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Biomedical subjects

Y Kishi

Publications and source records attributed to Y Kishi.

At least 19 recordsLinked to original sources
PubMed2007

Autotaxin (NPP-2) in the brain: cell type-specific expression and regulation during development and after neurotrauma.

Autotaxin is a secreted cell motility-stimulating exo-phosphodiesterase with lysophospholipase D activity that generates bioactive lysophosphatidic acid. Lysophosphatidic acid has been implicated in various neural cell functions such as neurite remodeling, demyelination, survival and inhibition of axon growth. Here, we report on the in vivo expression of autotaxin in the brain during development and following neurotrauma. We found that autotaxin is expressed in the proliferating subventricular and choroid plexus epithelium during embryonic development. After birth, autotaxin is mainly found in white matter areas in the central nervous system. In the adult brain, autotaxin is solely expressed in leptomeningeal cells and oligodendrocyte precursor cells. Following neurotrauma, autotaxin is strongly up-regulated in reactive astrocytes adjacent to the lesion. The present study revealed the cellular distribution of autotaxin in the developing and lesioned brain and implies a function of autotaxin in oligodendrocyte precursor cells and brain injuries.

Animals↗
PubMed2006

Clinicopathological features of pyothorax-associated lymphoma; a retrospective survey involving 98 patients.

To investigate clinicopathological features of pyothorax-associated lymphoma (PAL), we examined medical records of 98 patients (88 males and 10 females) with PAL at a median age of 70 years (range 51-86). Seventy-nine patients had a history of artificial pneumothorax. Median interval between diagnosis and artificial pneumothorax was 43 years (range 19-64). At diagnosis, performance status (PS) was 0-1 (n=56) and 2-4 (n=42). Clinical stages were I (n=42), II (n=26), III (n=8) and IV (n=22). Pathological diagnosis comprised diffuse large-B-cell (n=78) and peripheral T-cell lymphoma (n=1). Seventeen were treated supportively. The other 81 received aggressive treatments; chemotherapy (n=52), radiotherapy (n=7), surgery (n=4) and combination (n=18). Five-year overall survival (OS) was 0.35 (95% confidence interval, 24% to 45%). Causes of deaths were PAL (n=39), respiratory failure (n=13) and others (n=12). Multivariate analysis identified prognostic factors for OS; lactate dehydrogenase levels [hazard ratio (HR)=2.36; P=0.013], sex (female versus male) (HR=0.15; P=0.01), PS (2-4 versus 0-1) (HR=2.20; P=0.02), clinical stages (III/IV versus I/II) (HR=1.95; P=0.037) and chemotherapy (HR=0.31; P=0.01). Most patients with PAL are elderly and have comorbidities, while some of them achieve durable remission with appropriate treatments. These findings prompt us to establish an optimal treatment strategy on the basis of risk stratification of individual patients.

Aged↗
PubMed2006

Preoperative estimation of right lateral sector graft by three-dimensional computed tomography.

The right lateral sector is an alternative graft for living donor liver transplantation. Three-dimensional image reconstruction of right lateral sector grafts was performed to reveal vascular anatomy and volume using three-dimensional computed tomography software in three donors. There was a correlation between actual and estimated volume (r=.93), although actual graft volume tended to be larger than the preoperative estimated volume. In one donor, a portal branch of the right lateral sector was independently ramified. The branch was sacrificed in the operation because its territory volume was only 44 cm3. Three-dimensional images matched the shape of the right lateral sector graft. Three-dimensional computed tomography might be useful before donor hepatectomy, providing important information for decisions regarding the operative procedure.

Humans↗
PubMed2006

New-onset diabetes mellitus after living donor liver transplantation: possible association with hepatitis C.

BACKGROUND: The relationship between hepatitis C virus (HCV) infection and new-onset diabetes mellitus (NODM) after liver transplantation is a controversial issue. METHODS: A total of 223 adult living donor liver transplantation (LDLT) recipients followed for more than 6 months were analyzed for the prevalence of NODM. The prevalence was compared between 62 HCV-positive and 161 HCV-negative patients. All the HCV-positive patients underwent preemptive antiviral treatment with interferon alpha2b and ribavirin. RESULTS: Preoperative diabetes mellitus was more frequently observed in HCV-positive patients (18% vs 4%, P = .001). NODM occurred more frequently in HCV-positive patients (41% vs 22%, P = .003). Multivariate analysis, however, revealed that HCV was not a predictor for NODM. A comparison of 14 HCV-positive patients with persistent NODM and 48 patients without persistent NODM indicated that there was no significant difference in the frequency of the viral response to antiviral therapy nor in HCV-RNA levels. Impaired glucose tolerance did not impact postoperative survival after LDLT. CONCLUSIONS: HCV was not associated with the prevalence of NODM after LDLT. NODM did not influence patient survival.

Adult↗
PubMed2005

Relation between the middle hepatic vein drainage area volume and alanine aminotransferease after left liver harvesting.

Complete outflow is impossible to maintain on both sides in donors undergoing hemiliver graft harvesting, because the middle hepatic vein (MHV) can be preserved on only one side. The area in which outflow veins are disrupted becomes congested and does not sufficiently regenerate. The relation between changes in alanine aminotransferase (ALT) and the congestive area volume of the congestive area is unknown. The 64 subjects presented herein were living donors who provided the left liver with the caudate lobe and MHV trunk. The midpoint between the tributaries of the MHV and the right hepatic vein was determined preoperatively using computed tomography. The midpoint between the tributaries of the MHV and right hepatic vein and the borderline between the right and left liver were used to predict the MHV drainage area volume. ALT was measured in donors on postoperative days 1, 3, 5, 7, 10, and 14. The patients were divided into three groups according to the ratio of calculated MHV drainage area volume in the remnant right liver: less than 15% (n = 21, group A); greater than 15% and less than 20% (n = 18, group B); greater than 20% (n = 25, group C). There were significant differences in the ALT levels between groups (P = .004). MHV drainage area volume, calculated using the present method, was associated with high ALT levels after left liver harvesting with the MHV. The present study suggests that persistently high ALT levels are associated with the volume of the interrupted MHV drainage area.

Alanine Transaminase↗
PubMed2005

Long-term survival and causes of late graft loss after adult-to-adult living donor liver transplantation.

The vast amount of experience with deceased donor liver transplantation allows for the evaluation of the causes underlying late graft loss and the adoption of strategies for its prevention. In contrast, the long-term results or causes of late graft loss after adult-to-adult living donor liver transplantation have not been fully examined. Thus, we analyzed 176 adult recipients who survived at least 1 year after living donor liver transplantation. The median follow-up period was 33 months. Of the 176 recipients, eight died and three others underwent retransplantation. The most common cause of graft loss in our series was cholangitis (n = 4), which might be due partly to technical problems. The 3-year and 5-year patient survival rates of the subjects were 95% and 90%, respectively. Long-term survival after living donor liver transplantation was satisfactory in our series. Further improvement of surgical techniques for biliary reconstruction may reduce late graft loss.

Adult↗
PubMed2005

Reduced-intensity stem-cell transplantation for adult acute lymphoblastic leukemia: a retrospective study of 33 patients.

Efficacy of reduced-intensity stem-cell transplantation (RIST) for acute lymphoblastic leukemia (ALL) was investigated in 33 patients (median age, 55 years). RIST sources comprised 20 HLA-identical related donors, five HLA-mismatched related, and eight unrelated donors. Six patients had undergone previous transplantation. Disease status at RIST was first remission (n=13), second remission (n=6), and induction failure or relapse (n=14). All patients tolerated preparatory regimens and achieved neutrophil engraftment (median, day 12.5). Acute and chronic graft-versus-host disease (GVHD) developed in 45 and 64%, respectively. Six patients received donor lymphocyte infusion (DLI), for prophylaxis (n=1) or treatment of recurrent ALL (n=5). Nine patients died of transplant-related mortality, with six deaths due to GVHD. The median follow-up of surviving patients was 11.6 months (range, 3.5-37.3 months). The 1-year relapse-free and overall survival rates were 29.8 and 39.6%, respectively. Of the 14 patients transplanted in relapse, five remained relapse free for longer than 6 months. Cumulative rates of progression and progression-free mortality at 3 years were 50.9 and 30.4%, respectively. These findings suggest the presence of a graft-versus-leukemia effect for ALL. RIST for ALL is worth considering for further evaluation.

Adolescent↗
PubMed2005

Value of surveillance blood culture for early diagnosis of occult bacteremia in patients on corticosteroid therapy following allogeneic hematopoietic stem cell transplantation.

Bloodstream infection (BSI) is a significant complication following allogeneic hematopoietic stem cell transplantation (allo-SCT). Corticosteroids mask inflammatory responses, delaying the initiation of antibiotics. We reviewed medical records of 69 allo-SCT patients who had been on >0.5 mg/kg prednisolone to investigate the efficacy of weekly surveillance blood cultures. A total of 36 patients (52%) had positive cultures, 25 definitive BSI and 11 probable BSI. Pathogens in definitive BSI were Staphylococcus epidermidis (n=7), S. aureus (n=4), Entrococcus faecalis (n=3), Pseudomonas aeruginosa (n=5), Acenitobacter lwoffii (n=4), and others (n=10). The median interval from the initiation of corticosteroids to the first positive cultures was 24 days (range, 1-70). At the first positive cultures, 15 patients with definitive BSI were afebrile. Four of them remained afebrile throughout the period of positive surveillance cultures. Patients with afebrile BSI tended to be older (P=0.063), and had in-dwelling central venous catheters less frequently than febrile patients (P<0.0001). Bloodstream pathogens were directly responsible for death in two patients with afebrile BSI. This study demonstrates that cortisosteroid frequently masks inflammatory reactions in allo-SCT recipients given conrticosteroids, and that surveillance blood culture is only diagnostic clue for 'occult' BSI.

Adolescent↗
PubMed2005

Optimal initial dose of oral cyclosporine in relation to its toxicities for graft-versus-host disease prophylaxis following reduced-intensity stem cell transplantation in Japanese patients.

Since the introduction of reduced-intensity stem-cell transplantation (RIST), allogeneic stem-cell transplantation has become available for elderly patients. While pharmacokinetics of cyclosporine might differ according to age or other factors, cyclosporine is uniformly started at an oral dose of 6 mg/kg/day. We retrospectively reviewed medical records of 35 patients aged between 32 and 65 (median 52) years who had undergone RIST. Doses of cyclosporine were adjusted to the target blood trough level of 150-250 ng/ml. Cyclosporine dosages were changed in 33 patients (94%). Dose reduction was required in 32 patients because of high blood levels (n=25), renal dysfunction (n=3), hepatic dysfunction (n=2), and hypertension (n=2). Cyclosporine doses were increased in one because of the suboptimal level. The median of the achieved stable doses was 3.1 mg/kg/day (range, 1.0-7.4). Five patients sustained Grade III toxicities according to NCI-CTC version 2.0: renal dysfunction (n=4), hyperbilirubinemia (n=2), and hypertension (n=2). No patients developed grade IV toxicity. There was no statistically significant difference in the frequency and severity of cyclosporine toxicities between patients aged 50 years and above and those below 50 years. The initial oral cyclosporine dose of 6 mg/kg/day was unnecessarily high irrespective of age. The possible overdose of cyclosporine might have aggravated regimen-related toxicities.

Administration, Oral↗
PubMed2005

Reduced-intensity hematopoietic stem-cell transplantation for malignant lymphoma: a retrospective survey of 112 adult patients in Japan.

We conducted a nation-wide survey of 112 adult Japanese patients who underwent reduced-intensity stem cell transplantation (RIST) from 1999 to 2002. Underlying diseases included indolent (n=45), aggressive (n=58) and highly aggressive lymphomas (n=9). Median age of the patients was 49 years. A total of 40 patients (36%) had relapsed diseases after autologous stem cell transplantation and 36 patients (32%) had received radiotherapy. RIST regimens were fludarabine-based (n=95), low-dose total body irradiation-based (n=6) and others (n=11). Cumulative incidences of grade II-IV acute graft-versus-host disease (GVHD) and chronic GVHD were, respectively, 49 and 59%. Cumulative incidences of progression and progression-free mortality were 18 and 25%, respectively. With a median follow-up of 23.9 months, 3-year overall survival rates were 59%. A multivariate analysis identified three significant factors for progression, which are history of radiation (relative risk (RR) 3.45, confidential interval (CI) 1.12-10.0, P=0.03), central nervous system involvement (RR 6.25, CI 2.08-20.0, P=0.001) and development of GVHD (RR 0.28, CI 0.090-0.86, P=0.026). RIST may have decreased the rate of transplant-related mortality, and GVHD may have induced a graft-versus-lymphoma effect. However, whether or not these potential benefits can be directly translated into improved patient survival should be evaluated in further studies.

Adult↗
PubMed2005

Intestinal thrombotic microangiopathy following reduced-intensity umbilical cord blood transplantation.

Thrombotic microangiopathy (TMA) is a significant complication after hematopoietic stem-cell transplantation (HSCT); however, there is little information on it following reduced-intensity cord blood transplantation (RI-CBT). We reviewed the medical records of 123 adult patients who received RI-CBT at Toranomon Hospital between January 2002 and August 2004. TMA was diagnosed in seven patients based on intestinal biopsy (n = 6) or autopsy results (n = 1). While these patients showed some clinical symptoms such as diarrhea and/or abdominal pain, mental status alterations or neurological disorders were not observed in any of them. Laboratory results were mostly normal at the onset of TMA; >2% fragmented erythrocytes (n = 1), <10 mg/dl haptoglobin (n = 1), and >200 IU/dl lactic dehydrogenase (LD) (n = 4). On endoscopic examination, TMA lesions, consisting of ulcers, erosions, and diffuse exfoliation, were distributed spottily from terminal ileum to rectum. Intestinal graft-versus-host disease (GVHD) and cytomegalovirus (CMV) colitis were confirmed in five and four patients, respectively. With therapeutic measures including supportive care (n = 4), fresh frozen plasma (n = 1), and a reduction of immunosuppressive agents (n = 1), TMA improved in four patients. The present study demonstrates that intestinal TMA is a significant complication after RI-CBT. Since conventional diagnostic criteria can overlook TMA, its diagnosis requires careful examination of the gastrointestinal tract using endoscopy with biopsy.

Adolescent↗
PubMed2005

Comparison between reduced intensity and conventional myeloablative allogeneic stem-cell transplantation in patients with hematologic malignancies aged between 50 and 59 years.

To evaluate the efficacy of reduced-intensity stem-cell transplantation (RIST), we retrospectively compared outcomes of 207 consecutive Japanese patients aged between 50 and 59 years with hematologic malignancies who received RIST (n=70) and conventional stem-cell transplantation (CST) (n=137). CST recipients received total body irradiation (TBI)-based or busulfan/cyclophosphamide-based regimens. RIST regimens were purine analog-based (n=67), 2 Gy TBI-based (n=2), and others (n=1). Most CST recipients (129/137) received calcineurin inhibitors and methotrexate as graft-versus-host (GVHD) prophylaxis, while 32 RIST recipients received cyclosporin. In all, 23 CST and five RIST recipients died without disease progression within 100 days of transplant. Grade II to IV acute GVHD occurred in 56 CST and 38 RIST recipients. There was no significant difference in overall survival (OS) and progression-free survival between CST and RIST. On multivariate analysis on OS, five variables were significant: preparative regimens (CST vs RIST) (hazard ratio=1.92, 95% confidence interval, 1.25-2.97; P=0.003), performance status (2-4 vs 0-1) (2.50, 1.51-4.16; P<0.001), risk of underlying diseases (1.85, 1.21-2.83; P=0.004), acute GVHD (2.57, 1.72-3.84; P<0.001), and CML (0.38, 0.21-0.69; P=0.002). We should be careful in interpreting results of this small-sized retrospective study; however, reduced regimen-related toxicity might contribute to better survival in RIST. The low relapse rates following RIST suggest a strong antitumor activity through allogeneic immunity.

Female↗
PubMed2005

Cryptococcosis after living donor liver transplantation: report of three cases.

Cryptococcosis is the third most common invasive fungal infection in solid organ transplantation, which usually occurs more than 6 months after the primary operation. In our series of 180 consecutive adult living-donor liver transplantation recipients, three (1.5%) had cryptococcosis and one of these patients died. The serum cryptococcal antigen examination was positive in all three patients who suffered from cryptococcosis. The serum cryptococcal antigen test might contribute to the early detection and treatment of cryptococcosis.

Aged↗