Titanium migration driven by Li vacancies in Li(1-x)Ti2O4 spinel.

Gentle oxidation of lithium titanate spinel (LiTi2O4) with water at room temperature gives Li-deficient Li0.33Ti2O4. Combined X-ray and neutron Rietveld analysis shows that 28% of the Ti cations are displaced to alternative octahedral sites, in keeping with a proposed model based on Ti-migration limited by Li-vacancy concentration.

Comparative clinical and radiographic study of the lumbar spine between parachute infantry soldiers and non-parachute infantry soldiers in Japanese Ground Self-Defense forces.

BACKGROUND: The long-term effect of repetitive trauma by military parachuting on the lumbar spine is not well investigated. Therefore, the purpose of this study was to examine the development of lumbar degenerative changes during a 30-year follow-up in Japanese Ground Self Defense Forces (JGSDF) parachute infantry soldiers with normal lumbar radiographs at entry by comparison with those with non-parachute infantry soldiers. METHODS: 79 non-parachutists and 65 parachutists were included for radiological examination and questionnaires for low back pain (LBP). All subjects were non-commissioned officers with similar socioeconomic status and life styles. The number of parachuting descent during the 30-year in the parachute group ranged from 208 to 630, with an average of 322. RESULTS: The mean age of the subjects was 18.3±0.5 years at entry and 48.5±0.3 years at follow-up. LBP had been experienced by 37% in the non-parachute group and 25% in the parachute group with no significant difference. The nature of their LBP was judged as mild. The prevalence rate of degenerative changes was similar in both groups. Disc space narrowing was detected 37 subjects (47%) in non-parachute group an 23 subjects (35%) in parachute group without significant difference. Vertebral osteophytes were detected in 52 subjects (67%) in non-parachute group and 47 subjects (72%) in parachute group without significant difference. CONCLUSIONS: This study did not identify any significant differences in the development of lumbar degenerative changes between the parachutists and non-parachutists over a 30-year follow-up, suggesting that military parachuting itself does not accelerate the development of intervertebral disc degeneration. Further studies are needed using large cohorts assessed by MRI as well as plain X-ray.

Spin transition in a four-coordinate iron oxide.

Spin transition has attracted the interest of researchers in various fields since the early 1930s, with thousands of examples now recognized, including those in minerals and biomolecules. However, so far the metal centres in which it has been found to occur are almost always octahedral six-coordinate 3d(4) to 3d(7) metals, such as Fe(II). A five-coordinate centre is only rarely seen. Here we report that under pressure SrFe(II)O(2), which features a four-fold square-planar coordination, exhibits a transition from high spin (S = 2) to intermediate spin (S = 1). This is accompanied by a transition from an antiferromagnetic insulating state to a ferromagnetic so-called half-metallic state: only half of the spin-down (d(xz),d(yz)) states are filled. These results highlight the square-planar coordinated iron oxides as a new class of magnetic and electric materials.

Pharmacokinetic study of an oral cephalosporin, cefdinir, in hemodialysis patients.

The pharmacokinetics of cefdinir were investigated in six hemodialysis patients. For the present study, two tests were carried out, one with 4 h of hemodialysis and the other without hemodialysis. Cefdinir was given orally to each patient in a dose of 100 mg, and blood was collected serially for 48 h after dosing in the test without dialysis and for 72 h in the test with dialysis. In the test without dialysis, the maximum plasma concentration (Cmax) was 2.36 +/- 0.53 micrograms/ml (mean +/- standard deviation) and the time to Cmax was 9.00 +/- 2.45 h. The terminal elimination half-life (t1/2) and area under the concentration-time curve (AUC) were 16.95 +/- 1.20 h and 69.05 +/- 14.84 micrograms.h/ml, respectively. In the test with dialysis, t1/2 during hemodialysis decreased approximately to one-sixth of that obtained in the test without dialysis, although t1/2 in the latter elimination phase did not differ from that in the nondialysis test. AUC was reduced to 43% of that in the test without dialysis. The fractional removal of cefdinir by hemodialysis was 61%. These findings indicate that clearance of cefdinir is prolonged in patients with renal failure, and cefdinir is well removed by introduction of hemodialysis, although t1/2 (during hemodialysis) and AUC were two and eight times higher than the data previously reported for healthy volunteers, respectively. The pharmacokinetic data suggest that 100 mg of oral cefdinir once a day would result in a sufficient concentration in plasma in hemodialysis patients, but this remains to be confirmed by multiple-dose studies.

Prevalence of second generation antibody to hepatitis C virus among voluntary blood donors in Osaka, Japan.

To clarify the demographic characteristics of the prevalence of hepatitis C virus (HCV) infection in Osaka, Japan, where hepatocellular carcinoma is common, we investigated the screening data of antibody to HCV (anti-HCV, DAINABOTHCVPHA, second generation assay) in 197,600 voluntary blood donors residing in Osaka. The study found that age-standardized prevalence of anti-HCV was significantly higher than that of HBsAg (2.25 cf 0.86 percent among males, P < 0.001; 2.17 cf 0.55 percent among females, P < 0.001. It was much higher in the blood donors aged 55-64 years than in those aged 16-54 years (8.49 cf 1.32 percent among males, P < 10(-5); 7.26 cf 1.42 percent among females, P < 10(-5)). The prevalence of anti-HCV among males was significantly higher than that of females in the younger (25-34 years) generations (1.02 to 1.49 percent cf 0.71 to 1.13 percent, P < 0.05). A similar tendency was observed in the prevalence of high-titer (> or = 2(12)) anti-HCV. The number of coinfection (both HBsAg and anti-HCV seropositive) was very small, and it was not statistically different from the expected number.

Cumulative risk of hepatocellular carcinoma in hepatitis C virus carriers: statistical estimations from cross-sectional data.

The probability of developing hepatocellular carcinoma (HCC) among hepatitis C virus (HCV) carriers during their life-time is unknown. This paper addresses the estimation of the cumulative risk of HCC among HCV carriers using cross-sectional data. Age-specific prevalences of HCV carriers among the general population were estimated according to 5-year age group, based on the data of 2nd-generation anti-HCV assay in blood donors resident in Osaka (33,226 males and 29,054 females). Seropositivity of anti-HCV among 422 HCC cases, and the Osaka Cancer Registry data on HCC were used in the estimations of 5-year age-specific incidence rates of HCV-linked HCC. Using these data, the cumulative risk, i.e., the probability of contracting HCC within the following 15 years in 50-year-old HCV carriers, was estimated as 28% for males and 6% for females.

Primary liver cancer incidence-rates related to hepatitis-C virus infection: a correlational study in Osaka, Japan.

Osaka, Japan, has one of the highest, primary liver cancer (PLC) incidence-rates in the world, although hepatitis-B virus (HBV) is not endemic. This paper addresses the question of whether the PLC-incidence variation within Osaka Prefecture is due to differences in the prevalence of hepatitis-C virus (HCV) infection. The screening data of antibody to HCV (anti-HCV) and of hepatitis-B virus antigen (HBsAg) in 111,069 male blood-donors, and the incidence data of male PLC obtained from the Osaka Cancer Registry were examined. In a multiple-weighted regression analysis, the age-standardized incidence rate of PLC in the 61 counties within Osaka was correlated significantly with the age-standardized prevalence of anti-HCV with adjustment for that of HBsAg (regression coefficient [RC] = 7.26, P < 0.0001). This finding was consistent with the relationship between the PLC incidence rate and the prevalence of high-titer (> or = 2(12)) anti-HCV (RC = 11.18, P < 0.0001). There was significant association between the prevalence of HBsAg and the PLC incidence rate with adjustment for that of anti-HCV (RC = 7.08, P = 0.018). These findings suggest that the PLC-incidence variation within Osaka is correlated with the geographic pattern of HCV infection as well as that of HBV infection among the residents.

Factors affecting callus distraction in limb lengthening.

Factors affecting the process of callus distraction in limb lengthening include the type of osteotomy, timing and rate of distraction, and stability of fixation. Thirty-two rabbits were studied to evaluate the reliability of transverse osteotomy and delayed distraction and to examine the appropriate rates of distraction. Rabbit tibiae were osteotomized subperiosteally and were subjected to slow distraction using a rigid monolateral external fixator. There was a ten-day waiting period before distraction. The animals were divided into three groups according to the rate of distraction (0.35 mm/12 hours, 0.7 mm/12 hours, 1.4 mm/12 hours). The process of callus formation was monitored by soft x-ray. The reliability of delayed distraction after transverse osteotomy was demonstrated by microangiographic study. Even though intramedullar vessels were interrupted by osteotomy at surgery, blood circulation recovered during the waiting period before distraction. Bone lengthening was successful when distraction was carried out at rates of 0.35 mm/12 hours or 0.7 mm/12 hours. The callus filling a distraction gap showed a characteristic zone structure, i.e., one central radiolucent zone and two adjacent sclerotic zones. Microangiographic study demonstrated the continuity of blood vessels under these rates of distraction. Based on the results of these experiments and clinical experiences on 180 bone lengthenings, the authors believe that a waiting period after osteotomy is more practical than achieving immediate distraction after uncertain corticotomy.