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1.
Neuropharmacology ; 246: 109832, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38176535

RESUMO

Memory reconsolidation is a process by which labile drug memories are restabilized in long-term memory stores, permitting their enduring control over drug-seeking behaviors. In the present study, we investigated the involvement of the dorsal raphé nuclei (DRN) in cocaine-memory reconsolidation. Sprague-Dawley rats (male, female) were trained to self-administer cocaine in a distinct environmental context to establish contextual drug memories. They then received extinction training in a different context. Next, the rats were re-exposed to the cocaine-predictive context for 15 min to reactivate their cocaine memories or remained in their home cages (no-reactivation control). Memory reactivation was sufficient to increase c-Fos expression, an index of neuronal activation, in the DRN, but not in the median raphé nuclei, during reconsolidation, compared to no reactivation. To determine whether DRN neuronal activity was necessary for cocaine-memory reconsolidation, rats received intra-DRN baclofen plus muscimol (BM; GABAB/A agonists) or vehicle microinfusions immediately after or 6 h after a memory reactivation session conducted with or without lever access. The effects of DRN functional inactivation on long-term memory strength, as indicated by the magnitude of context-induced cocaine seeking, were assessed 72 h later. Intra-DRN BM treatment immediately after memory reactivation with or without lever access attenuated subsequent context-induced cocaine-seeking behavior, independent of sex. Conversely, BM treatment in the adjacent periaqueductal gray (PAG) immediately after memory reactivation, or BM treatment in the DRN 6 h after memory reactivation, did not alter responding. Together, these findings indicate that the DRN plays a requisite role in maintaining cocaine-memory strength during reconsolidation.


Assuntos
Cocaína , Núcleo Dorsal da Rafe , Feminino , Ratos , Masculino , Animais , Ratos Sprague-Dawley , Memória , Extinção Psicológica , Cocaína/farmacologia
2.
Braz J Biol ; 83: e275539, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37878961

RESUMO

The search for healthy foods has attracted the industry's attention to developing products that use natural ingredients, including natural antioxidants. Antioxidants act as free radicals or oxygen scavengers, inhibiting lipid oxidation and adversely affecting meat products' sensory and nutritional quality. Several synthetic antioxidants have been used in the meat industry; however, studies point to health risks related to their consumption. Such fact drives research into natural antioxidants extracted from grains, oilseeds, spices, fruits, and vegetables, which may have a health-promoting effect. This manuscript evaluates the effectiveness of several natural antioxidants in improving the quality and shelf life of chicken meat products during processing, storage, and distribution. The potential effects of natural antioxidants widely used in chicken products are also discussed. It can be concluded that these natural antioxidants are possible substitutes for synthetic ones. However, their use can affect the product's characteristics.


Assuntos
Antioxidantes , Produtos da Carne , Animais , Antioxidantes/farmacologia , Galinhas , Carne/análise , Produtos da Carne/análise , Extratos Vegetais/farmacologia
3.
Braz J Biol ; 84: e255440, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35584456

RESUMO

Tilapia has high-temperature tolerance, can breed in captivity, grow fast, and have excellent cost-benefit. Because of these characteristics, this species is of great interest in aquaculture and, currently, the most produced fish in Brazil. However, by increasing tilapia production, there was also a rise in the amount of organic waste, mainly from filleting, which discards 70% of waste. There are many studies on collagen extraction from tilapia skin as an alternative to reduce these residues and add commercial value. In this work, the extraction of protein concentrate was tested using an acid protocol, in which the tilapia skins underwent a pre-treatment in an acid medium and saline precipitation, with variations in time and concentration. After its extraction, the skin was evaluated for ash, moisture, protein, solubility, and pH. The protein concentrate obtained showed low ash contents, and the humidity is within those presented by the literature. The protein concentrate showed levels from 68.73 to 80.58% of protein and a low solubility between 4.03 to 6.93%. In conclusion, acid extraction is a possible means of collagen extraction, and tilapia skin is a good alternative to reuse waste generated in the fish industry.


Assuntos
Ciclídeos , Animais , Colágeno/química , Meios de Cultura , Temperatura Alta , Solubilidade
4.
Osteoporos Int ; 33(4): 791-806, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-34590158

RESUMO

High-resolution peripheral quantitative computed tomography (HR-pQCT) is a powerful tool to assess bone health. To determine how an individual's or population of interest's HR-pQCT outcomes compare to expected, reference data are required. This study provides reference data for HR-pQCT measures acquired in a population of White adults. PURPOSE: To provide age- and sex-specific reference data for high-resolution peripheral quantitative computed tomography (HR-pQCT) measures of the distal and diaphyseal radius and tibia acquired using a second-generation scanner and percent-of-length offsets proximal from the end of the bone. METHODS: Data were acquired in White adults (aged 18-80 years) living in the Midwest region of the USA. HR-pQCT scans were performed at the 4% distal radius, 30% diaphyseal radius, 7.3% distal tibia, and 30% diaphyseal tibia. Centile curves were fit to the data using the LMS approach. RESULTS: Scans of 867 females and 317 males were included. The fitted centile curves reveal HR-pQCT differences between ages, sexes, and sites. They also indicate differences when compared to data obtained by others using fixed length offsets. Excel-based calculators based on the current data were developed and are provided to enable computation of subject-specific percentiles, z-scores, and t-scores and to plot an individual's outcomes on the fitted curves. In addition, regression equations are provided to convert estimated failure load acquired with the conventional criteria utilized with first-generation scanners and those specifically developed for second-generation scanners. CONCLUSION: The current study provides unique data and resources. The combination of the reference data and calculators provide clinicians and investigators an ability to assess HR-pQCT outcomes in an individual or population of interest, when using the described scanning and analysis procedure. Ultimately, the expectation is these data will be expanded over time so the wealth of information HR-pQCT provides becomes increasingly interpretable and utilized.


Assuntos
Rádio (Anatomia) , Tíbia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Densidade Óssea , Osso e Ossos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Rádio (Anatomia)/diagnóstico por imagem , Tíbia/diagnóstico por imagem , Tomografia Computadorizada por Raios X/métodos , Adulto Jovem
5.
Environ Mol Mutagen ; 60(2): 100-121, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30536466

RESUMO

The interpretation and significance of DNA adduct data, their causal relationship to mutations, and their role in risk assessment have been debated for many years. An extended effort to identify key questions and collect relevant data to address them was focused on the ubiquitous low MW N7-alkyl/hydroxyalkylguanine adducts. Several academic, governmental, and industrial laboratories collaborated to gather new data aimed at better understanding the role and potential impact of these adducts in quantifiable genotoxic events (gene mutations/micronucleus). This review summarizes and evaluates the status of dose-response data for DNA adducts and mutations from recent experimental work with standard mutagenic agents and ethylene oxide and propylene oxide, and the importance for risk assessment. This body of evidence demonstrates that small N7-alkyl/hydroxyalkylguanine adducts are not pro-mutagenic and, therefore, adduct formation alone is not adequate evidence to support a mutagenic mode of action. Quantitative methods for dose-response analysis and derivation of thresholds, benchmark dose (BMD), or other points-of-departure (POD) for genotoxic events are now available. Integration of such analyses of genetox data is necessary to properly assess any role for DNA adducts in risk assessment. Regulatory acceptance and application of these insights remain key challenges that only the regulatory community can address by applying the many learnings from recent research. The necessary tools, such as BMDs and PODs, and the example datasets, are now available and sufficiently mature for use by the regulatory community. Environ. Mol. Mutagen. 60: 100-121, 2019. © 2018 The Authors. Environmental and Molecular Mutagenesis published by Wiley Periodicals, Inc. on behalf of Environmental Mutagen Society.


Assuntos
Adutos de DNA/genética , Mutagênese/efeitos dos fármacos , Mutação/efeitos dos fármacos , Adutos de DNA/química , Adutos de DNA/efeitos dos fármacos , Dano ao DNA/efeitos dos fármacos , Compostos de Epóxi/toxicidade , Óxido de Etileno/toxicidade , Humanos , Peso Molecular , Mutagênese/genética , Mutagênicos/toxicidade , Mutação/genética , Medição de Risco
6.
Leukemia ; 31(11): 2398-2406, 2017 11.
Artigo em Inglês | MEDLINE | ID: mdl-28804124

RESUMO

Chronic myeloid leukemia (CML)-study IV was designed to explore whether treatment with imatinib (IM) at 400 mg/day (n=400) could be optimized by doubling the dose (n=420), adding interferon (IFN) (n=430) or cytarabine (n=158) or using IM after IFN-failure (n=128). From July 2002 to March 2012, 1551 newly diagnosed patients in chronic phase were randomized into a 5-arm study. The study was powered to detect a survival difference of 5% at 5 years. After a median observation time of 9.5 years, 10-year overall survival was 82%, 10-year progression-free survival was 80% and 10-year relative survival was 92%. Survival between IM400 mg and any experimental arm was not different. In a multivariate analysis, risk group, major-route chromosomal aberrations, comorbidities, smoking and treatment center (academic vs other) influenced survival significantly, but not any form of treatment optimization. Patients reaching the molecular response milestones at 3, 6 and 12 months had a significant survival advantage. For responders, monotherapy with IM400 mg provides a close to normal life expectancy independent of the time to response. Survival is more determined by patients' and disease factors than by initial treatment selection. Although improvements are also needed for refractory disease, more life-time can currently be gained by carefully addressing non-CML determinants of survival.


Assuntos
Antineoplásicos/uso terapêutico , Mesilato de Imatinib/uso terapêutico , Leucemia Mielogênica Crônica BCR-ABL Positiva/tratamento farmacológico , Análise de Sobrevida , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Relação Dose-Resposta a Droga , Feminino , Transplante de Células-Tronco Hematopoéticas , Humanos , Leucemia Mielogênica Crônica BCR-ABL Positiva/terapia , Masculino , Pessoa de Meia-Idade , Adulto Jovem
7.
Neuropharmacology ; 123: 349-358, 2017 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-28549664

RESUMO

The basolateral amygdala (BLA) is a critical site for the reconsolidation of labile contextual cocaine memories following retrieval-induced reactivation/destabilization. Here, we examined whether glucocorticoid receptors (GR), which are abundant in the BLA, mediate this phenomenon. Rats were trained to lever press for cocaine reinforcement in a distinct environmental context, followed by extinction training in a different context. Rats were then briefly exposed to the cocaine-paired context (to elicit memory reactivation and reconsolidation) or their home cages (no reactivation control). Exposure to the cocaine-paired context elicited greater serum corticosterone concentrations than home cage stay. Interestingly, the GR antagonist, mifepristone (3-10 ng/hemisphere), administered into the BLA after memory reactivation produced a further, dose-dependent increase in serum corticosterone concentrations during the putative time of cocaine-memory reconsolidation but produced an inverted U-shaped dose-effect curve on subsequent cocaine-seeking behavior 72 h later. This effect was anatomically selective, dependent on memory reactivation (i.e., not observed after home cage exposure), and did not reflect protracted hyperactivity. However, the effect was also observed when mifepristone was administered after novelty stress that mimics drug context-induced hypothalamic-pituitary-adrenal (HPA) axis activation without explicit memory reactivation. Together, these findings suggest that, similar to explicit memory retrieval, a stressful event is sufficient to destabilize cocaine memories and permit their manipulation. Furthermore, BLA GR stimulation exerts inhibitory feedback upon HPA axis activation and thus suppresses cocaine-memory reconsolidation.


Assuntos
Cocaína/farmacologia , Memória/efeitos dos fármacos , Memória/fisiologia , Nootrópicos/farmacologia , Receptores de Glucocorticoides/metabolismo , Animais , Complexo Nuclear Basolateral da Amígdala/efeitos dos fármacos , Complexo Nuclear Basolateral da Amígdala/metabolismo , Transtornos Relacionados ao Uso de Cocaína/tratamento farmacológico , Transtornos Relacionados ao Uso de Cocaína/metabolismo , Corticosterona/sangue , Relação Dose-Resposta a Droga , Comportamento de Procura de Droga/efeitos dos fármacos , Comportamento de Procura de Droga/fisiologia , Antagonistas de Hormônios/farmacologia , Sistema Hipotálamo-Hipofisário/efeitos dos fármacos , Sistema Hipotálamo-Hipofisário/metabolismo , Masculino , Mifepristona/farmacologia , Atividade Motora/efeitos dos fármacos , Atividade Motora/fisiologia , Sistema Hipófise-Suprarrenal/efeitos dos fármacos , Sistema Hipófise-Suprarrenal/metabolismo , Ratos Sprague-Dawley , Receptores de Glucocorticoides/antagonistas & inibidores , Autoadministração
8.
Osteoporos Int ; 28(7): 2155-2165, 2017 07.
Artigo em Inglês | MEDLINE | ID: mdl-28396902

RESUMO

Physical activity benefits the skeleton, but there is contrasting evidence regarding whether benefits differ at different stages of growth. The current study demonstrates that physical activity should be encouraged at the earliest age possible and be continued into early adulthood to gain most skeletal benefits. INTRODUCTION: The current study explored physical activity-induced bone adaptation at different stages of somatic maturity by comparing side-to-side differences in midshaft humerus properties between male throwing athletes and controls. Throwers present an internally controlled model, while inclusion of control subjects removes normal arm dominance influences. METHODS: Throwing athletes (n = 90) and controls (n = 51) were categorized into maturity groups (pre, peri, post-early, post-mid, and post-late) based on estimated years from peak height velocity (<-2, -2 to 2, 2 to 4, 4 to 10, and >10 years). Side-to-side percent differences in midshaft humerus cortical volumetric bone mineral density (Ct.vBMD) and bone mineral content (Ct.BMC); total (Tt.Ar), medullary (Me.Ar), and cortical (Ct.Ar) areas; average cortical thickness (Ct.Th); and polar Strength Strain Index (SSIP) were assessed. RESULTS: Significant interactions between physical activity and maturity on side-to-side differences in Ct.BMC, Tt.Ar, Ct.Ar, Me.Ar, Ct.Th, and SSIP resulted from the following: (1) greater throwing-to-nonthrowing arm differences than dominant-to-nondominant arm differences in controls (all p < 0.05) and (2) throwing-to-nonthrowing arm differences in throwers being progressively greater across maturity groups (all p < 0.05). Regional analyses revealed greatest adaptation in medial and lateral sectors, particularly in the three post-maturity groups. Years throwing predicted 59% of the variance of the variance in throwing-to-nonthrowing arm difference in SSIP (p < 0.001). CONCLUSION: These data suggest that physical activity has skeletal benefits beginning prior to and continuing beyond somatic maturation and that a longer duration of exposure to physical activity has cumulative skeletal benefits. Thus, physical activity should be encouraged at the earliest age possible and be continued into early adulthood to optimize skeletal benefits.


Assuntos
Beisebol/fisiologia , Exercício Físico/fisiologia , Úmero/fisiologia , Absorciometria de Fóton/métodos , Adaptação Fisiológica/fisiologia , Adolescente , Antropometria/métodos , Densidade Óssea/fisiologia , Estudos de Casos e Controles , Criança , Humanos , Úmero/anatomia & histologia , Masculino , Puberdade/fisiologia , Tomografia Computadorizada por Raios X , Suporte de Carga/fisiologia , Adulto Jovem
9.
Cell Death Dis ; 6: e2011, 2015 Dec 03.
Artigo em Inglês | MEDLINE | ID: mdl-26633717

RESUMO

Serum response factor (SRF) is a transcription factor known to mediate phenotypic plasticity in smooth muscle cells (SMCs). Despite the critical role of this protein in mediating intestinal injury response, little is known about the mechanism through which SRF alters SMC behavior. Here, we provide compelling evidence for the involvement of SRF-dependent microRNAs (miRNAs) in the regulation of SMC apoptosis. We generated SMC-restricted Srf inducible knockout (KO) mice and observed both severe degeneration of SMCs and a significant decrease in the expression of apoptosis-associated miRNAs. The absence of these miRNAs was associated with overexpression of apoptotic proteins, and we observed a high level of SMC death and myopathy in the intestinal muscle layers. These data provide a compelling new model that implicates SMC degeneration via anti-apoptotic miRNA deficiency caused by lack of SRF in gastrointestinal motility disorders.


Assuntos
Mucosa Intestinal/metabolismo , MicroRNAs/metabolismo , Fator de Resposta Sérica/metabolismo , Animais , Apoptose , Diferenciação Celular , Proliferação de Células , Humanos , Intestinos/citologia , Intestinos/patologia , Camundongos , Miócitos de Músculo Liso , Transdução de Sinais
10.
J Musculoskelet Neuronal Interact ; 15(1): 83-94, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25730656

RESUMO

Activated Leukocyte Cell Adhesion Molecule (ALCAM/CD166), is expressed on osteoblasts (OB) and hematopoietic stem cells (HSC) residing in the hematopoietic niche, and may have important regulatory roles in bone formation. Because HSC numbers are reduced 77% in CD166(-/-) mice, we hypothesized that changes in bone phenotype and consequently the endosteal niche may partially be responsible for this alteration. Therefore, we investigated bone phenotype and OB function in CD166(-/-) mice. Although osteoclastic measures were not affected by loss of CD166, CD166(-/-) mice exhibited a modest increase in trabecular bone fraction (42%), and increases in osteoid deposition (72%), OB number (60%), and bone formation rate (152%). Cortical bone geometry was altered in CD166(-/-) mice resulting in up to 81% and 49% increases in stiffness and ultimate force, respectively. CD166(-/-) OB displayed elevated alkaline phosphatase (ALP) activity and mineralization, and increased mRNA expression of Fra 1, ALP, and osteocalcin. Overall, CD166(-/-) mice displayed modestly elevated trabecular bone volume fraction with increased OB numbers and deposition of osteoid, and increased OB differentiation in vitro, possibly suggesting more mature OB are secreting more osteoid. This may explain the decline in HSC number in vivo because immature OB are mainly responsible for hematopoiesis enhancing activity.


Assuntos
Molécula de Adesão de Leucócito Ativado/metabolismo , Osso e Ossos/fisiologia , Hematopoese/fisiologia , Osteoblastos/metabolismo , Absorciometria de Fóton , Animais , Fenômenos Biomecânicos , Diferenciação Celular/fisiologia , Feminino , Células-Tronco Hematopoéticas/citologia , Células-Tronco Hematopoéticas/metabolismo , Masculino , Camundongos , Camundongos Knockout , Osteoblastos/citologia , Osteogênese/fisiologia , Fenótipo , Reação em Cadeia da Polimerase em Tempo Real , Microtomografia por Raio-X
11.
Scand J Med Sci Sports ; 25(5): e442-50, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25438993

RESUMO

Although amateur sports have become increasingly competitive within recent decades, there are as yet few studies on the possible health risks for athletes. This study aims to determine the impact of ultra-endurance exercise-induced stress on the number and function of circulating hematopoietic progenitor cells (CPCs) and hematological, inflammatory, clinical, metabolic, and stress parameters in moderately trained amateur athletes. Following ultra-endurance exercise, there were significant increases in leukocytes, platelets, interleukin-6, fibrinogen, tissue enzymes, blood lactate, serum cortisol, and matrix metalloproteinase-9. Ultra-endurance exercise did not influence the number of CPCs but resulted in a highly significant decline of CPC functionality after the competition. Furthermore, Epstein-Barr virus was seen to be reactivated in one of seven athletes. The link between exercise-induced stress and decline of CPC functionality is supported by a negative correlation between cortisol and CPC function. We conclude that ultra-endurance exercise induces metabolic stress and an inflammatory response that affects not only mature hematopoietic cells but also the function of the immature hematopoietic stem and progenitor cell fraction, which make up the immune system and provide for regeneration.


Assuntos
Células-Tronco Hematopoéticas/fisiologia , Inflamação/etiologia , Condicionamento Físico Humano/efeitos adversos , Resistência Física , Estresse Fisiológico/fisiologia , Adulto , Ensaio de Unidades Formadoras de Colônias , Feminino , Fibrinogênio/metabolismo , Herpesvirus Humano 4/fisiologia , Humanos , Hidrocortisona/sangue , Inflamação/sangue , Interleucina-6/sangue , Ácido Láctico/sangue , Contagem de Leucócitos , Masculino , Metaloproteinase 9 da Matriz/sangue , Pessoa de Meia-Idade , Contagem de Plaquetas , Ativação Viral
12.
Mar Pollut Bull ; 64(8): 1596-613, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22721694

RESUMO

In view of increasing environmental awareness and biodiversity conservation, understanding the main forcing mechanism driving biogeochemical cycles in coral reefs and lagoon coastal areas is a priority. La Niña events cause unbalanced situations in the Equatorial Pacific and result in enhanced precipitation in South West Pacific coastal areas. We investigated the impact of heavy rainfalls during the 2008 La Niña event on the New Caledonia lagoon using a 3D coupled on-line hydrodynamic-biogeochemical model. Simulations and data showed that the whole lagoon was impacted by river inputs and stronger hydrodynamics, enhancing chlorophyll-a concentration by a factor between 1.7 and 1.9. The coupled model provided new insights into plume transport, highlighting that eastern plumes can be advected northwards or can reach the South West Lagoon, depending on the balance between regional, tide-induced, and wind-induced surface currents. It also provided a synoptic view of lagoon biogeochemical-hydrodynamic response, when remote sensing data are not available due to cloud coverage.


Assuntos
El Niño Oscilação Sul , Monitoramento Ambiental , Modelos Teóricos , Água do Mar/química , Água Doce/análise , Água Doce/química , Oceano Pacífico , Estações do Ano
13.
Osteoporos Int ; 23(12): 2775-83, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22258805

RESUMO

UNLABELLED: The proximal humerus is a common site for osteoporotic fracture. The current study demonstrates the rate of age-related decline in proximal humerus bone health. The data suggest aging is associated with considerable loss of bone mass, structural deterioration and reduced bone strength at the proximal humerus. INTRODUCTION: The proximal humerus is relatively under investigated despite being the fourth most common site for osteoporotic fracture. METHODS: A cross-sectional study was performed to assess age-related changes in dual-energy X-ray absorptiometry (DXA) and peripheral quantitative computed tomography (pQCT) properties of the proximal humerus in a cohort of 170 healthy, white males. RESULTS: Regression models estimated considerable age-related loss of DXA measured bone quantity at the proximal humerus, with areal bone mineral density modeled to decline by 29% (95% confidence interval [CI], 17.5-35.0%) in the 50 years between ages 30 and 80 years (p < 0.001). pQCT measures indicated aging was associated with progressive periosteal and endosteal expansion, with the later occurring more rapidly as indicated by age-related declines in cortical bone mass, area and thickness (all p < 0.01). The net result of the density, mass and structural changes was a 26% (95% CI, 13.5-38.0%) decline in pQCT estimated proximal humerus bone strength in the 50 years between ages 30 and 80 years (p < 0.001). CONCLUSION: Aging is associated with considerable declines in proximal humeral bone health which, when coupled with a traumatic event such as a fall, may contribute to osteoporotic fracture at this site.


Assuntos
Envelhecimento/fisiologia , Densidade Óssea/fisiologia , Úmero/fisiologia , Osteoporose/fisiopatologia , Absorciometria de Fóton , Adulto , Idoso , Idoso de 80 Anos ou mais , Antropometria , Estudos Transversais , Humanos , Cabeça do Úmero/diagnóstico por imagem , Cabeça do Úmero/fisiologia , Úmero/diagnóstico por imagem , Masculino , Pessoa de Meia-Idade , Osteoporose/diagnóstico por imagem , Tomografia Computadorizada por Raios X
14.
IEEE Trans Vis Comput Graph ; 18(12): 2159-68, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26357123

RESUMO

Room air flow and air exchange are important aspects for the design of energy-efficient buildings. As a result, simulations are increasingly used prior to construction to achieve an energy-efficient design. We present a visual analysis of air flow generated at building entrances, which uses a combination of revolving doors and air curtains. The resulting flow pattern is challenging because of two interacting flow patterns: On the one hand, the revolving door acts as a pump, on the other hand, the air curtain creates a layer of uniformly moving warm air between the interior of the building and the revolving door. Lagrangian coherent structures (LCS), which by definition are flow barriers, are the method of choice for visualizing the separation and recirculation behavior of warm and cold air flow. The extraction of LCS is based on the finite-time Lyapunov exponent (FTLE) and makes use of a ridge definition which is consistent with the concept of weak LCS. Both FTLE computation and ridge extraction are done in a robust and efficient way by making use of the fast Fourier transform for computing scale-space derivatives.

15.
J Fish Biol ; 77(7): 1459-87, 2010 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-21078013

RESUMO

In a microchromosome-carrying laboratory stock of the normally all-female Amazon molly Poecilia formosa triploid individuals were obtained, all of which spontaneously developed into males. A comparison of morphology of the external and internal insemination apparatus and the gonads, sperm ploidy and behaviour, to laboratory-bred F(1) hybrids revealed that the triploid P. formosa males, though producing mostly aneuploid sperm, are partly functional males that differ mainly in sperm maturation and sexual motivation from gonochoristic P. formosa males.


Assuntos
Comportamento Animal/fisiologia , Cromossomos/genética , Poecilia/anatomia & histologia , Poecilia/fisiologia , Testículo/crescimento & desenvolvimento , Triploidia , Animais , Clonagem de Organismos , DNA/análise , Feminino , Masculino , Poecilia/genética , Poecilia/crescimento & desenvolvimento , Caracteres Sexuais , Comportamento Sexual Animal/fisiologia , Testículo/química , Testículo/citologia
17.
Neuroscience ; 171(3): 830-9, 2010 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-20870011

RESUMO

The ventral hippocampus (VH) plays critical roles in cue-induced and cocaine-primed reinstatement of cocaine seeking [Rogers JL, See RE (2007) Neurobiol Learn Mem 87:688-692]. Subregions of the VH make distinct projections to elements of the brain relapse circuitry that mediate drug context-induced reinstatement. Thus, the VH may also critically contribute to this form of cocaine seeking in a subregion-specific manner. Accordingly, this study evaluated the hypothesis that functional inactivation of the ventral hippocampus proper (VHp)-but not of the dentate gyrus (DG)-impairs cocaine seeking elicited by re-exposure to a drug-paired environmental context. Rats were trained to lever press for un-signaled i.v. cocaine infusions (0.15 mg/infusion) in a distinct environmental context (cocaine-paired context) followed by extinction training in a distinctly different context (extinction context). Subsequently, cocaine-seeking behavior (i.e., non-reinforced active lever responding) was assessed in either the previously cocaine-paired context or the extinction context. Rats received bilateral microinfusions of the GABA agonist cocktail, baclofen+muscimol (BM: 1.0/.01 mM), or vehicle into the VHp, DG, or the posterior dorsal hippocampus (pDH; extra-VH control) immediately before each test session. Exposure to the previously cocaine-paired context, but not the extinction context, reinstated extinguished cocaine-seeking behavior following vehicle pretreatment. BM pretreatment administered into the VHp, but not the DG or pDH, significantly attenuated drug context-induced cocaine seeking. These results indicate that the VH contributes to drug context-induced cocaine seeking in a subregion-specific manner, with the functional integrity of the VHp being necessary for memory or motivational aspects of drug-paired environmental stimuli that sustain stimulus control over goal-directed behavior.


Assuntos
Comportamento Animal/efeitos dos fármacos , Transtornos Relacionados ao Uso de Cocaína/fisiopatologia , Cocaína/farmacologia , Hipocampo/efeitos dos fármacos , Animais , Comportamento Animal/fisiologia , Transtornos Relacionados ao Uso de Cocaína/patologia , Inibidores da Captação de Dopamina/farmacologia , Hipocampo/fisiopatologia , Masculino , Ratos , Ratos Sprague-Dawley , Recompensa
18.
Placenta ; 30(6): 507-15, 2009 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19362735

RESUMO

Materno-fetal IgG transfer in the mature human placenta involves transport across the syncytiotrophoblast (STB) and fetal endothelial cell layer. The MHC class I-related Fc gamma-receptor (hFcRn) localized in STB as well as in endothelial cells is involved in overall IgG transfer from the maternal into the fetal circulation. Functional hFcRn is a heterodimer of a transmembrane alpha-chain and beta2-microglobulin. To establish the basis for future studies to unravel the mechanism of IgG transport in STB, we investigated hFcRn alpha-chain and beta2-microglobulin expression in cytotrophoblasts (CTB) isolated from human term placentae and cultured in vitro under conditions where differentiation into multinuclear STB takes place (>or=48 h). Northern blot analysis demonstrated up-regulation of alpha-chain mRNA after 48 h of in vitro cultivation. Likewise, hFcRn alpha-chain and beta2-microglobulin were at the limit of detection by immunofluorescence microscopy in CTB immediately after isolation, but their expression increased upon STB formation. hFcRn alpha-chain co-localized with beta2-microglobulin in multinuclear STB and formed a functional, i.e. low pH IgG binding, receptor as shown by affinity isolation. The in vitro differentiated STB exhibited specific, low pH-dependent IgG binding to the plasma membrane. In conclusion, these cultures can now be applied to study the role of hFcRn in IgG transport and trafficking in STB cultures in vitro.


Assuntos
Antígenos de Histocompatibilidade Classe I/genética , Receptores Fc/genética , Trofoblastos/metabolismo , Diferenciação Celular/genética , Membrana Celular/metabolismo , Separação Celular , Células Cultivadas , Feminino , Expressão Gênica , Antígenos de Histocompatibilidade Classe I/metabolismo , Humanos , Concentração de Íons de Hidrogênio , Imunoglobulina G/metabolismo , Troca Materno-Fetal/imunologia , Gravidez , Ligação Proteica , Transporte Proteico/imunologia , Receptores Fc/metabolismo , Trofoblastos/fisiologia , Microglobulina beta-2/metabolismo
19.
Leukemia ; 23(1): 153-61, 2009 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-18818699

RESUMO

Lymphoplasmacytic lymphoma (LPL) is an indolent lymphoma with moderate sensitivity to conventional chemotherapy. This study investigated whether the addition of rituximab to standard chemotherapy improves treatment outcome in LPL and the subgroup of LPL patients fulfilling the criteria of Waldenstroem's macroglobulinemia (WM). A total of 69 patients with previously untreated LPL were enrolled into the trial; 64 patients were evaluable for treatment outcome. In all, 48 of the 64 LPL patients fulfilled the criteria of WM. Patients were randomly assigned to R-CHOP (rituximab, cyclophosphamide, doxorubicin, vincristine and prednisone, n=34) or CHOP (n=30). R-CHOP resulted in significantly higher overall response (OR) rate (94 vs 67%, P=0.0085) in the LPL patients and in the WM subgroup (91 vs 60%, P=0.0188). With a median observation time of 42 months, R-CHOP induced a significantly longer time to treatment failure (TTF) with a median of 63 months for R-CHOP vs 22 months in the CHOP arm in the LPL patients (P=0.0033) and in the WM subgroup (P=0.0241). There was no major difference of treatment-associated toxicity between both treatment groups. These data indicate that the addition of rituximab to front-line chemotherapy improves treatment outcome in patients with LPL or WM.


Assuntos
Anticorpos Monoclonais/administração & dosagem , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Macroglobulinemia de Waldenstrom/tratamento farmacológico , Adulto , Idoso , Anticorpos Monoclonais/toxicidade , Anticorpos Monoclonais Murinos , Ciclofosfamida/uso terapêutico , Intervalo Livre de Doença , Doxorrubicina/uso terapêutico , Humanos , Pessoa de Meia-Idade , Prednisona/uso terapêutico , Indução de Remissão , Rituximab , Resultado do Tratamento , Vincristina/uso terapêutico
20.
Osteoporos Int ; 19(9): 1331-41, 2008 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-18385919

RESUMO

INTRODUCTION: Strontium ranelate (SrR) is suggested to function as a dual-acting agent in the treatment of postmenopausal osteoporosis with anti-resorptive and anabolic skeletal benefits. We evaluated the effects of SrR on the skeleton in ovariectomized (OVX) rats and evaluated the influence of dietary calcium. METHODS: Three-month old virgin female rats underwent ovariectomy (OVX, n = 50) or SHAM surgery (SHAM, n = 10). Four weeks post-surgery, rats were treated daily by oral gavage with distilled water (10 ml/kg/day) or SrR (25 or 150 mg/kg/day) for 90 days. Separate groups of animals for each dose of SrR were fed a low (0.1%) or normal (1.19%) calcium (Ca) diet. Static and dynamic histomorphometry, DXA, mu-CT, mechanical testing, and serum and skeletal concentrations of strontium were assessed. RESULTS: SrR at doses of 25 and 150 mg/kg/day did not increase bone formation on trabecular or periosteal bone surfaces, and failed to inhibit bone resorption of trabecular bone regardless of Ca intake. There were no improvements in bone mass, volume or strength with either dose of SrR given normal Ca. CONCLUSION: These findings demonstrate that SrR at dosages of 25 and 150 mg/kg/day did not stimulate an anabolic bone response, and failed to improve the bone biomechanical properties of OVX rats.


Assuntos
Conservadores da Densidade Óssea/farmacologia , Compostos Organometálicos/farmacologia , Osteogênese/efeitos dos fármacos , Tiofenos/farmacologia , Absorciometria de Fóton , Animais , Reabsorção Óssea/fisiopatologia , Reabsorção Óssea/prevenção & controle , Osso e Ossos/metabolismo , Cálcio da Dieta/farmacologia , Relação Dose-Resposta a Droga , Avaliação Pré-Clínica de Medicamentos/métodos , Feminino , Fêmur/efeitos dos fármacos , Fêmur/fisiopatologia , Vértebras Lombares/efeitos dos fármacos , Vértebras Lombares/fisiopatologia , Compostos Organometálicos/farmacocinética , Ovariectomia , Ratos , Ratos Sprague-Dawley , Estresse Mecânico , Estrôncio/sangue , Tiofenos/farmacocinética
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