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Biomedical subjects

M Hashizume

Publications and source records attributed to M Hashizume.

At least 37 records · Page 2Linked to original sources

Early experiences of endoscopic procedures in general surgery assisted by a computer-enhanced surgical system.

We performed a variety of complete total endoscopic general surgical procedures, including colon resection, distal gastrectomy, and splenectomy, successfully with the assistance of the da Vinci computer-enhanced surgical system. The robotic system allowed us to manipulate the endoscopic instruments as effectively as during open surgery. It enhanced visualization of both the operative field and precision of the necessary techniques, as well as being less stressful for the endoscopic operating team. This technological innovation can therefore help surgeons overcome many of the difficulties associated with the endoscopic approach and thus has the potential to enable more precise, safer, and more minimally invasive surgery in the future.

Adult↗

Extremely high prevalence of hypercalciuria in children living in the Aral Sea region.

UNLABELLED: The Aral Sea region is a natural area seriously polluted by human activities. In addition to the increased prevalence of diverse chronic diseases in children, the risk of developing urolithiasis is reported to be high in this region. This study was undertaken to clarify the prevalence of hypercalciuria in children of the Aral Sea region. A group of 205 children living in Kazalinsk, close to the Aral Sea, and a group of 187 children living in Zhanakorgan, far from the Aral Sea, were screened for hypercalciuria. Urinary sodium excretion (sodium per creatinine, uNa/Cr) in addition to calcium excretion (calcium per creatinine, uCa/Cr) was also calculated for each subject. Mean uCa/Cr (mmol/mmol) and uNa/Cr (mmol/mmol) excretions were significantly higher in Kazalinsk than in Zhanakorgan (uCa/Cr: 0.75 +/- 0.74 and 0.33 +/- 0.30; uNa/Cr: 3.54 +/- 2.27 and 2.89 +/- 1.69, respectively, mean +/- SD, p < 0.01). Hypercalciuria regarded as an uCa/Cr of more than 0.703 was observed in 79 out of 205 Kazalinsk children (38.6%) while this was seen in only 24 out of 187 Zhanakorgan children (12.8%). Linear regression analysis revealed a direct positive correlation between urinary calcium and sodium excretion (p < 0.01) in Kazalinsk children. CONCLUSION: The prevalence of hypercalciuria in children around the Aral Sea region is extremely high. This may be associated with excessive intake of calcium and sodium, or due to impaired renal tubular function caused by toxic chemicals. Therefore, hypercalciuria that may lead to urolithiasis should be taken into account when considering the health problems of this area.

Asia, Central↗

Beneficial effects of 3-dimensional visualization on hepatic vein reconstruction in living donor liver transplantation using right lobe graft.

BACKGROUND: Recently, virtual operation planning and navigation systems have been introduced in the field of neurosurgery and orthopedic surgery. We report here the beneficial effects of 3-dimensional (3D) visualization on hepatic venous reconstruction in living donor liver transplantation (LDLT) using right lobe graft. METHODS: 3D-image reconstruction of the liver was rendered with 3-mm slices of helical computed tomography (CT) data using zioM900 (Zio Software Inc., Tokyo, Japan). To understand the anatomy of the donor's vessels and design an operation plan, a picture of the vessels in and around the liver was reconstructed. RESULTS: The 3D image demonstrated two short hepatic veins next to the inferior right hepatic vein (IRHV) as well as a large IRHV. The 3D image showed a more precise diameter of the right hepatic vein (RHV) and the IRHV and a more accurate distance between the two hepatic veins than did images measured by 2-dimensional CT. This preoperative information allowed the donor surgeon to dissect the inferior vena cava (IVC) and hepatic veins with reduced blood loss because of reduced risk of injury to the blood vessels. The 3D image revealed that both the RHV and the IRHV branched off at the same angle from the cylindrical IVC. Preoperative planning based on this information secured smooth anastomosis. CONCLUSIONS: 3D visualization is useful for hepatic venous reconstruction of the recipient as well as for donor surgery in LDLT using right lobe graft.

Female↗

Laparoscopic hepatectomy for hepatocellular carcinoma.

BACKGROUND: No reports exist on the role of laparoscopic hepatectomy in the short- and long-term outcomes of patients with hepatocellular carcinoma (HCC). We present our results from using laparoscopic hepatectomy for HCC and discuss the importance of this procedure. METHODS: To investigate the role of laparoscopic hepatectomy in the short- and long-term outcomes, 17 patients with HCC who underwent laparoscopic hepatectomy (laparoscopic hepatectomy group) were compared with 38 patients who underwent conventional open hepatectomy (open hepatectomy group) during the same period. RESULTS: No differences in operation time, blood loss, rate of blood transfusion, or incidence of postoperative complications were found between the two groups. The postoperative hospital stay for the laparoscopic hepatectomy group was significantly shorter than for the open hepatectomy group. With long-term prognosis, no difference was found in survival rate and disease-free survival rate between the two groups. No recurrence was found in the stump of the remaining liver after laparoscopic hepatectomy. CONCLUSIONS: Laparoscopic hepatectomy has resulted in a better short-term outcome after surgery than conventional open hepatectomy. The long-term prognosis in the laparoscopic hepatectomy group was similar to that in the open hepatectomy group. Therefore, laparoscopic hepatectomy can be a new alternative for treatment of cirrhotic patients with HCC when patients are strictly selected.

Carcinoma, Hepatocellular↗

Endoscopic extirpation of benign breast tumors using an extramammary approach.

BACKGROUND: Skin incision has been made directly in the breast for treatment of benign breast tumor in spite of the young age of the patient population. METHODS: Small incisions (12 mm, 5 mm, and 2 mm) were made in the extramammary line, and the benign tumors (diagnosed by imaging and aspiration needle cytology) were endoscopically extirpated. RESULTS: The mean age of 36 patients was 27.6 years, and the mean mass size was 3.6 cm (7 masses at maximum). The average operation time per mass was 2.6 hours in the first 18 operations and 1.4 hours in the latter 19 operations. Overall blood loss was 19 mL. Postoperative complications were seen in 2 patients: an extended subcutaneous emphysema due to excessive CO2 gas inflation and a mild burn, both of which were reversible. All patients were extremely satisfied with the cosmetic results of the procedure. CONCLUSIONS: Endoscopic removal by the extramammary approach is the best option for benign breast tumors considering the patient's age and the excellent cosmetic results.

Adolescent↗

Immunohistochemical localization of vascular endothelial growth factor in the rat portal hypertensive gastropathy.

BACKGROUND AND AIMS: Portal hypertensive gastropathy (PHG) is now recognized to be a distinct entity. Recently, angiogenesis has been noticed as a key factor in clarifying the pathophysiology of various diseases. Angiogenesis in the PHT of explored gastric mucosa has yet to be explored. Vascular endothelial growth factor (VEGF) is a potent angiogenic factor. The aim of the present study was thus to investigate whether the hypoxic state exists in PHG, and whether VEGF appears more strongly in PHG than in normal gastric mucosa and, if so, what exactly is the role of the hypoxic state and VEGF in PHG. METHODS: At 1, 3, 7 and 14 days after either a portal ligation or sham operation, the portal venous pressure, the gastric mucosal blood flow volume and the blood gas were measured and, the expression of VEGF and antiproliferating cell nuclear antigen (PCNA) in gastric mucosal specimens was immunohistochemically assessed. RESULTS: The portal pressure (PP) and the gastric mucosal blood flow (GMBF) in the PHT rats were significantly greater than in the control (CTR). Both the SaO2 and PaO2 of the arterial blood gas were lower in the PHT rats than in the control rats. The percentage of VEGF expression in the PHG was found to be higher than that in the control gastric mucosa. The percentage of PCNA expression in the PHG was higher than that in the control gastric mucosa. CONCLUSION: The levels of SaO2 and PaO2 were lower in the PHT rats. There is a possibility that a kind of portal hypertensive gastric change may trigger an enhanced histochemical expression of VEGF. The increased activity of VEGF may have a possibility of the hypoxic gastric mucosal state caused by the presence of active congestion. This damaged mucosal state 'PHG' may thus facilitate the fragility in PHG and such lesions may be slow and insidious, which may therefore lead to sudden and severe anemia, thus causing massive and sometimes fatal hemorrhaging.

Animals↗

Further observation of content uniformity of d-alpha-tocopheryl acetate as an oily drug in granules obtained by wet granulation with a high-shear mixer.

Using d-alpha-tocopheryl acetate (VE) as a model drug, we investigated the effects of the amount of binder solution on content uniformity of oily drugs in granules obtained by, wet granulation with a high-shear mixer. When the amount of binder solution was below the water volume for the plastic limit, the content of VE was less than 50% in the fractionated fine granules, but was more than 200% in the fractionated large granules. Large variations were seen in the contents of VE even if the granulation time was extended up to 30 min. This large variation was not decreased by the milling process. On the other hand, when the amount of binder solution was at or above the water volume for the plastic limit, less variation was observed in the content of VE throughout the granules, and the content of VE was fairly uniform. Nuclei rich in VE were formed when VE was adsorbed with the powder before granulation. When the amount of binder solution was below the water volume for the plastic limit, the shearing force of mixer blades to the granules was low, so that the nuclei rich in VE were not fragmented. This led to the nonuniformity of VE content throughout the granules. On the other hand, when amount of binder solution was at or above the water volume for the plastic limit, the shearing force of mixer blades against the granules increased and became sufficient to fragment the nuclei. This led to the uniformity of VE content throughout the granules. This study showed that content uniformity of VE in the granules can be achieved by controlling the physical shearing force of mixer blades by regulating the amount of binder solution.

Antioxidants↗

Differentiation stages of eosinophils characterized by hyaluronic acid binding via CD44 and responsiveness to stimuli.

To characterize interleukin (IL)-5-induced eosinophils, we examined the expression of CD44, very late antigen (VLA)-4, and the IL-5 receptor alpha chain, as well as the levels of eosinophil peroxidase and the generation of superoxide. Eosinophils were prepared from IL-5-transgenic mice, then characterized using electron microscopy to determine their responses to stimuli. Whereas CD44 densities remained almost constant, the level of VLA-4 increased in parallel with eosinophil maturation. Although a subset of IL-5-induced eosinophils with high side scatter recovered from bone marrow and rare ones found in blood recognized hyaluronic acid (HA), most did not have this property. Bone marrow eosinophils with high side scatter and lower density contained eosinophil peroxidase, not only in granules, but also in membranous structures for 30% of this population. This population developed HA-binding ability in response to IL-3, IL-4, IL-5, granulocyte-macrophage colony-stimulating factor, macrophage inflammatory protein (MIP)-2, monocyte chemotactic protein (MCP)-1, eotaxin, nerve growth factor (NGF), and opsonized zymosan (OZ). Peripheral blood eosinophils acquired HA-binding ability in response to the same stimuli, but their responses were less than those of bone marrow eosinophils with high levels of side scatter. However, splenic eosinophils did not respond to these stimuli. Although peripheral blood eosinophils did not proliferate when stimulated by IL-5, these were the only cells that released eosinophil peroxidase in response to IL-4, MIP-2, MCP-1, eotaxin, NGF, and OZ. With the exception of a subset of bone marrow eosinophils, the ability to acquire HA binding, but not the ability to generate superoxide, correlated with eosinophil peroxidase activity and major basic protein accumulation in the granules of maturing cells.

Animals↗

Measles epidemiology and outbreak investigation using IgM test in Laos.

Following the Pan American Health Organization (PAHO) recommendation on measles elimination, the Western Pacific Region of WHO (WPR) is emphasizing accelerated measles control programme especially since the achievement of polio eradication in WPR in 2000. This includes upgraded surveillance and mass measles vaccination campaign for children aged 9 months to 4 years. However, there are limited scientific evidences supporting the feasibility of this programme in Laos. To examine measles elimination feasibility in the country, we conducted measles outbreak investigation using immunoglobulin M (IgM). From March 1999 to March 2000, we conducted 7 outbreak investigations. At the outbreak sites, we examined clinical manifestations of cases and collected individual data. About five blood samples were drawn from each outbreak, and IgM antibodies to measles were tested. Of 7 investigated outbreaks, 5 were confirmed as measles, one was chickenpox, and one occurred in the inaccessible area due to flooding. In a village of high land Lao, blood drawn was refused. Of 185 cases, 64 (34.6%) cases were immunized, and 110 (59.5%) were unimunized. The estimated vaccine efficacy is 67.9%. The number of measles cases among school-aged children was 74 (40.0%), which represented 2.5% of the total population in investigated villages. Our findings showed various difficulties of the surveillance and the limited outcomes of mass measles vaccination campaign under the accelerated measles control programme by WPR. Efforts to improve cold chain as well as increasing routine immunization coverage must be the priority of measles control.

Antibodies, Viral↗

A comparison of an open and laparoscopic appendectomy for patients with liver cirrhosis.

Liver cirrhosis is a critical factor contributing to morbidity and mortality in abdominal surgery, because patients with cirrhosis have a particularly high risk of developing bleeding, infection, and ascites. Laparoscopic appendectomy (LA) recently has gained a lot of attention around the world; however, comparisons between the benefits of LA and those of conventional open appendectomy (OA) for patients with liver cirrhosis have yet to be sufficiently compiled. In the present retrospective study, 40 patients with liver cirrhosis who were diagnosed with acute appendicitis before surgery underwent an appendectomy (OA in 25 patients and LA in 15 patients). This study focused on the operative time, amount of postoperative pain, use of analgesics, the restart of a normal diet, number of complications, length of hospital stay, and cost-effectiveness of the procedure in such patients. The amount of postoperative pain and the length of hospital stay were significantly smaller in the LA group. The mean values of the serum C-reactive protein on postoperative days 1, 3, and 7 were significantly less in the LA group. The number of wound infections and wound bleeding was also less in the LA group. The difference in the total cost of hospitalization was not significant. The cost of the operation was greater in the LA group than in the OA group, whereas the hospitalization cost in the LA group was less than that in the OA group. The results of this study suggest that LA may be superior to OA for the treatment of postoperative pain and postoperative complications for patients with liver cirrhosis. Long-term follow-up studies are still necessary, however, to determine any possible decrease in the number of late complications.

Aged↗

[Current status and future of surgical robotic systems].

In this review, we are commenting the current status and the future of surgical robotic systems. AESOP is a voice-controlled laparoscope manipulator that enables the "Solo-surgery". ZEUS is a master-slave manipulator that is characterized by its simplicity and lightness. da Vinci is another master-slave manipulator that has more range of freedom, therefore a surgeon can perform the operation with fewer difficulties. The technological development of high-quality and real-time 3D simulation, minimization of scopes and power saving techniques made these surgical robots realized. Although many pending matters such as lack of safety guideline or lack of accuracy of sensor/monitor have been raised in current surgical robotics, the development of the technologies may promise to resolve such matters in the future.

Forecasting↗

[A survey on attitudes and practice concerning International Health].

OBJECTIVE: A survey was conducted to help understanding of the attitudes and practice of Japanese medical students concerning "International Health". MATERIALS AND METHODS: One thousand seven hundred and ninety six students from eleven medical schools responded in the questionnaire study. One thousand and ninety seven were males and 699 were females with average ages of 22 and 21 years, respectively. RESULTS: 32.3% of the students answered that they have/had an interest in "International Health". About half of the students answered that they wanted to have a lecture on "International Health" and they also had a willingness to engage in activities for "International Health" someday. Further, 4% of the students had experience of participation in activities related to "International Health". Female students showed that they have a stronger willingness to take part in the "International Health activities" than males. CONCLUSION: Human resources that can work in the field of international cooperation are required because ODA from Japan has ranked first in the world for nine years in succession. However, the willingness to participate in "International Health activities" among students decreased conversely with their years of learning in medical school. This result might be a basic material when we look at the education toward "International Health" in the medical school.

Adult↗

Risk of poliomyelitis importation and re-emergence in Laos.

The declaration of poliomyelitis eradication in the western pacific region is scheduled for Oct 29, 2000, in Kyoto, Japan. Our survey in the border areas of the southeast Asia region, however, revealed that there remains a risk of re-emergence and importation of poliomyelitis into Laos. We report the evidence based on our border area investigations during the past 4 years under the bilateral supervision of the governments of Laos and Japan.

Child, Preschool↗

Serum testosterone:estradiol ratio and the development of hepatocellular carcinoma among male cirrhotic patients.

The reason for the large male predominance in the occurrence of hepatocellular carcinoma (HCC) remains unknown, and sex hormones may contribute to this phenomenon. We examined possible associations of serum levels of testosterone, free testosterone, estradiol, sex hormone binding globulin, and testosterone:estradiol ratio (T:E2 ratio) with HCC development in a follow-up study of 46 Japanese male patients with liver cirrhosis predominantly of hepatitis C virus origin (76%). Serum samples were collected between December 1985 and December 1987, and the patients were completely followed until the end of 1995 for an average of 5.1 years. During the follow-up period, 20 patients (43%) developed HCC. Univariate analysis demonstrated that serum T:E2 ratio and testosterone were significant predictors of HCC; the hazard ratios (and 95% confidence intervals) in the middle and upper tertiles relative to the lower tertile were 2.0 (0.5-7.6) and 4.0 (1.1-14.6; P trend = 0.03) for T:E2 ratio and 0.8 (0.2-3.1) and 2.9 (1.0-8.5; P trend = 0.05) for testosterone. Adjustment for age, serum albumin, hepatitis virus markers, and other clinicobiological variables substantially increased the corresponding hazard ratios. In multivariate analysis, serum free testosterone appeared to be associated with increased risk, yet independent associations with estradiol and sex hormone binding globulin were not evident. These results indicate that elevated serum testosterone, together with decreased serum estrogens, may promote the development of HCC in cirrhosis.

Adult↗

A new surgical strategy for cirrhotic patients with hepatocellular carcinoma and hypersplenism. Performing a hepatectomy after a laparoscopic splenectomy.

BACKGROUND: Hepatectomy for cirrhotic patients with hypersplenism is a high-risk operative procedure. We report herein a new strategy for high-risk patients with hepatocellular carcinoma (HCC). METHODS: Six cirrhotic patients with HCC and hypersplenism received a partial hepatectomy after first undergoing a laparoscopic splenectomy. We then compared the variables for these patients before splenectomy and before hepatectomy. RESULTS: The platelet count and the white blood cell count were found to be significantly elevated before hepatectomy. The ammonia value decreased significantly before hepatectomy. The albumin value tended to be elevated before hepatectomy. Furthermore, the Child's classification of all patients improved significantly before hepatectomy. However, other variables-such as the indocyanine green dye excretion test at 15 min and the bilirubin value-did not change after splenectomy. For hepatectomy patients who first underwent a laparoscopic splenectomy, operation time ranged from 265 to 440 min (average time, 361 min), and blood loss ranged from 500 to 2,200 ml (median volume, 1,300 ml). Four of six patients did not require any blood transfusion; furthermore, no patient needed a platelet-rich plasma transfusion. All but one patient, who suffered postoperatively from an intractable duodenal ulcer, had an uneventful postoperative course. CONCLUSION: Partial hepatectomy after an initial laparoscopic splenectomy is a new and effective choice of treatment for cirrhotic patients with HCC and hypersplenism.

Aged↗