Corticosteroids reduce pathologic interferon responses by downregulating STAT1 in patients with high-risk COVID-19

We do not yet understand exactly how corticosteroids attenuate hyperinflammatory responses and alleviate high-risk coronavirus disease 2019 (COVID-19). We aimed to reveal the molecular mechanisms of hyperinflammation in COVID-19 and the anti-inflammatory effects of corticosteroids in patients with high-risk COVID-19. We performed single-cell RNA sequencing of peripheral blood mononuclear cells (PBMCs) from three independent COVID-19 cohorts: cohort 1 was used for comparative analysis of high-risk and low-risk COVID-19 (47 PBMC samples from 28 patients), cohort 2 for longitudinal analysis during COVID-19 (57 PBMC samples from 15 patients), and cohort 3 for investigating the effects of corticosteroid treatment in patients with high-risk COVID-19 (55 PBMC samples from 13 patients). PBMC samples from healthy donors (12 PBMC samples from 12 donors) were also included. Cohort 1 revealed a significant increase in the proportion of monocytes expressing the long noncoding RNAs NEAT1 and MALAT1 in high-risk patients. Cohort 2 showed that genes encoding inflammatory chemokines and their receptors were upregulated during aggravation, whereas genes related to angiogenesis were upregulated during improvement. Cohort 3 demonstrated downregulation of interferon-stimulated genes (ISGs), including STAT1, in monocytes after corticosteroid treatment. In particular, unphosphorylated STAT-dependent ISGs enriched in monocytes from lupus patients were selectively downregulated by corticosteroid treatment in patients with high-risk COVID-19. Corticosteroid treatment suppresses pathologic interferon responses in monocytes by downregulating STAT1 in patients with high-risk COVID-19. Our study provides insights into the mechanisms underlying COVID-19 aggravation and improvement and the effects of corticosteroid treatment.

Learning curve of single-incision laparoscopic totally extraperitoneal repair (SILTEP) for inguinal hernia

PURPOSE

Laparoscopic totally extraperitoneal hernia repair (TEP) is a widely used treatment for inguinal hernia. Single-incision laparoscopic TEP (SILTEP) has attracted the attention of several surgeons, given its superior cosmetic results and patient satisfaction, as well as comparable outcomes to multiport surgery. Nonetheless, no relevant studies have evaluated the learning curve (LC) of SILTEP in terms of both operation time (OT) and surgical failure. Therefore, we aimed to investigate the LC of SILTEP for inguinal hernia.

METHODS

Medical records of 180 patients who underwent SILTEP performed by a single surgeon from a single institution between October 2012 and November 2017 were retrospectively reviewed. The LC was analyzed using the moving average method and cumulative sum control chart (CUSUM) for OT and surgical failure. Surgical failure was defined as the need for additional ports, open conversion, severe postoperative complications (Clavien-Dindo ≥ IIIa), and recurrence. Eight patients who underwent combined surgery or bilateral hernia repair were excluded from the OT analysis.

RESULTS

From CUSUM graphs, the study period was divided into three phases: OT-phases 1 (1st-32nd), 2 (33rd-83rd), and 3 (84th-172nd) for OT and failure-phases 1 (1st-29th), 2 (30th-58th), and 3 (59th-180th) for surgical failure. Mean OTs were statistically different in the three OT phases (64.6 vs. 50.8 vs. 35.2 min; p < 0.001). Open conversion (31.0% vs. 0% vs. 2.5%) and additional port insertion (6.9% vs. 24.1% vs. 2.5%) stabilized consecutively at failure-phases 2 and 3 (p < 0.001). Surgical failure rates decreased to 5.7% by failure-phase 3 (37.9% vs. 24.1% vs. 5.7%; p < 0.001).

CONCLUSION

For an experienced laparoscopic surgeon, we estimated that approximately 60 cases are needed to overcome the LC for SILTEP in terms of both reducing OT and achieving a surgical failure rate < 10%. Further proficiency could be achieved after approximately 85 SILTEP procedures with a stable OT of approximately 35 min.

Staufen1 and UPF1 exert opposite actions on the replacement of the nuclear cap-binding complex by eIF4E at the 5' end of mRNAs

Newly synthesized mRNAs are exported from the nucleus to cytoplasm with a 5′-cap structure bound by the nuclear cap-binding complex (CBC). During or after export, the CBC should be properly replaced by cytoplasmic cap-binding protein eIF4E for efficient protein synthesis. Nonetheless, little is known about how the replacement takes place. Here, we show that double-stranded RNA-binding protein staufen1 (STAU1) promotes efficient replacement by facilitating an association between the CBC–importin α complex and importin β. Our transcriptome-wide analyses and artificial tethering experiments also reveal that the replacement occurs more efficiently when an mRNA associates with STAU1. This event is inhibited by a key nonsense-mediated mRNA decay factor, UPF1, which directly interacts with STAU1. Furthermore, we find that cellular apoptosis that is induced by ionizing radiation is accompanied by inhibition of the replacement via increased association between STAU1 and hyperphosphorylated UPF1. Altogether, our data highlight the functional importance of STAU1 and UPF1 in the course of the replacement of the CBC by eIF4E, adding a previously unappreciated layer of post-transcriptional gene regulation.

Effect of drug compliance on health care costs in newly-diagnosed dementia: a nation-wide analysis

Background

The cost-effectiveness of both cholinesterase inhibitors and memantine by delaying nursing home placement has been supported by numerous studies. The importance of sustained pharmacological treatment in dementia has been relatively less recognized by public health policies compared to early diagnosis. We investigated the effect of the drug (donepezil, rivastigmine, galantamine, and memantine) compliance on the health care costs in newly-diagnosed dementia.

Methods

National Health Insurance Service (NHIS) database which covers the entire population of South Korea was used for analysis. Health care expenditure of patients newly-diagnosed with dementia in between 2012 and 2014 was investigated for 3 to 5 years. For drug compliance, we used Medication Possession Ratio (MPR) that indicates the percentage of time a patient has access to medication. Multivariate linear regression analysis including generalized estimated equation and gamma distribution was used for statistical analysis.

Results

We identified 252,594 patients who were both prescribed with cognitive enhancers and newly diagnosed with dementia. When initial MPR increased 20%, total health care costs decreased 8.4% (RR = 0.916, 95%; CI 0.914 to 0.916). Same relationship was shown with medical costs related to dementia, admission to a general hospital, and emergency room visits. When MPR increased 20% compared to the previous year, the total health care costs, admission to a general hospital, emergency room visits, and admission to a nursing hospital decreased.

Conclusions

This population-based retrospective cohort study provides evidence that patients newly-diagnosed with dementia who showed higher initial drug compliance or maintained antidementia drugs (Cholinesterase inhibitors and memantine) would benefit in total health-care costs.

Key messages

Public health care policies should not only focus on early diagnosis in dementia, but also recognize the importance of adherence to cognitive enhancers. To maximize the positive pharmacoeconomic effect of early diagnosis of dementia, it is important to sustain adequate drug compliance to cognitive enhancers.

Allium hookeri supplementation improves intestinal immune response against necrotic enteritis in young broiler chickens

Three hundred birds (1 day old) were randomly assigned to 6 groups (n = 50 birds/treatment) and fed a basal diet (control) or basal diet supplemented with Allium hookeri (AH) root (1 or 3%). At day 14, half of the birds in each group were orally challenged with E. maxima 41A (1 × 104 cells/chicken), followed by C. perfringens infection (1 × 109 cfu/chicken) on day 18. Necrotic enteritis (NE)-associated infections and intestinal immune response were assessed by average body weight gain, lesion score, and oocyst shedding. The effect of dietary supplementation, AH, on transcript levels of pro-inflammatory cytokines, and tight junction proteins and mucin protein in the jejunum, were quantified by quantitative real-time (qRT)-PCR. At day 20, birds fed with diet supplementation (3% of AH) significantly weighted more than the control group. Although the NE-challenged had significantly reduced average body weight gain, there was no significance in the effect between diet × NE-challenge interactions on the average body weight gain. Among the NE-challenged groups, gut lesion score and oocyst shedding were significantly decreased in birds given AH (1 or 3%) compared to the control group. There was a correlation between diet and NE infection with regards to interleukin (IL)-17A, and inducible nitric oxide synthase (iNOS). The up-regulated transcript levels of cytokines IL-8, IL-17A, iNOS, and LITAF by NE challenged groups were significantly reduced by AH (1 or 3%) supplementation. Down-regulated expression levels of tight junction (TJ) proteins: junctional adhesion molecule 2 (JAM2), occluding, and intestinal mucin 2 (MUC2) by NE challenge, was up-regulated by the addition of AH (1 or 3%) supplementation. All TJ proteins (JAM2, ZO1, Ocluddin and MUC2) in the jejunum had a significant diet × NE-challenge interaction. These findings demonstrate that dietary supplementation of AH in chicken feed could be beneficially used to improve chicken health against NE.

The Effects of Direct-fed Microbial Supplementation, as an Alternative to Antibiotics, on Growth Performance, Intestinal Immune Status, and Epithelial Barrier Gene Expression in Broiler Chickens

The objective of this study was to investigate the effects of Bacillus subtilis-based probiotic supplementation in broiler chicken diets on growth performance, feed efficiency, intestinal cytokine, and tight junction (TJ) protein mRNA expression. Zero-day-old broiler chicks (n = 140) were randomly assigned to one of five dietary treatments: basal diet (CON); basal diet supplemented with either antibiotic bacitracin methylene disalicylate (BMD); or probiotics, namely, B. subtilis strain 1781 (PB1), a combination of B. subtilis strain 1104 + strain 747 (PB2), or B. subtilis strain 1781 + strain 747 (PB3). Body weight and feed intake were measured at 14 days of age, and the feed conversion ratio (FCR) was calculated. At 14 days of age, ileal samples were collected and used for intestinal cytokine, TJ protein, and mucin gene expression analysis using qRT-PCR. The chickens supplemented with antibiotic (BMD) and B. subtilis strain 1781 alone (PB1) had significantly higher body weights compared to controls of the same age. Dietary supplementation with antibiotic (BMD) or probiotics (PB1, PB2, PB3) significantly improved the feed efficiency as evidenced by decreased FCR compared to controls. No differences were observed in the expression of IL1β, IL17F, IFNγ, and MUC2 gene among the different treatment groups. However, elevated expression of IL6 (BMD, PB1, PB2), IL8 (PB2), and TNFSF15 (PB1, PB2, PB3) compared to controls was observed in the ileum. IL2 and IL10 expression was upregulated in chicks in the PB2 and PB3 groups, and IL4 was elevated in the PB1 group. IL13 was elevated in all probiotic-fed groups (PB1, PB2, PB3). Probiotic supplementation was also shown to significantly increase the expression of TJ proteins JAM2, ZO1 (PB2, PB3), and occludin (PB1, PB2). Taken together, B. subtilis supplementation altered intestinal immune activity and influenced gut barrier integrity through increased tight junction gene expression.

Autologous adipose tissue-derived stem cells for the treatment of complex perianal fistulas not associated with Crohn's disease: a phase II clinical trial for safety and efficacy

PURPOSE

Injection of adipose tissue-derived stem cells (ASCs) is a novel method for the treatment of complex perianal fistulas. We aimed to evaluate the safety and efficacy of ASCs in the treatment of complex anal fistulas not associated with Crohn's disease.

METHODS

A phase II clinical trial was performed comparing two different doses of ASCs (group 1: 1 × 10⁷ cells/mL and group 2: 2 × 10⁷ cells/mL). Eligible patients were administered an amount of ASCs proportional to the length of the fistula by injection into the submucosal layer surrounding the internal opening and inside of the fistula tract. ASCs at twice the initial concentration were administered if complete closure was not achieved within 8 weeks. The efficacy endpoint was the complete closure of fistulas 8 weeks after injection. Patients demonstrating complete closure at week 8 were subjected to follow-up for 6 months.

RESULTS

Fifteen patients were injected with ASCs; thirteen completed the study. Complete closure was observed in 69.2% (9/13) of patients at 8 weeks. Three of five patients in group 1, and six of eight in group 2 displayed complete closure; no significant differences were observed between the groups. Six of nine patients who showed complete closure participated in additional follow-up; five (83.3%) showed persistent response at 6 months. No grade 3 or 4 adverse events (AEs) were observed; observed AEs were not related to ASC treatment.

CONCLUSION

ASCs might be a good option for the treatment of complex perianal fistulas are not healed by conventional operative procedures.

Selective inhibition of histone deacetylase 2 induces p53-dependent survivin downregulation through MDM2 proteasomal degradation

In the present study, we found that selective inhibition of histone deacetylase 2 (HDAC2) with small inhibitory RNA (siRNA) induced survivin downregulation in a p53-dependent manner. Interestingly, suberoylanilide hydroxamic acid (SAHA) or knockdown of HDAC2 induced downregulation of Mdm2, a negative regulator of p53, at the protein level. SAHA and/or HDAC2 siRNA increased Mdm2 ubiquitination, and MG132, an inhibitor of proteosome function, prevented HDAC2 inhibition-induced degradation of Mdm2. Clinically, the mRNA levels of HDAC2 and survivin were prominently overexpressed in lung cancer patients compared to normal lung tissues. Silencing of HDAC2 enhanced the cell death caused by ionizing radiation in lung cancer cells. Collectively, our results indicate that selective inhibition of HDAC2 causes survivin downregulation through activation of p53, which is mediated by downregulation of Mdm2. They further suggest that HDAC2 may exert a dominant effect on lung cancer cell survival by sustaining Mdm2-survivin levels.

Electro-hyperthermia up-regulates tumour suppressor Septin 4 to induce apoptotic cell death in hepatocellular carcinoma

PURPOSE

Modulated electro-hyperthermia (mEHT) has been shown to be effective against various types of human tumours, including hepatocellular carcinoma (HCC). Here we aimed to investigate the molecular mechanism underlying the cytotoxic effects of mEHT to HCC cells.

MATERIALS AND METHODS

Human liver cancer cell lines, Huh7 and HepG2, were treated with mEHT (42 °C/60 min) three times at 2-day intervals. Growth inhibition and apoptotic induction were evaluated using MTS, microscopic analysis, a clonogenic assay, annexin V/PI staining and a ccK18 ELISA. Global changes in gene expression were examined using RNA sequencing to obtain insights into molecular changes in response to mEHT. For in vivo evaluation of mEHT we used HepG2 HCC xenografts grown in nude mice.

RESULTS

mEHT suppressed HCC cell proliferation and long-term colony formation through induction of apoptosis. The growth inhibitory effects are induced through a subset of molecular changes. Notably the expression level of septin 4 (SEPT4) (involved in pro-apoptotic activity and growth suppression) was up-regulated, whereas a key regulator of invasiveness G-Protein coupled receptor 64 (GPR64) was repressed. Subsequent Western blotting confirmed that the common increase in tumour suppressor SEPT4 in both Huh7 and HepG2 cells is accompanied by the restoration of cyclin-dependent kinase (CDK) inhibitor p21 and decrease in pro-caspase 7 and pro-caspase 3, thereby accelerating apoptotic signalling in HCC cells. Additionally, mEHT significantly inhibited the growth of human HCC xenografts in nude mice.

CONCLUSIONS

These findings suggest that apoptotic cell death induced by mEHT is mediated by the up-regulation of tumour suppressor SEPT4 in human HCC cells.

Melatonin enhances arsenic trioxide-induced cell death via sustained upregulation of Redd1 expression in breast cancer cells

Melatonin is implicated in various physiological functions, including anticancer activity. However, the mechanism(s) of its anticancer activity is not well understood. In the present study, we investigated the combined effects of melatonin and arsenic trioxide (ATO) on cell death in human breast cancer cells. Melatonin enhanced the ATO-induced apoptotic cell death via changes in the protein levels of Survivin, Bcl-2, and Bax, thus affecting cytochrome c release from the mitochondria to the cytosol. Interestingly, we found that the cell death induced by co-treatment with melatonin and ATO was mediated by sustained upregulation of Redd1, which was associated with increased production of reactive oxygen species (ROS). Combined treatment with melatonin and ATO induced the phosphorylation of JNK and p38 MAP kinase downstream from Redd1 expression. Rapamycin and S6K1 siRNA enhanced, while activation of mTORC1 by transfection with TSC2 siRNA suppressed the cell death induced by melatonin and ATO treatment. Taken together, our findings suggest that melatonin enhances ATO-induced apoptotic cell death via sustained upregulation of Redd1 expression and inhibition of mTORC1 upstream of the activation of the p38/JNK pathways in human breast cancer cells.

Electro-hyperthermia inhibits glioma tumorigenicity through the induction of E2F1-mediated apoptosis

PURPOSE

Modulated electro-hyperthermia (mEHT), also known as oncothermia, shows remarkable treatment efficacies for various types of tumours, including glioma. The aim of the present study was to investigate the molecular mechanism underlying phenotypic changes in oncothermic cancer cells.

MATERIALS AND METHODS

U87-MG and A172 human glioma cells were exposed to mEHT (42 °C/60 min) three times with a 2-day interval and subsequently tested for growth inhibition using MTS, FACS and microscopic analysis. To obtain insights into the molecular changes in response to mEHT, global changes in gene expression were examined using RNA sequencing. For in vivo evaluation of mEHT, we used U87-MG glioma xenografts grown in nude mice.

RESULTS

mEHT inhibited glioma cell growth through the strong induction of apoptosis. The transcriptomic analysis of differential gene expression under mEHT showed that the anti-proliferative effects were induced through a subset of molecular alterations, including the up-regulation of E2F1 and CPSF2 and the down-regulation of ADAR and PSAT1. Subsequent Western blotting revealed that mEHT increased the levels of E2F1 and p53 and decreased the level of PARP-1, accelerating apoptotic signalling in glioma cells. mEHT significantly suppressed the growth of human glioma xenografts in nude mice. We also observed that mEHT dramatically reduced the portion of CD133(+) glioma stem cell population and suppressed cancer cell migration and sphere formation.

CONCLUSIONS

These findings suggest that mEHT suppresses glioma cell proliferation and mobility through the induction of E2F1-mediated apoptosis and might be an effective treatment for eradicating brain tumours.

Clonal evolution revealed by whole genome sequencing in a case of primary myelofibrosis transformed to secondary acute myeloid leukemia

Clonal architecture in myeloproliferative neoplasms (MPNs) is poorly understood. Here we report genomic analyses of a patient with primary myelofibrosis (PMF) transformed to secondary acute myeloid leukemia (sAML). Whole genome sequencing (WGS) was performed on PMF and sAML diagnosis samples, with skin included as a germline surrogate. Deep sequencing validation was performed on the WGS samples and an additional sample obtained during sAML remission/relapsed PMF. Clustering analysis of 649 validated somatic single-nucleotide variants revealed four distinct clonal groups, each including putative driver mutations. The first group (including JAK2 and U2AF1), representing the founding clone, included mutations with high frequency at all three disease stages. The second clonal group (including MYB) was present only in PMF, suggesting the presence of a clone that was dispensable for transformation. The third group (including ASXL1) contained mutations with low frequency in PMF and high frequency in subsequent samples, indicating evolution of the dominant clone with disease progression. The fourth clonal group (including IDH1 and RUNX1) was acquired at sAML transformation and was predominantly absent at sAML remission/relapsed PMF. Taken together, these findings illustrate the complex clonal dynamics associated with disease evolution in MPNs and sAML.

Effects of onion extracts on growth performance, carcass characteristics and blood profiles of white mini broilers

This experiment was carried out to investigate effects of onion extract on growth performance, meat quality and blood profiles of White mini broilers. Total of 600 one-d-old male White mini broiler chicks were divided into four groups and fed control diets (non-medicated commercial diet or antibiotics medicated) or experimental diets (non-medicated diets containing 0.3% or 0.5% onion extract) for 5 wks. The final body weight (BW) and weight gain of the group fed non-medicated control diet were lower than those of medicated control group (p<0.01). The chicks fed diet with 0.3% or 0.5% onion extract showed a similar BW to that of medicated control group. The relative weight of various organs, such as liver, spleen, bursa of Fabricius, abdominal fat, and the activities of serum enzymes were not affected by dietary treatments. There were no significant differences in meat color among groups. Whereas, groups fed diets containing onion extract had slightly lower cooking loss and higher shear force value, but not significantly. The concentrations of serum free cholesterol and triacylglycerol in groups fed diet containing onion extract were significantly decreased compared with those of controls (p<0.01). In conclusion, the onion extracts exerted a growth-promoting effect when added in White mini broiler diets, reflecting potential alternative substances to replace antibiotics.

Effects of Dietary Fermented Chlorella vulgaris (CBT(®)) on Growth Performance, Relative Organ Weights, Cecal Microflora, Tibia Bone Characteristics, and Meat Qualities in Pekin Ducks

Fermented Chlorella vulgaris was examined for its effects on growth performance, cecal microflora, tibia bone strength, and meat qualities in commercial Pekin ducks. A total of three hundred, day-old male Pekin ducks were divided into three groups with five replicates (n = 20 ducklings per replicate) and offered diets supplemented with commercial fermented C. vulgaris (CBT(®)) at the level of 0, 1,000 or 2,000 mg/kg, respectively for 6 wks. The final body weight was linearly (p = 0.001) increased as the addition of fermented C. vulgaris into diets increased. Similarly, dietary C. vulgaris linearly increased body weight gain (p = 0.001) and feed intake (p = 0.001) especially at the later days of the feeding trial. However, there was no C. vulgaris effect on feed efficiency. Relative weights of liver were significantly lowered by dietary fermented C. vulgaris (linear effect at p = 0.044). Dietary fermented C. vulgaris did not affect total microbes, lactic acid bacteria, and coliforms in cecal contents. Finally, meat quality parameters such as meat color (i.e., yellowness), shear force, pH, or water holding capacity were altered by adding fermented C. vulgaris into the diet. In our knowledge, this is the first report to show that dietary fermented C. vulgaris enhanced meat qualities of duck meats. In conclusion, our study indicates that dietary fermented C. vulgaris exerted benefits on productivity and can be employed as a novel, nutrition-based strategy to produce value-added duck meats.

Evaluation of dietary multiple enzyme preparation (natuzyme) in laying hens

The current experiment was designed to evaluate the efficacy of adding the multi-enzyme mixture (Natuzyme) into layers' diets with different levels of energy and available phosphorus in relation to laying performance, egg qualities, blood cholesterol level, microflora and intestinal viscosity. Two hundred and fifty 43-wk-old Hy-Line commercial layers were divided into five groups with five replicates per group (10 birds per replicate) and fed one of five experimental diets. A corn and soybean meal-based control diet was formulated and used as a control diet. Two experimental control diets were formulated to reduce energy and crude protein contents (rE) or energy, crude protein and phosphorus contents (rEP). In addition, Natuzyme was added into either rE (rE-Natu500) or rEP (rEP-Natu500) diet to reach a concentration of 500 mg per kg of diet. The experiment lasted 8 weeks. There were no significant differences in feed intake, egg production, egg weight, egg qualities such as eggshell color or Haugh unit, total cholesterol, relative organ weights and cecal microflora profiles between any dietary treatments. Natu500 supplementation into the rE diet, but not rEP diet significantly increased egg mass and eggshell qualities such as strength and thickness, but it decreased cecal ammonia concentration and intestinal viscosity in laying hens. In conclusion, the present study shows that adding multiple enzyme preparation could improve performance of laying hens fed energy and protein restricted diets.

Growth performance and carcass characteristics of korean native ducks fed diets with varying levels of limiting amino acids

There are multiple experiments conducted with male Korean native ducks (KND) to evaluate the optimal levels of limiting amino acids (AA). In Exp. 1, a total of 450 one-d-old male KNDs were divided into five groups with six replicates and fed experimental diets with varying levels of lysine, total sulfur amino acids (TSAA) and threonine (T1, 0.90/0.74/0.70%; T2, 1.00/0.82/0.77%; T3, 1.10/0.90/0.85%; T4, 1.20/0.98/0.93%; T5, 1.30/1.07/1.01%) to 21 d of age. In Exp. 2, one-d-old male KND were received and fed commercial starter diet from hatching to 21 d of age, and then divided into five groups with six replicates and fed one of five diets varying levels of lysine, TSAA, and threonine (T1, 0.73/0.62/0.54%; T2, 0.80/0.68/0.60%; T3, 0.87/0.74/0.65%; T4, 0.94/0.80/0.70%; T5, 1.01/0.86/0.75%) during 22 to 56 d of age, respectively. The BW gain was linearly increased as dietary limiting AA levels increased to 1.20% lysine, 0.98% TSAA and 0.93% threonine. There were no significant differences in feed intake, gain:feed and uniformity among groups. In Exp. 2, the BW gain and gain:feed were not affected by dietary limiting AA levels. There were no significant differences in carcass characteristics and meat quality among groups. The growth performance and carcass characteristics did not show the significant response to increasing dietary limiting AA levels in KND during 22 to 56 d of age. In conclusion, the levels of lysine, TSAA and threonine necessary to maximize growth for starter phase were at least 1.20%, 0.98%, and 0.93%, respectively. On the other hands, KND require relatively low levels of limiting AA for late growth and carcass yield. The dietary levels of 0.73% lysine, 0.62% TSAA and 0.54% threonine appear to be adequate during growing phase.

Nutritional and Hormonal Induction of Fatty Liver Syndrome and Effects of Dietary Lipotropic Factors in Egg-type Male Chicks

This experiment was conducted with male chicks to investigate the influence of hormones and nutrients on the development of fatty liver syndrome (FLS) as well as the effects of dietary lipotropic factors on hepatic fat accumulation and lipogenic enzyme gene expression. A total of two-hundred sixteen 4-wk-old Hy-Line male chicks were divided into six groups and fed an experimental diet (T1, low-energy diet with low levels of lipotropic factors; T2, high-energy diet with low levels of lipotropic factors; T3 and T5, low-energy diet with high levels of lipotropic factors; T4 and T6, high-energy diet with high levels of lipotropic factors) for six weeks. The chicks in T5 and T6 groups were treated with intramuscular injections of estradiol benzoate for three days prior to biopsy and clinical analysis of FLS. Chicks treated with estrogen had significantly greater liver weights than untreated chicks. The abdominal fat contents were increased in chicks consuming high-energy diets as compared to those consuming low-energy diets. Treatment with estrogen significantly increased the concentrations of serum cholesterol, triacylglycerol and phospholipid (p<0.05). The hepatic triacylglycerol levels were tenfold higher in the estrogen treated chicks than in the untreated chicks. There were no significant differences in malondialdehyde levels between the treatment groups. Estrogen treatment dramatically increased the levels of fatty acid synthetase, acetyl-CoA carboxylase and ApoB mRNA. The results indicated that treatment with exogenous estrogen in growing male chicks induced hepatic fat accumulation, which might be partially due to increased lipogenic enzyme gene expression.

Comparison of growth performance, carcass characteristics and meat quality of korean local chickens and silky fowl

This study was conducted to compare growth performance, carcass characteristics and meat quality of 4 breeds of local chicken. A total of 480 1-d-old chicks were distributed to 16 pens, with 4 treatments of breed, 4 replicates and 30 chicks per pen. Three Korean local breeds of white-mini broiler, Hanhyup-3-ho, and Woorimatdag, and a breed of silky fowl were raised under identical rearing and feeding conditions for 31-d, 37-d, 36-d, and 59-d, respectively. The BW and feed consumption on a pen basis were weekly measured for all pens, and ADFI, ADG and gain:feed were calculated for each pen. The ADFI and ADG of 3 breeds of Korean local chicken were greater than those of silky fowl (p<0.05). Within the Korean local breeds, ADFI of white-mini broiler was the highest (p<0.05), and ADG of Hanhyup-3-ho and white-mini broiler was the highest (p<0.05). Gain:feed of silky fowl was less than that of the 3 breeds of Korean local chicken. The carcass and breast yield of white-mini broiler were the greater than those of other breeds (p<0.05). The breast meat color (CIE L*, a*, and b*) of 3 breeds of Korean local chicken were higher than that of silky fowl (p<0.05). The breast meat of Hanhyup-3-ho had greater cooking loss (p<0.05), whereas water holding capacity and pH were less than those of other breeds (p<0.05). The color score of 3 breeds of Korean local chicken was higher than that of silky fowl (p<0.05). Woorimatdag had a higher score on tenderness (p<0.05), whereas flavor score was less than that of other breeds (p<0.05). In conclusion, 4 local breeds of chicken have some unique features and seem to have more advantages, and this information can help consumers who prefer healthy and premium chicken meat.

Adjuvant chemotherapy for gastric cancer: a randomised phase 3 trial of mitomycin-C plus either short-term doxifluridine or long-term doxifluridine plus cisplatin after curative D2 gastrectomy (AMC0201)

BACKGROUND

This phase 3 study evaluated the efficacy of new adjuvant chemotherapy (MFP), which intensified the mitomycin-C (MMC) plus short-term doxifluridine (Mf) for gastric cancer.

PATIENTS AND METHODS

A total of 855 patients (424 in Mf, 431 in MFP) with pathological stage II-IV (M0) gastric cancer after D2 gastrectomy were randomly assigned to receive either Mf (MMC 20 mg m(-2), followed by oral doxifluridine 460-600 mg m(-2) per day for 3 months) or MFP (MMC 20 mg m(-2), followed by oral doxifluridine 460-600 mg m(-2) per day for 12 months with 6 monthly infusions of 60 mg m(-2) of cisplatin) chemotherapy.

RESULTS

With a median follow-up of 6.6 years, there was no difference between the two groups in recurrence-free survival (RFS) (5-year RFS 61.1% in Mf and 57.9% in MFP; hazard ratio 1.10 (95% CI 0.89-1.35); P=0.39) and overall survival (OS) (5-year OS 66.5% in Mf and 65.0% in MFP; hazard ratio 1.11 (95% CI 0.89-1.39); P=0.33).

CONCLUSION

Intensification of Mf adjuvant chemotherapy by prolonging the duration of oral fluoropyrimidine and adding cisplatin was safe but not effective to improve the survivals in curatively resected gastric cancer patients.

Effects of dietary persimmon peel and its ethanol extract on the production performance and liver lipids in the late stage of egg production in laying hens

The purpose of this study was to investigate the dietary effects of persimmon peel (PP) and PP ethanol extract (PPE) on egg production, egg quality, and liver lipids in the late stage of egg production in laying hens. One hundred and twenty 50-wk-old Hy-Line Brown layers (n = 120) were fed different diets. Four replicate groups of 6 hens each were randomly assigned to 5 dietary treatments. The 5 dietary treatments were as follows: i) CON, basal diet; ii) PP 0.15, CON+0.15% PP (0.035% tannin); iii) PP 0.5, CON +0.5% PP (0.117% tannin); iv) PPE 0.075, CON+0.075% PPE (0.03% tannin); and v) PPE 0.25, CON+0.25% PPE (0.11% tannin). The total tannin concentration of PPE was higher (p<0.05) than that of PP. Egg production in the PP 0.5 group was higher than in the other groups. Egg production and mass of hens in the PPE 0.25 group showed a greater decrease than that in the other groups (p<0.05). Eggshell color in the PP 0.15, PP 0.5, and PPE 0.075 groups was lighter than that of the control group (p<0.05). The Haugh unit for the groups that were fed PP and PPE were significantly higher than that in the other groups after 7 d of storage (p<0.05). Therefore, PP seems an effective feed additive for improving the production performance and egg quality in late stage laying hens.

Suitability of endoscopic submucosal dissection for treatment of submucosal gastric cancers

BACKGROUND

Endoscopic submucosal dissection (ESD) is not considered appropriate for all submucosal cancers owing to the risk of lymph node metastasis and difficulty estimating the deep margin status. This study aimed to determine predictive factors for lymph node metastases in submucosal cancer and to explore in which patients ESD might be feasible.

METHODS

Details of patients who had curative gastrectomy for submucosal gastric cancer at Asan Medical Centre from 2007 to 2011 were reviewed retrospectively to determine the relationship between lymph node metastasis and clinicopathological characteristics, including age, sex, tumour location, size, gross appearance, depth of invasion, histological type/differentiation, presence of lymphovascular/perineural invasion, and immunohistochemical staining results for p53, human epidermal growth factor receptor (HER) 1 and HER2.

RESULTS

A total of 1773 patients were analysed. The presence of lymphovascular invasion was related most strongly to lymph node metastasis. Multivariable analysis revealed that depth of invasion, tumour size, differentiation, gross appearance and perineural invasion were also related. Metastatic lymph nodes were found in four of 105 patients who met the classical criteria for ESD; all showed a moderately differentiated histological appearance. No lymph node metastases were observed in well differentiated SM1 tumours of any size (infiltration into upper third of submucosa), or in well differentiated SM2 (infiltration into middle third of submucosa) tumours of 2 cm or less without lymphovascular invasion.

CONCLUSION

Patients with well differentiated SM1 cancer of any size and those with well differentiated SM2 cancer of 2 cm or less without lymphovascular invasion may be suitable candidates for ESD.

Brain metastases from colorectal cancer: the role of surgical resection in selected patients

AIM

Brain metastasis is infrequent in colorectal cancer patients, and the prognosis is poor. In this retrospective study survival and prognostic factors were determined in patients with brain metastasis from colorectal cancer.

METHOD

Between 1997 and 2006, 39 patients with brain metastasis from colorectal cancer who survived more than 1 month were identified. Data were collected with regard to patient characteristics, location and stage of the primary tumour, extent and location of metastatic disease, and treatment modalities used.

RESULTS

Most (79.5%) patients had pulmonary metastases before brain metastasis, and the brain was the site of solitary metastasis in only one patient. The most frequent symptom was weakness [18 (43.6%) patients]. Overall median survival was 5.0 months and the 1- and 2-year survival rates were 21.8 and 9.1%, respectively. Univariate analysis revealed uncontrolled extracranial metastases (P = 0.019), multiple brain lesions (P = 0.026), bilateral brain metastases (P = 0.032) and serum carcinoembryonic antigen levels greater than 5 ng/ml (P = 0.008) to be poor prognostic factors. The median survival after the diagnosis of brain metastasis was significantly longer in patients who underwent surgical resection (15.2 ± 8.0 months) than in those treated by other modalities (P = 0.001). Treatment modality was the only independent prognostic factor for overall survival in patients with brain metastases from colorectal cancers (P = 0.015).

CONCLUSION

Aggressive surgical resection in selected patients with brain metastases from colorectal cancer may prolong survival, even in the presence of extracranial metastatic lesions.

Increased immunoreactivity of membrane type-1 matrix metalloproteinase (MT1-MMP) and β-catenin in high-risk basal cell carcinoma

BACKGROUND

Although various immunohistological markers have been investigated to assess the aggressive characteristics of basal cell carcinoma (BCC), the role of membrane type-1 matrix metalloproteinase (MT1-MMP) has not been well established.

OBJECTIVES

To clarify the precise role of MT1-MMP in BCC, MT1-MMP expression was studied in various histological subtypes of BCC.

MATERIALS AND METHODS

High-risk subtypes of BCC were compared by assessing the expression of β-catenin and MT1-MMP. The tissue microarray technique was used for immunohistochemical staining. Fifty-eight samples were divided into six subtypes (10 nodular, 12 mixed, nine infiltrative, eight morphoeiform, 10 micro-nodular and nine basosquamous). Overall, the 10 nodular BCC samples were classified as low-risk BCC and the remaining 48 samples were classified as high-risk BCCs.

RESULTS

β-Catenin immunoreactivity was increased in the high-risk BCCs compared with the low-risk (nodular) BCC (P < 0·001). Nuclear β-catenin immunoreactivity was increased at the invading front of mixed BCC tumour islands compared with the upper portion of the lesion (P < 0·01). For the mixed BCC (P < 0·01), infiltrative BCC (P < 0·001), morphoeiform BCC (P < 0·001), micronodular BCC (P < 0·001) and basosquamous (P < 0·001) carcinoma, β-catenin immunoreactivity was increased at the invading front compared with nodular BCC. MT1-MMP immunoreactivity was increased in the high-risk BCCs compared with the low-risk (nodular) BCC (P < 0·01). The membranous MT1-MMP immunoreactivity was increased at the invading front of mixed BCC tumour islands compared with the upper portion of the lesions (P < 0·01). For the mixed (P < 0·01), infiltrative (P < 0·05), morphoeiform (P < 0·05), micronodular (P > 0·05) and basosquamous (P < 0·05) BCC, MT1-MMP immunoreactivity was also increased at the invading front compared with nodular BCC.

CONCLUSIONS

The results of this study suggest that MT1-MMP might be a novel marker for high-risk BCC. In addition, expression of both β-catenin and MT1-MMP was increased in high-risk BCC tumour cells, indicating that these two proteins may play an important role in locally invasive and highly destructive growth behaviour of high-risk BCCs.

The Dietary Effects of Fermented Chlorella vulgaris (CBT(®)) on Production Performance, Liver Lipids and Intestinal Microflora in Laying Hens

Fermented Chlorella vulgaris CBT^® was evaluated for its effects on egg production, egg quality, liver lipids and intestinal microflora in laying hens. One hundred and eight Hy-line Brown layers (n = 108), 80 wk of age, were fed a basal diet supplemented with CBT^® at the level of 0, 1,000 or 2,000 mg/kg, respectively for 42 d. Egg production was measured daily and egg quality was measured every two weeks. Five eggs from each replicate were collected randomly to determine egg quality. Egg production increased linearly with increasing levels of CBT^® supplementation (p<0.05), although there was no significant effect of treatment on feed intake. Egg yolk color (p<0.001) and Haugh unit (p<0.01) improved linearly with increasing dietary CBT^®. Hepatic triacylglycerol level was linearly decreased with increasing dietary CBT^® (p<0.05). The supplemental CBT^® resulted in linear (p<0.001) and quadratic (p<0.01) response in population of cecal lactic acid bacteria. In conclusion, fermented Chlorella vulgaris supplemented to laying hen diets improved egg production, egg yolk color, Haugh unit and positively affected the contents of hepatic triacylglycerol and the profiles of cecal microflora.

Association between interleukin-4R and TGF-β1 gene polymorphisms and the risk of colorectal cancer in a Korean population

AIM

Colorectal cancer is associated with inflammatory bowel disease. The mechanisms of how different genetic make-ups of cytokines might influence the individual susceptibility to develop particular types of tumours are still unknown. The authors analysed the association between genetic polymorphisms in cytokine/cytokine receptor genes and the risk of colorectal cancer in a Korean population.

METHOD

The authors assessed polymorphisms of the interleukin: IL-1, IL-1R, IL-2, IL-4, IL-4R, IL-10, transforming growth factor (TGF)-β1, IFN-γ genes in Korean patients with colorectal cancer (n = 170) and in a normal healthy control group (n = 130) to investigate the association between theses cytokine gene polymorphisms and the risk of colorectal cancer.

RESULTS

The IL-4R 1902*T allele was found to be associated with an increased risk of colon cancer (P < 0.01, OR = 2.0) and rectal cancer (P < 0.05, OR = 1.8). The IL-4R 1902*C allele was associated with a decreased risk of both colon cancer (P < 0.01, OR = 0.51) and rectal cancer (P < 0.05, OR = 0.5). The TFG-β1 10*T allele was found to be associated with an increased risk of colon cancer (P < 0.00, OR = 2.3) and the TFG-β1 10*C allele with a decreased risk of colon cancer (P < 0.00, OR = 0.43).

CONCLUSION

These results suggest that the genetic polymorphisms of IL-4R and TGF-β1 are associated with the risk of colorectal cancer in a Korean population.

Development of KSTAR Thomson scattering system

To measure the electron temperature (T(e)) and electron density (n(e)) profiles in the Korean Superconducting Tokamak Advanced Research (KSTAR) device for the KSTAR third campaign (September 2010), we designed and installed a Thomson scattering system. The KSTAR Thomson scattering system is designed as a tangential Thomson scattering system and utilizes the N-, L-, and B-ports. The N-port is designed for the collection optics with a cassette system, the L-port is the laser input port, and the B-port is the location of the beam dump. In this paper, we will describe the final design of the KSTAR Thomson scattering system.

Diagnostics for first plasma and development plan on KSTAR

The first plasma with target values of the plasma current and the pulse duration was finally achieved on June 13, 2008 in the Korea Superconducting Tokamak Advanced Research (KSTAR). The diagnostic systems played an important role in achieving successful first plasma operation for the KSTAR tokamak. The employed plasma diagnostic systems for the KSTAR first plasma including the magnetic diagnostics, millimeter-wave interferometer, inspection illuminator, H(alpha), visible spectrometer, filterscope, and electron cyclotron emission (ECE) radiometer have provided the main plasma parameters, which are essential for the plasma generation, control, and physics understanding. Improvements to the first diagnostic systems and additional diagnostics including an x-ray imaging crystal spectrometer, reflectometer, ECE radiometer, resistive bolometer, and soft x-ray array are scheduled to be added for the next KSTAR experimental campaign in 2009.

A comparative study on the short-term clinicopathologic outcomes of laparoscopic surgery versus conventional open surgery for transverse colon cancer

BACKGROUND

The long-term oncologic stability of laparoscopic surgery for colon cancer was established, and laparoscopic surgery was accepted as an alternative to conventional open surgery for colon cancer. However, transverse colon cancer was excluded from the majority of the previous prospective studies. As a result, debate on laparoscopic surgery for transverse colon cancer continues. This study aimed to compare the clinicopathologic outcome of laparoscopic surgery with that of conventional open surgery for transverse colon cancer.

METHODS

From August 2004 to December 2007, 106 cases of transverse colon cancer were managed by resection at our institution, and 89 of these cases were included in this study. Age, sex, body mass index (BMI), operation time, blood loss, time to first flatus, time to start of diet, hospital stay, complications, tumor size, distal resection margin, proximal resection margin, and number of nodes harvested were compared between the two groups.

RESULTS

No significant differences were found between the laparoscopic and conventional groups in terms of age, sex, BMI, operation time, or hospital stay. The mean blood loss during the operations was significantly less in the laparoscopic group (113.8 +/- 128.9 ml) than in the conventional group (278.8 +/- 268.7 ml; p < 0.05). Moreover, the time to the first flatus was shorter (2.8 +/- 0.9 days vs. 4.4 +/- 2.0 days; p < 0.00) and the diet was started earlier (3.9 +/- 1.7 days vs. 5.4 +/- 1.9 days; p < 0.00) in the laparoscopic group. No intergroup differences in tumor size, proximal resection margin, or number of lymph nodes were observed. The mean distal resection margin was longer in the laparoscopic group (12.5 +/- 4.1 cm vs. 9.2 +/- 6.2 cm; p < 0.05).

CONCLUSION

Laparoscopic and conventional open surgeries were found to have similar clinical outcomes in transverse colon cancer, and the oncologic quality of laparoscopic surgery was found to be acceptable compared with conventional open surgery.

Maintenance of the viral episome is essential for the cell survival of an Epstein-Barr virus positive gastric carcinoma cell line

While Epstein Barr virus (EBV) is associated with about 10% of gastric carcinomas worldwide, the role of the virus in the tumorigenesis of EBV-associated gastric carcinoma (EBVaGC) is unclear. Previously, we reported that a gastric cancer cell line, SNU-719, that is naturally infected with EBV closely resembles EBVaGC. Here, we attempted to eliminate the EBV genome from SNU-719 cells to ascertain the influence of EBV in EBVaGC. Southern blotting and fluorescence in situ hybridization (FISH) showed that EBV genomes were maintained as episomes in SNU-719 cells. To remove EBV episomes, SNU-719 cells were first cultured in a hydroxyurea (HU)-containing medium for up to 6 months. Real-time polymerase chain reaction and FISH results revealed no evidence of HU-mediated EBV genome reduction, although cell growth was reduced by acute HU treatment in dose- and time-dependent manners. Two small interfering RNAs against Epstein Barr nuclear antigen 1 (EBNA1) abrogated over 90% of the ectopic EBNA1 expression in HeLa cells, but only 40% of endogenous EBNA1 expression in SNU-719 cells. Together, our data suggest that maintenance of latent EBV infection is essential for the viability of EBVaGC cells, avoiding elimination of EBV episomes from the cells.

Surgical and pathological outcomes of laparoscopic surgery for transverse colon cancer

PURPOSE

Several multi-institutional prospective randomized trials have demonstrated short-term benefits using laparoscopy. Now the laparoscopic approach is accepted as an alternative to open surgery for colon cancer. However, in prior trials, the transverse colon was excluded. Therefore, it has not been determined whether laparoscopy can be used in the setting of transverse colon cancer. This study evaluated the peri-operative clinical outcomes and oncological quality by pathologic outcomes of laparoscopic surgery for transverse colon cancer.

MATERIALS AND METHODS

Analysis of the medical records of patients who underwent laparoscopic colorectal resection from August 2004 to November 2007 was made. Computed tomography, barium enema, and colonoscopy were performed to localize the tumor preoperatively. Extended right hemicolectomy, transverse colectomy, and extended left hemicolectomy were performed for transverse colon cancer. Surgical outcomes and pathologic outcomes were compared between transverse colon cancer (TCC) and other site colon cancer (OSCC).

RESULTS

Of the 312 colorectal cancer patients, 94 patients underwent laparoscopic surgery for OSCC, and 34 patients underwent laparoscopic surgery for TCC. Patients with TCC were similar to patients with OSCC in age, gender, body mass index, operating time, blood loss, time to pass flatus, start of diet, hospital stay, tumor size, distal resection margin, proximal resection margin, number of lymph nodes, and radial margin. One case in TCC and three cases in OSCC were converted to open surgery.

CONCLUSIONS

Laparoscopic surgery for transverse colon cancer and OSCC had similar peri-operative clinical and acceptable pathological outcomes.

Induction of efficient differentiation and survival of porcine neonatal pancreatic cell clusters using an EBV-based plasmid expressing HGF

Porcine neonatal pancreatic cell clusters (NPCCs) have been actively studied as a source of pancreatic stem cell transplantation for the treatment of diabetes. In this study, the hepatocyte growth factor (HGF) gene was cloned in an Epstein-Barr virus (EBV)-based plasmid vector (pEBVHGF) and the effects of the HGF expression on the survival and differentiation of NPCCs were analysed. For comparison, pHGF was constructed by deleting EBNA-1 and OriP from pEBVHGF. The expression of HGF, as measured by ELISA, lasted longer when pEBVHGF was used than when pHGF was used. C-Met phosphorylation co-related with the expression of HGF in the transfected NPCCs. Immunocytochemistry experiments showed that NPCCs showed a higher and longer expression of insulin when they were transfected with pEBVHGF than with pHGF. Moreover, a greater number of NPCCs survived for a longer period after they were transfected with pEBVHGF than when they were transfected with pHGF. Taken together, these results indicate that transfecting NPCCs with the HGF gene using an EBV-based plasmid is a more effective method of inducing differentiation to beta cells and enhancing survival than using a conventional plasmid. Therefore, it may be possible to use EBV-based plasmids to modify pancreatic stem cells for xenotransplantation.

Adjuvant chemotherapy with 5-fluorouracil, doxorubicin and mitomycin-C (FAM) for 6 months after curative resection of gastric carcinoma

AIM

This study aimed to evaluate the efficacy and safety of 5-fluorouracil (5-FU), doxorubicin and mitomycin-C (FAM) adjuvant chemotherapy in patients who had undergone curative resection of gastric carcinoma.

METHODS

From Nov 1999 to Jan 2002, 291 consecutive patients with stage IB-IIIB gastric adenocarcinoma were given FAM adjuvant chemotherapy. Chemotherapy comprised intravenous 5-FU 600 mg/m(2) (days 1, 8, 29 and 36), doxorubicin 30 mg/m(2) (days 1 and 29) and mitomycin-C 10 mg/m(2) (day 1), every 8 weeks for 6 months.

RESULTS

The median follow-up time was 60.6 months, 92 patients died, and 93 patients had recurrent disease. The 5-year overall survival (OS) rates were 85.9% for stage IB, 72.1% for stage II, 58.0% for stage IIIA, and 48.2% for stage IIIB (p=0.002). The 5-year relapse-free survival (RFS) rates were 85.2% for stage IB, 71.2% for stage II, 53.3% for stage IIIA, and 39.2% for stage IIIB (p<0.001). A total of 769 cycles of chemotherapy were delivered, and 15 patients experienced grade 3 or higher leukopenia. The most common grade 3 or higher non-hematologic toxicity was nausea/vomiting (11 patients), followed by stomatitis (3 patients).

CONCLUSIONS

Adjuvant chemotherapy with FAM for 6 months for gastric carcinoma indicated comparable RFS and OS with an acceptable toxicity profile.

Establishment and characterization of an in vivo model for Epstein–Barr virus positive gastric carcinoma

Research regarding the role of the Epstein-Barr virus (EBV) in gastric carcinogenesis has been hampered by the absence of a suitable model system. SNU-719 is a gastric carcinoma cell line naturally infected with EBV. This cell line developed tumors in nude mice approximately 40-56 days after inoculation. SNU-719 also showed low serum dependency and anchorage independent growth in vitro. The developed tumors expressed EBERs, EBNA1, and LMP2A but not other EBV latent genes. Additionally, Qp was active and either mono- or bi-clonal EBV genome was observed in the tumor tissues. Because the developed tumors retained characteristics of EBV-associated gastric cancer, this cell line could serve as a useful in vivo system to investigate the tumorigenesis mechanism and treatment methods for this type of tumor.

Expression of viral microRNAs in Epstein-Barr virus-associated gastric carcinoma

Epstein-Barr virus (EBV) is associated with about 6 to 16% of gastric carcinoma cases worldwide. Expression of the EBV microRNAs (miRNAs) was observed in B cells and nasopharyngeal carcinoma cells infected with EBV. However, it is not clear if the EBV miRNAs are expressed in EBV-associated gastric carcinomas (EBVaGCs). We found that BART miRNAs but not BHRF1 miRNAs were expressed in EBV-infected gastric carcinoma cell lines and the tumor tissues from patients as well as the animal model. The expression of viral miRNAs in EBVaGCs suggests that these EBV miRNAs may play important roles in the tumorigenesis of EBVaGCs.

Mechanism of prolonged gene expression by Epstein-Barr virus-based plasmid in porcine cells

BACKGROUND

We previously showed that an Epstein-Barr virus (EBV)-based plasmid, pEBVGFP, exerts prolonged gene expression in porcine neonatal pancreatic cell clusters (NPCCs). In this study, the mechanism underlying this was investigated.

METHODS

GFP expression was analyzed in porcine cells transfected with pEBVGFP by FACS analysis and confocal microscopy. The possible integration of pEBVGFP into the chromosomal DNA was analyzed by Southern blot. Self-replication of the EBV-based plasmid in porcine cells was investigated by PCR. The NPCCs were immunostained to characterize cells transfected with pEBVGFP.

RESULTS

The EBV based plasmid provided prolonged GFP expression in porcine cells and duct cells were the main cells transfected among NPCCs. Southern blot showed that the transfected pEBVGFP stayed for a long time as an episome rather than integrating into the chromosomal DNA. pEBVGFP isolated from the transfected porcine cells had methylated CpG suggesting that they self-replicated in those cells.

CONCLUSIONS

The EBV-based plasmid may be useful for genetically manipulating porcine cells to enhance their value as xenotransplantation sources.

Phase II study of capecitabine and cisplatin as first-line combination therapy in patients with gastric cancer recurrent after fluoropyrimidine-based adjuvant chemotherapy

To evaluate the efficacy and safety of capecitabine and cisplatin in patients with recurrent gastric cancer after fluoropyrimidine-based adjuvant therapy. Patients with histologically confirmed and measurable advanced gastric cancer that had relapsed after fluoropyrimidine-based adjuvant chemotherapy received oral capecitabine (1250 mg m⁻² twice daily, days 1–14) and intravenous cisplatin (60 mg m⁻² over 1 h, day 1) every 3 weeks. In total, 32 patients were enrolled, of whom 30 were evaluable for efficacy and 32 for safety. A median of 5 cycles (range 1–10) was administered. One patient achieved a complete response and eight had partial responses, giving an overall response rate of 28% (95% CI, 13–44%). The median time to progression and median overall survival were 5.8 months (95% CI, 4.1–7.5 months) and 11.2 months (95% CI, 5.5–16.9 months), respectively. Grade 3 neutropenia and thrombocytopenia were observed in 38 and 6% of patients, respectively. Grade 2/3 nonhaematological toxicities included diarrhoea (19%), stomatitis (19%) and hand-foot syndrome (31%). No grade 4 toxicity, neutropenic fever or treatment-related deaths occurred. Capecitabine in combination with cisplatin was effective and well tolerated as first-line treatment in patients with recurrent gastric cancer after fluoropyrimidine-based adjuvant chemotherapy.

A naturally derived gastric cancer cell line shows latency I Epstein-Barr virus infection closely resembling EBV-associated gastric cancer

In a process seeking out a good model cell line for Epstein-Barr virus (EBV)-associated gastric cancer, we found that one previously established gastric adenocarcinoma cell line is infected with type 1 EBV. This SNU-719 cell line from a Korean patient expressed cytokeratin without CD19 or CD21 expression. In SNU-719, EBNA1 and LMP2A were expressed, while LMP1 and EBNA2 were not. None of the tested lytic EBV proteins were detected in this cell line unless stimulated with phorbol ester. EBV infection was also shown in the original carcinoma tissue of SNU-719 cell line. Our results support the possibility of a CD21-independent EBV infection of gastric epithelial cells in vivo. As the latent EBV gene expression pattern of SNU-719 closely resembles that of the EBV-associated gastric cancer, this naturally derived cell line may serve as a valuable model system to clarify the precise role of EBV in gastric carcinogenesis.

Prolonged gene expression in primary porcine pancreatic cells using an Epstein-Barr virus-based episomal vector

Epstein-Barr virus (EBV)-based plasmids containing the origin of replication (oriP) and EBV nuclear antigen 1 (EBNA-1) are well known for the stable episomal maintenance in human cells. In order to clarify whether an EBV-based plasmid can be maintained stably in the porcine pancreatic cells which are the primary candidate sources of islet xenotransplantation, we constructed pEBVGFP encoding the green fluorescent protein (GFP). Monolayer culture of the porcine neonatal pancreatic cells was lipofected with pEBVGFP or pGFP which was derived from pEBVGFP by deleting out oriP and EBNA-1. pEBVGFP significantly prolonged GFP expression not only in human cell lines but also in the primary porcine pancreatic cells compared with pGFP. Interestingly, the duct cells that are believed as the pancreatic precursor cells were preferentially transfected and conveniently enriched among the mixed primary cell populations using a hygromycin B selection. To our knowledge, this is the first report suggesting the potential application of an EBV-based plasmid for the extended gene expression in the primary porcine pancreatic duct cells.

Phase II study of capecitabine plus cisplatin as first-line chemotherapy in advanced gastric cancer

BACKGROUND

A phase II study was conducted to assess the efficacy and tolerability of combination therapy with capecitabine and cisplatin in patients with advanced gastric cancer.

PATIENTS AND METHODS

Patients with previously untreated metastatic or unresectable measurable gastric adenocarcinoma received oral capecitabine 1250 mg/m(2) twice daily, days 1-14, and i.v. cisplatin 60 mg/m(2) on day 1. This cycle was repeated every 3 weeks.

RESULTS

Forty-two patients were enrolled in this study. Of these, 38 patients were assessable for efficacy and 40 were assessable for toxicity. One patient achieved a complete response and 22 patients had partial responses, giving an overall response rate of 54.8% in the intention-to-treat population (95% confidence interval 39.8% to 69.8%). The median time to progression was 6.3 months and the median overall survival was 10.1 months. The principal adverse events were neutropenia and hand-foot syndrome. Grade 3/4 adverse events were neutropenia (32.5% of patients), thrombocytopenia (10%), stomatitis (2.5%) and diarrhea (5%). Grade 2 and 3 hand-foot syndrome occurred in 20% and 7.5% of patients, respectively. There were no treatment-related deaths.

CONCLUSIONS

The combination of capecitabine and cisplatin is active and well tolerated in patients with advanced gastric cancer.

Desensitization to urine-derived gonadotropins in a woman with secondary infertility

BACKGROUND

Urine-derived gonadotropins have been used to treat infertility but may cause allergic reactions. IgE-mediated hypersensitivity reactions can be treated with desensitization, especially when new therapies such as recombinant human gonadotropins are unavailable.

OBJECTIVE

This case is described to highlight a successful intervention with desensitization in a woman with a complicated history of secondary infertility. She had been treated with ovulation-induction regimens, such as IVF-M (in vitro fertilization-human menopausal gonadotropin [hMG]) and IVF-C (human chorionic gonadotropin [hCG]), for intrauterine insemination. During treatment, however, she experienced reactions to IVF-M and IVF-C. Because she strongly wanted a baby and no alternative preparation was available, desensitization was attempted.

METHODS

Intradermal tests with IVF-M and IVF-C using both negative and positive controls were performed on the patient and four normal control subjects. Immediate wheal-and-flare reactions occurred only in the patient. ELISA and ELISA inhibition tests showed positive responses to IVF-M and IVF-C, but not to highly purified hMG, hCG, or D-mannitol, a preservative in IVF-M and IVF-C. Desensitization to IVF-M and IVF-C was done with a protocol used for parenteral desensitization to penicillin.

RESULTS

During the IVF-M desensitization, the intramuscular injections were well tolerated. For the next 2 days, daily administration of IVF-M was uneventful. Thirty-six hours later, desensitization to IVF-C was performed successfully. The patient had two intrauterine inseminations and became pregnant.

CONCLUSIONS

Nongonadotropin proteins in urine-derived gonadotropins cause IgE-mediated hypersensitivity reactions. Acute desensitization to urine-derived gonadotropins can be performed effectively, as shown in our current case.

Cellular changes induced by low-risk human papillomavirus type 11 in keratinocytes that stably maintain viral episomes

Infections by low-risk papillomavirus types, such as human papillomavirus (HPV) type 6 (HPV-6) and HPV-11, induce benign genital warts that rarely progress to malignancy. In contrast, lesions induced by high-risk HPV types have the potential to progress to cancer. Considerable information is available concerning the pathogenesis of high-risk HPV types, but little is known about the life cycle of low-risk HPV types. Although functionally distinct, both high- and low-risk virus types infect keratinocytes and induce virion production upon differentiation. This information suggests that they may share common mechanisms for regulating their productive life cycles. Using tissue culture methods developed to study high-risk HPV types, we examined the ability of HPV-11 to be stably maintained as episomes following transfection of normal human keratinocytes with cloned viral DNA. HPV-11 genomes were found to be maintained in keratinocytes for extended passages in cultures in 14 independent experiments involving transfection of cloned HPV-11 DNA. Interestingly, the HPV-11-positive cells exhibited an extended life span that averaged approximately twofold longer than that of control neomycin-transfected cells. In organotypic cultures, HPV-11-positive cells exhibited altered differentiation patterns, but the extent of disruption was less severe than that seen with high-risk HPV types. In addition, the amplification of HPV-11 DNA, as well as the induction of several viral messages, was observed following differentiation of transfected cells in semisolid media. To determine whether global changes in cellular gene expression induced by HPV-11 were similar to those observed with high-risk HPV-31 (Y. E. Chang and L. A. Laimins, J. Virol. 74:4174-4182, 2000), microarray analysis of 7,075 expressed sequences was performed. A spectrum of cellular genes different from that previously reported for HPV-31 was found to be activated or repressed by HPV-11. The expression of only a small set of genes was similarly altered by both high- and low-risk HPV types. This result suggests that different classes of HPVs have distinct effects on global cellular transcription patterns during infection. The methods described allow for a genetic analysis of HPV-11 in the context of its differentiation-dependent life cycle.

Telomerase activation by human papillomavirus type 16 E6 protein: induction of human telomerase reverse transcriptase expression through Myc and GC-rich Sp1 binding sites

High-risk human papillomaviruses (HPVs) immortalize keratinocytes by disrupting the retinoblastoma protein (Rb)/p16 pathway and activating telomerase. The E7 oncoprotein targets Rb, while the E6 oncoprotein induces telomerase activity in human keratinocytes. This study has examined the mechanism by which E6 activates telomerase. Expression of human telomerase reverse transcriptase (hTERT), the catalytic subunit of telomerase, was found to be increased in keratinocytes stably expressing HPV type 16 E6, suggesting that E6 acts to increase hTERT transcription. hTERT expression and telomerase activity were activated to significantly higher levels in cells expressing both E6 and E7 than in cells expressing E6 alone. This indicates that E7 may augment E6-mediated activation of hTERT transcription. In transient-transfection assays using hTERT reporters, the induction of hTERT expression by E6 was found to be mediated by a 258-bp fragment of the hTERT promoter, proximal to the ATG initiation codon. Previous studies have demonstrated that overexpression of Myc can activate hTERT expression, suggesting that Myc may be a mediator of E6-mediated hTERT induction. However, in cells stably expressing E6, no strict correlation between the level of Myc and the activation of hTERT was found. Consistent with this observation, mutation of the two Myc binding sites in the hTERT promoter only modestly reduced responsiveness to E6 in transient reporter assays. This indicates that activation of Myc-dependent transcription is not essential for E6-mediated upregulation of hTERT expression. The hTERT promoter also contains five GC-rich elements that can bind Sp1. Mutation of these sites within the 258-bp fragment partially reduced hTERT induction by E6. However, when mutations in the Sp1 sites were combined with the mutated Myc binding sites, all activation by E6 was lost. This indicates that it is the combinatorial binding of factors to Myc and Sp1 cis elements that is responsible for hTERT induction by E6.

Supramolecular assembly and acid resistance of Helicobacter pylori urease

Helicobacter pylori, an etiologic agent in a variety of gastroduodenal diseases, produces a large amount of urease, which is believed to neutralize gastric acid by producing ammonia for the survival of the bacteria. Up to 30% of the enzyme associates with the surface of intact cells upon lysis of neighboring bacteria. The role of the enzyme at the extracellular location has been a subject of controversy because the purified enzyme is irreversibly inactivated below pH 5. We have determined the crystal structure of H. pylori urease, which has a 1.1 MDa spherical assembly of 12 catalytic units with an outer diameter of approximately 160 A. Under physiologically relevant conditions, the activity of the enzyme remains unaffected down to pH 3. Activity assays under different conditions indicated that the cluster of the 12 active sites on the supramolecular assembly may be critical for the survival of the enzyme at low pH. The structure provides a novel example of a molecular assembly adapted for acid resistance that, together with the low Km value of the enzyme, is likely to enable the organism to inhabit the hostile niche.