Search PubMed⌕ Search

Biomedical subjects

K Fujimori

Publications and source records attributed to K Fujimori.

At least 19 recordsLinked to original sources
PubMed2006

Continuous low-dose human atrial natriuretic peptide promotes diuresis in oliguric patients after living donor liver transplantation.

Human atrial natriuretic peptide (ANP) is beneficial for the prophylaxis of acute renal failure (ARF) after liver transplantation (OLT). We evaluated renal function in OLT patients with or without ARF, describing cases unresponsive to loop diuretics successfully treated with continuous low-dose ANP infusion without hemodialysis. Twenty-seven consecutive adult-to-adult living donor liver transplantations (LDLTs) were performed in 26 patients. One case was excluded due to the need for continuous hemodialysis (HD) during the operation. Of the 26 cases, 6 (23%, group 2) developed ARF in the first 30 days after LDLT; the other 20 were ARF-free (group 1). The median follow-up was 24 months. No patient required either continuous or intermittent HD. Only one patient died due to multiple liver abscesses. Mean preoperative serum creatinine (sCr) value and intraoperative blood loss in group 2 were significantly higher than those in group 1. Three cases in group 2 failed to improve on high-dose loop diuretics with low-dose dopamine, exhibiting fluid overload. The remaining three cases in group 2 responded to conventional diuretic treatments. Continuous low-dose ANP was started 2, 4, or 5 days after LDLT, and urine output significantly increased after ANP administration. The serum creatinine values were 1.1, 1.2, and 1.1 at 1 month and 1.0, 0.9, and 0.6 mg/dL at 6 months after LDLT. Massive blood loss during the operation caused ARF, but did not affect renal function after LDLT. Continuous low-dose ANP improved renal function and diuresis for oliguric ARF patients, preventing the need for HD or continuous venovenous hemodialysis.

Adult↗
PubMed2005

Effect of Helicobacter pylori eradication on ongoing mutation of immunoglobulin genes in gastric MALT lymphoma.

Gastric low-grade mucosa-associated lymphoid tissue (low-grade MALT) lymphomas has been associated with Helicobacter pylori (H. pylori) infection. Although infiltrating T cells with specificity for H. pylori are known to stimulate the development of MALT lymphomas, the effect of H. pylori eradication on rearranged immunoglobulin heavy chain (IgH) genes of low-grade gastric MALT lymphomas is unclear. Gastric biopsies from five cases were investigated by cloning and sequence analysis of rearranged IgH genes before and after the treatment for H. pylori. In all cases, IgH genes were mutated from their germline counterpart. The frequency of intraclonal sequence heterogeneity before the eradication of H. pylori varied from 0.25 to 0.49%. Clones obtained from the tumours before the eradication of H. pylori in cases 1 and 2 showed a tendency to display a mutation pattern by positive antigen selection and their monoclonarity disappeared after the eradication. The frequency of intraclonal sequence heterogeneity of the clones obtained from cases 3, 4 and 5 (0.12% in case 3, 0.10% in 4 and 0.18% in 5) after the eradication of H. pylori was lower than that in tumours before the eradication (0.30% in case 3, 0.49% in 4 and not determined in 5). These findings suggest that low-grade gastric MALT lymphomas expand due to the persistent presence of H. pylori in vivo. The characteristic feature of tumour clones obtained from the tumours after the eradication of H. pylori is a very low intraclonal heterogeneity, which may potentially be independent of H. pylori.

Aged↗
PubMed2005

New strategy for ABO-incompatible living donor liver transplantation with anti-CD20 antibody (rituximab) and plasma exchange.

It is more difficult to control humoral rejection in living donor liver transplantations (LDLT) across the ABO blood group barrier than in matched or compatible combinations. We achieved excellent results in ABO-incompatible transplantation with novel immunosuppressive regimens and plasma exchange (PE). Among 82 LDLT were 10 cases of ABO-incompatible recipients, including three who were administered rituximab for rescue or prophylactic therapy. Pretransplantation PE was performed as necessary to maintain hemagglutinin titers below 1:16 and posttransplantation PE was performed when there were signs of hyperacute rejection associated with high titers. Induction immunosuppression consisted of FK506, steroid, mycophenolate mofetil (MMF), and rituximab. The first patient was administered rituximab with deoxyspergualin (DSG), steroid pulse therapy, and PE on postoperative day (POD) 7, because of biopsy-proven humoral acute rejection. The titers and LFTs improved drastically. The second and third patients were administered rituximab just after the operation with other routine immunosuppressants for prophylaxis of hyperacute rejection. The second patient showed a slight deterioration in LFTs with an elevated titer, which normalized after steroid pulse therapy and PE. The third patient had no episodes of rejection. At present, that is 27, 17, and 6 months after the operations respectively, the 3 transplant recipients are in stable condition.

ABO Blood-Group System↗
PubMed2005

Experience with recipient's superficial femoral vein as conduit for middle hepatic vein reconstruction in a right-lobe living donor liver transplant procedure.

Middle hepatic vein reconstruction during the right-lobe living donor liver transplant procedure has been recognized to be a significant factor. We initially reconstructed only a single middle hepatic vein orifice draining into segment 8. In cases where the right-lobe liver graft has several major middle hepatic vein tributaries, including veins draining segment 5 that are remote from the right hepatic vein orifice, a long and thick interposition conduit is necessary for reconstruction. Among 11 consecutive adult patients who received a right-lobe liver graft without a middle hepatic vein at our institution, 8 underwent reconstruction of all major middle hepatic vein tributaries using a vein graft from the recipient's superficial femoral vein. The remaining 3 patients had no major middle hepatic vein tributaries. Posttransplant-computed tomography imagings showed increased liver mass with a patent superficial femoral vein graft in 8 patients. In the absence of a venous system from a deceased donor, a recipient superficial femoral vein offers an excellent size match to maintain the venous outflow of middle hepatic vein tributaries. Reconstruction with recipient superficial femoral vein plays an important role in maximizing liver function and minimizing morbidity in the early posttransplant period.

Adult↗
PubMed2005

A clinical study of Japanese patients with ulcer induced by low-dose aspirin and other non-steroidal anti-inflammatory drugs.

BACKGROUND: The incidence and severity of non-steroidal anti-inflammatory drugs (NSAIDs)-induced gastro-duodenal ulcer have not been extensively studied in Japan. AIM: We performed a prospective study to clarify NSAIDs-induced gastro-duodenal injury, focusing especially on low-dose aspirin (L-A). METHODS: Two hundred and thirty-eight patients with bleeding peptic ulcers admitted to our hospital. History of taking NSAIDs and anti-ulcer drugs was obtained from all patients who underwent endoscopic examinations. The lesion scores of patients taking L-A were classified numerically from zero (no lesion) to five (ulcer). RESULTS: The NSAIDs were associated with 28.2% of hemorrhagic ulcers. The rates of patients using L-A, loxoprofen, diclofenac, and combination of two of these drugs were 27, 16, 10 and 9%, respectively. Co-administered anti-ulcer drugs were cytoprotective anti-ulcer drugs (27%), H2 receptor antagonists (16%), PPI (4%), and none (53%). In patients taking L-A, H2 receptor antagonists were used most frequently. The HP was positive in 63% of L-A-induced ulcer cases and in 69% of NSAIDs other than low-dose aspirin-induced ulcer cases. The lesion scores of patients taking L-A with H2 receptor antagonists or PPI were significantly lower than those of patients who were taking only L-A (P < 0.05). CONCLUSIONS: Approximately one-third of hospitalized patients with NSAIDs-induced hemorrhagic ulcer showed an association with L-A. Prospective randomized controlled trials including H2 receptor antagonists are required to establish preventive efforts aimed at L-A-induced gastro-duodenal injury.

Adult↗
PubMed2004

The effects of veno-venous extracorporeal membrane oxygenation on hypoxic fetal lambs.

OBJECTIVE: The purpose of this study was to determine the applicability of veno-venous extracorporeal membrane oxygenation (V-V ECMO) to support fetal oxygenation in utero. METHODS: An ECMO system with a centrifugal pump was applied to ten chronically instrumented fetal lambs, at 126 or 127 days of gestation. Blood was obtained through a double-lumen catheter inserted into the right atrium. After oxygenation, the blood was returned through a single-lumen catheter into either the carotid artery (veno-arterial; V-A ECMO) or the right atrium (V-V ECMO). After fetal hypoxia had been experimentally produced, V-A ECMO or V-V ECMO was instituted to maintain fetal oxygenation. We compared fetal blood gases with both routes of ECMO. RESULTS: Oxygen partial pressure (pO(2)) in the fetal cranial carotid artery decreased to 12.9 +/- 0.6 mmHg after reducing the fraction inspiratory oxygen of the mother. After instituting V-A ECMO, pO(2) was found to be 23.5 +/- 2.6 mmHg; after instituting V-V ECMO, pO(2) was found to be 20.3 +/- 1.9 mmHg. Thus, fetal acidosis increased under both procedures. Fetal heart rate and blood pressure were not altered significantly during the experiments. CONCLUSIONS: This study indicates that V-V ECMO could more effectively and less traumatically maintain oxygenation in hypoxic fetal lambs.

Animals↗
PubMed2004

The natural history of maternal immunization against foetal platelet alloantigens.

Foetomaternal alloimmune thrombocytopenia (FMAIT) occurs when maternal antibodies of an antigen-negative mother cause destruction of sensitized foetal platelets. In Caucasian populations, 6-12% of human platelet antigen (HPA)-1a-negative women develop anti-HPA-1a, and the incidence of clinically affected cases is estimated to be 10-20% of immunized women. This study was performed in order to elucidate the rate of maternal immunization, incidence of FMAIT and the likely outcome of the condition in Asians. Excluding two or more pregnancies during the period, serum samples from 24 630 pregnant women, mainly Japanese, were screened for antibodies against platelet alloantigens by means of mixed passive haemagglutination (MPHA) (Anti-HPA-MPHA, Olympus, Tokyo). Antibodies were detected in 0.91% (223/24 630) of the women's samples and the immunization rate was correlated with the number of pregnancies. Antibody specificity included anti-HPA-4b (49), anti-HPA-5a (three), anti-HPA-5b (168), anti-HPA-4b + 5b (one) and anti-Nak(a) (CD36) (two). No alloimmunization was observed within the HPA-1, HPA-2, HPA-3 or HPA-6 systems. Among HPA-4b- or HPA-5b-negative women, 24% or 14% estimated, respectively, had antibodies and 26% (10/38) or 10% (12/125) of neonates, respectively, born to these mothers developed thrombocytopenia. Two neonates born to mothers having anti-HPA-4b developed generalized purpura. No cases of intracranial bleeding or death due to FMAIT were recorded. Generalized purpura due to FMAIT occurs in one in 9359 (95% CI: 1 in 77 519-1 in 2591) pregnancies solely because of HPA-4b incompatibility.

Antigens, Human Platelet↗
PubMed2002

The clinical significance of colonoscopy in hemorrhagic colitis due to enterohemorrhagic Escherichia coli O157:H7 infection.

BACKGROUND AND STUDY AIMS: Although hemorrhagic colitis due to enterohemorrhagic Escherichia coli O157:H7 (O157) infection has recently attracted increasing attention as an important enteric infection, the colonoscopic findings associated with this disease have not been sufficiently characterized. The aim of this study is to characterize the colonoscopic features of hemorrhagic colitis due to O157 infection. PATIENTS AND METHODS: The colonoscopic findings in ten patients with hemorrhagic colitis due to O157 infection were retrospectively reviewed. To assess the severity of inflammation in each part of the large intestine, colonoscopic findings were categorized into four grades: grade 1, intact mucosa; grade 2, sporadic erythema and erosion; grade 3, mostly diffuse inflammation; and grade 4, diffuse, severe inflammation. RESULTS: Eight out of ten patients had grade 4 findings in the cecum and ascending colon, grade 3 in the transverse colon and descending colon, and grade 2 in the sigmoid colon. Two of these eight patients also had grade 4 inflammation in the proximal transverse colon. Five of these eight patients revealed longitudinal ulcer-like lesions in the transverse colon and/or descending colon. The remaining two patients had grade 3 findings in the cecum to the descending colon and grade 2 findings in the sigmoid colon. All patients exhibited grade 1 finding in the terminal ileum and the rectum. Based on these colonoscopic findings, the ten patients were divided into the typical group (eight patients) and the mild-type group (two patients). CONCLUSIONS: The characteristic colonoscopic findings in most patients with hemorrhagic colitis due to O157 infection were as follows: 1) severe inflammation, including primarily marked edema and facile hemorrhage, and 2) inflammation predominating at the right-side colon; and 3) frequent appearance of longitudinal ulcer-like lesions.

Adolescent↗
PubMed2001

Coupling between cyclooxygenase, terminal prostanoid synthase, and phospholipase A2.

We have recently shown that two distinct prostaglandin (PG) E(2) synthases show preferential functional coupling with upstream cyclooxygenase (COX)-1 and COX-2 in PGE(2) biosynthesis. To investigate whether other lineage-specific PG synthases also show preferential coupling with either COX isozyme, we introduced these enzymes alone or in combination into 293 cells to reconstitute their functional interrelationship. As did the membrane-bound PGE(2) synthase, the perinuclear enzymes thromboxane synthase and PGI(2) synthase generated their respective products via COX-2 in preference to COX-1 in both the -induced immediate and interleukin-1-induced delayed responses. Hematopoietic PGD(2) synthase preferentially used COX-1 and COX-2 in the -induced immediate and interleukin-1-induced delayed PGD(2)-biosynthetic responses, respectively. This enzyme underwent stimulus-dependent translocation from the cytosol to perinuclear compartments, where COX-1 or COX-2 exists. COX selectivity of these lineage-specific PG synthases was also significantly affected by the concentrations of arachidonate, which was added exogenously to the cells or supplied endogenously by the action of cytosolic or secretory phospholipase A(2). Collectively, the efficiency of coupling between COXs and specific PG synthases may be crucially influenced by their spatial and temporal compartmentalization and by the amount of arachidonate supplied by PLA(2)s at a moment when PG production takes place.

Arachidonic Acid↗
PubMed2001

Chemo-enzymatic synthesis of a bioactive peptide containing a glutamine-linked oligosaccharide and its characterization.

A bioactive peptide containing a glutamine-linked oligosaccharide was chemo-enzymatically synthesized by use of the solid-phase method of peptide synthesis and the transglycosylation activity of endo-beta-N-acetylglucosaminidase. Substance P, a neuropeptide, is an undecapeptide containing two L-glutamine residues. A substance P derivative with an N-acetyl-D-glucosamine residue attached to the fifth or sixth L-glutamine residue from the N-terminal region was chemically synthesized. A sialo complex-type oligosaccharide derived from a glycopeptide of hen egg yolk was added to the N-acetyl-D-glucosamine moiety of the substance P derivative using the transglycosylation activity of endo-beta-N-acetylglucosaminidase from Mucor hiemalis, and a substance P derivative with a sialo complex-type oligosaccharide attached to the L-glutamine residue was synthesized. This glycosylated substance P was biologically active, although the activity was rather low, and stable against peptidase digestion. The oligosaccharide moiety attached to the L-glutamine residue of the peptide was not liberated by peptide-N(4)-(N-acetyl-beta-D-glucosaminyl) asparagine amidase F.

Amidohydrolases↗
PubMed2001

Preferential X-chromosome inactivation in women with idiopathic recurrent pregnancy loss.

OBJECTIVE: To determine whether preferential X-chromosome inactivation (P-XCI) relates to idiopathic recurrent pregnancy loss. DESIGN: A retrospective study. SETTING: Infertility clinics and laboratory. PATIENT(S): Women with idiopathic recurrent pregnancy loss (group I), women who had given birth to children but with no history of spontaneous abortion (group II), and women without a history of pregnancy (group III). INTERVENTION(S): DNA samples from the heterozygotes for the (CAG)n polymorphism within the androgen receptor gene were modified with sodium bisulfite, PCR-amplified with primer pairs for methylated androgen receptor alleles (M-PCR) and unmethylated alleles (U-PCR), and subjected to electrophoresis. MAIN OUTCOME MEASURE(S): Band peak patterns and peak area sizes. RESULT(S): In group I, 7 (16.7%) of 42 heterozygotes exhibited P-XCI; four possessed single-peak patterns in the M-PCR and U-PCR products, and three had two-peak patterns in which the peak sizes differed considerably. In group II, 2 (5.6%) of 36 heterozygotes exhibited P-XCI as determined by the two-peak patterns. In group III, none of the 47 heterozygotes exhibited P-XCI. CONCLUSION(S): The incidence of P-XCI was statistically higher in group I than in the other groups. As P-XCI characterized by single-peak patterns was observed only in group I, such patterns, which may result from undiscovered cytogenetic or molecular abnormalities of the X-chromosome, likely correlate with pregnancy loss.

Abortion, Habitual↗
PubMed2001

Limited urinary concentration and damaged tubules in rats with a syngeneic kidney graft.

BACKGROUND: The underlying mechanisms of renal transplant dysfunction are poorly understood. There is little information on tubular function in kidney grafts. The cDNAs encoding kidney-specific cell surface proteins required for renal reabsorption of sodium (sodium cotransporter in thick ascending limb of Henle, rBSC1) and water (apical water channel in collecting duct, AQP2) have been recently identified. Since transcripts of these proteins are up-regulated in dehydration in association with maximal concentration of urine, we examined urinary concentrating ability and expression levels of mRNA of these proteins in kidney isografts. METHODS: Male Sprague-Dawley rats underwent syngeneic renal transplantation or unilateral nephrectomy (UNX) and were deprived of water for 24 hours at six weeks after the operation when histological and functional compensation of the intact kidney was complete. Blood and urinary samples were collected before and after dehydration. The amount of rBSC1 or AQP2 mRNA was measured using competitive polymerase chain reaction (PCR) by inducing a point mutation at the middle of PCR product for rBSC1 or by deleting 180 bp from 780 bp PCR product for AQP2, respectively. The protein expression was examined by Western blot analysis. RESULTS: Both groups of rats demonstrated the same levels of compensatory renal hypertrophy (approximately 60% weight increase) and plasma creatinine values. Histological examination revealed enlarged glomeruli and tubules, but no findings of ischemic damage, such as tubular atrophy or interstitial changes. Urinary concentration was noted in the UNX rats but not in rats with kidney grafts. Competitive PCR demonstrated that dehydration did not increase rBSC1 and AQP2 transcripts in rats with kidney transplantation. Immunoblot analysis confirmed that the marked increase of both rBSC1 and AQP2 proteins was noted only in the remnant kidney of dehydrated rats. CONCLUSIONS: Rats with kidney isografts have a limited capacity to concentrate urine and, at the same time, fail to increase rBSC1 and AQP2 transcripts. This suggests that there is a prolonged damage of renal tubules by ischemia or denervation of the donor kidney, both of which are inevitable in the transplantation procedure.

Animals↗
PubMed2001

Antibody elimination by apheresis in living donor liver transplant recipients.

In the present study, we investigated retrospectively the indications and the efficacy of the elimination of preexisting antiallogeneic antibodies in liver transplant recipients. Three patients who were ABO blood type incompatible were subjected to plasmapheresis and double filtration plasmapheresis before the living donor liver transplantation (LDLTx), and the titers decreased to less than 8. After transplantation, plasmapheresis was also performed in 3 cases, and continuous hemodiafiltration in 1 case, and in 2 out of these 3 patients acute rejection was recognized. Two patients who were crossmatch positive were subjected to plasmapheresis before transplantation, and the T warm titers were reduced to less than Score 2. These 2 patients had no acute rejections after transplantation. We conclude that in liver transplant patients apheresis is effective to prevent acute rejection induced by preexisting anti-A and/or anti-B antibodies and anti-donor specific antibodies before transplantation, but it is not effective in a patient with accelerated humoral rejection occurring after transplantation.

ABO Blood-Group System↗
PubMed2001

Experience with artificial liver support in 16 living related liver transplant recipients.

This study was a retrospective investigation about the indication and efficacy of artifical liver support for liver transplant recipients. Apheresis was performed in 16 of 41 patients subjected to living related liver transplantation (LRLTx) as articial liver support, including plasmapheresis (PP) in 13 cases, continuous hemodiafiltration (CHDF) in 7 cases, and plasma adsorption (PA) in 2 cases. One patient with cryptogenic liver cirrhosis was subjected to PP before the LRLTx, and the result was satisfactory. On the contrary, the results of PP and CHDF for graft, respiratory, or cardiac failure were not acceptable. Only 1 patient survived despite multiple organ failure. Both PP and PA for patients with hyperbilirubinemia were effective and improved their critical conditions. We conclude that apheresis for liver transplant patients is effective to treat hyperbilirubinemia, but it is not indicated for respiratory and cardiac failure nor for hepatic failure.

Adolescent↗
PubMed2001

Plasma endothelin-1 and atrial natriuretic peptide levels during prolonged (24-h) non-acidemic hypoxemia in fetal goats.

OBJECTIVE: The purpose of this study was to investigate the effects of prolonged (24-h) non-acidemic hypoxemia on plasma endothelin-1 and atrial natriuretic peptide (ANP) in fetal goats. METHODS: During continuous infusion of nitrogen into the maternal trachea, fetal plasma endothelin-1 and ANP levels were measured in nine chronically instrumented goat fetuses at 117-129 days' gestation. Endothelin-1 and ANP were measured by radioimmunoassay. RESULTS: Fetal arterial pO(2) decreased significantly from 23.1 +/- 1.0 mmHg (control) to 15.2 +/- 0.9 mmHg during the first 2 h of hypoxemia and to 15.7 +/- 1.1 mmHg at the end of the experimental period of hypoxemia. The plasma endothelin-1 concentration increased from 10.6 +/- 1.9 pg/ml to 20.4 +/- 4.3 pg/ml (p < 0.05) during the first 2 h and was 19.7 +/- 2.4 pg/ml (p < 0.01) at the end of the experimental period. The plasma ANP concentration also increased, from 20.3 +/- 5.5 pg/ml to 23.0 +/- 4.7 pg/ml in the first 2 h and then to 58.0 +/- 8.8 pg/ml (p < 0.05) at the end of the experimental period. There was a significant negative correlation between fetal plasma endothelin-1 and pO(2), but no significant correlation was found between fetal plasma ANP and pO(2). CONCLUSIONS: Prolonged non-acidemic hypoxemia induces a continuous increase in fetal plasma endothelin-1 and ANP levels. Fetal plasma ANP increases time-dependently but endothelin-1 remains constant during hypoxemia.

Animals↗
PubMed2001

Distribution of oxygenated blood flow at three different routes of extracorporeal membrane oxygenation in exteriorized fetal lambs.

OBJECTIVE: The purpose of this study was to determine which extracorporeal membrane oxygenation (ECMO) route best approximates the normal physiologic pattern of oxygenated blood distribution in fetal lambs submerged in warm saline solution. STUDY DESIGN: Six fetal lambs ranging from 113 to 129 days of gestation were delivered by cesarean section and oxygenated with ECMO in a warm saline solution bath. We compared the distribution of oxygenated blood flow during intact placental circulation with 3 routes of ECMO, from the right atrium to the carotid artery (V-A), from the right atrium to umbilical vein (V-UV), and from the right atrium with umbilical artery to umbilical vein [(V + UA)-UV], in exteriorized fetal lambs. Distribution of oxygenated blood flow was determined by nonradioactive colored microspheres. RESULTS: The ECMO blood flow rate through the catheters during V-A, V-UV or (V + UA)-UV ECMO ranged at 150 to 300 ml/min. Among the 3 different routes of ECMO, the oxygenated blood distribution in (V + UA)-UV showed the best correlation with placental-fetal blood flow, particularly in the brain and heart. CONCLUSION: This study indicated that (V + UA)-UV ECMO most closely approximates normal intact placental-fetal blood flow distribution in fetal lambs.

Animals↗