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Abstract Background In Japan dialyzers are classified as type I, II, III, IV, or V on the basis of the β 2-microglobulin clearance. In 2023, Type V dialyzers were defined as super high-flux membrane dialyzers. Herein, we investigate the association between dialyzer type and mortality. Methods A cohort study was conducted using the Japanese Society for Dialysis Therapy Renal Data Registry database from 31 December 2017, to 31 December 2019. We enrolled 181,879 patients on hemodialysis who were divided into type I–V groups per the Japanese classification. We assessed the associations of each group with 2-year all-cause mortality using Cox proportional hazard models. Furthermore, propensity score matching analysis was performed. Results By the end of 2019, 34,196 patients (18.8%) had died. The hazard ratio (95% confidence interval) was significantly higher in the type I (1.25 [1.12–1.39]), type II (1.21 [1.13–1.31]), and type III (1.07 [1.02–1.13]) groups and significantly lower in the type V group (0.86 [0.80–0.92] P

Abstract Dialyzers are classified into five types based on their β2-microglobulin clearance rate and albumin sieving coefficient: Ia, Ib, IIa, and IIb. In addition, a new classification system introduced a type S dialyzer. However, limited information is available regarding the impact of dialyzer type on patient outcomes. A cohort study was conducted using data from the Japanese Society for Dialysis Therapy Renal Data Registry database. Total 181,804 patients on hemodialysis (HD) were included in the study, categorized into four groups (type Ia, IIa, IIb, and S). The associations between each group and two-year all-cause mortality were assessed using Cox proportional hazard models. Furthermore, propensity score-matching analysis was performed. By the end of 2019, 34,185 patients on dialysis had died. After adjusting for all confounders, the risk for all-cause mortality was significantly lower in the type IIa, and S groups than in the type Ia group. These significant findings were consistent after propensity score matching. In conclusion, our findings suggest that super high-flux dialyzers, with a β2-microglobulin clearance of ≥ 70 mL/min, may be beneficial for patients on HD, regardless of their albumin sieving coefficient. In addition, type S dialyzers may be beneficial for elderly and malnourished patients on dialysis. Trial registration number: UMIN000018641

Abstract Background Approximately 16.4% of patients on hemodialysis (HD) in Japan are treated with intermittent infusion hemodiafiltration (I-HDF). However, large-scale data on clinical outcomes with this modality are lacking. This study aimed to compare the outcomes of I-HDF with those of conventional HD. Methods A cohort study was conducted using the Japanese Society for Dialysis Therapy Renal Data Registry database from December 31, 2017 to December 31, 2019. The subjects were 210,574 patients on maintenance HD. The exposure of interest was I-HDF treatment versus conventional HD. The I-HDF group was divided into two subgroups based on substitution: low-volume (

Abstract Background The 2020 Japanese Society for Dialysis Therapy Renal Data Registry (JRDR) annual survey was sent to 4493 dialysis facilities in Japan. Methods Questionnaires were sent to all facilities that provide patients with dialysis therapy in Japan. Data were collected and compiled to form cross-sectional results of renal replacement therapy from various aspects. Results In total, 4437 facilities (98.8%) responded to the facility questionnaire and 4271 (95.1%) responded to the patient questionnaire. The number of chronic dialysis patients in Japan continues to increase every year, reaching 347,671 at the end of 2020 and giving a prevalence rate of 2754 patients per million population. The mean age was 69.40 years. Diabetic nephropathy was the most common primary disease among the prevalent dialysis patients (39.5%), followed by chronic glomerulonephritis (25.3%) and nephrosclerosis (12.1%). There were 40,744 incident dialysis patients during 2020, representing a decrease of 141 from 2019. The average age of patients on dialysis was 70.88 years, with diabetic nephropathy being the most common underlying disease (40.7%) second most common was nephrosclerosis (17.5%), which was unchanged from the previous year and surpassed chronic glomerulonephritis (15.0%). There were 34,414 patient deaths in 2020; the crude mortality rate was 9.9%. The main causes of death were heart failure (22.4%), infection (21.5%), and malignancy (9.0%), which were almost the same as the percentages for the previous year. Since 2012, the number of patients treated by hemodiafiltration has increased rapidly; in 2020, the number of patients on this modality was 163,825, accounting for 47.1% of all patients on maintenance dialysis. The number of patients on peritoneal dialysis has been on the rise since 2017, reaching 10,338 in 2020; 20.8% of whom received combined therapy with hemodialysis or hemodiafiltration, showing no change from the previous year. A total of 751 patients were on home hemodialysis at the end of 2020, representing a decrease of 9 from the end of 2018. In 2020, coronavirus disease 2019 (COVID-19) infection and malignancy were added as new items in the survey. Continuing on from the 2019 survey, history of kidney donation for a living-donor transplant was investigated. Conclusions Present issues and challenges in renal replacement therapy were identified in the responses to the new questionnaire items included in this survey. A more detailed evaluation with adjustment for patient background factors should clarify the characteristics of the underlying diseases and conditions in dialysis patients. Trial registration The JRDR was approved by the Japanese Society for Dialysis Therapy ethics committee. It was registered in the University Hospital Medical Information Network (UMIN) Clinical Trials Registry on 10 September 2020 and in the UMIN clinical trials registration system (UMIN000018641).

Abstract Background The Japanese Society for Dialysis Therapy is conducting the survey annually since 1968. The results provide a comprehensive picture of dialysis therapy in Japan. The survey for the year 2019 was performed as of December 2019. Methods Questionnaires were sent to all facilities that provide patients with dialysis therapy in Japan as an Excel file. Data were collected and compiled to form cross-sectional results of dialysis therapy from various aspects. Results At the end of 2019, the annual survey of the Japanese Society for Dialysis Therapy Renal Data Registry (JRDR) was conducted at 4487 dialysis facilities, of which 4411 facilities (98.3%) responded to the facility survey and 4238 facilities (94.5%) responded to the patient survey. The number of chronic dialysis patients in Japan continues to increase every year; it reached 344,640 at the end of 2019, and the prevalence ratio of dialysis patients was 2732 per million population. In the patient survey, the mean age of prevalent dialysis patients was 69.09 years. The most prevalent primary disease among prevalent dialysis patients was diabetic nephropathy (39.1%), followed by chronic glomerulonephritis (25.7%) and nephrosclerosis (11.1%). In 2019, there were 40,885 new patients on dialysis, an increase of 417 over 2018. The average age of incident dialysis patients was 70.42 years, and diabetic nephropathy (41.6%) was the most common cause. The second cause was nephrosclerosis, followed by glomerulonephritis. As 34,642 patients passed away in 2019, the crude mortality rate for the year was 10.1%. Heart failure (22.7%), infectious disease (21.5%), and malignancy (8.7%) were the three leading causes of death. Since 2012, the number of patients treated by hemodiafiltration (HDF) has increased substantially. The figure reached 144,686 by year's end, representing 42.0% of all dialysis patients. In 2019, the number of peritoneal dialysis (PD) patients was 9,920, a small rise from 2017. 19.2% of PD patients also received hemodialysis (HD) or HDF to compensate for the reduction in dialysis dosage or in fluid removal by PD alone (hybrid therapy). At the end of 2019, 760 patients received home HD therapy, an increase of 40 from 2018. In 2019, a detailed survey was conducted on the current status of CKD-MBD treatment, 10 years after the previous survey in 2009. The clinical efficacy of newly released medications during this time period and the impact of the 2012 revisions to the CKD-MBD guidelines require further investigation. These analyses would serve as the foundation for the next revision of the CKD-MBD guidelines and may reveal deeper therapeutic insights regarding CKD-MBD. Conclusions The results obtained by the survey revealed the comprehensive practice patterns of dialysis therapy and served as a basis for future guidelines. Trial registration: JRDR was approved by the ethics committee of JSDT (approval number 1–5) and registered in the "University hospital Medical Information Network (UMIN) Clinical Trials Registry" on 10th September 2019 with a clinical trial ID of UMIN000018641. https://upload.umin.ac.jp/cgi-bin/ctr/ctr_view_reg.cgi?recptno=R000021578 (Accessed 20 November 2020).

This paper presents a case study of the design, fabrication, and evaluation of an automotive rear-frame model made of variable axial composites (VAC), using a tailored fiber placement (TFP) technique. Conventionally, the design of a three-dimensional complex VAC structure places significant demands on mechanical engineering expertise (for anisotropic structural design) and on man-hours (for fiber-path CAD). The proposed methods facilitate the design of complex VAC structures with significantly reduced manpower requirements. A computational design method, anisotropic topology optimization, was used to create the base design. The fiber paths on the preform surfaces were generated using a Turing pattern algorithm (based on optimized fiber orientation distributions) subsequent to designing developable three-dimensional surfaces to fill the interior of the target structure. The preforms were fabricated using a computer numerical control (CNC) embroidery machine by stitching the raw fiber tow onto the base fabric in accordance with the generated fiber path data. After stacking the preforms in the mold, they were formed using vacuum-assisted resin-transfer molding (VaRTM). The static stiffness of the prototype was evaluated experimentally, and the results were compared with numerical simulations. This study demonstrates the potential for achieving further weight reduction in large-scale 3D structures by combining innovative computational design techniques with advanced fabrication methods.

Background and objectives Intensity-modulated radiation therapy (IMRT) helps achieve good radiation dose conformity and precise dose evaluation. We conducted a single-centre prospective study to assess the safety and feasibility of total body irradiation with IMRT (IMRT-TBI) using helical tomotherapy in allogeneic haematopoietic stem cell transplantation (allo-HSCT).Patients and methods Thirty-nine adult patients with haematological malignancy (acute lymphoblastic leukaemia [n = 21], chronic myeloid leukaemia [n = 6], mixed phenotype acute leukaemia [n = 5], acute myeloid leukaemia [n = 4], and malignant lymphoma [n = 3]) who received 12 Gy IMRT-TBI were enrolled with a median follow-up of 934.5 (range, 617–1254) d. At the time of transplantation, 33 patients (85%) achieved complete remission. The conditioning regimen used IMRT-TBI (12 Gy in 6 fractions twice daily, for 3 d) and cyclophosphamide (60 mg/kg/d, for 2 d), seven patients were combined with cytarabine, and five with etoposide. We set dose constraints for the lungs, kidneys and lens as the organs at risk.Results The mean doses for the lungs and kidneys were 7.50 and 9.11 Gy, respectively. The mean maximum dose for the lens (right/left) was 5.75/5.87 Gy. The 2-year overall survival (OS), disease-free survival (DFS), cumulative incidence of relapse (CIR) and non-relapse mortality (NRM) were 69, 64, 18 and 18%, respectively. Thirty-six patients developed early adverse events (AEs) (including four patients with Grade 3/4 toxicities), most of which were reversible oral mucositis and may partially have been related to IMRT-TBI. However, the incidence of toxicity was comparable to conventional TBI-based conditioning transplantation. None of the patients developed primary graft failure, or Grade III–IV acute graft-versus-host disease (GVHD). In late complications, chronic kidney disease was observed in six patients, a lower incidence compared to conventional TBI-based conditioning transplantation. No radiation pneumonitis or cataracts were observed in any of the patients.Conclusions IMRT-TBI is safe and feasible for haematological malignancies with acceptable clinical outcomes.KEY MESSAGESIMRT-TBI-helical tomotherapy aids in accurate dose calculation and conformity.It could be used without any considerable increase in the rate of TBI-related AEs.Allo-HSCT with IMRT-TBI may be an alternative to conventional TBI for clinical use.

Abstract Late-onset noninfectious pulmonary complications (LONIPC) are a major cause of morbidity and mortality after allogeneic hematopoietic stem cell transplantation (HSCT). However, the clinical impact of lung function deterioration itself in long-term adult survivors of HSCT remains to be fully investigated. This retrospective, longitudinal study aimed to investigate pulmonary function following HSCT in terms of its change and the clinical significance of its decline. We examined 167 patients who survived for at least 2 years without relapse. The median follow-up period was 10.3 years. A linear mixed-effects model showed that the slope of pulmonary function tests values, including percent vital capacity (%VC), percent forced expiratory volume in one second (%FEV1), and FEV1/forced VC ratio (FEV1%), decreased over time. The cumulative incidence of newly obstructive and restrictive lung function impairment (LFI) at 10 years was 15.7% and 19.5%, respectively. Restrictive LFI was a significant, independent risk factor for overall survival (hazard ratio 7.11, P = 0.007) and non-relapse mortality (hazard ratio 12.19, P = 0.003). Our data demonstrated that lung function declined over time after HSCT and that the decline itself had a significant impact on survival regardless of LONIPC.

Background Recently, thoracoscopic resection of pulmonary sequestration has become more common, since resection of an aberrant artery using an end-stapler is a safe maneuver in many cases. However, injury of the vessels can lead to major hemorrhage. We reported our surgical experience based on thoracoscopic surgery, with five cases of interlobar pulmonary sequestration, focusing on precautions for aberrant arterial vessels. Object and methods We performed pulmonary resections for five patients with interlobar pulmonary sequestration in a lower lobe (left, n = 4; right, n = 1) between April 2004 and May 2020. All aberrant vessels were derived from the lower thoracic artery. Two patients had a single aberrant artery and three had multiple. In four patients, these vessels were detected before surgery, and pulmonary sequestration was diagnosed in four. In one elderly patient, the aberrant vessel was overlooked, and lung cancer was suspected before surgery. Angiography or multidetector-row computed tomography was subsequently performed in four cases. The surgical plan was determined according to the location and size of the pulmonary lesion and three-dimensional images of aberrant vessels. Result In all patients, approaches were made thoracoscopically. Hemorrhage from an anomalous vessel was encountered in one case. Pulmonary resections included two lobectomies and three limited resections. Angioplasty for the root of anomalous branches was performed following pulmonary resections under converted minimal lateral thoracotomy in two cases. Conclusion Preoperative assessment of the anatomical variations in abnormal vessels is essential to achieve safe surgical procedures. According to the situation of the aberrant vessels, selecting surgical procedures with consideration of potential subsequent complications arising over a long period of time is important.

We report on a rare case of thoracoscopic surgery for a patient with an aberrant pulmonary artery of the inferior lobar branch (A7) in the right lower lobe. A 69-year-old woman presented with a chief complaint of an abnormal shadow on chest radiography. Computed tomography (CT) revealed a 14-mm solid nodule in the right lower lobe. The patient was diagnosed with lung cancer by bronchoscopic biopsy, and a surgery was planned. Preoperative thin-slice CT and three-dimensional CT showed an aberrant A7 branching from the right main pulmonary artery. The right lower lobe and lymph node dissection was performed safely under a video view. Preoperative evaluation of this anomaly is important for a safe surgery.