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SUMMARY: This paper proposes a new drive circuit for reducing the switching current ripples in a switched reluctance motor (SRM). The authors have already presented an instantaneous flat torque control for SRMs, and confirmed its effectiveness through experimental results. However, the switching current ripples also cause torque ripples, and therefore, the current ripples should be decreased to reduce the torque ripples even more. The proposed circuit with parallel capacitor can realize such a reduction. The validity of the proposed drive circuit is verified experimentally. [ABSTRACT FROM AUTHOR]

Azoospermia affects up to 1% of adult men. Non-obstructive azoospermia is a multifactorial disorder whose molecular basis remains largely unknown. To date, mutations in several genes and multiple submicroscopic copy-number variations ( CNVs) have been identified in patients with non-obstructive azoospermia. The aim of this study was to clarify the contribution of nucleotide substitutions in known causative genes and submicroscopic CNVs in the genome to the development of non-obstructive azoospermia. To this end, we conducted sequence analysis of 25 known disease-associated genes using next-generation sequencing and genome-wide copy-number analysis using array-based comparative genomic hybridization. We studied 40 Japanese patients with idiopathic non-obstructive azoospermia. Functional significance of molecular alterations was assessed by in silico analyses. As a result, we identified four putative pathogenic mutations, four rare polymorphisms possibly associated with disease risk, and four probable neutral variants in 10 patients. These sequence alterations included a heterozygous splice site mutation in SOHLH1 and a hemizygous missense substitution in TEX11, which have been reported as causes of non-obstructive azoospermia. Copy-number analysis detected five X chromosomal or autosomal CNVs of unknown clinical significance, in addition to one known pathogenic Y chromosomal microduplication. Five patients carried multiple molecular alterations. The results indicate that monogenic and oligogenic mutations, including those in SOHLH1 and TEX11, account for more than 10% of cases of idiopathic non-obstructive azoospermia. Furthermore, this study suggests possible contributions of substitutions in various genes as well as submicroscopic CNVs on the X chromosome and autosomes to non-obstructive azoospermia, which require further validation. [ABSTRACT FROM AUTHOR]

Background This study aimed to examine the effects of Lactobacillus casei strain Shirota (LcS) on gut-brain interactions under stressful conditions. Methods Three double-blind, placebo-controlled trials were conducted to examine the effects of LcS on psychological and physiological stress responses in healthy medical students under academic examination stress. Subjects received LcS-fermented milk or placebo daily for 8 weeks prior to taking a national standardized examination. Subjective anxiety scores, salivary cortisol levels, and the presence of physical symptoms during the intervention were pooled and analyzed. In the animal study, rats were given feed with or without LcS for 2 weeks, then submitted to water avoidance stress (WAS). Plasma corticosterone concentration and the expression of cFos and corticotropin releasing factor (CRF) in the paraventricular nucleus (PVN) were measured immediately after WAS. In an electrophysiological study, gastric vagal afferent nerve activity was monitored after intragastric administration of LcS to urethane-anesthetized rats. Key Results Academic stress-induced increases in salivary cortisol levels and the incidence rate of physical symptoms were significantly suppressed in the LcS group compared with the placebo group. In rats pretreated with LcS, WAS-induced increases in plasma corticosterone were significantly suppressed, and the number of CRF-expressing cells in the PVN was reduced. Intragastric administration of LcS stimulated gastric vagal afferent activity in a dose-dependent manner. Conclusions & Inferences These findings suggest that LcS may prevent hypersecretion of cortisol and physical symptoms under stressful conditions, possibly through vagal afferent signaling to the brain and reduced stress reactivity in the PVN. [ABSTRACT FROM AUTHOR]

An abstract of the article "Prognostic factors in preterm small-for-gestational age infants for the outcome at 18 months of age: a Japanese multicentre study" by J. Sasahara et al. is presented.

An abstract of the article "'Wait and see' strategy is acceptable for premature constriction of ductus arteriosus" by K. Kim and colleagues is presented.

A prospective clinical study was performed in the reproduction centre of Ichikawa General Hospital ( Chiba, Japan) to investigate the relationship between sperm quality and serum oestradiol ( E2) level in male partners of infertile couples. The semen parameters and blood samples were assessed in relation to several variables, including body mass index ( BMI) and serum oestradiol ( E2) levels. Four hundred and nine male partners of infertile couples aged 22-55 years (mean: 36.5 years) were referred to the reproduction centre. In total, 143 patients (35.0%) were included in the low E2 level group (18 pg ml−1 ≥ E2). Serum E2 levels were slightly correlated with testosterone levels, BMI and serum FSH levels. Total motile sperm count and morphology were decreased in low E2 level group. In multivariate analysis, serum testosterone, E2 levels, existence of varicocele and age were risk factors for decreased semen quality. Serum E2 might be associated with BMI, serum testosterone level and spermatogenesis. [ABSTRACT FROM AUTHOR]

Objective To investigate the mechanisms that cause damage to root formation as a result of irradiation to the mouse head, morphological changes in molar dental roots and cell dynamics in Hertwig's epithelial root sheath ( HERS), and surrounding mesenchymal tissue were examined. Materials and Methods To perform the experiments, 5-day-old C57 BL/6 mice were randomly divided into three groups: the control group (0 Gy) and irradiated groups (10 and 20 Gy). Micro- CT analysis, HE staining, immunohistochemistry analysis, and TUNEL assay were then performed. Results Roots in irradiated mice were dose-dependently shorter than those of control mice. Cells located outside the root dentin, with abnormal morphology in irradiated mice, were positive for an odontoblast marker. HERS fragmentation occurred earlier in irradiated mice than in control mice, and HERS was trapped by the calcified apical tissue. A dose-dependent reduction in the number of proliferating cells within the apical dental pulp and periapical periodontal ligament surrounding HERS was observed in irradiated mice. Apoptotic cells in the dental pulp and periodontal ligament surrounding HERS were hardly seen. Conclusions These results indicate that the early disappearance of HERS and the proliferative suppression of the surrounding mesenchymal cells, which was induced by irradiation, caused dental root malformation. [ABSTRACT FROM AUTHOR]

Aims To assess the effects of renal impairment (RI) on the efficacy and safety of ipragliflozin in patients with type 2 diabetes mellitus (T2DM). Methods A cohort of Japanese patients with T2DM and mild to moderate RI and poor glycaemic control, despite diet/exercise therapy alone or diet/exercise therapy in combination with an oral hypoglycaemic agent (an α-glucosidase inhibitor, a sulfonylurea, or pioglitazone), were randomized in a double-blind manner to 50 mg ipragliflozin or placebo once daily for 24 weeks. The patients continued open-label ipragliflozin for a 28-week extension period (total treatment duration: 52 weeks). Results Ipragliflozin significantly decreased glycated haemoglobin (HbA1c) and fasting plasma glucose ( FPG) levels and body weight from baseline to week 24 (last observation carried forward) compared with placebo in all patients with RI. The decreases in HbA1c and FPG levels were statistically significant in patients with mild RI, but not in patients with moderate RI. Ipragliflozin significantly reduced body weight in both RI groups. The improvements in glycaemic control were maintained in the 28-week extension period. Ipragliflozin was associated with no clinically significant safety concerns, and its safety profiles were not influenced by the severity of RI. Conclusions Ipragliflozin significantly improved glycaemic control and body weight in patients with T2DM with mild RI, but did not improve glycaemic control in patients with moderate RI. Ipragliflozin is a valid treatment option for patients with mild RI but not those with moderate RI. [ABSTRACT FROM AUTHOR]

A prospective study was performed in the Reproduction Center of Ichikawa General Hospital (Chiba, Japan) to assess the relationship between dyslipidaemia and sperm quality and serum hormone levels in male patients in Japan. The semen parameters and blood samples were assessed in relation to several variables, including body mass index (BMI) and serum triglyceride (TG) levels. Between 2011 and 2012, 167 male partners of infertile couples aged 22-46 years (mean: 36.5 years) were referred to the reproduction centre. In total, 66 patients (39.5%) had hypertriglyceridaemia (TG level ≥ 150 mg dl−1). There was no significant relationship between serum TG levels and sperm concentration or motility; however, the serum TG level was positively associated with the sperm morphological traits. Furthermore, the serum levels of glutamic oxaloacetic transaminase and glutamic pyruvic transaminase were associated with the serum TG levels. By contrast, a negative relationship between serum testosterone and TG levels was discovered. [ABSTRACT FROM AUTHOR]

Objectives To document outcome and to explore prognostic factors in fetal left congenital diaphragmatic hernia (CDH). Methods This was a multicenter retrospective study of 109 patients with prenatally diagnosed isolated left CDH born between 2002 and 2007. The primary outcome was intact discharge, defined as discharge from hospital without major morbidities, such as a need for respiratory support including oxygen supplementation, tube feeding, parenteral nutrition or vasodilators. All patients were managed at perinatal centers with immediate resuscitation, gentle ventilation (mostly with high-frequency oscillatory ventilation) and surgery after stabilization. Prenatal data collected included liver and stomach position, lung-to-head ratio, gestational age at diagnosis and presence or absence of polyhydramnios. Stomach position was classified into four grades: Grade 0, abdominal; Grade 1, left thoracic; Grade 2, less than half of the stomach herniated into the right chest; and Grade 3, more than half of the stomach herniated into the right chest. Results Overall intact discharge and 90-day survival rates were 65.1% and 79.8%, respectively. Stomach herniation was classified as Grade 0 in 19.3% of cases, Grade 1 in 45.9%, Grade 2 in 13.8% and Grade 3 in 21.1%. Multivariate analysis revealed that liver position was the strongest prognostic variable for intact discharge, followed by stomach position. Based on our results, we divided patients into three groups according to liver (up vs. down) and stomach (Grade 0-2 vs. Grade 3) position. Intact discharge rates declined significantly from liverdown (Group I), to liver-up with stomach Grade 0-2 (Group II), to liver-up with stomach Grade 3 (Group III) (87.0%, 47.4% and 9.5% of cases, respectively). Conclusion Current status and outcomes of prenatally diagnosed left CDH in Japan were surveyed. Stomach herniation into the right chest was not uncommon and its grade correlated with outcome. The combination of liver and stomach positions was useful to stratify patients into three groups (Group I-III) with different prognoses. [ABSTRACT FROM AUTHOR]

Background and Objective: The elastic fiber system comprises oxytalan, elaunin and elastic fibers, differing in their relative microfibril and elastin contents. Human periodontal ligaments contain oxytalan fibers (pure microfibrils). Periodontal ligaments are continuously exposed to various functional forces, such as tooth movement and occlusal loading. We have reported that bundles of microfibrils coalesce in response to mechanical strain in cultured periodontal ligament fibroblasts, as assessed in terms of their positivity for fibrillin-1 (the major component of microfibrils). However, the mechanism of microfibril coalescence is unclear. We hypothesized that the fibrillin-1-binding molecule, fibulin-5, contributes to oxytalan fiber formation under mechanical strain. Material and Methods: We subjected periodontal ligament fibroblasts to stretching in order to examine the effects of fibulin-5 on the formation of oxytalan fibers in cell/matrix layers. We transfected periodontal ligament cells with small interference RNA for fibulin-5, then examined oxytalan fibers using immunofluorescence and electron microscopy. Results: Immunofluorescence showed that fibrillin-1-positive microfibrils coalesced as a result of stretching, compared with cells that were not subjected to stretching. Fibulin-5 colocalized on fibrillin-1-positive microfibrils. Stretching increased fibulin-5 gene expression and protein deposition. Immunofluorescence and immunogold electron microscopy analysis revealed that fibulin-5 suppression inhibited the coalescence of microfibrils under stretching conditions. Conclusion: These results suggest that fibulin-5 up-regulated in response to tension strain may control the formation of microfibril bundles in periodontal ligament. [ABSTRACT FROM AUTHOR]

Background and Objective: Oxytalan fibers, as well as collagen fibers, are the structural components of periodontal ligaments. Periodontal ligaments are continuously exposed to various functional forces. However, the behavior of oxytalan fibers under mechanical strain has not been investigated. We hypothesized that strain would alter the amount and appearance of oxytalan fibers in terms of positivity for their major components, fibrillin-1 and fibrillin-2. Material and Methods: We subjected periodontal ligament fibroblasts to stretching strain to examine the effects on their formation of oxytalan fibers in cell/matrix layers. Results: Stretching increased the levels of fibrillin-1 and fibrillin-2 by 25% relative to the control, but did not affect the gene expression level of either type of fibrillin. Immunofluorescence and immunogold electron microscopy analysis revealed that bundles of oxytalan fibers became thicker under stretching conditions. Conclusion: These results suggest that tension strain functionally regulates microfibril assembly in periodontal ligament fibroblasts and thus may contribute to the homeostasis of oxytalan fibers in periodontal ligaments. [ABSTRACT FROM AUTHOR]

Prevalence, magnetic resonance imaging (MRI) findings, cognitive function and depression are four major aspects of vascular cognitive impairment no dementia (vascular CIND). We performed a community-based study to examine these using 497 community-residents aged 65 years or older. Vascular CIND was defined as a clinical dementia rating (CDR) 0.5 with cerebrovascular disease. Several neuropsychological tests were performed, including MMSE, Geriatric Depression Scale (GDS), and Trail Making Test (TMT). Cerebrovascular disease and white matter lesions were visually assessed using MRI. Prevalence of vascular CIND, localization of cerebrovascular disease, and the relationships amongst MRI findings, white matter lesions, cognitive impairment and depression were analyzed. The prevalence of vascular CIND was 8.5% amongst the total population, corresponding to the rate being 37.2% amongst the CDR 0.5 participants. Compared with the CDR 0, the CDR 0.5 group had more subjects with strategic cerebrovascular disease in the thalamus, etc. No effects of cerebrovascular disease on MMSE and GDS scores were found, but the CDR 0.5/strategic cerebrovascular disease group showed impaired TMT-B scores. In the CDR 0 group, only anterior periventricular hyperintensity was associated with TMT-A score independent of cerebrovascular disease. A vascular CIND population was identified, and executive dysfunction in this population is probably based on an impaired fronto-subcortical circuit. [ABSTRACT FROM AUTHOR]

Background Coronary artery disease can be diagnosed from stress and delayed images of myocardial single photon emission computed tomography (SPECT) using technetium-99 m-tetrofosmin (TcTF). However, the negative predictive value of stress SPECT images after a single injection of a low tracer dose remains unknown. Thus, the present study investigates whether normal stress SPECT results predict event-free survival. Materials and methods We screened 302 consecutive patients who were randomly assigned to two groups for myocardial ischaemia using either stress SPECT with a low dose of TcTF (296 MBq, TcTF group, n = 150) or stress together with rest SPECT using thallium201 chloride (TlCl, 111 MBq; TlCl group, n = 152) as the tracer. A total of 80 patients with abnormal SPECT findings were excluded and the remaining 222 with normal results (age, 66·5 ± 0·7 years; TcTF/TlCl, 112/110) were enrolled in the present study and followed up for 401 ± 9 days, with the endpoint being ischaemic cardiac events. Results The incidence of cardiac events did not differ between the two groups (0·9% and 0·0% in TcTF and TlCl groups, respectively). The cost and duration of TcTF and TlCl SPECT examinations were about 425 and 603 Euros and 50 and 280 min, respectively. Conclusions The negative predictive values of stress SPECT using a low dose of TcTF and of combined stress and rest SPECT using TlCl did not differ and both were clinically acceptable. Thus, stress SPECT using low dose TcTF is useful in screening patients for myocardial ischaemia. [ABSTRACT FROM AUTHOR]

Background Twelve years has passed since we introduced laparoscopic surgery for gastroduodenal perforation. Aim To list problems and to investigate the feasibility of our clinical protocol for treatment of gastroduodenal ulcer perforation. Methods Case records of 62 patients and histology samples of 9 patients undergoing surgery for gastroduodenal perforation were retrospectively reviewed. Results Laparoscopic omental implantation is feasible for some cases of perforated peptic ulcer in patients who have either stenosis or massive perforations. In patients undergoing laparoscopic omental implantation, oral ingestion of water was started at 3.3 ± 0.5 post-operative days. Helicobacter pylori was positive in 27 of 35 patients (77%). Of 22 cases in whom intraoperative ascitic culture was taken, Candida was positive in nine (41%), and in six of eight cases involving wound infection or intraperitoneal abscess. Histological examination of resected stomach revealed the fungi with hypha formation at the base of the ulcer in 44% of patients. Conclusions Laparoscopic omental implantation was more feasible than in the past. The possibility of Candida infection and subsequent abscess formation must be considered in patients with gastroduodenal ulcer perforation. [ABSTRACT FROM AUTHOR]

Background Endoscopic classifications were reported to reflect the pathophysiology of gastric mucosa. However, relationship between gastric lesions and classifications has not been examined well. Aim To investigate the relationship between endoscopic classifications and cancers or ulcers. Methods In this study, 487 patients undergoing upper gastrointestinal endoscopy in Takahashi Clinic and 257 patients with early gastric cancer in Keio University Hospital were enrolled. Results Incidence of reflux oesophagitis was higher in Helicobacter pylori-negative patients. K-form was better in the H. pylori-positive patients. Most cancers in the patients with the closed-type or reflux oesophagitis were of undifferentiated types. Incidences of ulcers were highest in C-2 and C-3 in which the borders of atrophy cross the medial oblique muscle bundle, the border circular muscle bundle or both, and 94% of ulcers in C-2 and C-3 stomach were located along the lesser curvature. Conclusion The predominant existence of undifferentiated types in patients with reflux oesophagitis or closed-type stomach can be useful information for early diagnosis of cancers. The relationship between the Kimura–Takemoto classification and ulcer location may explain why H. pylori infection is related to ulcer formation along the lesser curvature. [ABSTRACT FROM AUTHOR]

Objectives. KL-6 is a specific marker in patients with interstitial lung diseases (ILDs); however, the relationship between elevated levels of KL-6 and subsequent mortality is not well defined. To determine if elevated serum levels of KL-6 are associated with increased mortality, and to identify the most suitable cut-off level of KL-6 by which to distinguish between good prognosis and poor prognosis, we evaluated the prognostic significance of serum KL-6 levels in patients with stable-state ILDs. Methods. Two hundred and nineteen patients diagnosed with ILDs (152 with idiopathic interstitial pneumonia and 67 with collagen disease-associated pulmonary fibrosis) at Tsukuba University Hospital from April 1999 to October 2005 were entered in this study. Serum KL-6 levels in patients with ILDs were measured with a commercially available enzyme immunoassay kit, and these patients were then followed up. Results. During the follow-up period, 58 of the 219 patients died of respiratory failure. Patients who died during this period had higher levels of KL-6 than did those who did not ( P = 0.0004). The receiver operating characteristic curve analysis showed 1000 U mL−1 as the most suitable cut-off level by which to distinguish between the two groups of patients. The 95% specificity serum KL-6 level with poor outcome was 2750 U mL−1. In univariate and multivariate analysis, elevated serum KL-6 (>1000 U mL−1) in the stable state indicated poor prognosis ( P = 0.0005, log-rank test; P = 0.0001, Cox proportional hazard model). Conclusions. Elevated KL-6 level may provide simple, yet valuable information by which to identify patients with ILDs who are at increased risk for subsequent mortality. [ABSTRACT FROM AUTHOR]

OBJECTIVE: To investigate the effects of vibration (Vib) and hyaluronic acid (HA) on 3-dimensional cultured cartilage. METHODS: Chondrocytes were obtained from metatarsophalangeal joints of freshly killed 6-month-old pigs. Twenty-four-well plates containing type I collagen sponge disks were used to culture samples. The frequency and the amplitude of the vibration of the well plate were 100 Hz and 0.5 nm, respectively. We produced 3-dimensional cartilage tissue using HA and vibration with collagen sponge as a carrier. Four different culture conditions were examined: a control HA-Vib- group, an HA-Vib+ group, an HA+Vib- group, and an HA+Vib+ group. Each group was cultured for 2 weeks. After culture days 3, 7, 10, and 14 (every 3.5 days), the levels of chondroitin 4-sulfate (C4S) and chondroitin 6-sulfate (C6S) isomers synthesized in each culture medium were measured. Histologic analysis, immunohistochemical analysis, and electron microscopic examination were performed. RESULTS: Mean C4S and C6S synthesis had increased rapidly after 7 days of culture and continued to increase thereafter. There were significant differences among the 4 groups (P < 0.01). Synthesis of both C4S and C6S was most abundant in the HA+Vib+ group and the lowest in the HA-Vib- group. After 1 and 2 weeks of culture, the chondrocytes had formed stratified structures on the collagen sponges in all groups, although the thickest structure was observed in the HA+Vib+ group and the thinnest in the HA-Vib- group. Under immunofluorescence, the HA+Vib+ group exhibited the strongest chromatic features. Under electron microscopy, the chondrocytes in the HA+Vib+ group exhibited many long and slender prominences on their surface, and extracellular substance could be observed associated with the cells. CONCLUSION: Our results indicate that the combination of vibration and HA activates the production of proteoglycan in 3-dimensional cultured chondrocytes and stimulates MAPK and beta-catenin. This suggests that some mechanoreceptors for vibration exist on the plasma membrane of chondrocytes and activate the intracellular signal transduction system. [ABSTRACT FROM AUTHOR]

MyD88 is a key adaptor molecule for signalling via Toll-like receptors (TLRs) and the response to gut commensal microbes. To investigate the role of TLRs/MyD88 pathway in the development of the gut-associated lymphoid tissue (GALT), we examined the development of Peyer's patches (PPs) and cryptopatch (CP), and also one of effector compartment, intraepithelial lymphocyte (IEL) in MyD88–/–, TLR2–/– and TLR4–/– mice. In MyD88–/– mice, the organogenesis of PPs was not disturbed. However, PPs in 2-week-old MyD88–/– mice were significantly smaller than those in MyD88+/– mice. Also, in 2-week-old TLR4–/–, but not TLR2–/– mice, PPs did not develop rapidly. The development of PPs in MyD88–/– and TLR4–/– mice was completely recovered in 10 weeks. PP cells from MyD88–/– mice showed significant decrease in proliferation when stimulated with lipopolysaccharide. The development of CP and IEL was also normal in 10-week-old MyD88–/– mice. These results suggest that the TLRs/MyD88 pathway might be involved in the development of PPs only at early postnatal stage, and TLRs/MyD88-independent signalling is critically involved in the development of GALT in adult mice. [ABSTRACT FROM AUTHOR]

Abstract Lympho-haemopoietic progenitors residing in murine gut cryptopatches (CPs) have been shown to generate intestinal extrathymic intraepithelial lymphocytes (IELs). However, the role of CPs in the development of intestinal inflammation remains unclear. To investigate the role of CPs in the development of intestinal inflammation, we examined SAMP1/Yit mice, which spontaneously develop a chronic intestinal inflammation localized to the terminal ileum and cecum. Here, we showed the sharp correlation between the disease onset and the decreased number of CPs, resulting in decreased number of both thymus-independent IELs including T-cell receptor γδ[sup +] (TCRγδ[sup +] ) and CD8αα[sup +] TCRαβ[sup +] cells but not thymus-dependent CD8αβ[sup +] TCRαβ[sup +] and CD4[sup +] TCRαβ[sup +] cells in SAMP1/Yit mice. These data provide the first suggestion that thymus-independent IELs derived from CP might play protective role against the onset and the development of intestinal inflammation. [ABSTRACT FROM AUTHOR]

BSTRACT: Continuous method with microbubbles of supercritical carbon dioxide (SC-CO2) was applied to enzyme inactivation in a buffer system, which has a buffer capacity similar to commercial liquid foods (natural juices, fruit drinks, Japanese sake). By continuous treatment with microbubbles of SC-CO2, α-amylase and acid protease were effectively inactivated rather than by heat treatments. Compared with the inactivation efficiencies of these enzymes in deionized water by continuous treatment with microbubbles of SC-CO2, that of α-amylase was slightly lower, but that of acid protease was not in the buffer system. These results suggest that this method enables the effective inactivation of enzymes, although inactivation efficiency by this method was affected by initial pH and the buffer action of samples. [ABSTRACT FROM AUTHOR]

Abstract Although the effects of gravity on root growth are well known and interactions between light and gravity have been reported, details of root phototropic responses are less documented. We used high-resolution image analysis to study phototropism in primary roots of Zea mays L. Similar to the location of perception in gravitropism, the perception of light was localized in the root cap. Phototropic curvature away from the light, on the other hand, developed in the central elongation zone, more basal than the site of initiation of gravitropic curvature. The phototropic curvature saturated at approximately 10 µ mol m-2 s-1 blue light with a peak curvature of 29 ± 4°, in part due to induction of positive gravitropism following displacement of the root tip from vertical during negative phototropism. However, at higher fluence rates, development of phototropic curvature is arrested even if gravitropism is avoided by maintaining the root cap vertically using a rotating feedback system. Thus continuous illumination can cause adaptation in the signalling pathway of the phototropic response in roots. [ABSTRACT FROM AUTHOR]

Summary All phloem-feeding Homoptera possess symbiotic microorganisms. Although the phylogenetic position and anatomical location of the micro- organisms differ, the underlying theme of the symbiosis is the same; the microorganisms improve the nutritional quality of the diet through the provision of essential amino acids. The symbiosis has been well documented in aphids, but little information is available from other homopteran groups. The impact of the loss of bacterial symbionts in the pea aphid Acyrthosiphon pisum Harris and eukaryotic yeast-like symbionts in the Asian rice brown planthopper Nilaparvata lugens Stål was examined in parallel. The weight and relative growth rate of aphids and planthoppers was significantly reduced by symbiont loss, and characteristic features of aposymbiotic pea aphids, so-called ‘metabolic signatures’, were, for the first time, observed in aposymbiotic N. lugens. For example, the amount of protein per unit fresh weight was reduced by 26 and 10%, and the free amino acid levels increased 1.8- and 1.4-fold, in aposymbiotic A. pisum and N. lugens, respectively. In addition, the concentration of the amino acid glutamine was elevated in the tissues of aposymbiotic insects. The data are discussed in the context of our current understanding of the nutritional role of the symbiosis and the mechanisms of nitrogen metabolism in the two insect species. It is concluded that the metabolic adjustments of the insects to symbiont loss are broadly equivalent. [ABSTRACT FROM AUTHOR]

Desmoglein 3 is a cadherin-like calcium-dependent cell adhesion molecule expressed primarily in suprabasal keratinocytes of the epidermis. In this study, we have cloned the full-length cDNA and characterized the entire gene structure for the mouse desmoglein 3 gene (Dsg3). Isolation of overlapping cDNA clones, together with 5′ and 3′ rapid amplification of cDNA ends (RACE), allowed delineation of the entire coding sequence. The transcriptional initiation site was confirmed by primer extension and reverse transcription polymerase chain reaction analysis. The entire cDNA consisted of 6407 bp with an open reading frame of 2979 bp, and the deduced polypeptide contained 993 amino acids. Comparison of mouse and human desmoglein 3 amino acid sequences demonstrated 85.6% homology. Computer analysis suggested the presence of a transmembrane segment, 5 potential calcium binding sites, and a RAL motif which corresponds to the HAV motif, the potential site for homophilic interaction of typical cadherins. The mouse desmoglein 3 gene consisted of 15 exons in chromosome 18. Comparison of the intron–exon organization of Dsg3 with various cadherins from different species revealed remarkable conservation. This relatively high level of conservation both at the protein and genomic level suggests that desmoglein 3 plays an important role in keratinocyte cell–cell adhesion.Note. [ABSTRACT FROM AUTHOR]

Vascularization of the periodontal ligament was examined to developing upper first molars of rats from 5 to 30 d after birth with light and scanning electron microscopy. Formation of the vascular network in the periodontal ligament (PDL) started with the beginning of root formation. The PDL vessels derived from the basal region of the tooth germ ran parallel to the long axis of the root and connected with the vascular network of the enamed organ at the cervical end. The boundary of these 2 networks was initially indistinct but became clearer with the progress of root formation. The PDL vessel further elongated longitudinally and connected with each other by lateral branches to form a coarse mesh. Other vessels derived from te alveolar bone via Volkman's canals also contributed to the vascular construction of the PDL. The vessels from the alveolar bone provided branches to the existing mesh of the PDL. Consequently, the vascular network of the PDL consisted of vessels from 2 sources:1 derived from the basal region of the tooth germ, and the other from the alveolar bone. The density of the vascular network reduced with the progress of root formation, especially at the middle part of the root, but the mesh at the apical region maintained a basket-like structure. [ABSTRACT FROM AUTHOR]

Summary An interleukin‐12 (IL‐12) expression plasmid was transferred, using a gene gun, to mice infected with Leishmania major or Trypanosoma cruzi. Transfer of the IL‐12 gene to susceptible BALB/c mice resulted in regression of lesion size and reduced the number of parasites in draining lymph nodes (LN) at the site of L. major infection. Coincident with these protective effects, the T‐helper type (Th) response shifted towards Th1, as evaluated by cytokine production in vitro and L. major‐specific antibody responses. Protective effects of the IL‐12 gene were also observed in T. cruzi infection. Treatment of BALB/c mice infected with T. cruzi enhanced the production of interferon‐γ (IFN‐γ) by spleen cells, while suppressed production of interleukin‐10 (IL‐10) compared with control mice. Administration of anti‐CD4 or anti‐CD8 monoclonal antibody (mAb) abolished the protective immunity against T. cruzi infection, and treatment with the IL‐12 gene could not restore the resistance in these mice. Mice depleted of natural killer (NK) cells with anti‐asialo GM1 also became susceptible to infection, while the resistance was restored when these mice were treated with the IL‐12 gene. Thus, target cells for the treatment appear to be CD4+ and CD8+ T cells, which are ordinarily activated by NK cells. These results suggest that the transfer of cytokine genes using a gene gun is an effective method for investigating the roles of cytokines and gene therapy in infectious diseases. [ABSTRACT FROM AUTHOR]

Uses non-crossreacting heterologous erythrocyte antigens to explore the mechanisms of antigenic competition in mice. Deficiency in the competition-inducing capacity of chicken erythrocytes; Histological features of the spleens of mice either being prepared for antigenic competition or undergoing competitively suppressed antibody response; Role of the massive proliferation and differentiation of T lymphocytes in causing the antigenic competition.

In an earlier study (Evans, Ishikawa & Estelle 1994, Planta 194, 215-222) we used a video digitizer system to compare the kinetics of auxin action on root elongation in wild-type seedlings and seedlings of auxin response mutants of Arabidopsis thaliana (L.) Heynh. We have since modified the system software to allow determination of elongation on opposite sides of vertical or gravistimulated roots and to allow continuous measurement of the angle of orientation of sequential subsections of the root during the response. We used this technology to compare the patterns of differential growth that generate curvature in roots of the Columbia ecotype and in the mutants axr1-3, axr1-12 and axr2, which show reduced gravitropic responsiveness and reduced sensitivity to inhibition by auxin. The pattern of differential growth during gravitropism differed in roots of wild-type and axr1 seedlings. In wild-type roots, initial curvature resulted from differential inhibition of elongation in the distal elongation zone (DEZ). This was followed by an acceleration of elongation along the top side of the DEZ. In roots of axr1-3, curvature resulted from differential stimulation of elongation whereas in roots of axr1-12 the response was variable. Roots of axr2 did not exhibit gravitropic curvature. The observation that the pattern of differential growth causing curvature is dramatically altered by a change in sensitivity to auxin is consistent with the classical Cholodny-Went theory of gravitropism which maintains that differential growth patterns induced by gravistimulation are mediated primarily by gravi-induced shifts in auxin distribution. The new technology introduced with this report allows automated determination of stimulus response patterns in the small but experimentally popular roots of Arabidopsis. [ABSTRACT FROM AUTHOR]

Intraepithelial T lymphocytes in the small intestine (IEL) consist of αβ T-cell receptor (TCR)-bearing T cells (αβ-IEL) and γδ TCR-bearing T cells (γδ-IEL). Development and cytotytic activation of αβ-IEL sharply attenuate in germ-free (GF) mice fed a natural diet (Nat-GF), but the number and cytotoxicity of γδ-IEL are comparable between conventional (CV) and Nat-GF mice. In this report, we compared the properties of IEL in Nat-GF mice and GF mice fed antigen-minimized diet (AgM-GF mice) of CS7BL/6 strain to evaluate an influence of gut antigenic load on IEL development. Numbers of αβ-IEL and γδ-IEL in AgM-GF mice were less by 1·9- and 1·4-fold than those in Nat-GF mice, respectively. Significant decreases in the proportions of CD4+8-, CD4-8αβ+, and CD4+8+ subsets and a resultant increase in the ratio of CD4-8αα+ subset were evident in αβ-IEL of Nat-GF mice compared with CV mice, but the subset constitution of αβ-IEL was similar between Nat-GF and AgM-GF mice. In contrast, relative composition of γδ-IEL was not different between CV, Nat-GF, and AgM-GF mice. αβ-IEL displayed low cytolytic activity in Nat-GF mice and were almost deprived of their cytotoxicity under the antigen-minimized condition. While γδ-IEL were strongly cytolytic in Nat-GF mice their cytolytic activity was remarkably reduced in AgM-GF mice. These results indicate that γδ-IEL are activated independently of microbial colonization in the gastrointestinal tract but their activation occurs in response to the exogenous antigenic substances other than live micro-organisms. [ABSTRACT FROM AUTHOR]

We demonstrated that γδ T cells contribute to protective immunity against Toxoplasma gondii by inducing the expression of a 65 000 MW heat-shock protein (hsp 65) in host macrophages. Here we examined the role of extrathymic and intrathymic γδ T cells in protective immunity and hsp 65 expression in mice infected with T. gondii, Intrathymic γδ T cells were obtained from severe combined immunodeficiency (SCID) mice grafted with syngeneic fetal thymus (TG-SCID), in which only T cells derived from the donor thymus developed, whereas extrathymic γδ T cells were obtained from nude mice that lack thymus. Extrathymic γδ T cells from T. gondii, infected nude mice differed from intrathymic γδ T cells of infected TG-SCID mice, in terms of Thy1.2 expression and V-region gene usage of T-cell receptor (TCR) γδ. Extrathymic γδ T cells expressed extremely high levels of Thyl.2, and had Vγ7 repertoire but lacked Vγ5,6 and Vδ1,5. On the other hand, intrathymic γδ T cells express intermediate and low levels of Thy1.2. These cells possessed Vγ5,6 and Vδ1,5 but failed to rearrange the Vδ7 gene. Peritoneal macrophages from infected nude mice contained hsp 65, whereas this protein was scarcely expressed in those of infected TG-SCID mice. Transfer of extrathymic, but not of intrathymic γδ T cells to SCID mice enabled their macrophages to express hsp 65. Athymic nude mice were significantly resistant to the infection compared with SCID mice which lack γδ T as well as αβ T cells. The resistance was dependent upon extrathymic γδ T cells, since nude mice depleted of γδ T cells using a corresponding monoclonai antibody became extremely susceptible. These results indicated that extrathymic rather than intrathymic γδ T cells play some crucial roles in protection against T. gondii and in hsp 65 expression. [ABSTRACT FROM AUTHOR]