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1.
Sci Rep ; 7: 45217, 2017 03 24.
Artigo em Inglês | MEDLINE | ID: mdl-28338062

RESUMO

We present the first experimental evidence for metallicity, superconductivity (SC) and the co-existence of charge density waves (CDW) in the quasi-one-dimensional material HfTe3. The existence of such phenomena is a typical characteristic of the transition metal chalcogenides however, without the application of hydrostatic pressure/chemical doping, it is rare for a material to exhibit the co-existence of both states. Materials such as HfTe3 can therefore provide us with a unique insight into the relationship between these multiple ordered states. By improving on the original synthesis conditions, we have successfully synthesised single phase HfTe3 and confirmed the resultant structure by performing Rietveld refinement. Using low temperature resistivity measurements, we provide the first experimental evidence of SC at ~1.4 K as well as a resistive anomaly indicative of a CDW formation at ~82 K. By the application of hydrostatic-pressure, the resistivity anomaly shifts to higher temperature. The results show that HfTe3 is a promising new material to help study the relationship between SC and CDW.

2.
J Bone Miner Metab ; 35(4): 385-395, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-27484436

RESUMO

The aim of this study was to investigate the efficacy of concurrent treatment with vitamin K2 and risedronate compared with treatment with risedronate alone in patients with osteoporosis and to explore subsets of patients for which concurrent treatment is particularly efficacious. Women with osteoporosis aged 65 years or older were recruited from 123 institutes in Japan and allocated to take either vitamin K2 (45 mg/day) and risedronate (2.5 mg/day or 17.5 mg/week) or risedronate (2.5 mg/day or 17.5 mg/week) alone. The primary end point was the incidence of any fracture (vertebral and nonvertebral). The secondary end points were bone mineral density, height, undercarboxylated osteocalcin concentration, quality of life, and safety. Over a 2-year follow-up, vertebral or nonvertebral fractures occurred in 117 or 22 sites respectively among 931 patients in the risedronate and vitamin K2 group and in 104 or 26 sites respectively among 943 patients in the risedronate alone group. The rates of any incident fracture were similar between the two groups (incidence rate ratio 1.074, 95 % confidence interval 0.811-1.422, p = 0.62), implying that the primary end point was not met. There were no differences in the degree of increase in bone mineral density between the two groups. Undercarboxylated osteocalcin concentration decreased from 5.81 ± 3.93 ng/mL to 2.59 ± 1.52 ng/mL at 6 months in the risedronate and vitamin K2 group, whereas the change in the risedronate alone group was minimal (from 5.96 ± 4.36 ng/mL to 4.05 ± 3.40 ng/mL at 6 months) (p < 0.01). The treatment discontinuation rate was higher in the risedronate and vitamin K2 group than in the risedronate alone group (10.0 % vs 6.7 %). No unknown adverse drug reactions were reported. In conclusion, concurrent treatment with vitamin K2 and risedronate was not efficacious compared with monotherapy with risedronate in terms of fracture prevention.


Assuntos
Osteoporose/tratamento farmacológico , Ácido Risedrônico/uso terapêutico , Vitamina K 2/uso terapêutico , Idoso , Conservadores da Densidade Óssea/efeitos adversos , Conservadores da Densidade Óssea/uso terapêutico , Quimioterapia Combinada , Determinação de Ponto Final , Feminino , Humanos , Incidência , Japão , Adesão à Medicação , Pessoa de Meia-Idade , Fraturas por Osteoporose/tratamento farmacológico , Fraturas por Osteoporose/epidemiologia , Qualidade de Vida , Ácido Risedrônico/efeitos adversos , Vitamina K 2/efeitos adversos
3.
J Bone Miner Metab ; 33(6): 642-50, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25300745

RESUMO

Assessment of vertebral fracture is critically important for the diagnosis and treatment of osteoporosis. This study aimed to clarify the effectiveness of the semiquantitative (SQ) method in the assessment of vertebral fractures in Japanese clinical practice. Forty-four physicians (seven experts and 37 nonexperts) assessed the spinal radiographs of 40 patients participating in the Adequate Treatment of Osteoporosis (A-TOP) Japanese Osteoporosis Intervention Trial (JOINT)-02 at the baseline, 12 months, and 24 months using the SQ method. The proportion of diagnosed fracture cases per spine was higher in the nonexpert group than in the expert group at each time point, and was especially high in the upper thoracic spine (T4-T6). The least mean squares spinal fracture index was significantly higher in the nonexpert group than in the expert group for all time points. The kappa statistics were also higher in the expert group than in the nonexpert group for all vertebral levels at all time points. Assessment of vertebral fractures using the SQ method tended to be overestimated by nonexpert physicians compared with the experts, with poor nonexpert interobserver reliability and well-matched expert interobserver reliability. Conscious efforts to avoid overestimation and to obtain higher reliability with the SQ method should be made to achieve more precise diagnoses and treatment of osteoporosis in Japanese clinical practice.


Assuntos
Médicos , Competência Profissional , Fraturas da Coluna Vertebral/diagnóstico por imagem , Seguimentos , Humanos , Japão , Radiografia
4.
J Bone Miner Metab ; 32(3): 298-304, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-23828145

RESUMO

Concurrent treatments with bisphosphonates and vitamin K are promising given that bisphosphonates possibly interfere with vitamin K activation. This is a prospective, multi-center, open-labeled, randomized trial of the efficacy of concurrent treatment with vitamin K2 and risedronate compared with risedronate alone and to explore subsets of patients for which concurrent treatment is particularly efficacious (trial identification number UMIN000000991). Inclusion criteria are women who meet the criteria for pharmacological therapy for osteoporosis, aged ≥65 years, have any of pre-specified risk factors, can walk unassisted, and are able to answer questionnaires. Exclusion criteria are prior warfarin use, secondary osteoporosis or non-osteoporotic metabolic bone diseases, contraindication for vitamin K2 and risedronate, hyper- or hypoparathyroidism, mental disorders, prevalent vertebral fracture at ≥6 sites, severe degenerative spinal deformation between T4 and L4, serious heart, liver, or kidney disease, or bisphosphonate use within the previous 6 months. Patients were recruited from 123 institutes between January 2008 and February 2010, and allocated to vitamin K2 (45 mg/day) and risedronate (2.5 mg/day or 17.5 mg/week) or risedronate alone (2.5 mg/day or 17.5 mg/week) groups. Primary endpoint is a vertebral or non-vertebral fracture. Secondary endpoints are bone mineral density, height, undercarboxylated osteocalcin, JOQOL, EQ-5D and safety. A sample size of 910 subjects per group and 2-year follow-up will provide 80 % power to detect 35 % risk reduction for fracture, with a two-sided significance level of 5 %. Subgroup analysis stratified to adjustment factors for random allocation, body mass index, 25-hydroxyvitamin D, estimated glomerular filtration rate, grade of vertebral fracture, JOQOL, EQ-5D, and co-morbidity is pre-specified.


Assuntos
Conservadores da Densidade Óssea/uso terapêutico , Ácido Etidrônico/análogos & derivados , Osteoporose/tratamento farmacológico , Vitamina K 2/uso terapêutico , Idoso , Índice de Massa Corporal , Densidade Óssea/efeitos dos fármacos , Ácido Etidrônico/uso terapêutico , Feminino , Taxa de Filtração Glomerular/efeitos dos fármacos , Humanos , Osteocalcina/metabolismo , Osteoporose/metabolismo , Estudos Prospectivos , Ácido Risedrônico , Fraturas da Coluna Vertebral/tratamento farmacológico , Fraturas da Coluna Vertebral/metabolismo , Vitamina D/análogos & derivados , Vitamina D/metabolismo
5.
Curr Med Res Opin ; 27(6): 1273-84, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21554143

RESUMO

OBJECTIVES: The authors conducted a randomized controlled trial to clarify the efficacy and safety of alendronate plus alfacalcidol versus alendronate alone in a clinical setting. RESEARCH DESIGN AND METHODS: Eligible patients were postmenopausal women with severe osteoporosis who were aged 70 years or older and had several risk factors for incident fractures. The primary endpoint was prevention of incident fractures, and the anti-fracture efficacy was evaluated in relation to the baseline serum 25(OH)D level. RESULTS: A total of 2164 patients were randomized to alendronate plus alfacalcidol (combination therapy) or alendronate alone (monotherapy). Although the overall difference in the incidence of vertebral fracture between the two groups was not significant, the combination therapy group had a significantly reduced risk of vertebral fractures after the first 6 months (HR, 0.53). In subgroup analyses, the combination therapy group was superior in the strata of number of prevalent vertebral fractures of ≥2 (HR, 0.51) and grade 3 of prevalent vertebral fractures (HR, 0.55). The rate of non-vertebral weight-bearing bone fractures was significantly lower in the combination therapy group than in the monotherapy group during the follow-up period (HR, 0.31). A lower baseline 25(OH)D level was associated with a higher incidence of non-vertebral weight-bearing bone fractures (HR, 3.42) despite alendronate use. Although one patient given the combination therapy had mild hypercalcemia, serious hypercalcemia and unknown adverse events were not encountered. Because of the limitations presented in this study, these results may not apply to female patients with longer than 2 years of treatments, and to male osteoporosis patients. CONCLUSIONS: The combination therapy was no more effective for overall vertebral fracture prevention. However, subgroup analysis has shown that it was more effective for fracture prevention in patients with severe vertebral deformity, multiple prevalent vertebral fractures, and for non-vertebral weight-bearing bone fracture prevention.


Assuntos
Alendronato/uso terapêutico , Conservadores da Densidade Óssea/uso terapêutico , Fraturas Ósseas/prevenção & controle , Hidroxicolecalciferóis/uso terapêutico , Osteoporose/prevenção & controle , Alendronato/administração & dosagem , Alendronato/efeitos adversos , Conservadores da Densidade Óssea/administração & dosagem , Conservadores da Densidade Óssea/efeitos adversos , Hidroxicolecalciferóis/administração & dosagem , Hidroxicolecalciferóis/efeitos adversos , Japão
6.
J Bone Miner Metab ; 29(1): 37-43, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-20461422

RESUMO

The aim of osteoporosis treatment is to prevent future fractures. Although concurrent treatment has been used very frequently for osteoporosis in clinical practice, there are no data on accurate and verified effectiveness of concurrent treatment for fracture prevention in patients with osteoporosis. To clarify the clinical usefulness of concurrent treatment, the Japan Osteoporosis Society has authorized the establishment of the A-TOP (Adequate Treatment of Osteoporosis) research group. The objective of this research is to establish a design for a clinical trial to prove whether concurrent treatment using both alfacalcidol (1-alpha-hydroxycholecalciferol) and alendronate is more effective as compared to treatment using alendronate alone in terms of fracture prevention. The present study was named JOINT (Japanese Osteoporosis Intervention Trial) and is based on a method using national, prospective, randomized, open-labeled, blinded endpoints focusing on postmenopausal osteoporosis with a high risk for fracture. The patients were mainly selected by practitioners and allocated randomly by a central registration system into two groups, of which one received 5 mg/day of alendronate alone, and the other received 1 µg/day of 1-alpha-hydroxycholecalciferol (alfacalcidol) in addition to the alendronate. The endpoints focused primarily on fracture prevention, and the patients' quality of life (QOL) and change in body height, as well as adherence and the adverse events of the treatments were evaluated secondarily. To obtain sufficient statistical power in the events during a 2-year observation period, the patients who are expected to have higher risk were selected to participate in this study, and it was decided that the final plan would involve 890 patients per group (two-sided alpha = 0.05, power = 0.8). Data collection began in November 2003. Correspondence regarding the registration of the investigator and the progress of the study was conducted through a web system from the Public Health Research Foundation to practitioners.


Assuntos
Alendronato/uso terapêutico , Conservadores da Densidade Óssea/uso terapêutico , Hidroxicolecalciferóis/uso terapêutico , Osteoporose/tratamento farmacológico , Absorciometria de Fóton , Idoso , Humanos , Japão , Fraturas por Osteoporose/prevenção & controle
7.
Nihon Rinsho ; 67(5): 1017-21, 2009 May.
Artigo em Japonês | MEDLINE | ID: mdl-19432126

RESUMO

A-TOP research consortium has been authorized at 2000 by the Japanese Society of Osteoporosis and assisted by Public Health Research Foundation in order to obtain the clinical evidences regarding osteoporosis treatment. Each clinical trial program was named as JOINT (Japanese Osteoporosis Intervention Trial), which was multi-center randomized open label trial and was registered into clinical trial registry. JOINT-02 was started at 2003 to confirm the effect of combination treatment of active vitamin D3 and alendronate in the prevention of osteoporotic bone fracture occurrence. This trial will be terminated at 2009 and the subsequent third clinical trial to obtain the evidence regarding the combination effects of risedronate and vitamin K2 as JOINT-03 project has been started from 2008. Each trial included around 2,000 participants mainly from practitioner and the registration of the cases in JOINT-02 has been finished within 3 years, suggesting that the participated practitioner would have sympathy with the research aims. The A-TOP research group would have carried out epidemiological studies regarding establishment of osteoporosis database (JOB study), which will contribute the additional knowledge of Japanese osteoporosis.


Assuntos
Conservadores da Densidade Óssea/administração & dosagem , Estudos Multicêntricos como Assunto , Osteoporose/tratamento farmacológico , Ensaios Clínicos Controlados Aleatórios como Assunto , Alendronato/administração & dosagem , Colecalciferol/administração & dosagem , Quimioterapia Combinada , Medicina Baseada em Evidências , Fraturas Ósseas/etiologia , Fraturas Ósseas/prevenção & controle , Fraturas Espontâneas/etiologia , Fraturas Espontâneas/prevenção & controle , Humanos , Japão , Osteoporose/complicações , Guias de Prática Clínica como Assunto , Sociedades Médicas , Vitamina K 2/administração & dosagem
9.
Clin Calcium ; 16(9): 1500-7, 2006 Sep.
Artigo em Japonês | MEDLINE | ID: mdl-16951475

RESUMO

In 2002, Adequate Treatment of Osteoporosis (A-TOP) Research Group was organized to obtain the evidence for treatment of osteoporosis in Japan. The group has designed and carried out an intervention trial plan, Japanese Osteoporosis Intervention Trial (JOINT)-02 to demonstrate the possible combination effect of alendronate plus active vitamin D(3). In this report, we summarize the past activity and the perspective of the future of the A-TOP research group.


Assuntos
Alendronato/uso terapêutico , Conservadores da Densidade Óssea/uso terapêutico , Colecalciferol/uso terapêutico , Osteoporose/terapia , Pesquisa , Sociedades Médicas/organização & administração , Ensaios Clínicos como Assunto , Quimioterapia Combinada , Medicina Baseada em Evidências , Humanos , Japão , Osteoporose/complicações , Guias de Prática Clínica como Assunto , Sociedades Médicas/tendências , Fraturas da Coluna Vertebral/etiologia , Fraturas da Coluna Vertebral/prevenção & controle
10.
J Comput Chem ; 23(14): 1337-46, 2002 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-12214316

RESUMO

We developed a novel parallel algorithm for large-scale Fock matrix calculation with small locally distributed memory architectures, and named it the "RT parallel algorithm." The RT parallel algorithm actively involves the concept of integral screening, which is indispensable for reduction of computing times with large-scale biological molecules. The primary characteristic of this algorithm is parallel efficiency, which is achieved by well-balanced reduction of both communicating and computing volume. Only the density matrix data necessary for Fock matrix calculations are communicated, and the data once communicated are reutilized for calculations as many times as possible. The RT parallel algorithm is a scalable method because required memory volume does not depend on the number of basis functions. This algorithm automatically includes a partial summing technique that is indispensable for maintaining computing accuracy, and can also include some conventional methods to reduce calculation times. In our analysis, the RT parallel algorithm had better performance than other methods for massively parallel processors. The RT parallel algorithm is most suitable for massively parallel and distributed Fock matrix calculations for large-scale biological molecules with more than thousands of basis functions.


Assuntos
Algoritmos , Modelos Teóricos , Técnicas de Química Combinatória , Simulação por Computador , Fatores de Tempo
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