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1.
J Environ Manage ; 247: 829-839, 2019 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-31336348

RESUMO

Although wetlands remain threatened by human pressures and climate change, monitoring and managing them are challenging due to their high spatial and temporal dynamics within a fine-grained pattern. New satellite time-series at high temporal and spatial resolutions provide a promising opportunity to map and monitor wetlands. The objective of this study was to develop an operational method for managing valley bottom wetlands based on available free remote sensing data. The Potential, Existing, Efficient Wetlands (PEEW) approach was adapted to remote sensing data to delineate three wetland components: (1) potential wetlands, mapped from a digital terrain model derived from LiDAR data; (2) existing wetlands, delineated from land cover maps derived from Sentinel-1/2 time-series; and (3) efficient wetlands, identified from functional indicators (i.e. annual primary production, vegetation phenology, seasonality of carbon flux) derived from MODIS annual time-series. Soil and vegetation samples were collected in the field to calibrate and validate classification of remote sensing data. The method was applied to a 113 000 ha watershed in northwestern France. Results show that potential wetlands were successfully delineated (82% overall accuracy) and covered 21% of the watershed area, while 44% of existing wetlands had been lost. Small wetlands along headwater channels, which are considered as ordinary, cover 56% of wetland area in the watershed. Efficient wetlands were identified as contiguous pixels with a similar temporal functional trajectory. This method, based on free remote sensing data, provides a new perspective for wetland management. The method can identify sites where restoration measures should be prioritized and enables better understanding and monitoring of the influence of management practices and climate on wetland functions.


Assuntos
Tecnologia de Sensoriamento Remoto , Áreas Alagadas , Mudança Climática , Monitoramento Ambiental , França , Humanos , Solo
2.
Comput Methods Biomech Biomed Engin ; 21(5): 399-407, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29996696

RESUMO

We aim to maximize the pumping volume of a pulsatile ventricular assist device, where the diaphragm is covered with an endothelial cell layer. These cells are estimated to survive a cyclic strain up to fifteen percent. To increase the pumping volume under this strain constraint we use an approach based on corrugation of the diaphragm in its reference configuration. The paper explains the parametrization scheme for finding corrugation shapes, addresses modeling and evaluation schemes and reports on the results of a parameter study. The results show that corrugated diaphragm shapes are effective for increasing pumping volumes under a strain constraint.


Assuntos
Diafragma/anatomia & histologia , Coração Auxiliar , Teste de Materiais , Fluxo Pulsátil , Humanos , Modelos Teóricos , Pressão
3.
Lab Chip ; 18(13): 1844-1858, 2018 06 26.
Artigo em Inglês | MEDLINE | ID: mdl-29796561

RESUMO

Recapitulation of the tumor microenvironment is critical for probing mechanisms involved in cancer, and for evaluating the tumor-killing potential of chemotherapeutic agents, targeted therapies and immunotherapies. Microfluidic devices have emerged as valuable tools for both mechanistic studies and for preclinical evaluation of therapeutic agents, due to their ability to precisely control drug concentrations and gradients of oxygen and other species in a scalable and potentially high throughput manner. Most existing in vitro microfluidic cancer models are comprised of cultured cancer cells embedded in a physiologically relevant matrix, collocated with vascular-like structures. However, the recent emergence of immune checkpoint inhibitors (ICI) as a powerful therapeutic modality against many cancers has created a need for preclinical in vitro models that accommodate interactions between tumors and immune cells, particularly for assessment of unprocessed tumor fragments harvested directly from patient biopsies. Here we report on a microfluidic model, termed EVIDENT (ex vivo immuno-oncology dynamic environment for tumor biopsies), that accommodates up to 12 separate tumor biopsy fragments interacting with flowing tumor-infiltrating lymphocytes (TILs) in a dynamic microenvironment. Flow control is achieved with a single pump in a simple and scalable configuration, and the entire system is constructed using low-sorption materials, addressing two principal concerns with existing microfluidic cancer models. The system sustains tumor fragments for multiple days, and permits real-time, high-resolution imaging of the interaction between autologous TILs and tumor fragments, enabling mapping of TIL-mediated tumor killing and testing of various ICI treatments versus tumor response. Custom image analytic algorithms based on machine learning reported here provide automated and quantitative assessment of experimental results. Initial studies indicate that the system is capable of quantifying temporal levels of TIL infiltration and tumor death, and that the EVIDENT model mimics the known in vivo tumor response to anti-PD-1 ICI treatment of flowing TILs relative to isotype control treatments for syngeneic mouse MC38 tumors.


Assuntos
Técnicas Analíticas Microfluídicas/instrumentação , Modelos Biológicos , Microambiente Tumoral/imunologia , Animais , Carcinoma Pulmonar de Células não Pequenas/química , Carcinoma Pulmonar de Células não Pequenas/imunologia , Técnicas de Cultura de Células , Linhagem Celular Tumoral , Células Cultivadas , Desenho de Equipamento , Humanos , Processamento de Imagem Assistida por Computador/métodos , Neoplasias Pulmonares/química , Neoplasias Pulmonares/imunologia , Linfócitos/citologia , Linfócitos/metabolismo , Camundongos , Técnicas Analíticas Microfluídicas/métodos
4.
Curr Oncol ; 22(5): e332-5, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26628872
5.
Gynecol Obstet Fertil ; 41(9): 511-4, 2013 Sep.
Artigo em Francês | MEDLINE | ID: mdl-23972925

RESUMO

OBJECTIVE: To evaluate the efficacy and safety of ovulation triggering by agonists in antagonists IVF cycles with fresh embryo transfer in modulating low HCG dose for luteal phase support in patients at risk of ovarian hyperstimulation syndrome (OHSS). PATIENTS AND METHODS: In an observational study from September 2011 to March 2013, we triggered with agonist 107 cycles with OHSS risk, we initially triggered 39 cycles with 2 doses of Triptorelin 0.1 mg. Injection of 1500 IU HCG was performed one hour after the pick up and a second injection of 1500 IU was made 5 days later (group 1) combined with 400 mg of natural progesterone vaginally. In the following 68 cycles we removed the second HCG injection and increased to 600 mg vaginal progesterone associated with E2 4 mg orally (group 2). RESULTS: Group 1: the ongoing pregnancy rate and birth rate in fresh cycle is respectively 37.1% and 34.3% and the cumulative ongoing pregnancy rate and birth rate per patient is 43.6% and 41%. We recorded three late onset OHSS in pregnant women. Group 2: ongoing pregnancy rate in fresh cycle is 39.6%, the current cumulative ongoing pregnancy rate per patient was 45.6%. We observed a case of early onset OHSS. DISCUSSION AND CONCLUSION: Triggering with agonist and administering an injection of 1500 IU of HCG the day of the pick up appears to be effective in women at risk of OHSS. The exclusion of all OHSS is still not reached. The search for the best protocol and its indications should continue.


Assuntos
Fertilização in vitro , Hormônio Liberador de Gonadotropina/agonistas , Fase Luteal , Síndrome de Hiperestimulação Ovariana/prevenção & controle , Indução da Ovulação/métodos , Administração Intravaginal , Gonadotropina Coriônica/administração & dosagem , Transferência Embrionária , Feminino , Humanos , Luteolíticos/administração & dosagem , Indução da Ovulação/efeitos adversos , Gravidez , Progesterona/administração & dosagem , Fatores de Risco , Pamoato de Triptorrelina/administração & dosagem
6.
J Gynecol Obstet Biol Reprod (Paris) ; 41(2): 145-50, 2012 Apr.
Artigo em Francês | MEDLINE | ID: mdl-22226634

RESUMO

OBJECTIVE: To assess the feasibility and the results on fertility of tubal hysteroscopic proximal occlusion with Essure(®) micro-insert in women with hydrosalpinges. PATIENTS AND METHODS: Thirteen infertile women with hydrosalpinges, who underwent hysteroscopic tubal exclusion by Essure(®) prior to IVF procedure. RESULTS: The placement of micro-insert was feasible and easy in every patient, with no intra-operative complication. Only one postoperative infectious complication (pyosalpinx) occurred. We report a 64 % rate of pregnancy, and a 18 % rate of normally ongoing pregnancies with no Essure(®)-related complication. CONCLUSION: Hydrosalpinges occlusion by Essure(®) device might be an easy and safe alternative to laparoscopic treatment, with successful results on fertility and without adverse effects on pregnancy outcomes.


Assuntos
Doenças das Tubas Uterinas/complicações , Doenças das Tubas Uterinas/cirurgia , Fertilização in vitro/métodos , Histeroscopia , Infertilidade Feminina/etiologia , Adulto , Feminino , Humanos , Infertilidade Feminina/terapia , Gravidez , Esterilização Tubária/instrumentação , Esterilização Tubária/métodos
7.
J Gynecol Obstet Biol Reprod (Paris) ; 40(6): 498-502, 2011 Oct.
Artigo em Francês | MEDLINE | ID: mdl-21514077

RESUMO

OBJECTIVE: To evaluate by the birth rate the impact of the number of days of estrogens continued beyond the menses in a four days estradiol IVF antagonist programming cycles. PATIENTS AND METHODS: Retrospective study from September 2004 to January 2009 among women of age ranging between 25 and 38 years. Four milligrams of provames is prescribed 3 to 5 days before the theorical menses and continued until the beginning day of stimulation, which is distributed equitably between Thursday and Sunday. The birth rate is evaluated according to the number of days of estrogen continued beyond the menses within a limit from 1 to 8. RESULTS: No significant difference appears neither in the duration of stimulation, in the quantity of gonadotrophin, the oocytes pick up, nor in the rate of birth between the groups. CONCLUSION: The programming by estrogens of the antagonist IVF cycles implies a variable number of days of estrogens continued beyond the menses, which does not seem to affect the birth rate.


Assuntos
Antagonistas de Estrogênios/uso terapêutico , Estrogênios/administração & dosagem , Fertilização in vitro/métodos , Menstruação/efeitos dos fármacos , Indução da Ovulação/métodos , Adulto , Esquema de Medicação , Antagonistas de Estrogênios/efeitos adversos , Estrogênios/efeitos adversos , Estrogênios/farmacologia , Feminino , Fármacos para a Fertilidade Feminina/efeitos adversos , Fármacos para a Fertilidade Feminina/uso terapêutico , Gonadotropinas/efeitos adversos , Gonadotropinas/farmacologia , Gonadotropinas/uso terapêutico , Humanos , Ciclo Menstrual/efeitos dos fármacos , Ciclo Menstrual/fisiologia , Menstruação/fisiologia , Periodicidade , Gravidez , Taxa de Gravidez , Estudos Retrospectivos , Fatores de Tempo
8.
Magn Reson Med ; 65(5): 1437-47, 2011 May.
Artigo em Inglês | MEDLINE | ID: mdl-21287591

RESUMO

Diffusion-weighted imaging plays important roles in cancer diagnosis, monitoring, and treatment. Although most applications measure restricted diffusion by tumor cellularity, diffusion-weighted imaging is also sensitive to vascularity through the intravoxel incoherent motion effect. Hypervascularity can confound apparent diffusion coefficient measurements in breast cancer. We acquired multiple b-value diffusion-weighted imaging at 3 T in a cohort of breast cancer patients and performed biexponential intravoxel incoherent motion analysis to extract tissue diffusivity (D(t)), perfusion fraction (f(p)), and pseudodiffusivity (D(p)). Results indicated significant differences between normal fibroglandular tissue and malignant lesions in apparent diffusion coefficient mean (±standard deviation) values (2.44 ± 0.30 vs. 1.34 ± 0.39 µm(2)/msec, P < 0.01) and D(t) (2.36 ± 0.38 vs. 1.15 ± 0.35 µm(2)/msec, P < 0.01). Lesion diffusion-weighted imaging signals demonstrated biexponential character in comparison to monoexponential normal tissue. There is some differentiation of lesion subtypes (invasive ductal carcinoma vs. other malignant lesions) with f(p) (10.5 ± 5.0% vs. 6.9 ± 2.9%, P = 0.06), but less so with D(t) (1.14 ± 0.32 µm(2)/msec vs. 1.18 ± 0.52 µm(2)/msec, P = 0.88) and D(p) (14.9 ± 11.4 µm(2)/msec vs. 16.1 ± 5.7 µm(2)/msec, P = 0.75). Comparison of intravoxel incoherent motion biomarkers with contrast enhancement suggests moderate correlations. These results suggest the potential of intravoxel incoherent motion vascular and cellular biomarkers for initial grading, progression monitoring, or treatment assessment of breast tumors.


Assuntos
Neoplasias da Mama/patologia , Imagem de Difusão por Ressonância Magnética/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Biópsia , Meios de Contraste , Feminino , Gadolínio DTPA , Humanos , Pessoa de Meia-Idade , Movimento , Neovascularização Patológica/patologia , Software
9.
Gynecol Obstet Fertil ; 38(1): 18-22, 2010 Jan.
Artigo em Francês | MEDLINE | ID: mdl-20022282

RESUMO

OBJECTIVE: Assess the efficiency of estradiol programming in In Vitro Fertilization (IVF) with antagonists by comparing with classical long luteal agonist protocol. PATIENTS AND METHODS: It is a prospective randomized study, comparing 426 cycles in the arm estradiol antagonist with 412 cycles in the arm long agonist. Estradiol 4 mg/day begins on the 25th day of the previous cycle and continues during the menses until the first day of the stimulation which is from Thursday to Sunday whatever the beginning of the menses. The luteal protocol use Decapeptyl 0,1mg which begins on the 20th day of the previous cycle. RESULTS: Our two populations are similar. No pick-up has been done on Sunday. We have got significantly less oocytes and embryos in estradiol-antagonist (6,8+/-5,3 vs 7,6+/-5,7) and (3,7+/-3,2 vs 4,1+/-3,6) respectively. The ongoing pregnancy rate is comparable in the two groups: 28,6 % for estradiol antagonist 27,9 % for agonist for the whole population and 37 % vs 34,8 % respectively when at least one top embryo was transferred. DISCUSSION AND CONCLUSION: Programming antagonist cycles with estradiol allows the organization of the center; it is easy to implement and seems to give results as good as a long agonist protocol.


Assuntos
Estradiol/administração & dosagem , Antagonistas de Estrogênios/administração & dosagem , Fertilização in vitro/métodos , Luteolíticos/administração & dosagem , Indução da Ovulação/métodos , Pamoato de Triptorrelina/administração & dosagem , Adulto , Transferência Embrionária , Feminino , Hormônio Liberador de Gonadotropina/agonistas , Humanos , Recuperação de Oócitos , Oócitos/crescimento & desenvolvimento , Gravidez , Taxa de Gravidez , Estudos Prospectivos
10.
J Neurochem ; 79(1): 152-60, 2001 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11595767

RESUMO

The neurotoxic actions of methamphetamine (METH) may be mediated in part by reactive oxygen species (ROS). Methamphetamine administration leads to increases in ROS formation and lipid peroxidation in rodent brain; however, the extent to which proteins may be modified or whether affected brain regions exhibit similar elevations of lipid and protein oxidative markers have not been investigated. In this study we measured concentrations of TBARs, protein carbonyls and monoamines in various mouse brain regions at 4 h and 24 h after the last of four injections of METH (10 mg/kg/injection q 2 h). Substantial increases in TBARs and protein carbonyls were observed in the striatum and hippocampus but not the frontal cortex nor the cerebellum of METH-treated mice. Furthermore, lipid and protein oxidative markers were highly correlated within each brain region. In the hippocampus and striatum elevations in oxidative markers were significantly greater at 24 h than at 4 h. Monoamine levels were maximally reduced within 4 h (striatal dopamine [DA] by 95% and serotonin [5-HT] in striatum, cortex and hippocampus by 60-90%). These decrements persisted for 7 days after METH, indicating effects reflective of nerve terminal damage. Interestingly, NE was only transiently depleted in the brain regions investigated (hippocampus and cortex), suggesting a pharmacological and non-toxic action of METH on the noradrenergic nerve terminals. This study provides the first evidence for concurrent formation of lipid and protein markers of oxidative stress in several brain regions of mice that are severely affected by large neurotoxic doses of METH. Moreover, the differential time course for monoamine depletion and the elevations in oxidative markers indicate that the source of oxidative stress is not derived directly from DA or 5HT oxidation.


Assuntos
Biomarcadores/análise , Encéfalo/efeitos dos fármacos , Encéfalo/metabolismo , Peroxidação de Lipídeos , Metanfetamina/farmacologia , Proteínas do Tecido Nervoso/metabolismo , Ácido 3,4-Di-Hidroxifenilacético/metabolismo , Animais , Monoaminas Biogênicas/metabolismo , Cerebelo/efeitos dos fármacos , Cerebelo/metabolismo , Córtex Cerebral/efeitos dos fármacos , Córtex Cerebral/metabolismo , Corpo Estriado/efeitos dos fármacos , Corpo Estriado/metabolismo , Dopamina/metabolismo , Hipocampo/efeitos dos fármacos , Hipocampo/metabolismo , Ácido Hidroxi-Indolacético/metabolismo , Masculino , Camundongos , Oxirredução , Estresse Oxidativo , Espécies Reativas de Oxigênio/metabolismo , Serotonina/metabolismo , Substâncias Reativas com Ácido Tiobarbitúrico/análise
12.
Environ Manage ; 27(3): 451-61, 2001 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-11148769

RESUMO

For the last 20 years, human-wildlife conflicts have been rapidly increasing in towns. Although people want "greener" cities, the expansion of disliked species causes problems that are difficult to manage and to reduce. The complexity of the numerous factors involved in these human-wildlife relations needs the development of a comprehensive tool for urban planners. Today, with the development of computers and geographical information systems, it is easier to analyze and combine different spatial data as methods used for the management of risks in studies of natural hazards. Here we present a method for assessing and mapping the risk in cases of human-wildlife conflict. An application to starling management in a town in western France will show the efficiency of our methods to combine information given by a network of experts and to highlight higher risk sites. The map of risk provides a spatial result useful for comprehension, communication between people and agencies, and public education.


Assuntos
Animais Selvagens , Simulação por Computador , Conservação dos Recursos Naturais , Animais , Mordeduras e Picadas/prevenção & controle , Humanos , Saúde Pública , Medição de Risco , População Urbana , Zoonoses/transmissão
13.
J Neurochem ; 74(4): 1656-65, 2000 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-10737624

RESUMO

Defects in mitochondrial energy metabolism have been implicated in the pathology of several neurodegenerative disorders. In addition, the reactive metabolites generated from the metabolism and oxidation of the neurotransmitter dopamine (DA) are thought to contribute to the damage to neurons of the basal ganglia. We have previously demonstrated that infusions of the metabolic inhibitor malonate into the striata of mice or rats produce degeneration of DA nerve terminals. In the present studies, we demonstrate that an intrastriatal infusion of malonate induces a substantial increase in DA efflux in awake, behaving mice as measured by in vivo microdialysis. Furthermore, pretreatment of mice with tetrabenazine (TBZ) or the TBZ analogue Ro 4-1284 (Ro-4), compounds that reversibly inhibit the vesicular storage of DA, attenuates the malonate-induced DA efflux as well as the damage to DA nerve terminals. Consistent with these findings, the damage to both DA and GABA neurons in mesencephalic cultures by malonate exposure was attenuated by pretreatment with TBZ or Ro-4. Treatment with these compounds did not affect the formation of free radicals or the inhibition of oxidative phosphorylation resulting from malonate exposure alone. Our data suggest that DA plays an important role in the neurotoxicity produced by malonate. These findings provide direct evidence that inhibition of succinate dehydrogenase causes an increase in extracellular DA levels and indicate that bioenergetic defects may contribute to the pathogenesis of chronic neurodegenerative diseases through a mechanism involving DA.


Assuntos
Corpo Estriado/citologia , Dopamina/fisiologia , Malonatos/farmacologia , Proteínas de Membrana Transportadoras , Neurônios/metabolismo , Neuropeptídeos , 2-etil-1,3,4,6,7,11b-hexaidro-3-isobutil-9,10-dimetoxi-2H-benzo(a)quinolizin-2-ol/farmacologia , Ácido 3,4-Di-Hidroxifenilacético/metabolismo , Inibidores da Captação Adrenérgica/farmacologia , Animais , Transporte Biológico/efeitos dos fármacos , Transporte Biológico/fisiologia , Radioisótopos de Carbono , Células Cultivadas , Corpo Estriado/efeitos dos fármacos , Corpo Estriado/metabolismo , Dopamina/farmacocinética , Metabolismo Energético/efeitos dos fármacos , Metabolismo Energético/fisiologia , Radicais Livres/metabolismo , Ácido Láctico/metabolismo , Masculino , Glicoproteínas de Membrana/metabolismo , Camundongos , Microdiálise , Degeneração Neural/induzido quimicamente , Degeneração Neural/metabolismo , Neurônios/efeitos dos fármacos , Doença de Parkinson/metabolismo , Terminações Pré-Sinápticas/efeitos dos fármacos , Vesículas Sinápticas/metabolismo , Tetrabenazina/farmacologia , Trítio , Proteínas Vesiculares de Transporte de Aminas Biogênicas , Ácido gama-Aminobutírico/metabolismo , Ácido gama-Aminobutírico/farmacocinética
15.
Dermatol Surg ; 25(8): 597-600, 1999 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-10491040

RESUMO

BACKGROUND: Carbon dioxide (CO2) lasers and phenol chemical peels have been used extensively for facial skin resurfacing. OBJECTIVE: The purpose of this study is to compare the histologic effects of phenol chemical peels and CO2 laser ablations. METHODS: Local preauricular areas were treated with lasers on one side of the face and a phenol peel on the other. One day after the procedures, the affected areas were biopsied for histologic evaluation. The areas were biopsied again after 3 months. RESULTS: The initial biopsies demonstrated that the CO2 lasers ablate more superficial skin than the peels, but the 3-month biopsy specimens showed that the zone of new collagen formation was thicker as a result of the phenol peels. CONCLUSION: With the parameters used in this study, phenol peels resulted in the formation of a thicker zone of collagen despite the deeper ablation depth of the laser.


Assuntos
Abrasão Química , Dermabrasão/instrumentação , Terapia a Laser , Pele/patologia , Biópsia , Seguimentos , Humanos , Fenol , Pele/efeitos dos fármacos , Cicatrização/fisiologia
16.
Dermatol Surg ; 25(6): 455-62, 1999 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-10469092

RESUMO

BACKGROUND: Excessive subcutaneous adipose tissue is typically treated by physically removing the fat through liposuction, but cost and accessibility have popularized alternative treatments for reducing adipose tissue thickness. OBJECTIVE: The purpose of this study was to test the absolute and relative effectiveness of a liposome-encapsulated caffeine-based cream in modifying subcutaneous adipose tissue. METHODS: Forty-one patients consented and completed the double-blind, single-center, placebo-controlled study. Caliper measurements, tape measurements, and photographs were taken over a 2-month period. RESULTS: Both concentrations of the cream were found to significantly reduce the thickness of the adipose tissue in all areas of the body. In addition, the more concentrated cream was significantly more effective than the less concentrated cream in the areas of the hips and the triceps. CONCLUSION: The caffeine-based liposome-encapsulated cream significantly reduced the thickness of the subcutaneous fat over a 2-month period.


Assuntos
Tecido Adiposo/efeitos dos fármacos , Cafeína/administração & dosagem , Xantinas/administração & dosagem , Adulto , Idoso , Antropometria , Cafeína/farmacologia , Relação Dose-Resposta a Droga , Método Duplo-Cego , Portadores de Fármacos , Feminino , Humanos , Lipossomos , Masculino , Pessoa de Meia-Idade , Pomadas , Xantinas/farmacologia
17.
J Pediatr Adolesc Gynecol ; 12(2): 83-9, 1999 May.
Artigo em Inglês | MEDLINE | ID: mdl-10326193

RESUMO

STUDY OBJECTIVES: The purpose of this study was to determine whether, among childbearing adolescents, ego development was associated with intention to breast-feed and with actual breast-feeding behavior at birth and at 2 weeks postpartum. In addition, we sought to determine whether positive attitudes toward breast-feeding influenced pregnant adolescents' intentions to breast-feed and actual breast-feeding at the hospital and at 2 weeks postpartum. We hypothesized that adolescents with higher levels of ego development and positive attitudes toward breast-feeding would be more likely to intend to breast-feed and to actually breast-feed. DESIGN: Prospective cohort study of pregnant adolescents who completed questionnaires, Loevinger's Sentence Completion Tests, and attitudes toward breast-feeding scales before delivery and a follow-up questionnaire at 2 weeks postpartum assessing feeding practice in the hospital and at 2 weeks postpartum. SETTING: Two adolescents' clinics and two "teen-and-tot" clinics in urban teaching hospitals. PARTICIPANTS: Fourteen- to 22-year-old pregnant adolescents who had never given birth and who planned to carry their pregnancy to term and parent their children. MAIN OUTCOME MEASURES: 1) Intended feeding practice during pregnancy, 2) feeding method in the hospital, and 3) feeding method at 2 weeks postpartum. RESULTS: Of the 125 subjects enrolled in the study, 106 were at 2 weeks postpartum or more. Of these 106 participants, 75% (n = 78) completed more than 75% of the attitudes toward breast-feeding scale and Loevinger's Sentence Completion Test and are included in these analyses. Mean age at entry was 17.8 +/- 1.5 years (range, 14.3 to 21.8 years). Mean gestational age at enrollment was 21.2 +/- 11.6 weeks (range, 4 to 41 weeks). Of the 78 participants, 12% (n = 9) were at the preconformist, 85% (n = 66) at the conformist, and 4% (n = 3) at the postconformist level of ego development as determined by the Sentence Completion Test. Attitudes toward breast-feeding, intention to breast-feed, breast-feeding in the hospital, and breast-feeding at 2 weeks postpartum were not significantly associated with adolescents' stages of ego development. Almost three fourths of the adolescents intended to breast-feed, and 85% tried breast-feeding in the hospital. A total of 97% (56 of 58) of those who intended to breast-feed tried breast-feeding in the hospital compared with 40% (4 of 10) of those who did not intend to breast-feed (P < .0001). At 2 weeks postpartum, 58% of the participants were still breast-feeding. Of those participants who intended to breast-feed, 67% (39 of 58) were breast-feeding at 2 weeks postpartum compared with 10% (1 of 10) who did not intend to breast-feed (P = .001). The mean breast-feeding attitude score was 53.7 +/- 11.6 (range, 25 to 72). The mean breast-feeding attitude score was higher for those who intended to breast-feed than for those who intended to formula-feed (P = .009), but the score was not associated with breast-feeding in the hospital or at 2 weeks postpartum. CONCLUSION: Adolescent mothers were predominantly in ego stages 4 and 5, the conformist level. Because ego development was not associated with outcome measures in this study, ego development may not be a crucial factor when designing interventions to facilitate breast-feeding among adolescents. Attitudes toward breast-feeding were associated with the intention to breast-feed but not behaviors; the intention to breast-feed was significantly associated with breast-feeding behaviors.


Assuntos
Comportamento do Adolescente , Alimentação com Mamadeira/psicologia , Aleitamento Materno/psicologia , Comportamento de Escolha , Ego , Mães/psicologia , Gravidez na Adolescência/psicologia , Psicologia do Adolescente , Adolescente , Adulto , Atitude Frente a Saúde , Feminino , Conhecimentos, Atitudes e Prática em Saúde , Humanos , Motivação , Gravidez , Estudos Prospectivos , Inquéritos e Questionários
18.
J Biol Chem ; 274(12): 7803-15, 1999 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-10075672

RESUMO

Human cystic fibrosis transmembrane conductance regulator gene (CFTR) transcription is tightly regulated by nucleotide sequences upstream of the initiator sequences. Our studies of human CFTR transcription focus on identifying transcription factors bound to an inverted CCAAT consensus or "Y-box element." The human homeodomain CCAAT displacement protein/cut homolog (CDP/cut) can bind to the Y-box element through a cut repeat and homeobox. Analysis of stably transfected cell lines with wild-type and mutant human CFTR-directed reporter genes demonstrates that human histone acetyltransferase GCN5 and transcription factor ATF-1 can potentiate CFTR transcription through the Y-box element. We have found 1) that human CDP/cut acts as a repressor of CFTR transcription through the Y-box element by competing for the sites of transactivators hGCN5 and ATF-1; 2) that the ability of CDP/cut to repress activities of hGCN5 and ATF-1 activity is contingent on the amount of CDP/cut expression; 3) that histone acetylation may have a role in the regulation of gene transcription by altering the accessibility of the CFTR Y-box for sequence-specific transcription factors; 4) that trichostatin A, an inhibitor of histone deacetylase activity, activates transcription of CFTR through the Y-box element; 5) that the inhibition of histone deacetylase activity leads to an alteration of local chromatin structure requiring an intact Y-box sequence in CFTR; 6) that immunocomplexes of CDP/cut possess an associated histone deacetylase activity; 7) that the carboxyl region of CDP/cut, responsible for the transcriptional repressor function, interacts with the histone deacetylase, HDAC1. We propose that CFTR transcription may be regulated through interactions with factors directing the modification of chromatin and requires the conservation of the inverted CCAAT (Y-box) element of the CFTR promoter.


Assuntos
Regulador de Condutância Transmembrana em Fibrose Cística/genética , Proteínas de Ligação a DNA , Histona Desacetilases/metabolismo , Proteínas de Homeodomínio/fisiologia , Proteínas Nucleares/fisiologia , Proteínas Repressoras/fisiologia , Transcrição Gênica , Fator 1 Ativador da Transcrição , Sequência de Bases , Proteínas de Ciclo Celular , Desoxirribonuclease I/metabolismo , Relação Dose-Resposta a Droga , Genes Reguladores , Histona Acetiltransferases , Humanos , Dados de Sequência Molecular , Regiões Promotoras Genéticas , Transativadores/metabolismo , Fatores de Transcrição/metabolismo , Ativação Transcricional , Transfecção , Fatores de Transcrição de p300-CBP
19.
J Pediatr Adolesc Gynecol ; 11(3): 139-41, 1998 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-9704304

RESUMO

STUDY OBJECTIVE: The purpose of this study was to determine the rate of unknown and nondisclosed pregnancies identified from a preoperative protocol for pregnancy testing of adolescents. DESIGN: A protocol was developed for pregnancy testing of all 12-21-year-old females presenting to the day surgery unit (DSU) at a large children's hospital. The charts of all patients identified with a positive urine ICON II human chorionic gonadotropin (uhCG) assay result were reviewed for demographic data, presurgical and postsurgical diagnosis, and proposed and actual procedure performed. Adolescents were asked the date of their last menstrual period (LMP), whether they were sexually active (SA) (engaged in vaginal intercourse), and whether they might be pregnant, and a uhCG was performed. SETTING: DSU at a large children's hospital in Boston, Massachusetts. PARTICIPANTS: All 12-21-year-old females presenting to DSU. MAIN OUTCOME MEASURES: Disclosure of sexual activity, date of LMP, and any possibility of pregnancy. The initial decision (continuation, abortion, or undecided) at the time of identification of the positive uhCG, compliance with follow-up referral appointments, outcome of the pregnancy, and subsequent choice of contraception were also documented. RESULTS: A total of 801 adolescent girls presented to the DSU for a surgical procedure between October 1994 and July 1996 and had a uhCG. Six of the 801 girls had a positive uhCG; 4 of 801 (0.49%) were pregnant. The remaining two had false-positive uhCG tests associated with ovarian failure and elevated gonadotropins. An LMP was recorded for the four pregnant patients, but only two patients were able to identify an exact date. SA was admitted by two of four and denied by the other two. One of the two who disclosed SA admitted to the possibility of being pregnant in response to the question, the other denied the possibility of pregnancy. The two who denied SA also failed to disclose the possibility of pregnancy. After disclosure of a positive uhCG, the surgical procedure was postponed in all four individuals. CONCLUSIONS: A routine preoperative uhCG testing program identified 4 of 801 (0.49%) patients with previously undiagnosed pregnancy. The current protocol has contributed to enhanced care and identifies pregnant adolescents who need counseling before surgical procedures are performed.


Assuntos
Programas de Rastreamento/métodos , Testes de Gravidez , Gravidez na Adolescência , Aborto Induzido , Adolescente , Adulto , Gonadotropina Coriônica/urina , Feminino , Procedimentos Cirúrgicos em Ginecologia , Humanos , Gravidez , Cuidados Pré-Operatórios
20.
Brain Res ; 790(1-2): 264-9, 1998 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-9593931

RESUMO

The neuroprotective effects of lowering body temperature have been well documented in various models of neuronal injury. The present study investigated the effects a lower ambient or core body temperature would have on damage to striatal dopamine (DA) neurons produced by 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP). Mice received systemic MPTP treatment at two different temperatures, 4 degrees C and 22 degrees C. MPTP-treated mice maintained at 4 degrees C demonstrated (1) a greater hypothermic response, (2) a significant reduction in striatal DA content and tyrosine hydroxylase (TH) activity, and (3) significantly greater striatal 1-methyl-4-phenylpyridinium (MPP+) levels, as compared to mice dosed with MPTP at room temperature. Parallel studies with methamphetamine (METH) were conducted since temperature appears to play a pivotal role in the mediation of damage to DA neurons by this CNS stimulant in rodents. As previously reported, METH-induced hyperthermia and the subsequent loss of striatal DA content were attenuated in animals dosed at 4 degrees C. We also evaluated the effects a hypothermic state induced by pharmacological agents would have on striatal neurochemistry and MPP+ levels following MPTP treatment. Concurrent administration of MK-801 or 8-OHDPAT increased the striatal MPP+ levels following MPTP treatment. However, only 8-OHDPAT potentiated the MPTP-induced decrements of striatal DA content and TH activity; MK-801 did not affect MPTP decreases in these striatal markers of dopaminergic damage. Altogether, these findings indicate that temperature has a profound effect on striatal MPP+ levels and MPTP-induced damage to DA neurons in mice.


Assuntos
1-Metil-4-fenilpiridínio/toxicidade , Temperatura Corporal/efeitos dos fármacos , Corpo Estriado/metabolismo , Dopaminérgicos/toxicidade , Intoxicação por MPTP , 1-Metil-4-Fenil-1,2,3,6-Tetra-Hidropiridina/farmacocinética , 1-Metil-4-fenilpiridínio/farmacocinética , 8-Hidroxi-2-(di-n-propilamino)tetralina/farmacologia , Animais , Corpo Estriado/citologia , Maleato de Dizocilpina/farmacologia , Dopamina/metabolismo , Dopaminérgicos/farmacocinética , Antagonistas de Aminoácidos Excitatórios/farmacologia , Metanfetamina/farmacologia , Camundongos , Degeneração Neural/induzido quimicamente , Degeneração Neural/metabolismo , Neurônios/química , Neurônios/enzimologia , Neurotoxinas/farmacocinética , Agonistas do Receptor de Serotonina/farmacologia , Tirosina 3-Mono-Oxigenase/metabolismo
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