A case of Castleman's disease complicated with nephrotic syndrome due to glomerulopathy mimicking membranoproliferative glomerulonephritis

Castleman's disease is a rare atypical lymphoproliferative disorder. Renal manifestations, such as proteinuria, hematuria, and renal dysfunction, are common in Castleman's disease; however, a nephrotic syndrome rarely occurs. We have encountered an unusual case of Castleman's disease of the plasma cell type characterized by nephrotic syndrome because of glomerulopathy mimicking membranoproliferative glomerulonephritis. Our patient showed higher levels of circulating cytokines (interleukin-6/vascular endothelial cell-derived growth factor), the glomerular lesions not associated with immunocomplex deposition, and the resolution of nephrotic syndrome after successful corticosteroids therapy resulting in a decline in cytokines levels, thereby implicating a cytokine-induced glomerular cell injury/activation as a possible cause of the glomerular pathological changes in this case.     

Accumulation of cholera toxin and GM1 ganglioside in the early endosome of Niemann–Pick C1-deficient cells

We investigated intracellular trafficking of GM1 ganglioside in Niemann-Pick C1 (NPC1)-deficient Chinese hamster ovary cells [NPC1(-) cells] by using cholera toxin (CT) as a probe. Both the holotoxin and the B subunit (CTB) accumulated in GM1-enriched intracellular vesicles of NPC1(-) cells. CTB-labeled vesicles contained the early endosome marker Rab5 but not lysosome-associated membrane protein 2 and were not labeled with either Texas red-transferrin or Lysotracker, indicating that they represent early endosomes. Similarly, CT accumulated in intracellular vesicles of human NPC fibroblasts that contained both Rab5 and early endosomal antigen 1. CTB accumulation in NPC1(-) cells was abolished by expression of wild-type NPC1 but not by mutant proteins with a mutation either in the NPC domain or the sterol-sensing domain. A part of these mutant NPC1 proteins expressed in NPC1(-) cells was localized on CTB-labeled vesicles. U18666A treatment of "knock in" cells [NPC1(-) cells that stably expressed wild-type NPC1] caused CTB accumulation similar to that in NPC1(-) cells, and a part of wild-type NPC1was localized on CTB-labeled vesicles in drug-treated cells. Finally, CT tracer experiments in NPC1(-) cells revealed retarded excretion of internalized toxin into the culture medium and an increase in the intracellular release of A subunits. In accordance with the latter result, CT was more effective in stimulating cAMP formation in NPC1(-) than in wild-type cells. These results suggest that transport of CT/GM1 complexes from the early endosome to the plasma membrane depends on the function of NPC1, whereas transport to the Golgi apparatus/endoplasmic reticulum does not.     

Targeted mutations of the juxtamembrane tyrosines in the Kit receptor tyrosine kinase selectively affect multiple cell lineages

Loss-of-function mutations in the murine dominant white spotting/c-kit locus affect a diverse array of biological processes and cell lineages and cause a range of phenotypes, including severe anemia, defective pigmentation, sterility, mast cell deficits, a lack of interstitial cells of Cajal, spatial learning memory deficits, and defects in peripheral nerve regeneration. Here we show that tyrosine residues 567 and 569 in the juxtamembrane (Jx) domain of the murine Kit receptor tyrosine kinase are crucial for the function of Kit in melanogenesis and mast cell development, but are dispensable for the normal development of erythroid, interstitial cells of Cajal and germ cells. Furthermore, adult mice lacking both tyrosines exhibit splenomegaly, dysregulation of B-cell and megakaryocyte development, and enlarged stomachs. Analysis of signal transduction events induced by the mutant receptors after ligand stimulation indicates that Jx tyrosine mutations diminish receptor autophosphorylation and selectively attenuate activation of extracellular signal-regulated kinase/mitogen-activated protein kinases. Together, these observations demonstrate that the Jx domain of Kit plays a cell-type specific regulatory role in vivo and illustrate how engineered mutations in Kit can be used to understand the complex biological and molecular events that result from activating a receptor tyrosine kinase.     

Antibody titer to gp210-C terminal peptide as a clinical parameter for monitoring primary biliary cirrhosis

BACKGROUND/AIMS: The presence of antibodies to the 210-kDa glycoprotein of the nuclear pore complex (gp210) is highly indicative of primary biliary cirrhosis (PBC). However, the significance of anti-gp210 antibody titers for monitoring PBC remains unresolved. METHODS: We used an ELISA with a gp210 C-terminal peptide as an antigen to assess serum antibody titers in 71 patients with PBC. RESULTS: Patients were classified into three groups: Group A in whom anti-gp210 titers were sustained at a high level, Group B in whom anti-gp210 status changed from positive to negative under ursodeoxycholic acid (UDCA) therapy, Group C in whom anti-gp210 antibodies were negative at the time of diagnosis. The rate of progression to end-stage hepatic failure was significantly higher in group A (60%) as compared to groups B (0%) and C (4.2%). The sustained antibody response to gp210 was closely associated with the severity of interface hepatitis. The significance of anti-gp210 antibody was confirmed by National Hospital Organization Study Group for Liver Disease in Japan. CONCLUSIONS: The serial quantitation of serum anti-gp210-C-terminal peptide antibodies is useful for monitoring the effect of UDCA and for the early identification of patients at high risk for end-stage hepatic failure.     

Synthesis of triazole- and tetrazole-xyloside analogues as potent hyaluronidase inhibitors

Hyaluronidase is one of the most important enzymes in the development of many diseases. In this study, a series of xyloside analogues bearing a triazole and tetrazole at the anomeric position were prepared from xylosylthioureas and evaluated their inhibitory effects on the hyaluronidase. Triazole and tetrazole skeletons were formed via the Hg(OAc)₂-mediated desulfurizative cyclization through carbodiimide intermediates. According to in vitro anti-hyaluronidase assay, tetrazole-xylosides having p-chloro- or p-nitro-substitution exhibited the high inhibition rates, whereas the compound having p-trifluoromethyl group on the structure did not show the potency. Our results demonstrated the importance of tetrazole-xylosides as hyaluronidase inhibitors.     

Long-term in vivo gene expression in mouse kidney using ϕC31 integrase and electroporation

Background: Achieving long-term gene expression in kidney will be beneficial for gene therapy of renal and congenital diseases, genetic studies constructing animal disease models, and the functional analysis of disease-related genes.

Purpose: The purpose of this study was to develop an in vivo long-term gene expression system in murine kidney using ?C31 integrase.

Methods: Gene expression in cultured RENCA, TCMK-1, and HEK293 cells was assessed. The long-term in vivo gene expression system in the kidney was achieved by co-transfecting 5?µg of pORF-luc/attB as a donor plasmid and 20?µg of pCMV-luc as a helper plasmid into the right kidney of mice by electroporation. Luciferase expression levels were measured to determine longevity of the expression.

Results: Significantly high luciferase expression levels were observed in cultured RENCA, TCMK-1, and HEK293 cells over 1 month compared with controls (non-integrase system). The luciferase cDNA sequence was integrated at a pseudo attP site termed mpsL1. In vivo luciferase expression levels in the integrase group were sustained and significantly higher than those in the control group over 2 months. Furthermore, ?C31 integrase-transfected cells had less genomic DNA damage caused by integrase expression.

Discussion and conclusion: These results demonstrated that the ?C31 integrase system could produce long-term (2 months) in vivo gene expression in mouse kidney.     

Clinical significance of left atrial geometry in dilated cardiomyopathy patients: A cardiovascular magnetic resonance study

BackgroundClinical significance of left atrial (LA) function and geometry in patients with dilated cardiomyopathy (DCM) remains uncertain.HypothesisLA geometric parameters assessed by cardiac magnetic resonance (CMR) predict the prognosis in patients with DCM.MethodsThe present study included patients with DCM and sinus rhythm who underwent CMR between December 2007 and April 2018. LA volume was measured using CMR. LA sphericity index was computed as the ratio of the measured maximum LA volume by the volume of a sphere with maximum LA length diameter.ResultsWe included 255 patients in this study. During the mean follow‐up of 3.92 years, hospitalization for HF occurred in 37 patients. The LA sphericity index was significantly higher in patients with hospitalization for HF than in those without (0.78 ± 0.35 vs. 0.58 ± 0.18, p < .001). Multivariable Cox regression analysis identified a higher LA sphericity index as an independent predictor of hospitalization for HF. Patients were categorized based on the median of LA sphericity index. The Kaplan–Meier curve showed that patients with a high LA sphericity index (≥0.57) had a significantly higher risk of hospitalization for HF than those with a low LA sphericity index (<0.57).ConclusionLA sphericity index was an independent predictor of hospitalization for HF. Assessment of LA geometric parameters might be useful for risk stratification in patients with DCM.     

Effects of functional movement screen training in high-school baseball players: A randomized controlled clinical trial

Background:In recent years, the functional movement screen (FMS) and FMS training have attracted attention as a means of preventing injury, but no studies have examined the effect of such training in high-school baseball players. The aim of this study was to clarify the effect of FMS training on FMS score, physical function and baseball performance in high-school baseball players.Methods:Subjects in this randomized controlled clinical trial were high-school male baseball players assigned to either an FMS training group (intervention group) or a control group. The intervention group performed FMS training 4 times per week for 12 weeks. FMS ability, physical function, and baseball performance were measured prior to the intervention, 8, 12, and 24 weeks after the intervention in the subjects’ school environment.Results:A total of 71 baseball players aged 15 to 17 years were recruited and assigned to either an intervention group (n = 37) or control group (n = 34). There was no significant difference in the characteristics of participants between the 2 groups. Most FMS scores improved to 12 weeks after continued training. In the intervention group compared with the control group, deep squat, hurdle step, inline lunge, active straight leg raise, trunk stability push-up and rotary stability FMS score, total FMS score and eyes closed single leg stance time significantly increased after 8 weeks of training. While hurdle step, inline lunge, active straight leg raise, trunk stability push-up, total FMS score, and eyes closed single leg stance time significantly increased, pitching ball speed significantly decreased at the end of the 12 week training period. Eyes closed single leg stance time and feeling of fatigue significantly improved 12 weeks after training. The number of subjects who scored less than 14 for the total FMS score in the intervention group compared with control group were significantly less after 8 and 12 weeks of FMS training.Conclusion:FMS training for 8 weeks contributes to improving FMS scores for high-school baseball players, but FMS scores go down if FMS training is not continued.Trial registration:University Hospital Medical Information Network Center, Tokyo, Japan: UMIN000027553. Registered on May 30, 2017.     

Neglect‐induced pseudo‐thrombotic thrombocytopenic purpura due to vitamin B12 deficiency

Although thrombotic thrombocytopenic purpura (TTP) is rare, early diagnosis and treatment are important for decreasing the mortality rate. Acquired vitamin B12 deficiency is frequently overlooked because of its rarity in developed countries, particularly in children and adolescents. The hematological changes in vitamin B12 deficiency present as megaloblastic anemia, increased lactate dehydrogenase, vasoconstriction, increased platelet aggregation, and abnormal activation of the coagulation followed by microangiopathy as well as neutropenia and thrombocytopenia. We report herein the case of a 15‐year‐old girl who had been neglected, which might have caused pseudo‐TTP through malnutrition, particularly vitamin B12 deficiency. When we encounter cases of TTP in children, clinicians must be aware of the possibility of malnutrition, particularly with vitamin B12 deficiency, even in developed countries, and investigate the cause of malnutrition including neglect.     

Microscopic observation of chemical modification in sections using scanning acoustic microscopy

A scanning acoustic microscope (SAM) calculates the speed of sound (SOS) through tissues and plots the data on the screen to form images. Hard tissues result in greater SOS; based on these differences in tissue properties regarding SOS, SAM can provide data on tissue elasticity. The present study evaluated whether tissue modifications, such as formalin fixation, periodic acid‐Schiff (PAS) reactions and protein degradation, changed the acoustic properties of the tissues and whether SAM could be a useful tool for following chemical changes in sections. The fixation process was observable by the increased SOS. During the PAS reaction, the glycosylation of tissues was characterized by an increased SOS. Mucous or glycogen distribution was visualized and was found to be statistically comparable among lesions and states. Protease digestion by pepsin led to a decreased SOS. Tissue sensitivity to proteases varied due to the stage, cause and duration of inflammation or ageing. Changes in acoustic properties were more sensitive than those in optical histology. SAM facilitates the visualisation of the time course or distribution of chemical modifications in tissue sections, thus aiding their comparison among tissues. SAM may be an effective tool for studying changes such as protein cross‐linkage, tissue repair and ageing.