Endoscopic resection after endoscopic hemostasis for hemorrhagic gastric cancer

A 68 years old man was referred to our hospital with symptoms of hematemesis and melena. An emergent gastroscopy showed a gastric ulcerative lesion with an exposed vessel (Forrest IIa) protruding from its base, which was located at the posterior wall of the upper portion of the gastric body. Endoscopic hemostasis was performed with endoclips and antiulcer treatment was done. Although the ulcerative lesion was healed two months after endoscopic hemostasis, the histopathological examination of the biopsy specimens revealed well differentiated adenocarcinoma (0-IIc). The tumor could be resected en-bloc by endoscopic submucosal dissection (ESD) without any complications such as perforation or postoperative bleeding. The resected specimen showed that the resected tumor was well differentiated intramucosal adenocarcinoma (13 x 10 mm) with a clear lateral margin. There was no recurrence during 12 months follow-up after ESD treatment. Follow-up endoscopy with biopsies should be performed for accurate diagnosis of gastric ulcerative lesions and ESD after endoscopic hemostasis with endoclips was an effective method for early gastric cancer presenting with massive hemorrhage in our case.     

Endoluminal MR imaging of porcine gastric structure in vivo

Background and aims

Recently, several new endoscopic instruments have been developed. However, even with the full use of current modalities, the safety of endoscopic surgery is not guaranteed. Information regarding factors such as fibrosis and the blood vessels under the mucosa is very important for avoiding procedure-related complications. The aim of this study was to define the detailed anatomy of the gastric wall structure in vivo using original endoluminal radiofrequency coils for safer endoscopic therapy.

Methods

Swine were used as the subjects and controlled with general anesthesia. Anatomical images were obtained with T1-weighted fast spin echo (T1FSE) and T2-weighted fast spin echo (T2FSE). Dynamic magnetic resonance (MR) angiography was also obtained with three-dimensional T1-weighted fast spoiled gradient recalled acquisition in the steady state (3D-DMRA) following the injection of hyaluronic acid sodium into the submucosal layer.

Results

Porcine gastric wall structure was visualized, and four layers were discriminated in the T1FSE and T2FSE images. The vascular structure was clearly recognized in the submucosa on 3D-DMRA.

Conclusion

Endoluminal MR imaging was able to visualize the porcine stomach with similar quality to endoscopic ultrasonography imaging. Additionally, it was possible to visualize the vascular structures in the submucosal layer. This is the first report to show that blood vessels under the gastric mucosa can be depicted in vivo.     

Establishment of an HIV cell-cell fusion assay by using two genetically modified HeLa cell lines and reporter gene

Infection of human cells with the human immunodeficiency virus type I (HIV-1) can be mimicked by a fusion process between cells expressing the HIV envelope protein (Env) and cells expressing both human CD4 together with the appropriate human chemokine receptors. In this study, a T-tropic HIV cell-cell fusion assay was established that utilized CD4, human CXCR4 and HIV NL4-3 gp160 as fusion components and a T7 polymerase-activated luciferase as a reporter system. The HeLa T4 cells used, expressed CD4 and CXCR4, and the applied HeLa KS386 cells expressed HIV NL4-3 gp160. By combining HeLa T4 cells with HeLa KS386 cells, an approximately about 100- to 300-fold increase in luciferase activity could be elicited relative to the control. The addition of anti-CD4 monoclonal antibody (Mab) (RPA-T4) or anti-CXCR4 Mab (12G5) in the assay significantly inhibited the fusion event; in contrast, an anti-CCR5 Mab (2D7) had no effect, indicating that the fusion assay was CD4 and CXCR4 dependent. In this report, fusion events could be monitored by both the luciferase reporter system and syncytia formation. Fusion events were monitored and compared using these two approaches. The luciferase reporter system was found to be more sensitive than syncytia formation. Moreover, compared with previous HIV fusion models, such as using recombinant vaccinia viruses, this system has several advantages, including simplicity and sensitivity. Finally, the system provides a powerful tool to study fusion mechanisms mediated by T-tropic HIV gp160, as well as to screen for fusion-blocking antibodies and antiviral agents.     

Protan color vision deficiency with a unique order of green–red as the first two genes of a visual pigment array

Normal visual pigment gene arrays on the human X chromosome have a red gene at the first and a green gene at the second positions. More than half of the arrays have additional green genes downstream, but only the first two genes of the array are likely to be expressed in the retina. An array consisting of four genes in two Japanese participants, A121 and A447, was detected either by pulsed field gel electrophoresis and subsequent Southern hybridization or by single nucleotide primer extension reaction. In both participants, the first gene of the array was green, downstream genes were red and green, and the fourth gene was green. The red gene was determined to be at the second position by comparison of polymorphic sites among the intergenic regions that had been amplified by long-range PCR. Such an array with a reverse normal order of pigment genes, green–red as the first two, has never been reported before. They were expected to have normal color vision but showed protan deficiency (protanomaly), a phenotype lacking the red pigment. The red gene had no mutations in the exons and exon/intron boundaries, but had an A−71C substitution in the promoter in both participants.     

Changing distribution of norovirus genotypes and genetic analysis of recombinant GIIb among infants and children with diarrhea in Japan

A total of 402 fecal specimens collected during July 2003-June 2004 from infants and children with acute gastroenteritis, encompassing five localities (Maizuru, Tokyo, Sapporo, Saga, and Osaka) of Japan, were tested for the presence of norovirus by RT-PCR. It was found that 58 (14.4%) fecal specimens were positive for norovirus. Norovirus infection was detected throughout the year with the highest prevalence in December. Norovirus GII was the most predominant genogroup (98.3%; 57 of 58). The genotypes detected in this study were GI/4, GII/2, GII/3, GII/4, and GII/6. Of these, NoV GII/3 (known as the Arg320 virus cluster) was the most predominant genotype (43.9%), followed by NoV GII/4 (the Lordsdale virus cluster; 35.1%) and others. Two norovirus strains clustered with a "new variant designated GIIb" and a "new variant of GII/4" were found circulating in Japan for the first time. It was interesting to note that NoV GIIb and NoV GII/3 appeared to be the recombinant strains and the recombination site was demonstrated at the overlap of ORF1 and ORF2. The majority (96%) of the dominant norovirus strains were identified as the recombination of GII/3 capsid and GII/12 polymerase. The recombination in the NoV GIIb capsid gene at the breakpoint located at P1 domain was also identified. Obviously, NoV GIIb isolate in Japan had double recombination. This is the first report demonstrating the existence of different "new variants" co-circulating in Japanese infants and children with acute gastroenteritis.     

Does increased nuchal translucency indicate a fetal abnormality? A retrospective study to clarify the clinical significance of nuchal translucency in Japan

The results of a chromosomal test by genetic amniocentesis in 58 cases with an increased nuchal translucency (NT; > or =3 mm thickness) revealed 47 cases showing a normal karyotype (81%) and 11 cases (19%) showing an abnormal karyotype. However, the cases of a normal karyotype with increased NT also included those with fetal abnormalities. Among the 49 cases in which NT was observed during the first trimester and then subsequently disappeared, chromosomal abnormalities were observed in five, and fetal abnormalities other than chromosomal abnormalities were observed in two. Meanwhile, all nine cases in which an increased NT remained or in which NT continued to increase in size during the second trimester were diagnosed as having cystic hygroma, and chromosomal abnormalities were found in six cases (67%). It should be noted that the shape of increased NT includes NT with a notch (notched NT) and NT without a notch (smooth NT). Among the 20 cases of notched NT, chromosomal abnormalities were observed in eight (40%), and cystic hygroma was observed in nine (45%). On the other hand, among the 38 cases of smooth NT, chromosomal abnormalities were observed in three (7.9%), but no cystic hygroma was observed. Our results confirm that increased NT does not always indicate a fetal abnormality. Whether NT thickness should be measured as a screening tool for fetal abnormalities remains controversial. However, increased NT may be detected by chance, because a maternal-fetal medical examination using ultrasonography is usually performed in Japan. It is therefore considered to be extremely important to establish a system in which cases are referred to obstetricians who are licensed clinical genetic specialists to obtain appropriate genetic counseling whenever increased NT is clinically observed.     

Shrinkage temperature and anti-calcification property of triglycidylamine-crosslinked autologous tissue

Since bioprosthetic valve dysfunction may arise due to histological calcification in the crosslinking process by glutaraldehyde (GA), non-GA crosslinking reagents have been investigated. We compared the efficacy of triglycidylamine (TGA), a newly synthesized epoxy compound, and GA as crosslinking reagents for the treatment of autologous tissues. We assessed the strength of crosslinked tissues using shrinkage temperature (Ts) measured by differential scanning calorimetry. We also conducted subdermal allografting of the crosslinked pericardium and thoracic aorta in rats, and verified the anti-calcification efficacy of TGA by histological evaluations with von Kossa stain, and immunological evaluations using tenascin-C (TN-C) or matrix metalloproteinase-9 (MMP-9). TGA treatment resulted in slower increases in Ts of the pericardium, and it required 9–12 h to reach Ts achieved by GA. In subdermal implantation of rat tissues, calcium content was lower in the TGA group than in the GA groups (p < 0.005). The expression site of TN-C and MMP-9 differed from the primary location of calcium deposition in the thoracic aorta treated with TGA suggesting a different underlying mechanism in calcification between GA and TGA crosslinking. In conclusion, TGA crosslinking in the allograft showed superior anti-calcification effect as compared to brief treatment by GA, although TGA crosslinking process was slow.     

Brain-derived neurotrophic factor-mediated retrograde signaling required for the induction of long-term potentiation at inhibitory synapses of visual cortical pyramidal neurons

High-frequency stimulation (HFS) induces long-term potentiation (LTP) at inhibitory synapses of layer 5 pyramidal neurons in developing rat visual cortex. This LTP requires postsynaptic Ca²⁺ rise for induction, while the maintenance mechanism is present at the presynaptic site, suggesting presynaptic LTP expression and the necessity of retrograde signaling. We investigated whether the supposed signal is mediated by brain-derived neurotrophic factor (BDNF), which is expressed in pyramidal neurons but not inhibitory interneurons. LTP did not occur when HFS was applied in the presence of the Trk receptor tyrosine kinase inhibitor K252a in the perfusion medium. HFS produced LTP when bath application of K252a was started after HFS or when K252a was loaded into postsynaptic cells. LTP did not occur in the presence of TrkB-IgG scavenging BDNF or function-blocking anti-BDNF antibody in the medium. In cells loaded with the Ca²⁺ chelator BAPTA, the addition of BDNF to the medium enabled HFS to induce LTP without affecting baseline synaptic transmission. These results suggest that BDNF released from postsynaptic cells activates presynaptic TrkB, leading to LTP. Because BDNF, expressed activity dependently, regulates the maturation of cortical inhibition, inhibitory LTP may contribute to this developmental process, and hence experience-dependent functional maturation of visual cortex.     

Molecular characterization of VP4, VP6, VP7, NSP4, and NSP5/6 genes identifies an unusual G3P[10] human rotavirus strain

An unusual strain of human rotavirus G3P[10] (CMH079/05) was detected in a stool sample of a 2‐year‐old child admitted to the hospital with severe diarrhea in Chiang Mai, Thailand. Analysis of the VP7 gene sequence revealed highest identities with unusual human rotavirus G3 strain CMH222 at 98.7% on the nucleotide and 99.6% on the amino acid levels. Phylogenetic analysis of the VP7 sequence confirmed that the CMH079/05 strain formed a cluster with G3 rotavirus reference strains and showed the closest lineage with the CMH222 strain. Analysis of partial VP4 gene of CMH079/05 revealed highest degree of sequence identities with P[10] rotavirus prototype strain 69M at nucleotide and amino acid levels of 92.9% and 94.6%, respectively. Phylogenetic analysis of the VP4 sequence revealed that CMH079/05 and 69M clustered closely together in a monophyletic branch separated from other rotavirus genotypes. To our knowledge, this is a novel G–P combination of G3 and P[10] genotypes. In addition, analyses of VP6, NSP4, and NSP5/6 genes revealed these uncommon genetic characteristics: (i) the VP6 gene differed from the four other known subgroups; (ii) the NSP4 gene was identified as NSP4 genetic group C, an uncommon group in humans; and (iii) the NSP5/6 gene was most closely related with T152, a G12P[9] rotavirus previously isolated in Thailand. The finding of uncommon G3P[10] rotavirus in this pediatric patient provided additional evidence of the genetic diversity of human group A rotaviruses in Chiang Mai, Thailand. J. Med. Virol. 81:176–182, 2009. © 2008 Wiley‐Liss, Inc.     

Acute effects of zolpidem on daytime alertness, psychomotor and physical performance

In a double-blind cross-over study, seven athletes received zolpidem (10mg) or placebo in two sessions over two nights. Residual effects on subsequent daytime functions were evaluated objectively by measuring psychomotor and physical performance using a combined test of finger dexterity, a simple discriminatory reaction test, critical flicker fusion test (CFF), vertical jump, and 50-m sprint, as well as subjectively, by visual analog scales. Zolpidem shortened self-estimated sleep latency and increased total sleep at nighttime. There was no change in alertness and fatigue scales on the following day in the zolpidem session, but realm of daytime well-being was slightly worsened. The CFF test showed significantly better results in the zolpidem group than in the placebo group. Zolpidem did not have effects in athletic evaluation. Zolpidem has a hypnotic activity without disturbing psychomotor and physical performance on the following day when given to healthy adults, suggesting zolpidem may be used in healthy athletes to adjust their extrinsic sleep disturbances and their consecutive psychomotor and physical impairments.