Clinicopathological features of colorectal polyps: evaluation of the 'predict, resect and discard' strategies

AIM

'Predict, resect and discard' strategies for diminutive and small colonic polyps are considered to be cost effective for treating colorectal cancers. The aim of this study was to determine, retrospectively, the histological features of colonic polyps resected by endoscopic procedures or surgery using an updated database.

METHOD

We retrospectively analysed the clinicopathological features of colorectal polyps, less than 20 mm in size, which were removed by endoscopy from January 2009 to November 2011 at the National Cancer Center Hospital (NCCH) in Tokyo, Japan.

RESULTS

Less than 1% of diminutive polyps (≤ 5 mm) were classified as mucosal high-grade neoplasia (Category 4), and no submucosal invasion by carcinoma (Category 5) lesions were noted. However, 3% of small polyps (6-9 mm) were classified as Category 5; of these, 6% were submucosal deep invasive cancers. Morphologically, depressed components were observed more frequently in carcinomas than in adenomas in both small and large polyps (10-20 mm).

CONCLUSION

In light of the 'predict, resect and discard' strategies for small polyps, we should pay attention to the possible clinical malignancy of small and large polyps. We recommend that these strategies should be applied selectively and that they should be informed by accurate endoscopic evaluations.

Mechanism of the dependence of hepatitis B virus genotype G on co-infection with other genotypes for viral replication

Hepatitis B virus (HBV) is classified into several genotypes. Genotype G (HBV/G) is characterised by worldwide dispersion, low intragenotypic diversity and a peculiar sequence of the precore and core region (stop codon and 36-nucleotide insertion). As a rule, HBV/G is detected in co-infection with another genotype, most frequently HBV/A2. In a previous in vivo study, viral replication of HBV/G was significantly enhanced by co-infection with HBV/A2. However, the mechanism by which co-infection with HBV/A2 enhances HBV/G replication is not fully understood. In this study, we employed 1.24-fold HBV/A2 clones that selectively expressed each viral protein and revealed that the core protein expressing construct significantly enhanced the replication of HBV/G in Huh7 cells. The introduction of the HBV/A2 core promoter or core protein or both genomic regions into the HBV/G genome showed that both the core promoter and core protein are required for efficient HBV/G replication. The effect of genotype on the interaction between foreign core protein and HBV/G showed that HBV/A2 was the strongest enhancer of HBV/G replication. Furthermore, Western blot analysis of Dane particles isolated from cultures of Huh7 cells co-transfected by HBV/G and a cytomegalovirus (CMV) promoter-driven HBV/A2 core protein expression construct indicated that HBV/G employed HBV/A2 core protein during particle assembly. In conclusion, HBV/G could take advantage of core proteins from other genotypes during co-infection to replicate efficiently and to effectively package HBV DNA into virions.

Fibrinogen γ-chain peptide-coated, ADP-encapsulated liposomes rescue thrombocytopenic rabbits from non-compressible liver hemorrhage

BACKGROUND

We developed a fibrinogen γ-chain (dodecapeptide HHLGGAKQAGDV [H12])-coated, ADP-encapsulated liposome (H12-[ADP]-liposome) that accumulates at bleeding sites via interaction with activated platelets via glycoprotein IIb-IIIa and augments platelet aggregation by releasing ADP.

OBJECTIVE

To evaluate the efficacy of H12-(ADP)-liposomes for treating liver hemorrhage in rabbits with acute thrombocytopenia.

METHODS

Thrombocytopenia (platelets < 50 000 μL(-1)) was induced in rabbits by repeated blood withdrawal (100 mL kg(-1) in total) and isovolemic transfusion of autologous washed red blood cells. H12-(ADP)-liposomes with platelet-poor plasma (PPP), platelet-rich plasma (PRP), PPP, ADP liposomes with PPP or H12-(PBS)-liposomes/PPP, were administered to the thrombocytopenic rabbits, and liver hemorrhage was induced by penetrating liver injury.

RESULTS

Administration of H12-(ADP)-liposomes and of PRP rescued all thrombocytopenic rabbits from liver hemorrhage as a result of potent hemostasis at the liver bleeding site, although rabbits receiving PPP or ADP liposomes showed 20% survival in the first 24 h. Administration of H12-(ADP)-liposomes and of PRP suppressed both bleeding volume and time from the site of liver injury. H12-(phosphate-buffered saline)-liposomes lacking ADP also improved rabbit survival after liver hemorrhage, although their hemostatic effect was weaker. In rabbits with severe thrombocytopenia (25 000 platelets μL(-1)), the hemostatic effects of H12-(ADP)-liposomes tended to be attenuated as compared with those of PRP treatment. Histologic examination revealed that H12-(ADP)-liposomes accumulated at the bleeding site in the liver. Notably, neither macrothombi nor microthrombi were detected in the lung, kidney or liver in rabbits treated with H12-(ADP)-liposomes.

CONCLUSIONS

H12-(ADP)-liposomes appear to be a safe and effective therapeutic tool for acute thrombocytopenic trauma patients with massive bleeding.

De novo ulcerative colitis and autoimmune hepatitis after living related liver transplantation from cytomegalovirus-positive donor to cytomegalovirus-negative recipient: a case report

BACKGROUND

De novo autoimmune hepatitis (AIH) after liver transplantation (OLT) has been reported; however, de novo ulcerative colitis (UC) combined with AIH after OLT is rare.

MATERIALS AND METHODS

We report a patient who suffered de novo UC with AIH after living related OLT (LRLT) due to fulminant hepatitis using a cytomegalovirus (CMV)-positive donor to a CMV-negative recipient.

RESULTS

A 32-year-old man underwent LRLT due to fuluminant hepatis 4 years prior. He was admitted for colitis with diarrhea, abdominal pain, and high fever in March 2010. The abdominal computed tomography revealed severe jejunal edema. Anti-infectious therapies for bacterial, fungal, and CMV cases were ineffective. Small bowel endoscopy demonstrated erosion, redness, ulceration, and edema from the stomach to the jejunum. However, the origin of the colitis was not clear. Thereafter he displayed melena with a high fever and abdominal pain. The colon revealed diffuse inflammation with pseudopolyposis. De novo UC or CMV infection was suspected. His symptoms improved upon administration of salazopyrin and denosine. Moreover, he suffered de novo AIH, which was diagnosed by liver biopsy 3 months after the de novo UC. Steroid therapy improved the AIH.

CONCLUSIONS

It has been reported that CMV is involved with UC and rejection. Our case suggested that CMV might induce de novo UC or AIH in CMV-negative recipients.

Magnetic compression anastomosis for bile duct stenosis after donor left hepatectomy: a case report

Magnetic compression anastomosis (MCA) provides a minimally invasive treatment creating a nonsurgical, sutureless enteric anastomosis in conjunction with an interventional radiologic technique by using 2 high-power magnets. Recently, the MCA technique has been applied to bile duct strictures after living donor liver transplantation or major hepatectomy. Herein we described use of MCA for bile duct stenosis 5 months after donor left hepatectomy in a 24-year-old man who presented with a stricture at the porta hepatis and intrahepatic bile duct dilatation. Unsuccessful transpapillary biliary drainage and balloon dilatation through a percutaneous transhepatic biliary drainage (PTBD) route led to the MCA. A 4-mm-diameter cylindrical samarium-cobalt (Sm-Co) daughter magnet with a long nylon wire was placed at the superior site of the obstruction through the PTBD route. A 5-mm-diameter Sm-Co parent magnet with an attached nylon handle was endoscopically inserted into the common bile duct and placed at the inferior site of obstruction. The 2 magnets were attracted, sandwiching the stricture and establishing a reanastomosis. In conclusion, the MCA technique was a unique procedure for choledochocholedochostomy in a patient with bile duct stenosis after donor hepatectomy.

Interleukin-33 induces interleukin-17F in bronchial epithelial cells

BACKGROUND

IL-33 is clearly expressed in the airway of patients with asthma, but its role in asthma has not yet been fully understood. IL-17F is also involved in the pathogenesis of asthma. However, the regulatory mechanisms of IL-17F expression remain to be defined. To further indentify the role of IL-33 in asthma, we investigated the expression of IL-17F by IL-33 in bronchial epithelial cells and its signaling mechanisms.

METHODS

Bronchial epithelial cells were stimulated with IL-33. The levels of IL-17F expression were analyzed using real-time PCR and ELISA. Next, the involvement of ST2, MAP kinases, and mitogen- and stress-activated protein kinase1 (MSK1) was determined by Western blot analyses. Various kinase inhibitors and anti-ST2 neutralizing Abs were added to the culture to identify the key signaling events leading to the expression of IL-17F, in conjunction with the use of short interfering RNAs (siRNAs) targeting MSK1.

RESULTS

IL-33 significantly induced IL-17F gene and protein expression. The receptor for IL-33, ST2, was expressed in bronchial epithelial cells. Among MAP kinases, IL-33 phosphorylated ERK1/2, but not p38MAPK and JNK. It was inhibited by the pretreatment of anti-ST2 neutralizing (blocking) Abs. MEK inhibitor significantly blocked IL-17F production. Moreover, IL-33 phosphorylated MSK1, and MEK inhibitor diminished its phosphorylation. Finally, MSK1 inhibitors and transfection of the siRNAs targeting MSK1 significantly blocked the IL-17F expression.

CONCLUSIONS

IL-33 induces IL-17F via ST2-ERK1/2-MSK1 signaling pathway in bronchial epithelial cells. These data suggest that the IL-33/IL-17F axis is involved in allergic airway inflammation and may be a novel therapeutic target.

Initial dose of vancomycin based on body weight and creatinine clearance to minimize inadequate trough levels in Japanese adults

Our aims were to elucidate the factors that affected vancomycin (VCM) serum trough levels and to find the optimal initial dose based on creatinine clearance (CrCl) and body weight (BW) to minimize inadequate trough levels in a retrospective observational study among Japanese adults. One hundred and six inpatients, in whom VCM trough levels were measured after completing the third dosing, were consecutively recruited into our study in a tertiary hospital. We considered the frequency of <30% as low. In the generalized linear model, initial VCM total daily dose, CrCl, and BW were independent risk factors of VCM trough levels. In patients with CrCl ≥30 and <50 mL/min, 1 g/day yielded low frequencies of a trough level of ≥20 mcg/mL, regardless of BW. In patients with CrCl ≥50 mL/min, 2 g/day yielded low frequencies of a trough level of <10 mcg/mL in patients weighing <55 kg, but not in patients weighing ≥55 kg. Optimal VCM initial total daily dose may be 1 g/day in patients with CrCl ≥30 and <50 mL/min regardless of BW and 2 g/day in patients weighing <55 kg with CrCl ≥50 mL/min among Japanese adults.

Blockade of cysteinyl leukotriene-1 receptors suppresses airway remodelling in mice overexpressing GATA-3

BACKGROUND

We demonstrated previously that GATA-3 overexpression markedly enhanced allergen-induced airway inflammation and airway remodelling, including subepithelial fibrosis, and smooth muscle cell hyperplasia, in transgenic mice.

OBJECTIVE

Because cysteinyl leukotrienes (cysLTs) have been shown to be involved in such structural changes, the effects of a specific cysLT1 receptor antagonist, montelukast, were evaluated in a mouse model of chronic asthma.

METHODS

GATA-3-overexpressing mice and wild-type Balb/c mice were sensitized and repeatedly challenged by ovalbumin (OVA) or saline. The effects of montelukast on the development of airway remodelling were compared between the two mouse genotypes.

RESULTS

CysLTs in the lung were increased after repeated allergen challenges, and significantly enhanced in GATA-3-overexpressing mice. The enhanced cysLT levels were accompanied by the development of eosinophilia, smooth muscle cell hyperplasia, and increased stromal cell-derived factor-1 gene expression with a small increase in pro-collagen gene expression in OVA-challenged GATA-3-overexpressing mice, but not in wild-type mice. Montelukast significantly decreased lung cysLT levels and inhibited the GATA-3-overexpression-related airway remodelling, potently preventing smooth muscle cell hyperplasia, but partially suppressed the increased pro-collagen gene expression and eosinophilic inflammation. Increases in the levels of IL-4, IL-5, IL-13, and eotaxin in bronchial lavage and TGF-β gene expression in the lungs were induced by OVA in both mouse genotypes. Montelukast treatment also significantly reduced these levels to the levels seen after saline challenges in GATA-3-overexpressing mice.

CONCLUSION

Montelukast efficaciously prevented airway inflammation and remodelling in a GATA-3-overexpression antigen challenge mouse model by decreasing the cysLT-driven Th2 cytokine cycle of amplification of airway pathologies.

Intraoperative electrophysiologic monitoring of ocular motor nerves under conditions of partial neuromuscular blockade during skull base surgery

The feasibility and usefulness of intraoperative electromyographic monitoring of the oculomotor nerve (CN III), trochlear nerve (CN IV), and abducens nerve (CN IV) were evaluated under conditions of partial neuromuscular blockade in 21 patients undergoing skill base surgery. Intracranial electrical stimulation of each nerve was performed, and compound muscle action potentials (CMAPs) were reconded from the inferior or superior rectus muscle, the superior oblique muscle, and the lateral rectus muscle for monitoring of CN III, IV, and VI, respectively. Partial neuromuscular blockade was achieved by controlled infusion of vecuronium titrated to eliminate about 90% of the twitch response of the abductor pollicis brevis to electrical stimulation of the median nerve. A total of 30 cranial nerves were stimulated intraoperatively. Of these, 29 were successfully monitored (19 CN III, 6 CN IV, 4 CN VI). A relationship was found between intraoperative findings of cranial nerve monitoring, such as disappearance of response and increase in latency and stimulus threshold during manipulation of a lesion, and the presence of postoperative nerve deficits. We conclude that intraoperative electromyographic monitoring of ocular motor nerves is feasible during partial neuromuscular blockade, and that partial neuromuscular blockade does not affect the relationship between findings of intraoperative monitoring and postoperative nerve function.

[Surgical therapy for left ventricular pseudoaneurysm]

Left ventricular pseudoaneurysm is a rare complication of myocardial infarction. However, the risk of rupture and heart failure are high, especially in a case of rapidly expanding aneurysm. As for left ventricular pseudoaneurysm, the risk of operation is high, and the long-term results are not good. We experienced 2 cases The 1st case was lost due to methicillin-resistant Staphylococcus aureus (MRSA) pneumonia The 2nd case is alive and has been free from heart failure for 3 years. The early diagnosis and surgery is necessary for a pseudoaneurysm.

Structural and Electrical Characterization of Undoped Poly-Si Oxides

We evaluated structural and electrical characteristics of undoped poly-Si oxide films. Poly-Si films made by solid phase crystallization at 600-900°C from undoped amorphous Si films were oxidized to form oxide layers of 140nm thickness. We observed protuberances on the surface of poly-Si layers after oxidation. Poly-Si oxide layers also generated protuberances above the protuberances of poly-Si films. The number of protuberances per unit area is larger in the case of high temperature crystallization. The measurement of current through the poly-Si oxide films shows that the conductivity of poly-Si oxide films depends on crystallization temperature of poly-Si films in the case of positive gate bias. When the gate is biased negatively, current through the poly-Si oxide films remained almost constant regardless of crystallization temperature. We find that poly-Si crystallized at lower temperatures offers poly-Si oxide films of lower leakage current in the case of electron injection from undoped poly-Si layers. The lower leakage current is due to highness of energy barrier for electron at undoped poly-Si/poly-Si oxide interface.

Isolation and characterisation of prolactin-releasing peptide in chicks and its effect on prolactin release and feeding behaviour

Prolactin (PRL)-releasing peptides (PrRP) have been identified in mammals, amphibians and fishes, and these animals have several PrRPs that consist of different numbers of amino acids such as 20, 31 and 37. In the present study, we identified the cDNA encoding chicken prepro-PrRP, which can generate putative PrRPs, and cloned and sequenced it. Sequences for the coding region suggested the occurrence of putative PrRPs of 20, 31 and 32 amino acid residues. The amino acid sequence of chicken PrRP20 showed 100%, 95% and 70% identity with those of PrRP20s from teleosts, Xenopus laevis and mammals, respectively. On the other hand, chicken PrRP31 showed approximately 90% and 52-55% homology to PrRP31s of X. laevis and mammals, respectively. Native chicken PrRPs were purified from an acid extract of chick brain by a Sep-Pak C18 cartridge (Waters Corp., Milford, MA, USA), affinity chromatography using anti-salmon PrRP serum, and reverse phase high-performance liquid chromatography (HPLC) on an ODS-120T column (TOSOH, Tokyo, Japan). The existence of chicken PrRP20 and PrRP31 in the brain was demonstrated by comparing them with the synthetic peptides using HPLC and matrix-assisted laser desorption/ionisation time-of-flight mass spectrometry. Chicken PrRP31 increased plasma PRL concentration when administered peripherally, whereas central administration decreased the concentration, suggesting that chicken PrRP31 has a distinct effect on PRL secretion between tissues in chicks. On the other hand, plasma growth hormone concentration decreased with both peripheral and central administrations of chicken PrRP31. Furthermore, central administration of chicken PrRP31 increased food intake in chicks compared to those observed in mammals and fishes. Taken together with the results indicating that chicken PrRP20 did not show endocrine and behavioural effects, we showed that chicken PrRP has a similar amino acid sequence to teleosts, Xenopus laevis and mammals, although the actions were variable among vertebrates.

[Senning operation for transposition of great arteries in a premature baby]

A male baby was delivered by emergency cesarean section due to fetal distress at 30 weeks of gestational age with a birth weight of 813 g. By fetal echocardiography, the patient had been diagnosed with transposition of great arteries (type 1). Early two-staged arterial switch operation was planned after 34 gestational age avoiding intracranial hemorrhage under cardiopulmonary bypass. At 19 days of life, vegetation was revealed on the pulmonary valve by echocardiography, so he was diagnosed as infectious endocarditis. Cefotaxime and gamma-globulin were given intravenously for 4 weeks. While waiting for the increase in the body weight, desaturation from chronic respiratory distress syndrome was exacerbated. At 8 months old, urgent Senning operation was performed to improve desaturation. The patient was discharged at 20 post operative day. We conclude that Senning operation can be feasible operation in such a complicated case.

Deposits on the intraluminal surface and bacterial growth in central venous catheters

Central venous catheter (CVC) tip and blood cultures are generally used to diagnose a catheter-related infection. Such methodology does not confirm the presence of bacterial colonisation on parts of CVCs other than the CVC tip. In order to assess the extent of bacterial colonisation, 10 catheters were examined in detail from patients admitted to intensive care unit. Swabs from the lumen at several sites (hub, indwelling and non-indwelling) were cultured and the intraluminal surface of the device subjected to scanning electron microscopy (SEM). Bacteria were detected on five out of 10 catheters (50%), and bacterial contamination of CVCs was common in the hub area of the device. Deposits (crystallisation) that differed from bacterial colonisation or biofilm were observed on the intraluminal surface of used CVCs. SEM showed bacteria firmly anchored to the deposits. Experimental flow studies demonstrated that deposits were more likely to appear after exposure to solutions such as total parenteral nutrition rather than distilled water. These deposits facilitated bacterial colonisation 30 times more than CVCs free from deposits.

Morphological characters and occurrence patterns of juveniles of two estuarine gobies, Acentrogobius kranjiensis and Acentrogobius malayanus, verified by molecular identification

Juveniles of two Acentrogobius species collected in a mangrove estuary in Sikao Creek, southern Thailand, were identified by morphological and molecular methods. A total of 1315 Acentrogobius specimens were collected and grouped into types A (n = 1107, 4.4-12.0 mm standard length, L(S)) (melanophore absent or indistinct on posterodorsal contour of caudal peduncle; two rows of melanophore blotches on lateral midline) and B (n = 208, 4.8-12.6 mm L(S)) (distinct melanophore on posterodorsal contour of caudal peduncle; a single row of melanophore blotches on lateral midline). Based on the reverse series method, the melanophore patterns of larger juveniles were linked with the smallest specimens possessing adult characters. The homogeneities of mitochondrial cytochrome b region sequences between the two juvenile types and adult Acentrogobius species collected in the study area indicated type A to be A. kranjiensis (homogeneity between type A and A. kranjiensis: 99.3-100%), and type B to be A. malayanus (homogeneity between latter 98.1 and 99.7%). No Acentrogobius juveniles were collected from the surf zone outside the creek mouth, both species apparently spending most of their life histories within the estuarine habitat. During their pelagic phase, A. kranjiensis and A. malayanus dispersed in the upper, middle and lower reaches of the creek. On the other hand, occurrence patterns during the benthic phase of A. kranjiensis and A. malayanus differed, the former showing upstream movement and the latter downstream movement with growth. These results emphasize the necessity of analysing early fish life histories at the species level, and the collaboration between morphological and molecular methods should prove valuable in accurately identifying of larvae and juveniles.

Establishment of a strain inheriting a sex-linked SNP marker in Patagonian pejerrey (Odontesthes hatcheri), a species with both genotypic and temperature-dependent sex determination

The Patagonian pejerrey Odontesthes hatcheri is an atherinopsid species presenting genotypic sex determination (GSD) at intermediate temperatures and temperature-dependent sex determination at the low and high ranges of thermal tolerance. A recent study revealed the presence of a sex-linked SNP marker in some males of this species, but a strain which inherits the marker faithfully has not been established. This research was conducted to develop such a strain, for use as a tool to study the molecular mechanisms of gonadal sex differentiation and sexual dimorphism, and to obtain basic information on the GSD mode in this species. For these purposes, we performed backcrosses and full-sibling crosses using males and females whose presumptive genotypic sex was inferred from the presence of the sex-linked SNP marker. Four backcrosses between SNP(-) daughters and their SNP(+) father generated balanced sex ratios with the phenotypic sex matching the genotypic sex in most cases (98.21%) at an intermediate, sexually neutral temperature (21 degrees C). Full-sibling crosses between these four SNP(-) females and their SNP(+) brothers produced three progenies with balanced sex ratios and one with 94.4% males. The results of this study confirm that a strain inheriting the sex-linked SNP marker was successfully developed. Moreover, the inheritance pattern of the marker and the sex ratios of the progenies provide strong evidence that the GSD mode in O. hatcheri is the XX-XY system.