Aberrant proximal tubule DNA methylation underlies phenotypic changes related to kidney dysfunction in patients with diabetes.

Epigenetic mechanisms are considered to contribute to diabetic nephropathy by maintaining memory of poor glycemic control during the early stages of diabetes. However, DNA methylation changes in the human kidney are poorly characterized, because of the lack of cell type-specific analysis. We examined DNA methylation in proximal tubules purified from diabetic nephropathy patients and identified differentially methylated CpG sites, given the critical role of proximal tubules in the kidney injury. Hypermethylation was observed at CpG sites annotated to genes responsible for proximal tubule functions, including gluconeogenesis, nicotinamide adenine dinucleotide synthesis, transporters of glucose, water, phosphate, and drugs, in diabetic kidneys, while genes involved in oxidative stress and the cytoskeleton exhibited demethylation. Methylation levels of CpG sites annotated to ACTN1, BCAR1, MYH9, UBE4B, AFMID, TRAF2, TXNIP, FOXO3, and HNF4A were correlated with the estimated glomerular filtration rate, while methylation of the CpG site in RUNX1 was associated with interstitial fibrosis and tubular atrophy. Hypermethylation of G6PC and HNF4A was accompanied by decreased expression in diabetic kidneys. Proximal tubule-specific hypomethylation of metabolic genes related to HNF4A observed in control kidneys was compromised in diabetic kidneys, suggesting a role for aberrant DNA methylation in the dedifferentiation process. Multiple genes with aberrant DNA methylation in diabetes overlapped genes with altered expressions in maladaptive proximal tubule cells, including transcription factors PPARA and RREB1. In conclusion, DNA methylation derangement in the proximal tubules of patients with diabetes may drive phenotypic changes, characterized by inflammatory and fibrotic features, along with impaired function in metabolism and transport.

4-Hydroxy hexenal derived from dietary n-3 polyunsaturated fatty acids induces anti-oxidative enzyme heme oxygenase-1 in multiple organs.

It has recently been reported that expression of heme oxygenase-1 (HO-1) plays a protective role against many diseases. Furthermore, n-3 polyunsaturated fatty acids (PUFAs) were shown to induce HO-1 expression in several cells in vitro, and in a few cases also in vivo. However, very few reports have demonstrated that n-3 PUFAs induce HO-1 in vivo. In this study, we examined the effect of fish-oil dietary supplementation on the distribution of fatty acids and their peroxidative metabolites and on the expression of HO-1 in multiple tissues (liver, kidney, heart, lung, spleen, intestine, skeletal muscle, white adipose, brown adipose, brain, aorta, and plasma) of C57BL/6 mice. Mice were divided into 4 groups, and fed a control, safflower-oil, and fish-oil diet for 3 weeks. One group was fed a fish-oil diet for just 1 week. The concentration of fatty acids, 4-hydroxy hexenal (4-HHE), and 4-hydroxy nonenal (4-HNE), and the expression of HO-1 mRNA were measured in the same tissues. We found that the concentration of 4-HHE (a product of n-3 PUFAs peroxidation) and expression of HO-1 mRNA were significantly increased after fish-oil treatment in most tissues. In addition, these increases were paralleled by an increase in the level of docosahexaenoic acid (DHA) but not eicosapentaenoic acid (EPA) in each tissue. These results are consistent with our previous results showing that DHA induces HO-1 expression through 4-HHE in vascular endothelial cells. In conclusion, we hypothesize that the HO-1-mediated protective effect of the fish oil diet may be through production of 4-HHE from DHA but not EPA in various tissues.

A case of immunoglobulin G4-related kidney disease manifesting after dipeptidyl peptidase-4 inhibitor treatment.

A 68-year-old man with type 2 diabetes mellitus was admitted with decreased renal function. He had high IgG4 (1070 mg/dL) and hypocomplementemia (CH50, 25 U/mL). Kidney biopsy showed tubulointerstitial nephritis with IgG4-positive plasma cell infiltration. Four years later, a second kidney biopsy revealed a new manifestation of membranous nephropathy and tubulointerstitial nephritis with exacerbated fibrosis formation. Six years later, the patient developed bullous pemphigoid, which was thought to be caused by DPP4 inhibitors, so DPP4 inhibitor treatment was discontinued. The use of DPP4 inhibitors correlated with changes in renal function, and the patient was diagnosed with IgG4-related kidney disease related to DPP4 inhibitors.

De novo posttransplant membranous nephropathy after COVID-19 vaccination 9 years after renal transplantation in a patient with polycystic kidney disease.

A 63-year-old man with polycystic kidney disease underwent kidney transplantation from his wife. Nine years later, after the first and second doses of the COVID-19 vaccination, he developed proteinuria, hematuria, and elevated C-reactive protein. Kidney biopsy 7 months after the initial appearance of proteinuria showed immunoglobulin (Ig)-G granular stain, predominantly IgG1, and spike formation in the glomerular basement membrane. Electron microscopy revealed mainly subepithelial deposits, which corresponds to membranous nephropathy (MN) stage 3 of the Ehrenreich-Churg classification indicating chronic disease, but it also showed electron-dense deposits and endothelial damage. Because a kidney biopsy was performed 1 h after renal transplantation and a biopsy of the patient's native kidney showed intact glomeruli, atypical de novo posttransplant membranous nephropathy (MN) was diagnosed, and a close relationship with COVID-19 vaccination was assumed. Clinicians should consider the involvement of COVID-19 vaccination in de novo posttransplant MN with unclear pathogenesis.

A Bone Histomorphometric Analysis of Hypophosphatasia-related Osteoporosis after Teriparatide Treatment.

A 79-year-old man was admitted with a compression fracture of the first lumbar vertebra. His alkaline phosphatase (ALP) level was 35 IU/L, and his dual energy X-ray absorptiometry T score was -3.7 standard deviations, indicating osteoporosis. A genetic analysis showed a mutation of the alkaline phosphatase biomineralization-associated gene encoding tissue-nonspecific alkaline phosphatase. Hypophosphatasia-related osteoporosis was diagnosed. Alendronate, teriparatide, and minodronate were administered in that order. The ALP level increased during teriparatide use. A bone biopsy performed after three years of teriparatide treatment showed that cancellous bone was adynamic. In cortical bone, tetracycline double-labeling indicates enhanced bone formation. Teriparatide may thus be a viable treatment option even in patients with hypophosphatasia.

Successful peficitinib monotherapy for the new-onset skin manifestations of rheumatoid vasculitis after long-term treatment with tocilizumab for rheumatoid arthritis.

Rheumatoid vasculitis (RV) is a severe extra-articular systemic manifestation of rheumatoid arthritis (RA). Its prevalence has been decreasing for decades because of improved early diagnosis of RA and advances in RA treatment, but it remains a life-threatening disease. The standard treatment for RV has been a glucocorticoid and disease-modifying antirheumatic drugs. Biological agents, including antitumour necrosis factor inhibitors, are also recommended for refractory cases. However, there are no reports of Janus kinase (JAK) inhibitor use in RV. We experienced a case of an 85-year-old woman with a 57-year history of RA who had been treated with tocilizumab for 9 years after receiving three different biological agents over 2 years. Her RA seemed to be in remission in her joints, and her serum C-reactive protein had decreased to 0.0 mg/dL, but she developed multiple cutaneous leg ulcers associated with RV. Because of her advanced age, we changed her RA treatment from tocilizumab to the JAK inhibitor peficitinib in monotherapy, after which the ulcers improved within 6 months. This is the first report to indicate that peficitinib is a potential treatment option for RV that can be used in monotherapy without glucocorticoids or other immunosuppressants.

Crescentic Glomerulonephritis with Fibrinoid Vasculitis after Administration of Influenza Vaccine.

A 66-year-old man was admitted to our hospital because of a low-grade fever and arthralgia. The symptoms started on the third day after influenza vaccine administration and persisted for two months. Serum creatinine was 1.0 mg/dL; C-reactive protein, 16.1 mg/dL; and myeloperoxidase antineutrophil cytoplasmic antibodies (MPO-ANCA), 4,170 IU/mL. A kidney biopsy showed crescentic glomerulonephritis with fibrinoid necrosis of small arteries. Microscopic polyangiitis was diagnosed. After five months of steroid pulse therapy and rituximab administration, the patient entered remission. There have been very few reports of this condition after influenza vaccine administration.

Apolipoprotein E-associated Lipoprotein Glomerulo-tubulopathy.

A 32-year-old man was admitted for the evaluation of proteinuria (5.69 g/day). A light microscopic examination showed markedly dilated glomerular capillary loops with vacuolated areas in many glomeruli, and vacuolated areas were seen on peritubular capillaries in the tubulointerstitium. When electron microscopy specimens prepared by pre-fixation with glutaraldehyde and post-fixation with osmium tetroxide were used for oil red staining, the deposition was confirmed on the affected areas. A genetic analysis of apoE showed that the lipoprotein glomerulopathy was due to apoE-Sendai (Arg145Pro, p.R163P) heterozygosity, which was found in not only the patient but also his mother and twin brother.

Can Takayasu Arteritis Cause Hydronephrosis?

A 74-year-old woman was admitted because of malaise and a low-grade fever. Her C-reactive protein level was 0.96 mg/dL. Computed tomography (CT) revealed diffuse uniform thickening of the arterial wall from the abdominal aorta to the common iliac artery and right hydronephrosis. 18F-fluordesoxyglucose positron emission tomography-CT showed an accumulation in the same area. These findings suggested Takayasu arteritis and retroperitoneal fibrosis as differential diagnoses. Takayasu arteritis is characterized by thickening of the arterial walls, and retroperitoneal fibrosis is characterized by membranous lesions covering the outer surface of the arterial walls. Thus, Takayasu arteritis was deemed the most likely diagnosis. Steroid treatment was effective.

Abnormal subcellular localization of AQP5 and downregulated AQP5 protein in parotid glands of streptozotocin-induced diabetic rats.

BACKGROUND: The mechanisms underlying diabetic xerostomia have not been clarified in relation with aquaporin-5 (AQP5) subcellular localization in salivary glands. METHODS: Western blotting, real-time PCR, and immunocytochemistry were used to analyse AQP5 protein levels and mRNA expression. AQP5 protein levels were measured in the apical plasma membrane (APM) and detergent-insoluble fraction prepared from streptozotocin-diabetic rat parotid glands. RESULTS: Despite an increase in AQP5 mRNA, AQP5 protein levels were decreased in diabetic parotid glands compared with controls. Immunohistochemical studies indicated that AQP5, under unstimulated conditions, colocalised with flotillin-2 and GM1 with a diffuse pattern in the apical cytoplasm of acinar and duct cells in both control and diabetic rats. Ten minutes after intravenous injection of muscarinic agonist cevimeline, AQP5 was dramatically increased together with flotillin-2 and GM1 in the APM of parotid acinar and duct cells of control but not diabetic rats. Sixty minutes after injection, AQP5 was located in a diffuse pattern in the apical cytoplasm in both rats. Treatment of the parotid tissues with cevimeline for 10min increased the Triton X-100 solubility of AQP5 in control but not diabetic rats. Administration of insulin to diabetic rats tended to restore the cevimeline-induced translocation of AQP5. CONCLUSION: Lack of AQP5 translocation in the salivary gland in response to a muscarinic agonist and downregulation of AQP5 protein might lead to diabetic xerostomia. GENERAL SIGNIFICANCE: Cevimeline is useful to cure diabetic xerostomia under insulin administration.

Successful peficitinib addition on anti-MDA5 antibody-positive dermatomyositis refractory to triple therapy and glucocorticoid reduction.

Anti-melanoma differentiation-associated gene 5 antibody-positive dermatomyositis is the poorest prognosis of all dermatomyositis due to its associated rapidly progressive interstitial lung disease. Intensive treatment is required from the onset and triple therapy with prednisolone, calcineurin inhibitors, and intravenous cyclophosphamide is recommended. However, some patients are refractory or dependent on this treatment and additional immunosuppressive therapy is required. Recently, the efficacy of tofacitinib, a JAK inhibitor, has been reported. Here, we describe a case of a 50-year-old woman with anti-melanoma differentiation-associated gene 5 antibody-positive dermatomyositis who became refractory to triple therapy and prednisolone reduction, and achieved remission with the addition of peficitinib, a JAK inhibitor. This is the first report showing that peficitinib is effective for anti-melanoma differentiation-associated gene 5 antibody-positive dermatomyositis and it may be a potential treatment option.

Characterizing the novel protein p33MONOX.

The novel protein p33MONOX (p33Monooxygenase) was over-expressed in neuroblastoma cells demonstrating its inhibitory effect on the phosphorylation of the App (amyloid precursor protein) and Bcl2 (B-cell lymphoma 2) proteins but mediating higher activation of Mapk1/3 (mitogen-activated protein kinase 1/3). We employed a variety of cell biology techniques to show the localization of p33MONOX to the cytoplasm of pyramidal neurons in the mouse brain hippocampus. We also carried out a yeast-two-hybrid screening plus co-immunoprecipitation and bio-informatics to determine COBRA1 (cofactor of BRCA1 (breast cancer type 1)), NOL12 (nucleolar protein 12), and PRNP (prion protein) as p33MONOX-interacting proteins. Bio-computational analyses revealed a flavine-containing monooxygenase (FMO)-1 motif, thus linking p33MONOX to a group of previously characterized proteins, the MICALs (molecule interacting with CasL). Concluding, p33MONOX might regulate pre- and post-transcriptional control of dynamic processes related to growth cone guidance.

Bioanalysis of therapeutic monoclonal antibody by peptide adsorption-controlled LC-MS.

Aim: We aimed to develop an easy, low-cost and versatile mass spectrometric method for the bioanalysis of a therapeutic monoclonal antibody (mAb) in human serum that employs peptide adsorption-controlled (PAC)-LC/MS using selected reaction monitoring mode (LC-MS/MS-SRM). Materials & methods: Rituximab was used as a model mAb. To apply the method to human serum samples, a peptide of the complementarity-determining region was selected as the surrogate peptide. The usefulness of PAC-LC-MS/MS-SRM was evaluated by a collaborative study. Results: The calibration curve ranged from 0.5 (or 1.0) to 1000.0 µg/ml. The selectivity, linearity, accuracy and precision met the predefined acceptance criteria. Conclusion: Our method could be a useful bioanalytical method for the quantification of mAbs in clinical samples.

Neurotrophin-4 (ntf4) mediates neurogenesis in mouse embryonic neural stem cells through the inhibition of the signal transducer and activator of transcription-3 (stat3) and the modulation of the activity of protein kinase B.

The effect of neurotrophin-4 (Ntf4) on mouse embryonic (day-14) neural stem cell (mE14-NSC) fate determination and the mechanisms involved were investigated. Using primary mE14-NSCs, immunocytochemistry and molecular-cell biological methods, such as Western-blotting, we characterized the effect of Ntf4 on mE14-NSC differentiation. Obtained in-vitro data revealed an interesting phenomenon of Ntf4 action resulting in enhanced mE14-NSC commitment to progenitor cells of the neuronal lineage. During this process, Ntf4 suppresses the interleukin 6 (Il6) family receptor and the Notch signalling pathways by modulating their specific receptor cleavages. The observed lineage commitment is controlled via an Ntf4-mediated modulation of protein kinase B (PKB/Akt) activity and characterized by a decreased Stat3 (signal transducer and activator of transcription-3) phosphorylation status. These findings suggest that the Ntf4-activated signalling cascade is responsible for initiating a concert among sheddases, kinases, and phosphatases to mediate neurogenesis.

Generic MS-based method for the bioanalysis of therapeutic monoclonal antibodies in nonclinical studies.

Aim: A generic bioanalytical method was developed to quantify therapeutic IgG1 monoclonal antibodies (mAbs) in mouse sera by combining an easy sample preparation method with LC/MS using selected reaction monitoring. Materials & methods: Rituximab and trastuzumab were used as model mAbs. A synthetic stable isotope-labeled peptide or a stable isotope-labeled mAb was used as an internal standard. The method feasibility was evaluated by a collaborative study involving six laboratories. Results: The calibration curve ranged from 1.0 to 1000.0 µg/ml (correlation coefficient >0.99). The validation parameters including selectivity, linearity of calibration curve, accuracy and precision met the predefined acceptance criteria. Conclusion: Our method is a useful bioanalytical method for the quantification of therapeutic IgG mAbs in nonclinical animal studies.

Report on the breakage of the tip of a radial endobronchial ultrasonic probe sheath during bronchoscopy.

A lesion in a 73-year-old woman that was suspected to be right lung cancer was biopsied under ultrasound-guided bronchoscopy with a guide sheath. The procedure was completed without a noticeable problem, but after 3 days, it was found that the tip of the ultrasonic probe sheath was broken and that the broken fragment was missing. Based on the concern that the fragment had been left in the lung, the patient was examined by computed tomography scan 4 days after the biopsy, and bronchoscopy was repeated 38 days after the biopsy, but no fragment was detected. These procedures and an investigation by the Olympus Corporation led to the conclusion that the fragment was not in the lung, and it was not found in a subsequent surgical specimen. Breakage of devices may occur at any time regardless of progression of fatigue (wear) with increased use, and thorough device management before, during, and after use is important.

Bronchoscopic local steroid spray to prevent bronchial tuberculosis-induced cicatricial bronchial stenosis: A case series.

RATONALE: Cicatricial bronchial stenosis or obstruction occurring in the healing process of endobronchial tuberculosis (ET) is a problematic complication of tuberculous airway lesions. Prevention by internal medical treatment is desired. PATIENT CONCERNS: This case series describes four patients who diagnosed ET with Type IIIb (protruding ulcer-type) based on Arai's classification of bronchoscopic findings of bronchial tuberculosis. DIAGNOSES: Endobronchial tuberculosis. INTERVENTIONS: A local steroid spray was applied bronchoscopically to active protruding ulcer-type lesions (which are likely to cause cicatricial stenosis) that extended in the transverse direction and occupied one-half or more of the circumference on bronchoscopy. OUTCOMES: Cicatricial stenosis was prevented in two of four patients. Treatment was discontinued in athird patient because tolerance could not be achieved, although the patient's condition had improved. In the fourth patient, treatment was switched to systemic steroid administration because of a problem with tolerance and the broad range of the lesion; however, stenosis remained. LESSONS: Local steroid spray-applied bronchoscopically to bronchial tuberculosis lesions in the ulcer formation and granulation periods may help prevent stenosis.

Transbronchial drainage using endobronchial ultrasonography with guide sheath for lung abscess: A case report.

RATIONALE: Lung abscess was previously treated surgically, but is now mainly treated with antibiotics and ideally with direct drainage, although postural drainage canalso be used. PATIENT CONCERNS: A chest abnormal shadow was detected in an 82-year-old man and he was referred to our department in November 2017. On chest computed tomography (CT), a low-density mass shadow was present in the left S8 segment. Lung abscess and lung cancer were considered as differential diagnoses, and treatment with sulbactam sodium/ampicillin sodium (SBT/ABPC) was first initiated for lung abscess. The etiologic agent could not be identified by sputum examination, and the abscess shadow remained. DIAGNOSES: Lung abscess. INTERVENTIONS: Endobronchial ultrasonography with a guide sheath (EBUS-GS)-guided bronchoscopy was performed on hospital day 21 to diagnose the lesion, identify the etiologic agent if the lesion was a lung abscess, and attempt drainage. Vacuum aspiration performed in the guide sheath after the probe was placed within the lesion produced 4-5 ml of gray turbid pus, and the abscess was judged to have been drained. OUTCOMES: A subsequent pathological examination did not detect malignant cells. Klebsiella pneumoniae, Prevotella spp. was identified as the etiologic agent in bacteriological tests. Antibiotics were changed based on sensitivity test results, and drainage was similarly performed on hospital day 28. The shadow gradually improved and disappeared. Therefore, this procedure and treatment led to identification of the etiologic agent and helped with cure of the disease. LESSONS: Based on the basic principle of treatment for abscess using as much drainage as possible, EBUS-GS-guided transbronchial drainage may be considered to be a "new procedure" for lung abscess.

Sudden Death from Cardiopulmonary Arrest on Arrival of a Patient with Pulmonary Tuberculosis: A Case Diagnosed by Postmortem CT and Autopsy.

Sudden death due to massive hemoptysis during management of tuberculosis occurs in a considerable number of patients. However, when massive airway hemorrhage occurs in a patient in whom tuberculosis has not been confirmed and a blood is not apparent externally on the face/body, it is difficult to immediately identify the cause of death as airway obstruction by tuberculous bleeding in the airway. We encountered an 83-year-old Japanese woman with her medical history included treatment of tuberculosis in her 20s who was in cardiopulmonary arrest on arrival (CPAOA), and the cause of sudden death could not initially be identified. Postmortem CT (PMCT) and autopsy revealed that the cause of sudden death was airway obstruction/asphyxia by tuberculous massive airway hemorrhage. Identification of the cause of death facilitated a subsequent active contact investigation and led to prevention of secondary tuberculosis infection.

Tuberculous pleurisy mimicking Mycoplasma pneumoniae infection in a previously healthy young adult: A case report.

RATONALE: Sometimes, pleural effusion accompanying an acute Mycoplasma pneumoniae infection or tuberculous pleurisy has similar analysis results. We report a case of tuberculous pleurisy which was initially diagnosed as acute M pneumoniae infection, which is of special interest because anti-Mycoplasma antibody results were positive, which served as a red herring. PATIENT CONCERNS: A 20-year-old woman visited the outpatient emergency romm of our hospital for chief complaints of high fever, dry cough, and pleuralgia persiting for 2 days. Since anti-mycoplasma antibody test results were positive, we treated acute M pneumoniae infection and drained her pleural effusion. The condition tended to improve, but on day 16 postadmission, the acid-fast bacterial culture of the pleural effusion was positive for Mycobacterium tuberculosis. DIAGNOSES: Tuberculous pleurisy. INTERVENTIONS: After the diagnosis, the patient received antituberculous drugs. OUTCOMES: She completed treatment with no noticeable adverse events, and the right pleural effusion disappered and diffuse right pleural thickening improved. LESSONS: Exudative pleural effusion with lymphocyte dominance and a high adenosine deaminase level in M pneumoniae infection have been reported. Even though the condition suggests acute M pneumoniae infection, clinicians should be aware that tuberculous pleurisy and M pneumoniae infection can share similar clinical features, and should understand the usefulness and limitations of the anit-Mycoplasma antibody test.