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Biomedical subjects

S Kondo

Publications and source records attributed to S Kondo.

At least 325 records · Page 18Linked to original sources
PubMed1998

Ischemic stricture of the small intestine associated with acute pancreatitis.

A 37-yr-old man underwent an open drainage operation for severe acute pancreatitis and received respiratory ventilation support for 4 mo because of respiratory failure based on disseminated intravascular coagulation (DIC) and septic shock. Under intensive care, he sometimes had bloody diarrhea for about 6 wk. Colonoscopic findings suggested that the bleeding had derived from the small intestine. The patient then gradually recovered from acute pancreatitis and was discharged from the hospital. Thereafter, he suffered relapses of ileus and his symptoms progressively worsened. The patient underwent a second operation about 2 yr after the onset of acute pancreatitis. At celiotomy, multiple stenoses of the distal ileum measuring about 60 cm in length were found and the segment was resected. The resected specimen demonstrated six separate circumferential strictures and shallow ulcerations. Histologically, multiple ulcerations were restricted to the mucosa and were accompanied by marked submucosal edema and fibrosis. The mucosa between the ulcers revealed chronic regenerative changes: intimal thickening of small mesenteric arteries causing luminal narrowing and organized thrombosis in small mesenteric veins. Therefore, these were considered to be a series of segmental ischemic lesions. Note that delayed ischemic stricture of the small intestine may occur as a chronic complication of acute pancreatitis.

Acute Disease↗
PubMed1998

Clinical significance of reduced cerebral metabolism in multiple sclerosis: a combined PET and MRI study.

Magnetic resonance imaging (MRI) in patients with multiple sclerosis (MS) has provided major insights into the disease's natural history, and many studies have focussed on possible correlations between MRI findings and the clinical manifestations of MS. In contrast, there are few reports on possible relationships between functional imaging data and cognitive function. The present study assessed the relationship between clinical presentation and combined anatomical and functional imaging data in MS. Twenty patients with definite MS underwent MRI and positron emission tomography (PET) to evaluate cerebral blood flow (rCBF) and oxygen metabolism (rCMRO2). The relationships between these neuroimaging findings and clinical data, including the Expanded Disability Status Scale (EDSS), Mini-mental status scale, Hasegawa Dementia Scale and relapse time, were evaluated with Spearman's rank correlation coefficients. A general reduction in rCBF and rCMRO2 in the gray and white matter were found in the MS patients. EDSS was correlated with the number and size of the lesions on MRI and was negatively correlated with rCMRO2. A correlation between the decrease in rCMRO2 and the level of cognitive impairment was also found. The severity of cerebral hypometabolism was also related to the number of relapses. Morphological and functional findings obtained by MRI and PET are closely related to the clinical status in MS. Our results suggest that measurement of cerebral metabolism in MS has the potential to be an objective marker for monitoring disease activity and to provide prognostic information.

Adult↗
PubMed1998

Aneurysmal rupture of the pancreaticoduodenal artery successfully treated by transcatheter arterial embolization.

We report a case of aneurysmal rupture of the pancreaticoduodenal artery successfully treated by transcatheter arterial embolization. A 61-year-old man with a history of hypertension underwent surgery at our hospital in November 1995 for local peritonitis caused by perforation of the sigmoid colon secondary to cancer. On the 9th postoperative day, he developed shock, with complaints of epigastric and back pain. Abdominal computed tomography showed an enhanced mass, thought to be a peripancreatic aneurysm. Emergency angiography demonstrated an aneurysm arising from the arcade of the anterior pancreaticoduodenal artery. After diagnostic angiography, transcatheter arterial embolization was performed. With steel coils, the anterior superior pancreaticoduodenal artery and anterior inferior pancreaticoduodenal artery were embolized near the origin of the aneurysm. Angiography 7 weeks later revealed no recanalization of the aneurysm and the absence of anomalous collateral vessels. The patient has been well for 19 months without re-bleeding or recurrence of sigmoid colon cancer. Transcatheter arterial embolization is an effective therapeutic approach for aneurysm of the pancreaticoduodenal artery and is the preferred initial treatment.

Aneurysm, Ruptured↗
PubMed1998

Aggressive surgical treatment of hilar cholangiocarcinoma.

Recent progress in surgical techniques for and the perioperative management of hilar cholangiocarcinoma has led to improved outcomes for aggressive liver and bile duct resections, which, however, still show considerable morbidity and mortality. In this article, the results of pioneers' attempts in hepatobiliary surgery for difficult hilar cholangiocarcinomas are reviewed. It is recommended that curative hepatobiliary resection should be performed for hilar cholangiocarcinoma, with careful preoperative management of patients complicated with several difficult conditions.

Bile Duct Neoplasms↗
PubMed1998

A dynamic neural network with temporal coding and functional connectivity.

A neural network model capable of altering its pattern classifying properties by program input is proposed. Here the "program input" is another source of input besides the pattern input. Unlike most neural network models, this model runs as a deterministic point process of spikes in continuous time; connections among neurons have finite delays, which are set randomly according to a normal distribution. Furthermore, this model utilizes functional connectivity which is dynamic connectivity among neurons peculiar to temporal-coding neural networks with short neuronal decay time constants. Computer simulation of the proposed network has been performed, and the results are considered in light of experimental results shown recently for correlated firings of neurons.

Computer Simulation↗
PubMed1998

A new method to prevent wound infection: a controlled clinical trial in patients with combined liver and bile duct resection.

INTRODUCTION: Despite advances in antibiotic prophylaxis, postoperative wound infection remains a major source of morbidity after digestive surgery. Its prevention is a challenging problem, especially in high-risk patients. The authors introduced a new method to prevent surgical wound infections and evaluated its efficacy in a prospective, randomized trial in markedly high-risk patients. METHODS: Patients with biliary tract carcinoma who were scheduled to undergo combined liver and extrahepatic bile duct resection with biliary reconstruction were randomly assigned to one of two groups, well matched in terms of clinical characteristics at baseline. In one group the new treatment was employed (sealed group, n=31), and in the other the wound was treated in the usual fashion (open group, n=28). In the sealed group, povidone-iodine gel was administered to the subcutaneous tissue, and the skin and peritoneum were approximated with a continuous suture. Wound infection was registered up to 30 days after surgery. RESULTS: Wound infection occurred in 18 patients: 5 (16%) patients in the sealed group and 13 (46%) in the open group (P<0.05). All 18 underwent preoperative percutaneous transhepatic biliary drainage and had positive bile culture findings. In 13 of these 18 patients (72%) the microorganisms isolated from the infected wound were identical to those in the bile. CONCLUSIONS: Our results confirm the close association between infected bile and wound infection in hepatobiliary surgery. Our new method, "direct wound sealing," is simple, easy to perform, virtually cost-free, and has the potential to prevent wound infections even in markedly high-risk patients.

Anti-Infective Agents, Local↗
PubMed1998

The gene for mesomelic dysplasia Kantaputra type is mapped to chromosome 2q24-q32.

Mesomelic dysplasia Kantaputra type (MDK) (MIM *156232) is a new autosomal dominant skeletal dysplasia characterized by dwarfism, shortening of the forearms/lower-legs, carpal/tarsal synostosis, and dorsolateral foot deviation. We studied a Thai family in which 15 members in 3 generations were affected with MDK. With reference to the breakpoints of a balanced translocation [t(2;8)(q31;p21)] in patients from a previously reported Italian family with a skeletal dysplasia that appears similar to MDK, a linkage analysis was performed in the Thai family using 50 CA-repeat markers mapped to nearby regions (2q22-q34 and 8p24-p21) of the translocation breakpoints. The results clearly ruled out a linkage of MDK to marker loci at the 8p24-p21 region, whereas all nine affected members available for the study shared a haplotype at four loci (D2S2284, D2S326, D2S2188, and D2S2314) spanning about 22.7 cM in the 2q24-q32 region. The computer-assisted two-point linkage analysis revealed maximum logarithm of odds (lod) scores of 4.82, 4.21, 4.82, and 4.21 (theta = 0) at these loci, respectively. These data indicated that the MDK locus is in the vicinity of D2S2284 and D2S2188 loci that are most likely mapped to 2q24-q32.

Chromosome Mapping↗
PubMed1998

Sex differences in function and distribution of beta-adrenoceptors in rabbit urinary bladder.

PURPOSE: To examine whether there are sex-related differences in urinary bladder function, we evaluated the function and distribution of beta-adrenoceptor in the male and female rabbit urinary bladder. MATERIALS AND METHODS: Ten male and ten female rabbits were studied. The function and distribution of beta-adrenoceptors were studied by measuring changes in contractile forces from isoproterenol, a beta-adrenoceptor agonist, and forskolin, an adenylate cyclase activator, and by measuring beta-adrenoceptor densities using radioligand receptor binding techniques. RESULTS: Isoproterenol caused significantly greater relaxation in female trigonal muscles than in male trigonal muscles. It caused similar relaxation responses in the male and female detrusors. The Bmax values for [3H]dihydroalprenolol (DHA) binding in trigonal muscles were significantly higher in the female than in the male, whereas Bmax values for [3H]DHA binding in the male and the female detrusor were similar. In contrast, forskolin caused similarly marked relaxations in the male and the female detrusor and trigonal muscles. CONCLUSION: These findings demonstrate that there are sex-related differences in the function and the distribution of beta-adrenoceptors in rabbit trigonal smooth muscles.

Adrenergic beta-Agonists↗
PubMed1998

A paired wedge filter system for compensation in dose differences.

OBJECTIVE: In radiotherapy, it is important to conform the high dose volume to the planned target volume. A variable thickness paired wedge filter system was developed to compensate for dose inhomogeneity arising from field width segment variation in conformal irradiation. MATERIALS AND METHODS: The present study used a 6 MV linear accelerator equipped with multileaf collimator leaves and a paired wedge compensating filter system. The dose variation due to field width was measured in each field segment width. The variation in attenuation of the compensators was measured as a function of filter position. As the field width increases, the relative absorbed dose also increases; this is the point of requiring compensation, so it can be in reverse proportion. RESULTS: As the field width increases, the relative absorbed dose also increases; this is why compensation is required and thus it must be in reverse proportion. Attenuation of the absorbed dose by the paired filters was in proportion to the filter position. The filter position to compensate for the difference of absorbed doses was defined by the square root of the field width. For a field varying in width from 4 to 16 cm, the variation in the absorbed dose across the field was reduced from 12% to 2.7%. CONCLUSION: This paired wedge filter system reduced absorbed dose variations across multileaf collimator shaped fields and can facilitate treatment planning in conformal therapy.

Humans↗
PubMed1998

Primary lymphoma of the liver with bile duct invasion and tumoral occlusion of the portal vein: report of a case.

A 55-year-old woman presented to hospital with epigastric pain and jaundice. Diagnostic imaging studies revealed a biliary stricture of the hepatic confluence and a hepatic tumour of the left and caudate lobes with a portal tumour thrombus, which occupied the main portal trunk, the umbilical portion of the left portal vein, and the right anterior and posterior portal branches. Left hepatic trisegmentectomy, caudate lobectomy, portal tumour thrombectomy, bile duct resection and bilioenteric anastomosis were performed. There were no other lesions, and so it was diagnosed as a primary lymphoma of the liver (B-cell, diffuse, large cell type). The patient underwent postoperative chemotherapy and has remained well for 4.5 years after surgery. Primary lymphoma of the liver is very rare, and this is the first case report with bile duct invasion and tumoral occlusion of the portal vein.

Bile Duct Neoplasms↗
PubMed1998

Biochemical and immunohistochemical analyses of keratin expression in basal cell carcinoma.

Recently we demonstrated that the keratin 17 (K17) content exceeded the K16 content in most follicular tumors, in comparison with non-follicular epithelial skin tumours by two-dimensional gel electrophoresis (2-DE), densitometry and immunohistochemistry. At present the origin of basal cell carcinoma (BCC) is unknown. So, based on the above results, we studied keratin expression in eight cases of BCC, in order to analyze tumor differentiation by both biochemical and immunohistochemical methods. Biochemically, using 2-DE and immunoblotting, stratified epithelial keratins K5/K14 and large amounts of K17 were present in all cases. Simple epithelial keratins K8 and K19 were expressed in all and half of the cases, respectively. However, hyperproliferative associated keratins (K6/K16) and keratinized keratins (K1/K10) were detected in only a few cases. Immunohistochemical studies using frozen sections with chain-specific antikeratin monoclonal antibodies against K1, K7, K8, K10, K14, K16, K17, K18 and K19 showed that BCC tumor cells reacted positively with antibodies against K8, K14, K17 and K19, but did not react, or were rarely positive with K1, K7, K10, K16 and K18 antibodies. Predominant expression of K17 and the frequent expression of K8 and K19, with little K6/K16 and K1/K10 expression are the characteristic features of BCC, suggesting that BCC is differentiated towards undifferentiated follicular epithelia, most probably hair bulge cells.

Aged↗
PubMed1998

1alpha,24-dihydroxyvitamin D3 (tacalcitol) is effective against Hailey-Hailey disease both in vivo and in vitro.

We report a case of Hailey-Hailey disease (HHD) in which 1alpha, 24-dihydroxyvitamin D3 (tacalcitol) was effective both clinically (in vivo) and in explant cultures (in vitro) of a skin lesion. The patient was a 65-year-old man with HHD lesions in the axillary and inguinal areas bilaterally. We applied ointment containing 1alpha, 24-dihydroxyvitamin D3 (tacalcitol), an analogue of active vitamin D3, to the lesions and assessed its clinical effectiveness. The HHD lesions in both groins disappeared after treatment with the 1alpha, 24-dihydroxyvitamin D3 ointment, and the remission has continued to the present. A punch biopsy specimen of the lesion that had remitted showed no acantholysis. In addition, dissociation of migrating keratinocytes was observed when biopsy specimens of the HHD skin lesion were cultured in medium without 1alpha,24-dihydroxyvitamin D3, but inhibition of keratinocyte dissociation was observed in medium containing it. These results suggest the effectiveness of 1alpha, 24-dihydroxyvitamin D3 against HHD both in vivo and in vitro.

Aged↗
PubMed1998

Different gastric emptying of solid and liquid meals after pylorus-preserving pancreatoduodenectomy.

BACKGROUND: Transient gastric stasis immediately after pylorus-preserving pancreatoduodenectomy (PPPD) is a common complication, but the cause remains unknown. Changes in gastric emptying were investigated in patients undergoing PPPD for periampullary malignancy. METHODS: In 14 patients undergoing PPPD, liquid- and solid-phase gastric emptying were evaluated before and after operation (mean 38 (range 27-53) days after operation). Two pharmacological gastric-emptying tests were used: the acetaminophen test for liquid-phase emptying and the sulphamethizole capsule food test for solid-phase gastric emptying. RESULTS: All patients exhibited delayed solid emptying but fairly good liquid emptying. CONCLUSION: Gastric function in the early postoperative period after PPPD is characterized by delayed solid-phase but good liquid-phase emptying.

Acetaminophen↗
PubMed1998

Selective neutrophil depletion with monoclonal antibodies attenuates ischemia/reperfusion injury in skeletal muscle.

The purpose of this study was to determine whether depletion of circulating neutrophils, using an antineutrophil monoclonal antibody (RP3), would attenuate ischemia/reperfusion injury in rat skeletal muscle. A 3- and 5-hr period of ischemia was induced unilaterally into the hindlimbs of rats; the isolated limbs were then reperfused for 24 hr after ischemia. The gastrocnemius muscle was then removed, and blood was taken simultaneously. The hematologic parameters were measured, muscle neutrophil sequestration was assessed by myeloperoxidase (MPO) activity, free radical production was evaluated by the tissue lipid peroxides (LPO) levels, muscle viability was assessed by tissue levels of adenosine triphosphate (ATP) and creatine phosphate (PCr) levels, and muscle wet/dry weights were determined. Treatment with RP3 selectively and sufficiently depleted the circulating neutrophil population, markedly reduced MPO, and significantly attenuated LPO and the tissue water content after both 3- and 5-hr of ischemia. After 3 hr of ischemia, ATP and PCr levels were significantly increased by neutrophil depletion; however, after 5 hr of ischemia, the same effect was not demonstrated. These results suggest that neutrophil depletion after 3 hr of ischemia restrains free radical production and edema formation, and also attenuates skeletal muscle ischemia reperfusion injury; however, after 5 hr of ischemia, ischemic damage was so severe, that neutrophil depletion did not reduce ischemia reperfusion injury.

Adenine Nucleotides↗
PubMed1998

The high susceptibility of heterozygous p53(+/-) mice to malformation after foetal irradiation is related to sub-competent apoptosis.

PURPOSE: To investigate the relationship between the incidence of radiation-induced malformations and the extent of p53-dependent apoptosis. MATERIALS AND METHODS: Wild-type p53(+ / +) and heterozygous p53(+ / -) mice were exposed to X-rays at the mid-gestational period. The incidence of anomalies and prenatal deaths, the extent of apoptosis, and the levels of p53 protein were assessed. RESULTS: After X-irradiation with 2 Gy, the incidence of malformation (corrected for control levels) was 0 and 30%, respectively, for p53(+ / +) and p53(+ / -). After irradiation of p53(+ / +) foetuses with 3 Gy, the frequency (F) of apoptotic cells rapidly peaked at 80% at 4 h and fell close to the control level at 48 h. The relationship between F 4h after irradiation and dose (D) (1-3Gy) is accurately expressed by a single-hit equation, F= 1 -exp ( -(a + bD)¿, where the radiation-induced apoptosis rate, b, is 0.47 for the wild type and 0.22 for the heterozygous mice. The X-irradiated foetuses showed no increase in the levels of p53 protein. CONCLUSION: The higher susceptibility of irradiated p53(+ / -) foetuses to malformation is related to a twofold lower rate of apoptosis; competent removal by apoptosis of damaged cells from irradiated tissues is impaired dramatically if one of two wild-type p53 alleles is lost. The frequency of apoptotic cells in the wild type reached a maximum 4h after foetal irradiation with no measurable increase in the level of p53 protein, indicating that radiation-induced p53-mediated foetal apoptosis depends on non-transcriptional events.

Alleles↗
PubMed1998

Microinjection methods for visualization of the vascular architecture of the mouse embryo for light and scanning electron microscopy.

Injection of certain materials into blood vessels enables three dimensional visualization of vascular architecture and has provided abundant information which is not available by reconstruction of serial sections. By injection methods, the vascular architecture can be visualized either with scanning electron microscopy (SEM) after injection of resin and tissue digestion or with light microscopy (LM) after injection of barium sulfate and tissue clearing. The author has successfully observed whole blood vessels of 13.5-18.5 day mouse embryos using the collodion cast method in SEM. In mouse embryos younger than 12.5 embryonic days, a part, not whole, of blood vessels was obtained using cast colloiding. When the X-ray contrast medium was injected, the whole vasculature of the 9.5 day embryo was elucidated with LM, and the backscattered electron image and the secondary electron image of the identical area in the lung alveolar capillaries of the 17.5 day embryo were obtained with SEM, which showed the spatial relationship between the capillaries and their circumferential cells three dimensionally. Cast and injection methods are reviewed with respect to their application for investigating the development of mouse embryo.

Animals↗
PubMed1998

Antisense telomerase treatment: induction of two distinct pathways, apoptosis and differentiation.

Telomerase, the enzyme that elongates telomeric DNA (TTAGGG)n, may be involved in cellular immortality and oncogenesis. To investigate the effect of inhibition of telomerase on tumor cells, we transfected the antisense vector against the human telomerase RNA into human malignant glioma cells exhibiting telomerase activity. After 30 doublings, some subpopulations of transfectants expressed a high level of interleukin-1beta-converting enzyme (ICE) protein and underwent apoptosis. In contrast, other subpopulations also showed enhanced ICE protein but escaped from apoptotic crisis and continued to grow, although their DNA synthesis, invasive ability, and tumorigenicity in nude mice were significantly reduced. Surviving cells demonstrated increased expression of glial fibrillary acidic protein and decreased motility, consistent with a more differentiated state. These cells also contained enhanced expression of the cyclin-dependent kinase inhibitors (CDKIs) p21 and p27. Treatment of surviving nonapoptotic cells with antisense oligonucleotides against p27, but not p21, induced apoptotic cell death, suggesting that p27 may have protected differentiating glioma cells from apoptosis. These data show that treatment with antisense telomerase inhibits telomerase activity and subsequently induces either apoptosis or differentiation. Regulation of these two distinct pathways may be dependent on the expression of ICE or CDKIs.

Animals↗