The Impact of c-Fos/Activator Protein-1 Inhibition on Allogeneic Pancreatic Islet Transplantation.

Unpreventable allograft rejection is one of the main problems in pancreatic islet transplantation (PIT). Therefore, it is imperative to develop a more effective immunosuppressive strategy. The blockade of transcription factors has been a central part of T cell-depleting immunosuppressive therapies, as typified by the use of calcineurin inhibitors. The inhibition of activator protein-1 (AP-1) offers a novel strategy for immunosuppression in PIT, although to date, no reports on the effects of AP-1 inhibition are available. In this study, we investigated the immunosuppressive effects of T-5224, a c-Fos/AP-1-selective inhibitor, on murine T cells activated by αCD3+αCD28 mAbs. T-5224 inhibited proliferation, CD25 up-regulation, and the production of IL-2 and interferon-γ. In addition, T-5224 blocked the nuclear translocation of c-Fos/AP-1 in activated murine T cells. In BALB/c (H-2(d) )-to-C57BL/6J (H-2(b) ) mouse PIT, the 2-week administration of T-5224 prolonged survival of 600 islet allografts in a dose-dependent manner. When combined with a 2-week low-dose tacrolimus, the T-5224 treatment markedly prolonged allograft survival to over 300 days, while the efficacy was indeterminate when transplanted islet allograft mass was reduced to 300. We conclude that the c-Fos/AP-1 inhibition by T-5224 is a potentially attractive strategy for allogeneic PIT.

ASKP1240, a fully human anti-CD40 monoclonal antibody, prolongs pancreatic islet allograft survival in nonhuman primates.

A strategy for inhibiting CD40 has been considered as an alternative approach for immunosuppression because of undesirable effects of anti-CD154 monoclonal antibodies (mAbs). Previously, we demonstrated that ASKP1240, which is a fully human anti-CD40 mAb, significantly prolonged kidney and liver allograft survival in cynomolgus monkeys without causing thromboembolic complications. Herein, we evaluated the effect of ASKP1240 on pancreatic islet transplantation (PITx) in cynomolgus monkeys. Diabetes was induced by total pancreatectomy, and islet allografts were transplanted into the liver. Following PITx (8201-12 438 IEQ/kg), blood glucose levels normalized promptly in all animals. Control islet allografts were rejected within 9 days (n = 3), whereas ASKP1240 (10 mg/kg) given on postoperative days 0, 4, 7, 11 and 14 (induction treatment, n = 5) significantly prolonged graft survival time (GST) to >15, >23, 210, 250 and >608 days, respectively. When ASKP1240 (5 mg/kg) was administered weekly thereafter up to post-PITx 6 months (maintenance treatment, n = 4), GST was markedly prolonged to >96, >115, 523 and >607 days. During the ASKP1240 treatment period, both anti-donor cellular responses and development of anti-donor antibodies were abolished, and no serious adverse events were noted. ASKP1240 appears to be a promising candidate for immunosuppression in clinical PITx.

Luminal membrane expression of mesothelin is a prominent poor prognostic factor for gastric cancer.

BACKGROUND: Mesothelin is expressed in various types of malignant tumour, and we recently reported that expression of mesothelin was related to an unfavourable patient outcome in pancreatic ductal adenocarcinoma. In this study, we examined the clinicopathological significance of the mesothelin expression in gastric cancer, especially in terms of its association with the staining pattern. METHODS: Tissue specimens from 110 gastric cancer patients were immunohistochemically examined. The staining proportion and intensity of mesothelin expression in tumour cells were analysed, and the localisation of mesothelin was classified into luminal membrane and/or cytoplasmic expression. RESULTS: Mesothelin was positive in 49 cases, and the incidence of mesothelin expression was correlated with lymph-node metastasis. Furthermore, luminal membrane staining of mesothelin was identified in 16 cases, and the incidence of luminal membrane expression was also correlated with pT factor, pStage, lymphatic permeation, blood vessel permeation, recurrence, and poor patient outcome. Multivariate analysis showed that luminal membrane expression of mesothelin was an independent predictor of overall patient survival. CONCLUSION: We described that the luminal membrane expression of mesothelin was a reliable prognostic factor in gastric cancer, suggesting the functional significance of membrane-localised mesothelin in the aggressive behaviour of gastric cancer cells.

Intermittent pneumatic compression versus additional prophylaxis with enoxaparin for prevention of venous thromboembolism after laparoscopic surgery for gastric and colorectal malignancies: multicentre randomized clinical trial.

BACKGROUND: The role of antithrombotic chemoprophylaxis in prevention of venous thromboembolism (VTE) in laparoscopic surgery for gastric and colorectal malignancies is unknown. This study compared the addition of enoxaparin following intermittent pneumatic compression (IPC) with IPC alone in patients undergoing laparoscopic surgery for gastrointestinal malignancy. METHODS: In this multicentre RCT, eligible patients were older than 40 years and had a WHO performance status of 0 or 1. Exclusion criteria were prescription of antiplatelet or anticoagulant drugs and history of VTE. Patients were allocated to IPC or to ICP with enoxaparin in a 1 : 1 ratio. Stratification factors included sex, location of cancer, age 61 years and over, and institution. Enoxaparin was administered on days 1-7 after surgery. Primary outcome was VTE, evaluated by multidetector CT on day 7. RESULTS: Of 448 patients randomized, 208 in the IPC group and 182 in the IPC with enoxaparin group were evaluated. VTE occurred in ten patients (4·8 per cent) in the IPC group and six (3·3 per cent) in the IPC with enoxaparin group (P = 0·453). Proximal deep vein thrombosis and/or pulmonary embolism occurred in seven patients (3·4 per cent) in the IPC group and one patient (0·5 per cent) in the IPC with enoxaparin group (P = 0·050). All VTE events were asymptomatic and non-fatal. Bleeding occurred in 11 of 202 patients in the IPC with enoxaparin group, and one patient needed a transfusion. All bleeding events were managed by discontinuation of the drug. CONCLUSION: IPC with enoxaparin after laparoscopic surgery for gastric and colorectal malignancies did not reduce the rate of VTE. Registration number: UMIN000011667 ( https://www.umin.ac.jp/).

ANTECEDENTES: El papel de la quimioprofilaxis para la prevención del tromboembolismo venoso (venous thromboembolism, VTE) en la cirugía laparoscópica de los tumores malignos gástricos y colorrectales se desconoce. El objetivo de este estudio fue comparar la quimioprofilaxis antitrombótica (enoxaparina) y la compresión neumática intermitente (intermittent pneumatic compression, IPC) en pacientes sometidos a cirugía laparoscópica de tumores malignos abdominales. MÉTODOS: Se efectuó un ensayo aleatorizado, controlado y multicéntrico de pacientes sometidos a cirugía laparoscópica de tumores gástricos y colorrectales en Japón. Los criterios de inclusión eran pacientes mayores de 40 años de edad y con un estado funcional de WHO de 0-1. Los criterios de exclusión fueron la prescripción al paciente de fármacos antiagregantes o anticoagulantes y la historia de VTE. Los pacientes fueron asignados a IPC y ICP con la adición de enoxaparina en una relación 1:1. Los factores de estratificación incluyeron el sexo, la localización del cáncer, la edad mayor o menor de 61 años, y la institución. La enoxaparina fue administrada en los días postoperatorios (postoperative day, POD) 1-7. El resultado primario fue la VTE evaluada mediante tomografía computarizada multidetector en el POD7. Los cálculos de la potencia determinaron que se requerían 184 pacientes en cada grupo. RESULTADOS: De los 448 pacientes aleatorizados, se evaluaron finalmente 208 pacientes en el grupo IPC y 182 pacientes en el grupo IPC más enoxaparina. La VTE ocurrió en 10 de 208 pacientes en el grupo IPC (4,8%) y 6 de 182 pacientes en el grupo IPC más enoxaparina (3,3%) (P = 0,45). La trombosis venosa profunda proximal (proximal deep vein thrombosis, DVT) y/o el embolismo pulmonar (pulmonary embolism, PE) ocurrieron en 7 de 208 pacientes en el grupo IPC (3,4%) y 1 de 182 pacientes en el grupo IPC más enoxaparina (0,55%) (riesgo relativo 0,163, i.c. del 95% 0,020-1,314, P = 0,0503). Todos los eventos de VTE fueron asintomáticos y no mortales. Se produjo una hemorragia en 11 de 202 pacientes en el grupo IPC con enoxaparina (5,4%, i.c. del 95% 3,1%-9,5%, P < 0,001), y un paciente precisó transfusión. Todos los eventos hemorrágicos pudieron ser tratados con la interrupción del fármaco. CONCLUSIÓN: La IPC con la adición de enoxaparina tras cirugía laparoscópica de los tumores malignos gástricos y colorrectales no disminuye la VTE.

Transplantation of hepatocytes for prevention of intracranial hypertension in pigs with ischemic liver failure.

Intracranial hypertension leading to brain stem herniation is a major cause of death in fulminant hepatic failure (FHF). Mannitol, barbiturates, and hyperventilation have been used to treat brain swelling, but most patients are either refractory to medical management or cannot be treated because of concurrent medical problems or side effects. In this study, we examined whether allogeneic hepatocellular transplantation may prevent development of intracranial hypertension in pigs with experimentally induced liver failure. Of the two preparations tested--total hepatectomy (n = 47), and liver devascularization (n = 16)--only pigs with liver ischemia developed brain edema provided, however, that animals were maintained normothermic throughout the postoperative period. This model was then used in transplantation studies, in which six pigs received intrasplenic injection of allogeneic hepatocytes (2.5 x 10(9) cells/pig) and 3 days later acute liver failure was induced. In both models (anhepatic state, liver devascularization), pigs allowed to become hypothermic had significantly longer survival compared to those maintained normothermic. Normothermic pigs with liver ischemia had, at all time points studied, ICP greater than 20 mmHg. Pigs that received hepatocellular transplants had ICP below 15 mmHg until death; at the same time, cerebral perfusion pressure (CPP) in transplanted pigs was consistently higher than in controls (45 +/- 11 mmHg vs. 16 +/- 18 mmHg; p < 0.05). Spleens of transplanted pigs contained clusters of viable hepatocytes (hematoxylin-eosin, CAM 5.2). It was concluded that removal of the liver does not result in intracranial hypertension; hypothermia prolongs survival time in both anhepatic pigs and pigs with liver devascularization, and intrasplenic transplantation of allogeneic hepatocytes prevents development of intracranial hypertension in pigs with acute ischemic liver failure.

Dilation of the stump of the esophagus and intestine with Doyen's intestinal clamp followed by application of lidocaine facilitates the stapling anastomoses.

To avoid bowel tears on the esophagojejunal or colorectal mechanical anastomoses during insertion of the EEA stapler, we applied a local anesthetic to the stump of the bowel, then gently dilated the bowel with Doyen's intestinal clamp. This approach makes way for use of a larger cartridge and a more satisfactory anastomoses.

Direct introduction of a formamido group into the 7 alpha (6 alpha)-position of cephalosporins (penicillins).

A novel direct introduction of a formamido group into the 7 alpha (6 alpha)-position of cephalosporins (penicillins) was achieved by treatment of 7 beta (6 beta)-[(3,5-di-tert-butyl-4-oxo-2,5-cyclohexadien-1- ylidene)methylimino]cephem (penam) esters with N,N-bis(trimethylsilyl)formamide, followed by deblocking with Girard reagent T to give the corresponding 7 alpha (6 alpha)-formamido-7 beta (6 beta)-amino derivatives. Three 7 alpha-formamidocephalosporins were prepared by the conventional N-acylation of 7 alpha-formamidocephem. All of them were resistant to beta-lactamases, showing similar MIC values against both of a pair of a beta-lactamase-producing strain and the corresponding non or low-producing strain of the same species of bacteria, when tested on Staphylococcus aureus, Klebsiella pneumoniae, Escherichia coli, Proteus mirabilis, Proteus vulgaris, Morganella morganii, Enterobacter cloacae and Citrobacter freundii.

Cephalosporins. III. 7-(O-Aminomethylphenylacetamido)cephalosporanic acids with bicyclic heteroaromatics in the C-3 side chain.

Bicyclic heteroaromatic thiols with a bridge-head nitrogen atom were used for nucleophilic substitution of 7-ACA at the C-3 acetoxy function followed by N-acylation of the 7-amino group with o-aminomethylphenylacetic acid to afford a series of new cephalosporins (24) with potent antibacterial activity against gram-positive and gram-negative organisms. The most active member of this series was 7-(o-aminomethylphenylacetamido)-3-(tetrazolo-[4,5-b]pyridazin-6-ylthiomethyl)-3-cephem-4-carboxylic acid (BB-S 226) (24e) with antibacterial activity superior activity superior to cephalothin and cefazolin.

Improved synthesis of an ester-type prodrug, 1-acetoxyethyl 7-[(Z)-2-(2-aminothiazol-4-yl)-2-hydroxyiminoacetamido]-3-[(Z)-1- propenyl]-3-cephem-4-carboxylate (BMY-28271).

1-Acetoxyethyl 7-[(Z)-2-(2-aminothiazol-4-yl)-2-hydroxyiminoacetamido]-3- [(Z)-1-propenyl]-3-cephem-4-carboxylate (BMY-28271) is an ester-type prodrug of cephalosporin for oral use. Methods suitable for large scale preparation were investigated. The yield was improved by esterification of 7-[(Z)-2-(2-aminothiazol-4-yl)-2-trityloxyiminoacetamido]cep hem-4-carboxylic acid (11) followed by removal of the trityl group and, in addition, column chromatographic purification at each step was eliminated by optimization of the reaction conditions.

Synthesis and antifungal activities of alanine-exchanged analogs of pradimicin A.

A series of pradimicin analogs were designed and synthesized to investigate the effect of the amino acid side chain on the antifungal activity. The alanine-exchanged analogs (3a approximately 3q) were synthesized from 4'-N-Cbz-pradimic acid by coupling with appropriate amino acids or their equivalents followed by deblocking. All the D-alpha-amino acid derivatives except D-proline analog, 3k retained the antifungal activity.

Synthesis and structure-activity relationships of a new series of cephalosporins, BMY-28142 and related compounds.

The synthesis of a series of 7-[(Z)-2-(2-aminothiazol-4-yl)-2-oxyiminoacetamido] -3-ammoniomethyl-3-cephems is described. Variations of an oxyimino moiety in the 7-side chain and a quaternary ammonium moiety in the 3-side chain were examined and structure-activity relationships studied. BMY-28142, the 3-(N-methylpyrrolidinio)methyl derivative of the 7-alpha-methoxyimino series of cephalosporins, exhibited broad antimicrobial activity against both Gram-positive and Gram-negative bacteria including Pseudomonas aeruginosa.

Antifungal activities of pradimicin derivatives modified at C4'-amino group.

In order to explore potent derivatives of pradimicins (PRMs), modification of their C4'-amino group was carried out. 4'-N-Cyano (1,2), 4'-deamino-4'-nitroguanidino (4), 4'-deamino-4'-ureido (7-9) and 4'-deamino-4'-thioureido (10) derivatives were synthesized by trimethylsilylation of PRMs A and C, followed by condensation with appropriate reagents. 4'-Deamino-4'-guanidino (5) and 4'-deamino-4'-amidino (6) derivatives were synthesized by catalytic hydrogenation of 4 and 2, respectively. 4'-N-Nitroso derivative 3 was prepared by treatment of PRM A with nitrous acid. Among these compounds, the 4'-N-cyano derivative of PRM C (2) exhibited in vitro and in vivo antifungal activities comparable to the parent compounds together with good water-solubility.

Synthesis and antibacterial activity of cephalosporins having a catechol in the C3 side chain.

Cephalosporins having a catechol through a variety of linkages to the C3 position and a different C7 side chain were prepared. Among them, 3-(catechol-4- ylcarbonyloxy)methylcephalosporin (14) and 3-[(E)-3-(catechol-4-ylcarbonyloxy)-1-propen-1-yl]cephalospo rin (10) showed excellent activity against Gram-negative activity including ceftazidime-resistant Escherichia coli, Pseudomonas aeruginosa, Xanthomonas maltophilia and Pseudomonas cepacia.

Cephalosporins having a heterocyclic catechol in the C3 side chain. I. Enhancement of efficacy against gram-negative bacteria.

Two groups of cephalosporins substituted with a variety of heterocyclic catechols in the C3 side chain were synthesized. One is a group of 3-(heterocyclic catechol-substituted methyl)cephalosporins and another is 3-[(E)-3-heterocyclic catechol-substituted 1-propen-1-yl]cephalosporins. Cephalosporins in the latter group showed higher in vivo efficacies than those in the former group having the same heterocyclic catechol, especially against Pseudomonas aeruginosa A9843A, although there was no significant difference between their in vitro activity. Among the latter group, the 5,6-dihydroxybenzimidazole derivative (6e) and the 2,6-dihydro-7-hydroxy-6-oxo- isoquinoline derivative (6b) showed much higher activity than ceftazidime (CAZ) and imipenem (IPM) against P. aeruginosa A9843A both in in vitro and in vivo studies.

Cephalosporins having a heterocyclic catechol in the C3 side chain. II. Improvement of pharmacokinetic profile.

7-[(Z)-2-(2-Aminothiazol-4-yl)-2-methoxy-(or hydroxy)-iminoacetamido]-3- [propen-1-yl]-cephalosporins having a variety of heterocyclic catechol in 3-position of the propenyl group were synthesized. Among them, 6,7-dihydroxyisoquinoline derivatives, 2a and 2b, showed very high and prolonged blood levels after intramuscular administration to mice and higher in vivo antibacterial activity than expected from their in vitro activity. The former cephalosporin (2a) gave well-balanced in vitro and in vivo antibacterial spectra including anti-methicillin-resistant Staphylococcus aureus (MRSA) activity. The latter cephalosporin (2b) also showed good in vitro and in vivo activities against Gram-positive bacteria, especially against S. aureus A15036, a strain of MRSA, the in vivo activity being comparable to vancomycin but was lacking in anti-pseudomonal activity.

Synthesis and biological activity of a new cephalosporin, BMY-28232 and its prodrug-type esters for oral use.

The synthesis and structure-activity relationships of 7-[(Z)-2-(2-aminothiazol-4-yl)-2-hydroxyiminoacetamido]-3-[( Z)-1- propenyl]-3-cephem-4-carboxylic acid (BMY-28232), its 3-alkenyl analogs (6 and 7) and O-substituted derivatives of the oxyimino moiety (10) are described, as well as the oral pharmacokinetics and in vivo activities of the 1-acetoxyethyl ester of BMY-28232 (BMY-28271) and its analogous esters (11). The 3-alkenyl groups were introduced by the Wittig reaction of the ylide (2) prepared from the 3-chloromethyl cephem (1) to afford the Z (main) and E (minor) isomers regarding the 3-side chain. The O-substituted derivatives (10) were prepared by 7-N-acylation of the 7-amino cephem (4a) with the corresponding O-substituted side chain acids (8). The prodrug esters (11) were prepared by esterification of BMY-28232 with an appropriate halide. BMY-28232 was the most active among the 3-alkenyl analogs tested against Gram-negative organisms and much more active than the O-substituted derivatives against Gram-positive bacteria. BMY-28271 showed good oral bioavailability (66%) and good in vivo efficacy in mice against infections of Staphylococcus aureus Smith (PD50, 0.68 mg/kg) and Escherichia coli Juhl (0.54 mg/kg).

Synthesis and antifungal activities of pradimicin derivatives, modification at C4'-position.

The 4'-N-alkyl(1 approximately 10) and 4'-N-acyl derivatives (11 approximately 21) of pradimicins (PRMs) were synthesized by trimethylsilylation of PRMs A, C and FA-1 followed by condensation with appropriate alkylating and acylating agents. The 4'-hydroxy derivatives (23 and 24) were synthesized from PRM FA-2 in a 3-step sequence. Among these compounds, the 4'-N-carboxyl substituted alkyl (1, 5, 8 and 10), 4'-N-formyl (11) and 4'-axial-hydroxy (23) derivatives retained the antifungal activity of the parent compounds and showed great improvement in water solubility.

Synthesis and antifungal activity of pradimicin derivatives. Modifications on the aglycone part.

Synthesis and antifungal activity of pradimicin analogs modified on the aglycone part is described. Upon modification studies at various sites of the aglycone part using pradimicin A (PRM A), C-11 position was found to be the sole site to be modified without loosing antifungal activity. Further modification studies at C-11 position were carried out with 11-OH derivative of pradimicin T1 (PRM T1) because of its easy availability. Among the compounds prepared, 11-demethoxy derivative of PRM A (12) and 11-O-ethyl (13) and 11-O-fluoroethyl (14) derivatives of PRM T1 showed promising antifungal activity comparable to that of PRM A.

Synthesis of a new series of cephalosporins having 3-substituted-ammonio-1-propenyl group as the C-3 side chain.

The synthesis and antimicrobial activity of eight derivatives of 7-[(Z)-2-(2-aminothiazol-4-yl)- and 7-[(Z)-2-(5-amino-1,2,4-thiadiazol-3-yl)-2-methoxyiminoacetamido] cephalosporins having an (E) or (Z)-3-ammonio-1-propenyl group in the C-3 side chain are described. The (E)-propenyl derivatives were more active than their corresponding Z-isomers and showed well-balanced, broad antibacterial activity against both Gram-positive and Gram-negative bacteria including Pseudomonas aeruginosa.

Synthesis, stereochemistry, and biological properties of the depigmenting agents, melanostatin, feldamycin and analogs.

Syntheses of melanostatin and feldamycin have been completed from L-serine and L-threonine, respectively, and the configuration of unknown asymmetric carbons determined. Feldamycin analogs have also been prepared and the L-tryptophyl analog was the most potent in the depigmentation of Streptomyces bikiniensis and B16 melanoma cells.