Schwannoma of the esophagus: a case exhibiting high 18F-fluorodeoxyglucose uptake in positron emission tomography imaging

Esophageal schwannoma is rare and it is difficult preoperatively to confirm a definitive diagnosis, even using current imaging techniques. We present a case of a benign esophageal schwannoma that was surgically excised and confirmed by immunohistochemical staining. Conventional radiological studies, including barium meal, computed tomography and endoscopic examination had shown a solid submucosal tumor of the upper thoracic esophagus but had been unable to confirm the diagnosis. Positron emission tomography was carried out to evaluate the malignant potential and showed a high uptake of 18F-fluorodeoxyglucose (FDG) into the tumor in both the early and delayed phase, suggesting that the tumor was a potentially malignant tumor such as a gastrointestinal stromal tumor. This is the first reported case of esophageal schwannoma that indicated a high FDG uptake. Although consensus has not been reached regarding the precise mechanism of FDG accumulation in schwannomas, we discuss our clinicopathological findings and review other studies of the subject.

Validation of genotyping of gastrointestinal stromal tumor in Japan

e21502

Background: Most gastrointestinal stromal tumors (GIST) have activating mutations in the KIT or PDGFRA gene. Genotyping of GIST is important in Dx and Tx of GIST. Methods of genotyping using genomic DNA extracted from paraffin-embedded specimens are diverse and not standardized. We did validation study of genotyping using special reference to sequencing data obtained from cDNA from fresh GIST samples. Methods: Three DNA extraction methods (QIAamp, DEXPAT, or original) and four PCR methods (Ex Taq, AmpliTaq condition-1, AmpliTaq condition-2, or QIAGEN Tag) were compared using 20 paraffin-embedded specimens with special reference to sequencing data obtained from cDNA from corresponding 20 fresh GIST samples. After DNA extraction, KIT exon 9, 11, 13 and 17, and PDGFRA exon 12 and 18 were amplified by each PCR method using specific primers and directly sequenced. Results: In evaluation of PCR method, the protocol with Ex Taq showed 100% amplication of DNA and sequence agreement, the protocol with QIAGEN Tag 99%, and the protocol with AmpliTaq condition-2 86% agreement, and the protocol with AmpliTaq condition-1 showed much less amplication and higher disagreement. For the DNA extraction, the protocol with QIAamp showed best DNA extraction and its DNA sequence data were consistent with reference sequence in 98%, DNA sequence obtained using DEXPAT showed 33% consistency, and 89% of DNA sequence data obtained from an original method was agreed with reference data. Some modifications improved DNA amplication but inconsistent sequence data also increased probably due to miss-PCR. Conclusions: Each DNA extraction method had different quantity of DNA and four PCR methods showed different quality. Using this validation study, a standard genotyping method in Japan was established.

No significant financial relationships to disclose.

Silicon drain with channels along the sides for internal biliary stenting of hepaticojejunostomy in hepatic hilar malignancies

BACKGROUND

We compared two types of stents in patients who underwent surgery for hepatic hilar malignancies.

METHODS

Twenty-one patients with hepatic hilar malignancies who underwent hepatectomy were randomly assigned to one of two groups. A 5-Fr silicon drain with an internal lumen and side holes was used for the hepaticojejunostomy in one group (intraluminal stent group), and a 10-Fr silicon drain with channels along the sides was used in the other (channel stent group).

RESULTS

Leakage developed in four patients (36.4%) in the intraluminal stent group versus two (20.0%) in the channel stent group. Cholangitis developed in three patients with leakage (27.3%) in the intraluminal stent group versus no patient in the channel stent group. After operation, the times required for the serum alkaline phosphatase and total bilirubin levels to return to the normal range were significantly shorter in the channel stent group (5.3 +/- 2.9, 3.8 +/- 2.2 days) than in the intraluminal stent group (17.0 +/- 5.8, 9.4 +/- 5.7 days) (P < 0.0001, P = 0.0093).

CONCLUSION

A 10-Fr silicon drain with channels is superior to a 5-Fr silicon drain with an internal lumen for internal biliary stenting of hepaticojejunostomy in patients with hepatic hilar malignancies.

Curative resection of primary hepatic gastrinoma

Primary hepatic gastrinoma is very rare, with fewer than 20 cases reported. We describe a 44-year-old woman in whom primary hepatic gastrinoma was strongly suspected clinically. The patient was referred to our hospital because of intractable diarrhea. She had elevated serum levels of alanine aminotransferase, aspartate aminotransferase, and fasting gastrin. A calcium provocative test showed a marked elevated serum gastrin level (17,000 pg/ml). Abdominal ultrasonography, computed tomography, and magnetic resonance imaging revealed a tumor in the right lobe of the liver, measuring 38 x 33 mm. No other tumor was detected in the pancreas, duodenum, or local lymph nodes on preoperative radiological imaging or endoscopic ultrasonography. The hepatic tumor was resected. Total intraoperative ultra-sonography and intraoperative exploratory palpation of the duodenum, pancreas, and lymph nodes showed no evidence of an extrahepatic tumor. Pathological findings and immunohistochemical studies revealed a neuroendocrine tumor with increased production of gastrin. Postoperatively, the serum gastrin level returned to normal.

Chronic fatigue syndrome and the central nervous system

An increasing amount of neuroimaging evidence supports the hypothesis that chronic fatigue syndrome patients have structural or functional abnormalities within the brain. Moreover, some neurotrophic factors, neurotransmitters and cytokines have also been evaluated in order to elucidate the mechanism of abnormal neuropsychic findings in chronic fatigue syndrome. In this review, we suggest that the focal point of chronic fatigue syndrome research should be transferred to the central nervous system.

MicroRNA (miRNA) cloning analysis reveals sex differences in miRNA expression profiles between adult mouse testis and ovary

MicroRNAs (miRNAs) are endogenous non-coding small RNAs that can regulate the expression of complementary mRNA targets. Identifying tissue-specific miRNAs is the first step toward understanding the biological functions of miRNAs, which include the regulation of tissue differentiation and the maintenance of tissue identity. In this study, we performed small RNA library sequencing in adult mouse testis and ovary to reveal their characteristic organ- and gender-specific profiles and to elucidate the characteristics of the miRNAs expressed in the reproductive system. We obtained 10,852 and 11 744 small RNA clones from mouse testis and ovary respectively (greater than 10,000 clones per organ), which included 6630 (159 genes) and 10,192 (154 genes) known miRNAs. A high level of efficiency of miRNA library sequencing was achieved: 61% (6630 miRNA clones/10,852 small RNA clones) and 87% (10,192/11,744) for adult mouse testis and ovary respectively. We obtained characteristic miRNA signatures in testis and ovary; 55 miRNAs were detected highly, exclusively, or predominantly in adult mouse testis and ovary, and discovered two novel miRNAs. Male-biased expression of miRNAs occurred on the X-chromosome. Our data provide important information on sex differences in miRNA expression that should facilitate studies of the reproductive organ-specific roles of miRNAs.

A Novel Adipocytokine, Visceral Adipose Tissue-derived Serine Protease Inhibitor (Vaspin), and Obesity

Visceral adipose tissue-derived serine protease inhibitor (vaspin) is an interesting novel adipocytokine with insulin-sensitizing effects. Some studies have suggested that vaspin could play an important role in the development of obesity and metabolic disorders. The induction of vaspin mRNA expression could represent a compensatory mechanism associated with obesity, severe insulin resistance and type 2 diabetes mellitus, however it is unclear whether a correlation exists between human vaspin serum levels and markers of insulin sensitivity and glucose or lipid metabolism. Vaspin serum concentrations have been shown to be lower in lean subjects and competitive sportsmen with long-term physical training, but they are increased with weight loss associated with a physical training programme. In conclusion, there is at present no clear proof of a causal link between vaspin and visceral fat accumulation, or insulin resistance. This article reviews the role of vaspin in obesity-associated diseases and its potential as a new biomarker for obesity and impaired insulin sensitivity.

A mouse model of a human multiple GIST family with KIT-Asp820Tyr mutation generated by a knock-in strategy

Several families exhibiting multiple gastrointestinal stromal tumours (GISTs) and germline c-kit gene mutations at exons 8, 11, 13, or 17 have been reported. These patients also exhibit diffuse hyperplasia of the interstitial cells of Cajal (ICCs) as a pre-existing lesion of multiple GISTs. We generated a mouse model of a family with germline c-kit gene mutation at exon 17, and compared the phenotypes between the mice and humans. The mouse counterpart (KIT-Asp818Tyr) of the human KIT-Asp820Tyr mutation was transmitted into germline by a knock-in strategy. Mating of male and female heterozygotes (KIT-Asp818Tyr/+) resulted in the generation of homozygotes (KIT-Asp818Tyr/KIT-Asp818Tyr). Histological examination revealed that all heterozygotes had both a small KIT-positive mesenchymal tumour at the caecum, consistent with GIST, and KIT-positive diffuse spindle-shaped cell proliferation in the distal oesophagus, stomach, proximal duodenum, and colon consistent with ICC hyperplasia. All homozygotes exhibited a larger caecal tumour and more prominent spindle-shaped cell proliferation compared with the heterozygous mice, and they usually died within 10 weeks after birth, likely due to ileus. The small intestine of both genotypes showed no apparent morphological abnormality, and autonomous contraction of the ileal segments appeared normal. Western blotting demonstrated that the caecal tumours expressed phosphorylated KIT, MAPK, Stat1, and Stat5. These mutant mice are considered to be useful for further investigation of the mechanism of GIST development as a result of ICC hyperplasia and for assessment of the in vivo effects of drugs against molecular targets.

Pontine hypoplasia in children with periventricular leukomalacia

BACKGROUND AND PURPOSE

The brain stem in patients with periventricular leukomalacia (PVL) appears smaller than normal on MR imaging, but few reports have described this feature, and the number of patients has been relatively small. The present study was conducted to examine the hypothesis that the pons in patients with PVL is smaller than normal.

MATERIALS AND METHODS

Using MR imaging, we examined 80 children (43 boys and 37 girls) with PVL and 80 age-matched control children (41 boys and 39 girls). The control children were diagnosed as neurologically and developmentally normal by pediatric neurologists and also showed normal MR imaging findings. MR imaging was performed at a corrected age range of 0-5 years in both groups. We measured the anteroposterior diameter of the whole pons, the tegmentum and the basis, and the corpus callosal length by using midline T1-weighted sagittal images and compared each parameter between the PVL groups and the control groups.

RESULTS

Pontine diameters in all of the regions were significantly smaller in the PVL group than in the control group (mean +/- SD, whole pontine diameters, 1.66 +/- 0.21 and 1.87 +/- 0.23 cm [P < .001]; basis diameters, 0.42 +/- 0.10 and 0.51 +/- 0.14 [P < .001]; tegmentum diameters, 1.23 +/- 0.20 and 1.36 +/- 0.19 [P < .001], respectively). The respective corpus callosal lengths were 5.02 +/- 0.90 and 5.51 +/- 0.76 (P < .001). There was no significant difference in the basis/tegmentum ratio between the PVL group and the control group. When the age-related pontine diameter differences were examined, there was already a significant difference at 0 years of age between the 2 groups. There was a significant correlation between whole pontine diameter and corpus callosal length in the PVL group (correlation coefficient, 0.52; P < .001) and the control group (correlation coefficient, 0.63; P < .001).

CONCLUSION

We have proven that pontine diameter in patients with PVL is significantly smaller than that in normal control subjects, including each diameter of basis and tegmentum.

Tissue distribution of cynomolgus adeno-associated viruses AAV10, AAV11, and AAVcy.7 in naturally infected monkeys

Adeno-associated virus (AAV) is used in gene-therapy studies, but its tissue distribution is unknown in natural infection. We examined cynomolgus AAVs (previously isolated AAV10 and AAV11 and novel AAVcy.7) for their tissue distribution in 14 cynomolgi by type-specific PCR. We found AAV10, AAV11, and AAVcy.7 in 6, 10, and 14 monkeys, respectively, and two or three types in 11 monkeys, showing that these AAVs are widespread in the monkeys. We detected AAV at a higher level mainly in the lymphatic tissues and ileum, which suggests that AAV may invade the host through Peyer's patches in the ileum and infect immune cells.

Hop bract polyphenols reduced three-day dental plaque regrowth

Previous research has shown the inhibitory effects of hop bract polyphenols (HBP) on cariogenic streptococci in vitro, but their effects in humans have not been investigated. This double-blind, crossover clinical study tested the hypothesis that HBP delivered in a mouthrinse suppresses plaque regrowth in humans. Twenty-nine healthy male volunteers had all plaque removed, and refrained from all oral hygiene for 3 days, except for rinsing with a mouthrinse containing 0.1% HBP or a placebo. The results showed that the mean amount of plaque assessed by the Patient Hygiene Performance score after the volunteers used the HBP mouthrinse was significantly less than that after they used the placebo (p < 0.001). The number of mutans streptococci in the plaque samples after volunteers used the HBP mouthrinse was significantly lower than that after they used the placebo (p < 0.05). These findings suggested that HBP, delivered in a mouthrinse, successfully reduced dental plaque regrowth in humans.

PPARs and their metabolic modulation: new mechanisms for transcriptional regulation?

Peroxisome proliferator-activated receptors (PPARs) as ligand-activated nuclear receptors involved in the transcriptional regulation of lipid metabolism, energy balance, inflammation, and atherosclerosis are at the intersection of key pathways involved in the pathogenesis of diabetes and cardiovascular disease. Synthetic PPAR agonists like fibrates (PPAR-alpha) and thiazolidinediones (PPAR-gamma) are in therapeutic use to treat dyslipidaemia and diabetes. Despite strong encouraging in vitro, animal model, and human surrogate marker studies with these agents, recent prospective clinical cardiovascular trials have yielded mixed results, perhaps explained by concomitant drug use, study design, or a lack of efficacy of these agents on cardiovascular disease (independent of their current metabolic indications). The use of PPAR agents has also been limited by untoward effects. An alternative strategy to PPAR therapeutics is better understanding PPAR biology, the nature of natural PPAR agonists, and how these molecules are generated. Such insight might also provide valuable information about pathways that protect against the metabolic problems for which PPAR agents are currently indicated. This approach underscores the important distinction between the effects of synthetic PPAR agonists and the unequivocal biologic role of PPARs as key transcriptional regulators of metabolic and inflammatory pathways relevant to diabetes and atherosclerosis.

Feasibility of sequential fixed S-1 followed by paclitaxel for the treatment of advanced or recurrent gastric cancer

15113

Background: First-line chemotherapy for advanced/recurrent gastric cancer has limited efficacy, achieving a median survival time (MST) of about 7 months, while addition of second-line and subsequent chemotherapy may prolong MST to about 11.5 months. In practice, however, about half of patients failing with first-line chemotherapy are unable to receive second-line chemotherapy because of worsening of their performance status (PS), disease progression, or toxicities during protracted first-line chemotherapy. We studied the feasibility of a sequential fixed regimen devised to ensure prompt initiation of second-line chemotherapy after first-line failure. Methods: Between December 2002 and December 2006, patients with advanced or recurrent gastric cancer were enrolled who met the following requirements: 1) major organ function preserved; 2) PS 0–2; 3) presence of at least one evaluable lesion; and 4) written informed consent. The treatment regimen consisted of 3 courses of single-agent S-1 or S-1/cisplatin combination followed by weekly paclitaxel (wPTX). The endpoints of the study were entry to the second-line treatment, time to failure (TTF), and MST. Results: Of 39 patients enrolled, 37 completed first- line S-1. Twenty-eight patients (76%) then received wPTX, 2 non-wPTX chemotherapy, and 6 surgery; only 1 received no additional treatments. Second-line wPTX was followed by a third-line treatment in 23/28 patients (82%). The TTF with the sequential fixed regimen was 7 months. The MST and the 1- and 2-year survival rates in the 37 completing first-line treatment were 14.6 months, 61% and 25%, while those in the 28 switched over to wPTX were 12.5 months, 51% and 17%. Conclusions: Patients with advanced/recurrent gastric cancer treated sequentially with a fixed number of courses of S-1 followed by wPTX may have a good chance of treatment continuation. A sequential fixed regimen may further improve survival of patients with advanced/recurrent gastric cancer only with combinations of currently available drugs.

No significant financial relationships to disclose.

Expression of ephrin in retinal neovascularization and iris rubeosis

We investigated expression of ephrin-B2 and Eph-B4 in the retinal tissues of six primate eyes with neovascularization and iris rubeosis secondary to laser-induced central retinal vein occlusion and in tissue from 10 human eyes with proliferative diabetic retinopathy. Two primate eyes with rubeosis and retinal neovascularization were enucleated 1, 2 and 4 weeks after the creation of central retinal vein occlusion. Antibodies were localized using the avidin-biotin reaction. In the primate eyes, ephrin-B2 was negative at I week and positive at 2 and 4 weeks in the rubeotic tissue, but was positive only at 2 weeks in the retinal neovascular membrane. Eph-B4 was negative in all the primate eye specimens. In the human tissue, ephrin-B2 was detected in two of the five eyes with rubeosis and three of the five eyes with retinal neovascularization. These data suggest that ephrin-B2 is a key regulator of neovascularization.

Angiotensin-II receptor antagonist alleviates non-alcoholic fatty liver in KKAy obese mice with type 2 diabetes

We examined the effects of the angiotensin-II receptor antagonist candesartan on non-alcoholic fatty liver (NAFL) and circulating adiponectin concentrations in KKAy obese mice with type 2 diabetes mellitus. The KKAy mice were randomly assigned to receive either candesartan at a once-daily dose of 10 mg/kg (n = 5) or placebo (n = 5). The differences in liver weight, histological evaluation of hepatic lipid infiltration, serum adiponectin concentration and hepatic adiponectin mRNA levels between the two groups were determined on day 7 after treatment was initiated. Candesartan-treated mice demonstrated significantly lower liver weights and reduced lipid droplets in hepatic cells compared with control mice. The circulating adiponectin levels and hepatic expression of adiponectin mRNA were significantly higher in candesartan-treated mice than control mice. These results suggest that candesartan might alleviate NAFL through elevation of circulating adiponectin levels in KKAy obese mice with type 2 diabetes mellitus.

Germ line transformation of the silkworm, Bombyx mori, using the transposable element Minos

We investigated the use of Minos as a vector for transgenesis in the silkworm, Bombyx mori. We first constructed a vector plasmid with the green fluorescent protein (GFP) gene fused with the silkworm cytoplasmic actin gene (A3) promoter, and a helper plasmid with the Minos transposase gene controlled by the same A3 promoter. Injection of the vector and helper plasmid DNA into silkworm eggs produced transgenic animals in the following generation. The efficiency of transgenic silkworm production using this method was much lower than that obtained using piggyBac-mediated germ line transformation. However, >40-fold increase in the efficiency of producing transgenic silkworms was obtained using an in vitro synthesized source of Minos transposase mRNA. We conclude that the Minos transposon is a useful vector for construction of transgenic silkworms, particularly when in vitro synthesized mRNA is used. This is the first report showing that Minos can be used as a vector for germ-line transformation in lepidopteran insects.