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1.
J Equine Vet Sci ; 88: 102939, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32303321

RESUMO

Hereditary equine regional derma asthenia (HERDA), an autosomal-recessive trait, found in Quarter Horses, causes abnormal collagen structure. Owing to current breeding practices, 3.5% of registered quarter horses and 28.3% of the cow horse population are heterozygote carriers. Research demonstrated homozygote horses develop hyperextensible skin susceptible to injury and other abnormal tissues containing high fibrillar collagen content. No research exists determining the effects of the disease in heterozygote carriers. Currently, 30% of cutting sires are HERDA carriers, potentially increasing the number of heterozygous individuals when bred. The objective of the present study is to gauge knowledge of the disease, perception, and concerns of the diseases' impact on horse performance and perceived value and breeding decisions. A Qualtrics link was distributed to horse owners via extension specialists and was available online on equine-related Facebook pages. Overall group means and standard deviations for constructs were reported. A total of 228 responses were collected. Most participants were involved in reining and cutting and 34.6% reported they were very familiar with the disease. Participants (78.5%) reported that HERDA status affects value of a breeding animal. Owners of HERDA carriers (62.5%) noticed no difference in performance or injury compared with noncarriers. Respondents (95.2%) believed that all breeding animals should have HERDA status available. Respondents are attempting to make informed breeding decisions based on HERDA status by pairing carriers with noncarriers; however, it remains to be seen if that is adequate to control the disease. Education regarding breeding practices and its impact on the genetic pool are warranted.


Assuntos
Doenças dos Cavalos , Anormalidades da Pele , Animais , Astenia/veterinária , Homozigoto , Doenças dos Cavalos/genética , Cavalos , Percepção , Anormalidades da Pele/veterinária
2.
J Equine Vet Sci ; 77: 114-120, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-31133303

RESUMO

Five experiments were performed to test the hypothesis that α-melanocyte-stimulating hormone (MSH) is secreted in response to various stressors in horses similar to prolactin, growth hormone, and adrenocorticotropin (ACTH). There was considerable variation in resting concentrations of MSH and in the degree of stimulation in responders; thus all data sets were tested for heterogeneity of variance and corrected for as needed before analysis. In experiment 1, 12 mares were used in a switchback design to test the effect of a 2-minute exercise bout on MSH secretion. Plasma MSH concentrations were constant when mares were not exercised but increased (P < .05) immediately (2 minutes) after exercise and were still elevated 5 minutes later. In experiment 2, six mares were twitched for 2 minutes and six mares were not twitched. Twitching stimulated (P < .05) both MSH and ACTH relative to controls. Experiments 3, 4, and 5 tested the acute effects of intravenous injection of epinephrine at 5 µg/kg of body weight, intravenous injection of 100 µg substance P, and intramuscular injection of 10 mg prostaglandin-F2α in mares compared to controls (6, 5, and 6 mares per treatment group, respectively). Concentrations of MSH increased (P ≤ .05) after treatment in all three experiments. Plasma concentrations of ACTH also increased (P < .01) after administration of epinephrine and prostaglandin-F2α in experiments 3 and 5; plasma ACTH was not measured in experiment 1 or 4 because we have previously reported that exercise and substance P stimulate plasma ACTH concentrations. As hypothesized, MSH is secreted in response to various stimuli similar to that observed previously for prolactin, growth hormone, and ACTH.


Assuntos
Epinefrina , Substância P , Hormônio Adrenocorticotrópico , Animais , Feminino , Hormônio do Crescimento , Cavalos , Hormônios Estimuladores de Melanócitos
3.
Eur Radiol ; 27(11): 4797-4803, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28526892

RESUMO

OBJECTIVES: To evaluate breast biopsy marker migration in stereotactic core needle biopsy procedures and identify contributing factors. METHODS: This retrospective study analyzed 268 stereotactic biopsy markers placed in 263 consecutive patients undergoing stereotactic biopsies using 9G vacuum-assisted devices from August 2010-July 2013. Mammograms were reviewed and factors contributing to marker migration were evaluated. Basic descriptive statistics were calculated and comparisons were performed based on radiographically-confirmed marker migration. RESULTS: Of the 268 placed stereotactic biopsy markers, 35 (13.1%) migrated ≥1 cm from their biopsy cavity. Range: 1-6 cm; mean (± SD): 2.35 ± 1.22 cm. Of the 35 migrated biopsy markers, 9 (25.7%) migrated ≥3.5 cm. Patient age, biopsy pathology, number of cores, and left versus right breast were not associated with migration status (P> 0.10). Global fatty breast density (P= 0.025) and biopsy in the inner region of breast (P = 0.031) were associated with marker migration. Superior biopsy approach (P= 0.025), locally heterogeneous breast density, and t-shaped biopsy markers (P= 0.035) were significant for no marker migration. CONCLUSIONS: Multiple factors were found to influence marker migration. An overall migration rate of 13% supports endeavors of research groups actively developing new biopsy marker designs for improved resistance to migration. KEY POINTS: • Breast biopsy marker migration is documented in 13% of 268 procedures. • Marker migration is affected by physical, biological, and pathological factors. • Breast density, marker shape, needle approach etc. affect migration. • Study demonstrates marker migration prevalence; marker design improvements are needed.


Assuntos
Biópsia com Agulha de Grande Calibre/instrumentação , Neoplasias da Mama/diagnóstico por imagem , Mama/diagnóstico por imagem , Migração de Corpo Estranho/diagnóstico por imagem , Mamografia , Biópsia com Agulha de Grande Calibre/métodos , Mama/patologia , Densidade da Mama , Neoplasias da Mama/patologia , Feminino , Humanos , Imageamento Tridimensional , Pessoa de Meia-Idade , Estudos Retrospectivos
4.
Biol Reprod ; 96(3): 617-634, 2017 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-28339619

RESUMO

Mechanisms governing the timing of puberty in pigs are poorly understood. A genome-wide association study for age at first estrus in pigs identified candidate genes including neuropeptide FF receptor 2 (NPFFR2), which is a putative receptor for RFamide-related peptides (RFRP). RFRP has been shown to negatively regulate secretion of reproductive hormones from hypothalamic and pituitary tissue of pigs in culture. Here, the porcine NPFFR2 gene was further screened and four potentially functional variants were identified to be associated with age at first estrus in pigs (1,288 gilts). The RFRP neurons in the porcine hypothalamus were localized in the paraventricular and dorsomedial nuclei with RFRP fibers in the lateral hypothalamic area. There were marked changes in expression of NPFF receptors in the anterior pituitary gland and hypothalamus of gilts beginning with the peripubertal period. The hypothesis that NPFF receptor function is related to secretion of luteinizing hormone (LH) in gilts was tested with various NPFF receptor ligands. The NPFF receptor antagonist RF9 stimulated a pulse-like release of LH in prepubertal gilts. The putative NPFF receptor agonist RFRP3 modestly suppressed LH pulses in ovariectomized (OVX) prepubertal gilts. A porcine-specific RFRP2 failed to have an effect on LH secretion in OVX prepubertal gilts despite its high degree of homology to avian gonadotropin-inhibitory hormone. Results indicate that an RFRP system is present in the pig and that NPFFR2 is important for pubertal onset in gilts. It is not clear if this regulation involves major control of LH secretion or another unknown mechanism.


Assuntos
Hipotálamo/metabolismo , Hormônio Luteinizante/metabolismo , Neuropeptídeos/metabolismo , Adeno-Hipófise/metabolismo , Receptores de Neuropeptídeos/metabolismo , Maturidade Sexual , Adamantano/análogos & derivados , Animais , Dipeptídeos , Feminino , Suínos
5.
Cogn Behav Pract ; 20(1): 23-32, 2013 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-24043922

RESUMO

In this article, we consider the use of Mindfulness-Based Stress Reduction (MBSR) (Kabat-Zinn, 1991) as a community-based intervention to reduce health disparities for low-income, predominantly African American women with a history of intimate partner violence (IPV) and posttraumatic stress disorder (PTSD). This article presents our rationale for using MBSR as an intervention with this population, the details of its implementation, and a discussion of the feasibility and acceptability of the intervention based on participants' feedback and our observations. We conclude that the use of MBSR programs for low-income, predominantly African American women with PTSD and a history of IPV is both feasible (of initial interest to and completed by most participants) and acceptable (congruent with and relevant to their needs). Replication with larger samples and examination of mechanisms is warranted by these findings.

6.
Psychiatry Res ; 210(2): 618-25, 2013 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-23850437

RESUMO

Past trauma and stressful events, especially in childhood and adolescence, are common among individuals with serious mental illnesses like schizophrenia. Traumatic experiences are thought to be a socio-environmental risk factor not only for poorer outcomes, but also potentially for the onset of these disorders. Because improved measurement tools are needed, we developed and studied, among 205 first-episode psychosis patients, the factor structure, internal consistency reliability, and initial validity of the Trauma Experiences Checklist (TEC), our measure of trauma and stressful events during childhood/adolescence. We assessed validity of subscales using correlations with Childhood Trauma Questionnaire-Short Form, Parental Harsh Discipline, Violence Exposure, and TEC-Informant Version scores. Exploratory factor analysis resulted in two internally consistent subscales (Cronbach's α=0.79 and 0.80, respectively), interpersonal abuse and family stress, and violence, death, and legal involvement. Scores from the former subscale were substantially associated with CTQ-SF physical, emotional, and sexual abuse (r=0.42-0.57, all p<0.001) and Violence Exposure (r=0.49, p<0.001). On the other hand, violence, death, and legal involvement scores were most highly correlated with Violence Exposure (r=0.49, p<0.001), and not with most CTQ-SF subscales. The TEC is a potentially useful tool in assessing diverse traumatic life events across various social contexts during childhood and adolescence.


Assuntos
Maus-Tratos Infantis/psicologia , Acontecimentos que Mudam a Vida , Transtornos Psicóticos/diagnóstico , Transtornos de Estresse Pós-Traumáticos/psicologia , Inquéritos e Questionários/normas , Adolescente , Adulto , Lista de Checagem , Criança , Análise Fatorial , Feminino , Humanos , Masculino , Pais , Escalas de Graduação Psiquiátrica , Psicometria/instrumentação , Psicometria/estatística & dados numéricos , Transtornos Psicóticos/psicologia , Reprodutibilidade dos Testes , Fatores de Risco , Meio Social , Transtornos de Estresse Pós-Traumáticos/diagnóstico
7.
Schizophr Res ; 148(1-3): 93-8, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23746486

RESUMO

OBJECTIVE: Longer duration of untreated psychosis (DUP) is associated with poorer early-course and long-term outcomes, and is a target of early detection and intervention efforts. Given the paucity of research on childhood and adolescent stressors (e.g., maltreatment and neighborhood disorder) as potential predictors of DUP, limited research on premorbid substance use as a determinant of DUP, and inconclusive findings on the association between DUP and neurocognition, we conducted three sets of analyses to address these issues. Mode of onset of psychosis was also considered, given its established role as an illness-level correlate of DUP. METHODS: We rigorously assessed DUP and other pertinent variables in 180 predominantly African American, low-income, and socially disadvantaged first-episode psychosis patients hospitalized in five psychiatric units. RESULTS: Mode of onset of psychosis, prior incarceration, and the level of childhood/adolescent maltreatment were all significant independent predictors of DUP. Regarding premorbid substance use, having ever used cannabis and the amount of premorbid alcohol use were significantly associated with DUP. None of the seven neurocognitive domains assessed were even modestly, or clinically meaningfully, associated with DUP. CONCLUSIONS: These and other findings on DUP may be informative for early detection and intervention services. For example, such services might benefit from special outreach to criminal justice settings and disadvantaged neighborhoods, and to young people likely to have a history of childhood/adolescent maltreatment and gradually developing psychotic symptoms.


Assuntos
Maus-Tratos Infantis/psicologia , Demografia , Pobreza/psicologia , Transtornos Psicóticos , Transtornos Relacionados ao Uso de Substâncias/psicologia , Adolescente , Adulto , Negro ou Afro-Americano , Idade de Início , Criança , Diagnóstico Precoce , Feminino , Humanos , Masculino , Valor Preditivo dos Testes , Escalas de Graduação Psiquiátrica , Transtornos Psicóticos/diagnóstico , Transtornos Psicóticos/epidemiologia , Transtornos Psicóticos/psicologia , Estatística como Assunto , Transtornos Relacionados ao Uso de Substâncias/epidemiologia , Inquéritos e Questionários , Adulto Jovem
8.
Reproduction ; 135(6): 879-87, 2008 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-18339687

RESUMO

It is well established that kisspeptin signaling is necessary for the onset of puberty in laboratory animals. However, the role that kisspeptin may have in regulating puberty in large domestic animals is unknown. We tested the hypothesis that either central or peripheral infusion of kisspeptin would stimulate gonadotropin and GH secretion in prepubertal gilts. In experiment 1, prepubertal gilts were fitted with i.c.v. cannula and indwelling jugular catheters. Animals were randomly assigned to receive 0, 10, or 100 microg kisspeptin in saline. In experiment 2, prepubertal gilts, fitted with indwelling jugular catheters, randomly received 0, 1, 2.5, or 5 mg kisspeptin in saline intravenously. Serial blood samples were collected every 15 min for 3 h before and 5 h after infusions, and serum concentrations of LH, FSH, and GH were determined. Mean concentrations of LH and FSH remained at basal levels for control animals but were increased (P<0.001) for animals receiving i.c.v. infusion of kisspeptin. Area under the LH and FSH curves following i.c.v. infusion of kisspeptin increased (P<0.001) in a dose-dependent manner. Concentrations of GH were unaffected by i.c.v. treatment. Peripheral administration of kisspeptin increased (P<0.05) serum concentrations of LH but not FSH or GH. Thus, kisspeptin can activate gonadotropic but not somatotropic hormone secretion in prepubertal gilts. The present data support the concept that kisspeptin plays a role in the mechanism involved in initiating puberty in swine.


Assuntos
Gonadotropinas Hipofisárias/metabolismo , Hormônio do Crescimento/metabolismo , Adeno-Hipófise/metabolismo , Maturidade Sexual/efeitos dos fármacos , Suínos/fisiologia , Proteínas Supressoras de Tumor/administração & dosagem , Animais , Cateterismo , Veias Cerebrais , Relação Dose-Resposta a Droga , Esquema de Medicação , Feminino , Hormônio Foliculoestimulante/sangue , Hormônio Foliculoestimulante/metabolismo , Hormônio Liberador de Gonadotropina/farmacologia , Gonadotropinas Hipofisárias/sangue , Hormônio do Crescimento/sangue , Infusões Intravenosas , Veias Jugulares , Kisspeptinas , Hormônio Luteinizante/sangue , Hormônio Luteinizante/metabolismo , Adeno-Hipófise/efeitos dos fármacos , Radioimunoensaio , Distribuição Aleatória , Proteínas Supressoras de Tumor/farmacologia
9.
Genetics ; 157(3): 1205-15, 2001 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-11238405

RESUMO

The Schizosaccharomyces pombe fbp1 gene, which encodes fructose-1,6-bis-phosphatase, is transcriptionally repressed by glucose through the activation of the cAMP-dependent protein kinase A (PKA) and transcriptionally activated by glucose starvation through the activation of a mitogen-activated protein kinase (MAPK). To identify transcriptional regulators acting downstream from or in parallel to PKA, we screened an adh-driven cDNA plasmid library for genes that increase fbp1 transcription in a strain with elevated PKA activity. Two such clones express amino-terminally truncated forms of the S. pombe tup12 protein that resembles the Saccharomyces cerevisiae Tup1p global corepressor. These clones appear to act as dominant negative alleles. Deletion of both tup12 and the closely related tup11 gene causes a 100-fold increase in fbp1-lacZ expression, indicating that tup11 and tup12 are redundant negative regulators of fbp1 transcription. In strains lacking tup11 and tup12, the atf1-pcr1 transcriptional activator continues to play a central role in fbp1-lacZ expression; however, spc1 MAPK phosphorylation of atf1 is no longer essential for its activation. We discuss possible models for the role of tup11- and tup12-mediated repression with respect to signaling from the MAPK and PKA pathways. A third clone identified in our screen expresses the php5 protein subunit of the CCAAT-binding factor (CBF). Deletion of php5 reduces fbp1 expression under both repressed and derepressed conditions. The CBF appears to act in parallel to atf1-pcr1, although it is unclear whether or not CBF activity is regulated by PKA.


Assuntos
Fator de Ligação a CCAAT/genética , Frutose-Bifosfatase/genética , Proteínas Fúngicas/genética , Regulação Fúngica da Expressão Gênica , Proteínas Nucleares , Proteínas Repressoras , Proteínas de Saccharomyces cerevisiae , Schizosaccharomyces/genética , Transcrição Gênica , Sequência de Aminoácidos , Clonagem Molecular , Proteínas Quinases Dependentes de AMP Cíclico/metabolismo , DNA Complementar/metabolismo , Deleção de Genes , Biblioteca Gênica , Genótipo , Sistema de Sinalização das MAP Quinases , Dados de Sequência Molecular , Mutação , Fenótipo , Fosforilação , Plasmídeos/genética , Regiões Promotoras Genéticas , Homologia de Sequência de Aminoácidos , Transdução de Sinais , Temperatura , Ativação Transcricional , beta-Galactosidase/metabolismo
10.
Mol Cell Biol ; 20(17): 6426-34, 2000 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-10938120

RESUMO

A significant challenge to our understanding of eukaryotic transcriptional regulation is to determine how multiple signal transduction pathways converge on a single promoter to regulate transcription in divergent fashions. To study this, we have investigated the transcriptional regulation of the Schizosaccharomyces pombe fbp1 gene that is repressed by a cyclic AMP (cAMP)-dependent protein kinase A (PKA) pathway and is activated by a stress-activated mitogen-activated protein kinase (MAPK) pathway. In this study, we identified and characterized two cis-acting elements in the fbp1 promoter required for activation of fbp1 transcription. Upstream activation site 1 (UAS1), located approximately 900 bp from the transcriptional start site, resembles a cAMP response element (CRE) that is the binding site for the atf1-pcr1 heterodimeric transcriptional activator. Binding of this activator to UAS1 is positively regulated by the MAPK pathway and negatively regulated by PKA. UAS2, located approximately 250 bp from the transcriptional start site, resembles a Saccharomyces cerevisiae stress response element. UAS2 is bound by transcriptional activators and repressors regulated by both the PKA and MAPK pathways, although atf1 itself is not present in these complexes. Transcriptional regulation of fbp1 promoter constructs containing only UAS1 or UAS2 confirms that the PKA and MAPK regulation is targeted to both sites. We conclude that the PKA and MAPK signal transduction pathways regulate fbp1 transcription at UAS1 and UAS2, but that the antagonistic interactions between these pathways involve different mechanisms at each site.


Assuntos
Proteínas Quinases Dependentes de AMP Cíclico/metabolismo , Proteínas de Domínio MADS , Sistema de Sinalização das MAP Quinases , Proteínas de Plantas/genética , Proteínas de Schizosaccharomyces pombe , Schizosaccharomyces/genética , Fatores de Transcrição/genética , Transcrição Gênica , Fator 1 Ativador da Transcrição , Fatores Ativadores da Transcrição , Sequência de Aminoácidos , Proteínas de Ligação a DNA/metabolismo , Deleção de Genes , Regulação da Expressão Gênica , Modelos Genéticos , Dados de Sequência Molecular , Mutagênese Sítio-Dirigida , Regiões Promotoras Genéticas , Homologia de Sequência de Aminoácidos , Fatores de Transcrição/metabolismo , Ativação Transcricional , beta-Galactosidase/metabolismo
11.
J Mol Biol ; 291(3): 549-60, 1999 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-10448036

RESUMO

Transcription factor IIIA of Xenopuslaevis serves a dual function during oogenesis and early development: this zinc finger protein binds to the internal promoter element of the 5 S ribosomal RNA genes and acts as a positive transcription factor; additionally, the protein functions in 5 S RNA storage. The central four zinc fingers (zf4-7) of the nine-finger protein have been shown to bind 5 S rRNA with comparable or higher affinity than the full-length protein. The role of finger seven in binding affinity has been examined by deletion analysis. A zf4-6 protein binds 5 S RNA with about a sevenfold reduction in binding affinity, compared to zf4-7. The effect of non-specific competitor DNA on binding affinities of the zinc finger peptides was examined and found to have a significant effect on the measured affinities of these peptides for full-length and truncated versions of 5 S RNA. The interaction of zf4-6 with full-length 5 S RNA was far more sensitive to non-specific competitor concentration than was the zf4-7:5 S RNA interaction, suggesting that finger seven contributes to both affinity and specificity in this protein:RNA interaction. In order to map zinc finger binding sites on the 5 S RNA molecule, we generated truncated versions of the RNA and tested these molecules for their binding affinities with zf4-7 and zf4-6. Previous studies showed that a 75 nucleotide long RNA, comprising loop A, helix II, helix V, region E and helix IV, bound zf4-7 with high affinity. Selection and amplification binding assays (selex) have now been used to generate smaller high-affinity binding RNAs. We find that a 55 nucleotide long RNA, comprising loop A, helix V, region E and helix IV, but lacking helix II, retains high affinity for zf4-6. These data are consistent with the proposal that fingers 4-6 bind this central core of 5 S RNA and that finger seven binds the helix II region.


Assuntos
Proteínas de Ligação a DNA/química , Proteínas de Ligação a DNA/metabolismo , RNA Ribossômico 5S/química , RNA Ribossômico 5S/metabolismo , Fatores de Transcrição/química , Fatores de Transcrição/metabolismo , Animais , Sequência de Bases , Sítios de Ligação/genética , Ligação Competitiva , Primers do DNA/genética , Proteínas de Ligação a DNA/genética , Feminino , Técnicas In Vitro , Cinética , Dados de Sequência Molecular , Conformação de Ácido Nucleico , Oócitos/metabolismo , RNA Ribossômico 5S/genética , Fator de Transcrição TFIIIA , Fatores de Transcrição/genética , Xenopus laevis , Dedos de Zinco/genética
12.
Nature ; 387(6629): 202-5, 1997 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-9144294

RESUMO

Small molecules that target specific DNA sequences have the potential to control gene expression. Ligands designed for therapeutic application must bind any predetermined DNA sequence with high affinity and permeate living cells. Synthetic polyamides containing N-methylimidazole and N-methylpyrrole amino acids have an affinity and specificity for DNA comparable to naturally occurring DNA-binding proteins. We report here that an eight-ring polyamide targeted to a specific region of the transcription factor TFIIIA binding site interferes with 5S RNA gene expression in Xenopus kidney cells. Our results indicate that pyrrole-imidazole polyamides are cell-permeable and can inhibit the transcription of specific genes.


Assuntos
DNA/metabolismo , Regulação da Expressão Gênica/efeitos dos fármacos , Nylons/farmacologia , Animais , Sítios de Ligação , Linhagem Celular , Pegada de DNA , Proteínas de Ligação a DNA/metabolismo , Imidazóis/análise , Estrutura Molecular , Nylons/química , Nylons/metabolismo , Pirróis/análise , RNA Ribossômico 5S/genética , RNA de Transferência/genética , Fator de Transcrição TFIIIA , Fatores de Transcrição/metabolismo , Transcrição Gênica/efeitos dos fármacos , Xenopus , Dedos de Zinco
13.
J Mol Biol ; 274(4): 439-45, 1997 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-9417925

RESUMO

The gene-specific transcription factor IIIA (TFIIIA) binds to the internal promoter element of the 5 S rRNA gene through nine zinc fingers which make specific DNA contacts. Seven of the nine TFIIIA zinc fingers participate in major groove DNA contacts while two fingers, 4 and 6, have been proposed to bind in or across the minor groove. Pyrrole-imidazole polyamides are minor groove binding ligands that recognize predetermined DNA sequences with affinity and specificity comparable to natural DNA-binding proteins. We have examined the DNA binding activity of nine finger TFIIIA and shorter recombinant analogs in the presence of polyamides that bind six base-pair sequences (Kd = 0.03 to 1.7 nM) in the minor groove of the binding site for zinc finger 4. DNase I footprint titrations demonstrate that the polyamides and a recombinant protein containing the three amino-terminal zinc fingers of TFIIIA (zf1-3) co-occupy the TFIIIA binding site, in agreement with the known location of zf1-3 in the major groove. In contrast, the polyamides block the specific interaction of TFIIIA or zf1-4 with the 5 S RNA gene, supporting a model for minor groove occupancy by zinc finger 4. Minor groove binding polyamides targeted to specific DNA sequences may provide a novel chemical approach to probing multidomain protein-DNA interactions.


Assuntos
Proteínas de Ligação a DNA/química , Proteínas de Ligação a DNA/metabolismo , Fatores de Transcrição/química , Fatores de Transcrição/metabolismo , Dedos de Zinco , Sítios de Ligação , DNA/metabolismo , Desoxirribonuclease I/metabolismo , Guanina/química , Guanina/metabolismo , Nylons/química , Nylons/metabolismo , Conformação Proteica , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Fator de Transcrição TFIIIA
14.
J Inorg Biochem ; 49(2): 149-56, 1993 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-8455019

RESUMO

Several monomeric cyclometallated palladium complexes have been prepared by bridge opening reactions of their corresponding dimeric precursors with various amines. The complexes were characterized by elemental analyses and proton NMR spectroscopy. The general formula for the complexes can be given as Pd(N-C)LX where (N-C) is an aromatic or aliphatic amine coordinated as a chelating ligand through the amine and a formal cyclometallated Pd-C bond; L = amine, X = chloride or acetate. A unique complex based on the cyclopalladation of 2-phenyl phenanthroline was also prepared directly. The series of complexes was screened for cytotoxicity against a panel of seven human tumor cell lines. All complexes were found to be cytotoxic (IC50) at micrograms/ml concentrations, while two complexes also displayed some differential cytotoxicity.


Assuntos
Antineoplásicos/síntese química , Paládio/química , Antineoplásicos/química , Antineoplásicos/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Neoplasias do Colo/tratamento farmacológico , Neoplasias Colorretais/tratamento farmacológico , Ciclização , Humanos , Espectroscopia de Ressonância Magnética , Metais , Estrutura Molecular , Paládio/uso terapêutico , Relação Estrutura-Atividade , Células Tumorais Cultivadas , Neoplasias da Bexiga Urinária/tratamento farmacológico
15.
Clin Phys Physiol Meas ; 12(3): 219-26, 1991 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-1934910

RESUMO

An optical method to measure directly small displacements of the patella has been developed. Light from a helium-neon laser was reflected from a plane mirror taped to the skin over the patella to a glass plate which generated a set of fringes by interference of light reflected from the front and rear surfaces of the plate. The movement of the fringe system was detected using a photodiode. The optical measurements of displacement were compared with those deduced from an accelerometer attached to the same joint. The method was found to be capable of detecting patellar displacements in the range from 20 microns to 180 microns.


Assuntos
Fêmur/fisiologia , Articulação do Joelho/fisiologia , Patela/fisiologia , Fêmur/fisiopatologia , Humanos , Articulação do Joelho/fisiopatologia , Movimento , Óptica e Fotônica , Patela/fisiopatologia , Valores de Referência , Fenômenos Fisiológicos da Pele , Sono , Vibração
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