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1.
J Pharm Pract ; : 8971900221135656, 2022 Nov 11.
Artigo em Inglês | MEDLINE | ID: mdl-36367838

RESUMO

Background: In 2016, the FDA issued a warning for saxagliptin and alogliptin regarding an increased risk of heart failure (HF), potentially limiting the use of effective medications in type 2 diabetes. Current data and guideline recommendations regarding HF risk are conflicting, especially with alogliptin. In March 2019, the Memphis Veterans Affairs Medical Center made a formulary change from saxagliptin to alogliptin, creating an opportunity to evaluate a large number of patients receiving alogliptin. Objective: To evaluate the risk of HF with alogliptin use in type 2 diabetes patients. Methods: A retrospective chart review of patients prescribed alogliptin was performed. The primary outcome was the composite number of HF hospital admissions and ED visits. Secondary outcomes included exacerbation rates among established HF patients, incidence of new-onset HF, incidence of alogliptin discontinuation due to HF, comparison of HF exacerbations between saxagliptin and alogliptin in patients with prior saxagliptin use, and evaluation of concomitant cardiotoxic medications. Results: 455 patients were included. A composite of 28 hospital admissions and ED visits occurred for a HF exacerbation. Fourteen patients (26.4%) of 53 patients with established HF had an exacerbation, whereas 5 patients (1.2%) of 402 patients with no history of HF had an exacerbation. Eight patients (2%) developed new-onset HF. Alogliptin was discontinued in 4 patients (0.9%) due to HF. No statistically significant difference in HF exacerbations was found between patients on alogliptin who previously received saxagliptin (4.8% vs 4.2%, P = 0.726). Conclusions: Alogliptin may increase the risk of HF exacerbation in patients with established HF.

2.
BMC Genomics ; 19(1): 893, 2018 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-30526477

RESUMO

BACKGROUND: The core functions of the insulin/insulin-like signaling and target of rapamycin (IIS/TOR) pathway are nutrient sensing, energy homeostasis, growth, and regulation of stress responses. This pathway is also known to interact directly and indirectly with the sex determination regulatory hierarchy. The IIS/TOR pathway plays a role in directing sexually dimorphic traits, including dimorphism of growth, metabolism, stress and behavior. Previous studies of sexually dimorphic gene expression in the adult head, which includes both nervous system and endocrine tissues, have revealed variation in sex-differential expression, depending in part on genotype and environment. To understand the degree to which the environmentally responsive insulin signaling pathway contributes to sexual dimorphism of gene expression, we examined the effect of perturbation of the pathway on gene expression in male and female Drosophila heads. RESULTS: Our data reveal a large effect of insulin signaling on gene expression, with greater than 50% of genes examined changing expression. Males and females have a shared gene expression response to knock-down of InR function, with significant enrichment for pathways involved in metabolism. Perturbation of insulin signaling has a greater impact on gene expression in males, with more genes changing expression and with gene expression differences of larger magnitude. Primarily as a consequence of the response in males, we find that reduced insulin signaling results in a striking increase in sex-differential expression. This includes sex-differences in expression of immune, defense and stress response genes, genes involved in modulating reproductive behavior, genes linking insulin signaling and ageing, and in the insulin signaling pathway itself. CONCLUSIONS: Our results demonstrate that perturbation of insulin signaling results in thousands of genes displaying sex differences in expression that are not differentially expressed in control conditions. Thus, insulin signaling may play a role in variability of somatic, sex-differential expression. The finding that perturbation of the IIS/TOR pathway results in an altered landscape of sex-differential expression suggests a role of insulin signaling in the physiological underpinnings of trade-offs, sexual conflict and sex differences in expression variability.


Assuntos
Drosophila melanogaster/genética , Regulação da Expressão Gênica no Desenvolvimento , Insulina/metabolismo , Caracteres Sexuais , Transdução de Sinais , Serina-Treonina Quinases TOR/metabolismo , Animais , Éxons/genética , Feminino , Masculino , Receptor de Insulina/metabolismo
3.
Am J Health Promot ; 32(5): 1239-1247, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-28731384

RESUMO

PURPOSE: Adolescent tobacco use is higher in rural than in urban areas. While e-cigarette use is increasing rapidly among this age group, differences in prevalence between rural versus urban populations for this relatively novel product have not been explored. The purpose is to investigate whether location of school (rural-urban) is associated with e-cigarette use and dual use (defined as the use of both e-cigarettes and conventional cigarettes) among high school students. DESIGN: Cross-sectional survey obtained using a stratified, 3-stage cluster sample design. SETTING: United States. PARTICIPANTS: A nationally representative sample of US high school students (N = 11 053) who completed the 2014 National Youth Tobacco Survey (NYTS); slightly more than half were urban (54%). MEASURES: The NYTS measures tobacco-related knowledge, attitudes, and use behavior and demographics of students in the United States. ANALYSIS: Weighted logistic regression assessed the relationships of urban-rural location with current e-cigarette use and dual use, adjusting for demographic factors, perceived risk, and social norms. RESULTS: There were clear differences in patterns of adolescent e-cigarette and cigarette use in rural versus urban areas. Social norms and perceptions may play a role in understanding these differences. CONCLUSION: Urban youth current cigarette smokers were nearly twice as likely as rural cigarette smokers to also use e-cigarettes. Reasons for urban-rural differences need to be taken into account when designing prevention programs and policy changes.


Assuntos
Comportamento do Adolescente/psicologia , Fumar Cigarros/psicologia , Sistemas Eletrônicos de Liberação de Nicotina/estatística & dados numéricos , População Rural/estatística & dados numéricos , Estudantes/psicologia , Estudantes/estatística & dados numéricos , População Urbana/estatística & dados numéricos , Adolescente , Estudos Transversais , Feminino , Humanos , Masculino , Vigilância da População , Inquéritos e Questionários , Estados Unidos
5.
BMC Genomics ; 18(1): 191, 2017 02 20.
Artigo em Inglês | MEDLINE | ID: mdl-28219347

RESUMO

Advancing the production efficiency and profitability of aquaculture is dependent upon the ability to utilize a diverse array of genetic resources. The ultimate goals of aquaculture genomics, genetics and breeding research are to enhance aquaculture production efficiency, sustainability, product quality, and profitability in support of the commercial sector and for the benefit of consumers. In order to achieve these goals, it is important to understand the genomic structure and organization of aquaculture species, and their genomic and phenomic variations, as well as the genetic basis of traits and their interrelationships. In addition, it is also important to understand the mechanisms of regulation and evolutionary conservation at the levels of genome, transcriptome, proteome, epigenome, and systems biology. With genomic information and information between the genomes and phenomes, technologies for marker/causal mutation-assisted selection, genome selection, and genome editing can be developed for applications in aquaculture. A set of genomic tools and resources must be made available including reference genome sequences and their annotations (including coding and non-coding regulatory elements), genome-wide polymorphic markers, efficient genotyping platforms, high-density and high-resolution linkage maps, and transcriptome resources including non-coding transcripts. Genomic and genetic control of important performance and production traits, such as disease resistance, feed conversion efficiency, growth rate, processing yield, behaviour, reproductive characteristics, and tolerance to environmental stressors like low dissolved oxygen, high or low water temperature and salinity, must be understood. QTL need to be identified, validated across strains, lines and populations, and their mechanisms of control understood. Causal gene(s) need to be identified. Genetic and epigenetic regulation of important aquaculture traits need to be determined, and technologies for marker-assisted selection, causal gene/mutation-assisted selection, genome selection, and genome editing using CRISPR and other technologies must be developed, demonstrated with applicability, and application to aquaculture industries.Major progress has been made in aquaculture genomics for dozens of fish and shellfish species including the development of genetic linkage maps, physical maps, microarrays, single nucleotide polymorphism (SNP) arrays, transcriptome databases and various stages of genome reference sequences. This paper provides a general review of the current status, challenges and future research needs of aquaculture genomics, genetics, and breeding, with a focus on major aquaculture species in the United States: catfish, rainbow trout, Atlantic salmon, tilapia, striped bass, oysters, and shrimp. While the overall research priorities and the practical goals are similar across various aquaculture species, the current status in each species should dictate the next priority areas within the species. This paper is an output of the USDA Workshop for Aquaculture Genomics, Genetics, and Breeding held in late March 2016 in Auburn, Alabama, with participants from all parts of the United States.


Assuntos
Aquicultura/métodos , Cruzamento/métodos , Genômica/métodos , Animais , Mapeamento Cromossômico , Variação Genética , Estados Unidos
6.
G3 (Bethesda) ; 6(7): 1799-808, 2016 07 07.
Artigo em Inglês | MEDLINE | ID: mdl-27172187

RESUMO

Sex differences in gene expression have been widely studied in Drosophila melanogaster Sex differences vary across strains, but many molecular studies focus on only a single strain, or on genes that show sexually dimorphic expression in many strains. How extensive variability is and whether this variability occurs among genes regulated by sex determination hierarchy terminal transcription factors is unknown. To address these questions, we examine differences in sexually dimorphic gene expression between two strains in Drosophila adult head tissues. We also examine gene expression in doublesex (dsx) mutant strains to determine which sex-differentially expressed genes are regulated by DSX, and the mode by which DSX regulates expression. We find substantial variation in sex-differential expression. The sets of genes with sexually dimorphic expression in each strain show little overlap. The prevalence of different DSX regulatory modes also varies between the two strains. Neither the patterns of DSX DNA occupancy, nor mode of DSX regulation explain why some genes show consistent sex-differential expression across strains. We find that the genes identified as regulated by DSX in this study are enriched with known sites of DSX DNA occupancy. Finally, we find that sex-differentially expressed genes and genes regulated by DSX are highly enriched on the fourth chromosome. These results provide insights into a more complete pool of potential DSX targets, as well as revealing the molecular flexibility of DSX regulation.


Assuntos
Proteínas de Ligação a DNA/genética , Proteínas de Drosophila/genética , Drosophila melanogaster/genética , Regulação da Expressão Gênica no Desenvolvimento , Caracteres Sexuais , Processos de Determinação Sexual , Transcriptoma , Animais , Mapeamento Cromossômico , DNA/genética , DNA/metabolismo , Proteínas de Ligação a DNA/metabolismo , Proteínas de Drosophila/metabolismo , Drosophila melanogaster/crescimento & desenvolvimento , Drosophila melanogaster/metabolismo , Feminino , Masculino , Proteínas do Tecido Nervoso/genética , Proteínas do Tecido Nervoso/metabolismo , Proteínas Nucleares/genética , Proteínas Nucleares/metabolismo , Ligação Proteica , Mapeamento de Interação de Proteínas , Proteínas de Ligação a RNA/genética , Proteínas de Ligação a RNA/metabolismo , Ribonucleoproteínas/genética , Ribonucleoproteínas/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo
7.
Bioorg Med Chem ; 12(23): 6221-36, 2004 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-15519165

RESUMO

The synthesis, DNA binding properties, and in vitro and in vivo anticancer activity of fifteen achiral seco-cyclopropylindoline (or achiral seco-CI) analogs (5a-o) of CC-1065 and the duocarmycins are described. The achiral seco-CI analogs contain a 4-hydroxyphenethyl halide moiety that is attached to a wide range of indole, benzimidazole, pyrrole, and pyridyl-containing noncovalent binding components. The 4-hydroxyphenethyl halide moiety represents the simplest mimic of the seco-cyclopropylpyrroloindoline (seco-CPI) pharmacophore found in the natural products, and it lacks a chiral center. The sequence and minor groove specificity of the achiral compounds was ascertained using a Taq DNA polymerase stop assay and a thermal induced DNA cleavage experiment using either a fragment of pBR322 or pUC18 plasmid DNA. For example, seco-CI-InBf (5a) and seco-CI-TMI (5c) demonstrated specificity for AT-rich sequences, particularly by reacting with the underlined adenine-N3 position of 5'-AAAAA(865)-3'. This is also the sequence that CC-1065 and adozelesin prefer to alkylate. The achiral seco-CI compounds were subjected to cytotoxicity studies against several human (K562, LS174T, PC3, and MCF-7) and murine cancer cell lines (L1210 and P815). Following continuous drug exposure, the achiral compounds were found to be cytotoxic, with IC(50) values in the muM range. Interestingly, the carbamate protected compound 5p was significantly less cytotoxic than agent 5c, supporting the hypothesis that loss of HCl and formation of a spiro[2,5]cyclopropylcyclohexadienone intermediate is necessary for biological activity. The achiral seco-CI compounds 5a and 5c were submitted to the National Cancer Institute for further cytotoxicity screening against a panel of 60 different human cancer cell lines. Both compounds showed significant activity, particularly against several solid tumor cell lines. Flow cytometry studies of P815 cells that were incubated with compound 5c at its IC(50) concentration for 24h showed induction of apoptosis in a large percentage of cells. Compounds 5a and 5c were selected by the NCI for an in vivo anticancer hollow-fiber test, and received composite scores of 18 and 22, respectively. These two compounds were subsequently evaluated for in vivo anticancer activity against the growth of a human advanced stage SC UACC-257 melanoma in skid mice. At a dose of 134 mg/kg administered IP, compound 5c gave a T/C value of 40% (for day 51), and the median number of days of doubling tumor growth was 27.7, versus 15.8 for untreated animals. For compound 5a, at 200mg/kg, the T/C was 58% and the median number of days of doubling tumor growth was 20.0 versus 8.7 for untreated animals. At these doses no toxicity or weight loss was observed for either compound. Furthermore, compound 5c was not toxic to murine bone marrow cell growth in culture, at a dose that was toxic for the previously reported seco-CBI (cyclopropylbenzoindoline)-TMI (4).


Assuntos
Antineoplásicos/síntese química , Indóis/síntese química , Pirrolidinonas/síntese química , Animais , Antineoplásicos/farmacologia , Sítios de Ligação , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , DNA/metabolismo , Desenho de Fármacos , Avaliação Pré-Clínica de Medicamentos , Duocarmicinas , Humanos , Indóis/farmacologia , Concentração Inibidora 50 , Melanoma Experimental/tratamento farmacológico , Camundongos , Camundongos SCID , Pirrolidinonas/farmacologia , Relação Estrutura-Atividade , Transplante Heterólogo
8.
Molecules ; 9(3): 125-33, 2004 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-18007417

RESUMO

Analogs of the seco-cyclopyrroloindoline (seco-CPI), the DNA alkylation pharmacophore of CC-1065 and the duocarmycins, can be prepared through a 5-exo-trig radical cyclization of a free radical and a 3-chloro-2-allylic moiety. This manuscript reports an unexpected discovery that, depending on the structure and stability of the free radical, the cyclization process leads to the production of an appreciable amount of seco- cyclopropyltetrahydroquinolines 7a-d along with the seco-cyclopropoyltetra- hydroindoline products (6a-e). For instance, free radical reaction of the bromoallylic chloride 5a produced an equal amount of 6-benzyloxy-N-t-butoxycarbonyl-3- (chloromethyl)furano[e]indoline (6a), and 7-benzyloxy-N-t-butoxycarbonyl-3-chloro- 1,2,3,4-tetrahydrofurano[f]quinoline (7a). Three other examples that produced mixtures of indoline and quinoline products are provided. In only one of the examples reported in this manuscript, the 6-benzyloxy-N-t-butoxycarbonyl-3-(chloromethyl)benzo[e]indoline, was a seco-CBI precursor 6e formed exclusively, consistent with literature precedents.


Assuntos
Antineoplásicos Alquilantes/síntese química , Ciclopropanos/síntese química , Indóis/síntese química , Antineoplásicos Alquilantes/química , Antineoplásicos Alquilantes/farmacologia , Ciclização , Ciclopropanos/química , Ciclopropanos/farmacologia , Duocarmicinas , Humanos , Indóis/química , Indóis/farmacologia , Pirróis/síntese química , Pirróis/química , Pirrolidinonas/síntese química , Pirrolidinonas/química
9.
J Biol Chem ; 277(46): 44576-81, 2002 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-12226100

RESUMO

Nucleotide excision repair (NER) is the primary pathway for the removal of DNA adducts that distort the double helix. In the yeast Saccharomyces cerevisiae the RAD6 epistasis group defines a more poorly characterized set of DNA damage response pathways, believed to be distinct from NER. Here we show that the elimination of the DNA minor groove adducts formed by an important class of anticancer antibiotic (CC-1065 family) requires NER factors in S. cerevisiae. We also demonstrate that the elimination of this class of minor groove adduct from the active MFA2 gene depends upon functional Rad18 and Rad6. This is most clear for the repair of adducts on the transcribed strand, where an absolute requirement for Rad6 and Rad18 was seen. Further experiments revealed that a specific RAD6-RAD18-controlled subpathway, the RAD5 branch, mediates these events. Cells disrupted for rad5 are highly sensitive to this minor groove binding agent, and rad5 cells exhibit an in vivo adduct elimination defect indistinguishable from that seen in rad6 and rad18 cells as well as in NER-defective cells. Our results indicate that the RAD5 subpathway may interact with NER factors during the repair of certain DNA adducts.


Assuntos
Adenosina Trifosfatases , Adutos de DNA , Reparo do DNA , Proteínas Fúngicas/metabolismo , Proteínas de Saccharomyces cerevisiae , Saccharomyces cerevisiae/metabolismo , Dano ao DNA , DNA Helicases , Proteínas de Ligação a DNA/metabolismo , Relação Dose-Resposta a Droga , Ligases/metabolismo , Modelos Químicos , Reação em Cadeia da Polimerase , Transcrição Gênica , Enzimas de Conjugação de Ubiquitina , Raios Ultravioleta
10.
Bioorg Med Chem ; 10(9): 2941-52, 2002 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-12110316

RESUMO

The design, synthesis and biological evaluation of novel seco-iso-cyclopropylfurano[2,3-e]indoline (seco-iso-CFI) and the seco-cyclopropyltetrahydrofurano[2,3-f]quinoline (seco-CFQ) analogues of the duocarmycins are described. These novel analogues (4-7) were designed on the premise that the lone pair of electrons on the furano-oxygen atom could enter into conjugation with the isocyclopropylfurano[e]indolone (iso-CFI) alkylating moiety, formed from the loss of HCl in compounds 4-7. The seco-iso-CFI DNA alkylating pharmacophore was synthesized through a well precedented approach of 5-exo-trig aryl radical cyclization with a vinyl chloride. In our studies, in addition to the formation of the seco-iso-CFI product, an equal amount of an unexpected seco-CFQ product was also generated during the radical cyclization reaction. Like CC-1065 and adozelesin, using Taq DNA polymerase stop and thermal cleavage assays, the seco-iso-CFI compounds (4 and 6) and the seco-CFQ compounds (5 and 7) were shown to preferentially alkylate the adenine-N3 position within the minor groove of long stretches of A residues. A MM2 energy optimized molecular model of a 1:1 complex of compound 6 with DNA reveals that the iso-CFI compound fits snugly within the minor groove. Using a MTT based experiment, the cytotoxicity of compounds 4-7 were determined against the growth of murine leukemia (L1210), mastocytoma (P815) and melanoma (B16) cell lines. The concentrations of compounds required to inhibit the growth of these tumor cells by 50% is in the range of 10(-8)M. These compounds were also tested against a panel of human cancer cells by the National Cancer Institute, demonstrating that the compounds exhibited a high level of activity against selected solid tumors. At a concentration of 0.0084 microM (based on the IC(50) of compound 17 (seco-CBI-TMI) against the growth L1210 cells), while compounds 4 and 17 were toxic against murine bone marrow cells as judged by a colony forming study of freshly isolated murine progenitor hematopoeitic cells, compound 5, a seco-CFQ compound, was significantly less toxic. Flow cytometric analysis of P815 cells that had been incubated for 24h with compounds 4 and 5 at their cytotoxic IC(50) concentrations indicated the induction of apoptosis in a large percentage of cells, thereby suggesting that this might be the mechanism by which the iso-CFI compounds kill cells.


Assuntos
Antineoplásicos Alquilantes/síntese química , Pirróis/química , Animais , Antineoplásicos Alquilantes/farmacologia , Antineoplásicos Alquilantes/toxicidade , Sítios de Ligação , Células da Medula Óssea/efeitos dos fármacos , Ciclo Celular/efeitos dos fármacos , Divisão Celular/efeitos dos fármacos , DNA/metabolismo , Adutos de DNA/síntese química , Adutos de DNA/farmacologia , Desenho de Fármacos , Ensaios de Seleção de Medicamentos Antitumorais , Duocarmicinas , Furanos/química , Furanos/farmacologia , Células-Tronco Hematopoéticas/efeitos dos fármacos , Indóis , Camundongos , Modelos Moleculares , Pirróis/farmacologia , Pirróis/toxicidade , Quinolinas , Relação Estrutura-Atividade
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