislamiento & purificación , ADN de Hongos/aislamiento & purificación , Malassezia/aislamiento & purificación , Psoriasis/microbiología , Acremonium/genética , Acremonium/aislamiento & purificación , Adulto , Anciano , Aspergillus/genética , Aspergillus/aislamiento & purificación , Cladosporium/genética , Cladosporium/aislamiento & purificación , Femenino , Humanos , Malassezia/genética , Masculino , Persona de Mediana Edad , Reacción en Cadena de la Polimerasa , Saccharomycetales/genéticaRESUMEN
BACKGROUND: With the increasing use of biological agents for the treatment of psoriasis, the numbers of patients with interstitial lung disease (ILD) associated with biologics have also increased. Many of these cases were associated with tumour necrosis factor (TNF)-α inhibitors, but cases associated with other families of biologics have also been reported in Japan. AIM: To analyse the background factors of patients who developed ILD, and to discuss better management of biological treatment. METHOD: We reviewed 246 patients with psoriasis who were treated with biological agents in our department to identify any pulmonary adverse events (AEs). Data on patients who developed ILD were extracted to analyse background factors, clinical type of psoriasis, time to onset of ILD, pre-existing ILD, smoking habit and prescribed drugs. RESULTS: Pulmonary AEs were seen in 22 cases, of which 11 were diagnosed as drug-induced ILD. The causative drugs were mainly TNF-α inhibitors, accounting for eight cases (six treated with infliximab, two with adalimumab). The remaining three cases were associated with secukinumab, ustekinumab and ixekizumab (n = 1 each). Notably, these three cases also had a history of drug-induced ILD. CONCLUSION: Patients with a history of drug-induced ILD seem to be more susceptible to developing another ILD induced by biologics, even if treated with interleukin-17 inhibitors. Thorough screening of risk factors and evaluation for eligibility, and careful monitoring during treatment are the best solutions to avoid serious pulmonary AE. Early detection and precise diagnosis of pulmonary AEs, especially differentiation from infectious diseases, is essential for managing biological treatment.
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Factores Biológicos/efectos adversos , Enfermedades Pulmonares Intersticiales/inducido químicamente , Psoriasis/tratamiento farmacológico , Inhibidores del Factor de Necrosis Tumoral/efectos adversos , Adalimumab/efectos adversos , Adulto , Anciano , Anticuerpos Monoclonales Humanizados/efectos adversos , Antirreumáticos/efectos adversos , Factores Biológicos/uso terapéutico , Diagnóstico Precoz , Femenino , Humanos , Infliximab/efectos adversos , Japón/epidemiología , Enfermedades Pulmonares Intersticiales/epidemiología , Enfermedades Pulmonares Intersticiales/prevención & control , Masculino , Persona de Mediana Edad , Mucina-1/sangre , Psoriasis/complicaciones , Psoriasis/patología , Factores de Riesgo , Ustekinumab/efectos adversosRESUMEN
BACKGROUND: Transanal minimally invasive surgery is a combination of single-port surgery and transanal surgery and was initially developed as a treatment for rectal tumors. Recently, this approach has also been used for more advanced or extended pelvic surgery. METHODS: We present a surgical video of combined laparoscopic and transperineal endoscopic total pelvic exenteration performed in a male patient with recurrent rectal cancer and discuss the pros and cons of this approach. RESULTS: The operating time was 775 min and the operative blood loss was 485 ml. The pathology was recurrent adenocarcinoma invading the prostate and urethra with negative surgical margins. The postoperative course was uneventful except for a urinary tract infection that was treated with antibiotics. CONCLUSIONS: The transanal/perineal endoscopic approach may have some benefits for extended pelvic surgery for recurrent rectal cancer.
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Laparoscopía , Exenteración Pélvica , Neoplasias del Recto , Cirugía Endoscópica Transanal , Humanos , Masculino , Recurrencia Local de Neoplasia/cirugía , Neoplasias del Recto/cirugíaRESUMEN
Background: We assessed the non-inferiority of accelerated fractionation (AF) (2.4 Gy/fraction) compared with standard fractionation (SF) (2 Gy/fraction) regarding progression-free survival (PFS) in patients with T1-2N0M0 glottic cancer (GC). Patients and methods: In this multi-institutional, randomized, phase III trial, patients were enrolled from 32 Japanese institutions. Key inclusion criteria were GC T1-2N0M0, age 20-80, Eastern Cooperative Oncology Group performance status of 0-1, and adequate organ function. Patients were randomly assigned to receive either SF of 66-70 Gy (33-35 fractions), or AF of 60-64.8 Gy (25-27 fractions). The primary end point was the proportion of 3-year PFS. The planned sample size was 360 with a non-inferiority margin of 5%. Results: Between 2007 and 2013, 370 patients were randomized (184/186 to SF/AF). Three-year PFS was 79.9% (95% confidence interval [CI] 73.4-85.4) for SF and 81.7% (95% CI 75.4-87.0) for AF (difference 1.8%, 91% CI-5.1% to 8.8%; one-sided P = 0.047 > 0.045). The cumulative incidences of local failure at 3 years for SF/AF were 15.9%/10.3%. No significant difference was observed in 3-year overall survival (OS) between SF and AF. Grade 3 or 4 acute and late toxicities developed in 22 (12.4%)/21 (11.5%) and 2 (1.1%)/1 (0.5%) in the SF/AF arms. Conclusion: Although the non-inferiority of AF was not confirmed statistically, the similar efficacy and toxicity of AF compared with SF, as well as the practical convenience of its fewer treatment sessions, suggest the potential of AF as a treatment option for early GC. Clinical trials registration: UMIN Clinical Trial Registry, number UMIN000000819.
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Carcinoma de Células Escamosas/radioterapia , Glotis/patología , Neoplasias Laríngeas/radioterapia , Radioterapia/métodos , Adulto , Anciano , Anciano de 80 o más Años , Carcinoma de Células Escamosas/patología , Progresión de la Enfermedad , Fraccionamiento de la Dosis de Radiación , Femenino , Humanos , Neoplasias Laríngeas/patología , Masculino , Persona de Mediana Edad , Adulto JovenRESUMEN
We present a case of a woman with systemic lupus erythematosus (SLE) who had refractory episodes of neuromyelitis optica spectrum disorder (NMOSD) and was successfully treated with rituximab. She was positive for anti-aquaporin-4 (AQP4) antibody and had typical cranial and longitudinally extended spinal lesions but no optic nerve involvement. There is no established treatment for NMOSD/SLE overlap cases. Our experience suggests that rituximab may be effective for patients with combined SLE and anti-AQP4 antibody-positive NMOSD.
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Autoanticuerpos/sangre , Lupus Eritematoso Sistémico/complicaciones , Neuromielitis Óptica/tratamiento farmacológico , Rituximab/uso terapéutico , Acuaporina 4/inmunología , Femenino , Humanos , Imagen por Resonancia Magnética , Neuromielitis Óptica/complicaciones , Resultado del Tratamiento , Adulto JovenRESUMEN
OBJECTIVE: Serologically active clinically quiescent (SACQ)-SLE is a subtype of systemic lupus erythematosus (SLE); most SACQ-SLE patients relapse. Although complement and/or anti-dsDNA level fluctuations during SACQ status are reportedly not useful for predicting relapse, they might be useful in specific clinical settings. We aimed to assess the correlation between future relapse and progressive reductions in serum complement levels following remission in patients with hypocomplementemia . METHODS: We retrospectively reviewed patients aged ≥15 years who were treated with ≥20 mg/day of prednisolone for remission induction. After achieving remission, the patients treated with prednisolone tapered to ≤15 mg/day without relapse and followed by hypocomplementemia (first hypocomplementemia point) were analyzed. The primary outcome was the relapse during the first 24 months. RESULTS: Seventy-six patients were enrolled; 31 (40.8%) relapsed. A ≥10% reduction after the first hypocomplementemia point in serum C3, C4, and CH50 levels was found in 10, 21, and 16 patients, respectively. Hazard ratios (95% confidence intervals) for relapse were 2.32 (0.92-5.12) for serum C3 levels and 2.46 (1.18-5.01) for serum C4 levels. Progressive reductions in serum C3 and C4 levels had relatively high specificity (93.3% and 82.2%) but limited sensitivity (22.6% and 41.9%) for predicting relapse. However, simultaneous progressive reduction in C3 levels and increase in anti-dsDNA antibody levels had the highest specificity (97.8%), and simultaneous progressive reduction in C4 levels or increase in anti-dsDNA antibody levels had the highest sensitivity (71.0%). CONCLUSION: Simultaneous progressive reductions in complement levels and increases in anti-dsDNA antibody levels may indicate future relapse SACQ-SLE patients.
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Anticuerpos Antinucleares/sangre , Complemento C3/análisis , Complemento C4/análisis , Lupus Eritematoso Sistémico/sangre , Adulto , Femenino , Humanos , Lupus Eritematoso Sistémico/inmunología , Masculino , Persona de Mediana Edad , Recurrencia , Estudios Retrospectivos , Factores de Riesgo , Sensibilidad y Especificidad , Índice de Severidad de la Enfermedad , Adulto JovenRESUMEN
OBJECTIVE: Rheumatoid arthritis (RA) is a disease that typically induces secondary osteoporosis, which increases the risk of bone fractures. Anti-interleukin-6 (IL-6) receptor antibody is used to treat RA; however, its effect on bone strength is not clear. Therefore, we investigated the influence of MR16-1, an anti-mouse IL-6 receptor antibody, on bone structure and femoral strength in a collagen-induced arthritis (CIA) mouse model. METHOD: DBA/1J mice were immunized by intradermal injection of bovine type II collagen. MR16-1 was administered intraperitoneally at the same time as immunization. Thirty-five days after the first immunization, bone structure and bone strength were measured by micro-computed tomography and the three-point bending test. RESULTS: In the CIA group, most bone mineral density and bone structure parameters in the foot, femur, and lumbar spine were significantly lower than in the normal group. Moreover, the maximum load of the femoral shaft in the CIA group was significantly lower than in the normal group. MR16-1 treatment significantly prevented the CIA-induced deterioration of bone structure and loss of bone strength. CONCLUSION: These results suggest that CIA systemically induces a deterioration of bone structure and loss of bone strength, and that IL-6 signalling plays an important role in these processes.
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Anticuerpos Monoclonales/farmacología , Artritis Experimental/tratamiento farmacológico , Huesos/efectos de los fármacos , Osteoporosis/etiología , Receptores de Interleucina-6/antagonistas & inhibidores , Animales , Artritis Experimental/complicaciones , Densidad Ósea/efectos de los fármacos , Masculino , Ratones , Ratones Endogámicos DBA , Osteoporosis/tratamiento farmacológico , Microtomografía por Rayos XRESUMEN
This study was designed to investigate ethnic differences in the pharmacokinetics (PKs) of moxifloxacin and its metabolites, M1 (sulfo conjugate) and M2 (acyl-glucuronate), among Japanese, Chinese, and Korean populations, following oral administration. We used a population PK modeling approach using data from a clinical study involving 79 healthy male volunteers. A comprehensive population PK model considering the PK mechanism of moxifloxacin and its metabolites was newly built. The structures of the final model were two-compartment for moxifloxacin and one-compartment for M1 and M2, with first-order absorption with lag time for all three compounds. The formation of M1 and M2 from moxifloxacin via a first-pass effect and subsequent metabolic clearance in the system were also modeled. Lean body mass on the central volume of distribution (V c ) and estimated glomerular filtration rate on renal clearance (CL r ) were identified as covariates of PKs of moxifloxacin. Additionally, bioavailability was slightly higher in Koreans, whereas CL r , non-renal clearance (CL nr ), and V c were slightly lower. Regarding M1 and M2, body surface area on CL r of M2 and UGT1A1*6 on F of M2 were modeled. Korean ethnicity was observed to influence CL nr of M2, F of M2, and the metabolic clearance of moxifloxacin to M2. However, the exposure levels of moxifloxacin, M1, and M2 in Koreans were comparable to those in Japanese and Chinese because the effects of Korean ethnicity on some PK parameters were counterbalanced. These results suggest that PKs for moxifloxacin and its metabolites among East Asian populations are essentially similar.
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Moxifloxacino/farmacocinética , Administración Oral , Adulto , Pueblo Asiatico , Disponibilidad Biológica , Etnicidad , Tasa de Filtración Glomerular/fisiología , Glucuronosiltransferasa/metabolismo , Voluntarios Sanos , Humanos , Riñón/metabolismo , Masculino , Tasa de Depuración Metabólica/fisiología , Adulto JovenRESUMEN
A distinct thermal Hall signal is observed in a quantum spin liquid candidate Ba_{3}CuSb_{2}O_{9}. The transverse thermal conductivity shows a power-law temperature dependence below 50 K, where a spin gap opens. We suggest that because of the very low longitudinal thermal conductivity and the thermal Hall signals, a phonon Hall effect is induced by strong phonon scattering of orphan Cu^{2+} spins formed in the random domains of the Cu^{2+}-Sb^{5+} dumbbells in Ba_{3}CuSb_{2}O_{9}.
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Esophageal squamous cell carcinoma is a highly aggressive neoplasm and the sixth leading cause of global cancer-related death; the 5-year survival rate for esophageal cancer is only about 20%-25% for all stages. Therefore, improving the therapeutic effect is important. This study assessed whether low-dose hyperthermia (LDH) enhances the antitumor effects of chemotherapy. The antitumor effect of chemotherapy with/without LDH in the squamous cell carcinoma cell line SCCVII was evaluated. A comprehensive analysis was performed with real-time polymerase chain reaction (PCR) to study the hyperthermia-induced changes in the gene expression of SCCVII cell lines. In addition, the cytotoxic and apoptotic changes in the cells treated with LDH combined with/without 5-fluorouracil (5-FU) were measured. LDH combined with 5-FU (10 nM) strongly inhibited the cell growth of SCCVII, with flow cytometry showing an increased population of apoptotic cells. PCR showed that LDH promoted a 25.22-fold increase of p53 mRNA and 18.08-fold increase of Bax mRNA in vitro. MDR1 expression was decreased to 28.7% after LDH. This treatment can result in much higher efficacy of antitumor drugs. After LDH, the expressions of TS decreased to 12.06%, OPRT increased by 4.17-fold, and DPD did not change (1.03-fold). This transformations will induce susceptibility to 5-FU. LDH may be a useful enhancer of chemotherapy drugs for squamous cell carcinoma.
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Antimetabolitos Antineoplásicos/farmacología , Carcinoma de Células Escamosas/terapia , Neoplasias Esofágicas/terapia , Fluorouracilo/farmacología , Expresión Génica , Hipertermia Inducida , Subfamilia B de Transportador de Casetes de Unión a ATP/genética , Apoptosis/efectos de los fármacos , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Terapia Combinada , Dihidrouracilo Deshidrogenasa (NADP)/genética , Expresión Génica/efectos de los fármacos , Humanos , Orotato Fosforribosiltransferasa/genética , ARN Mensajero/metabolismo , Timidilato Sintasa/genética , Proteína p53 Supresora de Tumor/genética , Proteína X Asociada a bcl-2/genéticaRESUMEN
In vitro studies have shown that multidrug resistance protein 1 (MDR1) has an affinity for cortisol; however, in vivo association studies on the relationship between MDR1 gene polymorphisms and blood cortisol levels have produced inconsistent results. Therefore, we examined the effects of the C3435T polymorphism of the MDR1 gene on blood levels of hypothalamus-pituitary-adrenal (HPA) axis hormones such as cortisol and adrenocorticotropic hormone (ACTH) in healthy subjects. The subjects comprised 30 healthy Japanese males. Ten subjects were recruited for each of the C3435T MDR1 genotypes: C/C, C/T, and T/T. Blood samples were taken at 6:00 pm on two occasions with an interval of 2 weeks. Blood levels of cortisol and ACTH were determined by an electrochemiluminescence immunoassay. There were no significant differences in the blood levels of the HPA axis hormones among the MDR1 genotypes. The present study suggests that the C3435T MDR1 polymorphism does not affect blood levels of HPA axis hormones in healthy Japanese males.
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Sistema Hipotálamo-Hipofisario/metabolismo , Sistema Hipófiso-Suprarrenal/metabolismo , Subfamilia B de Transportador de Casetes de Unión a ATP/genética , Subfamilia B de Transportador de Casetes de Unión a ATP/metabolismo , Hormona Adrenocorticotrópica/sangre , Adulto , Alelos , Frecuencia de los Genes , Genotipo , Voluntarios Sanos , Humanos , Hidrocortisona/sangre , Japón , Masculino , Polimorfismo de Nucleótido SimpleRESUMEN
BACKGROUND: In the vitrification of embryos, dimethyl sulfoxide (DMSO) is one of the most effective cryoprotectant agents (CPAs), but cytotoxic effects of DMSO on embryos are well known. Carboxylated poly-L-lysine (CPLL) has been identified as an effective cryoprotectant of cultured cell lines and mammalian oocytes. OBJECTIVE: To evaluate the efficacy and safety of CPLL as a CPA for developmental stage embryos. MATERIALS AND METHODS: Mouse 8-cell embryos and blastocysts were vitrified with ethylene glycol (EG), DMSO/EG, or CPLL/EG and the developmental potency assessed in vitro. RESULTS: In 8-cell embryos, there were no differences between the levels of survival and developmental progress into the blastocyst stage in each solution. At the blastocyst stage, the proportion of dead cells was significantly higher in the EG compared with other solutions. In contrast, there were no differences between the DMSO/EG and CPLL/EG. CONCLUSION: These results indicate that CPLL can be used as a replacement for DMSO in the vitrification of mouse embryos.
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Blastocisto/efectos de los fármacos , Criopreservación/métodos , Crioprotectores/farmacología , Desarrollo Embrionario/efectos de los fármacos , Polilisina/farmacología , Animales , Dimetilsulfóxido/farmacología , Glicol de Etileno/farmacología , Femenino , Ratones , Oocitos/efectos de los fármacos , VitrificaciónRESUMEN
We report ac susceptibility, specific heat, and neutron scattering measurements on a dipolar-coupled antiferromagnet LiYbF_{4}. For the thermal transition, the order-parameter critical exponent is found to be 0.20(1) and the specific-heat critical exponent -0.25(1). The exponents agree with the 2D XY/h_{4} universality class despite the lack of apparent two-dimensionality in the structure. The order-parameter exponent for the quantum phase transitions is found to be 0.35(1) corresponding to (2+1)D. These results are in line with those found for LiErF_{4} which has the same crystal structure, but largely different T_{N}, crystal field environment and hyperfine interactions. Our results therefore experimentally establish that the dimensional reduction is universal to quantum dipolar antiferromagnets on a distorted diamond lattice.