Inhibition of marine biofouling by aquatic Actinobacteria and coral-associated marine bacteria

Aims: Biofouling is a common biology phenomenon occuring on ship surface. This phenomenon has become serious threat in marine industries because of great economic loss. Tributyltin has been used to prevent biofouling, but it turned to cause the environmental problem. Therefore, the discovery of alternative environment-friendly compound is necessarily needed. Methodology and results: Five Actinobacteria isolates and fourteen marine bacteria isolates were tested against the biofilm formation of eight biofouling bacteria isolates that isolated from boat surface and the attachment of three biofouling diatoms (Amphora, Navicula, Nitzschia). Actinobacteria CW17 supernatant showed the broad spectrum activity against all fouling bacteria, whereas BC 11-5 supernatant was the only marine bacteria that capable to inhibit biofilm formation of V. neocaledonicus. Moreover, three representative diatoms attachment could be inhibited by the bioactive compounds produced by Actinobacteria and marine bacteria. CW01 supernatant showed broad spectrum and high activity against all three representative diatoms which is very promising. Molecular identification based on 16S rDNA gene sequence showed eight fouling bacteria isolates were biofilm-forming bacteria. Conclusions, significance and impact of study: This research showed aquatic Actinobacteria and coral-associated marine bacteria have the potential to prevent biofouling formation. Further studies are needed to purify and characterize these antibiofouling compounds for environmental application.

Protective effect of the standardized green tea seed extract on UVB-induced skin photoaging in hairless mice

BACKGROUND/OBJECTIVES: Ultraviolet B (UVB) irradiation on skin can induce production of reactive oxygen species (ROS), which cause expression of matrix metalloproteinases (MMPs) and collagen degradation. Thus, chronic exposure of skin to UVB irradiation leads to histological changes consistent with aging, such as wrinkling, abnormal pigmentation, and loss of elasticity. We investigated the protective effect of the standardized green tea seed extract (GSE) on UVB-induced skin photoaging in hairless mice. MATERIALS/METHODS: Skin photoaging was induced by UVB irradiation on the back of Skh-1 hairless mice three times per week and UVB irradiation was performed for 10 weeks. Mice were divided into six groups; normal control, UVB irradiated control group, positive control (UVB + dietary supplement of vitamin C 100 mg/kg), GSE 10 mg/kg (UVB + dietary supplement of GSE 10 mg/kg), GSE 100 mg/kg (UVB + dietary supplement of GSE 100 mg/kg), and GSE 200 mg/kg (UVB + dietary supplement of GSE 200 mg/kg). RESULTS: The dietary supplement GSE attenuated UVB irradiation-induced wrinkle formation and the decrease in density of dermal collagen fiber. In addition, results of the antioxidant analysis showed that GSE induced a significant increase in antioxidant enzyme activity compared with the UVB irradiation control group. Dietary supplementation with GSE 200 mg/kg resulted in a significant decrease in expression of MMP-1, MMP-3, and MMP-9 and an increase in expression of TIMP and type-1 collagen. CONCLUSIONS: Findings of this study suggest that dietary supplement GSE could be useful in attenuation of UVB irradiation-induced skin photoaging and wrinkle formation due to regulation of antioxidant defense systems and MMPs expression.

Protective effect of the standardized green tea seed extract on UVB-induced skin photoaging in hairless mice

BACKGROUND/OBJECTIVES: Ultraviolet B (UVB) irradiation on skin can induce production of reactive oxygen species (ROS), which cause expression of matrix metalloproteinases (MMPs) and collagen degradation. Thus, chronic exposure of skin to UVB irradiation leads to histological changes consistent with aging, such as wrinkling, abnormal pigmentation, and loss of elasticity. We investigated the protective effect of the standardized green tea seed extract (GSE) on UVB-induced skin photoaging in hairless mice. MATERIALS/METHODS: Skin photoaging was induced by UVB irradiation on the back of Skh-1 hairless mice three times per week and UVB irradiation was performed for 10 weeks. Mice were divided into six groups; normal control, UVB irradiated control group, positive control (UVB + dietary supplement of vitamin C 100 mg/kg), GSE 10 mg/kg (UVB + dietary supplement of GSE 10 mg/kg), GSE 100 mg/kg (UVB + dietary supplement of GSE 100 mg/kg), and GSE 200 mg/kg (UVB + dietary supplement of GSE 200 mg/kg). RESULTS: The dietary supplement GSE attenuated UVB irradiation-induced wrinkle formation and the decrease in density of dermal collagen fiber. In addition, results of the antioxidant analysis showed that GSE induced a significant increase in antioxidant enzyme activity compared with the UVB irradiation control group. Dietary supplementation with GSE 200 mg/kg resulted in a significant decrease in expression of MMP-1, MMP-3, and MMP-9 and an increase in expression of TIMP and type-1 collagen. CONCLUSIONS: Findings of this study suggest that dietary supplement GSE could be useful in attenuation of UVB irradiation-induced skin photoaging and wrinkle formation due to regulation of antioxidant defense systems and MMPs expression.

Risk Factors for Anastomotic Leakage after Laparoscopic Rectal Resection

PURPOSE: The anastomotic leakage rate after rectal resection has been reported to be approximately 2.5-21 percent, but most results were associated with open surgery. The aim of this study was to identify risk factors and their relationship to the experience of the surgeon for anastomotic leakage after laparoscopic rectal resection. METHODS: Between March 2003 and December 2008, 156 patients underwent a laparoscopic rectal resection without a diverting ileostomy. The patients' characteristics, the details of treatment, the intraoperative results, and the postoperative results were recorded prospectively. Univariate and multivariate analyses were applied to identify risk factors for anastomotic leakage. RESULTS: The majority of operations were performed for malignant disease (n = 150; 96.2%), and 96 patients (61.5%) were males. Conversion to open surgery occurred in 1 case (0.6%). The anastomotic leak rate was 10.3% (16/156), and there were no mortalities. In the univariate analysis, tumor location, anastomotic level, intraoperative events, and operation time were associated with increased anastomotic leakage rate. In the multivariate analysis, anastomotic level (odds ratio [OR], 6.855; 95% confidence interval [CI], 1.271 to 36.964) and operation time (OR, 8.115; 95% CI, 1.982 to 33.222) were significantly associated with anastomotic leakage. CONCLUSION: The important risk factors for anastomotic leakage after laparoscopic rectal resection without a diverting ileostomy were low anastomosis and long operation time. An additional procedure, such as diverting stoma, may reduce the anastomotic leakage if it is selectively applied in cases with these risk factors.

Histological Differences between Vascular and Mucosal Hemorrhoids

PURPOSE: The aim of this study is to compare and analyze the histological differences between vascular and mucosal hemorrhoids, two structurally different types of hemorrhoids. METHODS: Internal hemorrhoidal tissue samples were fixed in 10% Formalin solution, and coronal sections included 10-mm proximal and 5-mm distal of the dentate line. Routine Masson-Trichrome and H&E were performed to evaluate the thickness of the mucosa and changes in the structure and the densities of submucosal vessels, connective tissue, and muscle. RESULTS: Compared with the corresponding tissues of mucosal hemorrhoids, the submucosal connective tissue and perivascular connective tissue of vascular hemorrhoids showed a loosened density, severe fragmentation, and an irregular arrangement. The submucosal vascular dilatation was more frequent and more severe in vascular hemorrhoids, but the number of vessels between both types of hemorrhoids did not show much difference. Hypertrophy and regular arrangement of the submucosal muscles were observed more frequently in the mucosal than in the vascular hemorrhoids. CONCLUSION: Compared to mucosal hemorrhoids, vascular hemorrhoids showed augmented damage in submucosal connective tissue and intense dilatation of vessels with a thinner mucosa. On the other hand, compared to vascular hemorrhoids, mucosal hemorrhoids showed hypertrophy of submucosal muscle and relatively minor alterations in vessels with a thicker mucosa. These histological differences may provide the basis for different etiologies between vascular and mucosal hemorrhoids.

The Role of Rectoanal Inhibitory Reflex in the Anal Continence Function

PURPOSE: The rectoanal inhibitory reflex (RAIR) aids the anal continence function by a sampling process. On the other hand, it might impair the anal continence function because the internal anal sphincter is relaxed during the reflex. We assessed the parameters of RAIR in incontinent patients with or without a sphincter defect and compared them with healthy control subjects to clarify the exact role of that reflex in the anal continence function. METHODS: The recovery time, slope, amplitude, and area under the reflex curve of the RAIR were measured for 31 normal controls without any history of anorectal surgery (group A), 32 incontinent patients with a sphincter defect (group B), and 49 incontinent patients without a sphincter defect (group C). Incontinence was defined as bowel accidents of more than 3 by the Cleveland Clinic Florida score. A sphincteric defect was defined endoanal sonographically. The mean ages of group A, B, and C were 57.9+/-14.3, 54.5+/-13.6, and 61.8+/-15.4 years, respectively. RESULTS: When group A and group B+C were compared, the recovery times (seconds) were 17.5+/-3.5 and 14.8+/-5.5 (P=.003), the slopes (mmHg/second) were 0.67+/-3.04 and 3.27+/-2.44 (P<.001), the amplitudes (%) were 7.0+/-16.5 and 53.3+/-19.4 (P=.352), and the area under the reflex curve (mmHg*seconds) were 230.2+/-102.15 and 173.0+/-140.8 (P=.020). When group B and group C were compared, the recovery times were 15.0+/-5.8 and 14.7+/-5.3 (P=.828), the slopes were 3.6+/-2.8 and 3.1+/-2.2 (P= .388), the amplitudes were 54.2+/-22.4 and 52.7+/-17.4 (P=.737), and the area under the reflex curve were 188.0+/-151.1 and 163.2+/-134.3 (P=.443). All parameters of the RAIR, except the amplitude were significantly diminished in incontinent patients whether they had a sphincter defect or not. CONSLUSIONS: Although the RAIR functions against continence in normal conditions by inhibiting sphincteric tone, it behaves suitably for keeping continence in the presence of incontinence, whatever the cause is, by attenuating the degree of inhibition.

A Case of Cytomegalovirus Enterocolitis and Jejunal Perforation During Immune Reconstitution with Highly Active Antiretroviral Treatment

Immune reconstitution syndrome (IRS) in HIV-infected patients is an adverse consequence of the restoration of pathogen-specific immune responses during the initial months of highly active antiretroviral treatment(HAART). Previously subclinical infections are unmasked or pre-existing opportunistic infections clinically deteriorate as host immunopathological inflammatory responses are switched on. While the eye is the area where Cytomegalovirus(CMV)-associated IRS occurs most often in patients with AIDS, it also can present with intestinal or pulmonary involvement. We present a case report of an HIV-infected patient in whom CMV enterocolitis and jejunal perforation developed after HAART.

A Case of Cytomegalovirus Enterocolitis and Jejunal Perforation During Immune Reconstitution with Highly Active Antiretroviral Treatment

Immune reconstitution syndrome (IRS) in HIV-infected patients is an adverse consequence of the restoration of pathogen-specific immune responses during the initial months of highly active antiretroviral treatment(HAART). Previously subclinical infections are unmasked or pre-existing opportunistic infections clinically deteriorate as host immunopathological inflammatory responses are switched on. While the eye is the area where Cytomegalovirus(CMV)-associated IRS occurs most often in patients with AIDS, it also can present with intestinal or pulmonary involvement. We present a case report of an HIV-infected patient in whom CMV enterocolitis and jejunal perforation developed after HAART.

Operative Treatment of the Colonic Diverticular Disease

PURPOSE: In recent years, colonic diverticular disease has increased rapidly because of high intraluminal pressure in the colon due to the low fiber westernized diet and the increasing number of elderly people. Furthermore, emergency operation is required in many cases. Therefore, the aim of this study is proposed to review the optimal treatment guide. METHODS: This study is a retrospective review of the hospital records of 34 patients who underwent surgical treatment for colonic diverticular diseases at the National Medical Center from March 1992 to July 2003. RESULTS: The patients consisted of 23 males and 11 females, with mean age of 49 years. The lesion sites were cecum (62%), sigmoid colon (20%), ascending colon (9%), transverse colon (6%) and descending colon (3%), in descending orders of frequency. The patients were staged by Thorsen classification at the right colon and by Hinchey classification at the other sites. At the right colon, there were no cases of stage IV and 2 of bleeding. At the transverse colon and left colon, there were 3 cases of stage II, 5 of III, and 2 of IV. For the right colon, all patients underwent one- stage operation. For the other sites, 3 one- stage operations and 7 two- stage operations were performed. Major or minor postoperative complications occurred in 12 patients, including 2 mortality cases. Among them, 2 cases with colocutaneous fistulas might have been prevented if the operation had been made on the basis of stage. CONCLUSION: Because diverticular disease occurs at the various sites of the colon and has potential risk, it is important that patient treatment is based on stage.

Comparison of Laparoscopic Cholecystectomies between the Two 5-year Intervals

PURPOSE: The laparoscopic cholecystectomy has become a common procedure for treating gallbladder disease. The objectives of this study was to evaluate the learning curve by reviewing 145 patients treated with laparoscopic cholecystectomy, between Group A (From January 1991 to December 1995) and Group B (From January 1996 to December 2000). METHODS: We retrospectively analyzed 145 laparoscopic cholecystectomies performed at the Department of General Surgery, National Medical Center, from January 1991 to December 2000. The sex, age, operation time, associated disease, previous operation history, hospital stay, and pathology were reviewed. RESULTS: The ratio of Females to males was 1.9:1, and their age ranged from 18 to 80 years with the majority in their fifties and sixties. Most of the operative indications were cholelithiasis. The mean operative time was 89 minutes, which varied between 40 and 180 minutes, and the average admission time was five days. The operation times of Group A and Group B were statistically significant with respect to learning curve (p value<0.000). A linear regression test of the operation time and operation cases was also significant. The postoperative analgesic injection and hospital stay were improved in Group B, but had no statistical significance. A conversion to open cholecystectomy was done in four cases due to bleeding, severe adhesion, or clip migration of the cystic duct during surgery. CONCLUSION: The laparoscopic cholecystectomy was a safe and effective treatment for gallbladder disease, and wepredict that the operation time will become shorter with more experience.

Whole grain consumption reduces insulin demand, lipid peroxidation and plasma homocysteine concentrations in patients with coronary artery disease

BACKGROUND: Although current dietary guidelines recommend to increase the consumption of whole grain, these recommendations are mainly derived from the belief that replacing fats with carbohydrate may reduce risk of coronary artery disease (CAD) by improving serum lipids. Our objective was to evaluate whether the isocalorical replacement of refined rice with whole grain reduce CAD risk factors such as insulin demand and lipid peroxidation in CAD patients. METHODS: Thirty-eight male patients with CAD were provided with 70 g powder of whole grain (220 kcal) for 16 weeks, replacing cooked refined rice as a carbohydrate source of breakfast. An oral glucose tolerance test (OGTT) was performed in all subjects to determine the effect of whole grain consumption on serum concentrations of insulin and glucose in CAD patients with different degree of glucose tolerance. RESULTS: With the substitution of whole grain for refined rice, serum glucose concentrations decreased by 24% without altering body weight and energy intake. Estimates of daily fiber and vitamin E intakes increased by 24% and 50%, respectively. Whole grain consumption in CAD patients without diabetes decreased fasting glucose (22%) and the area under the curve (AUC) for insulin (26%) and glucose (19%) during an OGTT. CAD patients with diabetes also showed reductions in fasting glucose (27%) and AUC for glucose (25%) during the OGTT, compared with baseline values. Whole grain consumption reduced plasma malondialdehyde and homocysteine and urinary 8-epi-prostaglandin F 2alpha concentrations by about 30%. Lipid-corrected concentrations of alpha-carotene, retinol, alpha- and gamma-tocopherol and lycopene increased by 22-46%, compared with baseline values. Whole grain consumption decreased the percentage composition of w6 fatty acids of serum phospholipid increased by 14%. CONCLUSION: The replacement of refined rice with whole grain as a carbohydrate source of a meal showed significant beneficial effects on glucose, insulin and homocysteine concentrations and lipid peroxidation in CAD patients. These effects are likely to substantially reduce the risk factors of CAD and diabetes in CAD patients.

Small-Bowel Obstruction in Patients with a Previous History of Abdominal Surgery due to Cancer

PURPOSE: The purpose of this study was to analyze the clinical features and to assess the risk factors in the treatment of small-bowel obstructions. METHODS: This retrospective clinical report was based on the medical records of 67 patients who were treated between Jan. 1992 and Dec. 1999 and who had had a history of abdominal surgery due to cancer. RESULTS: The distribution of primary cancer was as follows: stomach cancer 36 (53.7%), colorectal cancer 25 (37.3%), uterine and ovarian cancer 4 (6.0%), and other cancers 2 (3.0%). The mean interval from the primary operation to the development of a small- bowel obstruction was 27 months. Conservative treatment produced a successful outcome in 36 patients (59.0%), but recurrences of obstruction were noted in 18 of those patients. There were 34 operations in 30 patients. The initial success rate of operative treatment was 80% (24/30), obstructions recurred in 6 patients. The causes of obstructions in the surgically treated patients were adhesion (53.3%) and recurrence of cancer (46.7%). The postoperative complication rate was 44.1%, and the mortality rate was 20.0%. The mean survival time of the patients with benign causes of obstruction was significantly longer than that of the patients with malignant causes of obstruction (46 months vs 11 months). CONCLUSION: In the treatment of such patients, conservative treatment should be considered first. However if conservative treatment fails, surgery should be done without hesitation, especially in patients with no definite evidence of recurrence.

Clinical Significance of Lymph Node Micrometastasis in Dukes' Stage A&B Colorectal Cancer: An Immunohistochemical Study

PURPOSE: Lymph node metastasis is the most important prognostic factor in colorectal cancer. However, 20~30% of patients with lymph node negative colorectal cancer die of recurrent disease. We investigated whether the detection of micrometastasis is of any clinical significance in Dukes' stage A & B colorectal cancer. METHODS: Ninety patients who underwent curative resection of colorectal cancer from Aug. of 1996 to Jan. of 1999 were entered the study. For examination, we used paraffin blocks of lymph nodes which were metastasis-free by conventional histopathology. After preparation of tissue blocks using the serial sectioning technique, the specimens were stained with immunohistochemical method using anticytokeratin antibody. And the hematoxylin-eosin staining was repeated. RESULTS: We disclosed micrometastases in 15 of 90 cases, mostly located in subcapsular sinuses. And in 8 of 15 cases, we also found metastases in repeated H&E staining. There were no significant relationship between the detection of micrometastases and the depth of wall invasion, the histological grade and the status of lymphovascular invasion. With median follow-up of 15 months, we found no significant difference in recurrence between the micrometasis positive and negative groups. CONCLUSIONS: The result showed that the micrometastasis of lymph node in colorectal caner might increase the risk for development of tumor recurrence. But because of small numbers of recurrent cases and relatively short follow-up period, there was no statistically significant relationship between micrometastasis negative and positive groups.