ATF7 mediates TNF-α-induced telomere shortening.

Telomeres maintain the integrity of chromosome ends and telomere length is an important marker of aging. The epidemiological studies suggested that many types of stress including psychosocial stress decrease telomere length. However, it remains unknown how various stresses induce telomere shortening. Here, we report that the stress-responsive transcription factor ATF7 mediates TNF-α-induced telomere shortening. ATF7 and telomerase, an enzyme that elongates telomeres, are localized on telomeres via interactions with the Ku complex. In response to TNF-α, which is induced by various stresses including psychological stress, ATF7 was phosphorylated by p38, leading to the release of ATF7 and telomerase from telomeres. Thus, a decrease of ATF7 and telomerase on telomeres in response to stress causes telomere shortening, as observed in ATF7-deficient mice. These findings give credence to the idea that various types of stress might shorten telomere.

Synthesis, Structure, Optical, and Electrochemical Properties of Triple- and Quadruple-Decker Co-facial Tetrathiafulvalene Arrays.

Understanding the details of the electronic structure in face-to-face arranged tetrathiafulvalenes (TTFs) is very important for the design of supramolecular functional materials and superior conductive organic materials. This article is a comprehensive study of the interactions among columnar stacked TTFs using trimeric (trimer) and tetrameric (tetramer) TTFs linked by alkylenedithio groups (-S(CH2 )n S-, n=1-4) as models of triple- and quadruple-decker TTF arrays. Single-crystal X-ray analyses of neutral trimeric TTFs revealed that the three TTF moieties are oriented in a zigzag arrangement. Cyclic voltammetry measurements (CV) reveal that the trimer and tetramer exhibited diverse reversible redox processes with multi-electron transfers, depending on the length of the -S(CH2 )n S- units and substituents. The electronic spectra of the radical cations, prepared by electrochemical oxidation, showed charge resonance (CR) bands in the NIR/IR region (1630-1850 nm), attributed to a mixed valence (MV) state of the triple- and quadruple-decker TTF arrays. In the trimeric systems, the dicationic state (+2; 0.66 cation per TTF unit) was found to be a stable state, whereas the monocationic state (+1) was not observed in the electronic spectra. In the tetrameric system, substituent-dependent redox processes were observed. Moreover, π-trimers and π-tetramers, which show a significant Davydov blueshift in the spectra, are formed in the tricationic (trimer) and tetracationic (tetramer) state. In addition, these attractive interactions are strongly dependent on the length of the linkage unit.

A Melanocytic Lesion Extending From the Right Ear to the Nasopharynx in a Pediatric Patient: A Case Report.

BACKGROUND: Blue nevus is a benign dermal melanocyte tumor that mainly arises from the skin. We report an extremely rare case of blue nevus in a pediatric patient with extensive progression from the middle ear and inner ear to the nasopharynx through the Eustachian tube. CASE REPORT: A 2-year-old girl with blue tympanum was referred to our department. Computed tomography scans and magnetic resonance imaging were performed, followed by a tissue biopsy and histopathologic evaluations. Radiologic examinations revealed that the lesion had progressed beyond the middle ear into the inner ear and the nasopharynx through the Eustachian tube. Subsequent histopathologic examinations indicated dermal dendritic melanocytic proliferations, but no evidence of malignancy. Based on the clinical and histopathologic findings, we concluded that the lesion was consistent with blue nevus. DISCUSSION: Blue nevus is a relatively common skin lesion. However, no prior reports have described the extension of blue nevus from the auditory organ to the nasopharynx in a pediatric patient. Despite the benign nature of the lesion, the patient experienced profound hearing loss in the affected ear, which necessitates continued monitoring as the lesion may expand with patient growth.

Maternal grafts protect daughter recipients from acute cellular rejection after pediatric living donor liver transplantation for biliary atresia.

Some studies have found that gender mismatch between donors and recipients are related to poor graft prognosis after liver transplantation. However, few studies have investigated the impact of gender mismatch on acute cellular rejection (ACR) in pediatric living donor liver transplantation (LDLT). This retrospective study investigated the clinical significance of these factors in ACR after pediatric LDLT. Between November 2001 and February 2012, 114 LDLTs were performed for recipients with biliary atresia (BA) using parental grafts. We performed univariate and multivariate analyses to identify the factors associated with ACR. The donor-recipient classifications included mother donor to daughter recipient (MD; n = 43), mother to son (n = 18), father to daughter (FD; n = 33), and father to son (n = 20) groups. The overall incidence rate of ACR in the recipients was 36.8%. Multivariate analysis showed that gender mismatch alone was an independent risk factor for ACR (P = 0.012). The FD group had a higher incidence of ACR than the MD group (P = 0.002). In LDLT, paternal grafts with gender mismatch were associated with a higher increased incidence of ACR than maternal grafts with gender match. Our findings support the possibility that maternal antigens may have an important clinical impact on graft tolerance in LDLT for patients with BA.

On the reaction-diffusion type modelling of the self-propelled object motion.

In this study, we propose a mathematical model of self-propelled objects based on the Allen-Cahn type phase-field equation. We combine it with the equation for the concentration of surfactant used in previous studies to construct a model that can handle self-propelled object motion with shape change. A distinctive feature of our mathematical model is that it can represent both deformable self-propelled objects, such as droplets, and solid objects, such as camphor disks, by controlling a single parameter. Furthermore, we demonstrate that, by taking the singular limit, this phase-field based model can be reduced to a free boundary model, which is equivalent to the [Formula: see text]-gradient flow model of self-propelled objects derived by the variational principle from the interfacial energy, which gives a physical interpretation to the phase-field model.

Rad51 suppresses gross chromosomal rearrangement at centromere in Schizosaccharomyces pombe.

Centromere that plays a pivotal role in chromosome segregation is composed of repetitive elements in many eukaryotes. Although chromosomal regions containing repeats are the hotspots of rearrangements, little is known about the stability of centromere repeats. Here, by using a minichromosome that has a complete set of centromere sequences, we have developed a fission yeast system to detect gross chromosomal rearrangements (GCRs) that occur spontaneously. Southern and comprehensive genome hybridization analyses of rearranged chromosomes show two types of GCRs: translocation between homologous chromosomes and formation of isochromosomes in which a chromosome arm is replaced by a copy of the other. Remarkably, all the examined isochromosomes contain the breakpoint in centromere repeats, showing that isochromosomes are produced by centromere rearrangement. Mutations in the Rad3 checkpoint kinase increase both types of GCRs. In contrast, the deletion of Rad51 recombinase preferentially elevates isochromosome formation. Chromatin immunoprecipitation analysis shows that Rad51 localizes at centromere around S phase. These data suggest that Rad51 suppresses rearrangements of centromere repeats that result in isochromosome formation.

Alcoholics show reduced telomere length in the oesophagus.

Telomeres are repetitive G-rich DNA sequences located at the ends of chromosomes. Chromosomal and genomic instability due to telomere dysfunction plays an important role in carcinogenesis. To study telomere shortening in the oesophageal epithelium of alcoholics, we measured the telomere lengths of basal and parabasal cells in comparison with those of non-alcoholics using Q-FISH and our original software, Tissue Telo, and also assessed histological inflammation. Telomeres in basal cells were significantly shorter in alcoholics than in age-matched normal controls. Prominent histological findings of chronic inflammation were not evident in either alcoholics or non-alcoholics. Our finding that telomeres in the oesophageal epithelium are shorter in alcoholics than in non-alcoholics indicates that telomere shortening may be associated with the frequent occurrence of squamous cell carcinoma in alcoholics. Further studies to clarify the reason for the large annual loss of telomere length with rapid turnover or lower telomerase activity in the oesophageal epithelium of alcoholics will be necessary.

Short telomeres in an oral precancerous lesion: Q-FISH analysis of leukoplakia.

OBJECTIVES: A precancerous condition is a lesion that, if left untreated, leads to cancer or can be induced to become malignant. In the oral region, leukoplakia is a lesion that has been regarded as precancerous. In cases of oral carcinoma, we have frequently noticed that a type of leukoplakia histologically demonstrating hyper-orthokeratosis and mild atypia (ortho-keratotic dysplasia; OKD) is often associated with carcinoma, either synchronously or metachronously. Therefore, we consider OKD-type leukoplakia to be a true precancerous lesion. MATERIALS AND METHODS: In an attempt to clarify the relationship between OKD as a precancerous condition in the oral mucosa and telomere length, we estimated telomere lengths in this type of leukoplakia using quantitative fluorescence in situ hybridization, and also quantified the frequency of anaphase-telophase bridges (ATBs) in comparison with squamous cell carcinoma in situ (CIS) and the background tissues of CIS and OKD. RESULTS: Ortho-keratotic dysplasia was frequently associated with squamous cell carcinoma (45.0%) and showed significantly shorter telomeres than normal control epithelium, CIS, or the background of CIS or OKD. The frequency of ATBs was much higher in OKD than in control epithelium or CIS. CONCLUSION: Ortho-keratotic dysplasia appears to be frequently associated with carcinoma, chromosomal instability, and excessively shortened telomeres, not only in the lesion itself but also in the surrounding background. Therefore, when this type of leukoplakia is recognized in the oral region, strict follow-up for oral squamous cell carcinoma is necessary, focusing not only on the areas of leukoplakia, but also the surrounding background.

Hepatocellular telomere length in biliary atresia measured by Q-FISH.

BACKGROUND: Liver transplantation for biliary atresia is indicated whenever a Kasai portoenterostomy is considered unfeasible. However, the timing of liver transplantation in biliary atresia has not been precisely defined. Excessive shortening of hepatocellular telomeres may occur in patients with biliary atresia, and therefore, telomere length could be a predictor of hepatocellular reserve capacity. METHODS: Hepatic tissues were obtained from 20 patients with biliary atresia who underwent LT and 10 age-matched autopsied individuals (mean age, 1.7 and 1.2 years, respectively). Telomere lengths were measured by Southern blotting and quantitative fluorescence in situ hybridization using the normalized telomere-centromere ratio. The correlation between the normalized telomere-centromere ratio for the hepatocytes in biliary atresia and the pediatric end-stage liver disease score was analyzed. RESULTS: The median terminal restriction fragment length of the hepatic tissues in biliary atresia was not significantly different from that of the control (p = 0.425), whereas the median normalized telomere-centromere ratio of hepatocytes in biliary atresia was significantly smaller than that of the control (p < 0.001). Regression analysis demonstrated a negative correlation of the normalized telomere-centromere ratio with the pediatric end-stage liver disease score in biliary atresia (p < 0.001). CONCLUSIONS: Telomere length analysis using quantitative fluorescence in situ hybridization could be an objective indicator of hepatocellular reserve capacity in patients with biliary atresia, and excessive telomere shortening supports the early implementation of liver transplantation.

[A case of cancer of the pancreatic tail with disseminated carcinomatosis of the bone marrow].

Disseminated carcinomatosis of the bone marrow derived from solid cancer has a very poor prognosis, with disseminated intravascular coagulation(DIC). A 72-year-old man was admitted to our hospital after detection of a tumor in the pancreatic tail by CT imaging. Several images revealed that he suffered from cancer of the tail of the pancreas with multiple liver and bone metastases. Endoscopic ultra-sonography-guided fine needle aspiration detected adenocarcinoma cells from the tumor of the pancreatic tail. We also performed bone marrow aspiration, which confirmed adenocarcinoma cells in the bone marrow. We started to administer 1,000 mg/m2 of gemcitabine weekly. Laboratory data revealed that thrombocytopenia had occurred, and it developed into DIC after the first the administration of gemcitabine. In spite of the DIC state with thrombocytopenia, we were able to provide anticancer treatment using combination gemcitabine and S-1. He recovered from his DIC state, and the primary tumor was shrunk with a decrease of tumor markers after 2 courses of combination chemotherapy. Chemotherapy might be required for disseminated carcinomatosis of the bone marrow in order to promote tumor shrinkage and to prolonged expected survival, even if DIC was developed.

Q-FISH analysis of telomere and chromosome instability in the oesophagus with and without squamous cell carcinoma in situ.

Chromosomal and genomic instability due to telomere dysfunction is known to play an important role in carcinogenesis. To study telomere dysfunction in the surrounding background epithelium of squamous cell carcinoma in situ (CIS) of the oesophagus, we measured telomere lengths of basal and parabasal cells of epithelia with and without CIS using quantitative fluorescence in situ hybridization (Q-FISH) and our original software, Tissue Telo. Additionally, we assessed histological inflammation and the anaphase bridge index. In non-cancerous epithelium, telomeres in basal cells were significantly longer than those in parabasal cells, whereas CIS showed a homogeneous telomere pattern in the basal and parabasal cells. Telomeres in basal and parabasal cells were significantly shorter in the background with CIS than in epithelium from age-matched normal controls. Significant negative correlation was observed between the normalized telomere : centromere ratio (reflected telomere length) and the anaphase bridge index in non-cancerous epithelia from both normal controls and the CIS background with no histological inflammation. These findings indicate that tissue stem cells may be located among basal cells, and that telomere length distribution in component cell types differs between CIS and non-cancerous epithelium. We have demonstrated conclusively that oesophageal CIS arises from epithelium with short telomeres and chromosomal instability in the absence of histological inflammation.

Telomere shortening in Barrett's mucosa and esophageal adenocarcinoma and its association with loss of heterozygosity.

OBJECTIVE: Telomere shortening is thought to be associated with genetic instability. The purpose of this study was to measure telomere length in a series of Barrett's adenocarcinomas (BAs), focusing on the telomere/centromere fluorescent intensity ratio (TCR) with tissue quantitative fluorescent in situ hybridization (Q-FISH). MATERIAL AND METHODS: A total of 11 cases of BA were evaluated for upper esophagus (UE), lower esophagus (LE), Barrett's mucosa (BM), BA, and gastric cardiac mucosa (GC). Q-FISH was performed using two kinds of peptide nucleic acid probe, specific for telomeres and centromeres. The sections were analyzed with a CCD camera and original software (Tissue Telo) for measuring TCR. In addition, Laser Capture Microdissection and GeneScan were implemented for evaluation of genetic instability. RESULTS: The TCR values in BM and, to a lesser extent, BA were significantly lower than those in the other tissues, particularly in heterozygosity (LOH)-positive cases. However, no significant difference was evident between microsatellite instability (MSI)-positive and -negative groups. CONCLUSIONS: In our study of BA series, telomere length appeared to change with the degree of histological atypia, with decreases linked to LOH.

[Cartilage palisade tympanoplasty for adhesive otitis media].

PURPOSE: We evaluated the clinical utility of cartilage palisade tympanoplasty (CRPT) in adhesive otitis media, a condition known to recur frequently with poor success in hearing gain. OBJECTIVE: Specimens were 9 ears having adhesive otitis media and undergoing CPT in January 2006 and December 2007. Cases of pars tensa cholesteatoma were excluded. Mean subject age was 35.2 years. Seven had total drum adhesion and 2 posterior half-adhesion. Preoperative pure-tone hearing averaged 20-102 dB (mean: 56 dB). METHODS: A small piece of cartilage harvested from the cymba was obliquely sectioned to yield wide, thin cartilage strips. Strips were overlapped slightly anteriorly to posteriorly parallel to the malleus handle when present. Tympanoplasty type 1 was conducted in 2 cases, type 3c in 6, and type 4c in 1. RESULTS: No ears undergoing CPT produced recurrent adhesion or perforation although 2 suffered transient partial erosion healed easily in topical management. An air-bone gap of <15 dB was achieved in 3 ears, a hearing gain exceeding 15 dB in 5, and a hearing level of less than 30 dB in 3. Conditions falling in at least 1 of the above categories are considered successful based on Japan Otological Society criteria. Seven of the 9 (78%) were regarded as audiologically successful. CONCLUSION: CPT conducted for adhesive otitis media appears worthwhile, given the present better-than-expected results in our cases, although further study is needed to confirm this conclusion.

[Telomere].

We reviewed correlations among telomere length, aging and carcinogenesis. Southern blot analysis showed that telomere shortening occurred with aging in all human tissues except for brain and myocardium. We investigated the telomere lengths of individual cell types in human tissues using a Q-FISH method and an original software package, "Tissue Telo". Q-FISH revealed that in squamous epithelia, NTCR corresponding to telomere length was significantly highest in basal cells and lowest in prickle cells, and that telomere length regressed at a certain rate in each cell type except for fibroblasts. Mean telomere length was significantly less in background tissue squamous epithelia of patients with cancer than in normal controls without cancer. We demonstrated telomere shortening and chromosomal instability in the background and normal control with excessively shortened telomeres. The data suggest that cancer arises from epithelial cells with short telomeres.

The teleost Oryzias latipes shows telomere shortening with age despite considerable telomerase activity throughout life.

Previous studies of telomeres and telomerase have focused mostly on mammals, and data for other vertebrates are limited. We analyzed both telomere length (terminal restriction fragment length) and telomerase activity in a small freshwater teleost fish, the medaka (Oryzias latipes), and found that the telomeres shorten during ageing despite the fact that a considerable amount of telomerase activity is ubiquitously detectable throughout the life of the fish. Since the telomere attrition rate during development was greater than that in adulthood, telomere length is inversely correlated with the increase in body length. The difference in telomere length among medaka individuals was similar to that in humans, and the individual specific differences were evident even at the earliest embryonic stage. Telomerase activity was ubiquitously detectable not only in the body of the embryo but also in the systemic organs of mature individuals throughout their entire life span. These data suggest that telomere attrition during ageing in medaka, which is similar to that in humans, may be a major factor determining their mortality, and that telomere maintenance through strong telomerase activity may be required for the characteristic lifelong continuous growth of this fish.

Correction to: Telomere length of gallbladder epithelium is shortened in patients with congenital biliary dilatation: measurement by quantitative fluorescence in situ hybridization.

In the original publication of this article, Fig. 5 was published with incorrect color of the approximate lines of CBD and Control.

Telomere length of gallbladder epithelium is shortened in patients with congenital biliary dilatation: measurement by quantitative fluorescence in situ hybridization.

BACKGROUND: Congenital biliary dilatation (CBD) is a congenital malformation involving both dilatation of the extrahepatic bile duct and pancreaticobiliary maljunction. Persistent reflux of pancreatic juice injures the biliary tract mucosa, resulting in chronic inflammation and higher rates of carcinogenesis in the biliary tract, including the gallbladder. Telomeres are repetitive DNA sequences located at the ends of chromosomes. Chromosomal instability due to telomere dysfunction plays an important role in the carcinogenesis of many organs. This study was performed to determine whether excessive shortening of telomeres occurs in the gallbladder mucosa of patients with CBD. METHODS: Resected gallbladders were obtained from 17 patients with CBD, ten patients with cholecystolithiasis without pancreatic juice reflux, and 17 patients with normal gallbladders (controls) (median age of each group of patients: 37, 50, and 53 years, respectively). The telomere lengths of the gallbladder epithelium were measured by quantitative fluorescence in situ hybridization using tissue sections, and the normalized telomere-to-centromere ratio (NTCR) was calculated. RESULTS: The NTCRs in the CBD, cholecystolithiasis, and control groups were 1.24 [interquartile range (IQR) 1.125-1.52], 1.96 (IQR 1.56-2.295), and 1.77 (IQR 1.48-2.53), respectively. The NTCR in the CBD group was significantly smaller than that in the cholecystolithiasis and control groups (p = 0.003 and 0.004, respectively), even in young patients. CONCLUSIONS: Our findings indicate that telomere shortening in the gallbladder mucosa plays an important role in the process of carcinogenesis in patients with CBD. These results support the recommendation of established guidelines for prophylactic surgery in patients with CBD because CBD is a premalignant condition with excessive telomere shortening.

Changes in telomere length with aging in human neurons and glial cells revealed by quantitative fluorescence in situ hybridization analysis.

AIM: The telomere is a structure present at the ends of chromosomes, and is known to shorten with aging and successive rounds of cell division. However, very little is known about telomere attrition in post-mitotic cells, such as neurons. METHODS: Using our originally developed quantitative fluorescence in situ hybridization method, we analyzed age-dependent alterations of telomere length in three types of cells in the human cerebrum: neurons and glial cells in both the gray and white matter. RESULTS: In adults, telomeres were significantly longer in neurons than in glial cells, whereas in infants, telomere lengths did not differ among the three cell types. No aging-related telomere attrition was evident in neurons. However, the telomeres of glial cells were shorter in older individuals than in younger individuals, and attrition was more rapid in the white matter than in the gray matter. CONCLUSIONS: The present results suggest that the telomeres of neurons remain stable throughout life, whereas telomeres in white matter glial cells become significantly shorter with age. Examination of adults showed no significant correlation between telomere length and age in the three cell types. Although the present study was cross-sectional, the results suggest that telomere shortening before adolescence contributes to the significant decrease of telomere length in white matter glial cells. The present findings in normal cerebral tissues will be informative for future studies of telomere stability in the diseased brain. Geriatr Gerontol Int 2018; 18: 1507-1512.

Regulation of DNA replication machinery by Mrc1 in fission yeast.

Faithful replication of chromosomes is crucial to genome integrity. In yeast, the ORC binds replication origins throughout the cell cycle. However, Cdc45 binds these before S-phase, and, during replication, it moves along the DNA with MCM helicase. When replication progression is inhibited, checkpoint regulation is believed to stabilize the replication fork; the detailed mechanism, however, remains unclear. To examine the relationship between replication initiation and elongation defects and the response to replication elongation block, we used fission yeast mutants of Orc1 and Cdc45--orp1-4 and sna41-928, respectively--at their respective semipermissive temperatures with regard to BrdU incorporation. Both orp1 and sna41 cells exhibited HU hypersensitivity in the absence of Chk1, a DNA damage checkpoint kinase, and were defective in full activation of Cds1, a replication checkpoint kinase, indicating that normal replication is required for Cds1 activation. Mrc1 is required to activate Cds1 and prevent the replication machinery from uncoupling from DNA synthesis. We observed that, while either the orp1 or the sna41 mutation partially suppressed HU sensitivity of cds1 cells, sna41 specifically suppressed that of mrc1 cells. Interestingly, sna41 alleviated the defect in recovery from HU arrest without increasing Cds1 activity. In addition to sna41, specific mutations of MCM suppressed the HU sensitivity of mrc1 cells. Thus, during elongation, Mrc1 may negatively regulate Cdc45 and MCM helicase to render stalled forks capable of resuming replication.