184 research outputs found

    Liganded Thyroid Hormone Receptor Inhibits Phorbol 12-O-Tetradecanoate-13-Acetate-Induced Enhancer Activity via Firefly Luciferase cDNA

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    Thyroid hormone receptor (TR) belongs to the nuclear hormone receptor (NHR) superfamily and regulates the transcription of its target genes in a thyroid hormone (T3)-dependent manner. While the detail of transcriptional activation by T3 (positive regulation) has been clarified, the mechanism of T3-dependent repression (negative regulation) remains to be determined. In addition to naturally occurring negative regulations typically found for the thyrotropin β gene, T3-bound TR (T3/TR) is known to cause artificial negative regulation in reporter assays with cultured cells. For example, T3/TR inhibits the transcriptional activity of the reporter plasmids harboring AP-1 site derived from pUC/pBR322-related plasmid (pUC/AP-1). Artificial negative regulation has also been suggested in the reporter assay with firefly luciferase (FFL) gene. However, identification of the DNA sequence of the FFL gene using deletion analysis was not performed because negative regulation was evaluated by measuring the enzymatic activity of FFL protein. Thus, there remains the possibility that the inhibition by T3 is mediated via a DNA sequence other than FFL cDNA, for instance, pUC/AP-1 site in plasmid backbone. To investigate the function of FFL cDNA as a transcriptional regulatory sequence, we generated pBL-FFL-CAT5 by ligating FFL cDNA in the 5' upstream region to heterologous thymidine kinase promoter in pBL-CAT5, a chloramphenicol acetyl transferase (CAT)-based reporter gene, which lacks pUC/AP-1 site. In kidney-derived CV1 and choriocarcinoma-derived JEG3 cells, pBL-FFL-CAT5, but not pBL-CAT5, was strongly activated by a protein kinase C activator, phorbol 12-O-tetradecanoate-13-acetate (TPA). TPA-induced activity of pBL-FFL-CAT5 was negatively regulated by T3/TR. Mutation of nt. 626/640 in FFL cDNA attenuated the TPA-induced activation and concomitantly abolished the T3-dependent repression. Our data demonstrate that FFL cDNA sequence mediates the TPA-induced transcriptional activity, which is inhibited by T3/TR

    In Vivo and In Vitro Studies Suggest a Possible Involvement of HPV Infection in the Early Stage of Breast Carcinogenesis via APOBEC3B Induction

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    High prevalence of infection with high-risk human papilloma virus (HPV) ranging from 25 to 100% (average 31%) was observed in breast cancer (BC) patients in Singapore using novel DNA chip technology. Early stage of BC demonstrated higher HPV positivity, and BC positive for estrogen receptor (ER) showed significantly higher HPV infection rate. This unique association of HPV with BC in vivo prompted us to investigate a possible involvement of HPV in early stages of breast carcinogenesis. Using normal breast epithelial cells stably transfected with HPV-18, we showed apparent upregulation of mRNA for the cytidine deaminase, APOBEC3B (A3B) which is reported to be a source of mutations in BC. HPV-induced A3B overexpression caused significant γH2AX focus formation, and DNA breaks which were cancelled by shRNA to HPV18 E6, E7 and A3B. These results strongly suggest an active involvement of HPV in the early stage of BC carcinogenesis via A3B induction

    The sperm mitochondria-specific translocator has a key role in maternal mitochondrial inheritance.

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    The mechanism of maternal mitochondrial inheritance in animals involves the selective elimination of sperm mitochondria by the elimination factor of the egg and the sperm mitochondria-specific factor. In vitro fertilization using sperm from isogenic mice incorporating heterospecific mitochondrial DNA (mtDNA) showed that the number of PCR positives of sperm mtDNA in two-cell embryos was significantly increased following sperm incubation with anti-tetratricopeptide repeat-containing protein involved in spermatogenesis (tpis) protein, anti-translocator of mitochondrial outer membrane (Tom) 22 and anti-Tom40 antibodies. The treatment of fertilized eggs with EGTA and other endonuclease inhibitors increased the sperm mtDNA levels. We conclude that the elimination factor, which is probably an endonuclease, is selectively received by the tpis protein of the sperm mitochondrial outer membrane within the egg. It is then transported into the sperm mitochondria by Tom22 and Tom40, where it destroys the sperm mtDNA, establishing the maternal inheritance of mtDNA.The Version of Record (VoR) is available at http://www.cellbiolint.or

    Encapsulated Papillary Thyroid Tumor with Delicate Nuclear Changes and a Mutation as a Possible Novel Subtype of Borderline Tumor

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    Although papillary thyroid carcinoma (PTC)–type nuclear changes are the most reliable morphological feature in the diagnosis of PTC, the nuclear assessment used to identify these changes is highly subjective. Here, we report a noninvasive encapsulated thyroid tumor with a papillary growth pattern measuring 23 mm at its largest diameter with a nuclear score of 2 in a 26-year-old man. After undergoing left lobectomy, the patient was diagnosed with an encapsulated PTC. However, a second opinion consultation suggested an alternative diagnosis of follicular adenoma with papillary hyperplasia. When providing a third opinion, we identified a low MIB-1 labeling index and a heterozygous point mutation in the KRAS gene but not the BRAF gene. We speculated that this case is an example of a novel borderline tumor with a papillary structure. Introduction of the new terminology “noninvasive encapsulated papillary RAS-like thyroid tumor (NEPRAS)” without the word “cancer” might relieve the psychological burden of patients in a way similar to the phrase “noninvasive follicular thyroid neoplasm with papillary-like nuclear features (NIFTP).

    Stromal interaction molecule 1 haploinsufficiency causes maladaptive response to pressure overload

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    Stromal interaction molecule 1 (STIM1), an endo/sarcoplasmic reticulum Ca2+ sensor, has been shown to control a Ca2+- dependent signal that promotes cardiac hypertrophy. However, whether STIM1 has adaptive role that helps to protect against cardiac overload stress remains unknown. We hypothesized that STIM1 deficiency causes a maladaptive response to pressure overload stress. We investigated STIM1 heterozygous KO (STIM1(+/)-) mice hearts, in which STIM1 protein levels decreased to 27% of wild-type (WT) with no compensatory increase in STIM2. Under stress-free conditions, no significant differences were observed in electrocardiographic and echocardiographic parameters or blood pressure between STIM1(+/)-and WT mice. However, when STIM1(+/)-mice were subjected to transverse aortic constriction (TAC), STIM1(+/-) mice had a higher mortality rate than WT mice. The TAC-induced increase in the heart weight to body weight ratio (mean mg/g +/- standard error of the mean) was significantly inhibited in STIM1(+/-) mice (WT sham, 4.12 +/- 0.14; WT TAC, 6.23 +/- 0.40; STIM1(+/-) sham, 4.53 +/- 0.16; STIM1(+/-) TAC, 4.63 +/- 0.08). Reverse transcription- polymerase chain reaction analysis of the left ventricles of TAC-treated STIM1(+/-) mice showed inhibited induction of cardiac fetal genes, including those encoding brain and atrial natriuretic proteins. Western blot analysis showed upregulated expression of transient receptor potential channel 1 (TRPC1) in TAC-treated WT mice, but suppressed expression in TAC-treated STIM1(+/-) mice. Taken together, the hearts of STIM1 haploinsufficient mice had a superficial resemblance to the WT phenotype under stress-free conditions; however, STIM1 haploinsufficient mice showed a maladaptive response to cardiac pressure overload

    Combined subsegmentectomy: postoperative pulmonary function compared to multiple segmental resection

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    <p>Abstract</p> <p>Background</p> <p>For small peripheral c-T1N0M0 non-small cell lung cancers involving multiple segments, we have conducted a resection of subsegments belonging to different segments, i.e. combined subsegmentectomy (CSS), to avoid resection of multiple segments or lobectomy. Tumor size, location of tumor, and forced expiratory volume in 1 second (FEV<sub>1</sub>) of each preserved lobe were compared among the CSS, resection of single segment, and that of multiple segments.</p> <p>Methods</p> <p>FEV<sub>1 </sub>of each preserved lobe were examined in 17 patients who underwent CSS, 56 who underwent resection of single segment, and 41 who underwent resection of multiple segments, by measuring pulmonary function and lung-perfusion single-photon-emission computed tomography and computed tomography before and after surgery.</p> <p>Results</p> <p>Tumor size in the CSS was significantly smaller than that in the resection of multiple segments (1.4 ± 0.5 vs. 2.0 ± 0.8 cm, p = 0.002). Tumors in the CSS were located in the right upper lobe more frequently than those in the resection of multiple segments (53% vs. 5%, p < 0.001). Postoperative of FEV<sub>1 </sub>of each lobe after the CSS was higher than that after the resection of multiple segments (0.3 ± 0.2 vs. 0.2 ± 0.2 l, p = 0.07). Mean FEV<sub>1 </sub>of each preserved lobe per subsegment after CSS was significantly higher than that after resection of multiple segments (0.05 ± 0.03 vs. 0.03 ± 0.02 l, p = 0.02). There was no significant difference of these factors between the CSS and resection of single segment.</p> <p>Conclusions</p> <p>The CSS is effective for preserving pulmonary function of each lobe, especially for small sized lung cancer involving multiple segments in the right upper lobe, which has fewer segments than other lobes.</p

    Comparison of postoperative pulmonary function and air leakage between pleural closure vs. mesh-cover for intersegmental plane in segmentectomy

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    <p>Abstract</p> <p>Background</p> <p>To prevent postoperative air leakage after lung segmentectomy, we used two methods for the intersegmental plane: closing it by suturing the pleural edge (pleural closure), or opening it with coverage using polyglycolic acid mesh and fibrin glue (mesh-cover). The preserved forced expiratory volume in one second (FEV<sub>1</sub>) of each lobe and the postoperative air leakage were compared between the two groups.</p> <p>Methods</p> <p>For 61 patients who underwent pleural closure and 36 patients who underwent mesh-cover, FEV<sub>1 </sub>of the lobe before and after segmentectomy was measured using lung-perfusion single-photon-emission computed tomography and CT (SPECT/CT). The groups' results were compared, revealing differences of the preserved FEV<sub>1 </sub>of the lobe for several segmentectomy procedures and postoperative duration of chest tube drainage.</p> <p>Results</p> <p>Although left upper division segmentectomy showed higher preserved FEV<sub>1 </sub>of the lobe in the mesh-cover group than in the pleural closure one (<it>p </it>= 0.06), the other segmentectomy procedures showed no differences between the groups. The durations of postoperative chest drainage in the two groups (2.0 ± 2.5 vs. 2.3 ± 2.2 days) were not different.</p> <p>Conclusions</p> <p>Mesh-cover preserved the pulmonary function of remaining segments better than the pleural closure method in left upper division segmentectomy, although no superiority was found in the other segmentectomy procedures. However, the data include no results obtained using a stapler, which cuts the segment without recognizing even the intersegmental plane and the intersegmental vein. Mesh-cover prevented postoperative air leakage as well as the pleural closure method did.</p

    Evaluation of new prognostic staging systems (SLiDe score) for hepatocellular carcinoma patients who underwent hepatectomy.

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    BACKGROUND/AIMS: A new prognostic staging system, the SLiDe (S, stage; Li, liver damage; De, des-gamma-carboxy prothrombin) score was recently proposed. We examined 207 HCC patients following hepatic resection to determine the usefulness of this staging system for HCC patients after surgery. METHODOLOGY: Disease-free and overall survival rates were calculated according to the Kaplan-Meier method, and differences between groups were tested for significance using the log-rank test. RESULTS: Regarding disease-free survival, there were no significant differences in survival between SLiDe score 0 vs 1, between score 2 vs 3, and between score 4 vs 5. There were significant differences between 0-1 vs 2-3 (p < 0.01) and between 2-3 vs 4-5 (p < 0.01). Regarding overall survival, there were no significant differences in survival between score 0 vs 1, between score 2 vs 3, and between score 4 vs 5. There were significant differences between 0-1 vs 2-3 (p < 0.05) and between 2-3 vs 4-5 (p < 0.01). CONCLUSIONS: The SLiDe score, a staging system that combines tumor factors, a tumor marker and hepatic function, might be a better predictor of prognosis in HCC patients who have undergone hepatic resection

    Genome-Wide Association Study of Schizophrenia in Japanese Population

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    Schizophrenia is a devastating neuropsychiatric disorder with genetically complex traits. Genetic variants should explain a considerable portion of the risk for schizophrenia, and genome-wide association study (GWAS) is a potentially powerful tool for identifying the risk variants that underlie the disease. Here, we report the results of a three-stage analysis of three independent cohorts consisting of a total of 2,535 samples from Japanese and Chinese populations for searching schizophrenia susceptibility genes using a GWAS approach. Firstly, we examined 115,770 single nucleotide polymorphisms (SNPs) in 120 patient-parents trio samples from Japanese schizophrenia pedigrees. In stage II, we evaluated 1,632 SNPs (1,159 SNPs of p<0.01 and 473 SNPs of p<0.05 that located in previously reported linkage regions). The second sample consisted of 1,012 case-control samples of Japanese origin. The most significant p value was obtained for the SNP in the ELAVL2 [(embryonic lethal, abnormal vision, Drosophila)-like 2] gene located on 9p21.3 (p = 0.00087). In stage III, we scrutinized the ELAVL2 gene by genotyping gene-centric tagSNPs in the third sample set of 293 family samples (1,163 individuals) of Chinese descent and the SNP in the gene showed a nominal association with schizophrenia in Chinese population (p = 0.026). The current data in Asian population would be helpful for deciphering ethnic diversity of schizophrenia etiology
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