Toward Fully Controllable Monomers Sequence: Binary Organocatalyzed Polymerization from Epoxide/Aziridine/Cyclic Anhydride Monomer Mixture.

The sequence of monomers within a polymer chain plays a pivotal role in determining the physicochemical properties of the polymer. In the copolymerization of two or more monomers, the arrangement of monomers within the resulting polymer is primarily dictated by the intrinsic reactivity of the monomers. Precisely controlling the monomer sequence in copolymerization, particularly through the manipulation of catalysts, is a subject of intense interest and poses significant challenges. In this study, we report the catalyst-controlled copolymerization of epoxides, N-tosyl aziridine (TAz), and cyclic anhydrides. To achieve this, a binary catalyst system comprising a Lewis acid, triethylborane, and Brønsted base, t-BuP1, was utilized. This system was utilized to regulate the selectivity between two catalytic reactions: ring-opening alternating copolymerization (ROAC) of epoxides/cyclic anhydrides and ROAC of TAz/cyclic anhydrides. Changing the catalyst ratio made it possible to continuously modulate the resulting poly(ester-amide ester) from ABA-type real block copolymers to gradient, random-like, reversed gradient, and reversed BAB-type block-like copolymers. A range of epoxides and anhydrides was investigated, demonstrating the versatility of this polymerization system. Additionally, density functional theory calculations were conducted to enhance our mechanistic understanding of the process. This synthetic method not only provides a versatile means for producing copolymers with comparable chemical compositions but also facilitates the exploration of the intricate relationship between monomer sequences and the resultant polymer properties, offering valuable insights for advancements in polymer science.

Genotype and X-chromosome inactivation are associated with disease severity in females with X-linked Alport syndrome.

BACKGROUND AND HYPOTHESIS: Male patients with X-linked Alport syndrome (XLAS) generally develop end-stage kidney disease in early or middle adulthood and show distinct genotype-phenotype correlations. Female patients, however, show various phenotypes ranging from asymptomatic to severe with no genotype-phenotype correlations. However, the factors affecting the severity of XLAS in female patients are unclear. Since X-chromosome inactivation (XCI) affects the severity of certain female X-linked diseases, we investigated whether genotype and XCI were associated with XLAS severity in female patients in a large Japanese cohort. METHODS: Among 139 female patients with genetically diagnosed XLAS at our institution, we conducted XCI analysis on peripheral blood leukocytes using the human androgen receptor assay method and analyzed two cohorts. In 74 adult female patients, we evaluated the correlation between kidney function (creatinine-estimated glomerular filtration rate [Cr-eGFR] optimized for Japanese individuals) and genotype/XCI using multivariable linear regression analysis, and in 65 pediatric female patients, we evaluated the correlation between kidney function (Cr-eGFR optimized for Japanese individuals) and genotype/XCI using multivariable linear regression analysis. We also investigated the correlation between the development of proteinuria (urine protein-to-creatinine ratio above normal for the patient's age) and genotype/XCI using multivariable Cox proportional hazard analysis. RESULTS: In adult female patients, XCI pattern was significantly associated with Cr-eGFR (regression coefficient estimate = -0.53, P = 0.004), whereas genotype was not (P = 0.892). In pediatric female patients, both genotype and XCI pattern were significant independent risk factors for the development of proteinuria (hazard ratio [HR], 3.702; 95% confidence interval [CI], 1.681-8.150; P = 0.001 and HR, 1.043; 95% CI, 1.061-1.070; P = 0.001, respectively), whereas both genotype and XCI pattern were not associated with Cr-eGFR (P = 0.20, P = 0.67, respectively). CONCLUSION: Genotype and XCI are factors associated with the severity in females with XLAS.

Evaluation of pathogenicity of WT1 intron variants by in vitro splicing analysis.

BACKGROUND: Wilms tumor 1 (WT1; NM_024426) causes Denys-Drash syndrome, Frasier syndrome, or isolated focal segmental glomerulosclerosis. Several WT1 intron variants are pathogenic; however, the pathogenicity of some variants remains undefined. Whether a candidate variant detected in a patient is pathogenic is very important for determining the therapeutic options for the patient. METHODS: In this study, we evaluated the pathogenicity of WT1 gene intron variants with undetermined pathogenicity by comparing their splicing patterns with those of the wild-type using an in vitro splicing assay using minigenes. The three variants registered as likely disease-causing genes: Mut1 (c.1017-9 T > C(IVS5)), Mut2 (c.1355-28C > T(IVS8)), Mut3 (c.1447 + 1G > C(IVS9)), were included as subjects along the 34 splicing variants registered in the Human Gene Mutation Database (HGMD)®. RESULTS: The results showed no significant differences in splicing patterns between Mut1 or Mut2 and the wild-type; however, significant differences were observed in Mut3. CONCLUSION: We concluded that Mut1 and Mut2 do not possess pathogenicity although they were registered as likely pathogenic, whereas Mut3 exhibits pathogenicity. Our results suggest that the pathogenicity of intronic variants detected in patients should be carefully evaluated.

The impact of carbapenem shortage and stewardship countermeasures on antimicrobial practice at a tertiary care center.

We evaluated the impact of carbapenem shortage on antimicrobial practice and patient outcome at a tertiary care center. During the shortage, hospital antimicrobial practice could be safely managed through additional antimicrobial stewardship measures including treatment guidance and mandatory preauthorization. Antimicrobial shortage may present a unique opportunity for promoting antimicrobial stewardship.

Systematic Review of Clinical Characteristics and Genotype-Phenotype Correlation in LAMB2-Associated Disease.

Introduction: Laminin subunit beta-2 (LAMB2)-associated disease, termed Pierson syndrome, presents with congenital nephrotic syndrome, ocular symptoms, and neuromuscular symptoms. In recent years, however, the widespread use of next-generation sequencing (NGS) has helped to discover a variety of phenotypes associated with this disease. Therefore, we conducted this systematic review. Methods: A literature search of patients with LAMB2 variants was conducted, and 110 patients were investigated, including 12 of our patients. For genotype-phenotype correlation analyses, the extracted data were investigated for pathogenic variant types, the severity of nephropathy, and extrarenal symptoms. Survival analyses were also performed for the onset age of end-stage kidney disease (ESKD). Results: Among all patients, 81 (78%) presented with congenital nephrotic syndrome, and 52 (55%) developed ESKD within 12 months. The median age at ESKD onset was 6.0 months. Kidney survival analysis showed that patients with biallelic truncating variants had a significantly earlier progression to ESKD than those with other variants (median age 1.2 months vs. 60.0 months, P < 0.05). Although the laminin N-terminal domain is functionally important in laminin proteins, and variants in the laminin N-terminal domain are said to result in a severe kidney phenotype such as earlier onset age and worse prognosis, there were no significant differences in onset age of nephropathy and progression to ESKD between patients with nontruncating variants located in the laminin N-terminal domain and those with variants located outside this domain. Conclusion: This study revealed a diversity of LAMB2-associated diseases, characteristics of LAMB2 nephropathy, and genotype-phenotype correlations.

Similarities in rotavirus vaccine viral shedding and immune responses in pairs of twins.

Objectives: Intestinal rotavirus (RV) vaccine replication and host immune response are suggested to be affected by several factors, including maternal antibodies, breastfeeding history, and gut microbiome, which are thought to be similar in pairs of twins. The aim of this study was to determine whether viral shedding from the fecal RV vaccine strain Rotarix® (RV1) and IgG and IgA responses to RV show similarity in pairs of twins. Methods: Quantitative reverse transcription polymerase chain reaction specific to RV vaccine strain RV1 was used to monitor fecal RV1 viral shedding. RV IgG and IgA titers were measured using an in-house enzyme-linked immunosorbent assay. Fecal RV1 viral shedding and immune responses were compared between twins and singletons with mixed effects and fixed effects models. Results: A total of 347 stool and 54 blood samples were collected from four pairs of twins and twelve singletons during the observation period. Although the kinetics of fecal RV1 viral shedding and immune responses differed among vaccinated individuals, they appeared to be similar within twin pairs. RV shedding after the first dose (P=0.049) and RV IgG titers during the entire observation period (P=0.015) had a significantly better fit in the fixed effect model that assumed that twins have the same response versus the model that assumed that twins have a different response. Conclusions: The similarity of RV vaccine viral replication in intestine and host immune responses in twin pairs was demonstrated using statistical analysis.

High whole-body bone mineral density in ossification of the posterior longitudinal ligament.

BACKGROUND CONTEXT: Recent studies suggest that ossification of the posterior longitudinal ligament (OPLL) is exacerbated by systemic metabolic disturbances, including obesity. However, although an increase in bone mineral density (BMD) measured at the lumbar spine has been reported in patients with OPLL, no studies have investigated the systemic BMD of patients with OPLL in detail. PURPOSE: We investigated whether patients with OPLL develop increased whole-body BMD. STUDY DESIGN: Single institution cross-sectional study. PATIENT SAMPLE: Data were collected from Japanese patients with symptomatic OPLL (OPLL [+]; n=99). Control data (OPLL [-]; n=226) without spinal ligament ossification were collected from patients who underwent spinal decompression, spinal fusion, or hip replacement surgery. OUTCOME MEASURES: Demographic data, including age, body mass index (BMI), comorbidities, history of treatment for osteoporosis, and history of vertebral and nonvertebral fractures, was obtained from all participants. In addition, whole-body BMD, including the lumbar spine, thoracic spine, femoral neck, skull, ribs, entire upper extremity, entire lower extremity, and pelvis, were measured in all participants using whole-body dual-energy X-ray absorptiometry. METHODS: Patient data were collected from 2018 to 2022. All participants were categorized based on sex, age (middle-aged [<70 years] and older adults [≥70 years]), and OPLL type (localized OPLL [OPLL only in the cervical spine], diffuse OPLL [OPLL in regions including the thoracic spine]), and OPLL [-]) and each parameter was compared. The factors associated with whole-body BMD were evaluated via multivariable linear regression analysis. RESULTS: Compared with the OPLL (-) group, the OPLL (+) group of older women had significantly higher BMD in all body parts (p<.01), and the OPLL (+) group of older men had significantly higher BMD in all body parts except the ribs, forearm, and skull (p<.01). The factors associated with increased BMD of both the femoral neck (load-bearing bone) and skull (nonload-bearing bone) were age, BMI, and coexisting diffuse OPLL in women and BMI and coexisting localized OPLL in men. CONCLUSIONS: Patients with OPLL have increased whole-body BMD regardless of sex, indicating that it is not simply due to load-bearing from obesity. These findings suggested that OPLL is associated with a systemic pathology.

Association of Familial Fanconi Syndrome with a Novel GATM Variant.

Fanconi syndrome is a disorder of the proximal renal tubule. Recently, advanced genetic analysis technology has revealed that several genes cause familial Fanconi syndrome. We identified a family with autosomal dominant Fanconi syndrome and chronic kidney disease with a novel glycine amidinotransferase (GATM) variant. Case 1 was a 57-year-old Japanese woman. Her father and two siblings had Fanconi syndrome or chronic kidney disease. She presented to our hospital at the age of 34 years with recurrent glucosuria. Her height and weight were 151 cm and 46.6 kg, respectively. Laboratory tests showed glucosuria, hypophosphatemia, hypouricemia, and normal renal function. Her serum creatinine level gradually increased over the following next two decades, and she developed end-stage renal disease. Case 2, the daughter of Case 1, was a 26-year-old woman. Her height and weight were 151 cm and 37.5 kg, respectively. Glucosuria was detected at the age of 13 years, which led to a referral to our hospital. Urinalysis showed low-molecular-weight proteinuria. She was diagnosed with Fanconi syndrome. At the age of 26 years, she had glucosuria, low-molecular-weight proteinuria, hypouricemia, and normal renal function. Genetic testing of both cases revealed a novel missense variant in GATM. The heterozygous missense variants in GATM have been reported to cause familial Fanconi syndrome, which manifests early in life and progresses to renal glomerular failure by mid-adulthood. The novel GATM variant detected in our cases was suspected to be associated with the development of Fanconi syndrome. GATM variants should be tested in patients with idiopathic Fanconi syndrome.

All reported non-canonical splice site variants in GLA cause aberrant splicing.

BACKGROUND: Fabry disease is an X-linked lysosomal storage disorder caused by insufficient α-galactosidase A (GLA) activity resulting from variants in the GLA gene, which leads to glycosphingolipid accumulation and life-threatening, multi-organ complications. Approximately 50 variants have been reported that cause splicing abnormalities in GLA. Most were found within canonical splice sites, which are highly conserved GT and AG splice acceptor and donor dinucleotides, whereas one-third were located outside canonical splice sites, making it difficult to interpret their pathogenicity. In this study, we aimed to investigate the genetic pathogenicity of variants located in non-canonical splice sites within the GLA gene. METHODS: 13 variants, including four deep intronic variants, were selected from the Human Gene Variant Database Professional. We performed an in vitro splicing assay to identify splicing abnormalities in the variants. RESULTS: All candidate non-canonical splice site variants in GLA caused aberrant splicing. Additionally, all but one variant was protein-truncating. The four deep intronic variants generated abnormal transcripts, including a cryptic exon, as well as normal transcripts, with the proportion of each differing in a cell-specific manner. CONCLUSIONS: Validation of splicing effects using an in vitro splicing assay is useful for confirming pathogenicity and determining associations with clinical phenotypes.

Dyslipidemia as a novel risk for the development of symptomatic ossification of the posterior longitudinal ligament.

BACKGROUND CONTEXT: Obesity and visceral fat have been implicated as potential factors in the pathogenesis of the ossification of the posterior longitudinal ligament (OPLL); the details of the factors involved in OPLL remain unclear. PURPOSE: We aimed to determine the association between dyslipidemia and symptomatic OPLL. STUDY DESIGN: Single institution cross-sectional study. PATIENT SAMPLE: Data were collected from Japanese patients with OPLL (n=92) who underwent whole-spine computed tomography scanning. Control data (n=246) without any spinal ligament ossification were collected from 627 Japanese participants who underwent physical examination. OUTCOME MEASURES: Baseline information and lipid parameters, including triglycerides (TG), high-density lipoprotein cholesterol (HDL-C), and low-density lipoprotein cholesterol (LDL-C) from fasting blood samples were collected to assess the comorbidity of dyslipidemia. METHODS: Patient data were collected from 2020 to 2022. Patients with dyslipidemia were defined as those who were taking medication for dyslipidemia and who met one of the following criteria: TG ≥150 mg/dL, LDL-C ≥140 mg/dL, and/or HDL-C <40 mg/dL. The factors associated with OPLL development were evaluated using multivariate logistic regression analysis. RESULTS: The comorbidity of dyslipidemia in the OPLL group was more than twice that in the control group (71.7% and 35.4%, respectively). The mean body mass index (BMI) of the OPLL group was significantly higher than that of the control group (27.2 kg/m2 and 23.0 kg/m2). Multivariate logistic regression analysis revealed that dyslipidemia was associated with the development of OPLL (regression coefficient, 0.80; 95% confidence interval, 0.11-1.50). Additional risk factors included age, BMI, and diabetes mellitus. CONCLUSIONS: We demonstrated a novel association between dyslipidemia and symptomatic OPLL development using serum data. This suggests that visceral fat obesity or abnormal lipid metabolism are associated with the mechanisms of onset and exacerbation of OPLL as well as focal mechanical irritation due to being overweight.

Effects of Preserving Anatomically Positioned and Adequate Remnant ACL Tissue in Double-Bundle ACL Reconstruction.

Background: The advantages of remnant tissue preservation in anterior cruciate ligament (ACL) reconstruction (ACLR) remain controversial. Hypothesis: It was hypothesized that a large amount of remnant tissue, especially if anatomically positioned, would improve patient-reported outcomes and second-look graft appearance after preserved double-bundle ACLR (DB-ACLR). Study Design: Cohort study; Level of evidence, 3. Methods: This retrospective study included 89 consecutive patients who underwent unilateral remnant-preserving DB-ACLR using 2 hamstring tendon autografts. The authors categorized the arthroscopic findings into 3 groups according to the location and volume of the ACL remnant tissue in the femoral notch: (1) anatomical attachment (group AA; n = 34); (2) nonanatomical attachment (group NA; n = 33); and (3) no remnant (group NR; n = 22). Based on second-look arthroscopy, the reconstructed graft was graded as excellent, fair, or poor. Patient-reported outcomes were evaluated at 2 years after surgery using the Knee injury and Osteoarthritis Outcome Score (KOOS) and the Japanese Anterior Cruciate Ligament Questionnaire-25 (JACL-25). Results: The AA and NA groups had a significantly shorter time from injury to surgery compared with the NR group (P = .0165). Considering the second-look arthroscopic findings, the authors found a significant difference in synovial coverage of the grafts between the 3 groups (P = .0018). There were no significant differences in the overall KOOS and JACL-25 score among the 3 groups; however, the KOOS-Sport and Recreation and KOOS-Quality of Life subscale scores were significantly higher in the AA group compared with the NA and NR groups (P = .0014 and .0039, respectively). The JACL-25 score for middle- to high-speed flexion and extension was significantly better in the AA group versus the NR group (P = .0261). Conclusion: This study showed that preserving anatomically positioned and adequate remnant tissue during DB-ACLR improved second-look graft appearance and KOOS-Sport and Recreation and KOOS-Quality of Life scores.

Changes in bone turnover markers after discontinuing long-term glucocorticoid administration in children with idiopathic nephrotic syndrome: a multicenter retrospective observational study.

BACKGROUND: Glucocorticoids affect bone turnover. Little is known about how bone turnover changes when glucocorticoids are discontinued following long-term administration. METHODS: This retrospective observational study was conducted on the relationship between discontinuation of long-term administration of glucocorticoid and bone turnover markers (BTMs) in patients with childhood-onset idiopathic nephrotic syndrome. Serum bone alkaline phosphatase (BAP), intact procollagen type 1 N-terminal propeptide (P1NP), and tartrate-resistant acid phosphatase-5b (TRACP-5b) were evaluated as BTMs. RESULTS: Thirty-eight pairs of BTMs at glucocorticoid administration and after discontinuation were analyzed in 29 patients. The median age at baseline was 12.4 (interquartile range, 9.0-14.5) years, and the median time from the onset of nephrotic syndrome was 5.9 (3.3-9.7) years. The mean period from prednisolone discontinuation to the measurement of BTMs after glucocorticoid discontinuation was 3.5 ± 1.0 months. Changes in BTMs after glucocorticoid discontinuation were modest when the daily prednisolone dose was < 0.25 mg/kg/day (ln BAP standard deviation [SD] score, p = 0.19; log intact P1NP SD score, p = 0.70; TRACP-5b, p = 0.95). When the daily prednisolone dose was ≥ 0.25 mg/kg/day, all BTMs increased significantly after glucocorticoid discontinuation (ln BAP SD score, p < 0.01; log intact P1NP SD score, p < 0.01; TRACP-5b, p < 0.01). CONCLUSIONS: Decreased BTMs can rise within a few months of discontinuing long-term glucocorticoid administration. When the administered glucocorticoid dose is low, changes in BTMs may be small. A higher resolution version of the Graphical abstract is available as Supplementary information.

Specific Mutations near the Amyloid Precursor Protein Cleavage Site Increase γ-Secretase Sensitivity and Modulate Amyloid-ß Production.

Amyloid-ß peptides (Aßs) are produced via cleavage of the transmembrane region of the amyloid precursor protein (APP) by γ-secretase and are responsible for Alzheimer's disease. Familial Alzheimer's disease (FAD) is associated with APP mutations that disrupt the cleavage reaction and increase the production of neurotoxic Aßs, i.e., Aß42 and Aß43. Study of the mutations that activate and restore the cleavage of FAD mutants is necessary to understand the mechanism of Aß production. In this study, using a yeast reconstruction system, we revealed that one of the APP FAD mutations, T714I, severely reduced the cleavage, and identified secondary APP mutations that restored the cleavage of APP T714I. Some mutants were able to modulate Aß production by changing the proportions of Aß species when introduced into mammalian cells. Secondary mutations include proline and aspartate residues; proline mutations are thought to act through helical structural destabilization, while aspartate mutations are thought to promote interactions in the substrate binding pocket. Our results elucidate the APP cleavage mechanism and could facilitate drug discovery.

Kinetic aspects of iron(III)-chelation therapy with deferasirox (DFX) revealed by the solvolytic dissociation rate of the Fe(III)-DFX complex estimated with capillary electrophoretic reactor.

Capillary electrophoresis was used to estimate the solvolytic dissociation rate (kd) of metal complexes of deferasirox (DFX, H3L), a drug used to treat iron overload. Inert CoIIIL23- did not dissociate. The estimated kd value for FeIIIL23- was (2.7 ± 0.3) × 10-4 s-1 (298 K, pH 7.4). The kd values of other complexes (AlIIIL23-, NiIIL24-, and MnIIL-) were in the range 10-3-10-4 s-1. In contrast, ZnIIL- and CuIIL- were too labile to allow kd estimation. The fact that the half-life of FeIIIL23- (43.3 min) is shorter than the blood half-life of DFX (8-16 h) implies that the blood concentration of DFX should be high enough to prevent dissociation of FeIIIL23-. The possibility of a safer iron-chelation therapy that avoids excretion of other essential metal ions such as ZnII is discussed, highlighting the importance of selectivity in terms of kinetic stability.

Lumbar ossification of the ligamentum flavum reflects a strong ossification tendency of the entire spinal ligament.

Patients with ossification of the ligamentum flavum (OLF) in the lumbar spine may be at high risk of developing concomitant ossification of the entire spinal ligament, but the etiology remains unclear. We investigated the propensity for spinal ligament ossification in asymptomatic subjects with lumbar OLF using the data of 595 Japanese individuals receiving medical check-ups, including computed tomography (CT) scanning. The severity of OLF (total number of intervertebral segments with OLF) of the entire spine on CT was quantified using an OLF index. Subjects with OLF were grouped according to this index: localized OLF (n = 138), intermediate OLF (n = 70), and extensive OLF (n = 31). The proportion of subjects with lumbar OLF increased with increasing OLF index (localized 13.7%, intermediate 41.4%, and extensive 70.9%). Multiple regression analysis found that lumbar OLF index was associated with thoracic OLF index, and co-existence of ossification of the posterior longitudinal ligament (OPLL) of the thoracic and lumbar spine. This study showed that subjects with more multilevel lumbar OLF were more likely to develop multilevel thoracic OLF and to have coexisting OPLL. Patients with lumbar OLF may be a distinctive subgroup with a strong tendency to ossification of the entire spinal ligament.

Aggravation of Ossified Ligamentum Flavum Lesion Is Associated With the Degree of Obesity.

STUDY DESIGN: Retrospective cross-sectional study. OBJECTIVES: There is insufficient data on the clinical features of ossification of the ligamentum flavum (OLF) of the thoracic spine and the risk of progression of ossified lesions. The link between obesity and ossification of the posterior longitudinal ligament (OPLL), which frequently coexists with OLF, has been demonstrated. However, the link between obesity and OLF has not been recognized. We aimed to determine the prevalence of obesity in thoracic OLF and whether the severity of OLF is associated with the degree of obesity. METHODS: A total of 204 symptomatic Japanese subjects with thoracic OLF and 136 subjects without spinal ligament ossification as controls were included. OLF subjects were divided into 3 groups: 1) localized OLF (OLF <2-intervertebral regions); 2) multilevel OLF (OLF ≥3-intervertebral regions); and 3) OLF + OPLL. The severity of OLF was quantified using the OLF index using computed tomography imaging of the entire spine. RESULTS: The proportion of severely obese subjects (BMI ≥ 30 kg/m2) was significantly higher both in the multilevel OLF group (25.5%) and the OLF + OPLL group (44.3%) than in the localized OLF group (3.6%) and the control group (1.4%) (P < 0.01). BMI, age, and coexistence of cervical OPLL and lumbar OLF were associated with thoracic OLF index in the multiple regression analysis. CONCLUSIONS: Our findings demonstrated that obesity is a distinct feature of multilevel OLF in the thoracic spine and that the severity of OLF is associated with the degree of obesity.

Aberrant splicing caused by exonic single nucleotide variants positioned 2nd or 3rd to the last nucleotide in the COL4A5 gene.

BACKGROUND AND OBJECTIVES: The evident genotype-phenotype correlation shown by the X-linked Alport syndrome warrants the assessment of the impact of identified gene variants on aberrant splicing. We previously reported that single nucleotide variants (SNVs) in the last nucleotide of exons in COL4A5 cause aberrant splicing. It is known that the nucleotides located 2nd and 3rd to the last nucleotides of exons can also play an essential role in the first step of the splicing process. In this study, we aimed to investigate whether SNVs positioned 2nd or 3rd to the last nucleotide of exons in COL4A5 resulted in aberrant splicing. METHODS: We selected eight candidate variants: six from the Human Gene Variant Database Professional and two from our cohort. We performed an in-vitro splicing assay and reverse transcription-polymerase chain reaction (RT-PCR) for messenger RNA obtained from patients, if available. RESULTS: The candidate variants were initially classified into the following groups: three nonsense, two missense, and three synonymous variants. Splicing assays and RT-PCR for messenger RNA revealed that six of the eight variants caused aberrant splicing. Four variants, initially classified as non-truncating variants, were found to be truncating ones, which usually show relatively more severe phenotypes. CONCLUSION: We revealed that exonic SNVs positioned 2nd or 3rd to the last nucleotide of exons in the COL4A5 were responsible for aberrant splicing. The results of our study suggest that attention should be paid when interpreting the pathogenicity of exonic SNVs near the 5' splice site.

Strong relationship between dyslipidemia and the ectopic ossification of the spinal ligaments.

Obesity and metabolic disturbances are prevalent in ossification of the posterior longitudinal ligament (OPLL) and ossification of the ligamentum flavum (OLF); however, the involvement of dyslipidemia (DL) in OPLL/OLF remains uncertain. We investigated the association between dyslipidemia and OPLL/OLF using a dataset of 458 individuals receiving health screening tests, including computed tomography. Subjects were grouped according to the presence or location of OPLL/OLF: controls (no OPLL/OLF, n = 230), OLF (n = 167), cervical OPLL (n = 28), and thoracic OPLL (n = 33). They were also grouped according to the presence of dyslipidemia (DL[+], n = 215; DL[-], n = 243). The proportion of dyslipidemia in the OLF and OPLL groups was 1.6-2.2 times higher than that in the control group. The proportion of OLF and OPLL in the DL(+) group was significantly higher than that in the DL(-) group (OLF, 43% vs. 29%; cervical OPLL, 14.4% vs. 3.2%; thoracic OPLL, 11.1% vs. 3.7%). Multivariate logistic regression analysis showed an association between all ossification types and dyslipidemia. This study demonstrated an association of dyslipidemia with OPLL/OLF; further investigation on the causal relationship between dyslipidemia and ectopic spinal ligament ossification is warranted to develop a therapeutic intervention for OPLL/OLF.

CD44 as a pathological marker for the early detection of calcineurin inhibitor-induced nephrotoxicity post kidney transplantation.

Long-term calcineurin inhibitor (CNI) administration causes irreversible nephrotoxicity. Therefore, early CNI-induced nephrotoxicity detection is necessary for patients who will need long-term CNI administration. There is no pathological indicator for early CNI-induced nephrotoxicity. Here, serial protocol kidney biopsy specimens from five kidney-transplant patients with severe CNI-induced nephrotoxicity were examined. We observed that the increase in CD44 expression in glomerular parietal epithelial cells (PECs) preceded the chronic pathological changes of CNI-induced nephrotoxicity such as tubular atrophy/interstitial fibrosis, arterial hyaline thickening, and focal segmental glomerulosclerosis (FSGS). This result suggests that CD44-positive PECs have pivotal roles in FSGS development in human CNI-induced nephrotoxicity as well as rodent models. CD44 could be useful as a pathological marker for early CNI-induced nephrotoxicity detection post kidney transplantation.

Multidimensional Control of Repeating Unit/Sequence/Topology for One-Step Synthesis of Block Polymers from Monomer Mixtures.

Synchronously and thoroughly adjusting the chemical structure difference between two blocks of the diblock copolymer is very useful for designing materials but difficult to achieve via self-switchable alternating copolymerization. Here, we report self-switchable alternating copolymerization from a mixture of two different cyclic anhydrides, epoxides, and oxetanes, where a simple alkali metal carboxylate catalyst switches between ring-opening alternating copolymerization (ROCOP) of cyclic anhydrides/epoxides and ROCOP of cyclic anhydrides/oxetanes, resulting in the formation of a perfect block tetrapolymer. By investigating the reactivity ratio of these comonomers, a reactivity gradient was established, enabling the precise synthesis of block copolymers with synchronous adjustment of each unit's chemical structure/sequence/topology. Consequently, a diblock tetrapolymer with two glass transition temperatures (Tg) can be easily produced by adjusting the difference in chemical structures between the two blocks.