Large-Scale Sediment Inflow and Bed-Variation from 12th Typhoon (2011) in the Asahi River Basin

Sediment Transport and Morphodynamic

Tribological properties of nanosized calcium carbonate filled polyamide 66 nanocomposites

For the purpose of developing high performance tribomaterials for mechanical sliding parts such as gears, bearings and so on, nanosized calcium carbonate (nano-CaCO3) tilled polyamide 66 (PA66) nanocomposites were investigated. The nano-CaCO3 was a kind of precipitated (colloid typed) CaCO3, and its average particle size was 40, 80 and 150 nm. Surface treatment was performed by fatty acid on the nano-CaCO3 and its volume fraction in the nanocomposite was varied from 1 to 20vol.%. These nanocomposites were melt-mixed by a twin screw extruder and injection-molded. Tribological properties were measured by two types of sliding wear testers such as ring-on-plate type and ball-on-plate type one under dry condition. The counterface, worn surface and wear debris were observed by digital microscope and scanning electron microscope. It was found that the nano-CaCO3 has a good effect on the tribological properties, although the effect on the frictional coefficient and specific wear rate is differed by the volume fraction and the type of sliding wear modes. This is attributed to the change of wear mechanisms, which is the change of form of the transfer films on the counterface and the size of wear debris. It follows from these results that PA66/nano-CaCO3 nanocomposites may be possible to be the high performance tribomaterials

Bcl2 Deficiency Activates FoxO through Akt Inactivation and Accelerates Osteoblast Differentiation

Osteoblast apoptosis plays an important role in bone development and maintenance, and is in part responsible for osteoporosis in sex steroid deficiency, glucocorticoid excess, and aging. Although Bcl2 subfamily proteins, including Bcl2 and Bcl-XL, inhibit apoptosis, the physiological significance of Bcl2 in osteoblast differentiation has not been fully elucidated. To investigate this, we examined Bcl2-deficient (Bcl2(-/-)) mice. In Bcl2(-/-) mice, bromodeoxyuridine (BrdU)-positive osteoblasts were reduced in number, while terminal deoxynucleotidyl transferase-mediated dUTP nick end-labeling (TUNEL)-positive osteoblasts were increased. Unexpectedly, osteoblast differentiation was accelerated in Bcl2(-/-) mice as shown by the early appearance of osteocalcin-positive osteoblasts. Osteoblast differentiation was also accelerated in vitro when primary osteoblasts were seeded at a high concentration to minimize the reduction of the cell density by apoptosis during culture. FoxO transcription factors, whose activities are negatively regulated through the phosphorylation by Akt, play important roles in multiple cell events, including proliferation, death, differentiation, longevity, and stress response. Expressions of FasL, Gadd45a, and Bim, which are regulated by FoxOs, were upregulated; the expression and activity of FoxOs were enhanced; and the phosphorylation of Akt and that of FoxO1 and FoxO3a by Akt were reduced in Bcl2(-/-) calvariae. Further, the levels of p53 mRNA and protein were increased, and the expression of p53-target genes, Pten and Igfbp3 whose proteins inhibit Akt activation, was upregulated in Bcl2(-/-) calvariae. However, Pten but not Igfbp3 was upregulated in Bcl2(-/-) primary osteoblasts, and p53 induced Pten but not Igfbp3 in vitro. Silencing of either FoxO1 or FoxO3a inhibited and constitutively-active FoxO3a enhanced osteoblast differentiation. These findings suggest that Bcl2 deficiency induces and activates FoxOs through Akt inactivation, at least in part, by upregulating Pten expression through p53 in osteoblasts, and that the enhanced expression and activities of FoxOs may be one of the causes of accelerated osteoblast differentiation in Bcl2(-/-) mice

Effect of ipragliflozin on carotid intima-media thickness in type 2 diabetes patients

Aims To examine the effects of a 24-month treatment with ipragliflozin on carotid intima-media thickness (IMT) in type 2 diabetes patients. Methods and results In this multicenter, prospective, randomized, open-label, and blinded-endpoint investigator-initiated clinical trial, adults with type 2 diabetes and haemoglobin A1C (HbA1c) of 6.0–10.0% (42–86 mmol/mol) were randomized equally to ipragliflozin (50 mg daily) and non-sodium-glucose cotransporter-2 (SGLT2) inhibitor use of standard-care (control group) for type 2 diabetes and were followed-up to 24 months. The primary endpoint was the change in mean common carotid artery IMT (CCA-IMT) from baseline to 24 months. A total of 482 patients were equally allocated to the ipragliflozin (N = 241) and control (N = 241) groups, and 464 patients (median age 68 years, female 31.7%, median type 2 diabetes duration 8 years, median HbA1c 7.3%) were included in the analyses. For the primary endpoint, the changes in the mean CCA-IMT from baseline to 24 months were 0.0013 [95% confidence interval (CI), −0.0155–0.0182] mm and 0.0015 (95% CI, −0.0155–0.0184) mm in the ipragliflozin and control groups, respectively, with an estimated group difference (ipragliflozin-control) of −0.0001 mm (95% CI, −0.0191–0.0189; P = 0.989). A group difference in HbA1c change at 24 months was also non-significant between the treatment groups [−0.1% (95% CI, −0.2–0.1); P = 0.359]. Conclusion Twenty-four months of ipragliflozin treatment did not affect carotid IMT status in patients with type 2 diabetes recruited in the PROTECT study, relative to the non-SGLT2 inhibitor-use standard care for type 2 diabetes

A Case of Nager Syndrome Diagnosed Before Birth

Nager syndrome is a rare disease involving severe micrognathia and upper limb shortening. In this report, we describe a case in which micrognathia of the fetus was suspected based on the observation of upper limb shortening during detailed B mode and 3D/4D ultrasonographic observation, and combined fetal MRI and 3D-CT led to a prenatal diagnosis of Nager syndrome. Upon birth, because severe micrognathia caused airway obstruction and made it difficult to spread the larynx for intubation, effective ventilation could not be carried out and a tracheostomy was necessary. Since a differential diagnosis of Nager syndrome can be made based on the fact that micrognathia typically co-occurs with upper limb shortening, it is possible to diagnose the disease before birth and prepare for life-saving measures accordingly

Incidence of orthostatic hypotension and cardiovascular response to postoperative early mobilization in patients undergoing cardiothoracic and abdominal surgery

Background: In cardiothoracic and abdominal surgery, postoperative complications remain major clinical problems. Early mobilization has been widely practiced and is an important component in preventing complications, including orthostatic hypotension (OH) during postoperative management. We investigated cardiovascular response during early mobilization and the incidence of OH after cardiothoracic and abdominal surgery. Methods: In this prospective observational study, we consecutively analyzed data from 495 patients who underwent elective cardiothoracic and abdominal surgery. We examined the incidence of OH, and the independent risk factors associated with OH during early mobilization after major surgery. Multivariate logistic regression was performed using various characteristics of patients to identify OH-related independent factors. Results: OH was observed in 191 (39%) of 495 patients. The incidence of OH in cardiac, thoracic, and abdominal groups was 39 (33%) of 119, 95 (46%) of 208, and 57 (34%) of 168 patients, respectively. Male sex (OR 1.538; p = 0.03) and epidural anesthesia (OR 2.906; p < 0.001) were independently associated with OH on multivariate analysis. Conclusions: These results demonstrate that approximately 40% patients experience OH during early mobilization aftercardiothoracic and abdominal surgery. Sex was identified as an independent factor for OH during early mobilization after all three types of surgeries, while epidural anesthesia was only identified after thoracic surgery. Therefore, the frequent occurrence of OH during postoperative early mobilization should be recognized

DOCK2 is involved in the host genetics and biology of severe COVID-19

「コロナ制圧タスクフォース」COVID-19疾患感受性遺伝子DOCK2の重症化機序を解明 --アジア最大のバイオレポジトリーでCOVID-19の治療標的を発見--. 京都大学プレスリリース. 2022-08-10.Identifying the host genetic factors underlying severe COVID-19 is an emerging challenge. Here we conducted a genome-wide association study (GWAS) involving 2, 393 cases of COVID-19 in a cohort of Japanese individuals collected during the initial waves of the pandemic, with 3, 289 unaffected controls. We identified a variant on chromosome 5 at 5q35 (rs60200309-A), close to the dedicator of cytokinesis 2 gene (DOCK2), which was associated with severe COVID-19 in patients less than 65 years of age. This risk allele was prevalent in East Asian individuals but rare in Europeans, highlighting the value of genome-wide association studies in non-European populations. RNA-sequencing analysis of 473 bulk peripheral blood samples identified decreased expression of DOCK2 associated with the risk allele in these younger patients. DOCK2 expression was suppressed in patients with severe cases of COVID-19. Single-cell RNA-sequencing analysis (n = 61 individuals) identified cell-type-specific downregulation of DOCK2 and a COVID-19-specific decreasing effect of the risk allele on DOCK2 expression in non-classical monocytes. Immunohistochemistry of lung specimens from patients with severe COVID-19 pneumonia showed suppressed DOCK2 expression. Moreover, inhibition of DOCK2 function with CPYPP increased the severity of pneumonia in a Syrian hamster model of SARS-CoV-2 infection, characterized by weight loss, lung oedema, enhanced viral loads, impaired macrophage recruitment and dysregulated type I interferon responses. We conclude that DOCK2 has an important role in the host immune response to SARS-CoV-2 infection and the development of severe COVID-19, and could be further explored as a potential biomarker and/or therapeutic target