(1R*,2S*,4S*,5R*)-Cyclo­hexane-1,2:4,5-tetra­carb­oxy­lic dianhydride

The title compound, C10H8O6, a promising raw material to obtain colorless polyimides which are applied to microelectronic and optoelectronic devices, adopts a folded conformation in which the dihedral angle between the two anhydro rings is 55.15 (8)°. The central six-membered ring assumes a conformation inter­mediate between boat and twist-boat. In the crystal, mol­ecules are linked by weak C—H⋯O inter­actions, forming a layer parallel to the bc plane

Numerical Chromosome Aberrations In A Recurrent Malignant Fibrous Histiocytoma of the Retroperitoneum

Malignant fibrous histiocytoma (MFH) of the retroperitoneum is relatively rare in Japan. MFHs often recurs even if the tumor is resected completely. We describe a case with recurrent MFH of the retroperitoneum. A 49-year-old male was-admitted to our hospital for a palpable mass in the right lower abdomen. Ultrasonography and computed tomography demonstrated a solid mass with cystic compartment in the lower pole of the right kidney. The tumor was resected completely, and histological examination showed it was MFH, storiform-pleomorphic type. Thirty-three months later, a local recurrence developed and a second operation was performed. The resected tumor was 4.5 ﾃ・3.9 ﾃ・3.1 cm in size and histological diagnosis was recurrent MFH. We also examined the cytological characteristics of the tumor, using DNA flow cytometric quantification and fluorescence in situ hybridization (FISH) with a set of 14 chromosomespecific DNA probes. DNA contents showed a DNA diploid pattern, however, FISH analysis showed various aberrations of chromosome number such as +1, +2, +7, +8, -10, +11, +12, -16, -17, -18, and +20. These results suggested that chromosomal aberrations may reflect a higher biologic aggressiveness of recurrent MFH

Brown Adipose Tissue in Amyotrophic Lateral Sclerosis

The prevalence of brown adipose tissue (BAT) in the periadrenal adipose tissue was studied in 20 autopsy cases of amyotrophic lateral sclerosis (ALS). In 19 of 20 cases, the periadrenal BAT in focal or diffuse distribution was observed. Histometry of BAT revealed average occupancy rates of 21.6% and 4.2% in ALS and age-matched control cases, respectively (p<0.01). Since emaciation and chronic hypoxia in those ALS patients were most likely related to severe muscle wasting and respiratory involvement, it is speculated that an increase in BAT occupancy rates may be secondary to altered thermogenesis which was augmented by chronic hypoxia

Metagenomic analysis of bacterial species in tongue microbiome of current and never smokers

Cigarette smoking affects the oral microbiome, which is related to various systemic diseases. While studies that investigated the relationship between smoking and the oral microbiome by 16S rRNA amplicon sequencing have been performed, investigations involving metagenomic sequences are rare. We investigated the bacterial species composition in the tongue microbiome, as well as single-nucleotide variant (SNV) profiles and gene content of these species, in never and current smokers by utilizing metagenomic sequences. Among 234 never smokers and 52 current smokers, beta diversity, as assessed by weighted UniFrac measure, differed between never and current smokers (pseudo-F = 8.44, R² = 0.028, p = 0.001). Among the 26 species that had sufficient coverage, the SNV profiles of Actinomyces graevenitzii, Megasphaera micronuciformis, Rothia mucilaginosa, Veillonella dispar, and one Veillonella sp. were significantly different between never and current smokers. Analysis of gene and pathway content revealed that genes related to the lipopolysaccharide biosynthesis pathway in Veillonella dispar were present more frequently in current smokers. We found that species-level tongue microbiome differed between never and current smokers, and 5 species from never and current smokers likely harbor different strains, as suggested by the difference in SNV frequency

Lack of association of genetic variation in chromosome region 15q14-22.1 with type 2 diabetes in a Japanese population

Background: Chromosome 15q14-22.1 has been linked to type 2 diabetes (T2D) and its related traits in Japanese and other populations. The presence of T2D disease susceptibility variant(s) was assessed in the 21.8 Mb region between D15S118 and D15S117 in a Japanese population using a region-wide case-control association test. Methods: A two-stage association test was performed using Japanese subjects: The discovery panel (Stage 1) used 372 cases and 360 controls, while an independent replication panel (Stage 2) used 532 cases and 530 controls. A total of 1,317 evenly-spaced, common SNP markers with minor allele frequencies > 0.10 were typed for each stage. Captured genetic variation was examined in HapMap JPT SNPs, and a haplotype-based association test was performed. Results: SNP2140 (rs2412747) (C/T) in intron 33 of the ubiquitin protein ligase E3 component n-recognin 1 (UBR1) gene was selected as a landmark SNP based on repeated significant associations in Stage 1 and Stage 2. However, the marginal p value (p = 0.0043 in the allelic test, OR = 1.26, 95% CI = 1.07–1.48 for combined samples) was weak in a single locus or haplotype-based association test. We failed to find any significant SNPs after correcting for multiple testing. Conclusion: The two-stage association test did not reveal a strong association between T2D and any common variants on chromosome 15q14-22.1 in 1,794 Japanese subjects. A further association test with a larger sample size and denser SNP markers is required to confirm these observations

Gastritis Cystica Polyposa-Report of a Case

A case of gastritis cystica polyposa is presented. A 45-year-old woman developed gastritis cystica polyposa at the gastroduodenostomy anastomotic site four years after Billroth II gastrectomy for adenomatous polyp. There was no association of gastric cancer in the lesion

Lack of association of genetic variation in chromosome region 15q14-22.1 with type 2 diabetes in a Japanese population

<p>Abstract</p> <p>Background</p> <p>Chromosome 15q14-22.1 has been linked to type 2 diabetes (T2D) and its related traits in Japanese and other populations. The presence of T2D disease susceptibility variant(s) was assessed in the 21.8 Mb region between <it>D15S118 </it>and <it>D15S117 </it>in a Japanese population using a region-wide case-control association test.</p> <p>Methods</p> <p>A two-stage association test was performed using Japanese subjects: The discovery panel (Stage 1) used 372 cases and 360 controls, while an independent replication panel (Stage 2) used 532 cases and 530 controls. A total of 1,317 evenly-spaced, common SNP markers with minor allele frequencies > 0.10 were typed for each stage. Captured genetic variation was examined in HapMap JPT SNPs, and a haplotype-based association test was performed.</p> <p>Results</p> <p>SNP2140 (rs2412747) (<it>C/T</it>) in intron 33 of the ubiquitin protein ligase E3 component n-recognin 1 (<it>UBR1</it>) gene was selected as a landmark SNP based on repeated significant associations in Stage 1 and Stage 2. However, the marginal <it>p </it>value (<it>p </it>= 0.0043 in the allelic test, OR = 1.26, 95% CI = 1.07–1.48 for combined samples) was weak in a single locus or haplotype-based association test. We failed to find any significant SNPs after correcting for multiple testing.</p> <p>Conclusion</p> <p>The two-stage association test did not reveal a strong association between T2D and any common variants on chromosome 15q14-22.1 in 1,794 Japanese subjects. A further association test with a larger sample size and denser SNP markers is required to confirm these observations.</p

Early and long?term outcomes of endoscopic submucosal dissection for early gastric cancer in a large patient series

Endoscopic submucosal dissection (ESD) enables the curative resection of early gastric cancer (EGC); however, little information is available on the long-term outcomes of ESD. This study was conducted to clarify the clinical outcomes of a large number of patients with EGC who underwent ESD. The early outcomes were assessed in 1,209 patients and the long-term outcomes were assessed in 300 patients at a follow-up >5 years after the ESD procedure. The overall survival rates were compared between indication and expanded-indication groups, and between the patients who did or did not undergo additional surgery in an out-of-indication group. Overall survival rates were also compared among different age groups. In total, 617 lesions were classed as the indication group, 507 as the expanded-indication group and 208 as the out-of-indication group. Curative resection rates were 96.6% and 91.5% in the indication and expanded-indication groups, respectively. In terms of the long-term outcomes, 20 of the 146 patients in the indication group, 15 of the 105 patients in the expanded-indication group and one of the 23 patients who underwent additional surgery in the out-of-indication group succumbed due to causes other than gastric cancer. Among the 26 patients who did not undergo additional surgery in the out-of-indication group, 10 mortalities occurred, including one due to gastric cancer. The five-year survival rates were not significantly different between the indication and expanded-indication groups. In the out-of-indication group, the five-year survival rate for the patients who did not undergo additional surgery (65.0%) was significantly lower than that for those who did undergo additional surgery (100%) (P80 years (67.1%) was significantly lower than that of the younger patients (<60 years, 91.6%; sixties, 93.0%; seventies, 84.5%) (P<0.0001). In conclusion, although expanded-indication of ESD for EGC is appropriate, comorbidities require consideration in elderly patients

Genetic Evidence for Single-Strand Lesions Initiating Nbs1-Dependent Homologous Recombination in Diversification of Ig V in Chicken B Lymphocytes

Homologous recombination (HR) is initiated by DNA double-strand breaks (DSB). However, it remains unclear whether single-strand lesions also initiate HR in genomic DNA. Chicken B lymphocytes diversify their Immunoglobulin (Ig) V genes through HR (Ig gene conversion) and non-templated hypermutation. Both types of Ig V diversification are initiated by AID-dependent abasic-site formation. Abasic sites stall replication, resulting in the formation of single-stranded gaps. These gaps can be filled by error-prone DNA polymerases, resulting in hypermutation. However, it is unclear whether these single-strand gaps can also initiate Ig gene conversion without being first converted to DSBs. The Mre11-Rad50-Nbs1 (MRN) complex, which produces 3′ single-strand overhangs, promotes the initiation of DSB-induced HR in yeast. We show that a DT40 line expressing only a truncated form of Nbs1 (Nbs1p70) exhibits defective HR-dependent DSB repair, and a significant reduction in the rate—though not the fidelity—of Ig gene conversion. Interestingly, this defective gene conversion was restored to wild type levels by overproduction of Escherichia coli SbcB, a 3′ to 5′ single-strand–specific exonuclease, without affecting DSB repair. Conversely, overexpression of chicken Exo1 increased the efficiency of DSB-induced gene-targeting more than 10-fold, with no effect on Ig gene conversion. These results suggest that Ig gene conversion may be initiated by single-strand gaps rather than by DSBs, and, like SbcB, the MRN complex in DT40 may convert AID-induced lesions into single-strand gaps suitable for triggering HR. In summary, Ig gene conversion and hypermutation may share a common substrate—single-stranded gaps. Genetic analysis of the two types of Ig V diversification in DT40 provides a unique opportunity to gain insight into the molecular mechanisms underlying the filling of gaps that arise as a consequence of replication blocks at abasic sites, by HR and error-prone polymerases