Promoting Wound Healing Using Low Molecular Weight Fucoidan in a Full-Thickness Dermal Excision Rat Model

Low molecular weight fucoidan (LMF) has been reported to possess anti-inflammatory and antioxidant activities. Thus, we examined the effects of LMF extracted from Undaria pinnatifida on dermal wounds. Five round dermal wounds were created on the dorsal back of rats, and they were then treated topically with distilled water (DW), Madecasol Care™ (MC) or LMF at 200, 100 and 50 mg/mL, twice a day for a week. There were dose-dependent increases in wound contraction in the groups receiving LMF but not in the MC group, compared with the DW. Histopathological examination revealed that LMF treatment accelerated wound healing, which was supported by increases in granular tissue formation on day four post-treatment but a decrease on day seven, accompanied by an evident reduction in inflammatory cells. In the LMF-treated wounds, collagen distribution and angiogenesis were increased in the granular tissue on days four and seven post-treatment. Immunoreactive cells for transforming growth factor-β1, vascular endothelial growth factor receptor-2 or matrix metalloproteinases 9 were also increased, probably due to tissue remodeling. Furthermore, LMF treatment reduced lipid peroxidation and increased antioxidant activities. These suggested that LMF promotes dermal wound healing via complex and coordinated antioxidant, anti-inflammatory and growth factor-dependent activities.

Failure of Helicobacter pylori eradication and age are independent risk factors for recurrent neoplasia after endoscopic resection of early gastric cancer in 283 patients

BACKGROUND

Whether the incidence of metachronous gastric dysplasia and cancer could be decreased by eradication of Helicobacter pylori after endoscopic submucosal dissection (ESD) for early gastric cancer (EGC).

AIM

To compare the incidence of metachronous gastric lesion in the eradicated group and the persistent group. Second end point is to evaluate the risk factors for metachronous gastric lesions after ESD for EGC.

METHODS

In a single centre, between May 2007 and May 2010, the patients who had evidence of H. pylori infection at the time of ESD for EGC were included, and the follow-up data were analysed retrospectively.

RESULTS

We enrolled 283 patients who have shown H. pylori infection at the time of ESD for EGC. Successful eradication was achieved for 214 patients (75.6%) (Eradicated group), and 69 patients (24.4%) showed persistent H. pylori infection (Persistent group). Metachronous gastric lesions developed in 13 (18.8%) in the persistent group and 18 (8.4%) in the eradicated group (P = 0.016). In the ≥60-year-old group, the cumulative incidence of metachronous gastric cancer showed a significant increase (P = 0.012). Cumulative hazard ratio of subsequent gastric metachronous lesions differed between the eradication group and the persistent infection group (OR = 2.322, 95% CI = 1.136-4.744, P = 0.021), and ≥60 age at the time of endoscopic resection (OR = 2.803, 95% CI = 1.207-6.509, P = 0.016).

CONCLUSIONS

Both persistent H. pylori infection and old age (≥60) are independent risk factors for the increased incidence of metachronous gastric cancer.

Lentiviral modification of enriched populations of bovine male gonocytes

Undifferentiated germ cells have the capacity to develop into sperm capable of fertilizing oocytes and contributing genetic material to subsequent generations. The most primitive prepubertal undifferentiated germ cells include gonocytes and undifferentiated spermatogonia, including spermatogonial stem cells (SSC). Gonocytes, present in the testis at birth, differentiate into SSC, which maintain spermatogenesis for the remainder of the male's life. Because of their capacity to contribute to lifelong spermatogenesis, undifferentiated germ cells are attractive targets for genetic modification to produce transgenic animals, including cattle. To maximize the efficiency of genetic modification of bovine gonocytes and SSC, effective enrichment techniques need to be developed. Selection of bovine gonocytes using differential plating was improved 8-fold (P < 0.001) when using a combination of extracellular matrix proteins, including laminin, fibronectin, collagen type IV, and gelatin, compared to using laminin and gelatin alone. Selected cells labeled with PKH26 formed colonies of donor-derived germ cells after transplantation into recipient mouse testes, indicating putative stem cell function. Significantly more colonies (P < 0.001) per 1 × 10(5) viable transplanted cells were formed from isolated nonadherent cells (203 ± 23.2) compared to adherent (20 ± 2.7) or Percoll (45.5 ± 4.5) selected cells. After selection, some gonocytes were transduced using a lentiviral vector containing the transgene for the enhanced green fluorescent protein. Transduction efficiency was 17%. Collectively, these data demonstrate effective methods for the selection and genetic modification of bovine undifferentiated germ cells.

Unusual parotid gland lesions: a pictorial review

This is a pictorial essay of unusual parotid gland lesions that may be encountered in routine clinical practice.

Echo-endoscopy: new therapeutic frontiers

Endoscopic ultrasound (EUS) has been established as a valuable diagnostic modality as it offers high-resolution imaging and fine-needle biopsy, which is essential in detecting and staging malignancies. Since the introduction of EUS-guided fine needle aspiration (EUS-FNA) in 1992, numerous novel EUS-based interventions and techniques have emerged. Currently, established interventional EUS techniques include celiac plexus block and neurolysis, drainage of pancreatic pseudocysts and pelvic fluid collections, and implantation of fiducial markers and radioactive seeds into the malignant tumors. Emerging EUS-guided experimental techniques include antitumor injection, ablation of tumors, and vascular access. Diagnostic and therapeutic access to the biliary tree and pancreatic duct is increasingly being used for failed ERCP procedures or inaccessible ducts. Interventional EUS is a very promising technique with many potential applications. The future holds promise for substantial progress in EUS-guided therapeutic interventions and their applications in clinical gastroenterology.

The feasibility of endoscopic submucosal dissection for rectal carcinoid tumors: comparison with endoscopic mucosal resection

BACKGROUND AND STUDY AIMS

Rectal carcinoid tumors are often found incidentally during screening colonoscopy and can be resected using various endoscopic techniques. This study aimed to compare the safety and efficacy of endoscopic submucosal dissection (ESD) with endoscopic mucosal resection (EMR) for rectal carcinoid tumors.

PATIENTS AND METHODS

Between January 2003 and June 2009, 74 patients (74 lesions) underwent either EMR (n = 28) or ESD (n = 46) for rectal carcinoid tumors. The rate of endoscopic complete resection, pathological complete resection, procedure complications, and tumor recurrence were analyzed retrospectively.

RESULTS

The endoscopic complete resection rate was significantly higher in the ESD group (46 lesions, 100 %) compared with the EMR group (25 lesions, 89.3 %) ( P = 0.049). The pathological complete resection rate was higher in the ESD group (38 lesions, 82.6 %) compared with the EMR group (18 lesions, 64.3 %); however, this difference was borderline significant ( P = 0.067). Overall complication rate was not significantly different between the EMR group (3.6 %) and the ESD group (6.3 %). There was one case of remnant lesion in the EMR group, which was managed by ESD, and no recurrence has been detected in either the EMR or ESD groups.

CONCLUSION

This study suggests that ESD might be a feasible treatment technique for small rectal carcinoid tumors. It showed superior efficacy and comparable safety to EMR.

Where has the tumor gone? The characteristics of cases of negative pathologic diagnosis after endoscopic mucosal resection

BACKGROUND AND STUDY AIMS

Discrepancies can occur between the histopathological findings from forceps biopsy and endoscopic mucosal resection (EMR), and occasionally in embarrassing cases tumorous tissue is not found at EMR. The aim of the present study was to evaluate the clinical, endoscopic, and histological features of gastric tumors in patients with pathololgically negative findings at EMR.

PATIENTS AND METHODS

We retrospectively reviewed data from all patients with gastric tumor treated with EMR or endoscopic submucosal dissection (ESD) between August 1999 and April 2007 at our institution, and enrolled into the study patients with no tumor tissue found at mucosal resection. Their biopsy and EMR specimen slides were reviewed by a single pathologist. Patient characteristics, including demographic and clinical features, and the endoscopic appearance of mucosal lesions were evaluated.

RESULTS

Out of 633 patients treated with EMR or ESD, 20 patients (3.2 %) were included. The mean +/- SD maximal dimension of the mucosal lesions was 6.40 +/- 2.19 mm (range 3 - 10). Mean number of forceps biopsy fragments was 3.80 +/- 1.96 and mean sampling ratio was 2.08 +/- 1.07 mm/fragment. Before resection, histological findings from forceps biopsy were: 13 low grade dysplasias (65.0 %), 2 high grade dysplasias (10.0 %), and 5 intramucosal carcinomas (25.0 %).

CONCLUSIONS

In the case of pathologically negative findings at EMR, tumors might have been small enough to have been removed by the previous forceps biopsy. However, the possibility of sampling error or of a different location should be considered. Furthermore, appropriate communication between endoscopists and pathologists is essential.

Hyperglycaemia, hypercholesterolaemia and the risk for developing gastric dysplasia

BACKGROUND/GOALS

Gastric dysplasia is believed to be the penultimate stage of gastric carcinogenesis. Few studies have evaluated whether there is a relationship between such risk factors and gastric dysplasia. This case-control study was conducted to investigate the associations between obesity, serum glucose, lipids and gastric dysplasia.

STUDY

Endoscopic findings and pathology specimens were reviewed from 1 July 1997 to 31 December 2006 in the Health Promotion Center. One hundred thirty patients have the dysplasia in the stomach during screening endoscopy. The same number of controls was evaluated and matched to the gastric dysplasia group for age and gender.

RESULT

The univariate analysis showed that the dysplasia risk was slightly increased among persons with a higher low-density lipoprotein, lower high-density lipoprotein, impaired fasting glucose and higher total cholesterol. However, a higher body mass index and higher triglyceride level were not associated with the diagnosis of gastric dysplasia. In the multivariate-adjusted model, a higher low-density lipoprotein cholesterol and glucose were strongly associated with an increased risk of dysplasia compared to the controls. However, the body mass index, triglyceride and total cholesterol were not associated with the risk for dysplasia.

CONCLUSION

Hyperglycaemia and low-density lipoprotein cholesterol appear to be associated with the risk for gastric dysplasia. Further epidemiologic studies including a large cohort of patients with gastric dysplasia and adenocarcinoma are needed to clarify the association of low-density lipoprotein cholesterol, serum glucose and gastric carcinogenesis.

Factors related to lymph node metastasis and the feasibility of endoscopic mucosal resection for treating poorly differentiated adenocarcinoma of the stomach

BACKGROUND AND AIM

Endoscopic mucosal resection (EMR) is currently not accepted as an alternative treatment to surgery in early gastric cancer (EGC) of the undifferentiated histologic type. The present retrospective analysis examined the correlation of various histologic factors with the presence of lymph node metastasis (LNM).

PATIENTS AND METHODS

A retrospective analysis on 234 patients with poorly differentiated EGC who underwent radical gastrectomy with D2 lymph node dissection was undertaken. Several clinicopathologic factors were investigated to identify predictive factors for LNM: age, sex, type of operation, tumor location, tumor size, gross type, ulceration, lymphatic invasion, and depth of invasion.

RESULTS

Of the 234 lesions with poorly differentiated EGC, half (n = 116) already showed submucosal invasion in the resection specimen; 25.9 % of those (30/116) were limited to the upper third (SM1). Of the lesions confined to the mucosa, LNM was found in 3.4 % (4/118). With minor submucosal infiltration (SM1), the LNM rate was lower (0/30) in our patient population. Only with SM2/3 infiltration did the LNM rate sharply rise to around 30 %. The cut-off for submucosal infiltration depth was 500 microm (0/32 LNM), above which LNM rates were substantial (31.2 %; 24/77). There was limited correlation between the SM1-3 classification and actual measurement of submucosal infiltration depth. In a multivariate analysis, tumor size ( P = 0.033), depth of invasion ( P = 0.004), and lymphatic invasion ( P < 0.001) were associated with LNM.

CONCLUSION

Poorly differentiated EGC confined to the mucosa or with minimal submucosal infiltration (<or= 500 microm) could be considered for curative EMR due to the low risk of LNM. Given the limited case number of subgroups, these findings should be confirmed by more data from other centers, which should also focus on local recurrence after EMR in poorly differentiated EGC.

General and oral health implications of cannabis use

Cannabis, commonly known as marijuana, is the most frequently used illicit drug in Australia. Therefore, oral health care providers are likely to encounter patients who are regular users. An upward trend in cannabis use is occurring in Australia, with 40 per cent of the population aged 14 and above having used the drug. There are three main forms of cannabis: marijuana, hash and hash oil, all of which contain the main psychoactive constituent delta-9-tetrahydrocannabinol (THC). Cannabis is most commonly smoked, however it can be added to foods. THC from cannabis enters the bloodstream and exerts its effects on the body via interaction with endogenous receptors. Cannabis affects almost every system of the body, particularly the cardiovascular, respiratory and immune systems. It also has acute and chronic effects on the mental health of some users. Therefore, chronic abuse is a concern because of its negative effects on general physical and mental health. Cannabis abusers generally have poorer oral health than non-users, with an increased risk of dental caries and periodontal diseases. Cannabis smoke acts as a carcinogen and is associated with dysplastic changes and pre-malignant lesions within the oral mucosa. Users are also prone to oral infections, possibly due to the immunosuppressive effects. Dental treatment on patients intoxicated on cannabis can result in the patient experiencing acute anxiety, dysphoria and psychotic-like paranoiac thoughts. The use of local anaesthetic containing epinephrine may seriously prolong tachycardia already induced by an acute dose of cannabis. Oral health care providers should be aware of the diverse adverse effects of cannabis on general and oral health and incorporate questions about patients' patterns of use in the medical history.

New de-ubiquitinating enzyme, ubiquitin C-terminal hydrolase 8, in chick skeletal muscle

We have previously shown that chick muscle extracts contained at least 10 different ubiquitin C-terminal hydrolases (UCHs). Here we report the purification and characterization of one of the UCHs, called UCH-8, with 125I-labelled ubiquitin-alpha-NH-MHISPPEPESEEEEEHYC as a substrate. The purified UCH-8 behaved as a 240 kDa protein on a Superdex-200 column under non-denaturing conditions but as a 130 kDa polypeptide on analysis by PAGE under denaturing conditions, suggesting that the enzyme consists of two identical subunits. Thus this enzyme seems to be distinct in its dimeric nature from other purified UCHs that consist of a single polypeptide, except that UCH-6 is also a homodimer of 27 kDa subunits. UCH-8 was maximally active between pH 7.5 and 8, but showed little or no activity below pH 7 and above pH 9. Like other UCHs it was sensitive to inhibition by thiol-blocking agents such as N-ethylmaleimide, and by ubiquitin aldehyde. The purified UCH-8 hydrolysed not only ubiquitin-alpha-NH-protein extensions, including ubiquitin-alpha-NH-carboxy extension protein of 80 amino acid residues and ubiquitin-alpha-NH-dihydrofolate reductase, but also branched poly-ubiquitin that are ligated to proteins through epsilon-NH-isopeptide bonds. However, it showed little or no activity against poly-His-tagged di-ubiquitin, suggesting that UCH-8 is not involved in the generation of free ubiquitin from the linear poly-ubiquitin precursors. These results suggest that UCH-8 might have an important role in the production of free ubiquitin and ribosomal proteins from their conjugates as well as in the recycling of ubiquitin molecules after the degradation of poly-ubiquitinated protein conjugates by the 26 S proteasome.

Purification and characterization of a new ubiquitin C-terminal hydrolase (UCH-1) with isopeptidase activity from chick skeletal muscle

We have previously shown that chick muscle extracts contain at least 10 different ubiquitin C-terminal hydrolases (UCHs). In the present studies, one of the enzymes, called UCH-1 was partially purified by conventional chromatographic procedures using (125)I-labeled ubiquitin-alphaNH-MHISPPEPESEEEEEHYC as a substrate. The purified enzyme behaved as a 35-kDa protein under both denaturing and nondenaturing conditions, suggesting that it consisted of a single polypeptide chain. It was maximally active at pHs between 8 and 9, but showed little or no activity at pH below 6 and above 11. Like other UCHs, its activity was strongly inhibited by sulfhydryl blocking reagents, such as iodoacetamide, and by ubiquitin-aldehyde. In addition to Ub-PESTc, UCH-1 hydrolyzed ubiquitin-alphaNH-protein extensions, including ubiquitin-alphaNH-carboxyl extension protein of 80 amino acids, ubiquitin-alphaNH-dihydrofolate reductase, and poly-His-tagged di-ubiquitin. This enzyme was also capable of generating free ubiquitin from mono-ubiquitin-epsilonNH-protein conjugates and from branched poly-ubiquitin chains that are ligated to proteins through epsilon NH-isopeptide bonds. These results suggest that UCH-1 may play an important role in the generation of free ubiquitin from ubiquitin-ribosomal protein fusions and linear poly-ubiquitin, as well as in recycling of Ub molecules after degradation of poly-ubiquitinated protein conjugates by the 26S proteasome.

Multiple ubiquitin C-terminal hydrolases from chick skeletal muscle

A new method for assaying ubiquitin C-terminal hydrolases was developed using a 125I-labeled ubiquitin-alpha NH-MHISPPEPESEEEEEHYC was substrate. Since the peptide portion was almost exclusively radiolabeled, the enzymes could be assayed directly by simple measurement of the radioactivity released into acid-soluble products. Using this assay protocol, we identified at least 10 ubiquitin C-terminal hydrolase activities from the extract of chick skeletal muscle, which were tentatively named UCHs 1 through 10. Of these, UCH-6 was purified to apparent homogeneity. Purified UCH-6 behaved as a dimer of 27-kDa subunits. The apparent molecular masses of the other partially purified UCHs ranged from 35 to 810 kDa as determined under a non-denaturing condition. Muscle UCHs, except UCH-1, were activated dramatically by poly-L-Lys but with an unknown mechanism. All of the UCHs were sensitive to inhibition by sulfhydryl-blocking agents such as iodoacetamide. In addition, all of the UCHs were capable of releasing free ubiquitin from a ubiquitin-alpha NH-carboxyl extension protein of 80 amino acids and from ubiquitin-alpha NH-dihydrofolate reductase. Five of the enzymes, UCHs 1 through 5, were also capable of generating free ubiquitin from poly-His-tagged diubiquitin. In addition, UCH-1 and UCH-7 could remove ubiquitin that had been ligated covalently by an isopeptide linkage to a ubiquitin (RGA)-alpha NH-peptide, the peptide portion of which consists of the 20 amino acids of the calmodulin binding domain of myosin light chain kinase. These results suggest that the 10 UCH activities isolated from chick skeletal muscle appear to be distinct from each other at least in their chromatographic behavior, size, and substrate specificity.

Mycological survey of Korean cereals and production of mycotoxins by Fusarium isolates

The fungal species isolated from Korean cereals (barley, polished barley, wheat, rye, and malt) were Alternaria spp., Aspergillus spp., Chaetomium spp., Drechslera spp., Epicoccum sp., Fusarium spp., and Penicillium spp., etc. The number of Fusarium strains isolated was 36, and their ability to produce Fusarium mycotoxins on rice was tested. Nivalenol (NIV) was produced by Fusarium graminearum (7 of 9 isolates), Fusarium oxysporum (3 of 10 isolates), and Fusarium spp. (7 of 15 isolates). Of 15 isolates of Fusarium spp., 6 formed deoxynivalenol (DON). Fusarenon-X and 3-acetyl-DON were produced by most NIV- and DON-forming isolates, respectively. Zearalenone was produced by 3 isolates of F. graminearum, 1 isolate of Fusarium equiseti, and 11 isolates of Fusarium spp. T-2 toxin was not produced by any Fusarium isolates. The highest concentrations of mycotoxins produced by Fusarium isolates were 77.4 (NIV), 5.3 (DON), 138.3 (fusarenon-X), 40.6 (3-acetyl-DON), and 23.2 (zearalenone) micrograms/g.

Further survey on the Fusarium mycotoxins in Korean cereals

Fifty-one samples of cereals from the 1984 harvest from Korea were analyzed for nivalenol (NIV), fusarenon-X (FX), deoxynivalenol (DON) and 3-acetyl-DON by gas chromatography (GC) utilizing a 63Ni electron capture detector (ECD), and were quantitated for zearalenone (ZEN) by high-performance liquid chromatography (HPLC) with a fluorescence detector (FD). Trichothecenes and ZEN in the positive samples were confirmed by GC-mass spectrometry (MS). Out of 51 samples, 51, 46 and 42 were positive for NIV, DON and ZEN, respectively, and one malt sample was heavily contaminated with NIV (2675 ng/g) and DON (246 ng/g), and one wheat sample was heavily contaminated with NIV (3169 ng/g). Neither FX nor 3-acetyl-DON was detected in any of the samples. The data reported here indicates that Korean cereals harvested in 1984 are simultaneously contaminated with NIV, DON and ZEN, and the incidences and levels are similar to those observed in the cereals harvested in 1983.