Cosmetic outcome of implantation of cross-linked human acellular dermal matrix after parotidectomy.

Although skin depression after parotidectomy affects the patient's satisfaction with cosmesis we know of little research about it, so we attempted to alleviate it by inserting human acellular dermal matrix (hADM) after the operation. We made a retrospective analysis of the casenotes of 63 patients who were diagnosed with parotid tumours and were operated on between January 2015 and December 2016. Factors that affect satisfaction with cosmesis, including the use of hADM, sex, age, incision, size of tumour, sample size, complications, and the name of the surgeon were recorded and evaluated on a scale from 1 (most unsatisfactory) to 10 (very satisfactory), and the satisfaction according to each factor was compared. The mean (SD) follow-up period was 13 (6) months, and 19 of the 63 patients developed complications. Satisfaction was significantly better when hADM had been inserted (p=0.0008), when the patient was female (p=0.033), or there were no complications p=0.0161). On linear regression analysis, all three factors showed a significant causal relation with satisfactory cosmesis. Insertion of hADM after operations on the parotid gland seems to be effective in improving this by preventing skin depression.

[Clinical manifestations of three cases of surfactant protein C p. V39L mutation].

Objective: To investigate the clinical manifestations of surfactant protein C gene (SFTPC) exon-2 c. 115G>G/T (p.V39L). Method: Patients were screened for the entire coding sequence of SFTPC. Three cases from three children's hospital with mutation in p. V39L were reported. Result: All the three cases were females. The age of onset ranged from 2 months to 7 years. Two cases had recurrent lower respiratory tract infection and failed to thrive. One had chronic anoxia and clubbing fingers. Chest computed tomography (CT) showed diffused ground glass pattern, localized emphysema and intralobular septal thickening. In one case, early sign of cyst formation was also shown on CT. Two were lost to follow-up after alleviation of acute respiratory infection. One was treated with oral low-dose azithromycin and nebulized budesonide and terbutaline. She had recurrent lower respiratory tract infection in more than one year of follow-up. Conclusion: Mutations in SFTPC p. V39L cause interstitial lung diseases. Clinical manifestations included recurrent respiratory tract infections, chronic lung disease. Chest CT showing diffused ground glass pattern, localized emphysema, intralobular septal thickening and early sign of cyst formation. The treatment and prognosis need further study.

[Preparation of chaperone-antigen peptide vaccine derived from human gastric cancer stem cells and its immune function].

Objective: To explore the method of extracting chaperone antigen peptide complexes from gastric cancer stem cells and its immune function. Methods: Gastric cancer stem cells and gastric cancer cells were screened by low temperature ultrasonic lysis. After salting out and dialysis, the lysate supernatant was processed with SDS-PAGE to analyze the expression of chaperone antigen peptide complexes, and then was separated and purified with CNBr-activated SepharoseTM 4B. Reverse high pressure liquid chromatography (HPLC), SDS-PAGE and Western blotting were used to analyze the purity and nature of the acquired albumen. Lymphocyte proliferation assay and lymphocytotoxicity assay were used to ditermine the immunological activity of the chaperone-antigen peptide complexes. Results: The chaperone antigen peptide complexes of gastric cancer stem cells were prepared and identified successfully, of which the main components were the antigen peptides of HSP60, HSP70, HSP90 and HSP110. 0.75 µg and 1.00 µg HSP70-antigen peptide and 1.00 µg HSP90-antigen peptide activated lymphocytes significantly. Their A(490) values were 0.26±0.03, 0.45±0.05 and 0.32±0.04, respectively, while the corresponding doses of HSP60-antigen peptide and HSP110-antigen peptide did not activate lymphocytes. The killing rates of 1.00 µg HSP70-antigen peptide and 1.00 µg HSP70 were (45.0±2.0)% and (16.0±2.0)%, respectively, showing a significant difference (P=0.012). Similarly, the killing rates of 1.00 µg HSP90-antigen peptide and 1.00 µg HSP90 were (36.0±5.0)% and (13.0±4.0)%, respectively, also showing a significant difference (P=0.048). Conclusions: The amount of chaperone antigen peptide complexes in gastric cancer cells is extremely low, but it is obviously increased in gastric cancer stem cells. After purification, the chaperone antigen peptide complexes with high purity can be prepared. The extracted chaperone antigen peptide complexes have stronger immunogenicity, and can be used to make tumor vaccine in vitro, which may have a good application value in the targeted therapy of gastric cancer.

Reversal of cisplatin resistance in non-small cell lung cancer stem cells by Taxus chinensis var.

Drug resistance in cells is a major impedance to successful treatment of lung cancer. Taxus chinensis var. inhibits the growth of tumor cells and promotes the synthesis of interleukins 1 and 2 and tumor necrosis factor, enhancing immune function. In this study, T. chinensis var.-induced cell death was analyzed in lung cancer cells (H460) enriched for stem cell growth in a defined serum-free medium. Taxus-treated stem cells were also analyzed for Rhodamine 123 (Rh-123) expression by flow cytometry, and used as a standard functional indicator of MDR. The molecular basis of T. chinensis var.-mediated drug resistance was established by real-time PCR analysis of ABCC1, ABCB1, and lung resistance-related protein (LRP) mRNA, and western blot analysis of MRP1, MDR1, and LRP. Our results revealed that stem cells treated with higher doses of T. chinensis var. showed significantly lower growth inhibition rates than did H460 cells (P < 0.05). The growth of stem and H460 cells treated with a combination of T. chinensis var. and cisplatin was also significantly inhibited (P < 0.05). Rh-123 was significantly accumulated in the intracellular region and showed delayed efflux in stem cells treated with T. chinensis var. (P < 0.05), compared to those treated with verapamil. T. chinensis var.-treated stem cells showed significant downregulation of the ABCC1, ABCB1, and LRP mRNA and MRP1, MDR1, and LRP (P < 0.05) compared to H460 cells. Thus, T. chinensis var.-mediated downregulation of MRP1, MDR1, and LRP might contribute to the reversal of drug resistance in non-small cell lung cancer stem cells.

Association of gene polymorphisms with the risk of warfarin bleeding complications at therapeutic INR in patients with mechanical cardiac valves.

WHAT IS KNOWN AND OBJECTIVE: Pharmacogenetic studies of the genetic regulation of warfarin dose requirement have been reported, but few have been on the bleeding complications at therapeutic international normalized ratio (INR). This study aimed to evaluate the effect of gene polymorphisms of CYP2C9, VKORC1, thrombomodulin (THBD) and C-reactive protein (CRP) on the risk of bleeding complications of warfarin at therapeutic INR in Korean patients with mechanical cardiac valves. METHODS: A retrospective warfarin pharmacogenetic association study was performed. One hundred and forty-two patients with mechanical cardiac valves who were on warfarin anticoagulation therapy and maintained INR levels of 2·0-3·0 for 3 consecutive time intervals were followed up. CYP2C9 rs1057910, VKORC1 rs9934438, CRP rs1205, THBD rs1042580 and THBD rs3176123 were genotyped. The association between genotypes and warfarin bleeding complications was evaluated using logistic regression analysis, adjusted for demographic and clinical factors. RESULTS AND DISCUSSION: Of 142 eligible patients, 21 patients (14·8%) had bleeding complications at therapeutic INR. Patients with the G allele in THBD rs1042580 (AG or GG) had a lower risk of bleeding than patients with the AA genotype (adjusted OR: 0·210, 95% CI: 0·050-0·875, P = 0·032). The THBD rs3176123 polymorphism did not show any association with bleeding. For CRP rs1205, patients with the A allele (GA or AA genotype) had a higher risk of bleeding than patients with the GG genotype (adjusted OR: 5·575, 95% CI: 1·409-22·058, P = 0·014). Variant VKORC1 and CYP2C9 genotypes did not confer a significant increase in the risk for bleeding complications. WHAT IS NEW AND CONCLUSIONS: As expected, no association could be found between bleeding complications and two dose-related genes (CYP2C9*3 and VKORC1 rs9934438). In contrast, our results suggest that two genetic markers (THBD rs1042580 and CRP rs1205) could be predictors of bleeding complications of warfarin at normal INR. Given the retrospective study design and the relatively small sample size, our hypothesis requires further independent validation using more robust prospective designs. However, additional retrospective studies similar to ours but in populations with different genetic backgrounds should also be useful.

Treadmill exercise improves cognitive function and facilitates nerve growth factor signaling by activating mitogen-activated protein kinase/extracellular signal-regulated kinase1/2 in the streptozotocin-induced diabetic rat hippocampus.

This study aimed to investigate the effects of regular treadmill exercise on nerve growth factor (NGF) expression, the improvement of cognitive function in the hippocampus of diabetic rats, and to understand the molecular mechanisms through which the relevant signaling factors act. We investigated the effects of regular treadmill exercise for 6 weeks on NGF, tyrosine kinase receptor A (TrkA), p75 receptor, phosphatidylinositol 3-kinase (PI3-K), mitogen-activated protein kinase (MAPK)/extracellular signal-regulated kinase 1/2 (Erk1/2), cyclic AMP response element-binding protein (CREB), and caspase-3 protein levels; we also assessed cell survival and cognitive function. Forty male Sprague-Dawley rats were divided into four groups: (1) normal control group (NCG: n=10); (2) normal exercise group (NEG: n=10); (3) diabetes control group (DCG: n=10), and (4) diabetes exercise group (DEG: n=10). Diabetes was induced by injecting streptozotocin (STZ; 55 mg/kg dissolved in 0.05 M citrate buffer, pH 4.5, i.p.) into rats. Rats were subjected to treadmill exercise for 5 days a week over 6 weeks, and the speed of the treadmill was gradually increased. In a passive avoidance test, the retention latency in the DCG was significantly shorter than that in the DEG (P<0.05). Increased 5-bromo-2'-deoxyuridine-5'-mono-phosphate (BrdU)-labeled cells (P<0.001) and significant increases in NGF and TrkA protein levels were observed in the hippocampal dentate gyrus in the NEG and DEG (P<0.001 and P<0.01, respectively). The p75 receptor protein level significantly increased in the NEG but decreased in the DCG (P<0.001). The p-PI3-K and t-CREB protein levels significantly increased in the NEG (P<0.001 and P<0.05, respectively), whereas t-Erk1/2 significantly decreased in the DCG (P<0.01, P<0.01, respectively). p-Erk1/2 and p-CREB protein levels significantly increased in the NEG and DEG (P<0.001, P<0.001, and P<0.01, respectively). Caspase-3 protein levels significantly increased in the DCG (P<0.001). These results show that treadmill exercise improves cognitive function, increases the number of BrdU-labeled cells, and increases NGF levels, by the activation of the MAPK/Erk1/2 signaling pathway in the hippocampus of diabetic rats.

Celecoxib induces hepatic stellate cell apoptosis through inhibition of Akt activation and suppresses hepatic fibrosis in rats.

BACKGROUND AND AIMS: Activated hepatic stellate cells (HSCs) but not quiescent HSCs express cyclo-oxygenase-2 (COX-2), suggesting that the COX-2/prostanoid pathway has an active role in hepatic fibrogenesis. However, the role of COX-2 inhibitors in hepatic fibrogenesis remains controversial. The aim of this study was to investigate the antifibrotic effects of celecoxib, a selective COX-2 inhibitor. METHODS: The effects of various COX inhibitors-that is, ibuprofen, celecoxib, NS-398 and DFU, were investigated in activated human HSCs. Then, the antifibrotic effect of celecoxib was evaluated in hepatic fibrosis developed by bile duct ligation (BDL) or peritoneal thioacetamide (TAA) injection in rats. RESULTS: Celecoxib, NS-398 and DFU inhibited platelet-derived growth facor (PDGF)-induced HSC proliferation; however, only celecoxib (> or =50 microM) induced HSC apoptosis. All COX inhibitors completely inhibited prostaglandin E(2) (PGE(2)) and PGI(2) production in HSCs. Separately, PGE(2) and PGI(2) induced cell proliferation and extracellular signal-regulated kinase (ERK) activation in HSCs. All COX inhibitors attenuated ERK activation, but only celecoxib significantly inhibited Akt activation in HSCs. Celecoxib-induced apoptosis was significantly attenuated in HSCs infected with adenovirus containing a constitutive active form of Akt (Ad5myrAkt). Celecoxib had no significant effect on PPARgamma (peroxisome proliferator-activated receptor gamma) expression in HSCs. Celecoxib inhibited type I collagen mRNA and protein production in HSCs. Oral administration of celecoxib (20 mg/kg/day) significantly decreased hepatic collagen deposition and alpha-SMA (alpha-smooth muscle actin) expression in BDL- and TAA-treated rats. Celecoxib treatment significantly decreased mRNA expression of COX-2, alpha-SMA, transforming growth factor beta1 (TGFbeta1) and collagen alpha1(I) in both models. CONCLUSIONS: Celecoxib shows a proapoptotic effect on HSCs through Akt inactivation and shows antifibrogenic effects in BDL- and TAA-treated rats, suggesting celecoxib as a novel antifibrotic agent of hepatic fibrosis.

Wildfire of Soybean Caused by Pseudomonas syringae pv. tabaci, a New Disease in Korea.

In 2006 and 2007, a new bacterial disease was observed in field-cultivated soybeans in Boeun District and Munkyung City of Korea. The disease caused severe blighting of soybean (Glycine max) leaves. Soybean leaves in fields showed yellowish spots with brown centers. Brown and dead areas of variable size and shape were surrounded by wide, yellow haloes with distinct margins. Spots might coalesce and affected leaves fell readily. Seven bacterial strains were isolated from chlorotic areas of soybean leaves and all produced white colonies on trypticase soy agar. With the Biolog Microbial Identification System, version 4.2, (Biolog Inc., Hayward, CA) all strains and Pseudomonas syringae pv. tabaci CFBP2106T were identified as P. syringae pv. tabaci with a Biolog similarity index of 0.28 to 0.52 and 0.48 after 24 h. Pathogenicity of the strains (three plants per strain) on soybean leaves at the V5 stage (cv. Hwanggeum) was confirmed by rub inoculation with bacterial suspensions (1 × 108 CFU/ml) in sterile distilled water on the lesions cut 1 cm long on the upper side of the leaves with razor blades and by pinprick on 3-week-old leaves of tobacco (Nicotiana tabacum cv. Samsun) in the greenhouse. Wildfire symptoms on the soybean leaves and faint halos on tobacco leaves were observed 4 days after inoculation. The identification of reisolated bacterial strains was confirmed with the metabolic fingerprintings on Biolog. LOPAT tests (1) and phenotypic characteristics (3) of the strains were similar to those of the CFBP2106T. Colonies were levan positive, oxidase negative, potato soft rot negative, arginine dihydrase negative, and tobacco hypersensitivity negative. All strains were gram-negative, aerobic rods with a polar flagellum. Strains were negative for esculin hydrolysis, gelatin liquefaction, urea production, accumulation of poly-ß-hydroxy butyrate, starch hydrolysis, ornithine dihydrolase, lysine dihydrolase, growth at 37°C, utilization of geraniol, benzoate, cellobiose, sorbitol, trehalose, l-rhamnose, and adonitol. Positive reactions were catalase and arbutin hydrolysis, utilization of sorbitol, d-arabinose, and dl-serine. The strains were variable in utilization of mannitol, sucrose, and d-arabinose. The 1,472-bp PCR fragments of strains, BC2366 (GenBank Accession No. FJ755788) and BC2367 (No. FJ755789) was sequenced using 16S rDNA universal primers (2). The sequences shared 100% identity with the analogous sequences of P. syringae pv. glycenea (GenBank Accession No. AB001443) available in NCBI databases. Based on the phenotypic, genetic, and pathological characteristics, all strains were identified as P. syringae pv. tabaci. To our knowledge, this is the first report of P. syringae pv. tabaci causing wildfire on soybean in Korea. References: (1) R. A. Lelliott et al. J. Appl. Bacteriol. 29:470, 1966. (2) I.-S. Myung et al. Plant Dis. 92:1472, 2008. (3) N. W. Schaad et al., eds. Laboratory Guide for Identification of Plant Pathogenic Bacteria. 3rd ed. The American Phytopathological Society, St. Paul, MN, 2001.

Asp-Tyr-Leu-Lys tetrapeptide inhibits airway inflammation in toluene-2,4-diisocyanate-induced asthma mice.

BACKGROUND: Airway inflammation and remodelling contribute to chronic airway obstruction of asthma. Currently, no medication effectively controls airway remodelling and related vascular changes. Therefore, new strategies need to be developed. The kringle 5 domain has anti-angiogenic activity resulting from the tetrapeptide Lys-Leu-Tyr-Asp (KLYD). OBJECTIVE: To investigate the therapeutic effect of KLYD and its inverse form Asp-Tyr-Leu-Lys (DYLK) on the inflammation and remodelling of toluene-2,4-diisocyanate (TDI)-sensitization/challenged mice. METHODS: Cell numbers were measured in the presence of various concentrations of KLYD and DYLK using in vitro endothelial cell proliferation assay. The changes of cell number and the level of vascular endothelial growth factor (VEGF) in bronchoalveolar lavage (BAL) fluid and response to methacholine (MCh) were measured using the in vivo TDI-sensitized/challenged mice model. Muc5ac, smooth muscle actin (SMA) and proliferating cell nuclear antigen (PCNA) protein expression was analysed on trachea and intrapulmonary bronchi using immunohistochemical stain. RESULTS: Compared with KLYD, DYLK had a greater inhibitory effect on endothelial cell proliferation (P<0.05). Pre-treatment of DYLK showed dose-dependent reduction in the response to MCh (P<0.05) and numbers of inflammatory cells in BAL fluids of TDI-sensitized/challenged mice. TDI induced increases in Muc5ac, SMA and PCNA protein expression and VEGF levels, which were also abolished by DYLK treatment. CONCLUSIONS: Local administration of DYLK effectively inhibits the airway inflammation and airway remodelling of TDI-sensitized/challenged mice via down-regulation of VEGF. These findings suggest that anti-angiogenic peptide therapies, such as local administration of DYLK, are an effective strategy for the treatment of remodelling in asthma.

Characterization of Helicoverpa armigera nucleopolyhedrovirus orf33 that encodes a novel budded virion derived protein, BV-e31.

Homologues of Helicoverpa armigera nucleopolyhedrovirus (HearSNPV) orf33 are found in all 22 completely sequenced members of the lepidopteran nucleopolyhedroviruses and granuloviruses, but so far their functions are unknown. In this report, we describe the characterization of HearSNPV orf33 (ha33). Northern blot analysis showed a single transcript of ha33 of approximately 0.7 kb was transcribed beginning at 3 h post-infection in infected Helicoverpa zea cells (HzAM1) and the gene product could be detected as early as 6 h post-infection by western blot analysis using a rabbit derived polyclonal antibody, suggesting it was an early gene. Western blot analysis also demonstrated the ha33 protein in infected cells was a 31 kDa protein, larger than the theoretical size of 28.4 kDa, and located in the envelope fraction of budded virions (BVs). The results suggested that HearSNPV ha33 gene is a functional gene that encodes a novel structural protein of baculovirus BVs, BV-e31.

Construction of recombinant swinepox viruses and expression of the classical swine fever virus E2 protein.

To explore the swinepox virus (SPV) as a potential live vector for immunization, a vector was developed for the construction of a recombinant SPV carrying foreign genes. In this system, a foreign gene placed under the strong vaccinia virus promoter P(11) can be inserted into the viral thymidine kinase (TK) gene, and the recombinant virus can be isolated in a non-selective medium by the co-expression of E. coli lacZ gene. Compared with the wild type virus, the TK(-)recombinant SPV showed a modest level of attenuation in porcine cells while more attenuation was observed in monkey or human cells. Using this system, a recombinant virus expressing the E2 glycoprotein of classical swine fever virus (CSFV) was produced. Engineered with the gX signal sequence of the pseudorabies virus, and transmembrane domain of E2, the E2 protein was expressed as a dimeric form in the cytoplasm of the infected cells.

High-level expression of canine parvovirus VP2 using Bombyx mori nucleopolyhedrovirus vector.

For the potential use as recombinant vaccine, canine parvovirus (CPV) major capsid protein VP2 was expressed using Bombyx mori nucleopolyhedrovirus (BmNPV) vector. CPV VP2 gene was introduced into polyhedrin-based BmNPV transfer vector pBmKSK3, and recombinant virus BmK1-Parvo was prepared. When anti-CPV.VP2 monoclonal antibody was employed in immunofluorescence staining, an intense signal was observed within BmK1-Parvo-infected Bm5 cells but not within uninfected cells or cells infected with a wild-type BmNPV-K1. In hemagglutination assay, the expression level of VP2 were 3.2 x 10(3) HA units/ml from infected Bm5 cells, 2.1x 10(5) HA units/larvae from infected larval fat body, and 1.6x 10(6) HA units/ml from infected larval hemolymph. These results suggested that BmNPV vector system using B. mori larva as host could be applied to efficient mass-production of recombinant vaccines.

Expression of envelope protein (E2) of bovine viral diarrhea virus in insect cells.

The gene encoding the envelope glycoprotein (E2) of bovine viral diarrhea virus (BVDV) was expressed in a baculovirus. The expressed protein was detected on the surface of infected cells by immunofluorescence. Western blotting analysis showed the presence of the expressed protein of a similar molecular size to the E2 protein. The antigenicity of expressed protein were tested in guinea pigs and cattle. The immunized animals developed neutralizing antibodies against BVDV.

Synthesis and antitumor activity of 1-beta-D-arabinofuranosylcytosine conjugates of optical isomers of ether and thioether lipids.

Four 1-beta-D-arabinofuranosylcytosine conjugates (ara-C) (1a, b and 2a, b) of sn-1 and sn-3 isomers of 1-O-octadecyl-2-O-palmitoylglycerol and its 1-S-alkyl analogue have been synthesized, and their antitumor activity against L1210 lymphoid leukemia in mice were compared with those of the previous conjugates (3a, b) of racemates in order to determine the significance of chirality of the glycerol moieties for activity. Administration (i.p.) of a single dose (300 mg/kg) of conjugates of sn-1 (1a), sn-3 (2a) and rac (3a) isomers of the ether lipid increased lifespan of i.p. implanted L1210 lymphoid leukemic DBA/2J mice by 169, 175 and 236%, respectively. The sn-1 (1b), sn-3 (2b), and rac (3b) isomers of the thioether lipid with a single dose of 300 mg/kg produced an increase in lifespan values of 238, 263 and 250%, respectively. The results indicate that chirality of the glycerol moieties appears not to be critical for the activity, and racemates 3a and 3b are promising prodrugs of ara-C for further clinical investigations.

2'-Fluorinated isonucleosides. 1. Synthesis and biological activity of some methyl 2'-deoxy-2'-fluoro-2'-pyrimidinyl-D-arabinopyranosides.

New reactions of methyl 2,2-difluoro glycosides are described that were utilized for synthesis of some novel nucleoside derivatives. Thus, treatment of methyl 2-deoxy-2,2-difluoro-3,4-O-isopropylidene-alpha (beta)-D-erythro-pyranoside (2) with anhydrous HCl resulted in selective displacement of one fluorine atom with chlorine to give a 2-deoxy-2-chloro-2-fluoro glycoside 3. Reaction of 3 with silylated uracil in the presence of SnCl4 provided a 2-deoxy-2-fluoro-2-uracil-substituted glycoside 4. 2-Fluoro-2-deoxy glycosides substituted with other pyrimidines at C-2 were prepared similarly by the reaction of acylated 2,2-difluoro or 2-fluoro-2-bromo derivatives (5 and 6, respectively) with silylated pyrimidines. The resulting 2'-fluorinated isonucleosides were evaluated for their antitumor and antiviral activities. Compounds 7a,b, 8a,b, and 10a,b demonstrated 50% tumor cell growth inhibition in vitro (IC50) at 10(-4)-10(-5) M. At similar concentrations no antiviral activity was observed in vitro. Therapeutic activity was obtained with 7a,b and 8a,b in DBA/2 mice with L1210 leukemia. Administration of 7a,b at 500 mg/kg, ip daily, for 5 consecutive days, resulted in a 55% increase in life span (% ILS) while administration of 8a,b in the same manner at 200 mg/kg caused a 29% ILS. Treatment with 7a,b to mice with drug-resistant L1210 sublines (5-FU and araC) resulted in 22 and 57% increases in life span, respectively. Lewis lung carcinoma and M5076 sarcoma in mice also responded to the administration of 7a,b with reductions in tumor growth for both tumors and significant increases in life span in mice with Lewis lung carcinoma. Although the mechanism of action of 7a,b is not known, it has been found to be a relatively fast-acting, cell-cycle nonspecific cytotoxic agent that decreases [3H]deoxyuridine incorporation, blocks L1210 cells at the G2 phase of the cell cycle, and is not reversed by exogenous thymidine. These 2'-fluorinated isonucleosides have demonstrated biological activity and may have potential as antitumor drugs.

Nucleoside conjugates. 10. Synthesis and antitumor activity of 1-beta-D-arabinofuranosylcytosine 5'-diphosphate-1,2-dipalmitins.

Three 1-beta-D-arabinofuranosylcytosine 5'-diphosphate-1,2-dipalmitins from L-, D-, and DL-alpha-dipalmitoylphosphatidic acids have been synthesized and their antitumor activity against two ara-C2 resistant L1210 lymphoid leukemia sublines in mice were evaluated. These new prodrugs of ara-C include ara-CDP-L-dipalmitin, ara-CDP-D-dipalmitin, and ara-CDP-DL-dipalmitin. The L and DL isomers produced significant increase in life span (greater than 400%) and four to five long-term survivors (greater than 45 days) out of six animals bearing ip implanted partially ara-C resistant L1210 subline [L1210/ara-C (I)], while the D isomer displayed a marginal activity (ILS 100-121%). In contrast, the L isomer was completely ineffective against deoxycytidine kinase deficient ara-C resistant L1210 subline [L1210/ara-C (II)]. However, the results demonstrate that the L and DL isomers of ara-CDP-dipalmitin are promising new prodrugs of ara-C with improved efficacy.

Nucleoside conjugates. 7. Synthesis and antitumor activity of 1-beta-D-arabinofuranosylcytosine conjugates of ether lipids.

Three new 1-beta-D-arabinofuranosylcytosine conjugates of ether lipids (alkyl glycerols) linked by a pyrophosphate diester bond have been prepared and evaluated against mouse leukemia L1210 and P388. These include ara-CDP-rac-1-O-hexadecyl-2-O-palmitoylglycerol (9a) (ara-CDP = 1-beta-D-arabinofuranosylcytosine 5'-diphosphate), ara-CDP-rac-1-O-octadecyl-2-O-palmitoylglycerol (9b), and ara-CDP-rac-1-O-octadecyl-2-O-methylglycerol (9c). Among them, conjugate 9a produced significant increase in life span (200-293%) in mice bearing ip and ic implanted L1210 lymphoic leukemia at a total dose of 400-500 mg (406-508 mumol/kg). Significant schedule dependence was not observed when the conjugate was given ip once daily on day 1, days 1, 5, and 9, and days 1-5. The new conjugates are water soluble by sonication.

Nucleoside conjugates. 8. The preparation of 5-fluoro-2'-deoxyuridine conjugates of corticosteroids.

Three 5'-(steroid-21-phosphoryl)-5-fluoro-2'-deoxyuridines (VI-VIII) have been prepared and characterized by uv, ir, 1H-nmr, elemental analysis, chemical and enzymatic hydrolyses. These new compounds are 5-fluoro-2'-deoxyuridine conjugates of cortisol (VI), cortico-sterone (VII), and prednisolone (VIII). Besides the physical and analytical data, all of the conjugates were demonstrated to be enzymatically hydrolyzed to the corresponding steroid and 5-fluoro-2'-deoxyuridine 5'-monophosphate (III), and the latter was further shown to be hydrolyzed to 5-fluoro-2'-deoxyuridine (II) by phosphodiesterase I, 5'-nucleotidase, and acid phosphatase. However, they were shown to be resistant to hydrolysis by bacterial alkaline phosphatase.

Synthesis of N,N'-disubstituted N''-2-(2-quinolinylmethylthio)ethylguanidines as potential anticancer agents.

A simple method for obtaining the title compounds was found in the alkaline rearrangement of S-2-aminoethylisothiouronium salts, which were obtained from the condensation of thiourea or substituted thioureas with 2-bromoethylamine hydrobromide. No activity was found for the substituted guanidines against P388 lymphocytic leukemia in mice, or as H2-receptor antagonists.