Diagnostic Accuracy of Fecal Calprotectin for the Detection of Small Bowel Crohn’s Disease through Capsule Endoscopy: An Updated Meta-Analysis and Systematic Review

Background/Aims@#The diagnosis of small bowel Crohn’s disease with negative ileocolonoscopic findings has been challenging. Fecal calprotectin (FC) has been used to detect colonic inflammation, but its efficacy for detecting small bowel inflammation is less established. We performed an updated meta-analysis to evaluate the diagnostic accuracy of FC to detect active small bowel inflammation observed during capsule endoscopy. @*Methods@#We conducted a systematic literature search for studies that evaluated the correlation between small bowel inflammation and FC in patients with suspected/established Crohn’s disease. We calculated the pooled sensitivity, specificity, and diagnostic odds ratios (DORs) and constructed hierarchical summary receiver operating characteristic curves for FC cutoffs of 50, 100, and 200 µg/g. @*Results@#Fourteen studies were eligible for the final analysis. The DORs of all FC cutoffs were significant. The highest DOR was observed at 100 µg/g (sensitivity, 0.73; specificity, 0.73; and DOR, 7.89) and was suggested as the optimal diagnostic cutoff. If we analyzed only studies that included patients with suspected Crohn’s disease, the DOR was 8.96. If we analyzed only studies that included patients with a Lewis score ≥135 as a diagnostic criterion for active disease, the DOR was 10.90. @*Conclusions@#FC has significant diagnostic accuracy for detecting small bowel inflammation, and an FC cutoff of 100 µg/g can be used as a tool to screen for small bowel Crohn’s disease.

Diagnostic Accuracy of Fecal Calprotectin for the Detection of Small Bowel Crohn’s Disease through Capsule Endoscopy: An Updated Meta-Analysis and Systematic Review

Background/Aims@#The diagnosis of small bowel Crohn’s disease with negative ileocolonoscopic findings has been challenging. Fecal calprotectin (FC) has been used to detect colonic inflammation, but its efficacy for detecting small bowel inflammation is less established. We performed an updated meta-analysis to evaluate the diagnostic accuracy of FC to detect active small bowel inflammation observed during capsule endoscopy. @*Methods@#We conducted a systematic literature search for studies that evaluated the correlation between small bowel inflammation and FC in patients with suspected/established Crohn’s disease. We calculated the pooled sensitivity, specificity, and diagnostic odds ratios (DORs) and constructed hierarchical summary receiver operating characteristic curves for FC cutoffs of 50, 100, and 200 µg/g. @*Results@#Fourteen studies were eligible for the final analysis. The DORs of all FC cutoffs were significant. The highest DOR was observed at 100 µg/g (sensitivity, 0.73; specificity, 0.73; and DOR, 7.89) and was suggested as the optimal diagnostic cutoff. If we analyzed only studies that included patients with suspected Crohn’s disease, the DOR was 8.96. If we analyzed only studies that included patients with a Lewis score ≥135 as a diagnostic criterion for active disease, the DOR was 10.90. @*Conclusions@#FC has significant diagnostic accuracy for detecting small bowel inflammation, and an FC cutoff of 100 µg/g can be used as a tool to screen for small bowel Crohn’s disease.

Association study between OCTN1 functional haplotypes and Crohn's disease in a Korean population

Crohn's disease (CD) is a chronic inflammatory bowel disease with multifactorial causes including environmental and genetic factors. Several studies have demonstrated that the organic cation/carnitine transporter 1 (OCTN1) non-synonymous variant L503F is associated with susceptibility to CD. However, it was reported that L503F is absent in Asian populations. Previously, we identified and functionally characterized genetic variants of the OCTN1 promoter region in Koreans. In that study, four variants demonstrated significant changes in promoter activity. In the present study, we determined whether four functional variants of the OCTN1 promoter play a role in the susceptibility to or clinical course of CD in Koreans. To examine it, the frequencies of the four variants of the OCTN1 promoter were determined by genotyping using DNA samples from 194 patients with CD and 287 healthy controls. Then, associations between genetic variants and the susceptibility to CD or clinical course of CD were evaluated. We found that susceptibility to CD was not associated with OCTN1 functional promoter variants or haplotypes showing altered promoter activities in in vitro assays. However, OCTN1 functional promoter haplotypes showing decreased promoter activities were significantly associated with a penetrating behavior in CD patients (HR=2.428, p=0.009). Our results suggest that the OCTN1 functional promoter haplotypes can influence the CD phenotype, although these might not be associated with susceptibility to this disease.

A Case of Synchronous Squamous Cell Carcinoma in the Esophagus and Stomach

Synchronous esophageal and gastric cancers with the pathologic features of a squamous cell carcinoma are extremely rare. A 57-year-old male visited our hospital with a history of hematemesis and was diagnosed with a synchronous cancer. He underwent a staging work-up, and the resectable lesion in the stomach was operated on following radiologic and endoscopic evaluations. The pathologic examination revealed a synchronous cancer consisting of squamous cell carcinoma in the distal esophagus and the cardia of the stomach. We report a case of a synchronous cancer that was successfully treated by surgical resection followed by concurrent chemoradiotherapy. We also discuss the hypothesis regarding the origin and presentation of the synchronous cancer and highlight the importance of careful surveillance by physicians at the time of diagnosis.

Development and Preliminary Evaluation of a Leukocyte Removal Aptamer Filter / 대한수혈학회지

BACKGROUND: Leukocyte reduction filters are widely used to prevent transfusion reactions caused by leukocytes in blood components. Commercial filters are not sufficient for removal of leukocytes for prevention of transfusion associated graft-versus-host disease; therefore, irradiation of blood components was performed using expensive equipment. Techniques using an aptamer substituted for antibody have been developed and are available in clinical areas. The purpose of this study is to develop the aptamer filter system and to evaluate its efficiency and the possibility of its clinical application. METHODS: Aptamers targeted to CD45 were selected by the Postech Aptamer Initiative. The aptamer filter in which aptamers attached to beads were bound to leukocytes and removed by magnetic field was developed. Filtration of 14 units of leukoreduction-red blood provided by Korean Red Cross Blood Services was performed using aptamer filters. Leukocyte removal rate and red cell recovery rate were evaluated and bacterial culture was performed. RESULTS: After filtration using the aptamer filters, 45.6% of leukocytes were additionally removed and the red cell recovery rate was 92.8%. No growth in the bacterial culture was observed. CONCLUSION: In order to apply the cell depletion technique utilizing an aptamer to blood filter system, we developed and evaluated the aptamer filter system. Through improvement of the binding efficiency of the aptamer and the filtering process, and application of the various aptamers for other different cells, we suggest that this technique can be applied in the clinical area, such as a substitution for the irradiation process for TAGVHD prevention.

Clinical Significance of the Detection of Antinuclear Antibodies in Patients with Acute Hepatitis A

BACKGROUND/AIMS: The findings of several recent studies suggest that antinuclear antibodies (ANAs) are frequently detected in patients with acute hepatitis A (AHA). However, the clinical significance of a positive ANA test remains uncertain. This study was performed to evaluate the clinical significance of ANAs in AHA patients. METHODS: All patients admitted with AHA were consecutively enrolled in this study. An ANA assay was performed by indirect immunofluorescence during hospitalization. ANA positivity was defined as an ANA titer > or =1:80. The peak international normalized ratio (INR), peak alanine aminotransferase (ALT) and peak bilirubin levels were assessed over the duration of the hospitalization, and the incidence of AHA complications was evaluated. RESULTS: A total of 422 patients were enrolled in this study (age, 31+/-7 years), of which 260 (61.6%) were men. ANAs were detected in 179 AHA patients (42.4%). The proportion of ANA-positive patients varied significantly with AHA status on the day of the ANA assay (4.7% during the prodromal period vs 52.1% during the icteric or recovery period, p<0.001) and sex (56.2% in women vs 33.8% in men, p<0.001). The ANAs became undetectable in all ANA-positive patients within 3 months. The incidence of complications, including mortality, fulminant hepatic failure, renal dysfunction, relapse, and cholestatic hepatitis, did not differ significantly between ANA-positive and ANA-negative patients. CONCLUSIONS: ANAs were detected frequently and transiently in patients with AHA, especially after their peak-ALT day. The presence of ANAs may not be associated with the clinical outcome of AHA, but simply with AHA status on the ANA assay day.

Fanconi's Syndrome Associated with Prolonged Adefovir Dipivoxil Therapy in a Hepatitis B Virus Patient

Adefovir dipivoxil (ADV) is commonly used as an antiviral agent in the treatment of chronic hepatitis B or human immunodeficiency virus infection. Nephrotoxicity has been shown to occur at daily dosages of 60-120 mg. Fanconi's syndrome is a generalized dysfunction of the renal proximal tubular cells, which is usually accompanied by complications. Here we report a case of Fanconi's syndrome in a chronic hepatitis B patient who had been treated with a prolonged regimen of ADV at 10 mg/day. A 47-year-old man complained of severe back and chest-wall pain. He had chronic hepatitis B and had been treated with ADV at a daily dose of 10 mg for 38 months. He was hospitalized because of severe bone pain, and laboratory and radiologic findings suggested a diagnosis of Fanconi's syndrome with osteomalacia. After discontinuation of the ADV, he recovered and was discharged from hospital. His laboratory findings had normalized within 2 weeks. This case indicates that Fanconi's syndrome can be acquired by a chronic hepatitis B patient taking ADV at a conventional dosage of 10 mg/day. Therefore, patients treated with long-term ADV should be checked regularly for the occurrence of ADV-induced Fanconi's syndrome.

Risk Factors for Treatment Failure and Recurrence after Metronidazole Treatment for Clostridium difficile-associated Diarrhea

BACKGROUND/AIMS: The incidence of treatment failure or recurrence of Clostridium difficile-associated diarrhea (CDAD) following metronidazole treatment has increased recently. We studied the treatment failure, recurrence rate, and risk factors predictive of treatment failure and recurrence after metronidazole treatment for CDAD. METHODS: We retrospectively identified consecutive patients who were admitted and treated for CDAD at a single tertiary institution in Korea over a recent 10-year period (i.e., 1998-2008). RESULTS: Metronidazole was administered as the initial treatment to 111 of 117 patients (94.9%) with CDAD. Fourteen patients (12.6%) had no clinical response to the metronidazole treatment, and in 13 patients (13.4%) CDAD recurred after successful metronidazole treatment. Diabetes mellitus (p=0.014) and sepsis (p=0.002) were independent risk factors for metronidazole treatment failure. Patients who had received surgery within 1 month before CDAD developed were more likely to experience a recurrence after metronidazole treatment (p=0.032). Vancomycin exhibited a higher response rate after treatment failure, and metronidazole showed a reasonable response rate in the treatment of recurrence. Treatment failure and recurrence rates increased with time after metronidazole treatment for CDAD over the 10-year study period. CONCLUSIONS: Our data suggest that diabetes mellitus and sepsis are independent risk factors for metronidazole treatment failure, and that operation history within 1 month of development of CDAD is a predictor of a recurrence after metronidazole treatment.

Colitis Cystica Profunda Masquerading as a Pneumatosis Cystoides Intestinalis: A Case Report

Colitis Cystica Profunda (CCP) is an uncommon and benign disease entity characterized by mucoid cysts located in the submucosal layer of the colon. It can mimic cystic submucosal tumors or mucinous adenocarcinoma and is usually located in the rectum. CCP is found in the ascending colon less frequently. CCP manifesting as multiple cystic tumors, similar to pneumatosis cystoides intestinalis, has not yet been reported. Recently, a case of CCP mimicking pneumatosis cystoides intestinalis in the ascending colon was treated. Here this case is reported and the literature reviewed.

Detection of Human Cytomegalovirus (HCMV) and Porcine Endogenous Retrovirus (PERV) with One Step Extraction Method

BACKGROUND: Xenotransplantation is thought to be one of the alternative methods to overcome the shortage of human organs for transplantation. Recipients should be immunosuppressed for graft survival, and thus, there is a need for developing diagnostic modality that can detect diverse infections originating from animals and recipients rapidly, in the early stage, and with high sensitivity using small volume of samples. This study was carried out to develop a fast, simple, and robust technique for the preparation of HCMV DNA and PERV RNA using small volume of samples. MATERIALS AND METHODS: Nucleic acids were extracted from serially diluted samples with one step extraction method as well as with Qiagen kit. The presence of genomic DNA of human cytomegalovirus (HCMV) and porcine endogenous retrovirus (PERV) was detected by PCR and specific primer set, respectively. RNA of HCMV and PERV was extracted and then detected by RT-PCR and specific primer set, respectively. For absolute quantification of HCMV, standard curve was established by real time PCR. RESULTS: HCMV DNA and PERV RNA were prepared from culture supernatant and cells for PCR or RT-PCR with one step extraction method. It was possible to extract both the DNA and RNA from the samples in about 20 minutes with one step extraction method in a single tube. HCMV and PERV could also be detected by PCR and one step extraction method, respectively. It was also good with small quantity samples. CONCLUSIONS: One step extraction method is simpler and faster method than other extraction methods when there are two types of DNA and RNA viruses in one sample. From these results, we could see that the one step extraction method could be very useful in detecting HCMV and PERV rapidly from the pig cells or organ transplanted recipients with a small amount of sample.

Clinical Experience of Thalidomide in the Treatment of Korean Patients with Intestinal Behcet's Disease: Pilot Experience in a Single Center

Intestinal Behcet's disease (BD) often leads to severe complications, such as perforation or massive bleeding, and therefore is one of the major causes of morbidity and mortality. As thalidomide has been identified and its anti-inflammatory and immunomodulatory properties clarified, this drug has been used in cases of systemic BD with some success. Herein we report a case series of four patients with intestinal BD to share our clinical experience with thalidomide treatment. We studied the effects of thalidomide in four patients who had a chronic relapse of intestinal BD requiring the frequent use of systemic steroids due to refractoriness to prior treatments, such as 5-aminosalycylic acid and immunosuppressants. Pre- and post-treatment clinical and laboratory data, including clinical symptoms, laboratory data, disease activity index for intestinal BD, and thalidomide toxicity were recorded. Three of the four patients had a clinical and radiologic improvement after thalidomide treatment and all of the patients discontinued steroid therapy. Although two patients tolerated thalidomide, two patients could not continue the treatment because they suffered from edema and neutropenia. Thalidomide could be considered a therapeutic option for the treatment of intestinal BD.

Clinical Experience of Thalidomide in the Treatment of Korean Patients with Intestinal Behcet's Disease: Pilot Experience in a Single Center

Intestinal Behcet's disease (BD) often leads to severe complications, such as perforation or massive bleeding, and therefore is one of the major causes of morbidity and mortality. As thalidomide has been identified and its anti-inflammatory and immunomodulatory properties clarified, this drug has been used in cases of systemic BD with some success. Herein we report a case series of four patients with intestinal BD to share our clinical experience with thalidomide treatment. We studied the effects of thalidomide in four patients who had a chronic relapse of intestinal BD requiring the frequent use of systemic steroids due to refractoriness to prior treatments, such as 5-aminosalycylic acid and immunosuppressants. Pre- and post-treatment clinical and laboratory data, including clinical symptoms, laboratory data, disease activity index for intestinal BD, and thalidomide toxicity were recorded. Three of the four patients had a clinical and radiologic improvement after thalidomide treatment and all of the patients discontinued steroid therapy. Although two patients tolerated thalidomide, two patients could not continue the treatment because they suffered from edema and neutropenia. Thalidomide could be considered a therapeutic option for the treatment of intestinal BD.

Wernicke's Encephalopathy in Advanced Gastric Cancer / Journal of the Korean Cancer Association, 대한암학회지

PURPOSE: With their prolonged survival and malnutrition, cancer patients, and especially gastrointestinal (GI) tract cancer patients, can develop Wernicke's encephalopathy (WE). The aim of this study is to remind physicians of the importance of WE and prompt management in patients with GI tract cancer. MATERIALS AND METHODS: This study is a retrospective review of 2 cases of WE in advanced gastric cancer (AGC) patients, and we review the literature for cases of GI tract cancer related to WE. RESULTS: A 48-year-old female with AGC presented dizziness and diplopia for 5 days and a 20 kg weight loss. Neurologic exam showed nystagmus and gaze disturbance. Her symptoms improved after daily parenteral injection of thiamine 100 mg for 17 days. A 58-year-old female with AGC presented with sudden disorientation, confusion and 15 kg weight loss. Neurologic exam showed gaze limitation and mild ataxia. Despite daily parenteral injection of thiamine 100 mg for 4 days, she died 5 days after the onset of neurologic symptoms. Combining the cases noted in the literature review with our 2 cases, the 7 gastric cancer cases and 2 colorectal cancer cases related to WE showed similar clinical characteristics; 1) a history of long-period malnutrition and weight loss, 2) relatively typical neurologic signs and symptoms and 3) specific magnetic resonance image findings. Except for 2 patients who had irreversible neurologic symptoms, the other 7 patients were improved with prompt thiamine treatment. CONCLUSION: It is important to consider WE in GI tract cancer patients with acute neurologic symptoms and who are in a state of malnutrition. Thiamine should be given as soon as possible when WE is suspected.

The relationship between hepatitis B virus infection and the incidence of pancreatic cancer: a retrospective case-control study / 대한간학회지

BACKGROUND/AIMS: An association between past history of hepatitis B virus (HBV) infection and pancreatic cancer (PC) has recently been reported. We investigated whether HBV and hepatitis C virus (HCV) infections are associated with the development of PC in Korea. METHODS: We retrospectively recruited patients with PC and sex- and, age-matched control patients with stomach cancer (SC) during the previous 5 years. Serum HBsAg and anti-HCV were examined, and data on smoking, alcohol intake, diabetes, and the history of chronic pancreatitis (CP) were collected. RESULTS: A total of 506 PC and 1008 SC were enrolled, with respectively 58.1% and 97.3% of these cases being confirmed histologically. The mean age and sex ratio (male:female) were 63.5 years and 1.5:1 in the PC patients and 63.9 years and 1.5:1 in the SC patients respectively (P>0.05). The odds ratios (95% confidence interval, 95% CI) in univariate analysis were 0.90 (0.52-1.56; P=0.70) for HBsAg, 1.87 (0.87-4.01; P=0.11) for anti-HCV, 2.66 (2.04-3.48; P<0.001) for the presence of diabetes, 2.30 (1.83-2.90; P<0.001) for smoking, 1.14 (0.89-1.46; P=0.31) for alcohol intake, and 4.40 (1.66-11.66; P=0.003) for the history of CP. Independent risk factors for PC were presence of diabetes (OR, 2.67; 95% CI, 2.00-3.56; P<0.001), smoking (OR, 2.49; 95% CI, 1.93-3.21; P<0.001) and history of CP (OR, 4.60; 95% CI, 1.56-13.53; P=0.006). CONCLUSIONS: There was no significant association between seropositivity for HBsAg or anti-HCV and PC. Further studies are warranted to clarify the association between HBV infection and PC in regions where HBV is endemic.

No Evidence of the Productive Replication of Porcine Endogenous Retrovirus (PERV) from SNU Miniature Pigs in Human Cell Line

BACKGROUND: The presence of porcine endogenous retrovirus (PERV) has been considered as one of the main hurdles to transplant pig's organs or tissues to human beings. There has been no report that PERV infection is associated with human diseases. Because pigs have their own characteristics of PERV according to pig strain, it is necessary to analyze the infectivity of PERV from SNU miniature pig to human cells for future utilization as a transplantation donor. MATERIALS AND METHODS: Human cell lines were infected with culture supernatant from porcine cell line or immunomodulator-stimulated peripheral blood mononuclear cells (PBMC) of SNU miniature pigs. They were also co-cultured with PBMC or islet cells of SNU miniature pigs. The presence of PERV genes and general pig marker gene in cells was determined by nested PCR with primer set for PERV pol and pig mitochondrial cytochrome oxidase II (COII), respectively. RESULTS: Infection test with the culture supernatant from PBMC of SNU miniature pigs showed that PERV pol but not COII was detected only in a few cases, but there was no uniform infection pattern in scope of stimulators and cell types. PERV pol was not demonstrated in co-cultures of human cell line with PBMC or islet cells from SNU miniature pigs after 80 days of co-cultures. CONCLUSIONS: In vitro infectivity test suggests that PERV from SNU miniature pig might not replicate productively in human cell lines although it could infect human cells and integrate into chromosome.

A Case of Combined Hepatocellular-Cholangiocarcinoma with Favorable Response to Systemic Chemotherapy / Journal of the Korean Cancer Association, 대한암학회지

Combined hepatocellular-cholangiocarcinoma (cHCC-CC) is a rare form of primary liver cancer composed of cells with histopathologic features of both hepatocellular carcinoma (HCC) and cholangiocarcinoma (CC). Because of its low incidence, the information on clinical outcomes of cHCC-CC is very limited and there are no published reports describing non-surgical treatment options for cHCC-CC. We report a case of cHCC-CC exhibiting a favorable response to systemic chemotherapy with doxorubicin and cisplatin. A 62-year-old man who recurred after a right lobectomy for cHCC-CC received sorafenib for palliative systemic therapy, but follow up imaging studies showed disease progression. He received 2nd line chemotherapy with doxorubicin at 60 mg/m2 together with cisplatin at 70 mg/m2. After 2 cycles of chemotherapy, a computed tomography scan of the chest showed markedly decreased size and number of the multiple lung metastases. After completing 8 cycles of 2nd line therapy, we changed the regimen to a fluorouracil (5-FU) mono therapy because of the toxicities associated with doxorubicin and cisplatin. To date, the patient has completed his 15th cycle of 5-FU mono therapy with the disease status remaining stable during 18 months of follow-up.

Usefulness of Non-invasive Markers for Predicting Significant Fibrosis in Patients with Chronic Liver Disease

The purpose of this prospective study was to verify and compare the strengths of various blood markers and fibrosis models in predicting significant liver fibrosis. One hundred fifty-eight patients with chronic liver disease who underwent liver biopsy were enrolled. The mean age was 41 yr and male patients accounted for 70.2%. The common causes of liver disease were hepatitis B (67.7%) and C (16.5%) and fatty liver (9.5%). Stages of liver fibrosis (F0-4) were assessed according to the Batts and Ludwig scoring system. Significant fibrosis was defined as > or =F2. Sixteen blood markers were measured along with liver biopsy, and estimates of hepatic fibrosis were calculated using various predictive models. Predictive accuracy was evaluated with a receiver-operating characteristics (ROC) curve. Liver biopsy revealed significant fibrosis in 106 cases (67.1%). On multivariate analysis, alpha2-macroglobulin, hyaluronic acid, and haptoglobin were found to be independently related to significant hepatic fibrosis. A new predictive model was constructed based on these variables, and its area under the ROC curve was 0.91 (95% confidence interval, 0.85-0.96). In conclusion, alpha2-macroglobulin, hyaluronic acid, and haptoglobin levels are independent predictors for significant hepatic fibrosis in chronic liver disease.

Characterization of Clones of Human Cell Line Infected with Porcine Endogenous Retrovirus (PERV) from Porcine Cell Line, PK-15

BACKGROUND: Porcine endogenous retroviruses (PERVs) form part of the chromosomes of all pigs. Since they can be produced as infectious virion and infect human cells, safety issues on PERVs infection to human are still controversial and is one of main hurdles of xenotransplantation using pig cells or organs. It has been reported that the established porcine cell line, PK-15, produces PERVs and can infect the human cell lines. Therefore, clonal analysis on human cell line infected with PERV is a prerequisite to characterize the infectivity to human cells and to investigate the harmfulness of PERVs to human. MATERIALS AND METHODS: For the characterization of PERV that originates from porcine cell line, PK-15, full length PERV cloning from genomic DNA of PK-15 was performed and partial sequences of both ends were achieved. Cell clones from human cell line, 293, persistently infected with PERVs from PK-15 were established by the method of limiting dilution. Nested PCR and direct sequencing of PCR products in each clone were carried out so as to confirm the PERV genomes in each clone. The growth rate of each clone was checked using cell counting and 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide (MTT) assay, the infectivity by reverse transcriptase (RT) assay, and genetic analysis by karyotyping. RESULTS: A total of 12 genomic PERV clones could be retrieved; 1 with full length, 4 with defective forms, and others with irrelevant sequences. Intact PERV was thought to be able to infect 293 and the PERV-infected cell clones were selected by limiting dilution. PCR results confirmed that nine cell clones were infected with PERV, and sequence alignment data on PCR products of pol region from PK-15 and human cell clones with PERV showed very similar results. Cell counting and MTT assay for growth kinetics of each clone indicated that two clones showed reduced growth rate. However, it was difficult to verify the effect of PERV infection on the cell growth because of the presence of many genetic alterations in 293 parental cells. No RT activities were detected in the culture supernatant from PERV-infected 293 cell clones. CONCLUSION: The sequences of PERVs were detected in human cell clones after PERV infection, but PERV virions could not be detected from the culture supernatant by RT assay.

Characterization of Clones of Human Cell Line Infected with Porcine Endogenous Retrovirus (PERV) from Porcine Cell Line, PK-15

BACKGROUND: Porcine endogenous retroviruses (PERVs) form part of the chromosomes of all pigs. Since they can be produced as infectious virion and infect human cells, safety issues on PERVs infection to human are still controversial and is one of main hurdles of xenotransplantation using pig cells or organs. It has been reported that the established porcine cell line, PK-15, produces PERVs and can infect the human cell lines. Therefore, clonal analysis on human cell line infected with PERV is a prerequisite to characterize the infectivity to human cells and to investigate the harmfulness of PERVs to human. MATERIALS AND METHODS: For the characterization of PERV that originates from porcine cell line, PK-15, full length PERV cloning from genomic DNA of PK-15 was performed and partial sequences of both ends were achieved. Cell clones from human cell line, 293, persistently infected with PERVs from PK-15 were established by the method of limiting dilution. Nested PCR and direct sequencing of PCR products in each clone were carried out so as to confirm the PERV genomes in each clone. The growth rate of each clone was checked using cell counting and 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide (MTT) assay, the infectivity by reverse transcriptase (RT) assay, and genetic analysis by karyotyping. RESULTS: A total of 12 genomic PERV clones could be retrieved; 1 with full length, 4 with defective forms, and others with irrelevant sequences. Intact PERV was thought to be able to infect 293 and the PERV-infected cell clones were selected by limiting dilution. PCR results confirmed that nine cell clones were infected with PERV, and sequence alignment data on PCR products of pol region from PK-15 and human cell clones with PERV showed very similar results. Cell counting and MTT assay for growth kinetics of each clone indicated that two clones showed reduced growth rate. However, it was difficult to verify the effect of PERV infection on the cell growth because of the presence of many genetic alterations in 293 parental cells. No RT activities were detected in the culture supernatant from PERV-infected 293 cell clones. CONCLUSION: The sequences of PERVs were detected in human cell clones after PERV infection, but PERV virions could not be detected from the culture supernatant by RT assay.

The Effect of Peppermint Oil on Peristalsis during Gastroscopy / 대한소화기내시경학회지

BACKGROUND/AIMS: Gastrointestinal peristalsis may hinder inspection of the gastrointestinal track or its treatment during endoscopy. Antispasmodic agents such as hyoscine-N-butylbromide are commonly administered before endoscopy for alleviating peristalsis, although it causes unwanted complications. Peppermint oil (PMO) has a spasmolytic effect on viscera and it has been used as an adjunctive remedy for some disorders. We evaluated the antispasmodic effect of PMO solution during gastroscopy, and we determined if there are any adverse effects. METHODS: 1.6% PMO solution was sprayed on the antrum of the examinees (n=40) during gastroscopy. Observation was performed 5 cm ahead of the pyloric ring to count the peristaltic waves for 3 minutes before and after spraying PMO. The intensity of peristalsis was graded from 0 (none) to 4 (severe), and the pulse rate of all the examinees was recorded every minute. RESULTS: The number of peristaltic contractions decreased after PMO spraying from 7.02+/-2.25 to 3.17+/-2.57 times/3 minutes (p<0.01). The peristaltic intensity also decreased from 3.15+/-1.18 to 1.34+/- \0.95 (p<0.01) with a difference of 1.80+/-1.29. On observing the examinees' pulse rates, using PMO did not induce tachycardia. No adverse effect during and after the investigation with PMO solution was reported. CONCLUSIONS: PMO showed a significant antispasmodic effect, and it reduced the number of peristaltic contractions and the intensity of gastric peristalsis. It also did not have any significant side effects. PMO solution may be used as an effective antispasmodic agent during gastroscopy.