Lath formation mechanisms and twinning as lath martensite substructures in an ultra low-carbon iron alloy.

Lath martensite is the dominant microstructural feature in quenched low-carbon Fe-C alloys. Its formation mechanism is not clear, despite extensive research. The microstructure of an Fe-0.05 C (wt.%) alloy water-quenched at various austenitizing temperatures has been investigated using transmission electron microscopy and a novel lath formation mechanism has been proposed. Body-centered cubic {112}〈111〉-type twin can be retained inside laths in the samples quenched at temperatures from 1050 °C to 1200 °C. The formation mechanism of laths with a twin substructure has been explained based on the twin structure as an initial product of martensitic transformation. A detailed detwinning mechanism in the auto-tempering process has also been discussed, because auto-tempering is inevitable during the quenching of low-carbon Fe-C alloys. The driving force for the detwinning is the instability of ω-Fe(C) particles, which are located only at the twinning boundary region. The twin boundary can move through the ω ↔ bcc transition in which the ω phase region represents the twin boundary.

Diagnostic accuracy of plasma atrial natriuretic peptide concentrations in cats with and without cardiomyopathies.

OBJECTIVES: Plasma atrial natriuretic peptide (ANP) levels have been reported to be elevated in cats with cardiomyopathy. We investigated the diagnostic accuracy of plasma ANP concentration as an indicator of the severity of cardiomyopathies. ANIMALS: This study included 78 control cats and 83 cats with various types of cardiomyopathy. METHODS: This was a prospective multicentre study. Control cats were determined to have a normal heart, and diseased cats were diagnosed by echocardiography. Diseased cats were divided into asymptomatic cats without left atrial dilation (LAD), asymptomatic cats with LAD, and cats with heart failure. Plasma C-terminal ANP concentrations were measured using chemiluminescence. RESULTS: The median plasma ANP concentration in controls was 43.3 (interquartile range, 33.0-56.3) pg/mL. Plasma ANP values were significantly higher in the cardiomyopathic cats with LAD and heart failure, but the values in cats without LAD were comparable to those in control cats. To distinguish cats with cardiomyopathy from controls, a plasma ANP concentration >77.5 pg/mL afforded sensitivity of 66.3% and specificity of 84.6%. Use of plasma ANP concentration >110.9 pg/mL to identify cats with LAD had a sensitivity of 73.6% and specificity of 93.5%. The areas under the receiver-operating characteristic curve were 0.80 and 0.86. CONCLUSIONS: Plasma ANP concentrations were higher in cats with more advanced cardiomyopathy. Although assaying the ANP concentration alone may not help to diagnose cardiac disease, measuring provides additional information that is useful for assessing the severity of cardiomyopathies.

Storage stability of serum formulations containing ofloxacin for autologous serum eardrop therapy.

OBJECTIVE: The storage stability of serum formulations containing ofloxacin for autologous serum eardrop therapy was evaluated for microbiological quality and component stability. METHODS: Sterile serum formulations were prepared by mixing human serum and ofloxacin otic solution (1:1, v/v). To simulate eardrop contamination with external ear surface substances, prepared serum formulations were contaminated with a cotton swab that was rubbed sufficiently on the human external ear. Formulations were stored at 4 °C or room temperature in the dark. Colony forming units (CFUs), ofloxacin, and basic fibroblast growth factor (bFGF) concentrations in the stored serum formulations were determined. RESULTS: The growth of microorganisms derived from the external ear was not detected in serum formulations after storage for 14 days, regardless of temperature. However, microbial growth was detected in serum formulations stored without ofloxacin, indicating that this is necessary for storage. In addition, concentrations of ofloxacin and bFGF did not decrease over 14 days, indicating that ofloxacin and bFGF in serum formulations are stable for this time period. CONCLUSION: The present study indicates that the efficacy and safety of serum formulations used as a therapy for perforated eardrums are stable and safe for at least 14 days.

Parallel comparison of apheresis-collected platelet concentrates stored in four different additive solutions.

BACKGROUND AND OBJECTIVES: Partially replacing plasma with additive solutions in platelet (PLT) concentrates (PCs) may help to reduce transfusion reactions. Constituents of PLT additive solutions (PASs) have been revealed to affect the quality of PCs. Previous studies involved pairwise comparison of identical PLTs with two different PASs or multicomparison using random PLTs with three or more PASs. In this study, we performed parallel comparison using PCs from identical donors with four PASs. In addition to traditional parameters, the release of bioactive substances and plasma proteins was assessed. MATERIALS AND METHODS: Platelets collected four times by apheresis from three donors were suspended in Intersol, SSP+, Composol or M-sol with 35% autologous plasma. The PC parameters, including PLT activation markers, glucose consumption, chemokines and plasma proteins, were assessed during 5-day storage. RESULTS: Mean PLT volumes were decreased in SSP+, Composol and M-sol after 5-day storage, with significant differences, whereas the hypertonic shock response (HSR) was decreased only in Intersol. Glucose consumption was faster in Intersol and M-sol than in SSP+ or Composol. PLT activation, determined as CD62P, sCD62P, sCD40L and RANTES, was significantly higher in Intersol than the other three PASs. No marked change was observed in fibrinopeptide A and C3a in any PASs. CONCLUSIONS: M-sol, SSP+ and Composol effectively preserved the quality of PCs. PLT activation was significantly enhanced in Intersol compared with the other three PASs. These effects seem to depend on magnesium and potassium as a constituent. Parallel comparison further verified that the PC quality largely depended on PASs but not donors.

Charge-density-wave destruction and ferromagnetic order in SmNiC2.

X-ray scattering and electrical resistivity measurements were performed on SmNiC2. Satellite peaks characterized by an incommensurate wave vector (0.5, eta, 0) appear below 148 K, at which the resistivity shows an anomaly. The temperature dependence of thermal diffuse scattering above 148 K suggests critical phonon softening. These results indicate the formation of a charge-density-wave. The satellite peaks abruptly disappear and the resistivity sharply decreases when a ferromagnetic transition takes place at 17.7 K.

Tracheostomy can fatally exacerbate sleep-disordered breathing in multiple system atrophy.

Tracheostomy has been employed to release the airway obstruction at the glottic level and to prevent sudden death in patients with multiple system atrophy (MSA). However, sudden death is possible even after tracheostomy. Nocturnal polysomnography showed that the apnea-hypopnea index became higher after tracheostomy, and all tracheostomized patients had frequent central sleep apneas.

A 13-week subchronic toxicity study of dietary administered morin in F344 rats.

A subchronic toxicity study of a flavonoid morin was performed in both sexes of F344 rats with dietary administration at concentrations of 0%, 0.625%, 1.25%, 2.5% and 5% (w/w) for 13 weeks. No mortality or abnormal clinical signs were observed throughout the experimental period in any group. Although a slight tendency for increase in food intake was noted in both sexes of the 2.5% and 5.0% groups, slight non-significant body weight decrease was observed in 5.0% males. Significant increases in alanine transaminase (ALT; over 2.5%), alkali phosphatase (ALP; 1.25% and 5.0%) and relative liver weights (1.25% and 2.5%) in males and in gamma-glutamyl transpeptidase (gamma-GT), aspartate transaminase (AST), ALT, relative liver weights in the 2.5% and 5.0% females and ALP in 5.0% females were noted. Increased urea nitrogen and relative kidney weights at dose of 1.25% and above and creatinine at 5.0% were observed also in females. On histopathological observation, hepatocyte hypertrophy was detected in 3 of 10 5.0% females. Based on the above findings, the no-observed-adverse-effect level (NOAEL) for both sexes was estimated to be 0.625% (299 and 356 mg/kg b.w./day for males and females, respectively).

Chronic toxicity and carcinogenicity of dietary administered ammonium sulfate in F344 rats.

Chronic toxicity and carcinogenicity studies of ammonium sulfate, used as a food additive in fermentation, were performed in male and female Fisher 344 rats at dietary concentrations of 0%, 0.1%, 0.6% and 3.0% in a 52-week toxicity study and 0%, 1.5% and 3.0% in a 104-week carcinogenicity study. Treatment with ammonium sulfate caused significant increase in kidney and/or liver weights in males and females of the 3.0% diet group, but no effects were found on survival rate, body weights, and hematological, serum biochemical or histopathological parameters at any dose levels in the chronic toxicity study. Regarding carcinogenicity, ammonium sulfate did not exert any significant influence on the incidences of tumors in any of the organs and tissues examined. It was concluded that the no observed adverse effect level of ammonium sulfate was the 0.6% diet, which is equivalent to 256 and 284 mg/kg b.w./day in males and females, respectively, and the compound is non-carcinogenic under the conditions of the study.

Clonal structure and flowering traits of a bamboo [Phyllostachys pubescens (Mazel) Ohwi] stand grown from a simultaneous flowering as revealed by AFLP analysis.

Abstract Although many bamboo species are characterized by simultaneous flowering at long intervals of up to 120 years, few studies have revealed the length of the flowering interval for very-long-lived bamboo species by observing the whole life cycle of a single clone. The flowering interval of Phyllostachys pubescens had been determined to be 67 years by means of observation through the entire life cycle from 1912 to 1979. We observed and analysed the clonal structure and flowering traits of a P. pubescens community which had regenerated from seed in 1930 and began to flower in 1997. Although this interval was again 67 years, flowering and nonflowering culms were mixed, and the flowering event lasted three years in the community. AFLP analysis of DNA samples showed distinct genets that originated from the previous flowering event and that each genet had its own flowering time. This is the first report to show that (i) different genets are mixed in a community of a large bamboo species with a leptomorphic rhizome system, and (ii) a community that originated from a single flowering event can have a range of flowering years.

Sequential analysis of testicular lesions and serum hormone levels in rats treated with a Psoralea corylifolia extract.

In order to clarify pathogenetic targets for the testicular toxicity of a extract of Psoralea corylifolia (P. corylifolia), F344 rats were fed diet containing 3% P. corylifolia extract for up to 12 weeks and subjected to hormone assays and histopathological examination on the testis and epididymis at weeks 1, 2, 4, 8 and 12 (Exp 1). Similar analyses were performed on 1, 3, 7 and 14 days after a single gavage administration of the P. corylifolia extract at a dose of 10 g/kg b.w. (Exp 2). In Exp 1, increase in the numbers of degenerated and exfoliated germ cells and loss of elongated spermatids beyond steps 7 or 8 were initially observed in the seminiferous tubules at week 1, followed by more pronounced degeneration of germ cells with depletion of post-meiotic populations from week 2. The tubular degeneration was associated with Leydig cell atrophy and persistent reduction of serum testosterone and FSH levels throughout the treatment period and a slight reduction of serum LH in later stages. In Exp 2, reduction of serum testosterone and FSH levels preceded degeneration of germ cells in stage VII and VIII tubules at 3 and 7 days after the administration. The results suggest that rapid androgen deprivation reflecting direct interference with Leydig cell function and simultaneous disturbance of the pituitary-testicular axis play pivotal roles in P. corylifolia extract-induced germ cell injury in seminiferous tubules.

Novel surgical repair with bilateral gluteus muscle patching for intractable rectovaginal fistula.

We created a novel surgical repair for intractable rectovaginal fistula and treated four patients who had previously undergone unsuccessful surgery. An X-shaped skin incision was made on the perineum, and then the rectum was carefully divided from the vagina. Defects of both the rectum and the vagina were closed with vertical mattress sutures. The external sphincter muscle also was approximated. The gluteus muscle was identified through another skin incision to the buttock, and cut at the attachment to the femur. Bilateral gluteus muscles were approximated at the midline of the perineum so that the vagina was sufficiently separated from the rectum. Established anorectal angle was 92.5 degrees (SD=6.4 degrees ). Mean resting pressure was 101.3 cm H2O (SD=13.1). All patients retained complete anal function without soiling. The unusual problem of erosion of the posterior vaginal wall with fistulation in a sexually active woman justifies greater efforts, and this surgical technique offers good prospects in this small group of patients.

Abnormal kainic acid receptor density and reduced seizure susceptibility in dystrophin-deficient mdx mice.

Duchenne muscular dystrophy is characterized by a defect in dystrophin, which often causes mental retardation in addition to progressive muscular weakness. As dystrophin is localized in synaptic regions of the CNS, cognitive abnormalities associated with Duchenne muscular dystrophy are attributable to synaptic dysfunction. We report that dystrophin-deficient mdx mice were more resistant to kainic acid-induced seizures but not to GABA antagonist-induced seizures compared with the control mice. The kainic-acid receptor density in the brain was significantly lower in the mdx than in the control, although the density of muscarinic cholinergic receptors, another important neurotransmitter receptor for cognitive function, was normal. Moreover, mdx had significantly lower Timm staining intensity in the mossy fibers, which originate from the dentate granule cells and terminate on the pyramidal cells in the CA3 of the hippocampus. These results suggest that an instability of neurotransmitter receptors, such as kainate-type glutamate receptors, on synaptic membranes due to the disruption of dystrophin complex induces inefficient neurotransmission in Duchenne muscular dystrophy patients.

Resonant two-magnon Raman scattering and photoexcited States in two-dimensional mott insulators.

We investigate the resonant two-magnon Raman scattering in two-dimensional (2D) Mott insulators by using a half-filled 2D Hubbard model in the strong coupling limit. By performing numerical diagonalization calculations for small clusters, we find that the Raman intensity is enhanced when the incoming photon energy is not near the optical absorption edge but well above it, being consistent with experimental data. The absence of resonance near the gap edge is associated with the presence of background spins, while photoexcited states for resonance are found to be characterized by the charge degree of freedom. The resonance mechanism is different from those proposed previously.

Significant accumulation of C(4)-specific pyruvate, orthophosphate dikinase in a C(3) plant, rice.

The C(4)-Pdk gene encoding the C(4) enzyme pyruvate, orthophosphate dikinase (PPDK) of maize (Zea mays cv Golden Cross Bantam) was introduced into the C(3) plant, rice (Oryza sativa cv Kitaake). When the intact maize C(4)-Pdk gene, containing its own promoter and terminator sequences and exon/intron structure, was introduced, the PPDK activity in the leaves of some transgenic lines was greatly increased, in one line reaching 40-fold over that of wild-type plants. In a homozygous line, the PPDK protein accounted for 35% of total leaf-soluble protein or 16% of total leaf nitrogen. In contrast, introduction of a chimeric gene containing the full-length cDNA of the maize PPDK fused to the maize C(4)-Pdk promoter or the rice Cab promoter only increased PPDK activity and protein level slightly. These observations suggest that the intron(s) or the terminator sequence of the maize gene, or a combination of both, is necessary for high-level expression. In maize and transgenic rice plants carrying the intact maize gene, the level of transcript in the leaves per copy of the maize C(4)-Pdk gene was comparable, and the maize gene was expressed in a similar organ-specific manner. These results suggest that the maize C(4)-Pdk gene behaves in a quantitatively and qualitatively similar way in maize and transgenic rice plants. The activity of the maize PPDK protein expressed in rice leaves was light/dark regulated as it is in maize. This is the first reported evidence for the presence of an endogenous PPDK regulatory protein in a C(3) plant.

sFlt-1 gene-transfected fibroblasts: a wound-specific gene therapy inhibits local cancer recurrence.

Local recurrence occurs frequently at the site of injury after surgical resection. On the other hand, fibroblasts have been shown to accumulate in the injured area to heal and remodel the damaged tissues. Therefore, fibroblasts are likely to be useful as wound-specific vectors for delivery of genes to sites of surgically injury. The present study was performed to investigate wound-specific migration of exogenously administered fibroblasts and efficacy of gene therapy using genetically engineered fibroblasts in an i.p. wound recurrence model in rats. We demonstrated that fibroblasts transfected with the GFP gene accumulated specifically around the site of injury immediately after i.p. injection. Then, fibroblasts transfected with an adenovirus designated as AdFex that encoded the soluble form of Flt-1 (sFlt-1), a vascular endothelial growth factor receptor, were administered i.p. to the rats to examine inhibition of tumor growth. At day 16 after implantation, a significantly smaller tumor volume and less microvessel density in wound sites were observed in the AdFex/fibroblast-treated rats than in controls. Furthermore, this treatment also resulted in an improved survival rate. In conclusion, autologous fibroblasts show promise as a wound-specific vector for gene therapy, and administration of sFlt-1 gene-engineered fibroblasts contributed to local control of the tumor around the injured tissue.

[Follow-up study of myasthenia gravis: evaluation of thymectomy in 300 patients].

From June 1975 to March 1999, 300 patients of myasthenia gravis(MG) have undergone thymectomy. Among these patients, 69 cases were classified as ocular type of MG(including 15 cases with thymoma), and 231 were generalized type of MG(including 86 cases with thymoma). The efficacy of the treatment was investigated by evaluating current patients' life activity, which is classified in 6 groups(Remission, Much Improved, Improved, Unchanged, Worse, and Died). Among the 214 cases without thymoma, Remission was 75, Much Improved was 56, and Improved was 55, namely 86.9% of these cases showed Improved or better. Among 86 cases with thymoma, Remission was 14, Much Improved was 21, and Improved was 32, namely 77.9% of these cases showed Improved or better. We concluded that post-operative outcome of these patients regardless of thymoma were generally satisfactory, but it was necessary to carry out long term careful follow-up.

Lack of modifying effects of eugenol on development of lung proliferative lesions induced by urethane in transgenic mice carrying the human prototype c-Ha-ras gene.

To investigate the modifying effects of eugenol (EUG), a component of cigarette smoke, on lung carcinogenesis, male and female transgenic mice carrying the human prototype c-Ha-ras gene (rasH2 mice) were given a single intraperitoneal injection of 250 mg/kg urethane (UR) or saline, followed by a diet containing 6,000 ppm EUG or basal diet for 26 weeks. Their non-transgenic CB6F1 littermates (non-Tg mice) were also treated in the same manner. In both male and female rasH2 mice, alveolar/bronchiolar hyperplasias, adenomas and carcinomas were observed in all UR-treated groups. However, there were no significant intergroup differences in the incidences and multiplicities of these lesions between the UR alone and UR + EUG groups. In non-Tg mice, alveolar/bronchiolar hyperplasias, adenomas or carcinomas were sporadically observed in UR-treated groups of both sexes, with no significant differences in the incidences and multiplicities between the UR alone and UR + EUG groups. There were no intergroup differences between them in the PCNA-positive ratios of adenomas or carcinomas and the areas of adenomas or carcinomas to the whole lung area examined. The present results suggest that the EUG treatment does not exert modifying effects on lung carcinogenesis induced by UR in both male and female rasH2 mice and non-Tg mice.

A prostaglandin E2 receptor subtype EP1 receptor antagonist (ONO-8711) reduces hyperalgesia, allodynia, and c-fos gene expression in rats with chronic nerve constriction.

UNLABELLED: Chronic constriction injury (CCI) of the sciatic nerve in rats induces persistent mechanical hyperalgesia and allodynia. CCI is widely known as a model of neuropathic pain, and many studies using this model have been reported. Recently, c-fos has been used as a neural marker of pain, and various studies have assessed the relationship between hyperalgesia and c-fos expression in the lumbar spinal cord. In this study, we examined the role of a prostaglandin E2 receptor subtype EP1 receptor antagonist (ONO-8711) in a rat CCI model. EP1 receptor antagonist (EP1-ra) oral administration from day 8 to day 14 significantly reduced hyperalgesia and allodynia in the three pain tests on day 15. EP1-ra treatment from day 8 to 14 also reduced c-fos-positive cells in laminae I-II, III-IV, and V-X compared with saline treatment. A single dose of EP1-ra treatment on day 8 significantly reduced hyperalgesia and allodynia at 1 h and 2 h after administration, but the efficacy was not observed at 24 h. We conclude that EP1-ra treatment may be useful for hyperalgesia and allodynia and that EP1 receptor mechanisms are involved in the maintenance of c-fos gene expression induced by nerve injury. IMPLICATIONS: We examined whether a prostaglandin E2 receptor subtype EP1 receptor antagonist abrogates neuropathic pain induced by chronic constriction injury model in rats. The EP1 receptor antagonist significantly reduced hyperalgesia, allodynia, and c-fos positive cells. These findings suggested that EP1 receptor antagonists may have a role in treatment of neuropathic pain.