Sequential compound exocytosis of large dense-core vesicles in PC12 cells studied with TEPIQ (two-photon extracellular polar-tracer imaging-based quantification) analysis

We investigated exocytosis of PC12 cells using two-photon excitation imaging and extracellular polar tracers (TEP imaging) at the basal region of PC12 cells adjacent to the glass cover slip. TEPIQ (two-photon extracellular polar-tracer imaging-based quantification) analysis revealed that most exocytosis was mediated by large dense-core vesicles (LVs) with a mean diameter of 220 nm, and that exocytosis of LVs occurred slowly with a mean latency of ∼7 s even though exocytosis was induced with large increases in cytosolic Ca²⁺ concentration by uncaging of a caged-Ca²⁺ compound. We also found that 97% of exocytic LVs remained poised at the plasma membrane, 72% maintained their fusion pores in an open conformation for more than 30 s, and 76% triggered sequential compound exocytosis of vesicles that were located deeper in the cytosol. Sequential compound exocytosis by PC12 cells was confirmed by electron microscopic investigation with photoconversion of diaminobenzidine by FM1-43 (a polar membrane tracer). Our data suggest that pre-stimulus docking of LVs to the plasma membrane does not necessarily hasten the fusion reaction, while docking and resulting stability of exocytic LVs facilitates sequential compound exocytosis, and thereby allowing mobilization of deep vesicles.     

Cytogenetic studies of Hynobiidae (Urodela) XIX. Morphological variation of sex chromosomes pairing behavior of sex lampbrush chromosomes in <Emphasis Type="Italic">Hynobius quelpaertensis</Emphasis> (Mori) from Cheju Island,South Korea

Using Giemsa staining, C-banding and Ag-NOR staining techniques, we analyzed chromosomes in adult male and female Hynobius quelpaertensis and in embryos of this species in egg sacs collected from eight localities of Cheju Island, South Korea. Chromosome pair 21 was consistently homomorphic in male specimens, while it was heteromorphic in female specimens, suggesting the occurrence of ZZ/ZW sex chromosome constitution in this species. The W chromosome, being much larger than the Z chromosome, was of three morphologically distinct types: W^A, W^B and W^C. Lampbrush chromosomes examined in the oocytes of one female specimen having the W^A chromosome showed that the short arm of the W^A chromosome and the long arm of the Z chromosome paired closely and hence are genetically homologous. We also tried to analyze the structural relationship among the three types of W chromosomes based on their C-banding and Ag-NOR patterns.     

Hereditary Apolipoprotein A-1 Amyloidosis With Glu34Lys Mutation Treated by Liver Transplantation: A Case Report

Hereditary apolipoprotein A-1 (ApoA-1) amyloidosis is a rare disease characterized by progressive deposition of amyloid fibrils in the kidney, heart, and liver. We observed a 45-year-old male patient with liver failure. Liver dysfunction was detected at 30 years of age during an annual health check-up. At 35 years of age, renal dysfunction was also found. At 40 years of age, the pathologic findings of the liver revealed amyloid deposition. A testis biopsy specimen taken at 42 years of age to identify the cause of male infertility showed amyloid accumulation. At 43 years of age, the amyloid results and genetic profile led to a definitive diagnosis of hereditary ApoA-1 amyloidosis caused by Glu34Lys mutation. A family history was absent. Liver failure showed Budd-Chiari–like formation, including enlargement of the caudate lobe and liver congestion. Although the patient showed end-stage liver cirrhosis and renal failure, only liver transplant was performed considering the burden for a living donor. The enlarged liver (4.9 kg) showed amyloid deposition in parenchyma and the space of Disse. Amyloid also accumulated in the giant spleen. The APOA1 mutation Glu34Lys is extremely rare, and in this case hepatic failure was successfully treated by liver transplant to both replace organ function and reduce production of the amyloidogenic ApoA-1–variant protein. Careful observation for reaccumulation of amyloidosis in the organ is required.     

A digest of the Evidence-Based Clinical Practice Guideline for Nephrotic Syndrome 2020

Clinical and Experimental Nephrology -     

Results of definitive radiotherapy with concurrent chemotherapy for maxillary sinus carcinomas with neck lymph node metastasis

The purpose of this study was to describe the results of definitive radiotherapy (RT) with concurrent chemotherapy for maxillary sinus carcinomas (MSCs) with neck lymph node metastasis to clarify its limitation. Local control (LC), progression-free survival (PFS) and overall survival (OS) rates were calculated using the Kaplan–Meier method and were compared between subgroups using the log rank test. Toxicity was classified using common terminology criteria of adverse events version 5.0. Eighteen patients with inoperable MSC with neck lymph node metastasis including 12 men and 6 women with a median age of 67 years were analyzed. The histologic diagnoses were as follows: 16 patients had squamous cell carcinomas and 2 had other histology. Four patients had stage T3 MSC, 6 had T4a and 8 had T4b. Among 18 patients, 7 received concurrent systemic chemotherapy and 11 received selective arterial chemo-infusion. The median follow-up period was 17 months. The 2-year LC, PFS and OS rates for the entire cohort were 34, 31 and 46%, respectively. No significant differences were observed for LC, PFS and OS rates between systemic chemotherapy and selective arterial chemo-infusion cohorts. Grade 3 or higher acute toxicity, including both non-hematological and hematological, was observed in nine patients (50%), while no grade 3 or higher late toxicity was observed. In conclusion, we described the results of definitive RT for MSCs with neck lymph node metastasis. Local recurrence of primary tumor was a frequent pattern of failure and it should be addressed in future study.     

Strain difference in transgene-induced tumorigenesis and suppressive effect of ionizing radiation

Transgenic expression in medaka of the Xiphophorus oncogene xmrk, under a pigment cell specific mitf promoter, induces hyperpigmentation and pigment cell tumors. In this study, we crossed the Hd-rR and HNI inbred strains because complete genome information is readily available for molecular and genetic analysis. We prepared an Hd-rR (p53^+/−, p53^−/−) and Hd-rR HNI hybrid (p53^+/−) fish-based xmrk model system to study the progression of pigment cells from hyperpigmentation to malignant tumors on different genetic backgrounds. In all strains examined, most of the initial hyperpigmentation occurred in the posterior region. On the Hd-rR background, mitf:xmrk-induced tumorigenesis was less frequent in p53^+/− fish than in p53^−/− fish. The incidence of hyperpigmentation was more frequent in Hd-rR/HNI hybrids than in Hd-rR homozygotes; however, the frequency of malignant tumors was low, which suggested the presence of a tumor suppressor in HNI genetic background fish. The effects on tumorigenesis in xmrk-transgenic immature medaka of a single 1.3 Gy irradiation was assessed by quantifying tumor progression over 4 consecutive months. The results demonstrate that irradiation has a different level of suppressive effect on the frequency of hyperpigmentation in purebred Hd-rR compared with hybrids.     

Are bladder washing samples suitable for investigation of HPV infection in urinary bladder? Comparison in HPV prevalence between urine and washing samples

Although urine and bladder washing samples are commonly used for the cytological evaluation of the bladder mucosa, it has been unknown whether these samples are likely suitable to investigate human papillomavirus (HPV) prevalence in the urinary bladder. The present study aimed to elucidate the appropriateness of spontaneously voided urine or bladder washing in screening HPV infection in the urinary bladder. Urine and bladder washing samples were obtained from 201 patients who underwent transurethral bladder tumor resection. After extracting DNA from both samples, HPV-DNA was examined using a nested polymerase chain reaction with GP5+/6+ and MY09/11 primers. HPV genotyping was performed in the HPV-positive samples. In situ hybridization (ISH) was performed to observe the HPV-DNA localization in urothelial cells among cytological samples and paraffin-embedded tumor tissues in HPV-positive washing samples. HPV prevalence in urine and washing samples were 9.5% and 7.0%, respectively. High-risk HPV prevalence in urine and washing samples was 7.5% and 4.0%, respectively. The most common HPV type was HPV 16, followed by HPV 52 and HPV 18 in both samples. HPV type distribution in both samples was not in agreement (κ = −0.431). The ISH analysis revealed that HPV-DNA signal was observed in urothelial cells of five (55.7%) of nine detectable HPV-positive cytological samples. Six (66.7%) of nine HPV-positive cases had HPV-DNA signals in tumor tissue. The use of washing samples was likely applicable for investigating HPV prevalence in the urinary bladder. HPV-DNA detected in washing samples might be frequently derived from the urinary bladder.     

Comprehensive genetic screening for vascular Ehlers–Danlos syndrome through an amplification-based next-generation sequencing system

Vascular Ehlers–Danlos syndrome (vEDS) is a hereditary connective tissue disorder (HCTD) characterized by arterial dissection/aneurysm/rupture, sigmoid colon rupture, or uterine rupture. Diagnosis is confirmed by detecting heterozygous variants in COL3A1. This is the largest Asian case series and the first to apply an amplification-based next-generation sequencing through custom panels of causative genes for HCTDs, including a specific method of evaluating copy number variations. Among 429 patients with suspected HCTDs analyzed, 101 were suspected to have vEDS, and 33 of them (32.4%) were found to have COL3A1 variants. Two patients with a clinical diagnosis of Loeys–Dietz syndrome and/or familial thoracic aortic aneurysm and dissection were also found to have COL3A1 variants. Twenty cases (57.1%) had missense variants leading to glycine (Gly) substitutions in the triple helical domain, one (2.9%) had a missense variant leading to non-Gly substitution in this domain, eight (22.9%) had splice site alterations, three (8.6%) had nonsense variants, two (5.7%) had in-frame deletions, and one (2.9%) had a multi-exon deletion, including two deceased patients analyzed with formalin-fixed and paraffin-embedded samples. This is a clinically useful system to detect a wide spectrum of variants from various types of samples.     

Therapeutic effect of a CDDP-epirubicin-Lipiodol emulsion on advanced hepatocellular carcinoma

Prior injection of an anticancer agent and Lipiodol mixture is a key point for the treatment of hepatocellular carcinoma (HCC). We therefore prepared a new, improved emulsion of Lipiodol containing a high dose ofcis-diamminedichloroplatinum (CDDP) and epirubicin by replacing the ionic contrast medium (Urografin 67) with a nonionic contrast medium (Iopamidol; Iopamiron 300) and adding phosphatidyl choline. This CDDP-epirubicin-Lipiodol emulsion (CELE) was examined pharmacologically and chemically with the following results. The size of these particles is less than 10 m (diameter) for up to 24 h; the release of 28%–34% of the CDDP and 80%–90% of the epirubicin was estimated in the dissolution test, and 85% of the CDDP and 35% of the epirubicin was retained in the organs in the moment calculation. CELE was injected into 58 HCC patients via a celiac angiographic catheter. In 36 of these patients, the CELE injection was followed by transcatheter arterial embolization (TAE) therapy. Following the administration of CELE as one-shot injection therapy for stage IV HCC, the 1-year survival rate was 59% and the 2-year survival rate was 27%. Moreover, in patients (stage II, 12; stage III, 8; stage IV, 16) who received CELE and subsequently underwent TAE therapy, the 1-year survival rate was 90% and the 2-year survival rate was 67%. The nonionic contrast medium with Lipiodol forms finer emulsified particles, and these particles are more capable of penetrating into the tumor. In addition, the greater pharmacological stability of these particles provides a slow-release effect and prolonged stability of their shape. Finally, theoretically, the use of two major anticancer agents such as CDDP and epirubicin showed a greater clinical effect in the treatment of HCC than either our earlier suspension or a single anticancer agent.Work presented at the Third International Symposium on Treatment of Liver Cancer, Seoul, Korea, 12–13 February 1993