Development of a prognostic risk score to predict early mortality in incident elderly Japanese hemodialysis patients

by Hirokazu Okada, Atsushi Ono, Koji Tomori, Tsutomu Inoue, Norio Hanafusa, Ken Sakai, Ichiei Narita, Toshiki Moriyama, Yoshitaka Isaka, Kei Fukami, Seiji Itano, Eiichiro Kanda, Naoki Kashihara

Background

Information of short-term prognosis after hemodialysis (HD) introduction is important for elderly patients with chronic kidney disease (CKD) and their families choosing a modality of renal replacement therapy. Therefore, we developed a risk score to predict early mortality in incident elderly Japanese hemodialysis patients.

Materials and methods

We analyzed data of incident elderly HD patients from a nationwide cohort study of the Japanese Society for Dialysis Therapy Renal Data Registry (JRDR) to develop a prognostic risk score. Candidate risk factors for early death within 1 year was evaluated using multivariate logistic regression analysis. The risk score was developed by summing up points derived from parameter estimate values of independent risk factors. The association between risk score and early death was tested using Cox proportional hazards models. This risk score was validated twice by using an internal validation cohort derived from the JRDR and an external validation cohort collected for this study.

Results

Using the development cohort (n = 2,000), nine risk factors were retained in the risk score: older age (>85), yes = 2, no = 0; sex, male = 2, female = 0; lower body mass index (2.0 mg/dL), yes = 2, no = 0. In the internal and external validation cohorts (n = 739, 140, respectively), the medium- and high-risk groups (total score, 6 to 10 and 11 or more, respectively) showed significantly higher risk of early death than the low-risk group (total score, 0 to 5) (p Conclusion

We developed a prognostic risk score predicting early death within 1 year in incident elderly Japanese HD patients, which may help detect elderly patients with a high-risk of early death after HD introduction.

Inter- and intra-rater reproducibility of quantitative T1 measurement using semiautomatic region of interest placement in myometrium

by Sadahiro Nakagawa, Takahiro Uno, Shunta Ishitoya, Eriko Takabayashi, Akiko Oya, Wakako Kubota, Atsutaka Okizaki

Purpose

This study aimed to investigate the inter- and intraobserver reproducibility of quantitative T1 (qT1) measurements using manual and semiautomatic region of interest (ROI) placements. We hypothesized the usefulness of the semiautomatic method, which utilizes a three-dimensional (3D) anatomical relationship between the myometrium and other tissues, for minimizing ROI placement variation, thereby improving qT1 reproducibility compared to the manual approach. The semiautomatic approach, which considered anatomical relationships, was expected to enhance reproducibility by reducing ROI placement variabilities.

Materials and methods

This study recruited 23 healthy female volunteers. Data with variable flip angle (VFA) and inversion recovery were acquired using 3D-spoiled gradient echo and spin echo sequences, respectively. T1 maps were generated with VFA. Manual and semiautomatic ROI placements were independently conducted. Mean qT1 values were calculated from the T1 maps using the corresponding pixel values of the myometrial ROI. Inter- and intraobserver reproducibility of qT1 values was investigated. The inter- and intraobserver reproducibility of qT1 values was evaluated by calculating the coefficient of variation (CoV). Further, reproducibility was evaluated with inter- and intraobserver errors and intraclass correlation coefficients (ICCs). Bland–Altman analysis was utilized to compare the results, estimate bias, and determine the limits of agreement.

Results

The mean inter- and intraobserver CoV of the qT1 values for semiautomatic ROI placement was significantly lower than those for manual ROI placement (p p p p Conclusion

Semiautomatic ROI placement demonstrated high reproducibility of qT1 measurements compared with manual methods. Semiautomatic ROI placement may be useful for evaluating uterine qT1 with high reproducibility.

Non-fibril form but not fibril form of human islet amyloid polypeptide 8–20 changes brain functions in mice

by Hinaho Suginoma, Ryuji Owada, Akiko Katano-Toki, Ayaka Mori, Jun Fujioka, Kazuhiro Nakamura

Whether fibril formation increases or decreases cytotoxicity remains unclear. Aggregation of human islet amyloid polypeptide (hIAPP), a pivotal regulator of glucose homeostasis, impairs the function and viability of pancreatic β cells. Evidence suggests that low-order oligomers of hIAPP are more toxic to β cells than fibril. However, it remains unclear whether non-fibril form of hIAPP specifically alters brain functions. This study produced fibril and non-fibril forms from a single hIAPP 8–20 peptide. The non-fibril form-injected mice showed changes in spontaneous motor activities, preference for location in the open field and social behavior. In contrast, the fibril-injected mice showed no changes in these behavioral tests. In line with the behavioral changes, the non-fibril form led to impaired neurite outgrowth of cultured neuron-like cells and the loss of neurons in the mouse hippocampus. These findings suggest that non-fibril form but not fibril form of hIAPP changes brain functions.

Association between physical performance and bone mass in community-dwelling postmenopausal Japanese women: The Unzen study

by Masahiro Suiko, Satoshi Mizukami, Kazuhiko Arima, Hiroki Nakashima, Takayuki Nishimura, Yoshihito Tomita, Yasuyo Abe, Natsumi Tanaka, Yuzo Honda, Michiko Kojima, Tetsuji Okawachi, Maiko Hasegawa, Youko Sou, Ritsu Tsujimoto, Mitsuo Kanagae, Makoto Osaki, Kiyoshi Aoyagi

Background

Low bone mass is an independent risk factor for osteoporotic fractures. We examined the association between physical performance and bone mass using quantitative ultrasound in community-dwelling postmenopausal Japanese women.

Methods

We conducted a cross-sectional study on 524 community-dwelling postmenopausal Japanese women who were not being administered osteoporosis medications. Physical performance was assessed on the basis of grip strength, chair stand time, and functional reach. The stiffness index was measured as a quantitative ultrasound parameter for heel bone mass.

Results

Physical performance, assessed by grip strength, chair stand time, and functional reach, and the stiffness index significantly decreased with age (both p Conclusions

Physical performance was significantly associated with heel bone mass in community-dwelling postmenopausal Japanese women.

Asymmetric and symmetric protein arginine methylation in methionine-addicted human cancer cells

by Ashley G. Holtz, Troy L. Lowe, Yusuke Aoki, Yutaro Kubota, Robert M. Hoffman, Steven G. Clarke

The methionine addiction of cancer cells is known as the Hoffman effect. While non-cancer cells in culture can utilize homocysteine in place of methionine for cellular growth, most cancer cells require exogenous methionine for proliferation. It has been suggested that a biochemical basis of this effect is the increased utilization of methionine for S-adenosylmethionine, the major methyl donor for a variety of cellular methyltransferases. Recent studies have pointed to the role of S-adenosylmethionine-dependent protein arginine methyltransferases (PRMTs) in cell proliferation and cancer. To further understand the biochemical basis of the methionine addiction of cancer cells, we compared protein arginine methylation in two previously described isogenic cell lines, a methionine-addicted 143B human osteosarcoma cell line and its less methionine-dependent revertant. Previous work showed that the revertant cells were significantly less malignant than the parental cells. In the present study, we utilized antibodies to detect the asymmetric dimethylarginine (ADMA) and symmetric dimethylarginine (SDMA) products of PRMTs in polypeptides from cellular extracts and purified histone preparations of these cell lines fractionated by SDS-PAGE. Importantly, we observed little to no differences in the banding patterns of ADMA- and SDMA-containing species between the osteosarcoma parental and revertant cell lines. Furthermore, enzymatic activity assays using S-adenosyl-ʟ-[methyl-³H] methionine, recombinantly purified PRMT enzymes, cell lysates, and specific PRMT inhibitors revealed no major differences in radiolabeled polypeptides on SDS-PAGE gels. Taken together, these results suggest that changes in protein arginine methylation may not be major contributors to the Hoffman effect and that other consequences of methionine addiction may be more important in the metastasis and malignancy of osteosarcoma and potentially other cancers.

Hydrogen attenuates endothelial glycocalyx damage associated with partial cardiopulmonary bypass in rats

by Hiroki Iwata, Takasumi Katoh, Sang Kien Truong, Tsunehisa Sato, Shingo Kawashima, Soichiro Mimuro, Yoshiki Nakajima

Cardiopulmonary bypass (CPB) causes systemic inflammation and endothelial glycocalyx damage. Hydrogen has anti-oxidant and anti-inflammatory properties; therefore, we hypothesized that hydrogen would alleviate endothelial glycocalyx damage caused by CPB. Twenty-eight male Sprague–Dawley rats were randomly divided into four groups (n = 7 per group), as follows: sham, control, 2% hydrogen, and 4% hydrogen. The rats were subjected to 90 minutes of partial CPB followed by 120 minutes of observation. In the hydrogen groups, hydrogen was administered via the ventilator and artificial lung during CPB, and via the ventilator for 60 minutes after CPB. After observation, blood collection, lung extraction, and perfusion fixation were performed, and the heart, lung, and brain endothelial glycocalyx thickness was measured by electron microscopy. The serum syndecan-1 concentration, a glycocalyx component, in the 4% hydrogen group (5.7 ± 4.4 pg/mL) was lower than in the control (19.5 ± 6.6 pg/mL) and 2% hydrogen (19.8 ± 5.0 pg/mL) groups (P P = 0.999). The endothelial glycocalyces of the heart and lung in the 4% hydrogen group were thicker than in the control group. The 4% hydrogen group had lower inflammatory cytokine concentrations (interleukin-1β and tumor necrosis factor-α) in serum and lung tissue, as well as a lower serum malondialdehyde concentration, than the control group. The 2% hydrogen group showed no significant difference in the serum syndecan-1 concentration compared with the control group. However, non-significant decreases in serum and lung tissue inflammatory cytokine concentrations, as well as in serum malondialdehyde concentration, were observed. Administration of 4% hydrogen via artificial and autologous lungs attenuated endothelial glycocalyx damage caused by partial CPB in rats, which might be mediated by the anti-inflammatory and anti-oxidant properties of hydrogen.

The effect of a brinzolamide/brimonidine fixed combination on optic nerve head blood flow in rabbits

by Nana Takahashi, Kota Sato, Naoki Kiyota, Mai Yamazaki, Eriko Kunikane, Toru Nakazawa

Purpose

The purpose of this study was to investigate the effect of a 1% brinzolamide and 0.1% brimonidine fixed combination (BBFC) on ONH blood flow (BF) in rabbits.

Methods

A crossover study was conducted on pigmented rabbits; a physiological saline solution, brinzolamide, or BBFC was administered for eight days. ONH BF, intraocular pressure (IOP) and systemic parameters were measured before the eighth day’s first dose and at 6, 9, 12, and 14 hours after the dose. ONH BF was assessed using laser speckle flowgraphy, and mean blur rate (MBR) values were calculated. The percentage against baseline of each parameter was calculated, and intergroup comparisons were performed at each time point.

Results

There were no significant differences in the percentage change in systemic parameters. At 6 hours after administration, the BBFC group showed a significantly higher percentage change in large vessel area-MBR (%MV) compared to the control group (98.6±16.8%MV vs. 81.3±7.9%MV, P = 0.03). On the other hand, the brinzolamide group did not show a significant difference. Both the brinzolamide and BBFC groups had significantly lower percentage change in IOP (%IOP) compared to the control group (90.6±5.0%IOP, 93.3±2.9%IOP, and 99.2±1.7%IOP, respectively, P Conclusion

BBFC effectively reduces IOP and mitigates diurnal fluctuation-induced decreases in ONH BF.

Cumulative violence exposures among men who have sex with men living with HIV in India: Psychosocial correlates of HIV care continuum outcomes

by Bushra Sabri, Chakra Budhathoki, Allison M. McFall, Shruti H. Mehta, David D. Celentano, Sunil S. Solomon, Aylur K. Srikrishnan, Santhanam Anand, Canjeevaram K. Vasudevan, Gregory M. Lucas

Lifetime exposures to violence among men who have sex with men (MSM) are associated with multiple psychosocial health risks and can affect engagement and outcomes of HIV treatment. This study a) explored relationships between levels of exposures to violence and HIV care continuum outcomes among MSM living with HIV in India, and b) identified psychosocial correlates of HIV care continuum outcomes among MSM living with HIV and those with lifetime cumulative exposures to violence (CVE). CVE referred to exposures to violence in both childhood and adulthood. This cross-sectional analysis used survey data collected between August 2016 and May 2017 from 1763 men who have sex with men living with HIV across 10 cities in India, using respondent-driven sampling. We found that higher levels of violence exposure were significantly associated with lower awareness of HIV positive status, and lower likelihood of initiating antiretroviral therapy. Compared with MSM living with HIV that had no CVE, those with CVE were more likely to report perpetration of interpersonal violence, alcohol misuse, depressive symptoms, and HIV transmission risk behaviors and to have two to four co-occurring psychosocial problems. In multivariable analysis with the subset of MSM with CVE, psychosocial correlates significantly associated with at least one HIV care continuum outcome were HIV transmission risk behaviors, perpetration of interpersonal violence, depression, and alcohol misuse. The findings highlight the need for integrating care for lifetime violence exposures and associated behavioral problems in HIV care settings for men who have sex with men living with HIV in India.