High-Fat Diet-Induced Diabetic Conditions Exacerbate Cognitive Impairment in a Mouse Model of Alzheimer's Disease Via a Specific Tau Phosphorylation Pattern.

BACKGROUND: Epidemiological evidence has demonstrated a clear association between diabetes mellitus and increased risk of Alzheimer's disease (AD). Cerebral accumulation of phosphorylated tau aggregates, a cardinal neuropathological feature of AD, is associated with neurodegeneration and cognitive decline. Clinical and experimental studies indicate that diabetes mellitus affects the development of tau pathology; however, the underlying molecular mechanisms remain unknown. OBJECTIVE: In the present study, we used a unique diabetic AD mouse model to investigate the changes in tau phosphorylation patterns occurring in the diabetic brain. DESIGN: Tau-transgenic mice were fed a high-fat diet (n = 24) to model diabetes mellitus. These mice developed prominent obesity, severe insulin resistance, and mild hyperglycemia, which led to early-onset neurodegeneration and behavioral impairment associated with the accumulation of hyperphosphorylated tau aggregates. RESULTS: Comprehensive phosphoproteomic analysis revealed a unique tau phosphorylation signature in the brains of mice with diabetic AD. Bioinformatic analysis of the phosphoproteomics data revealed putative tau-related kinases and cell signaling pathways involved in the interaction between diabetes mellitus and AD. CONCLUSION: These findings offer potential novel targets that can be used to develop tau-based therapies and biomarkers for use in AD.

Apomictic parthenogenesis in a parasitoid wasp Meteorus pulchricornis, uncommon in the haplodiploid order Hymenoptera.

Although apomixis is the most common form of parthenogenesis in diplodiploid arthropods, it is uncommon in the haplodiploid insect order Hymenoptera. We found a new type of spontaneous apomixis in the Hymenoptera, completely lacking meiosis and the expulsion of polar bodies in egg maturation division, on the thelytokous strain of a parasitoid wasp Meteorus pulchricornis (Wesmael) (Braconidae, Euphorinae) on pest lepidopteran larvae Spodoptera litura (Fabricius) (Noctuidae). The absence of the meiotic process was consistent with a non-segregation pattern in the offspring of heterozygous females, and no positive evidence was obtained for the induction of thelytoky by any bacterial symbionts. We discuss the conditions that enable the occurrence of such rare cases of apomictic thelytoky in the Hymenoptera, suggesting the significance of fixed heterosis caused by hybridization or polyploidization, symbiosis with bacterial agents, and occasional sex. Our finding will encourage further genetic studies on parasitoid wasps to use asexual lines more wisely for biological control.

Genetic differences and phenotypic plasticity in body size between high- and low-altitude populations of the ground beetle Carabus tosanus.

The body size of a univoltine carabid beetle Carabus tosanus on Shikoku Island, Japan, was clearly smaller in higher-altitude populations (subspecies), which possibly represents incipient speciation. To explore the determinants of altitudinal differences in body size in this species, we studied the degree of phenotypic plasticity by conducting rearing experiments at two constant temperatures and examined genetic differences through interpopulation crosses. At 15 °C, C. tosanus had a longer developmental period and a shorter adult body than at 20 °C. Nevertheless, variation in body size due to temperature effects (phenotypic plasticity) was small compared to the interpopulation differences, which suggests substantial genetic differences between populations (subspecies) at different altitudes. In F(1) offspring from crosses between a low-altitude (subspecies tosanus) and a high-altitude population (subspecies ishizuchianus), adult body length was affected by the genotypes of both parents, with an interaction effect of parental genotype and offspring sex. Further analyses revealed that adult body length was affected by sex-linked factors in addition to autosomal factors. These genetic differences in body size may have resulted from adaptations to different altitudes and may be important for the process of incipient speciation because body size differences could contribute to premating reproductive isolation.

Development and evaluation of 'disaster preparedness' educational programme for pregnant women.

PURPOSE: The objective of this study is the development and evaluation of the usability of an educational programme that teaches disaster preparedness to pregnant women. METHODS: This intervention study examined an intervention group that attended an educational programme and a control group that did not. The subjects were pregnant women in their second trimester. The programme was developed with prior studies and evaluated by self-administered questionnaires that asked about disaster preparedness. The questionnaire was administered twice to the participants in both groups: to the intervention group just before the childbirth class and 1 month after the class, and to the control group at the time of their maternity examination and 1 month afterwards. Two hundred twenty-six members of the intervention group and 262 members of the control group responded to both questionnaires. Of these, 99 of the intervention group and 104 of the control group were primiparous without disaster experience, and the programme was evaluated by comparing these two groups. Effects due to the disaster experience were also analysed within the intervention group. RESULTS: Among primiparous without disaster experience, an intervention effect was found in items concerning awareness modification (five of six items) and behaviour modification (three of seven items). The intervention effect was particularly pronounced in a comparison of primiparous without disaster experience. CONCLUSIONS: An intervention effect was found among the pregnant women who took the programme. In particular, it was statistically significant among primiparous without disaster experience, which suggests that the programme should be shaped to reflect this subject demographic.

[Acute pulmonary embolism after colorectal surgery].

A 84-year-old woman presented with abdominal pain and tarry stools. She was admitted to our hospital, and colonofiberscopy showed type II tumor located cecum. We prevented deep vein thrombosis and acute pulmonary embolism (APE) after abdominal surgery by using the elastic stockings and intermittent pneumatic compression system in operation room. She underwent ileocecal resection and lymphonodi dissection (D2). On 2nd postoperative day, she complained of sudden respiratory distress with loss of consciousness and went into the state of shock. We made the diagnosis of APE after reviewing chest computed tomography and cardiac echo. An emergency atrial and pulmonary thromboembolectomy under cardiopulmonary bypass was performed. We removed the thrombus from right atrium and bilateral main pulmonary artery. After operation, we inserted a temporary vena cava filter into vena cava. We performed the anticoagulant therapy by continuous infusion of heparin with assisting respiration by respirator. The pulmonary artery pressure became steady about 25 approximately 30 mmHg. On 14th postoperative day, we extubated tracheotube. On 40th postoperative day, she could discharge from hospital on foot. Early diagnosis and prompt treatment for APE are important, and we should always keep APE in mind after abdominal surgery.

Cold shock domain protein A represses angiogenesis and lymphangiogenesis via inhibition of serum response element.

Dual-targeted therapy for antiangiogenesis and antilymphangiogenesis represents a potentially effective strategy for the treatment of various malignancies. Therefore, the goal of the present study was to identify genes that encode inhibitors of both angiogenesis and lymphangiogenesis. Using a cDNA library obtained from Lewis lung carcinoma (LL/2), a candidate gene was identified by the evaluation of growth inhibition in aortic and lymphatic endothelial cells (EC) as that coding for the mouse cold shock domain protein A (mCSDA). Overexpression of mCSDA significantly repressed cell proliferation and c-fos promoter activity in aortic, venous and lymphatic ECs. CSDA is a DNA-binding protein that binds to the hypoxia response element (HRE). Furthermore, of importance, we revealed that CSDA could directly bind to the serum response element (SRE) sequence, resulting in the inhibition of SRE activity, which may lead to growth inhibition in ECs. In an LL/2-inoculated mouse model, tumor growth was significantly repressed in an mCSDA-injected group. Histopathological analysis revealed that expression of blood and lymphatic EC markers was significantly decreased in mCSDA-injected groups. In conclusion, these data suggest that expression of CSDA can repress angiogenesis and lymphangiogenesis via direct binding to SRE in addition to HRE.

[Tricuspid valve plasty associated with removal of an infected pacemaker lead: report of a case].

We performed tricuspid valve plasty in a 72-year-old woman with pacemaker lead infection and septicemia. All the infected pacemaker system was removed under cardiopulmonary bypass. Because of advanced adhesion and infection, we needed partial resection and plasty of the tricuspid valve. Postoperative echocardiography revealed only mild tricuspid regurgitation and the recurrence of infection has been avoided. Our technique of valve plasty was useful in a patient with advanced infection of both pacemaker leads and tricuspid valve leaflets.

Rapid diversification of male genitalia and mating strategies in Ohomopterus ground beetles.

We analysed evolutionary diversification and covariation in male genitalia and four mating traits related to sexual selection, i.e. testis size, spermatophore size, copulation duration and post-copulatory guarding duration, in Ohomopterus ground beetles using phylogenetically independent contrasts. Male genital size and mating duration have evolved more rapidly than body size and the other traits studied. Male genital size was negatively correlated with copulation duration, suggesting that elongated male genitalia may enable decreased time investment in a single copulation because it is more effective at facilitating spermatophore deposition. Male genital size was positively correlated with spermatophore size, suggesting coevolution between offensive and defensive male mating tactics because the elongated male genitalia may be advantageous in displacement of rivals' plug-like spermatophores, and decreased mating duration may intensify sperm competition. Thus, the remarkable diversity of male genitalia in Ohomopterus may have been facilitated by the interplay between inter- and intrasexual selection processes.

The genetic basis of interspecific differences in genital morphology of closely related carabid beetles.

Marked diversification of genital morphology is common in internally fertilizing animals. Although sexual selection may be the primary process controlling genital evolution, factors promoting genital evolution are controversial, and the genetic background of genital morphology is poorly understood. We analyzed the genetic basis of species-specific genital morphologies in carabid beetles of the subgenus Ohomopterus (genus Carabus, Carabidae) using two parapatric species with hybrid zones. Biometric analyses on experimental F(1) and backcross populations revealed that inheritance of genital morphology is polygenic. Applying Lande's modification of the Castle-Wright estimator to population means and variances to estimate the minimum number of genes involved, we found that a relatively small number of loci is responsible for species differences in genital morphology. In addition, joint-scaling tests indicated that the additive genetic effect accounts for most interspecific differences in genital traits, but dominance and epistatic genetic effects also play roles. Overall, the genetic basis of male and female genitalia is fairly simple, enabling these traits to respond quickly to selection pressures and to diverge rapidly. Our results provide insight into the diversification of genital morphology in carabid beetles, and will hopefully stimulate further studies on the genetic basis of genitalia, such as mapping of quantitative trait loci affecting species-specific genital morphology.

Attenuation of acid induced oesophagitis in VR-1 deficient mice.

BACKGROUND AND AIMS: Activation of the vanilloid receptor subtype 1 (VR-1) results in release of proinflammatory peptides which initiate an inflammatory cascade known as neurogenic inflammation. We investigated its role in an acute model of surgically induced oesophagitis. METHODS: Oesophagitis was induced by pyloric ligation in wild-type and VR-1 deficient mice. A subset of animals were administered the VR-1 antagonist capsazepine, famotidine, or omeprazole one hour before surgery. Five hours after surgery, myeloperoxidase activity (MPO), histological damage scores, intragastric pH, and immunocytochemical analysis of substance P (SP) receptor endocytosis were determined. RESULTS: Oesophagitis induced knockout mice exhibited significantly lower levels of MPO activity, histological damage scores, and SP receptor endocytosis than wild-type mice. Inflammatory parameters were significantly reduced by acid inhibition and capsazepine in wild-type mice. CONCLUSIONS: We conclude that acute acid induced oesophagitis is reduced in animals lacking VR-1. This suggests that acid induced oesophagitis may act through VR-1 and that inhibition of the receptor may reduce inflammation.

Species status and phylogeography of two closely related Coptolabrus species (Coleoptera: Carabidae) in South Korea inferred from mitochondrial and nuclear gene sequences.

We investigated the species status and intraspecific phylogeography in South Korea of two ground beetle species, Coptolabrus jankowskii and Coptolabrus smaragdinus (Coleoptera: Carabidae), using statistical parsimony networks and nested clade analyses based on sequences from the mitochondrial cytochrome oxidase subunit I (COI) and nuclear phosphoenolpyruvate carboxykinase (PepCK) and wingless (Wg) genes. Although traditional parsimony tree construction generally failed to resolve interspecific relationships and construct biologically meaningful genealogies, analysis using statistical parsimony networks yielded statistically significant inter- and intraspecific genealogical structures. We found that although these two species represent a notable case of trans-species polymorphisms in both mitochondrial and nuclear gene sequences, their status as separate species was evidenced by the nonrandom association between species and nested clades at various nesting levels. The exceptional occurrence of shared identical or very similar COI sequences was considered to be the result of introgressive hybridization. In addition, range expansion and fragmentation events across the Korean Peninsula and adjacent islands were inferred from nested clade phylogeographical analyses. The COI gene revealed the geographical divergence of major eastern and western clades and historical biogeographical events within each major clade, whereas the nuclear PepCK gene, which did not reveal corresponding east-west clades, indicated past fragmentation and range expansion across wide areas that may have been the result of older biogeographical events. Thus, phylogeographical inferences drawn from analyses of mitochondrial and nuclear genes can reveal different and potentially complementary information about phylogeographical processes.

Activation of Cdh1-dependent APC is required for G1 cell cycle arrest and DNA damage-induced G2 checkpoint in vertebrate cells.

Anaphase-promoting complex (APC) is activated by two regulatory proteins, Cdc20 and Cdh1. In yeast and Drosophila, Cdh1-dependent APC (Cdh1-APC) activity targets mitotic cyclins from the end of mitosis to the G1 phase. To investigate the function of Cdh1 in vertebrate cells, we generated clones of chicken DT40 cells disrupted in their Cdh1 loci. Cdh1 was dispensable for viability and cell cycle progression. However, similarly to yeast and Drosophila, loss of Cdh1 induced unscheduled accumulation of mitotic cyclins in G1, resulting in abrogation of G1 arrest caused by treatment with rapamycin, an inducer of p27(Kip1). Further more, we found that Cdh1(-/-) cells fail to maintain DNA damage-induced G2 arrest and that Cdh1-APC is activated by X-irradiation-induced DNA damage. Thus, activation of Cdh1-APC plays a crucial role in both cdk inhibitor-dependent G1 arrest and DNA damage-induced G2 arrest.

Relation of intraoperative flow measurement with postoperative quantitative angiographic assessment of coronary artery bypass grafting.

BACKGROUND: It is critical to evaluate the anastomotic quality of coronary artery bypass grafting (CABG) in the operating room. The aim of this study is to determine the validity of intraoperative flow measurement for predicting the quality of CABG by comparison with the postoperative quantitative angiographic evaluation of the grafts. METHODS: Eighty-two grafts, including 37 internal thoracic arteries, were examined intraoperatively with a transit-time flowmeter. Coronary angiograms were performed 14 +/- 5 days after CABG to quantify the diameters at the toe, heel, and anastomosis proper of the grafts. RESULTS: There were significant differences between patent and nonpatent grafts in all intraoperative flow parameters. However, the only cut-off value to distinguish patent from nonpatent was a fast Fourier transformation (FFT) ratio of 1.0. FFT is the ratio of powers of the fundamental frequency and its first harmonic. Postoperative quantitative angiography indicated that the stenosis was greatest at the heel of the anastomosis. The degree of stenosis at the heel of the anastomosis alone correlated significantly with intraoperative mean flow values. CONCLUSIONS: Fast Fourier transformation analysis of flow measurement may be useful to differentiate patent grafts intraoperatively. Intraoperative flow measurement may predict the most stenotic part of the anastomosis.

A simple method to determine anastomotic quality of coronary artery bypass grafting in the operating room.

Anastomotic quality of coronary artery bypass grafting is directly associated with peri-operative and long-term clinical results. In this study, we investigated a cut-off value for intra-operative flow measurement. This value could be of use to a surgeon in determining the anastomotic quality of grafts. Intra-operative transit-time flow variables (mean flow, pulsatility index, % efficiency, fast Fourier transformation (FFT) of the flow curve) and the 2-week post-operative angiographic findings were examined in 66 coronary artery bypass grafts, including 33 internal thoracic arteries. There were significant differences between patent and non patent grafts in all of the intra-operative flow parameters. Only the FFT ratio, the ratio of powers of the fundamental frequency and its first harmonic, could be utilized as a cut-off value to distinguish patent from non patent grafts. All stenotic or occluded grafts showed an intra-operative FFT ratio of <1.0, while all patent grafts yielded a ratio of >1.0. Based upon these results, we concluded that power spectral analysis of flow measurement might be useful for intra-operative differential diagnosis of the anastomotic quality in coronary artery bypass grafting.

A monoclonal antibody against insect CALNUC recognizes the prooncoprotein EWS specifically in mammalian cells. Immunohistochemical and biochemical studies of the antigen in rat tissues.

A monoclonal antibody against insect CALNUC was shown to recognize an 85-kDa nuclear protein specifically in mammalian cells. Amino acid sequencing of the protein purified from rat liver revealed it to be EWS, a prooncoprotein for Ewing sarcomas and related tumors. Using the antibody, distribution of EWS was studied in rat tissues fixed with 4% paraformaldehyde by immunohistochemical methods. On thaw-fixed cryosections or those of perfusion-fixed tissues, almost all cell nuclei showed the specific staining. In immersion-fixed tissues, the staining unexpectedly disappeared in particular tissues (kidney cortex, liver, etc.), although it was recovered by autoclaving the cryosections. Western blotting also demonstrated the ubiquitous expression of EWS in the tissues. In extracts from the liver, the 85-kDa band rapidly disappeared in a Ca(2+)-dependent manner, but never in the testis. The antigen was very labile in kidney homogenates even without Ca2+. Biochemical studies with digoxigenin-labeled EWS showed that the Ca(2+)-dependent disappearance was associated with upward mobility shifts of EWS. These suggested that EWS was ubiquitously expressed in rat tissues, and that the antigen was masked in particular tissues during the immersion fixation.

The "mini-elephant trunk" technique of distal anastomosis in total arch replacement through a median sternotomy for a distal aortic arch aneurysm.

A median sternotomy is considered to have several advantages over a left thoracotomy as a route for the surgical treatment of a distal aortic arch aneurysm, including less pain and less lung damage. In a median sternotomy, distal anastomosis is such an important problem that we herein present a useful technique to prevent surgical bleeding from it. An invaginated 40-mm-long graft is inserted into the distal aorta, sutured to the aortic wall, unfolded, and anastomosed with a four-limbed tube graft. We applied this "mini-elephant trunk" technique to total arch replacement for both a saccural distal aneurysm, where the distal aorta was transected, and a fusiform aneurysm, where the invaginated graft was sutured by the "inclusion" method. This technique enables a greater surface contact area between the graft and the aortic wall at the distal anastomosis, thus resulting in a reduced risk of bleeding.

Participation of histones and histone-modifying enzymes in cell functions through alterations in chromatin structure.

Alterations in the chromatin structure are preferentially involved in the regulation of cell functions, including gene expression, in eukaryotes. Three types of mechanisms, by which the alterations are caused have been reported: (i) variants of histone subtypes, (ii) chromatin remodeling, and (iii) post-translational modification. This review focuses mainly on the first and third mechanisms, especially on the acetylation of core histones, one of the third mechanisms. Using the gene targeting technique for the DT40 chicken B cell line, we systematically generated a number of mutants, respectively, devoid of particular genes encoding histones and histone deacetylase(s) (HDACs). Most of the H1 and core histone variants should be involved positively or negatively in the transcription regulation of particular genes. Of the chicken HDACs (chHDACs), chHDAC-2 controls the amount of the IgM H-chain at the steps of both transcription and alternative pre-mRNA processing, and chHDAC-3 is essential for cell viability, whereas chHDAC-1 merely affects gene expression in DT40 cells. These results indicate that HDAC family members should participate, in combination with one another, and/or histone acetyltransferase(s) (HATs), in the acetylation of core histones that regulates gene expression through alterations in the chromatin structure.

Leucine zipper motif of chicken histone acetyltransferase-1 is essential for in vivo and in vitro interactions with the p48 subunit of chicken chromatin assembly factor-1.

We cloned cDNA encoding chicken cytoplasmic histone acetyltransferase-1, chHAT-1, comprising 408 amino acids including a putative initiation Met. It exhibits 80.4% identity to the human homolog and possesses a typical leucine zipper motif. The glutathione S:-transferase (GST) pull-down assay, involving truncated and missense mutants of the chicken chromatin assembly factor-1 (chCAF-1)p48, revealed not only that a region (comprising amino acids 376-405 of chCAF-1p48 and containing the seventh WD dipeptide motif) binds to chHAT-1 in vitro, but also that mutation of the motif has no influence on the in vitro interaction. The GST pull-down assay, involving truncated and missense chHAT-1 mutants, established that a region, comprising amino acids 380-408 of chHAT-1 and containing the leucine zipper motif, is required for its in vitro interaction with chCAF-1p48. In addition, mutation of each of four Leu residues in the leucine zipper motif prevents the in vitro interaction. The yeast two-hybrid assay revealed that all four Leu residues within the leucine zipper motif of chHAT-1 are necessary for its in vivo interaction with chCAF-1p48. These results indicate not only that the proper leucine zipper motif of chHAT-1 is essential for its interaction with chCAF-1p48, but also that the propeller structure of chCAF-1p48 expected to act as a platform for protein-protein interactions may not be necessary for this interaction of chHAT-1.

Resolution of perivalvular hematoma of the Freestyle stentless aortic root bioprosthesis implanted with a subcoronary technique.

The modified subcoronary technique is frequently used to implant the Freestyle aortic root bioprosthesis because of its ease. This technique is primarily associated with hematoma in the potential space between the prosthetic and native aortic walls. We report a case of resolution of perivalvular hematoma around the Freestyle valve 6 months after implantation in a patient with aneurysm of the noncoronary sinus of Valsalva. During follow-up, the patient underwent no significant changes in pressure gradient or degree of regurgitation. Although long-term results are not yet known, the subcoronary technique may be a feasible alternative for patients with aneurysms in the sinus of Valsalva to exclude it, unless the sinotubular junction and aortic annulus are intact.