Safety Profile of the Concomitant Use of Atorvastatin and Cyclosporine in Renal Transplant Recipients.

Cyclosporine (CyA) and atorvastatin (AT) are often administered concomitantly to treat dyslipidemia in renal transplant recipients. However, CyA greatly increases the plasma concentration of AT; therefore, concomitant use might increase the frequency of statin-induced adverse effects. The aim of this study was to investigate whether concomitant use of CyA and AT increases intolerance of the latter agent in Japanese renal transplantation recipients. We performed a retrospective cohort analysis of renal transplant recipients aged 18 years and older who had concomitantly received AT and CyA, or tacrolimus (Tac) therapy. We defined statin intolerance as a decrease in dose or discontinuation of AT due to adverse effects. We evaluated the incidence of statin intolerance in concomitant therapy with CyA for 100 days after the initial administration of AT in comparison with Tac. A total of 144 renal transplant recipients who received AT and CyA, or Tac between January 2013 and December 2019 were included. There was no statistical difference in the incidence of statin intolerance in both the CyA (1.8%; 1/57 patients) and Tac (3.4%; 3/87 patients) groups. Concomitant use of CyA and AT might not increase the incidence of statin intolerance in Japanese renal transplant recipients.

Effects of postoperative dietary intake on functional recovery of patients undergoing cardiac surgery.

BACKGROUND AND AIM: Among elderly patients undergoing cardiac surgery, malnutrition is very common and related to muscle wasting known as sarcopenia. Cardiac surgery causes a further decline of nutritional status due to reduced dietary intake (DI); however, the impact of postoperative DI on functional recovery is unclear. METHODS AND RESULTS: We enrolled 250 consecutive patients undergoing cardiac surgery. Daily DI was measured between postoperative days 3 and 7. Patients were categorized as having sufficient or insufficient DI based on whether their DI met or was less than estimated total energy requirements. Functional capacity was measured using the 6-minute walking distance (6MWD) preoperatively and at discharge. Mean postoperative DI was 22.4 ± 3.0 kcal/kg/day, and postoperative DI was insufficient in 92 patients (36.8%). The prevalence of sarcopenia was not different by postoperative DI. Although there was no significant difference in preoperative 6MWD results (P = 0.65), the sufficient DI group had longer 6MWD at discharge than the insufficient DI group (P = 0.04). In multivariate regression analysis, preoperative poor nutritional status (ß = -0.29), duration of surgery (ß = -0.18), and postoperative DI (ß = 0.40) remained statistically significant predictors for improvement of 6MWD (P < 0.0001, adjusted R2 = 0.41). CONCLUSIONS: Postoperative DI was independently associated with functional recovery, but preoperative sarcopenia was not. Regardless of preoperative nutritional status or the presence of sarcopenia, aggressive nutritional intervention in the early stage after surgery helps support functional recovery.

Insulin degludec overdose may lead to long-lasting hypoglycaemia through its markedly prolonged half-life.

BACKGROUND: Overdose of insulin often causes long-lasting severe hypoglycaemia. Insulin degludec has the longest duration of action among the available insulin products; thus, an overdose of insulin degludec can lead to long-lasting hypoglycaemia. In the present paper, we report the case of a woman with long-lasting hypoglycaemia attributable to insulin degludec overdose and markedly prolonged insulin degludec half-life. CASE REPORT: A 64-year-old woman with Type 2 diabetes receiving insulin therapy was taken to an emergency department because of disturbed consciousness 21 h after self-injection of 300 units of insulin degludec (4.34 units/kg). Her plasma glucose level was 2.3 mmol/l. She received repeated intravenous boluses of dextrose for 43 h with continuous intravenous dextrose infusion, but no improvement in long-lasting hypoglycaemia or consciousness was observed. Considering the possibility of adrenal insufficiency, intravenous dexamethasone was administered, and her plasma glucose levels subsequently remained above 5.5 mmol/l without intravenous dextrose boluses. She gradually regained consciousness. A total of 34 h after the overdose, her plasma immunoreactive insulin levels were markedly increased and then gradually declined over ~400 h. The insulin degludec half-life was 40.76 h. CONCLUSION: Although the reported half-life of insulin degludec in the body is ~25 h when administered in standard doses (0.4-0.8 units/kg), no study has investigated its half-life after overdose. In the present case, the half-life of insulin degludec was ~1.6 times longer than that observed with standard doses, probably leading to long-lasting hypoglycaemia. Physicians should be aware of the possibility of unexpected long-lasting severe hypoglycaemia resulting from insulin degludec overdose.

Identification of thymidylate synthase as a potential therapeutic target for lung cancer.

BACKGROUND: Thymidylate synthase (TS), a key enzyme in the de novo synthesis of thymidine, is an important chemotherapeutic target for malignant tumours including lung cancer. Although inhibition of TS has an antiproliferative effect in cancer cells, the precise mechanism of this effect has remained unclear. METHODS: We examined the effects of TS inhibition with an RNA interference-based approach. The effect of TS depletion on the growth of lung cancer cells was examined using colorimetric assay and flow cytometry. RESULTS: Measurement of the enzymatic activity of TS in 30 human lung cancer cell lines revealed that such activity differs among tumour histotypes. Almost complete elimination of TS activity by RNA interference resulted in inhibition of cell proliferation in all tested cell lines, suggestive of a pivotal role for TS in cell proliferation independent of the original level of enzyme activity. The antiproliferative effect of TS depletion was accompanied by arrest of cells in S phase of the cell cycle and the induction of caspase-dependent apoptosis as well as by changes in the expression levels of cyclin E and c-Myc. Moreover, TS depletion induced downregulation of the antiapoptotic protein X-linked inhibitor of apoptosis (XIAP), and it seemed to activate the mitochondrial pathway of apoptosis. CONCLUSION: Our data provide insight into the biological relevance of TS as well as a basis for clinical development of TS-targeted therapy for lung cancer.

Mimicry of CD40 signals by Epstein-Barr virus LMP1 in B lymphocyte responses.

The effect of the Epstein-Barr virus (EBV) latent membrane protein 1 (LMP1) on the activation and differentiation of normal B cells was investigated. B cells of transgenic mice expressing LMP1 under the control of immunoglobulin promoter/enhancer displayed enhanced expression of activation antigens and spontaneously proliferated and produced antibody. Humoral immune responses of LMP1 transgenic mice in CD40-deficient or normal backgrounds revealed that LMP1 mimics CD40 signals to induce extrafollicular B cell differentiation but, unlike CD40, blocks germinal center formation. Thus, these specific properties of LMP1 may determine the site of primary B cell infection and the state of infection in the natural course of EBV infection, whereas subsequent loss of LMP1 expression may affect the site of persistent latent infection.

A Recurrent Epiphytotic of Guava Rust on Rose Apple, Syzygium jambos, in Hawaii.

A Neotropical rust of the Myrtaceae, Puccinia psidii Winter, was described from Psidium guajava L., or guava, in Brazil in 1884 (1). It was first discovered in Hawaii on potted Metrosideros polymorpha Gaud. on Oahu in April 2005 (2) with pathogenicity and identity established (3). It spread quickly, and by January 2006, severe outbreaks of this rust occurred statewide on new leaves of Syzygium jambos (L.) Alston, or rose apple. Rose apple, a native to South and Southeast Asia, was introduced to Hawaii in 1825 and is locally abundant to invasive from just above sea level to as high as 1,000 m in elevation in wet sites. Healthy, reddish green immature leaves on new twigs become deformed, yellow-red, and covered with masses of yellow urediniospores following infection. As the disease progresses, infected leaves are blackened and defoliate, with no functional leaves formed. Stem tips and branches are killed and the canopy becomes progressively smaller. Repeated mortality of juvenile leaves was observed to kill 8 to12 m tall trees in the Haiku area of Maui. Wind dispersal of urediniospores resulted in heavy infection of even small groups of S. jambos isolated by 1 km or more and billions of urediniospores covered the ground under diseased trees. On Hawaii, Maui, and Oahu, trees with many dead branches are becoming common with concerns about the fire hazard of these dead trees surrounded by dry grasses. At low humidity levels, or on more mature leaves characterized by soft expanded yellow-green tissue, fewer, mostly circular spots are formed that do not expand. S. jambos is an example of a highly vulnerable host in Hawaii and represents one of approximately 3,500 species of Myrtaceae outside the Neotropics growing in Australasia, Southeast Asia, the Pacific, and tropical Africa, which have evolved unexposed to P. psidii. Severely infected S. jambos plants have been the major source of spores in the environment, exposing many Myrtaceae hosts to P. psidii. The pathogenicity of P. psidii has been consistent among and within islands with S. jambos severely infected and M. polymorpha, Melaleuca quinquenervia, Rhodomyrtus tomentosa, Myrtus communis, and Eugenia species commonly infected. Other hosts such as S. cumini, S. malaccense, and Myriciaria cauliflora are also infected, although guava and Eucalyptus spp. are rarely infected. Strain differences within P. psidii are suspected (4). In the tropics, it is rare for mature trees to be killed by a foliar pathogen, but given the devastation of new growth, death of more S. jambos trees is likely. References: (1) T. A. Coutinho et al. Plant Dis. 82:819, 1998. (2) E. M. Killgore and R. A. Heu. New Pest Advisory No. 05-04. Hawaii Department of Agriculture, 2007. (3) J. Y. Uchida et al. Plant Dis. 90:524, 2006. (4) S. Zhong et al. Mol. Ecol. Res. 8:348. 2008.

A novel approach to successful ABO-incompatible high-titer renal transplantation.

BACKGROUND: Currently the long-term outcome among recipients of ABO-incompatible renal transplantations is excellent in Japan. However, previous reports have documented poor outcomes in patients with high (> 1:256) anti-A/B antibody titers pretreatment. The immunosuppressive protocol for ABO-incompatible high-titer renal transplantation has remained a medical challenge. METHODS: We treated 3 patients with high (> 1:512) anti-A/B antibody titers prior to ABO-incompatible renal transplantation. Our immunosuppressive protocol was initiated 1 month prior to surgery and included mycophenolate mofetil (1 g/d) and low-dose steroid (methylprednisolone [8 mg/d]). Two doses of the anti-CD20 antibody rituximab, (150 mg/m2) were administered 2 weeks before and on the day of transplantation. We performed antibody removal with 6 to 8 sessions of plasmapheresis (plasma exchange or double-filtration plasmapheresis) before transplantation. Splenectomy was also performed on the day of transplantation. Postoperative immunosuppression followed the same regimen as ABO-compatible cases, in which calcineurin inhibitors were initiated 3 days before transplantation combined with 2 doses of basiliximab. RESULT: With this protocol, the anti-A/B antibody was reduced to below 1:16 in all cases. All 3 patients underwent successful transplantation with a mean current serum creatinine of 1.32 mg/dL (range, 1.22-1.50 mg/dL). There were no episodes of antibody-mediated rejection. No serious complications or side effects were encountered. CONCLUSIONS: A preconditioning protocol consisting of rituximab infusions, splenectomy, plasmapheresis, and pharmacologic immunosuppression enabled ABO-incompatible renal transplantation in patients with high (> 1:512) anti-A/B antibody titer.

Experience of Lymphangiography as a Therapeutic Tool for Lymphatic Leakage After Kidney Transplantation.

INTRODUCTION: Lymphatic leakage after kidney transplantation is a relatively frequent complication but sometimes resistant to treatment, and there is no fixed treatment algorithm. The effectiveness of therapeutic lymphangiography for postoperative lymphatic or chyle leakage has been reported, but few reports are available regarding patients who have undergone kidney transplantation. In this study, we report our experience with lymphangiography as a therapeutic tool for lymphatic leakage after kidney transplantation. PATIENTS AND METHODS: Intranodal lymphangiography for lymphatic leakage was performed in 4 patients (3 male, 1 female; age range, 38 to 70 years old) after living kidney transplantation at the Osaka City University Hospital in Japan. The amount of drainage before lymphangiography was 169 to 361 mL/day. The procedure for intranodal lymphangiography was as follows: the inguinal lymph node was punctured under ultrasound guidance, and the tip of the needle was instilled at the junction between the cortex and the hilum, after which Lipiodol was slowly and manually injected. RESULTS: Lymphangiography was technically successful in 3 out of the 4 patients. In all successful cases, the amount of drainage decreased and leakage finally stopped without additional therapy such as sclerotherapy or fenestration. In 2 cases, we were able to directly detect the leakage site using lymphangiography. The time between lymphangiography and leakage resolution ranged from 8 to 13 days. There were neither complications of lymphangiography nor recurrence of lymphatic leakage in the successful cases. CONCLUSIONS: Intranodal lymphangiography may be not only a diagnostic tool but also an effective, minimally-invasive, and safe method for treatment of lymphatic leakage resistant to drainage after kidney transplantation.

First Report of a Rust Disease on Ohia Caused by Puccinia psidii in Hawaii.

Several species of Metrosideros (Myrtaceae), referred to as ohia in Hawaii, are endemic trees that comprise as much as 80% of the native Hawaiian forests. For centuries, these trees have provided niches for many indigenous and endangered plants and animals and are treasured by Hawaiians for their beauty and role in folklore and legends. During April 2005, a cultivated ohia plant was diagnosed by the Agricultural Diagnostic Service Center at the University of Hawaii at Manoa as infected by a rust fungus. Rust pustules containing abundant urediniospores were observed on leaves, stems, and sepals, causing discolored spots and severe deformity of young leaves and growing tips. By July 2005, a similar rust disease was observed on other plants in the family Myrtaceae; namely Syzygium jambos (L.) Alston, Eugenia koolauensis Degener, E. reinwardtiana (Blume) DC, and Psidium guajava L. Microscopic examination of the uredinia and urediniospores showed that the rust was morphologically similar to Puccinia psidii, which is reported as the guava or eucalyptus rust in Florida and Central and South America (1,2). To confirm the identity of this fungus, DNA was extracted from urediniospores of two isolates collected from ohia plants, and their nuclear ribosomal internal transcribed spacer (ITS) was amplified with two universal primers, ITS4 and ITS5 (3). Sequences of the ITS region of these isolates from ohia were identical to the P. psidii isolates provided by A. Alfenas in Brazil and M. Rayachhetry in Florida. Koch's postulate of the isolates, obtained from ohia, was performed using 1 × 108 spores/ml of urediniospores suspension in distilled water. The suspension was sprayed onto 6-month-old ohia seedlings. These inoculated seedlings were placed in clear plastic chambers maintained at 100% relative humidity and 22°C with a combination of 10-h fluorescent light period and a 14-h dark period. After 48 h of incubation, the seedlings were removed from the chambers and transferred to a greenhouse where the ambient temperature ranged from 20 to 24°C. Rust pustules appeared after 1 to 2 weeks of incubation. Symptoms first appeared as tiny, bright yellow, powdery eruptions that developed into circular, uredinial pustules on the stem and foliage. These pustules later expanded, coalesced, and became necrotic, spreading over the entire leaf and stem surfaces, and then leaves and stems were deformed and tip dieback ensued. These symptoms were the same as those observed on the naturally infected cultivated ohia plant mentioned above. P. psidii is reported to be native to South and Central America that later spread to some Myrtaceous plants in the Caribbean countries (1). It has a very wide host range within the family Myrtaceae (2). To our knowledge, this is the first report of P. psidii in Hawaii. This rust disease may pose a formidable threat to Myrtaceous species that make up the native Hawaiian forests and are grown as ornamental plants or for the production of wood chips. References: (1) T. A. Coutinho et al. Plant Dis. 82:819. 1998. (2) M. B. Rayachhetry et al. Biol. Control 22:38. 2001. (3) T. J. White et al. Page 315 in: PCR Protocols. M. A. Innis et al., eds. 1990.

Anesthetic management for cesarean section in moyamoya disease: a report of five consecutive cases and a mini-review.

We report five consecutive cases of neuraxial anesthesia for cesarean section in women with moyamoya disease. Either epidural or combined spinal-epidural anesthesia was provided, with adequate sedation using intravenous diazepam and/or opioid(s). Hemodynamic stability and normocapnia were well maintained, except in one patient who exhibited transient hypertension and hypocapnia due to anxiety. None of the parturients suffered from neurological deficit in the intra- or postoperative period, although one patient complained of numbness in her fingers at the end of surgery, but she was not hypotensive or hypocapneic. The neonates were all in good health. The literature is reviewed on the anesthetic management for cesarean section in patients with moyamoya disease.

Antitumor activity of 1 M tegafur-0.4 M 5-chloro-2,4-dihydroxypyridine-1 M potassium oxonate (S-1) against human colon carcinoma orthotopically implanted into nude rats.

The purpose of this study was to establish a nude rat orthotopic (organ-specific) human colorectal cancer model as an in vivo secondary screen for general evaluation of new anticancer agents against colorectal cancer and to evaluate practically the antitumor activity of 1 M tegafur-0.4 M 5-chloro-2,4-dihydroxypyridine-1 M potassium oxonate (S-1), a new p.o. fluoropyrimidine, in comparison to 1 M tegafur-4 M uracil [(UFT) effective on colorectal tumor in clinical]. After implantation of KM12C, a human colorectal cancer cell line, into the subserosal layer of the colon as a single-cell suspension, extensive local tumor growth and invasion to both the mucosal and the serosal sides were observed in all rats. Metastatic foci were also formed in both lymph nodes and lungs following local tumor growth in all of them. Using this method, an equitoxic dose of S-1 (15 mg/kg/day) and UFT (30 mg/kg/day) was administered p.o. for 14 consecutive days from 7 days after tumor cell implantation. S-1 showed a higher tumor growth inhibition than UFT did [S-1, 57% (significantly different from the tumor weight of the untreated group at P < 0.05) and UFT, 18% (P > 0.05)]. When both drugs were administered to nude rats bearing KM12C injected into the cecal wall for 28 consecutive days at equitoxic doses, the mean survival in the S-1 group was 16 days longer than that in the untreated group (P < 0.01) but that in the UFT group was only 8 days longer (P > 0.05). After the administration of an equitoxic dose of both drugs, S-1 gave the higher levels than UFT in various pharmacokinetic parameters as follows: area under the curve 0-24 h of 5-fluorouracil in plasma (3.5-fold), area under the curve 0-24 h of 5-fluorouracil incorporated into RNA in the tumor (1.3-fold), and thymidylate synthase inhibition rate (percentage) in the tumor (about 20%). Collectively, these findings suggested that this orthotopic human colorectal tumor model in nude rats is useful to evaluate the clinical therapeutic efficacy of drugs or therapies for colorectal cancer, and that S-1 had a higher therapeutic effect on human colorectal tumor than UFT did.

Clinical Experience of Late Conversion From Antimetabolites With Standard Exposure Calcineurin Inhibitors to Everolimus With Calcineurin Inhibitor Minimization in Stable Kidney Transplant Recipients With Good Renal Function.

INTRODUCTION: This study describes our clinical experience of late conversion from antimetabolites with standard exposure calcineurin inhibitors (CNIs) to everolimus with CNI minimization in stable kidney transplant recipients with good graft function. PATIENTS AND METHODS: A 1-year retrospective pilot study of 26 kidney recipients converted from antimetabolites with standard exposure CNIs to everolimus with CNI minimization was performed. The recipients enrolled in this study had normal or slightly impaired renal function defined as a serum creatinine value <2.0 mg/dL, and normal or slightly increased albuminuria defined as a urinary albumin excretion rate <100 mg/g creatinine. RESULTS: The median time from transplant to conversion was 39.5 months posttransplant (range, 3-275). Treatment with everolimus was stopped owing to adverse events in 11 patients (42.3%). In the analysis of the patients in whom everolimus was maintained, the mean estimated glomerular filtration rate (eGFR) significantly increased from 50.7 ± 11.9 mL/min/1.73 m(2) at baseline to 53.6 ± 13.9 mL/min/1.73 m(2) at 1 year after conversion. In the patients in whom everolimus was stopped during the observation period, there was no difference in eGFR between baseline and 1 year after conversion. CONCLUSIONS: This study demonstrated that, among the patients converted to everolimus at a late stage, there was no deterioration in renal function whether everolimus was maintained or stopped within 1 year after conversion.

Effects of Granulocyte and Monocyte Adsorptive Apheresis in Renal Transplantation Recipients With Concomitant Cytomegalovirus Infection.

BACKGROUND: Granulocyte and monocyte adsorptive apheresis (GMAA) is widely used as a treatment for active ulcerative colitis (UC) in Japan. Much attention has been paid to the possibility of GMAA for the treatment and control of cytomegalovirus (CMV) reactivation in patients with refractory UC and concomitant CMV infection. In this study, the effects of the combination of GMAA and antiviral therapy were examined in renal transplant recipients with concomitant CMV infection. METHODS: Combination therapy of GMAA and antiviral drugs was performed 9 times in 7 renal transplant recipients with concomitant CMV infection. Four of the cases were positive for CMV-IgG, and 3 were negative. The clinical presentation of CMV infection was viremia in 6 cases and disease (CMV retinitis) in 1 case. CMV infection was diagnosed by using an antigenemia assay (C7-HRP). GMAA session was performed once, and the duration of the session was 120 min. Immediately after the GMAA session, ganciclovir was administered at 5 mg/kg/body weight. CMV infection was monitored based on C7-HRP and CMV-DNA in the peripheral blood samples. RESULTS: All cases became negative for C7-HRP and CMV-DNA within 21 days (median, 14 days; range, 3-21 days) and 17 days (median, 6 days; range, 3-17 days), respectively, after starting the combination therapy. No side effects of GMAA were observed. CONCLUSIONS: This case series found that GMAA in combination with antiviral drugs may shorten the duration of treatment against CMV infection in renal transplant recipients. Further studies in a larger number of patients are required to confirm these results.

Macroamylasemia associated with ulcerative colitis.

We describe a very rare case in which macroamylasemia was associated with ulcerative colitis of total colitis type. The patient's serum amylase isozyme pattern by electrophoresis showed a broad abnormal peak toward the side of the positive pole compared with regular salivary and pancreatic fractions. Sephadex G-200 column chromatography showed a sedimentation coefficient of 6.6 S. Amylase activity was bound to IgG. Double diffusion experiments demonstrated that amylase activity could be precipitated in gel by an antibody to the lambda chain. Although inflammatory bowel disease is occasionally associated with hyperamylasemia due to pancreatitis, we emphasize that, when hyperamylasemia is recognized in patients with inflammatory bowel disease, macroamylasemia also should be considered.

Expression of peroxisome proliferator-activated receptor-gamma in renal ischemia-reperfusion injury.

The pathogenesis of ischemia-reperfusion injury is known to involve cytokines and particularly surface adhesion molecules, the expression of which initiates the attachment of inflammatory cells. Peroxisome proliferator-activated receptor (PPAR)-gamma is considered an important immunomodulatory factor as well as a fatty acid regulator. In this study, we researched the expression of PPAR-gamma in renal ischemia-reperfusion injury of the rat. The right kidney was harvested and left renal artery and vein were clamped under laparotomy. The kidney was reperfused after 90 minutes of ischemia, and rats were sacrificed at 0, 1.5, 3, 5, 12, and 24 hours after reperfusion. PPAR-gamma expression was analyzed by immunohistochemical staining using monoclonal antibody. In normal kidney, PPAR-gamma staining was weak on endothelial cells, including mesangial cells. On the other hand, PPAR-gamma staining was weak on interstitial cells and strong on collecting ducts of medulla. From 1.5 to 5 hours after reperfusion, PPAR-gamma staining was strong on endothelial cells, moderate on interstitial cells, and strong on collecting ducts. Twelve hours after reperfusion, PPAR-gamma staining was weak on endothelial cells, moderate on interstitial cells, and strong on collecting ducts. PPAR-gamma is induced on collecting ducts, interstitial cells, and endothelial cells in a rat model having renal ischemia-reperfusion injury.

Thymidylate synthase (TS) and ribonucleotide reductase (RNR) may be involved in acquired resistance to 5-fluorouracil (5-FU) in human cancer xenografts in vivo.

A human tumour sub-line resistant to 5-fluorouracil (5-FU) was established by once a day and every 5, with at least 50 administrations of 5-FU to KM12C human colorectal xenografts in nude mice. KM12C tumours treated with 5-FU showed less sensitivity to 5-FU with an inhibition rate (IR) of 7.9%, while non-treated tumours were highly sensitive to 5-FU with an IR of 81.8%. To clarify the mechanism of 5-FU-resistance, the activities of various enzymes and gene expressions involved in the metabolism of 5-FU in both parental and 5-FU-treated KM12C tumours were measured. A 2- to 3-fold increase in thymidylate synthase (TS) activity and 4- to 5-fold decrease in ribonucleotide reductase (RNR) activity were observed in 5-FU-resistant KM12C tumours, while the activities of orotate phosphoribosyltransferase (OPRT) thymidine and uridine phosphorylases (TP,UP) and thymidine kinase (TK) were not markedly changed as a consequence of repeated treatment of KM12C tumours with 5-FU. The expression of TS mRNA was also amplified in accordance with the increased TS activity in a 5-FU-treated tumour sub-line (KM12C/5-FU) compared with that in parental tumours, but changed expressions of both RNR-R1 and RNA-R2 mRNA could not be detected in the 5-FU-resistant tumour sub-line compared with the parental tumours, suggesting possible post-transcriptional regulation of RNR. Moreover, RNR, in addition to TS and OPRT, seemed to be related to the inherent insensitivity to 5-FU in human cancer xenografts. From these results, it may be concluded that RNR activity is one of the acquired or inherent resistant factors, including TS, to 5-FU in human cancer xenografts in vivo.

Prolongation of survival period and improvement of cancer cachexia by long-term administration of UFT.

We assayed the antitumoral and anticachectic activity of an oral fluoropyrimidine, UFT using the Colon-26-bearing murine cachexia model in terms of the survival period and parameters corresponding to clinical symptoms. Tumor growth was inhibited by UFT dose-dependently at the dose range of 12.5-25.0 mg/kg per day. Although UFT did not show significant growth inhibition at 15.0 and 12.5 mg/kg to which UFT gave little toxicity, the survival period was shown to be superior to the case of maximum tolerated dose (25.0 mg/kg per day). Next, we compared the maximum increase of life span (ILS) value for an administration schedule of continuous 9 days and 5 weeks which mimics the clinical schedule and found that the ILS value in the latter group was superior to the former and UFT improved cachexia, in the same manner. In the following experiments, we have clarified that UFT decreased the level of both plasma interleukin-6 (IL-6) and tumorous prostaglandin E2 (PGE2) and it highly accelerated IL-6 production from Colon-26. These findings suggest that UFT therapy, in low-toxic dose, could be useful to cachectic patients with poor performance status.

Enhancing 5-fluorouracil cytotoxicity by inhibiting dihydropyrimidine dehydrogenase activity with uracil in human tumor cells.

We analyzed dihydropyrimidine dehydrogenase (DPD) activity (radioenzymatic assay) and 5-fluorouracil (5-FU) cytotoxicity (MTT test) in the absence or presence of uracil in two human cancer cell lines, MIAPaCa-2 (pancreas tumor) and HuTu80 (duodenum tumor). Basal DPD activities in both were comparatively high; MIAPaCa-2, 101 and HuTu80, 153 pmol/min/mg protein, respectively. Twenty mu g/ml of uracil, a dose which did not influence cell proliferation, enhanced 5-FU cytotoxicity; MIAPaCa-2, 2.0-fold and HuTu80, 1.5-fold, respectively. Uracil inhibited both DPD activity and cell growth in a concentration-dependent manner, and exhibited maximum effect at molar ratios to 5-FU of more than 10 (DPD activity, almost complete inhibition; growth-inhibitory effect, about a 30% increase). In addition, the cytosolic DPD activity of OCC-1 human head and neck tumors, collected following the oral administration of ss mg/kg of uracil to tumor-bearing nude mice, decreased to about 50% of that of OCC-1 tumors not treated with uracil. These findings suggested that combined fluoropyrimidine and uracil treatment of tumors with high basal DPD, elicits a greater antitumor effect than fluoropyrimidines alone, since uracil could inhibit the degradation of 5-FU in the tumor. UFT, an oral fluoropyrimidine combined with uracil, is expected to be more effective in such tumors.

Preclinical antitumor efficacy of S-1: a new oral formulation of 5-fluorouracil on human tumor xenografts.

S-1 is a new oral formulation of 5-fluorouracil (5-FU) consisted of 1M tegafur, 0.4M 5-chloro-2,4-dihydroxypyridine that inhibits a degradation of 5-FU, and 1M potassium oxonate that regulates the phosphorylation of 5-FU in the gastrointestinal tract, and has shown excellent antitumor efficacy against various murine tumors in rodents, compared to the oral tegafur-based antitumor drug, UFT (1M tegafur plus 4M uracil), which is used clinically in Japan. To assess the possibility of clinically using S-1, we investigated the antitumor effect of S-1 on various human solid tumor xenografts in athymic rats and mice. In the nude rat system, S-1 was significantly effective against all 12 tumor xenografts tested when its minimum toxic dose (15 mg/kg) was administered for 14 days. Three tumors, stomach (H-81), colon (KM12C) and breast (H-31) markedly regressed in response to treatment with S-1 but not with UFT. The antitumor potency of S-1 was weak against human tumors xenografted into nude mice and likely similar to that of UFT. The reason of the discrepancy in the efficacy of S-1 between rats and mice was found to be that the 5-FU levels in the blood and tumor tissue of rats after oral administration of S-1 persisted much longer than in mice, and this prolonged maintenance of plasma 5-FU levels was significantly related to the potent antitumor activity of S-1. In conclusion, the results of this study suggested that based on its biological and pharmacokinetic characteristics, oral S-1 should be active against various human cancers.

The value of LYM-1 cells for examining vacuole formation and loss of cell viability induced by culture supernates of Helicobacter pylori.

Some strains of Helicobacter pylori are known to produce an extracellular cytotoxin that causes vacuolation in cultured mammalian cells. Screening for such strains makes use of HeLa cells which may not be sensitive enough to detect minimal changes. The aim of this study was to develop a more sensitive cell line. Vacuole formation was examined in HeLa cells, as well as four other cell lines established in this laboratory by ammonium chloride induction. Among five cell lines tested, LYM-1 cells were most sensitive for the detection of intracellular vacuolation with this agent. Loss of cell viability of LYM-1 and HeLa cells induced by H. pylori culture supernates was also examined: LYM-1 were more sensitive than HeLa cells. Cell death was not always accompanied by vacuole formation. This suggests that the mechanism whereby cell death occurs must be different from that for vacuole formation. LYM-1 cells may be useful when measuring vacuole formation and cell death of the cultured cells induced by culture supernates of clinical isolates of H. pylori.