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2.
J Pediatr Urol ; 13(4): 357.e1-357.e7, 2017 Aug.
Article in English | MEDLINE | ID: mdl-28865885

ABSTRACT

INTRODUCTION: Hypercalciuria, hypocitraturia and cystinuria are the most common underlying metabolic stone abnormalities in children. The present study compared stone growth patterns, stone burden, and the risk of stone-related surgery among these underlying metabolic conditions. METHODS: A retrospective cohort of 356 children with renal stones, followed from 2000 to 2015, was studied. Differences among metabolic groups were determined using Kruskal-Wallis test; the Scheffé-test was used for multiple comparisons to determine differences among single groups. Independent sample t-test was used when adequate, given the sample size, and Chi-squared test was used for categorical variables. Stone growth rates were calculated as differences in diameter divided by time elapsed between U/Ss (mm/year). Logistic regression was performed to assess the effect of initial stone size on the likelihood of surgery. RESULTS: Median stone size at presentation was significantly different among groups, with cystinuria being the group with the largest proportion of stones >10 mm, while patients with stones <5 mm were likely to have a normal metabolic workup (P < 0.05). Stones with a higher growth rate were found in the operative group, while slower growing stones were mostly managed conservatively (3.4 mm/year vs 0.8 mm/year, respectively; P = 0.014). However, stone growth rates were not significantly different among metabolic groups. On the other hand, the rate of new stone formation in cystinuric patients at their first follow-up was 30.4%, which was significantly higher than in patients with hypercalciuria (16.3%) or with a normal metabolic workup (17.2%; P < 0.05). Compared with stones <5 mm, stones measuring 5-10 mm were more than four times more likely to result in surgery, whereas the likelihood of surgery for 10-20 mm or >20 mm stones was almost 16 or 34 times, respectively (P < 0.001). CONCLUSIONS: It is believed that this is the first study to evaluate stone growth patterns, stone burden and surgical risk among children with hypercalciuria, hypocitraturia and cystinuria. Cystinuric patients presented with larger stones at the time of diagnosis, higher new stone formation rates, and were at higher risk of surgery. While no significant difference of growth rate was found among metabolic groups, stones with a higher growth rate were significantly more likely to result in surgical treatment than slower growing stones. Initial stone size, location of largest stone, previous urinary tract infection, and patient's metabolic type significantly influenced the likelihood of a surgical intervention. Better understanding of the natural history ultimately helps surgeons and clinicians defining prognosis, treatment, and prevention plans for pediatric urolithiasis.


Subject(s)
Cystinuria/complications , Hypercalciuria/complications , Kidney Calculi/pathology , Kidney Calculi/surgery , Urolithiasis/pathology , Urolithiasis/surgery , Adolescent , Child , Child, Preschool , Cystinuria/pathology , Female , Humans , Hypercalciuria/pathology , Kidney Calculi/etiology , Male , Patient Selection , Retrospective Studies , Risk Factors , Urolithiasis/etiology
3.
Eur J Surg Oncol ; 41(8): 1082-8, 2015 Aug.
Article in English | MEDLINE | ID: mdl-26033265

ABSTRACT

OBJECTIVE: To evaluate the safety and efficacy of adjuvant intensity-modulated radiotherapy (IMRT) with concurrent paclitaxel and cisplatin (TP) in early stage cervical cancer patients with high risk factors after radical hysterectomy. METHODS: Patients who underwent radical hysterectomy for FIGO stage IB-IIA cervical cancer and had high risk factors for recurrence were recruited. One cycle of TP was delivered before and after concurrent chemoradiotherapy, respectively. Concurrent chemoradiotherapy began 21 days after the start of the initial cycle of the chemotherapy with two cycles of TP delivered on day 1 and day 29 of radiotherapy. Primary endpoints were overall survival (OS) and relapse-free survival (RFS), with toxicities, local-regional control (LC) and distant failure (DF) rate as secondary endpoints. RESULTS: Between 2008 and 2012, 67 patients were evaluable. The 2 and 4-year RFS rates were 98.2% and 92.9%. Corresponding OS rates were 100%, and 98.0%, respectively. The 4-year LC and DF rates were 98.0% and 5.2%, respectively. Grade 3-4 acute leucopenia, neutropenia and thrombocytopenia occurred in 25.4%, 11.9% and 1.5% of patients, respectively. There were 89.6% and 59.7% patients experienced acute vomiting and diarrhea, but only 6.0% and 6.0% patients were grade 3, respectively. No case of chronic toxicity exceeded grade 2. CONCLUSION: Adjuvant concurrent IMRT with paclitaxel plus cisplatin are safe and effective in early stage cervical cancer patients with high risk factors for recurrence following radical hysterectomy.


Subject(s)
Adenocarcinoma/therapy , Cisplatin/administration & dosage , Neoplasm Staging , Paclitaxel/administration & dosage , Radiotherapy, Intensity-Modulated/methods , Uterine Cervical Neoplasms/therapy , Adenocarcinoma/diagnosis , Adenocarcinoma/mortality , Adult , Antineoplastic Agents/administration & dosage , China/epidemiology , Disease-Free Survival , Dose-Response Relationship, Drug , Drug Therapy, Combination , Female , Humans , Hysterectomy , Middle Aged , Retrospective Studies , Risk Factors , Survival Rate/trends , Uterine Cervical Neoplasms/diagnosis , Uterine Cervical Neoplasms/mortality
4.
Drug Discov Today ; 19(3): 289-94, 2014 Mar.
Article in English | MEDLINE | ID: mdl-23973340

ABSTRACT

Confronted with the need to significantly raise the productivity of remotely located chemistry CROs Pfizer embraced a commitment to continuous improvement which leveraged the tools from both Lean Six Sigma and queue management theory to deliver positive measurable outcomes. During 2012 cycle times were reduced by 48% by optimization of the work in progress and conducting a detailed workflow analysis to identify and address pinch points. Compound flow was increased by 29% by optimizing the request process and de-risking the chemistry. Underpinning both achievements was the development of close working relationships and productive communications between Pfizer and CRO chemists.


Subject(s)
Contract Services/organization & administration , Drug Industry/organization & administration , Research/organization & administration , Chemistry, Pharmaceutical/methods , Communication , Contract Services/standards , Drug Design , Drug Discovery/methods , Drug Industry/standards , Efficiency, Organizational , Humans , Quality Improvement , Research/standards , Workflow
5.
Article in English | MEDLINE | ID: mdl-23983324

ABSTRACT

Medicinal plants have been a source of succour in the control of many diseases in developing countries and anaemia is no exception. In this study, ethnomedical survey was carried out for recording medicinal plants used in Northern and South-Eastern Côte d'Ivoire against anaemia. Also iron content was determined for some of the recorded plants using phenanthroline method. Thirty (30) medicinal plants, covering 28 genera and 22 families were recorded. These plants were used to prepare 30 receipts for the treatment of anaemia and aggravating factors such as malaria and gastro-intestinal helminthes. Eleven (11) of these medicinal plants showed presence of iron in various quantities. The most promising were Tectona grandis, Amaranthus spinosus and Stylosanthes erecta which contained the highest iron contents viz; 266.6, 236.6 and 206.6 mg/100 g respectively. They were followed by Hoslundia opposita, Imperata cylindrica, Cajanus cajan, Thalia geniculata and Milicia excelsa. These results lend credence to the traditional use of these plants in Cote d'Ivoire's ethnomedicine for the treatment of anaemia.


Subject(s)
Anemia/drug therapy , Iron/analysis , Magnoliopsida/chemistry , Medicine, African Traditional , Phytotherapy , Plant Extracts/therapeutic use , Plants, Medicinal/chemistry , Adult , Aged , Anemia/complications , Cote d'Ivoire , Gastrointestinal Diseases/complications , Gastrointestinal Diseases/parasitology , Humans , Malaria/complications , Middle Aged , Plant Extracts/chemistry
6.
Science ; 330(6007): 1066-71, 2010 Nov 19.
Article in English | MEDLINE | ID: mdl-20929726

ABSTRACT

Chemokine receptors are critical regulators of cell migration in the context of immune surveillance, inflammation, and development. The G protein-coupled chemokine receptor CXCR4 is specifically implicated in cancer metastasis and HIV-1 infection. Here we report five independent crystal structures of CXCR4 bound to an antagonist small molecule IT1t and a cyclic peptide CVX15 at 2.5 to 3.2 angstrom resolution. All structures reveal a consistent homodimer with an interface including helices V and VI that may be involved in regulating signaling. The location and shape of the ligand-binding sites differ from other G protein-coupled receptors and are closer to the extracellular surface. These structures provide new clues about the interactions between CXCR4 and its natural ligand CXCL12, and with the HIV-1 glycoprotein gp120.


Subject(s)
Receptors, CXCR4/chemistry , Animals , Cell Line , Chemokine CXCL12 , Crystallography, X-Ray , HIV Envelope Protein gp120/metabolism , Humans , Membrane Proteins , Models, Molecular , Protein Binding , Protein Conformation , Protein Multimerization , Receptors, CXCR4/antagonists & inhibitors , Receptors, CXCR4/metabolism , Recombinant Proteins/chemistry , Spodoptera , Thiourea/analogs & derivatives , Thiourea/chemistry
7.
Bioorg Med Chem Lett ; 19(16): 4555-9, 2009 Aug 15.
Article in English | MEDLINE | ID: mdl-19625189

ABSTRACT

Synthesis and structure-activity relationship (SAR) studies on 5-trifluoromethylpyrido[4,3-d]pyrimidin-4(3H)-ones, a novel class of calcium receptor antagonists is described with particular emphasis on optimization of the pharmacokinetic/pharmacodynamic parameters required for a short duration of action compound. Orally-active compounds were identified which displayed the desired animal pharmacology (rapid and transient stimulation of parathyroid hormone) essential for bone anabolic effects.


Subject(s)
Anabolic Agents/chemistry , Pyrimidinones/chemistry , Receptors, Calcium-Sensing/antagonists & inhibitors , Administration, Oral , Anabolic Agents/administration & dosage , Anabolic Agents/pharmacokinetics , Animals , Male , Parathyroid Hormone/metabolism , Pyrimidinones/administration & dosage , Pyrimidinones/pharmacokinetics , Rats , Rats, Sprague-Dawley , Receptors, Calcium-Sensing/metabolism , Structure-Activity Relationship
8.
Bioorg Med Chem Lett ; 18(23): 6071-7, 2008 Dec 01.
Article in English | MEDLINE | ID: mdl-18951788

ABSTRACT

The synthesis and SAR for a series of diaminopyrimidines as PYK2 inhibitors are described. Using a combination of library and traditional medicinal chemistry techniques, a FAK-selective chemical series was transformed into compounds possessing good PYK2 potency and 10- to 20-fold selectivity against FAK. Subsequent studies found that the majority of the compounds were positive in a reactive metabolite assay, an indicator for potential toxicological liabilities. Based on the proposed mechanism for bioactivation, as well as a combination of structure-based drug design and traditional medicinal chemistry techniques, a follow-up series of PYK2 inhibitors was identified that maintained PYK2 potency, FAK selectivity and HLM stability, yet were negative in the RM assay.


Subject(s)
Focal Adhesion Kinase 2/antagonists & inhibitors , Pyrimidines/chemical synthesis , Pyrimidines/pharmacology , Animals , Combinatorial Chemistry Techniques , Crystallography, X-Ray , Disease Models, Animal , Drug Design , Focal Adhesion Protein-Tyrosine Kinases/antagonists & inhibitors , Humans , Molecular Conformation , Molecular Structure , Osteoporosis/drug therapy , Pyrimidines/chemistry , Rats , Structure-Activity Relationship
9.
Trop. j. pharm. res. (Online) ; 7(2): 975-979, 2008.
Article in English | AIM (Africa) | ID: biblio-1273099

ABSTRACT

Purpose: Erigeron floribundus is a reputed medicinal plant used in Cote d'Ivoire; West Africa for the treatment of skin disorders. The aim of this study was to evaluate the antifungal activity of this plant against fungi from human origin. Method: Dichloromethane; methanol 80and aqueous extracts from the leaves with stem were tested for their antifungal activity against 7 strains of dermatophytes (Epidermophyton floccosum; Microsporum canis; M. gypseum; M. langeronii; Trichophyton mentagrophytes; T. rubrum; T. soudanense) and one strain of the filamentous fungus; Scopulariopsis brevicaulis. The assays were performed using the agar dilution method at serial concentrations ranging from 2 to 0.06 mg/ml. Result: Only the dichloromethane extract exhibited an activity against Microsporum canis and a broad spectrum of good antifungal activity against all the remaining fungi tested.Conclusion: To the best our knowledge; this is the first report of the antifungal activity of Erigeron floribundus against a wide range of dermatophytes; including Microsporum langeronii and Trichophyton soudanense; the most frequent dermatophytes in Cote d'Ivoire. E. floribundus might be potential sources for improved traditional medicines or new antidermatophyte agents for the treatment of dermatomycoses


Subject(s)
Anti-Bacterial Agents , Arthrodermataceae , Asteraceae , Erigeron
10.
Neurotox Res ; 12(3): 155-62, 2007 Oct.
Article in English | MEDLINE | ID: mdl-17967739

ABSTRACT

Preclinical and clinical studies have demonstrated that a free radical scavenger edaravone has neuroprotective effects on ischemic stroke but the underlying mechanism is not fully understood. The aim of this research is to explore the effect of edaravone on the apoptotic process involving the Fas/FasL signaling pathway. Transient focal ischemia in rats was induced for 2 hours by middle cerebral artery occlusion (MCAO). After reperfusion rats were treated i.v. with either edaravone or physiological saline. The expression of Fas-associated death domain protein (FADD), death-associated protein (Daxx) and caspase-8 was examined by immunohistochemistry. The mRNA levels for FADD and Daxx by reverse-transcriptase PCR (RT-PCR) and apoptosis was assessed by terminal deoxynucleotidyltransferase-mediated dUTP-biotin nick end labeling (TUNEL). Neurological scores and infarction volumes were also evaluated. Edaravone significantly improved the neurological outcome (p<0.05) and reduced the total infarct volumes (p<0.05), compared with saline control. In addition, edaravone-treatment significantly reduced the number of TUNEL-positive cells (p<0.01), reduced expression levels of FADD, Daxx and caspase-8 immunoreactivity (p <0.05 approximately 0.01), and decreased mRNA levels of FADD and Daxx (p<0.05 approximately 0.01) within the peri-infarct area. We conclude that edaravone may protect ischemic neurons from apoptosis via suppressing the gene expression of the Fas/FasL signaling pathway.


Subject(s)
Antipyrine/analogs & derivatives , Death Domain Receptor Signaling Adaptor Proteins/metabolism , Gene Expression Regulation/drug effects , Ischemic Attack, Transient/drug therapy , Neuroprotective Agents/therapeutic use , Signal Transduction/drug effects , Animals , Antipyrine/therapeutic use , DNA Fragmentation/drug effects , Disease Models, Animal , Edaravone , In Situ Nick-End Labeling , Ischemic Attack, Transient/physiopathology , Male , Neurologic Examination , Rats , Rats, Sprague-Dawley , Statistics, Nonparametric
11.
Org Lett ; 8(23): 5373-6, 2006 Nov 09.
Article in English | MEDLINE | ID: mdl-17078721

ABSTRACT

[Structure: see text] 12-hydroxydaphnetoxins, members of the structurally fascinating daphnane diterpene family, exhibit a wide range of significant biological activities. A general route to the BC-ring system of 12-hydroxy daphnetoxins is reported based on D-ribose. Depending on the choice of protecting groups and solvent, the oxidopyrylium-alkene [5+2] cycloaddition originating from A provides cycloadduct diastereomer B or C with good to excellent selectivity.


Subject(s)
Bridged-Ring Compounds/chemical synthesis , Diterpenes/chemical synthesis , Cyclization , Molecular Structure
12.
J Am Chem Soc ; 124(46): 13648-9, 2002 Nov 20.
Article in English | MEDLINE | ID: mdl-12431074

ABSTRACT

Macrocycle 1 is a new highly potent analogue of bryostatin 1, a promising anti-cancer agent currently in human clinical trials. In vitro, 1 displays picomolar affinity for PKC and exhibits over 100-fold greater potency than bryostatin 1 when tested against various human cancer cell lines. Macrocycle 1 can be generated in clinically required amounts by chemical synthesis in only 19 steps (LLS) and represents a new clinical lead for the treatment of cancer.


Subject(s)
Antineoplastic Agents/chemical synthesis , Lactones/chemical synthesis , Antineoplastic Agents/metabolism , Antineoplastic Agents/pharmacology , Bryostatins , Drug Screening Assays, Antitumor , Humans , Lactones/metabolism , Lactones/pharmacology , Macrolides , Protein Kinase C/metabolism , Tumor Cells, Cultured
13.
Org Lett ; 3(13): 2105-8, 2001 Jun 28.
Article in English | MEDLINE | ID: mdl-11418060

ABSTRACT

[reaction: see text] A concise asymmetric synthesis of the tricyclic core of cyathane diterpenes is described, based on a novel transition-metal-catalyzed intramolecular [5 + 2] cycloaddition of ynone-vinylcyclopropane 10 (assembled from commercially available (S)-(-)-limonene), which proceeds in 90% yield with >95% selectivity. This strategy provides efficient access (14 steps and 13% overall yield) to potential analogues as well as precursors of nerve growth factor (NGF)-inducing diterpenes.


Subject(s)
Diterpenes/chemical synthesis , Cyclohexenes , Diterpenes/chemistry , Diterpenes/pharmacology , Limonene , Nerve Growth Factor/drug effects , Nerve Growth Factor/metabolism , Terpenes/chemistry
14.
Mol Cell Biol ; 21(5): 1463-74, 2001 Mar.
Article in English | MEDLINE | ID: mdl-11238883

ABSTRACT

The dbl oncogene encodes a prototype member of the Rho GTPase guanine nucleotide exchange factor (GEF) family. Oncogenic activation of proto-Dbl occurs through truncation of the N-terminal 497 residues. The C-terminal half of proto-Dbl includes residues 498 to 680 and 710 to 815, which fold into the Dbl homology (DH) domain and the pleckstrin homology (PH) domain, respectively, both of which are essential for cell transformation via the Rho GEF activity or cytoskeletal targeting function. Here we have investigated the mechanism of the apparent negative regulation of proto-Dbl imposed by the N-terminal sequences. Deletion of the N-terminal 285 or C-terminal 100 residues of proto-Dbl did not significantly affect either its transforming activity or GEF activity, while removal of the N-terminal 348 amino acids resulted in a significant increase in both transformation and GEF potential. Proto-Dbl displayed a mostly perinuclear distribution pattern, similar to a polypeptide derived from its N-terminal sequences, whereas onco-Dbl colocalized with actin stress fibers, like the PH domain. Coexpression of the N-terminal 482 residues with onco-Dbl resulted in disruption of its cytoskeletal localization and led to inhibition of onco-Dbl transforming activity. The apparent interference with the DH and PH functions by the N-terminal sequences can be rationalized by the observation that the N-terminal 482 residues or a fragment containing residues 286 to 482 binds specifically to the PH domain, limiting the access of Rho GTPases to the catalytic DH domain and masking the intracellular targeting function of the PH domain. Taken together, our findings unveiled an autoinhibitory mode of regulation of proto-Dbl that is mediated by the intramolecular interaction between its N-terminal sequences and PH domain, directly impacting both the GEF function and intracellular distribution.


Subject(s)
Proto-Oncogene Proteins/chemistry , Proto-Oncogene Proteins/metabolism , 3T3 Cells , Actins/metabolism , Animals , Blotting, Western , COS Cells , Catalytic Domain , Cell Line , Cell Nucleus/metabolism , Cytoskeleton/metabolism , DNA, Complementary/metabolism , Enzyme Activation , Escherichia coli/metabolism , Gene Deletion , Glutathione Transferase/metabolism , Guanine Nucleotide Exchange Factors/metabolism , Guanosine Diphosphate/metabolism , Guanosine Triphosphate/metabolism , Insecta , Mice , Microscopy, Fluorescence , Mutagenesis, Site-Directed , Precipitin Tests , Protein Structure, Tertiary , Recombinant Proteins/metabolism , Stress Fibers/metabolism , Time Factors , Transfection , cdc42 GTP-Binding Protein/metabolism , rho GTP-Binding Proteins/metabolism
15.
Mol Cell Biol ; 21(2): 425-37, 2001 Jan.
Article in English | MEDLINE | ID: mdl-11134331

ABSTRACT

The dbl oncogene product (onco-Dbl) is the prototype member of a family of guanine nucleotide exchange factors (GEFs) for Rho GTPases. The Dbl homology (DH) domain of onco-Dbl is responsible for the GEF catalytic activity, and the DH domain, together with the immediately adjacent pleckstrin homology (PH) domain, constitutes the minimum module bearing transforming function. In the present study, we demonstrate that the onco-Dbl protein exists in oligomeric form in vitro and in cells. The oligomerization is mostly homophilic in nature and is mediated by the DH domain. Mutagenesis studies mapped the region involved in oligomerization to the conserved region 2 of the DH domain, which is located at the opposite side of the Rho GTPase interacting surface. Residue His556 of this region, in particular, is important for this activity, since the H556A mutant retained the GEF catalytic capability and the binding activity toward Cdc42 and RhoA in vitro but was deficient in oligomer formation. Consequently, the Rho GTPase activating potential of the H556A mutant was significantly reduced in cells. The focus-forming and anchorage-independent growth activities of onco-Dbl were completely abolished by the His556-to-Ala mutation, whereas the abilities to stimulate cell growth, activate Jun N-terminal kinase, and cause actin cytoskeletal changes were retained by the mutant. The ability of onco-Dbl to oligomerize allowed multiple Rho GTPases to be recruited to the same signaling complex, and such an ability is defective in the H556A mutant. Taken together, these results suggest that oligomerization of onco-Dbl through the DH domain is essential for cellular transformation by providing the means to generate a signaling complex that further augments and/or coordinates its Rho GTPase activating potential.


Subject(s)
Cell Transformation, Neoplastic , Retroviridae Proteins, Oncogenic/chemistry , Retroviridae Proteins, Oncogenic/metabolism , 3T3 Cells , Actins/metabolism , Animals , Cell Division , Cytoskeleton/metabolism , Enzyme Activation , Guanine Nucleotide Exchange Factors/metabolism , JNK Mitogen-Activated Protein Kinases , Kinetics , Mice , Microscopy, Fluorescence , Mitogen-Activated Protein Kinases/metabolism , Models, Molecular , Mutagenesis, Site-Directed , Mutation/genetics , Protein Binding , Protein Structure, Quaternary , Protein Structure, Tertiary , Recombinant Fusion Proteins , Retroviridae Proteins, Oncogenic/genetics , Signal Transduction , Transfection , cdc42 GTP-Binding Protein/metabolism , rho GTP-Binding Proteins/genetics , rho GTP-Binding Proteins/metabolism
16.
Cancer Gene Ther ; 8(11): 835-42, 2001 Nov.
Article in English | MEDLINE | ID: mdl-11773973

ABSTRACT

The c-erbB-2/neu-encoded protein p185 is closely related to the growth and metastasis of adenocarcinoma. We sought to reverse the malignant phenotype of gastric cancer cell line SGC7901 with c-erbB-2-specific ribozyme. We designed the ribozyme and generated the in vitro transcription vectors of the ribozyme and its substrate. In vitro cleavage reaction indicated that the ribozyme catalyzed 79.3% target RNA in 1 hour at 37 degrees C. Then, we generated the eucaryotic expression vectors of the ribozyme and transfected them into SGC7901 cells, which highly express p185. Analyses showed that the c-erbB-2 mRNA and p185 were reduced remarkably in the ribozyme-transfected cells. The growth rate of the ribozyme-transfected cells was much lower than that of the control group. Tumorigenicity was also decreased dramatically in nude mice. The results demonstrated that c-erbB-2-specific ribozyme may inhibit the malignancy of gastric cancer cells SGC7901.


Subject(s)
Adenocarcinoma/therapy , Genes, erbB-2/genetics , RNA, Antisense/therapeutic use , RNA, Catalytic/therapeutic use , Stomach Neoplasms/therapy , Adenocarcinoma/genetics , Adenocarcinoma/pathology , Animals , Base Sequence , Female , Genetic Therapy , Humans , Mice , Mice, Inbred BALB C , Mice, Nude , Molecular Sequence Data , Phenotype , Plasmids , RNA, Catalytic/genetics , RNA, Messenger/antagonists & inhibitors , RNA, Messenger/metabolism , Stomach Neoplasms/genetics , Stomach Neoplasms/pathology , Transfection , Tumor Cells, Cultured
18.
Org Lett ; 2(11): 1529-31, 2000 Jun 01.
Article in English | MEDLINE | ID: mdl-10841471

ABSTRACT

[reaction--see text] This paper describes a catalytic, asymmetric approach to the C(1)(')-C(10)(') segment of pamamycin 621A. We synthesize this segment in a convergent manner, with each of the coupling partners ultimately deriving from enantiomerically enriched methylketene dimer.


Subject(s)
Antifungal Agents/chemistry , Anti-Bacterial Agents/chemical synthesis , Anti-Bacterial Agents/chemistry , Antifungal Agents/chemical synthesis , Antitubercular Agents/chemical synthesis , Antitubercular Agents/chemistry , Catalysis , Macrolides , Organic Chemicals , Stereoisomerism
19.
Zhonghua Yi Xue Za Zhi ; 79(4): 295-7, 1999 Apr.
Article in Chinese | MEDLINE | ID: mdl-11601058

ABSTRACT

OBJECTIVE: To probe the effect of c-erbB-2 specific ribozyme to the malignant phenotype of gastric cancer. METHODS: The eucaryotic expression vector of c-erbB-2 specific ribozyme RZ1 was designed by computer and named pDOR-RZ1. The transfection of the gastric cancer cell line SGC-7901 was mediated by Lipofect AMINE. Flow cytometry was used to analyse the expression of the c-erbB-2 product P185. In vivo study of tumorogenecity of the transfected cells was performed in nude mice. RESULTS: pDOR-RZ1 was successfully transfected into the gastric cancer cell line SGC-7901 and then the single clones were selected by G418 and named SGC/RZ1. Flow cytometry analysis showed that the expression of P185 was suppressed by 62.7%. The growth rate of SGC/RZ1 was inhibited by 55%. The tumor-forming time in SGC/RZ1 in nude mice was delayed remarkably and the tumor size was also much smaller than that in the control group, indicating the inhibition of the tumorogenecity of SGC/RZ1 in nude mice. CONCLUSION: c-erbB-2 specific ribozyme is very efficient in reversing the malignant phenotype of gastric cancer. This might provide a new approach for gene therapy of gastric cancer.


Subject(s)
Receptor, ErbB-2/biosynthesis , Stomach Neoplasms/genetics , Stomach Neoplasms/pathology , Animals , Humans , Mice , Mice, Inbred BALB C , Mice, Nude , Phenotype , RNA, Catalytic/biosynthesis , RNA, Catalytic/genetics , Receptor, ErbB-2/genetics , Transfection , Tumor Cells, Cultured
20.
Zhonghua Zhong Liu Za Zhi ; 21(1): 7-9, 1999 Jan.
Article in Chinese | MEDLINE | ID: mdl-11776804

ABSTRACT

OBJECTIVE: To construct in vitro transcription vectors of genes of c-erbB-2 specific ribozyme and its substrate and to probe its in vitro cleavage action. METHODS: According to the computer design, a specific restriction site EcoR V was added to the 3' end of the ribozyme gene (RZ1). Then, the RZ1 gene and its substrate gene were cloned into the in vitro transcription vector pGEM3Zf(-) separately. The recombinants containing RZ1 gene were first screened by agrose ge1 electrophoresis through EcoR V digestion and was identified by automatic sequencing. The products of in vitro transcription were labeled with 32P. In vitro cleavage reaction was performed at 37 degrees C for 1 h under the presence of Mg++. The cleavage product was analyzed by polyacrilamide gel electrophoresis. After autoradiography, the cleavage rate was counted by image analysis. RESULTS: The recombinants containing the RZ1 gene were successfully selected by the EcoR V digestion and were designated as pGM3Z-RZ1. The automatic sequence analysis proved that the synthesized RZ1 gene was correct. The target gene was also cloned into the pGEM3Zf(-) under SP6 promoter. After in vitro transcription, the cleavage reaction was shown to have cut off 79.3% target RNA in 1 h. CONCLUSION: The c-erbB-2 oncogene-specific ribozyme has a high activity in vitro. It lays a foundation for the study of the therapeutic use of ribozyme in gene therapy of cancer.


Subject(s)
Genes, erbB-2 , RNA, Catalytic/pharmacology , Genetic Therapy , RNA, Catalytic/therapeutic use
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