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1.
Biol Reprod ; 96(1): 81-92, 2017 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-28395337

RESUMO

Although the positive effects of vaginal estrogens and the selective estrogen receptor modulator, ospemifene (OS), on the vaginal epithelium are well recognized, less is known regarding the effects of these therapies on the lower urinary tract or vaginal muscularis. Clinical evidence suggests that vaginally administered estrogen may improve overactive bladder-related symptoms. The objective of this study was to compare the effects of OS, vaginal conjugated equine estrogens (CEE), or both on the vaginal wall and lower urinary tract in a rat model of menopause. Contractile force of the bladder neck, dome, and external urethral sphincter at optimal field stimulation did not differ significantly among treatment groups. Pharmacologic responses to atropine, carbachol, and potassium chloride were similar among groups. Vaginal epithelial thickness and differentiation were differentially regulated by CEE or OS. Ospemifene altered epithelial differentiation pathways in vaginal epithelium in a unique way, and these effects were additive with local CEE. Unless contraindicated, the beneficial effects of vaginal CEE on the vaginal wall outweigh those of OS.


Assuntos
Estrogênios Conjugados (USP)/uso terapêutico , Estrogênios/uso terapêutico , Tamoxifeno/análogos & derivados , Uretra/efeitos dos fármacos , Bexiga Urinária/efeitos dos fármacos , Vagina/efeitos dos fármacos , Administração Intravaginal , Administração Oral , Animais , Avaliação Pré-Clínica de Medicamentos , Estrogênios/farmacologia , Estrogênios Conjugados (USP)/farmacologia , Feminino , Menopausa , Distribuição Aleatória , Ratos Sprague-Dawley , Tamoxifeno/farmacologia , Tamoxifeno/uso terapêutico
2.
Biol Reprod ; 92(2): 43, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25537371

RESUMO

The objective of this study was to compare the effects of systemic and local estrogen treatment on collagen assembly and biomechanical properties of the vaginal wall. Ovariectomized nulliparous rats were treated with estradiol or conjugated equine estrogens (CEEs) either systemically, vaginal CEE, or vaginal placebo cream for 4 wk. Low-dose local CEE treatment resulted in increased vaginal epithelial thickness and significant vaginal growth without uterine hyperplasia. Furthermore, vaginal wall distensibility increased without compromise of maximal force at failure. Systemic estradiol resulted in modest increases in collagen type I with no change in collagen type III mRNA. Low-dose vaginal treatment, however, resulted in dramatic increases in both collagen subtypes whereas moderate and high dose local therapies were less effective. Consistent with the mRNA results, low-dose vaginal estrogen resulted in increased total and cross-linked collagen content. The inverse relationship between vaginal dose and collagen expression may be explained in part by progressive downregulation of estrogen receptor-alpha mRNA with increasing estrogen dose. We conclude that, in this menopausal rat model, local estrogen treatment increased total and cross-linked collagen content and markedly stimulated collagen mRNA expression in an inverse dose-effect relationship. High-dose vaginal estrogen resulted in downregulation of estrogen receptor-alpha and loss of estrogen-induced increases in vaginal collagen. These results may have important clinical implications regarding the use of local vaginal estrogen therapy and its role as an adjunctive treatment in women with loss of vaginal support.


Assuntos
Colágeno/metabolismo , Estradiol/administração & dosagem , Estrogênios Conjugados (USP)/administração & dosagem , Vagina/efeitos dos fármacos , Administração Intravaginal , Administração Oral , Animais , Fenômenos Biomecânicos/efeitos dos fármacos , Feminino , Ratos , Útero/efeitos dos fármacos , Útero/metabolismo , Vagina/metabolismo , Cremes, Espumas e Géis Vaginais
3.
Exp Mol Pathol ; 99(3): 702-6, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26546836

RESUMO

BACKGROUND: Human papillomavirus (HPV) is a highly prevalent sexually transmitted virus causing cytological alterations that precede cervical cancer. Approximately 130 genotypes have been sequenced. Low-grade squamous intraepithelial lesions (LSIL) are the most frequent cytological alteration and have an uncertain behavior. OBJECTIVES: To analyze the frequency of HPV types in LSIL and their association with the regression, persistence or progression of these lesions. METHODS: A cohort study of forty patients with LSIL cytology was conducted from December 2007 to March 2011. The follow-up lasted two years and included cytology and colposcopy. HPV detection was performed using PCR, and genotyping was performed using PCR-specific and RFLP techniques. RESULTS: DNA-HPV was detected in 87% (35/40) of the cases, with oncogenic HPV accounting for 76%; type 16 in 32% (11/35) and type 18 in 20%. LSIL regression, persistence and progression rates at the end of the study were 60%, 23% and 17%, respectively. There was 50% regression in lesions in the high oncogenic risk group (types 16 and 18). CONCLUSION: HPV 16 was the most frequent genotype found in LSIL. The persistence and progression of the LSIL were related to the persistence of oncogenic HPV. The longer the follow-up time, the lower the LSIL persistence rate and the higher its regression rate; the progression rate remained stable. In addition to the presence of oncogenic HPV, other factors are necessary for the progression of LSIL.


Assuntos
Infecções por Papillomavirus/virologia , Lesões Intraepiteliais Escamosas Cervicais/patologia , Lesões Intraepiteliais Escamosas Cervicais/virologia , Progressão da Doença , Feminino , Genótipo , Humanos , Papillomaviridae/genética , Infecções por Papillomavirus/complicações , Reação em Cadeia da Polimerase , Polimorfismo de Fragmento de Restrição
4.
Nat Mater ; 12(4): 332-6, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23353629

RESUMO

Irradiating a ferromagnet with a femtosecond laser pulse is known to induce an ultrafast demagnetization within a few hundred femtoseconds. Here we demonstrate that direct laser irradiation is in fact not essential for ultrafast demagnetization, and that electron cascades caused by hot electron currents accomplish it very efficiently. We optically excite a Au/Ni layered structure in which the 30 nm Au capping layer absorbs the incident laser pump pulse and subsequently use the X-ray magnetic circular dichroism technique to probe the femtosecond demagnetization of the adjacent 15 nm Ni layer. A demagnetization effect corresponding to the scenario in which the laser directly excites the Ni film is observed, but with a slight temporal delay. We explain this unexpected observation by means of the demagnetizing effect of a superdiffusive current of non-equilibrium, non-spin-polarized electrons generated in the Au layer.

5.
J Chem Phys ; 134(13): 134102, 2011 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-21476738

RESUMO

Different computational methods are employed to calculate excitation energies of the carbon atom. Explicitly correlated wave functions have been obtained in a Variational Monte Carlo calculation. Fixed node Diffusion Monte Carlo calculations for the lowest energy excited states of a given symmetry are reported. A systematic and quantitative analysis of the performance of the different schemes in the calculation of the excitation energy of up to 27 excited states of the carbon atom is carried out. The quality of the different methods have been studied in terms of the deviation with respect to the experimental excitation energies. A good agreement with the experimental values has been reached.

6.
Female Pelvic Med Reconstr Surg ; 27(1): 39-45, 2021 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-31008776

RESUMO

OBJECTIVES: To assess impact of a decision aid video in Latina patients with symptomatic pelvic organ prolapse (POP) on knowledge, satisfaction and decisional conflict related to initial treatment selection. METHODS: Pilot study with randomized prospective design. Thirty Latina women with symptomatic POP were randomized to a decision aid intervention plus standard care (N = 15) or standard care alone (N = 15) group. Decision aid intervention consisted of a 10-minute video presented at time of initial evaluation for POP. Outcome measures included the Prolapse and Incontinence Knowledge Quiz ("Knowledge"), the Satisfaction with Decision ("Satisfaction") and Decisional Conflict (DCS) scales, and were assessed at 4 different timepoints: after initial visit, and at 1, 3 and 6 months after. Data was analyzed using repeated-measures ANOVA and pairwise between-group comparisons. RESULTS: Demographic and baseline data were similar between groups. There was a significant interaction between groups and time on the Knowledge scores (P = 0.03). Knowledge scores were higher at the initial visit in the intervention group (10.6 ± 0.8 vs 9.53 ± 1.4, P = 0.014). Satisfaction scores were lower in the intervention group on longitudinal analysis, indicating higher satisfaction (P = 0.02). There was no difference on overall Decisional Conflict scores between groups. The intervention group had lower scores on the "effective decision" DCS subscale at 3 and 6 months and "informed" DCS subscale at 3 months. CONCLUSIONS: A decision aid video intervention in Latina women with POP used at the time of initial evaluation may help the patient make a more informed treatment decision by increasing condition-related knowledge and lead to greater long-term satisfaction.


Assuntos
Tomada de Decisões , Técnicas de Apoio para a Decisão , Prolapso de Órgão Pélvico/terapia , Gravação em Vídeo , Idoso , Feminino , Hispânico ou Latino , Humanos , Pessoa de Meia-Idade , Prolapso de Órgão Pélvico/diagnóstico , Projetos Piloto , Estudos Prospectivos , Autorrelato
7.
J Neurosci Res ; 88(3): 620-9, 2010 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-19795371

RESUMO

Intrastriatal injection of quinolinic acid (QUIN) to rodents reproduces some biochemical, morphological, and behavioral characteristics of Huntington's disease. NAD(P)H oxidase is an enzymatic complex that catalyzes superoxide anion (O(2).(-)) production from O(2) and NADPH. The present study evaluated the role of NAD(P)H oxidase in the striatal damage induced by QUIN (240 nmol/microl) in adult male Wistar rats by means of apocynin (APO; 5 mg/kg i.p.), a specific NAD(P)H oxidase inhibitor. Rats were given APO 30 min before and 1 hr after QUIN injection or only 30 min after QUIN injection. NAD(P)H oxidase activity was measured in striatal homogenates by O2(*)(-) production. QUIN infusion to rats significantly increased striatal NAD(P)H oxidase activity (2 hr postlesion), whereas APO treatments decreased the QUIN-induced enzyme activity (2 hr postlesion), lipid peroxidation (3 hr postlesion), circling behavior (6 days postlesion), and histological damage (7 days postlesion). The addition of NADH to striatal homogenates increased NAD(P)H oxidase activity in striata from QUIN-treated animals but not from sham rats. Interestingly, O2(*)(-) production in QUIN-lesioned striata was unaffected by the addition of substrates for intramitochondrial O2(*)(-) production, xanthine oxidase and nitric oxide synthase, suggesting that NAD(P)H oxidase may be the main source of O2(*)(-) in QUIN-treated rats. Moreover, the administration of MK-801 to rats as a pretreatment resulted in a complete prevention of the QUIN-induced NAD(P)H activation, suggesting that this toxic event is completely dependent on N-methyl-D-aspartate receptor overactivation. Our results also suggest that NAD(P)H oxidase is involved in the pathogenic events linked to excitotoxic/prooxidant conditions.


Assuntos
Acetofenonas/farmacologia , Corpo Estriado/efeitos dos fármacos , Doença de Huntington/tratamento farmacológico , NADPH Oxidases/metabolismo , Fármacos Neuroprotetores/farmacologia , Animais , Corpo Estriado/metabolismo , Corpo Estriado/patologia , Modelos Animais de Doenças , Doença de Huntington/induzido quimicamente , Doença de Huntington/metabolismo , Peroxidação de Lipídeos/efeitos dos fármacos , Masculino , Malondialdeído/metabolismo , Atividade Motora/efeitos dos fármacos , NADPH Oxidases/antagonistas & inibidores , Óxido Nítrico Sintase/metabolismo , Carbonilação Proteica/efeitos dos fármacos , Ácido Quinolínico , Ratos , Ratos Wistar , Superóxidos/metabolismo , Fatores de Tempo , Xantina Oxidase/metabolismo
9.
J Phys Chem A ; 114(4): 1953-6, 2010 Feb 04.
Artigo em Inglês | MEDLINE | ID: mdl-20055398

RESUMO

The ground state and the LS terms coming from the ground-state configuration, [Ar]-3d(6)4s(2), of the iron atom are studied by carrying out an all electron Variational Monte Carlo calculation. Explicitly correlated trial functions including near degeneracy effects are used. The effect of electronic correlations and the importance of near degeneracy effects are systematically analyzed for the states here considered and compared with the experimental values. Correlations are important to reproduce, even qualitatively, the low-lying spectrum of this atom. A significant quantitative improvement when comparing with the experimental values is achieved when near degeneracy is considered along with dynamic correlations in the variational trial wave function. Finally, the effect of relativity on the results here reported is discussed.

10.
J Chem Phys ; 133(6): 064102, 2010 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-20707556

RESUMO

Nonrelativistic frozen nucleus all-electron Quantum Monte Carlo ground state energies of positive and negative ions Li(+) to Ar(+) and Li(-) to Cl(-), respectively, are reported. Explicitly correlated wave functions with a single configuration model function times a Jastrow factor are employed for all of the systems studied. The accuracy obtained for the ions in the third period is similar to that reached for the ions in the second one. For those ions with a stronger multiconfiguration nature a restricted multiconfiguration expansion has been employed. The ground state energy here obtained for the charged species shows a similar quality to that reached for neutral atoms. Starting from those results, ionization potentials and electron affinities are calculated.

11.
Science ; 276(5318): 1551-5, 1997 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-9171056

RESUMO

In primary visual cortex of higher mammals neurons are grouped according to their orientation preference, forming "pinwheels" around "orientation centers." Although the general structure of orientation maps is largely resolved, the microscopic arrangement of neuronal response properties in the orientation centers has remained elusive. The tetrode technique, enabling multiple single-unit recordings, in combination with intrinsic signal imaging was used to reveal the fine-grain structure of orientation maps in these locations. The results show that orientation centers represent locations where orientation columns converge containing normal, sharply tuned neurons of different orientation preference lying in close proximity.


Assuntos
Mapeamento Encefálico , Neurônios/fisiologia , Córtex Visual/fisiologia , Potenciais de Ação , Animais , Gatos , Diagnóstico por Imagem , Modelos Estatísticos
12.
J Chem Phys ; 131(4): 044115, 2009 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-19655845

RESUMO

All-electron quantum Monte Carlo energies are reported for the ground state of the atoms Li to Ar. The present work is mainly focused on the atoms Na to Ar as well as in those that have a stronger multiconfiguration nature, i.e., Be, B, and C and Mg, Al, and Si. Explicitly correlated wave functions with a single configuration model function times a Jastrow factor are employed for all of the atoms studied. The accuracy obtained for the atoms Na to Ar is similar to that reached for the atoms Li to Ne. In addition, a restricted multiconfiguration expansion has been employed for the atoms Be, B, and C and Mg, Al, and Si obtaining accurate results. Near degeneracy and the effect of other configurations are systematically analyzed for these systems, at both variational and diffusion Monte Carlo levels.

13.
Inhal Toxicol ; 21(11): 906-12, 2009 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-19459774

RESUMO

Cigarette smoke is a complex mixture of various toxic substances that are capable of initiating oxidative damage and promoting blood platelet alterations. In this study, we investigated the activities of the ectoenzymes NTPDase (ectonucleoside triphosphate diphosphohydrolase, CD39) and 5'-nucleotidase (CD73) in platelets as well as adenosine deaminase (ADA) in the plasma of rats exposed to aged and diluted sidestream smoke during 4 weeks. The rats were divided into two groups: I (control) and II (exposed to smoke). After the exposure period, blood was collected and the platelets and plasma were separated for enzymatic assay. The results demonstrated that NTPDase (with ATP as substrate) and 5'-nucleotidase (AMP as substrate) activities were significantly higher in group II (p < 0.05) as compared to group I, while no significant difference was observed for NTPDase with ADP as substrate. The ADA activity was significantly reduced in group II (p < 0.05) as compared with group I. Platelet aggregation was significantly increased in group II (p < 0.05) as compared with group I. We suggest that these alterations in the activity of enzymes from the purinergic system are associated with an increase in platelet aggregation. However, our study has demonstrated that the organism tries to compensate for this enhanced aggregation by increasing hydrolysis of AMP and reducing hydrolysis of adenosine, a potent inhibitor of aggregation and an important modulator of vascular tone.


Assuntos
Adenosina Desaminase/metabolismo , Adenosina Trifosfatases/metabolismo , Poluição por Fumaça de Tabaco/efeitos adversos , 5'-Nucleotidase/sangue , Adenosina/sangue , Animais , Gasometria , Plaquetas/enzimologia , Carboxihemoglobina/metabolismo , Concentração de Íons de Hidrogênio , Pulmão/enzimologia , Pulmão/patologia , Masculino , Agregação Plaquetária/efeitos dos fármacos , Fibrose Pulmonar/induzido quimicamente , Fibrose Pulmonar/patologia , Ratos , Ratos Wistar , Nicotiana/química
14.
J Phys Chem A ; 112(10): 2074-6, 2008 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-18220374

RESUMO

The domain Green's function Monte Carlo method has been used to calculate the ground-state energy of the atoms Sc through Zn. The fixed node approximation with single-configuration explicitly correlated wave functions is used. A comparison with variational Monte Carlo energies is carried out. The quality of the ground-state energies reported here is similar to that achieved for few-electron atoms using similar techniques.

15.
J Neurosci Methods ; 308: 197-204, 2018 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-30107206

RESUMO

BACKGROUND: Neosaxitoxin (NeoSTX) and related paralytics shellfish toxins has been successfully used as local anesthetic and muscle relaxants to treat a variety of ailments. The primary mechanism of action of these toxins occurs by blocking voltage-gated sodium channels with compounds such as TTX, lidocaine, or derivatives. However, most of these non-classical sodium channel blockers act with a reduced time effect as well as ensuing neurotoxicity. NEW METHOD: In this report, we show that the use of local NeoSTX injections inactivates the hippocampal neuronal activity reversibly with a by long-term dynamics, without neuronal damage. RESULTS: A single 10 ng/µl injection of NeoSTX in the dorsal CA1 region abolished for up to 48 h memory capacities and neuronal activity measured by the neuronal marker c-fos. After 72 h of toxin injection, the animals fully recover their memory capacities and hippocampal neuronal activity. The histological inspection of NeoSTX injected brain regions revealed no damage to the tissue or reactive gliosis, similar to vehicle injection. Acute electrophysiological recording in vivo shows, also, minimal spreading of the NeoSTX in the cerebral tissue. COMPARISON WITH EXISTING METHODS: Intracerebral NeoSTX injection showed longer effects than other voltage sodium channel blocker, with minimal spreading and no neuronal damage. CONCLUSION: NeoSTX is a new useful tool that reversibly inactivates different brains region for a long time, with minimal diffusion and without neuronal damage. Moreover, NeoSTX can be used as a valuable sodium channel blocker for many studies in vivo and with potential therapeutic uses.


Assuntos
Região CA1 Hipocampal/efeitos dos fármacos , Neurônios/efeitos dos fármacos , Saxitoxina/análogos & derivados , Bloqueadores dos Canais de Sódio/administração & dosagem , Memória Espacial/efeitos dos fármacos , Amnésia/induzido quimicamente , Animais , Região CA1 Hipocampal/fisiologia , Masculino , Neurônios/fisiologia , Ratos Sprague-Dawley , Reconhecimento Psicológico/efeitos dos fármacos , Saxitoxina/administração & dosagem
16.
Nat Commun ; 9(1): 1035, 2018 03 07.
Artigo em Inglês | MEDLINE | ID: mdl-29515124

RESUMO

"The technical support from SLAC Accelerator Directorate, Technology Innovation Directorate, LCLS laser division and Test Facility Division is gratefully acknowledged. We thank S.P. Weathersby, R.K. Jobe, D. McCormick, A. Mitra, S. Carron and J. Corbett for their invaluable help and technical assistance. Research at SLAC was supported through the SIMES Institute which like the LCLS and SSRL user facilities is funded by the Office of Basic Energy Sciences of the U.S. Department of Energy under Contract No. DE-AC02-76SF00515. The UED work was performed at SLAC MeV-UED, which is supported in part by the DOE BES SUF Division Accelerator & Detector R&D program, the LCLS Facility, and SLAC under contract Nos. DE-AC02-05-CH11231 and DE-AC02-76SF00515. Use of the Linac Coherent Light Source (LCLS), SLAC National Accelerator Laboratory, is supported by the U.S. Department of Energy, Office of Science, Office of Basic Energy Sciences under Contract No. DE-AC02-76SF00515."and"Work at BNL was supported by DOE BES Materials Science and Engineering Division under Contract No: DE-AC02-98CH10886. J.C. would like to acknowledge the support from National Science Foundation Grant No. 1207252. E.E.F. would like to acknowledge support from the U.S. Department of Energy (DOE), Office of Basic Energy Sciences (BES) under Award No. DE-SC0003678."This has been corrected in both the PDF and HTML versions of the Article.

17.
Nat Commun ; 9(1): 388, 2018 01 26.
Artigo em Inglês | MEDLINE | ID: mdl-29374151

RESUMO

Magnetostriction, the strain induced by a change in magnetization, is a universal effect in magnetic materials. Owing to the difficulty in unraveling its microscopic origin, it has been largely treated phenomenologically. Here, we show how the source of magnetostriction-the underlying magnetoelastic stress-can be separated in the time domain, opening the door for an atomistic understanding. X-ray and electron diffraction are used to separate the sub-picosecond spin and lattice responses of FePt nanoparticles. Following excitation with a 50-fs laser pulse, time-resolved X-ray diffraction demonstrates that magnetic order is lost within the nanoparticles with a time constant of 146 fs. Ultrafast electron diffraction reveals that this demagnetization is followed by an anisotropic, three-dimensional lattice motion. Analysis of the size, speed, and symmetry of the lattice motion, together with ab initio calculations accounting for the stresses due to electrons and phonons, allow us to reveal the magnetoelastic stress generated by demagnetization.

18.
Neuroscience ; 144(4): 1536-43, 2007 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-17187932

RESUMO

Many studies have now demonstrated that neurons in the visual cortex of cats and monkeys change their activity when stimuli are presented beyond their classical receptive field, and that these responses are not readily apparent from their receptive field properties. However few studies have been conducted to investigate the discharge properties of neurons in the visual cortex of animals when they are allow to freely view natural images. We employ tetrodes, which enable simultaneous and separable recordings of small numbers of neighboring neurons, to record 102 single units from 59 sites from areas 17 and 18 of two alert cats. While the animals viewed either natural images or black screens, they made frequent saccadic eye movements and gaze fixations. Fixations onto an image's location increased neuronal firing peaking at 80-100 ms after the fixation onset, to then decrease steadily with time despite continuous fixation. Saccades trigger a fast decrease in firing rate for both images and darkness. When we examined the incidence of correlated firing, we observed significant synchrony during the initial phases of visual fixations when the animals viewed natural scenes. Such synchrony was absent during saccadic eye movements and during eye movements in darkness. Our data revealed that scanning of natural scenes is associated with a rapid succession of distinct fixation-related activation patterns that included transient rate changes and excess coincident firing. The transient nature of these synchronization phenomena suggests a fast acting mechanism, which is in good agreement with the evidence that basic operations of scene analysis must be accomplished within a few tens of milliseconds in primary visual cortex.


Assuntos
Potenciais de Ação/fisiologia , Fixação Ocular/fisiologia , Neurônios/fisiologia , Reconhecimento Visual de Modelos/fisiologia , Córtex Visual/fisiologia , Vias Visuais/fisiologia , Animais , Gatos , Sincronização Cortical , Masculino , Orientação/fisiologia , Estimulação Luminosa , Tempo de Reação/fisiologia , Movimentos Sacádicos/fisiologia , Percepção Espacial/fisiologia , Campos Visuais/fisiologia
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