ALBERT

All Library Books, journals and Electronic Records Telegrafenberg

feed icon rss

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
Filter
  • Articles  (31)
  • chemoprevention  (31)
  • Wiley-Blackwell  (31)
  • Medicine  (31)
  • Political Science
Collection
  • Articles  (31)
Publisher
Years
Topic
  • 1
    Electronic Resource
    Electronic Resource
    New York, N.Y. : Wiley-Blackwell
    Journal of Cellular Biochemistry 67 (1997), S. 125-132 
    ISSN: 0730-2312
    Keywords: chemoprevention ; cervical intraepithelial neoplasia (CIN) ; surrogate endpoint biomarker (SEB) ; α-difluoromethylornithine (DFMO) ; Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Chemistry and Pharmacology , Medicine
    Notes: Cervical cancer remains a significant health problem. New strategies based on the molecular aspects of cervical carcinogenesis are needed. Chemoprevention represents a novel strategy for cervical cancer prevention. Our group plans phase I and II trials using α-difluoromethylornithine, a suicide inhibitor of ornithine decarboxylase and potent antiproliferative chemopreventive agent. We conducted a study to identify which polyamines in tissue could best serve as surrogate endpoint biomarkers for future trials. Thirty patients with biopsy-proven cervical intraepithelial neoplasia grade 3 underwent colposcopically directed biopsies of normal and abnormal areas of the uterine cervix for analysis of polyamine synthesis biomarkers. Statistically significant differences were found in the ornithine decarboxylase value and the spermidine:spermine ratio between normal and abnormal areas of the cervix. In general, the ranges in measurements varied widely. Differences in polyamine synthesis biomarkers between colposcopically normal and abnormal areas can be demonstrated. However, studies using polyamine synthesis biomarkers in the cervix would require large numbers of patients to achieve significance. J. Cell. Biochem. Suppls. 28/29:125-132. Published 1998 Wiley-Liss, Inc.This article is a US Government work and, as such, is in the public domain in the United States of America.
    Additional Material: 1 Ill.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 2
    Electronic Resource
    Electronic Resource
    New York, N.Y. : Wiley-Blackwell
    Journal of Cellular Biochemistry 50 (1992), S. 51-54 
    ISSN: 0730-2312
    Keywords: aberrant crypts ; azoxymethane ; chemoprevention ; colorectal cancer ; intermediate biomarker ; NSAID ; piroxicam ; Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Chemistry and Pharmacology , Medicine
    Notes: Single and multiple colonic crypts exhibiting dysplasia that are detectable in situ by staining of rat colon with methylene blue are called aberrant crypts (AC) and may serve as an intermediate marker for colon cancer. In a characterization study, we have established the kinetics of AC growth and development over a period of 20 d following injection of rats with the carcinogen azoxymethane (AOM). AC are not present at 5 d post-injection, but are a constant feature at 10 d and thereafter. Multiple AC, presumably clonal, begin to evolve at 10 d and are consistent by 20 d, forming incipient microdenomata. We have examined 20 candidate chemopreventive agents for inhibition of AC. All agents were given in AIN-76diet, at two dose levels, with injections of AOM. AC were measured after 5 weeks of growth. Among the most active AC-inhibiting agents were BHA, DFMO, quercetin, diallyl sulfide, 18β-glycyrrhetinic acid, and ascorbyl palmitate. In a postinitiation study, the differentiating agent sodium butyrate was ineffective, but piroxicam was highly effective in modulating AC growth. Further, piroxicam inhibited AC development at all stages of growth from single to polycryptal clusters of AC. The AC assay shows marked sensitivity and specificity for screening agents for chemoprevention of colon cancer. © 1992 Wiley-Liss, Inc.
    Additional Material: 1 Ill.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 3
    ISSN: 0730-2312
    Keywords: biomarkers ; chemoprevention ; premalignancy ; prostate ; randomized trials ; risk stratification ; Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Chemistry and Pharmacology , Medicine
    Notes: The “natural history” of prostate cancer may bedevil the development of guidelines for chemoprevention interventions. Can strategies be designed to direct agents to those lesions which have the potential to develop localized extension that may become symptomatic or metastatic disease? Of necessity our interventions will focus on the identification and quantification of appropriate biomarkers as intermediate endpoints, although no reliable endpoints for prostate cancer have yet been identified. The reduction of prostate cancer incidence may be the ultimate objective, but a decrease in the progression of microfocal or “latent” cancer may well be just as effective as prevention when the age of the target population and competing causes of death are taken into account. Early intervention strategies must focus on the analysis of the interactions of the chosen chemopreventive agents upon precancerous and cancerous cellular dynamics in the prostate. Whether the requirements of such molecular epidemiology necessitate a more deliberate strategy of Phase II studies or a high-risk gain strategy of a broad Phase III study is open to debate. Factorial designs for proposed randomized chemoprevention trials may be desirable to test multiple chemopreventive agents simultaneously, provided knowledge of the biochemical synergism of the agent is solid. Stratification of study participants by degree of risk will ameliorate concerns regarding the precision targeting of lesions at different stages in the precancer/cancer continuum.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 4
    Electronic Resource
    Electronic Resource
    New York, N.Y. : Wiley-Blackwell
    Journal of Cellular Biochemistry 59 (1995), S. 117-125 
    ISSN: 0730-2312
    Keywords: AIDS ; anticarcinogen ; antiviral ; chemoprevention ; dithiolethiones ; glutathione ; reverse transcriptase ; Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Chemistry and Pharmacology , Medicine
    Notes: Glutathione (GSH) levels are markedly depleted in patients infected with human immunodeficiency virus type 1 (HIV-1) and supplementation of media with high concentrations (5-20 mM) of low-molecular weight thiols prevents HIV-1 replication in cultured cells. We were intrigued whether chemo-preventive enzyme inducers might represent a more pharmacologically feasible method to inhibit HIV-1 replication since these compounds elevate intracellular concentrations of GSH at nontoxic doses in vivo. After establishing that all inducers surveyed were able to elevate GSH levels in human T-cell and monocytoid cell lines, we were surprised to find that olitpraz (5-pyrazinyl-4-methyl-1,2-dithiole-3-thione) was uniquely able to inhibit HIV-1 replication (IC50 = 5-15 μM). Oltipraz and other antiviral 1,2-dithiole-3-thiones (DTTs) appear to inhibit acute HIV-1 replication by inactivating reverse transcriptase (RT). However, among DTTs that inhibit HIV-1 replication in acutely infected cells, only oltipraz was able to inhibit HIV-1 replication in a chronic infection model. Thus, in addition to inactivating RT, oltipraz appears to have an additional antiviral mechanism distal to viral integration. Our laboratories are attempting to determine the mechanism by which oltipraz inhibits HIV-1 replication in chronically infected cells; we are also attempting to determine the bioorganic mechanism for the inactivation of RT. Since the covalent modification of schistosomal protein and transcription factor(s) are thought to be responsible for the antiparasitic and chemopreventive activities of DTTs, respectively, our studies should be relevant to understanding the diverse medicinal properties of DTTs. Oltipraz, an antischistosomal drug undergoing clinical evaluation as an anticarcinogen, inhibits HIV-1 replication at concentrations achievable in human serum. It is intriguing to consider oltipraz as a therapeutic agent not only for its antiretroviral activity, but also for the prevention of HIV-1 associated neoplasms.
    Additional Material: 3 Ill.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 5
    ISSN: 0730-2312
    Keywords: bladder cancer ; chemoprevention ; MNU ; model systems ; mouse ; OH-BBN ; rat ; retinoids ; Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Chemistry and Pharmacology , Medicine
    Notes: The chemopreventive efficacy of several compounds was evaluated in the N-butyl-N-(4-hydroxybuty) introsamine (OH)-BBN)-induced urinary bladder cancer model using C57BL/6xDBA/2F1 (BDF) male mice. Compounds were administered in a defined semipurified diet (AIN-76-A) either as single agents orin combination. As single agents and at the doses emplyed, 2-α-difluoromethylornithine (DFMO), piroxicam, oltpraz, and sodium moybdate effectively inhibited the incidence of trasitional cell carcinoma (TCC). 4-Hydroxyphenyl retinamide (4-HPR) was ineffective. Body weight gain and survival was not affected by thedoses of agents used. Combinations of two agents which increased efficacy were 4-HPR+DFMO, DFMO+piroxicam, 4-HPR+oltipraz, and DFMO+oltiprz. Three-agent combinations which showed enhanced efficacy against TCC induction were 4-HPR+Namolybdate+DFMO, 4-HPR+DFMO+piroxicam, and 4-HPR+DFMO+oltipraz. Although the three-agent combinations were, for the most part, no more effective than the two-agent combinations at the doses employed, all combination regmens signicantly reduced bladder incidence even when single agent administration did not. © 1992 Wiley-Liss, Inc.
    Additional Material: 1 Tab.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 6
    ISSN: 0730-2312
    Keywords: Animal models ; carcinogenesis ; chemoprevention ; drug development ; Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Chemistry and Pharmacology , Medicine
    Notes: In the NCI, Chemoprevention Branch drug development program, potential chemopreventive agents are evaluated for efficacy against chemical carcinogen-induced tumors in animal models. This paper summarizes the results of 144 agents in 352 tests using various animal efficacy models. Of these results, 146 were positive, representing 85 different agents.The target organs selected for the animals model are representative of high-incidence human cancers. The assays include inhibition of tumors induced by MNU in hamster trachea, DEN in hamster lung, AOM in rat colon (including inhibition of AOM-induced aberrant crypts), MAM in mouse colon, DMBA and MNU in rat mammary glands, DMBA promoted by TPA in mouse skin, and OH-BBN in mouse bladder.The agents tested may be classified into various pharmacological and chemical structural categories that are relevant to their chemopreventive potential. These categories include antiestrogens, antiinflammatories (e. g., NSAIDs), antioxidants, arachidonic acid metabolism inhibitors, GST and GSH enhancers, ODC inhibitors, protein kinase C inhibitors, retinoids and carotenoids, organosulfur compounds, calcium compounds, vitamin D3 and analogs, and phenolic compounds (e. g., flavonoids). The various categories of compounds have different spectra of efficacy in animal models. In hamster lung, GSH-enhancing agents and antioidants appear to have high potential for inhibiting carcinogenesis. In the colon, NSAIDs and other antiinflammatory agents appear particularly promising. Likewise, NSAIDs are very active in mouse bladder. In rat mammary glands, retinoids and antiestrogens (as would be expected) are efficacious. Several of the chemicals evaluated also appear to be promising chemopreventive agents based on their activity in several of the animal models. Particularly, the ODC inhibitor DFMO was active in the colon, mammary glands, and bladder models, while the dithiolthione, oltipraz, was efficacious in all the models listed above (i. e., lung, colon, mammary glands, skin, and bladder). 1994 Wiley-Liss, Inc.This article is a US Government work and, as such, is in the public domain in the United States of America.
    Additional Material: 1 Tab.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 7
    ISSN: 0730-2312
    Keywords: two-dimensional gel electrophoresis ; cervical cancer ; genomic alterations ; genomic scanning ; chemoprevention ; Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Chemistry and Pharmacology , Medicine
    Notes: Two-dimensional gel electrophoresis was used to comprehensively scan the whole genome of 6 cervical intraepithelial neoplasia (CIN) lesions, 7 cervical squamous cell carcinomas, 1 cervical adenosquamous cell carcinoma, and 2 cervical adenocarcinomas for multiple genetic alterations, such as DNA amplification, chromosome deletion, loss of heterozygosity, and chromosome translocation, as compared with the paired normal tissues. DNA spot analysis of the genomic 2-dimensional gels was performed by a computer color overlay system and by spot recognition software allowing for objective spot comparison and quantitation. Nine spots were found to be amplified in the cervical carcinomas while two amplified spots were detected in the CIN III lesions. Fourteen DNA spots were either reduced in their intensity or absent in cervical carcinomas as compared to their normal paired tissues. Reduction of intensity in 6 spots was observed in the 5 CIN III lesions. These genetic alterations may represent changes in cancer genes that are associated with human cervical carcinogenesis. Further characterization of these alterations may be significant to the understanding of cervical tumorigenesis and to the development of biomarkers for clinical trials in cancer chemoprevention. J. Cell. Biochem. 25S:41-48. © 1997 Wiley-Liss, Inc.
    Additional Material: 3 Ill.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 8
    Electronic Resource
    Electronic Resource
    New York, N.Y. : Wiley-Blackwell
    Journal of Cellular Biochemistry 50 (1992), S. 148-152 
    ISSN: 0730-2312
    Keywords: 13-cis- retinoic acid ; bladder carcinoma ; chemoprevention ; Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Chemistry and Pharmacology , Medicine
    Notes: Animal studies indicate that 13-cis-retinoic acid (CRA) inhibits bladde tumor growth and is effedctive in treating patients with serious dermatologic disorders. A trial of CRA in patients at high risk for rec urrent, TA, T1 tumors was initiated at an experiemtnal dose o f0.5 mg/kg/d in three divided doeses, increasing to 1/mg/kg/d at foru weeks. Treatment of twenty eligible patients lasted for six months with an additional 24 month follow-up period. One patient was later excluded due to toxicity resulting in an early dose a reductionm.Eight patients stopped treatment before three months; of these five, had recurrences swithin three months, one developed pulmonary metastasis, and one developed a T2G3 tumore. Four patients stopped treatment between three and six months; three of them had rercurrences before one year and one had no evidence of disease years. Seven patients completed the course; of these three had recurrences within six months, and three more had recurrences at 8, 15, and 45 months, respectively.Toxicity was nearly universal; cheilosis, conjuctivitis, joint and eye pain, flashing lights, and erythrocyte sedimentation rate (ESR) over 60 were all noted. The lack of positive resutls and the frequency and severity of toxicity led to termination of the study. © 1992 Wiley-Liss, Inc.
    Additional Material: 2 Tab.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 9
    Electronic Resource
    Electronic Resource
    New York, N.Y. : Wiley-Blackwell
    Journal of Cellular Biochemistry 53 (1993), S. 57-65 
    ISSN: 0730-2312
    Keywords: Cancer detection ; chemoprevention ; chest x-rays ; cigarette smoking ; lung cancer ; sputum cytology ; Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Chemistry and Pharmacology , Medicine
    Notes: Carcinoma of the lung is the most common cause of death from cancer in the United States. In considering lung cancer for possible chemoprevention trials, we have analyzed the data collected by the collaborative NCI program on early lung cancer. The data indicate that at least 12 years of study of 80,000 people at risk for lung cancer (adult male cigarette smokers) would be required to establish a 25% reduction in squamous carcinoma of the lung. No intermediate markers of developing lung cancer are presently available to shorten the observation period. It is concluded that a study of the magnitude required is not feasible at the present time.
    Additional Material: 4 Ill.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 10
    Electronic Resource
    Electronic Resource
    New York, N.Y. : Wiley-Blackwell
    Journal of Cellular Biochemistry 53 (1993), S. 83-90 
    ISSN: 0730-2312
    Keywords: intermediate biomarkers ; chemoprevention ; biological ; molecular ; genetic changes ; hamster ; buccal pouch ; Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Chemistry and Pharmacology , Medicine
    Notes: The Syrian golden hamster cheek pouch carcinogenesis model is probably the best-known animal system that closely compares to events involved in the development of premalignant and malignant human oral cancers. Furthermore, it is one of the most well-characterized models for squamous cell carcinomas (SCCs). However, stages of carcinogenesis (initiation, promotion, and progression) have not been well-defined in this system. Basic understanding of the mechanism(s) of carcinogenesis in this organ is instrumental for the development of new strategies for chemoprevention and early chemointervention. To understand the important early events that occur in the hamster cheek pouch carcinogenesis model, we compared it to the mouse skin model, where a number of critical events have been well characterized. We determined that approximately 60% of the hamster cheek pouch SCCs have a mutation in codon 61 of the Ha-ras gene. We also established a two-stage carcinogenesis protocol in this model using a single dose of dimethylbenz(a)anthracene (DMBA) and multiple doses of benzoyl peroxide for 45 weeks. Twenty-five percent of tumors developed with this protocol had the same mutation in codon 61 of the Ha-ras gene, confirming that this mutation, as in the mouse skin model, is initiation-related. We examined the sequential expression of hyperplasia, micronucleated cells, ornithine decarboxylase (ODC) activity, polyamine levels, transglutaminase I activity, epidermal growth factor receptor (EGF-R) levels, keratins, γ-glutamyltranspeptidase (GGT), transforming growth factor -β1 (TGF-β1), leukoplakia, and carcinomas induced during carcinogenesis. A number of these important biological molecular and genetic markers could be excellent intermediate endpoints in assessing the effects of various chemopreventive agents to be tested in the hamster cheek pouch model and in human clinical trials.
    Additional Material: 4 Tab.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...