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1.
J Chem Phys ; 136(11): 114313, 2012 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-22443770

RESUMO

We report high resolution measurements of 372 NaCs 5(3)Π(0)(v, J) ro-vibrational level energies in the range 0 ≤ v ≤ 22. The data have been used to construct NaCs 5(3)Π(0) potential energy curves using the Rydberg-Klein-Rees and inverted perturbation approximation methods. Bound-free 5(3)Π(0)(v, J) → 1(a)(3)Σ(+) emission has also been measured, and is used to determine the repulsive wall of the 1(a)(3)Σ(+) state and the 5(3)Π(0) → 1(a)(3)Σ(+) relative transition dipole moment function. Hyperfine structure in the 5(3)Π(0) state has not been observed in this experiment. This null result is explained using a simple vector coupling model.

2.
Br J Cancer ; 106(1): 45-52, 2012 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-22075942

RESUMO

BACKGROUND: Cervical screening identifies many women with low-grade abnormalities. In vitro and in vivo studies have shown that diindolylmethane (DIM) could potentially halt (cervical) carcinogenesis. We report on a randomised controlled trial of the effect of DIM in women with low-grade cervical cytological abnormalities. METHODS: We conducted a pragmatic double-blind, randomised controlled trial of 150 mg DIM (from BioResponse DIM) or placebo daily for 6 months in women with newly diagnosed, low-grade cytological abnormalities. Randomisation was in the ratio 2 (DIM) to 1 (placebo). All women were invited for colposcopy at 6 months with biopsy of any abnormality. RESULTS: Of the 551 randomised women available for analysis, 9% on DIM and 12% on placebo had cervical intraepithelial neoplasia-2 (CIN2) or worse after 6-month supplementation (risk ratio (RR) 0.7 (95% confidence interval (CI): 0.4-1.2)), whereas 4.6% and 5.1%, respectively, had CIN3 or worse (RR 0.9 (95% CI: 0.4-2.0)). A total of 27.3% of women on DIM and 34.3% on placebo had no sign of disease (negative cytology, colposcopy and human papilloma virus (HPV) tests) at 6 months (RR 0.8 (95% CI: 0.6-1.0)). Of those HPV-positive at baseline, 69% (114 out of 166) of the DIM group were positive at 6 months compared with 61% (43 out of 71) of the placebo group: RR 1.1 (95% CI: 0.9-1.4). Diindolylmethane supplementation was well tolerated. CONCLUSION: The results suggest that short-term DIM supplementation (150 mg day(-1)) is well tolerated, but is unlikely to have an effect on cytology or HPV infection. Uncertainty remains regarding its effect on CIN2+.


Assuntos
Anticarcinógenos/uso terapêutico , Indóis/uso terapêutico , Displasia do Colo do Útero/tratamento farmacológico , Adulto , Alphapapillomavirus/isolamento & purificação , Anticarcinógenos/efeitos adversos , Anticarcinógenos/farmacologia , Apoptose/efeitos dos fármacos , Método Duplo-Cego , Feminino , Humanos , Indóis/efeitos adversos , Indóis/farmacologia , Pessoa de Meia-Idade , Placebos , Neoplasias do Colo do Útero/prevenção & controle , Displasia do Colo do Útero/virologia
3.
J Chem Phys ; 134(17): 174301, 2011 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-21548681

RESUMO

Collisional satellite lines with |ΔJ| ≤ 58 have been identified in recent polarization spectroscopy V-type optical-optical double resonance (OODR) excitation spectra of the Rb(2) molecule [H. Salami et al., Phys. Rev. A 80, 022515 (2009)]. Observation of these satellite lines clearly requires a transfer of population from the rotational level directly excited by the pump laser to a neighboring level in a collision of the molecule with an atomic perturber. However to be observed in polarization spectroscopy, the collision must also partially preserve the angular momentum orientation, which is at least somewhat surprising given the extremely large values of ΔJ that were observed. In the present work, we used the two-step OODR fluorescence and polarization spectroscopy techniques to obtain quantitative information on the transfer of population and orientation in rotationally inelastic collisions of the NaK molecules prepared in the 2(A)(1)Σ(+)(v' = 16, J' = 30) rovibrational level with argon and potassium perturbers. A rate equation model was used to study the intensities of these satellite lines as a function of argon pressure and heat pipe oven temperature, in order to separate the collisional effects of argon and potassium atoms. Using a fit of this rate equation model to the data, we found that collisions of NaK molecules with potassium atoms are more likely to transfer population and destroy orientation than collisions with argon atoms. Collisions with argon atoms show a strong propensity for population transfer with ΔJ = even. Conversely, collisions with potassium atoms do not show this ΔJ = even propensity, but do show a propensity for ΔJ = positive compared to ΔJ = negative, for this particular initial state. The density matrix equations of motion have also been solved numerically in order to test the approximations used in the rate equation model and to calculate fluorescence and polarization spectroscopy line shapes. In addition, we have measured rate coefficients for broadening of NaK 3(1)Π â† 2(A)(1)Σ(+)spectral lines due to collisions with argon and potassium atoms. Additional broadening, due to velocity changes occurring in rotationally inelastic collisions, has also been observed.

4.
J Biomol Screen ; 6(5): 275-90, 2001 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11689128

RESUMO

This paper describes, for the first time, a true ultra-high throughput screen (uHTS) based upon fluorescence anisotropy and performed entirely in 1536-well assay plates. The assay is based upon binding and displacement of a BODIPY-FL-labeled antibiotic to a specific binding site on 70S ribosomes from Escherichia coli (Kd approximately 15 nM). The screen was performed at uHTS rates (i.e., >100,000 assay wells/24 h) using entirely commercially available equipment. In order to examine the reproducibility of detection of test compound effects, assays were performed in duplicate. Both overall assay statistics and reproducibility for individual compound results were excellent, at least equivalent to conventional HTS assays. Interference artifacts occurred mainly as a result of autofluorescence from test compounds. Well-level quality control procedures were developed to detect, eliminate, or even correct for such effects. Moreover, development of a brighter, longer wavelength probe (based upon Cy3B) markedly reduced such interferences. Overall, the data demonstrate that fluorescence anisotropy-based uHTS is now a practical reality.


Assuntos
Polarização de Fluorescência/métodos , Controle de Qualidade , Antibacterianos/metabolismo , Sítios de Ligação , Compostos de Boro , Escherichia coli/ultraestrutura , Corantes Fluorescentes , Reprodutibilidade dos Testes , Ribossomos/metabolismo
6.
Dev Psychopathol ; 12(4): 695-712, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-11202040

RESUMO

This article provides a targeted review of the scientific literature on the effects of experience on early brain and behavioral development and later outcome as it pertains to risk for some forms of child psychopathology. It is argued that ample evidence exists indicating that the prenatal and early postnatal years likely represent a sensitive period with respect to the effects of stress on the developing nervous system and behavioral outcome, and with respect to the long-term beneficial effects of early interventions on brain and behavioral development for some genetically based disorders, such as phenylketonuria and autism. Moreover, evidence suggests that parental mental health during the first years of life has a significant influence on early brain activity and behavior, and long-term behavioral outcome. It is concluded that, although prevention and early intervention efforts should not exclusively focus on the earliest years of development, such efforts should begin during this period. By directing such efforts toward promoting optimal prenatal and infant-toddler development, the long-term negative consequences of factors that have their greatest influences during early development and which set the stage for future development can be minimized or avoided entirely. Several recommendations for public policy and future research pertaining to the effects of early experience on child outcome are offered.


Assuntos
Encéfalo/fisiologia , Comportamento Infantil/psicologia , Desenvolvimento Infantil/fisiologia , Política Pública , Fatores Etários , Pré-Escolar , Humanos , Lactente , Comportamento Materno/psicologia , Estresse Psicológico/psicologia
7.
Biol Psychiatry ; 46(4): 577-80, 1999 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-10459410

RESUMO

BACKGROUND: Women are overrepresented in samples of patients with rapid cycling bipolar disorder (RCBD). To explore whether menstrually related mood changes might account for this gender difference, we studied the relationship between menstrual cycle phase and mood in a sample of premenopausal women with rapid cycling bipolar disorder (RCBD). METHODS: Twenty-five women with RCBD completed daily self-rating forms indicating their mood and days of menstruation for a minimum of three months. The data were analyzed for each individual and for the group as a whole, categorically (depression, euthymia, and hypomania) and ordinally (0-100, with 0 being "most depressed ever felt" and 100 being "most manic"), with and without normalization of the menstrual cycle to a 28-day cycle. RESULTS: None of the group analyses showed a significant effect of menstrual cycle on mood. Although some women did exhibit significant relationships between menstrual cycle phase and categorical mood state, there was no consistent pattern to the relationship. CONCLUSIONS: There was no systematic relationship between menstrual cycle and mood in a sample of women with RCBD.


Assuntos
Afeto , Transtorno Bipolar/fisiopatologia , Transtorno Bipolar/psicologia , Ciclo Menstrual/psicologia , Adulto , Distribuição de Qui-Quadrado , Feminino , Humanos , Autoavaliação (Psicologia)
8.
Psychiatry Res ; 86(1): 1-8, 1999 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-10359478

RESUMO

Disruptions in the sleep-wake cycle frequently characterize affective illness and have led to a number of theories linking sleep-wake and/or circadian rhythm disturbance to affective illness. Recently, researchers have expanded these chronobiological theories to include the role of lifestyle regularity, or daily social rhythms. In this study, the Social Rhythm Metric (SRM) was used to explore the relationship between social rhythms and mood in patients with rapid cycling bipolar disorder and to compare the social rhythms of patients with those of healthy control subjects. Patients' SRM scores and activity level indices were significantly lower than those of control subjects. In addition, the timing of five, mostly morning, activities was phase delayed in patients compared to control subjects. Patients also demonstrated a phase delay in the timing of morning activities during depression compared to hypomania or euthymia. The phase changes in the timing of morning activities are consistent with other data implicating morning zeitgebers in the pathophysiology of rapid cycling bipolar disorder.


Assuntos
Transtorno Bipolar/diagnóstico , Ajustamento Social , Adulto , Transtorno Bipolar/psicologia , Ritmo Circadiano/fisiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Escalas de Graduação Psiquiátrica , Transtornos Psicomotores/etiologia , Índice de Gravidade de Doença , Transtornos do Sono-Vigília/etiologia , Vigília
9.
Bioorg Med Chem Lett ; 9(3): 443-8, 1999 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-10091699

RESUMO

Cinnamyl derivatives of thieno[2,3-d]oxazinones are mechanism-based inhibitors of the HSV-2, VZV and CMV herpes proteases which demonstrate nanomolar potency. Compounds 5 and 28 inhibit protease processing in HSV-2 infected cells with a selectivity index of at least 30.


Assuntos
Antivirais/farmacologia , Herpesviridae/enzimologia , Oxazinas/farmacologia , Inibidores de Proteases/farmacologia , Antivirais/química , Linhagem Celular , Oxazinas/química , Inibidores de Proteases/química
10.
J Biomol Screen ; 4(6): 335-354, 1999.
Artigo em Inglês | MEDLINE | ID: mdl-10838431

RESUMO

Fluorescence assay technologies used for miniaturized high throughput screening are broadly divided into two classes. Macroscopic fluorescence techniques (encompassing conventional fluorescence intensity, anisotropy [also often referred to as fluorescence polarization] and energy transfer) monitor the assay volume- and time-averaged fluorescence output from the ensemble of emitting fluorophores. In contrast, single-molecule detection (SMD) techniques and related approaches, such as fluorescence correlation spectroscopy (FCS), stochastically sample the fluorescence properties of individual constituent molecules and only then average many such detection events to define the properties of the assay system as a whole. Analysis of single molecular events is accomplished using confocal optics with an illumination/detection volume of approximately 1 fl (10(-15) L) such that the signal is insensitive to miniaturization of HTS assays to 1 µl or below. In this report we demonstrate the general applicability of one SMD technique (FCS) to assay configuration for target classes typically encountered in HTS and confirm the equivalence of the rate/equilibrium constants determined by FCS and by macroscopic techniques. Advantages and limitations of the current FCS technology, as applied here, and potential solutions, particularly involving alternative SMD detection techniques, are also discussed.

11.
Avian Pathol ; 28(5): 501-11, 1999 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26911606

RESUMO

The Newcastle disease virus isolated from healthy turkeys in outbreak GB 97/6 was used to challenge 4-week-old turkeys and chickens, which were either not vaccinated or had received a single dose of Hitchner B1 live vaccine 14 days earlier, by one of the intramuscular, intranasal or contact routes. Similar experiments were done in 38-day-old turkeys and chickens using virus isolated from severely sick chickens in outbreak GB 97/1. All vaccinated chickens showed low but measurable immune responses 14 days after vaccination, but only three of the turkeys had detectable antibodies. No vaccinated turkey or chicken showed any clinical sign after challenge with either virus. The virus from healthy turkeys in outbreak GB 97/6 induced clinical signs in 12/30 unvaccinated turkeys after challenge and 7/30 died. In unvaccinated chickens, challenge with this virus produced clinical signs in 25/30 birds and 21/30 died. In challenge experiments with the virus from outbreak GB 97/1 in chickens, 3/30 unvaccinated turkeys showed clinical signs and all three subsequently died. In contrast, 30/30 unvaccinated chickens challenged with this virus showed clinical signs and died. Vaccination did not prevent infection and excretion of either challenge virus. However, when compared with unvaccinated birds, vaccination reduced significantly the length of time virus was excreted and the overall proportion of swabs that were positive.

12.
J Med Chem ; 41(19): 3582-95, 1998 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-9733484

RESUMO

A series of (3R,5S)-omega-substituted-3-carboxy-3, 5-dihydroxyalkanoic acids have been synthesized and evaluated as inhibitors of the recombinant human form of ATP-citrate lyase. The best of these have Ki's in the 200-1000 nM range. As the corresponding thermodynamically favored gamma-lactone prodrugs, a number of compounds are able to inhibit cholesterol and fatty acid synthesis in HepG2 cells and reduce plasma triglyceride levels in vivo. The best of these, compound 77, is able to induce clear hypocholesterolemic and hypotriglyceridaemic responses when administered orally to rat and dog. These results provide evidence to support the hypothesis that compounds which inhibit ATP-citrate lyase have the potential to be a novel class of hypolipidemic agent, which possess combined hypocholesterolemic and hypotriglyceridemic activities.


Assuntos
ATP Citrato (pro-S)-Liase/antagonistas & inibidores , Inibidores Enzimáticos/síntese química , Ácidos Graxos/química , Furanos/síntese química , Hipolipemiantes/síntese química , Pró-Fármacos/síntese química , Administração Oral , Animais , Anticolesterolemiantes/administração & dosagem , Anticolesterolemiantes/síntese química , Anticolesterolemiantes/química , Anticolesterolemiantes/farmacologia , Linhagem Celular , Colesterol/sangue , Cães , Inibidores Enzimáticos/administração & dosagem , Inibidores Enzimáticos/química , Inibidores Enzimáticos/farmacologia , Ácidos Graxos/farmacologia , Furanos/administração & dosagem , Furanos/química , Furanos/farmacologia , Humanos , Hipolipemiantes/administração & dosagem , Hipolipemiantes/química , Hipolipemiantes/farmacologia , Lipídeos/biossíntese , Lipoproteínas VLDL/sangue , Pró-Fármacos/administração & dosagem , Pró-Fármacos/química , Pró-Fármacos/farmacologia , Ratos , Proteínas Recombinantes/antagonistas & inibidores , Relação Estrutura-Atividade , Triglicerídeos/sangue
13.
Biochemistry ; 37(28): 10087-93, 1998 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-9665713

RESUMO

Investigation of the inhibition of LDL-associated phospholipase A2 by monocyclic beta-lactams has shown that LDL phospholipase A2 is capable of hydrolyzing monocyclic-beta-lactams by a mechanism which shares many similarities to the hydrolysis of beta-lactams by beta-lactamases. We believe that this is the first demonstration of a serine-dependent lipase being able to hydrolyze an amide bond. Although 4-(phenylthio)-N-(4-phenyl-2-oxobutyl)azetidin-2-one, SB-216477, and its enantiomers are relatively modest covalent inactivators with kobs/[I] = 46 M-1 s-1 for the R enantiomer, analysis of the kinetics of inactivation and reactivation shows that these compounds act as slow-turnover substrates, presumably via an acylation-deacylation mechanism. The detection of a suprastoichiometric burst indicates that the pathway must be branched with the branching giving rise to the slow reactivation via a more stable covalent intermediate. Study of the two enantiomers of SB-216477 shows that LDL-associated phospholipase A2 is sensitive to the beta-lactam stereochemistry at C4. However, a common achiral intermediate is formed along the turnover pathway, and this must be at or immediately prior to the branch point.


Assuntos
Azetidinas/farmacologia , Lactamas , Lipoproteínas LDL/metabolismo , Fosfolipases A/antagonistas & inibidores , beta-Lactamas/farmacologia , 1-Alquil-2-acetilglicerofosfocolina Esterase , Azetidinas/metabolismo , Cromatografia Líquida de Alta Pressão , Ativação Enzimática/efeitos dos fármacos , Cinética , Fosfolipases A/metabolismo , Fosfolipases A2 , Análise Espectral , Estereoisomerismo , Especificidade por Substrato , beta-Lactamas/metabolismo
14.
J Clin Endocrinol Metab ; 82(10): 3203-7, 1997 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-9329339

RESUMO

The possible role of gonadal steroids in regulating sleep and circadian rhythms in humans has received relatively little attention despite the importance of the topic to several clinical syndromes. Pharmacologically induced hypogonadism, with and without gonadal steroid replacement, provides an opportunity to examine these questions within a controlled experimental design. We used leuprolide acetate, with and without testosterone replacement, to study the role of testosterone in the regulation of sleep and of melatonin, PRL, and TSH secretion in men. Results from 10 men revealed significant decreases in 24-h PRL levels and in the percentage and time of stage 4 sleep in the hypogonadal state compared with testosterone replacement. There were no differences in melatonin or TSH secretion or in the timing or duration of sleep between the two hormonal conditions. These results indicate that testosterone has relatively specific and discrete effects on sleep and hormonal rhythms in men.


Assuntos
Hormônios/metabolismo , Hipogonadismo/fisiopatologia , Caracteres Sexuais , Sono/efeitos dos fármacos , Testosterona/farmacologia , Adolescente , Adulto , Temperatura Corporal/fisiologia , Ritmo Circadiano , Humanos , Hipogonadismo/induzido quimicamente , Leuprolida , Masculino , Melatonina/metabolismo , Pessoa de Meia-Idade , Prolactina/metabolismo , Tireotropina/metabolismo
15.
Oral Surg Oral Med Oral Pathol ; 75(4): 479-82, 1993 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-8464613

RESUMO

The desmoplastic ameloblastoma is a rare histologic variant of ameloblastoma. This article presents a case of desmoplastic ameloblastoma with unique and complex histologic findings. The tumor, which was located in the anterior mandible, was treated by an anterior marginal resection with preservation of the inferior border of the mandible. The clinical, radiographic, surgical, and pathologic aspects of this unusual lesion are presented, and the relevant literature is reviewed.


Assuntos
Ameloblastoma/patologia , Neoplasias Mandibulares/patologia , Humanos , Masculino , Pessoa de Meia-Idade
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