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Biomedical subjects

K Yamaguchi

Publications and source records attributed to K Yamaguchi.

At least 541 records · Page 30Linked to original sources
PubMed1998

A large inflammatory polyp of the gallbladder masquerading as gallbladder carcinoma.

An inflammatory polyp of the gallbladder is a rare variant of benign gallbladder polyp. Differentiation between an inflammatory polyp and polypoid gallbladder carcinoma is difficult when the polyp is more than 1 cm in diameter. We report a rare case of a large inflammatory polyp of the gallbladder masquerading as gallbladder carcinoma in a 37-year-old Japanese woman who was incidentally diagnosed with a large gallbladder polyp, measuring 1 cm in diameter, by ultrasonography. She was asymptomatic and physical examination was unremarkable. Abdominal ultrasonography and endoscopic ultrasonography revealed three polypoid lesions in the gallbladder. One lesion was an isoechoic polyp, measuring 15 x 8 mm, showing a nodular surface and located in the fundus of the gallbladder. The other two lesions were hyperechoic polyps, measuring 5 x 5 mm, in the body of the gallbladder. Computed tomography and magnetic resonance imaging revealed marked enhancement of the largest polypoid lesion by dynamic study, and no lymph node enlargement was noted. Endoscopic retrograde cholangiography revealed a 12 x 8 mm polyp with an irregular surface in the fundus of the gallbladder. Superselective angiography of the cystic artery revealed neovascularity and a tumor stain in the fundus of the gallbladder. Cholecystectomy with lymph node dissection was performed. Intraoperative frozen section diagnosis of the largest polyp was an inflammatory polyp of the gallbladder. The other two polyps were cholesterol polyps. Inflammatory polyp should be considered as a differential diagnosis of hypervascular gallbladder polyps that measure more than 1 cm in diameter.

Adult↗
PubMed1998

Complications and management of microwave coagulation therapy for primary and metastatic liver tumors.

Microwave coagulation therapy (MCT) has been widely used, both percutaneously and directly, as effective minimal invasive therapy for liver tumors. To facilitate the use of MCT, we describe the complications we have encountered, and their possible management and prophylaxis. MCT was performed for 42 patients with hepatocellular carcinoma (HCC) and for 29 with metastatic liver tumors, following which complications developed in 14.2% and 20.6% of the HCC and metastatic groups, respectively. The complications included abscess, biloma, bleeding, hepatic failure, and dissemination of cancer cells. In the HCC group, the mean value of tumor size and the clinical stage of patients with complications were significantly larger (P = 0.006) and higher (P = 0.032), respectively, than those of patients without complications. The incidence of complications increased significantly when the tumor size was more than 4cm (P = 0.008). Abscesses and bleeding were successfully treated using percutaneous drainage and interventional angiography, respectively, but as the other serious complications were not able to be treated effectively once induced, prophylaxis is important to facilitate MCT. Transcatheter cooling of the intrahepatic bile duct during MCT and the administration of an anticancer agent into the abdominal cavity are recommended to prevent biloma and dissemination, respectively. MCT is indicated for tumors less than 4 cm in diameter to reduce the risk of complications. The prophylaxis and treatment of these complications enhance the safety of MCT.

Aged↗
PubMed1998

Comparison of endoscopic retrograde and magnetic resonance cholangiopancreatography in the surgical diagnosis of pancreatic diseases.

BACKGROUND: Magnetic resonance cholangiopancreatography (MRCP) is a newly developing noninvasive examination of the biliopancreatic trees. Roles of MRCP in the diagnosis of pancreatic diseases have not been scrutinized. METHODS: Endoscopic retrograde cholangiopancreatography (ERCP) and MRCP were reviewed in 52 Japanese patients with various pancreatic diseases and 6 patients with normal pancreas to compare their diagnostic usefulness and limitation. RESULTS: In those with normal pancreas, only the main pancreatic duct was visualized by MRCP, while both the main pancreatic and branch ducts were clearly delineated by ERCP. In 3 patients with serous cystadenoma, the tumor was not visualized by ERCP, whereas it was visible as a high-intensity mass on MRCP. Of 18 patients with a "mucin hypersecreting" tumor of the branch type, MRCP demonstrated cystically dilated branch ducts in all, while ERCP failed to visualize the dilated ducts in 6 patients. However, the details of the cystic lesions (mural nodule, communication with the main pancreatic duct) were more exactly demonstrated by ERCP than MRCP. In 5 patients with a mucin hypersecreting tumor of the main pancreatic duct type, the dilated main pancreatic duct and the presence of mural nodules were similarly demonstrated both by ERCP and MRCP. In 12 patients with pancreatic adenocarcinoma, indirect findings were similarly demonstrated both by ERCP and MRCP, ie, stenosis (4 patients) and obstruction (8) together with dilation of the main pancreatic duct (9). In 3 patients, the center of the mass showed high intensity on MRCP, suggesting the secondary change of pancreatic carcinoma. In 8 patients with obstruction of the main pancreatic duct due to carcinoma, the distal pancreatic duct was visualized by MRCP but not by ERCP. In 9 patients who had undergone pylorus-preserving or standard pancreatoduodenectomy, follow-up MRCP was obtainable in all examined and displayed the main pancreatic duct. CONCLUSIONS: MRCP plays a complementary role in the surgical diagnosis of pancreatic disorders and is especially useful to examine the pancreatic duct after pancreatoduodenectomy.

Adenocarcinoma↗
PubMed1998

Litmus paper helps detect potential pancreatoenterostomy leakage.

BACKGROUND: Leakage of pancreatoenterostomy remains as a serious and fatal complication after pancreatectomy. Several risk factors have been reported, ie, normal pancreatic parenchyma, small pancreatic duct, a large amount of intraoperative blood loss, management of the cut surface of the pancreas, and the presence of preoperative jaundice. Transected pancreatic ductules on the cut surface of the pancreas that are not drained into the main pancreatic duct after pancreatectomy are one of the risks. The pancreatic juice is alkaline and turns red litmus to blue. METHODS: In order to detect the transected pancreatic ductules on the cut surface of the pancreas, red litmus paper is applied to the cutting surface of the pancreas after stimulation of secretin. RESULTS: Nondrained, transected pancreatic ductules on the cut surface of the pancreas can be detected as blue spots on the red litmus paper. The corresponding areas to the blue spots can be transfixed with sutures to close the nondrained and transected pancreatic ductules. CONCLUSION: Litmus paper can be expected to detect pancreatoenterostomy leakage after pancreatectomy.

Humans↗
PubMed1998

Changes in pancreatic function after pancreatoduodenectomy.

BACKGROUND: The objective of this study was to compare the alterations in pancreatic function after pancreatoduodenectomy between malignant and benign diseases. METHODS: In 34 patients who underwent pancreatoduodenectomy for pariampullary cancer (malignant group; n = 18) and benign pancreatic disorders (benign group; n = 16), exocrine and endocrine functions were analyzed before surgery, at a short-term period (< or = 2 months), and at a long-term period (>12 months) after surgery. Assessment was based on the BT-PABA excretion test, fasting blood sugar level, and oral glucose tolerance test. RESULTS: Compared with the preoperative level, urinary PABA excretion rate in the malignant group significantly decreased on short-term follow-up but recovered on long-term follow-up. However, that in the benign group increased on long-term follow-up without showing a short-term decline. Diabetes mellitus was present in 11 (61%) of the 18 patients in the malignant group and 6 (38%) of the 16 in the benign group before surgery. Glucose tolerance improved in 6 (55%) of the 11 patients in the malignant group but in only 1 (17%) of the 6 in the benign group shortly after surgery. In the benign group, 3 (30%) of 10 patients with normal preoperative glucose tolerance became diabetic after surgery, while no patient in the malignant group developed diabetes on short-term follow-up. CONCLUSIONS: Surgeons should pay attention to exocrine pancreatic function in patients with a periampullary cancer and to glucose metabolism in patients with benign disease over the short-term period after pancreatoduodenectomy.

4-Aminobenzoic Acid↗
PubMed1998

Duct-parenchymal ratio predicts exocrine pancreatic function after pancreatoduodenectomy and distal pancreatectomy.

BACKGROUND: The postoperative exocrine pancreatic function was compared between pancreatoduodenectomy and distal pancreatectomy, and we studied the relationship between the preoperative morphology of the pancreas expected to remain and pancreatic function after surgery. PATIENTS AND METHODS: In 27 patients who underwent pylorus-preserving pancreatoduodenectomy (PPPD group) and 12 who underwent distal pancreatectomy (DP group), the exocrine pancreatic function was assessed using the BT-PABA excretion test before surgery and short term after surgery (< or =2 months). Preoperative morphology of the pancreas at a presumed line of transection was also investigated on computed tomography. RESULTS: The mean urinary PABA excretion rate in the PPPD group decreased from 68.3% to 53.7% (P = 0.0029), whereas that in the DP group showed no significant change (70.7% versus 72.7%). The mean size of the main pancreatic duct at the presumed transection line in the PPPD group was significantly greater than that in the DP group (6.5 mm versus 2.6 mm, P = 0.0002). The mean parenchymal thickness of the pancreatic gland at the presumed transection line in the PPPD group was significantly smaller than that in the DP group (16.1 mm versus 18.6 mm, P = 0.04). The mean ratio of the pancreatic duct caliber to parenchymal thickness (duct-parenchymal ratio) in the PPPD group was significantly higher than that in the DP group (0.43 versus 0.14, P = 0.0004). There was a significant negative correlation between the postoperative PABA excretion rate and the duct-parenchymal ratio (P = 0.0057). CONCLUSIONS: The postoperative exocrine pancreatic function after PPPD and DP was significantly influenced by the morphology of the pancreas at the presumed transection line. It is important to evaluate the preoperative morphology of the presumably remaining pancreas, especially duct-parenchymal ratio, to predict the exocrine pancreatic function short term after pancreatectomy.

Adult↗
PubMed1998

IL-2-induced growth of CD8+ T cell prolymphocytic leukemia cells mediated by NF-kappaB induction and IL-2 receptor alpha expression.

The binding of interleukin-2 (IL-2) to its receptor on normal T cells induces nuclear expression of nuclear factor kappaB (NF-kappaB), activation of the IL-2 receptor (IL-2R) alpha chain gene, and cell proliferation. In the present study, the role of IL-2R signaling in the growth of CD8+ T cell prolymphocytic leukemia (T-PLL) cells has been investigated. Flow cytometry revealed that primary leukemia cells from a patient with CD8+ T-PLL expressed IL-2Ralpha and beta chains, and the cells showed a proliferative response and an increase in IL-2Ralpha expression on culture with exogeneous IL-2. Northern blot analysis failed to detect IL-2 mRNA, suggesting that IL-2 may act in a paracrine manner in vivo. Electrophoretic mobility-shift assays revealed that recombinant IL-2 increased NF-kappaB binding activity in nuclear extracts of the leukemia cells, and Northern blot analysis showed that IL-2 increased the abundance of mRNAs encoding the NF-kappaB components c-Rel and KBF1 in these cells. IL-2 binding analysis demonstrated that IL-2 markedly increased the number of low affinity IL-2Rs on the leukemia cells, without an effect on the number of high-affinity IL-2Rs. These results show that IL-2 is capable of inducing the nuclear expression of NF-kappaB in primary CD8+ T-PLL cells, and that this effect is mediated, at least in part, at a pretranslational level.

Blotting, Northern↗
PubMed1998

Effect of EPC-K1 on myocardial infarct size in a rat model with coronary artery occlusion and reperfusion.

1. The ability of EPC-K1 to improve myocardial infarction was evaluated in a rat model with coronary artery occlusion and reperfusion. 2. The myocardial infarct size was 30.5 +/- 1.7% by intravenous (i.v.) administration and 28.8 +/- 2.7% by intraduodenal (i.d.) administration of the saline EPC-K1 at doses between 1 and 10 mg/kg, i.v. and at doses between 50 and 200 mg/kg, i.d., reduced myocardial infarct size dose dependently. Significant reduction in myocardial infarct size was found at a dose of 10 mg/kg, i.v., and 200 mg/kg, i.d.

Animals↗
PubMed1998

Microcirculation of the distal humeral epiphyseal cartilage: implications for post-traumatic growth deformities.

The purpose of this study was to determine if there is an anatomic basis for development of the avascular necrosis infrequently seen after elbow trauma. The microcirculation to the distal humeral epiphyseal cartilage was studied in 38 elbow joints from 19 skeletally immature individuals. The findings of this study were as follows: (1) Vascularity is centripetal within the epiphyseal cartilages of the capitellum, trochlea, and medial and lateral epicondyles. Because of this vascularity pattern, it is not easy for avascular necrosis to develop after trauma within these epiphyses. (2) Vascularity is longitudinal in the epiphyseal cartilage between the capitellum and trochlea. The longitudinal vessels appear susceptible to fractures around the elbow in childhood. (3) A rich vascular network exists in the olecranon fat pad, and a vascular arch forms from the vascular network adjacent to the distal humeral epiphyseal cartilage. The vascular arch sends several large branches into the epiphyseal cartilage in a vertical fashion. Disruption of either the longitudinal intraosseous vasculature (vertical extraosseous blood supply) or the vascular arch in more than 2 places may lead to selective avascular necrosis of the epiphyseal cartilage between the capitellum and trochlea. These findings suggest vascular compromise as a possible explanation for "fish-tail" deformities seen as sequellae of different fracture patterns.

Female↗
PubMed1998

Early intervention for very-low-birth-weight infants.

To assess the efficacy of early intervention (EI) for very-low-birth-weight (VLBW) infants, we evaluated 62 2 year old children who were enrolled in an EI program and 48 control subjects aged 2 years. We determined the subjects' developmental quotients (DQ) and obtained information about the parents' evaluation of the children from a questionnaire sent to the parents. There was no significant difference in the DQ between the EI group and the control group. However, based on the responses to the questionnaire, subjects in the EI group showed slight, but statistically marginally significant, improvements in behavioral problems, especially a decrease in hyperkinesia, in adjusting to a circadian sleep cycle, and an improvement in language development, as compared with the control group (P < 0.1). Thus, EI for VLBW infants is considered useful to enhance some areas of development.

Child Behavior↗
PubMed1998

Maturational change of KCl-induced Ca2+ increase in the rat brain synaptosomes.

To investigate maturational change in the susceptibility of voltage-dependent calcium (Ca2+) channels (VDCC) in the brain to excessive depolarization, which is likely to occur during hypoxia or ischemia, we studied depolarization-induced increases in Ca2+ concentration in cortical synaptosomes ([Ca2+]i) obtained from young (8, 15, 22, 36, and 43-day-old) and adult rats using fura 2-AM as a Ca2+ indicator. The effects of Ca2+ antagonists on the increase were also studied. The maximal increase in [Ca2+]i caused by 50 mM KCl-induced depolarization was significantly lower in 8-day-old rats (73.3 nM) compared with that in adult rats (133.6 nM). On the other hand, the time necessary for [Ca2+]i to decrease to 50% of its maximal level (tau) was significantly shorter in immature rats compared with that in adult rats and was particularly short in 8- and 15-day-old rats (0.28 and 0.40 min vs. 3.85 for adult rats). The maximal increase in [Ca2+]i in 22-day-old rats and tau in adult rats were markedly reduced by verapamil, omega-agatoxin IVA, and omega-conotoxin GVIA (antagonists of L-, P-, and N-type Ca2+ channels, respectively) to similar extents, while a mixture of the three antagonists markedly decreased both maximal increase and tau in 8- and 22-day-old and adult rats. These results indicate that depolarization-induced Ca2+ influx through VDCCs in immature rat brain is less pronounced than that in adult rats, and suggest that the susceptibility of all of L-, N-, and P-type Ca2+ channels is increased during maturation in the first few weeks after birth. This lower susceptibility to depolarization might be involved in the resistance to hypoxia in immature animals.

Aging↗
PubMed1998

Sjögren-Larsson syndrome: postmortem brain abnormalities.

Brain abnormalities were described in a patient who had experienced Sjogren-Larsson syndrome (SLS) with typical clinical signs. Examination of the brain revealed (1) accumulation of peculiar lipoid substances stained lightly with periodic acid-Schiff (PAS) in the subpial, subependymal, and perivascular glial layers, the subpial and perivascular spaces, and the white matter of the cerebrum and brainstem; (2) proliferation of perivascular macrophages containing lipofuscin-like pigments; (3) dense distribution of round or ellipsoid small bodies stained strongly with PAS in the subpial, subependymal, and perivascular glial layers and the white matter; (4) appearance of spheroid bodies in the neuropil of relay nuclei (the lateral geniculate body, pontine nuclei, inferior olivary nucleus, posterior funicular nucleus, and dentate nucleus) and the white matter; and (5) reduction of myelinated nerve fibers in the cerebral and cerebellar white matter. Six-layered neuronal cytoarchitecture was preserved in the cerebral neocortex, except for the insula where pyramidal neurons were arranged at random. The exact mechanisms remain unclear, but it is suggested that peculiar lipoid substances may accumulate in the specific regions of the brain and that neuronal and astrocytic processes may be primarily affected in SLS.

Brain↗
PubMed1998

Enhanced NOR-1 gene expression by exposure of Chinese hamster cells to high-density 50 Hz magnetic fields.

Enhanced expression of neuron derived orphan receptor (NOR-1) gene was observed by exposure of Chinese hamster ovary K1 (CHO-K1) cells to an extremely low frequency magnetic field (ELFMF) of 50 Hz at 400 mT, but not at 5 mT. The enhanced expression, reaching the maximum at 6 h, was transient and reduced to the control level after exposure to 400 mT ELFMF for 24 h. The NOR-1 expression induced by treatment with forskolin and TPA was further enhanced by the simultaneous treatment with 400 mT ELFMF, in which the maximum response was at 3 h. The NOR-1 expression by these treatments was induced more earlier than that by 400 mT ELFMF alone. When cells were treated with an inhibitor of the protein kinase C (calphostin C or crocetin) and Ca2+ entry blockers (nifedipin and dantrolen) during the 400 mT ELFMF exposure, the enhanced NOR-1 expression was not observed. Exposure of CHO-K1 cells to the high-density 400 mT ELFMF may affect the signal transduction in the cells, resulting in the enhanced NOR-1 gene expression.

Animals↗
PubMed1998

Short-term and long-term pancreatic exocrine and endocrine functions after pancreatectomy.

Exocrine and endocrine functions of the pancreas were assessed in 44 Japanese patients who underwent pancreatic head resection. Functions were analyzed comparing levels before surgery, at a short-term follow-up (<2 months), and at a long-term follow-up (12-31 months). The N-benzoyl-L-tyrosyl-p-aminobenzoic acid (BT-PABA) excretion test, fasting blood sugar (FBS) level, and oral glucose tolerance test (OGTT) were used to determine pancreatic function. The patients were divided into three groups according to the size of the main pancreatic duct: group 1, 15 patients with a normal sized duct (< or =3 mm); group 2, 20 with a moderately dilated duct (>3 mm, <10 mm); and group 3, 9 with a markedly dilated duct (> or =10 mm). The mean BT-PABA value (6-hr urinary PABA recovery rate) in group 1 showed no change during the postoperative period. In contrast, the BT-PABA values in groups 2 and 3 had dropped by the short-term follow-up and returned to the preoperative level by the long-term examination. FBS and 120-min OGTT levels were not different between the three groups preoperatively. Although these values showed no change in all the three groups at the short-term measurements, the FBS in group 3 and 120-min levels in all the three groups had increased at the long-term. These findings suggest that exocrine pancreatic function shows a short-term deterioration in patients with a dilated pancreatic duct but recovers to the preoperative level over the long term after pancreatic head resection. Endocrine insufficiency, however, may occur at a long-term point after surgery irrespective of the preoperative pancreatic ductal dilatation.

4-Aminobenzoic Acid↗
PubMed1998

The significance of specific IgG4 antibodies to methyltetrahydrophthalic anhydride in occupationally exposed subjects.

BACKGROUND: A definitive role for allergen-specific IgG4 as either an anaphylactic or a blocking antibody, or both, remains controversial. OBJECTIVE: A population of 148 workers from two condenser plants (A and B) using epoxy resin with methyltetrahydrophthalic anhydride (MTHPA) was studied to evaluate the significance of MTHPA-specific IgG4 antibody. METHODS: The workers were evaluated through questionnaire and serological investigations. RESULTS: Ninety-seven (66%) of the currently exposed workers had positive MTHPA-specific IgE. IgE-sensitized workers in each plant had significantly more eye and nose complaints than unsensitized workers (P < 0.03). As the result of multiple logistic analysis, specific IgE antibodies was the most important predictor of work-related symptoms and its effect was greater than that of specific IgG4 (odds ratio 16.7 and 3.68, respectively). These indicate an IgE-mediated mechanism in most cases of work-related symptoms associated with MTHPA exposure. However, it cannot be denied that specific IgG4 is an anaphylactic antibody. Furthermore, IgE-sensitized workers in these plants displayed work-related symptoms despite the presence of specific IgG4. The frequency of positive specific IgG4 in continuously exposed workers was significantly (P < 0.02) higher in plant A than in plant B, reflecting the difference of the MTHPA levels between the two plants. In plant A, the frequency of positive specific IgG4 was significantly (P < 0.002) higher in continuously exposed workers than in intermittently exposed workers. Multiple regression analysis also confirmed that plant and exposure style contributed significantly (P < 0.01) to the determination of specific IgG4 levels. CONCLUSION: These results suggest that work-related eye and nasal symptoms are likely to be IgE-mediated, and that specific IgG4 may reflect the intensity of MTHPA exposure and may not act as a blocking antibody.

Adult↗
PubMed1998

Correlation between antigen-specific IL-2 response test and provocation test for egg allergy in atopic dermatitis.

BACKGROUND: The antigen-specific interleukin-2 response (AIR) test using lymphocytes is effective in searching for the antigen which causes allergic diseases and understanding their disease activity. OBJECTIVE AND METHODS: The correlation between the raw egg oral provocation test and egg white antigen-specific interleukin-2 (IL-2) response test was investigated in 123 children with infantile atopic dermatitis and 13 children with bronchial asthma. RESULTS: Among the 83 who showed positive reactions to provocation, 75 also reacted positively to the AIR test (sensitivity, 90.4%), while among the 53 children who showed negative responses to antigen provocation, 45 produced negative responses to the AIR test (specificity, 84.9%). The specificity of egg white IgE RAST score and skin-prick test are 88.7 and 81.3% which are comparable to that of the AIR test. However, their sensitivity was low (38.6 and 66.7%). In the patterns of symptom developed in the provocation AIR displayed late and delayed type allergic responses in addition to the immediate type which RAST reflected. The RAST-negative group composed of 98 patients included 51 (52.0%) who exhibited positive reactions to the provocation test. Among these 44 responded positively to the AIR test (86.3%). CONCLUSION: The AIR test is effective for screening egg white antigen as part of the tests for antigens responsible for allergic diseases and as a test to ascertain the relevant antigens, and that the conditions that could not be diagnosed by RAST can be detected by the AIR test.

Administration, Oral↗
PubMed1998

BRAM1, a BMP receptor-associated molecule involved in BMP signalling.

BACKGROUND: TGF-beta superfamily members elicit signals through the stimulation of serine/threonine-kinase receptors. Recently, molecules associated with several TGF-beta family receptors have been cloned. One such molecule, the immunophilin FKBP12, has been reported to interact with TGF-beta family type I receptors. However, the identity of signalling specific molecules interacting with the receptor was unknown. RESULTS: To clarify the factors mediating bone morphogenetic protein (BMP) receptor signalling, a cytoplasmic molecule associated with the BMP type IA receptor (BMPR-IA) was isolated using the yeast two-hybrid system. We designated the molecule BMP receptor associated molecule 1 (BRAM1). BRAM1 is an alternatively spliced form of BS69, a factor previously identified as an adenovirus E1A-associated protein. BRAM1 was localized to the cytoplasmic region in mammalian cells, whereas BS69 is localized to the nucleus. BRAM1 bound specifically to BMPR-IA in mammalian cells. The C-terminal half of BRAM1 was found to be sufficient for binding to BMPR-IA. CONCLUSIONS: BRAM1, a BMPR-IA associated molecule, was isolated using the yeast two-hybrid system, and found to associate specifically with BMPR-IA. BRAM1 may thus serve as an interacting protein in the BMP signal pathway.

Adaptor Proteins, Signal Transducing↗