A clinicopathologic and immunohistochemical study of fifty‐two primary carcinomas of the small intestine (20 duodenal, 18 jejunal, and 14 ileal) was performed. Most of these neoplasms were located in the proximal duodenum, proximal... more
A clinicopathologic and immunohistochemical study of fifty‐two primary carcinomas of the small intestine (20 duodenal, 18 jejunal, and 14 ileal) was performed. Most of these neoplasms were located in the proximal duodenum, proximal jejunum, and distal ileum. Most of these tumors produced both sialomucin and sulfomucin, although the adjacent mucosa showed hyperplastic changes with increased sialomucin secretion. Argyrophil cells were recognized in seven duodenal (35%), 13 jejunal (72%), and nine ileal (69%) carcinomas. Eighteen of the 29 tumors showing positive argyrophil reactions also had argentaffin cells. The common features of mucins and endocrine cells in these tumors suggest the multipotency of small intestinal carcinoma. The prognosis correlated with the histologic type, carcino‐embryonic antigen (CEA) grading, invading pattern of tumor margins, and vascular permeation and regional lymph node metastasis.
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Dental plaque has been suggested as a permanent reservoir of Helicobacter pylori (H. pylori) and a potential source of reinfection. The aims of this study were to investigate the presence of H. pylori in both dental plaque and the stomach... more
Dental plaque has been suggested as a permanent reservoir of Helicobacter pylori (H. pylori) and a potential source of reinfection. The aims of this study were to investigate the presence of H. pylori in both dental plaque and the stomach and to evaluate the therapeutic effect of triple therapy on H. pylori in dental plaque. Dental plaque and gastric biopsy samples were obtained from 65 patients with dyspeptic symptoms for endoscopic examination. The prevalence of H. pylori in dental plaque and stomach was determined with rapid urease test, histologic examinations and polymerase chain reaction assay based on the primer pair derived from the cagA gene of H. pylori. Triple therapy was administered to patients infected with H. pylori. H. pylori status was re-evaluated after eradication therapy. Prior to treatment, H. pylori was found in the stomach in 38 of 65 (58%) patients and in dental plaque in 28 of 65 (43%) patients. The coexisting infection rate of H. pylori in both stomach and ...
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Deformity of duodenal bulb, gastric metaplasia of duodenal
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BACKGROUND AND PURPOSE Anti-Helicobacter pylori triple therapy is effective for healing duodenal ulcer (DU) diseases and reducing disease recurrence. However, multifocal duodenal erosions or shallow ulcers may develop after triple... more
BACKGROUND AND PURPOSE Anti-Helicobacter pylori triple therapy is effective for healing duodenal ulcer (DU) diseases and reducing disease recurrence. However, multifocal duodenal erosions or shallow ulcers may develop after triple therapy. The purpose of this study was to investigate the incidence and outcome of duodenal erosions that developed after triple therapy. METHODS A total of 106 Taiwanese with active DU and with H. pylori infection were enrolled in this study. All patients received anti-H. pylori triple therapy (i.e., 2 weeks of antimicrobial agents combined with treatment for 4 to 6 weeks with acid suppression agents). Follow-up endoscopy was performed immediately after stopping treatment. The incidence of multifocal erosions or shallow ulcers over the bulb and/or second portion of the duodenum was studied. Additional acid suppression agent was given for 4 weeks whenever duodenal erosions or shallow ulcers were found. RESULTS Out of 106 patients, 11 (10.4%) were found to ...
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We developed a magnetic-assisted capsule colonoscope system with integration of computer vision-based object detection and an alignment control scheme. Two convolutional neural network models A and B for lumen identification were trained... more
We developed a magnetic-assisted capsule colonoscope system with integration of computer vision-based object detection and an alignment control scheme. Two convolutional neural network models A and B for lumen identification were trained on an endoscopic dataset of 9080 images. In the lumen alignment experiment, models C and D used a simulated dataset of 8414 images. The models were evaluated using validation indexes for recall (R), precision (P), mean average precision (mAP), and F1 score. Predictive performance was evaluated with the area under the P-R curve. Adjustments of pitch and yaw angles and alignment control time were analyzed in the alignment experiment. Model D had the best predictive performance. Its R, P, mAP, and F1 score were 0.964, 0.961, 0.961, and 0.963, respectively, when the area of overlap/area of union was at 0.3. In the lumen alignment experiment, the mean degrees of adjustment for yaw and pitch in 160 trials were 21.70° and 13.78°, respectively. Mean alignme...
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Hookworms usually reside in the small intestine, so they are rarely discovered during routine upper gastrointestinal endoscopy (UGIE). We herein report two cases of hookworm infestation diagnosed by UGIE. One of the two cases combined... more
Hookworms usually reside in the small intestine, so they are rarely discovered during routine upper gastrointestinal endoscopy (UGIE). We herein report two cases of hookworm infestation diagnosed by UGIE. One of the two cases combined with gastric adenocarcinoma and no parasite ova was detected in stool examination. Ancylostoma duodenale and Necator americanus can infect humans. In Taiwan, N. americanus is prevalent in the north and the east, and A. duodenale is prevalent in the south and the central region. The infection rate in Taiwan is less than 1%. The adult hookworm resides mainly in the jejunum and may be refluxed toward the duodenum and the stomach during bowel contraction. Endoscopically, hookworms are shining red in color, about 10mm in length, and a couple of female and male worms usually hug together tightly. There is no report to suggest the relation between hookworm infestation and gastric malignancy in the literature.
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Gallstone ileus is an uncommon mechanical bowel obstruction caused by impaction of one or more gallstones in the intestine. The ileum is involved in about 80% of cases. Difficult and delayed diagnosis and old age of the patients account... more
Gallstone ileus is an uncommon mechanical bowel obstruction caused by impaction of one or more gallstones in the intestine. The ileum is involved in about 80% of cases. Difficult and delayed diagnosis and old age of the patients account for its high mortality. We herein report one case with gallstone ileus diagnosed by ultrasound preoperatively in which the patient survived after surgery with only a few complications related to the patient's debilitated medical problems. Emphasis is also put upon how to deal with acute abdomen in elderly patients; in addition to traditional roentgenography, ultrasound may afford a tool to detect gallstone ileus.
Upon routine sonographic examination, some patients with chronic hepatitis B were found to have a larger gallbladder. In order to evaluate their gallbladder size and contractility, 45patients with chronic hepatitis B, along with 45... more
Upon routine sonographic examination, some patients with chronic hepatitis B were found to have a larger gallbladder. In order to evaluate their gallbladder size and contractility, 45patients with chronic hepatitis B, along with 45 healthy subjects as control, were entered into this study. All 90 subjects were free from factors affecting gallbladder contractility. After overnight fasting, the gallbladder cross-section area was measured by planimetry of real-time sonographic unit. The postprandial gallbladder area was measured by the same method at 30 and 45 minutes. The results showed that the fasting gallbladder size was significantly larger in the patients with chronic hepatitis than in the control group (p＜0.0l). No significant difference of the contractility between these two groups was noted at 30 and 45 minutes after taking a fatty meal, although the gallbladder area decreased significantly with time in both groups (p＜0.001). It seems reasonable to conclude that patietns with ...
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In this article, we propose a method for locating a magnetic capsule endoscope, which is utilized to observe the gastrointestinal tract, especially for colon. Recent studies mainly focus on either single-magnet positioning or multiple... more
In this article, we propose a method for locating a magnetic capsule endoscope, which is utilized to observe the gastrointestinal tract, especially for colon. Recent studies mainly focus on either single-magnet positioning or multiple magnets positioning with similar scale in magnetic parameters, whereas these methods cannot be directly applied to the proposed magnetic-assisted capsule endoscope system, in which two magnets with big differences in magnetic parameters are used. An algorithm based on the Levenberg–Marquardt algorithm and a Hall sensor array is presented to solve this problem. Three different experiments have been carried out to validate the feasibility and effectiveness of the proposed method for the magnetic capsule positioning and orientation.
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This paper presents an autonomous navigation system for cost-effective magnetic-assisted colonoscopy, employing force-based sensors, an actuator, a proportional–integrator controller and a real-time heuristic searching method. The force... more
This paper presents an autonomous navigation system for cost-effective magnetic-assisted colonoscopy, employing force-based sensors, an actuator, a proportional–integrator controller and a real-time heuristic searching method. The force sensing system uses load cells installed between the robotic arm and external permanent magnets to derive attractive force data as the basis for real-time surgical safety monitoring and tracking information to navigate the disposable magnetic colonoscope. The average tracking accuracy on magnetic field navigator (MFN) platform in x-axis and y-axis are 1.14 ± 0.59 mm and 1.61 ± 0.45 mm, respectively, presented in mean error ± standard deviation. The average detectable radius of the tracking system is 15 cm. Three simulations of path planning algorithms are presented and the learning real-time A* (LRTA*) algorithm with our proposed directional heuristic evaluation design has the best performance. It takes 75 steps to complete the traveling in unknown s...
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Although traditional chemotherapy kills a fraction of tumor cells, it also activates the stroma and can promote the growth and survival of residual cancer cells to foster tumor recurrence and metastasis. Accordingly, overcoming the host... more
Although traditional chemotherapy kills a fraction of tumor cells, it also activates the stroma and can promote the growth and survival of residual cancer cells to foster tumor recurrence and metastasis. Accordingly, overcoming the host response induced by chemotherapy could substantially improve therapeutic outcome and patient survival. In this study, resistance to treatment and metastasis has been attributed to expansion of stem-like tumor-initiating cells (TICs). Molecular analysis of the tumor stroma in neoadjuvant chemotherapy-treated human desmoplastic cancers and orthotopic tumor xenografts revealed that traditional maximum-tolerated dose chemotherapy, regardless of the agents used, induces persistent STAT-1 and NF-κB activity in carcinoma-associated fibroblasts. This induction results in the expression and secretion of ELR motif-positive (ELR(+)) chemokines, which signal through CXCR-2 on carcinoma cells to trigger their phenotypic conversion into TICs and promote their inva...
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The relationship between histological maturity of healed duodenal ulcers and ulcer recurrence after 6 weeks of treatment with colloidal bismuth subcitrate or cimetidine was investigated. There was no significant difference in healing... more
The relationship between histological maturity of healed duodenal ulcers and ulcer recurrence after 6 weeks of treatment with colloidal bismuth subcitrate or cimetidine was investigated. There was no significant difference in healing rates between colloidal bismuth subcitrate- and cimetidine-treated patients (85.7% and 71.8%, respectively; P greater than 0.05). Histologically, the regenerating mucosa of healed ulcers was divided into three categories--good, fair, and poor--according to pattern. Sixty percent of healed colloidal bismuth subcitrate-treated and 30.9% of healed cimetidine-treated ulcers had a good pattern; the difference was statistically significant (P = 0.027). The difference in recurrence rates between healed colloidal bismuth subcitrate-treated and healed cimetidine-treated patients was statistically significant at 3 months (3.45% and 20%, respectively; P = 0.044). All recurrent ulcers in both groups had fair or poor patterns of regenerating mucosa. It was concluded that the greater histological maturity of the regenerating mucosa may contribute to the lower recurrence rate in colloidal bismuth subcitrate-treated patients than in cimetidine-treated patients.
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Colon cancer is the third most common malignancy worldwide. Recently, some interesting associations between ghrelin and cancer were reported, and it may participate in colon cancer development. In the present report, we explored the role... more
Colon cancer is the third most common malignancy worldwide. Recently, some interesting associations between ghrelin and cancer were reported, and it may participate in colon cancer development. In the present report, we explored the role of the growth hormone secretagogue receptor (GHS-R), Ras, phosphatidylinositol 3-kinase (PI3K), Akt, and mammalian target of rapamycin (mTOR) pathways in the ghrelin-induced proliferation of human colon cancer cells. Ghrelin-caused HT-29 proliferation was reduced by [D-Lys3]-GHRP-6 (a GHS-R inhibitor). We also found that a dominant negative mutant of Ras (Ras DN), a PI3K inhibitor (LY 294002), an Akt DN, and an mTOR inhibitor (rapamycin) attenuated ghrelin-caused colon cancer cell proliferation. We found that ghrelin induced time-dependent increases in Ras activity. Moreover, ghrelin-mediated Akt Ser473 phosphorylation was attenuated by a Ras DN and LY 294002. Furthermore, a Ras DN, LY 294002, and an Akt DN all inhibited ghrelin-caused mTOR Ser2448 ...
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Abstract In this paper, a capsule endoscope which has both 2 optical image modules (lenses and CMOS sensors) and actively controllable locomotion function is presented. The two optical image modules are placed in the opposite ends of the... more
Abstract In this paper, a capsule endoscope which has both 2 optical image modules (lenses and CMOS sensors) and actively controllable locomotion function is presented. The two optical image modules are placed in the opposite ends of the capsule. The locomotion ...
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To investigate the effectiveness of 4 d' anti-Helicobacter pylori therapy on the H pylori-infected Mongolian gerbils based on physiological and pathological changes. We used 6-wk-old male gerbils... more
To investigate the effectiveness of 4 d' anti-Helicobacter pylori therapy on the H pylori-infected Mongolian gerbils based on physiological and pathological changes. We used 6-wk-old male gerbils orally inoculated with H pylori (ATCC43504, 2X10(8) CFU/mL). Seven weeks after H pylori inoculation, the animals of study group received 4 d' anti-H pylori triple therapy (H pylori-eradicated group). Seven days later, all animals of the H pylori-eradicated and control groups (H pylori-infected and H pylori-uninfected groups) were sacrificed. We examined gastric mucosal lesions macroscopically, studied gastritis microscopically and determined the stomach weight ratio, myeloperoxidase (MPO) activity and prostaglandin (PG) E(2) level. The results showed that both macroscopic and histological gastric damages were significantly less in H pylori-eradicated group than H pylori-infected group. Stomach weight ratio, MPO activity and PGE(2) levels were significantly higher in H pylori-infected group than those in the other two groups. Four days' anti-H pylori therapy was effective in the improvement of H pylori-induced gastric lesions in Mongolian gerbils.
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Previous report showed that epidermal growth factor (EGF) promotes tumor progression. Several studies demonstrated that growth factors can induce heme oxygenase (HO)-1 expression, protect against cellular injury and cancer cell... more
Previous report showed that epidermal growth factor (EGF) promotes tumor progression. Several studies demonstrated that growth factors can induce heme oxygenase (HO)-1 expression, protect against cellular injury and cancer cell proliferation. In this study, we investigated the involvement of the c-Src, NADPH oxidase, reactive oxygen species (ROS), PI3K/Akt, and NF-κB signaling pathways in EGF-induced HO-1 expression in human HT-29 colon cancer cells. Treatment of HT-29 cells with EGF caused HO-1 to be expressed in concentration- and time-dependent manners. Treatment of HT-29 cells with AG1478 (an EGF receptor (EGFR) inhibitor), small interfering RNA of EGFR (EGFR siRNA), a dominant negative mutant of c-Src (c-Src DN), DPI (an NADPH oxidase inhibitor), glutathione (an ROS inhibitor), LY294002 (a PI3K inhibitor), and an Akt DN inhibited EGF-induced HO-1 expression. Stimulation of cells with EGF caused an increase in c-Src phosphorylation at Tyr406 in a time-dependent manner. Treatment...
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Dental plaque has been suggested as a permanent reservoir of Helicobacter pylori (H. pylori) and a potential source of reinfection. The aims of this study were to investigate the presence of H. pylori in both dental plaque and the stomach... more
Dental plaque has been suggested as a permanent reservoir of Helicobacter pylori (H. pylori) and a potential source of reinfection. The aims of this study were to investigate the presence of H. pylori in both dental plaque and the stomach and to evaluate the therapeutic effect of triple therapy on H. pylori in dental plaque. Dental plaque and gastric biopsy samples were obtained from 65 patients with dyspeptic symptoms for endoscopic examination. The prevalence of H. pylori in dental plaque and stomach was determined with rapid urease test, histologic examinations and polymerase chain reaction assay based on the primer pair derived from the cagA gene of H. pylori. Triple therapy was administered to patients infected with H. pylori. H. pylori status was re-evaluated after eradication therapy. Prior to treatment, H. pylori was found in the stomach in 38 of 65 (58%) patients and in dental plaque in 28 of 65 (43%) patients. The coexisting infection rate of H. pylori in both stomach and ...
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heart failure Yu-Hsun Kao , Gi-Shih Lien , Tze-Fan Chao , Yi-Jen Chen b,e,⁎ a Department of Medical Education and Research, Wan Fang Hospital, Taipei Medical University, Taipei, Taiwan b Graduate Institute of Clinical Medicine, College of... more
heart failure Yu-Hsun Kao , Gi-Shih Lien , Tze-Fan Chao , Yi-Jen Chen b,e,⁎ a Department of Medical Education and Research, Wan Fang Hospital, Taipei Medical University, Taipei, Taiwan b Graduate Institute of Clinical Medicine, College of Medicine, Taipei Medical University, Taipei, Taiwan c Division of Gastroenterology, Department of Internal Medicine, Wan Fang Hospital, Taipei Medical University, Taipei, Taiwan d Division of Cardiology and Cardiovascular Research Center, Veterans General Hospital, Taipei, Taiwan e Division of Cardiovascular Medicine, Department of Internal Medicine, Wan Fang Hospital, Taipei, Taipei Medical University, Taipei, Taiwan
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Cardiovascular disease is the leading cause of morbidity and mortality in patients with diabetes mellitus (DM), and patients with DM frequently develop diabetic cardiomyopathy. Currently, effective treatments for diabetic cardiomyopathy... more
Cardiovascular disease is the leading cause of morbidity and mortality in patients with diabetes mellitus (DM), and patients with DM frequently develop diabetic cardiomyopathy. Currently, effective treatments for diabetic cardiomyopathy are limited. Vitamin D exerts pleiotropic effects on the cardiovascular system and is associated with DM. The purpose of this review was to evaluate published research on vitamin D in diabetic cardiomyopathy by searching PubMed databases. Herein, we reviewed vitamin D metabolism; evaluated the molecular, cellular, and neuroendocrine effects in native and bioactive vitamin D; and evaluated the role of vitamin D in treating cardiovascular disease and DM. Some evidence suggests that vitamin D may improve cardiovascular outcomes in diabetes through anti-inflammatory, antioxidative, antihypertrophic, antifibrotic, and antiatherosclerotic activities and by regulating advanced glycation end-product signaling, the renin-angiotensin system, and cardiac metabolism. This clinical and laboratory evidence suggests that vitamin D may be a potential agent in treating diabetic cardiomyopathy. However, using vitamin D entails possible adverse risks of hypercalcemia, hyperphosphatemia, and vascular calcifications. Therefore, future studies should be conducted that clarify the potential benefits of vitamin D through large-scale randomized clinical trials in well-defined groups of diabetic patients.
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ABSTRACT Background: Patients with cytomegalovirus (CMV) colitis have increasingly been recognized among critically ill patients, yet few specific clinical and endoscopic features are known. In this study, we investigated the common... more
ABSTRACT Background: Patients with cytomegalovirus (CMV) colitis have increasingly been recognized among critically ill patients, yet few specific clinical and endoscopic features are known. In this study, we investigated the common clinical and endoscopic features of CMV colitis in critically ill patients. Methods: From January 1, 2000 to February 28, 2014, patients with a histopathological diagnosis of CMV colitis were retrospectively reviewed. We reviewed and analyzed the clinical presentation, primary diseases, serum CMV antibody, treatment, mortality, and endoscopic features of these patients. Results: Eighteen patients were diagnosed as having CMV colitis and 15 CMV colitis patients were included in this study. The mean age was 65.7 years (range 42-92 years). Bloody diarrhea and persistent diarrhea were the most common initial presentations of CMV, and sepsis was the most common comorbidity found. CMV-IgM was positive in three (17%) patients, and CMV-IgG was positive in 14 (93.3%) patients. All patients received ganciclovir and 11 patients clinically improved. Four (26.6%) patients died and two patients had colon perforation. According to the severity of the diseases, endoscopic presentation of CMV colitis ranged from colonic mucosa edema, loss of vasculature, subepithelial hemorrhage, and circular or geographic ulcers to perforation. Ten (66.7%) patients had multiple ulcers and five (33.3%) patients had a single ulcer. Eleven (73.3%) patients had colitis involving distal to splenic flexure, and four (26.6%) patients had colitis involving the whole colon. Conclusion: Critically ill patients who present with bloody stool or persistent diarrhea should be considered for the diagnosis of CMV colitis. The endoscopic presentation of CMV colitis is highly variable. We suggest that the endoscopic manifestation of CMV colitis can be divided into three stages: nonulcerative inflammatory stage, simple ulcerative stage, and complicated ulcerative stage.
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ABSTRACT The Oriental Fruit Fly (OFF), Bactrocera dorsalis (Hendel), is one of most devastating insect pests that have periodically caused serious damage to fruit farms in Taiwan and many countries in the world. In the past, many studies... more
ABSTRACT The Oriental Fruit Fly (OFF), Bactrocera dorsalis (Hendel), is one of most devastating insect pests that have periodically caused serious damage to fruit farms in Taiwan and many countries in the world. In the past, many studies reported that the population dynamics of OFF was partially correlated to the weather and the historical population development of OFF in the field. By making the best use of modern info-communication technologies (ICTs), long-term pest population data and microclimate variables measured with uniquely fine spatiotemporal resolution are now available to reveal the population dynamics of OFF. An analysis of data over three years using the Vector Auto-Regressive and Moving-Average model with eXogenous variables (VARMAX) was proposed to unravel the regulatory mechanism between the population dynamics of OFF and microclimate factors. In addition, the proposed model provides a 7-day forecast for population dynamics of OFF. The accuracy of 7-day risk level forecasting yielded by the proposed model ranges from 0.87 to 0.97, and the average root-mean squared errors of forecasting the population dynamics fall in the interval between 0.31 and 4.95 per day per farm. The proposed forecasting model can allow authorities to gain a better understanding of the dynamics of OFF and anticipate pest-related problems, so they can make preemptive and effective pest management decisions before the real problems occur.
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Colonoscopy is considered the most effective method for diagnosing colorectal diseases, but its application is sometimes limited due to invasiveness, patient intolerance, and the need for sedation. The aim of this study was to improve the... more
Colonoscopy is considered the most effective method for diagnosing colorectal diseases, but its application is sometimes limited due to invasiveness, patient intolerance, and the need for sedation. The aim of this study was to improve the problem of loop formation and shorten the cecal intubation time of colonoscopy by using a magnetic control system (MCS). Two experienced gastroenterologists, three trainees, and a novice repeated colonoscopy without or with MCS on three colonoscopy training model simulator cases. These cases were divided into introductory (case 2) and challenging levels (cases 4 and 5). The cecal intubation times were recorded. For all cases, the average cecal intubation times for the experienced gastroenterologists with MCS were significantly shorter than without MCS (case 2: 52.45 vs. 27.65 s, p < 0.001; case 4: 166.7 vs. 120.55 s, p < 0.01; case 5: 130.35 vs. 100.2 s, p < 0.05). Those of the trainees also revealed significantly shorter times with MCS (case 2: 67.27 vs. 51 s, p < 0.01; case 4: 253.27 vs. 170.97 s, p < 0.001; case 5: 144.1 vs. 85.57 s, p < 0.001). Conducting colonoscopy with MCS is safe and smooth, and shortens the cecal intubation time by navigating the forepart of the colonoscope. In addition, all diagnostic and therapeutic benefits of conventional colonoscopy are retained.
Research Interests: Humans, Female, Male, Colonoscopy, Clinical Sciences, and 4 moreMiddle Aged, Magnets, Time Factors, and Colonoscopes
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Stevioside is a sweet-tasting glycoside isolated from the leaves of Stevia rebaudiana. It has been used as a noncaloric sugar substitute in Japan and Brazil for decades. Previous studies have shown that it lowered blood pressure in... more
Stevioside is a sweet-tasting glycoside isolated from the leaves of Stevia rebaudiana. It has been used as a noncaloric sugar substitute in Japan and Brazil for decades. Previous studies have shown that it lowered blood pressure in spontaneously hypertensive rats by intravenous injection. This study was designed to evaluate the hypotensive effect of stevioside in dogs and to define the underlying mechanism. After nasogastric administration of stevioside powder (200 mg/kg), the blood pressure of healthy mongrel dogs began to significantly decrease at 60 min and returned to baseline level at 180 min. The reduction of blood pressure was more rapid (at 5-10 min) and effective after intravenous injection. However, no significant change of blood pressure was noted after injection through left vertebral artery, implicating that the hypotensive effect is not related to the central nervous system. Stevioside also showed significant hypotensive effects in renal hypertensive dogs, in a dose-dependent manner. In cultured rat aortic smooth muscle cells (A7r5 cell line), stevioside can dose-dependently inhibit the stimulatory effects of vasopressin and phenylephrine on intracellular Ca(2+) in a calcium-containing medium. However, no intracellular Ca(2+) inhibitory effect was observed in calcium-free medium, implicating that stevioside may inhibit the Ca(2+) influx from extracellular fluid. Our present data show that stevioside did not influence the calcium ionophore (A23187) induced Ca(2+) influx, indicating that the antagonistic effect was through Ca(2+) channels. This study confirmed that stevioside is an effective antihypertensive natural product, and its hypotensive mechanism may be probably due to inhibition of the Ca(2+) influx.
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Three men and one woman with delayed posttraumatic ischemic stricture of the small intestine were studied, clinicopathologically. Three sustained trauma in traffic accidents, and the other one was injured at a workshop. The chief signs... more
Three men and one woman with delayed posttraumatic ischemic stricture of the small intestine were studied, clinicopathologically. Three sustained trauma in traffic accidents, and the other one was injured at a workshop. The chief signs and symptoms were repeatedly occurring incomplete intestinal obstruction. The interval between operation and trauma ranged from 1.5 to 14 months, with a mean of 4 months. The lesions were present in the jejunum 150 cm distant from the ligament of Treitz in one, and in the terminal ileum in three. Shallow ulcers, transmural inflammation, fibromusculosis, and neovascularity in the submucosa, as well as siderophages and foreign body reaction in the subserosa were evident, microscopically. The associated deeper ulcers proximal to the strictures in three were considered to have been induced by ischemic plus mechanical factors.
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Oxidative stress or excessive antioxidant levels-caused redox imbalance can alter apoptotic responses, and N-acetyl-L-cysteine (NAC) was able to inhibit H2 O2 -mediated cell death, but unable to prevent apoptosis induced by other... more
Oxidative stress or excessive antioxidant levels-caused redox imbalance can alter apoptotic responses, and N-acetyl-L-cysteine (NAC) was able to inhibit H2 O2 -mediated cell death, but unable to prevent apoptosis induced by other chemicals such as etoposide. We now demonstrate that 10 and 20 mM NAC, non-toxic concentrations, can enhance fisetin (FIS)-mediated apoptosis in colon cancer cells COLO205. Compared to treatment with FIS alone, combination treatment with NAC increased the expression of cleaved caspase-3 and PAPR protein, and produced greater density of DNA ladders. NAC reduced the mitochondrial membrane potential of FIS-treated COLO205 cells with induction of caspase 9 protein cleavage. DNA ladders induced by FIS + NAC were diminished by adding the caspase 3 inhibitor, DEVD-FMK, and the caspase 9 inhibitor, YVAD-FMK. Combinatorial treatment COLO205 cells with NAC and FIS showed potent inhibition on ERK protein phosphorylation, compared with those from FIS or NAC-treated groups by Western blotting using specific antibodies. Addition of the chemical ERK inhibitors, PD98059 and U0126, significantly inhibited ERK protein phosphorylation, accompanied by induced DNA ladder formation, cleavage of caspase 3 and PARP protein in COLO205 cells. Furthermore, NAC showed an enhancement on a FIS-related chemical chrysin-induced apoptosis of COLO205 cells, and NAC sensitization of colon cancer cells to FIS-induced apoptosis was also identify in colonic cancer cells HCT-116, HT-29, and HCT-15 cells. The evidence to support NAC sensitizing human colon cancer cells to FIS-induced apoptosis was provided, and application of NAC and FIS as a strategy to treat colonic cancer deserved for further in vivo study.
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Two patients with primary malignant lymphoma underwent spontaneous regression. One was a 40-year-old woman with a large ulcerating tumor on the greater curvature of the gastric antrum. This tumor shrank spontaneously, leaving only a small... more
Two patients with primary malignant lymphoma underwent spontaneous regression. One was a 40-year-old woman with a large ulcerating tumor on the greater curvature of the gastric antrum. This tumor shrank spontaneously, leaving only a small shallow ulcer. The resected specimen showed a minute focus of malignant lymphoma in the ulcer base. The other was a 73-year-old man who had a tumor with central ulceration on the posterior wall of the gastric antrum. Endoscopic biopsy revealed a malignant lymphoma. This tumor disappeared 60 days later. The patient refused surgery and remains well with no evidence of recurrent disease at this writing, 44 months later. Although there have been several case reports of spontaneous regression, partial or complete, of gastric malignant lymphoma, our cases seem to be the ones best proven.
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An 81-year-old woman had an early carcinoma invading focally into the upper submucosa of the middle-transverse colon, which was accompanied by extensive lymph node metastases and resulted in a poor prognosis. Although her tumor was small... more
An 81-year-old woman had an early carcinoma invading focally into the upper submucosa of the middle-transverse colon, which was accompanied by extensive lymph node metastases and resulted in a poor prognosis. Although her tumor was small and flat, a rim of pale yellow-speckled mucosa adjacent to the tumor enabled its earlier detection. To further study the exceptional lymph node metastases we studied the expression of intestinal trefoil factor and sialyl Tn antigen immunohistochemically on the resected specimen. Their simultaneous expression in lymph node metastasis further supports the aggressive nature of this tumor.