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1.
Accid Anal Prev ; 144: 105595, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32534288

RESUMO

There is extensive literature into the mechanisms of injury in traffic crashes involving vulnerable road users (VRUs), but little research into the social or psychological factors in causation in these crash types. Attitudes and emotional associations can affect how people attend to objects in their visual environment and physical approach/avoidance responses, but few studies have extended these approaches into the road safety domain. Existing driving simulator studies of driver-bicyclist interactions have focused on driver behavior but not underlying attitudes and their effect on safety-related behaviors. This research explored the impact of implicit and explicit attitudes on drivers' behavior in interactions with bicyclists. In a driving simulator, various objective measures of safety (e.g., speed, passing distance, crash occurrence) were collected in an overtaking scenario. Participants' self-reported attitudes about driving and bicyclists were collected via survey instrument, along with an online test of subconscious attitudes called an Implicit Association Test, developed to examine preference between drivers and bicyclists. Importantly, this study examined not only distance, but duration and speed during overtaking. Results demonstrate that conscious attitudes affect how quickly and closely drivers overtake bicyclists. Participants who hold negative attitudes about bicyclists as a legitimate road user group passed significantly faster, while people with concerns about their knowledge or judgment about overtaking a bicyclist passed further and more slowly. Drivers self-identification as a bicyclist predicted higher passing speeds, while respondents who bicycle weekly drove closer but more slowly to the simulated bicyclist. These behaviors did not significantly differ based on the measure of implicit attitudes. The results of this study provide potential avenues for infrastructure and education interventions to improve pedestrian and bicyclist safety. Additionally, pairing driving simulator behavior with attitudinal measures represents a significant methodological contribution.


Assuntos
Condução de Veículo/psicologia , Ciclismo/psicologia , Acidentes de Trânsito/prevenção & controle , Adulto , Simulação por Computador , Feminino , Humanos , Masculino , Autorrelato
2.
Transplant Proc ; 50(8): 2506-2508, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30316387

RESUMO

BACKGROUND: Numerous studies have shown that osteoporosis is common in kidney transplant recipients. However, the change in bone mineral density after kidney transplantation (KT) is not fully understood. METHODS: Thirty-nine kidney transplant recipients with bone densitometry at pretransplant and 24 months after KT were reviewed. RESULTS: The recipients' median age (44.5 ± 10.7 years) and dialysis duration before KT (4.2 ± 3.4 years) were recorded. The T-scores of the lumbar spine and femur neck at 24 months after KT were positively associated with the respective pretransplant T-score (P < .001 in the lumbar spine and P < .001 in the femur neck). However, the T-score after KT did not show significant change (P = .680 in lumbar spine, P = .093 in femur neck). Changes in the T-scores of the lumbar spine and femur neck over 24 months (delta T-score) were negatively associated with the respective pretransplant T-scores (P = .001 in lumbar spine, P = .026 in femur neck). Changes in the T-scores of the lumbar spine and femur neck over 24 months (delta T-score) were also associated with the pretransplant T-scores after the adjustment of other variables. CONCLUSION: The change of bone mineral density was related with pretransplant bone mineral density. Careful follow-up of bone densitometry for KT recipients was needed.


Assuntos
Densidade Óssea/fisiologia , Transplante de Rim/efeitos adversos , Osteoporose/etiologia , Absorciometria de Fóton , Adulto , Feminino , Humanos , Vértebras Lombares , Masculino , Pessoa de Meia-Idade , Osteoporose/epidemiologia
3.
Transplant Proc ; 50(8): 2572-2574, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30316401

RESUMO

Besides the initial description of IgG4-related pancreatic disease, other sites are now commonly involved. However, occurrence of IgG4-related disease is rare in organ transplanted patients. A 57-year-old man who received a kidney transplantation presented with recurrent dyspnea on exertion. A computed tomography scan of the chest revealed bilateral interlobular septal thickening and multiple tubular and branching small nodular lesions in the right upper lobe, and mass-like consolidation of the left middle lobe. Despite no elevation of serum IgG4 level, a percutaneous core needle biopsy on consolidative mass showed interstitial fibrosis and infiltration of IgG4-positive plasma cells to be more than > 20 per high power field. After treatment with glucocorticoids and rituximab, the consolidative mass of the left middle lobe disappeared.


Assuntos
Doença Relacionada a Imunoglobulina G4/complicações , Transplante de Rim/efeitos adversos , Doenças Pulmonares Intersticiais/complicações , Glucocorticoides/uso terapêutico , Humanos , Doença Relacionada a Imunoglobulina G4/tratamento farmacológico , Fatores Imunológicos/uso terapêutico , Doenças Pulmonares Intersticiais/tratamento farmacológico , Masculino , Pessoa de Meia-Idade , Rituximab/uso terapêutico , Tomografia Computadorizada por Raios X
4.
Orthod Craniofac Res ; 2018 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-29863289

RESUMO

OBJECTIVES: Craniofacial assessments often involve three-dimensional facial imaging using an expensive camera with 6 SLR lenses to analyse the positions and relations of anatomic landmarks. Recently, a 3D small-format, handheld camera was developed; however, the accuracy and reliability of this system are largely unknown. The purpose of this study was to evaluate the accuracy and reliability of this system. MATERIALS & METHODS: A total of 30 sets of evaluations were completed by 2 examiners on 5 human subjects, using 3 different methods: direct callipers, 3D handheld camera and conventional tripod 3D camera images. Each evaluation included 29 anthropometric landmarks that were used as reference points for facial analysis. Two examiners marked the landmarks directly on the faces and measured linear distances using the 3 measurement methods. RESULTS: Accuracy analysis was performed for handheld vs direct calliper vs conventional camera measurements. Each of these analyses yielded a grand mean of correlation coefficients of .98. Bias measurements revealed that the handheld and conventional camera methods yielded larger measurements than direct callipers (with a mean difference of 1.74, 1.56 mm, respectively, for rater 1 and 0.94, 1.02 mm, respectively, for rater 2). When compared to one another, both the handheld camera and the conventional camera methods yielded similar values for most measurements, with the average overall difference between these modalities of 0.03 mm for rater 1 and 0.07 mm for rater 2. CONCLUSIONS: The 3D handheld camera showed high accuracy and reliability in comparison with traditional models, indicating that this system may provide a useful tool in craniofacial anthropometry.

5.
Transplant Proc ; 48(3): 884-6, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-27234758

RESUMO

BACKGROUND: Arterial stiffness is associated with cardiovascular disease in end-stage renal disease (ESRD) and after kidney transplantation. We examined how kidney transplantation influences brachial-ankle pulse-wave velocity (baPWV) in ESRD patients. METHODS: The prospective observational study enrolled 67 patients who underwent successful kidney transplantation. Serial baPWV and biochemical parameters were measured before surgery and 6 months, 1 year, and 2 years after transplantation. RESULTS: baPWV prior to kidney transplantation and 6 months, 1 year, and 2 years after transplantation was 1533 ± 261 cm/s, 1417 ± 254 cm/s, 1414 ± 285 cm/s, and 1384 ± 233 cm/s, respectively. baPWV and biochemical parameters including alkaline phosphatase, intact parathyroid hormone, and 1,25 hydroxyvitamin D improved significantly at 6 months (P < .05), but there were no changes between 6 months and 2 years after transplantation. The majority of patients (73%) improved, whereas the remainder showed progression of baPWV after transplantation. Sixty-three percent of all kidney transplantation patients displayed higher baPWV than the healthy control subjects at 6 months after transplant. CONCLUSIONS: In the majority of patients, baPWV improved soon after kidney transplantation but overall remained higher than in the generally healthy population.


Assuntos
Artéria Braquial/fisiopatologia , Falência Renal Crônica/cirurgia , Transplante de Rim , Recuperação de Função Fisiológica , Rigidez Vascular/fisiologia , Progressão da Doença , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Pletismografia , Estudos Prospectivos , Análise de Onda de Pulso , Fatores de Tempo
6.
Transplant Proc ; 48(3): 897-9, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-27234762

RESUMO

BACKGROUND: Numerous studies have shown that vitamin D deficiency is common in end stage renal disease patients. However, change of the vitamin D deficiency after kidney transplantation is not fully understood. METHODS: Twenty-five kidney transplant (KT) recipients with serum 25-hydroxyvitamin D (25D) level, 1,25-dihydroxyvitamin D (1,25D) level, parathyroid hormone (PTH) level before and 6, 12, and 24 months after transplantation were reviewed. RESULTS: Serum PTH level and 1,25D level showed significant changes at 6 months after transplantation, but did not show further change at 12 months. 25D level did not increase within 6 months after transplantation. However, 25D level showed gradual increase after 6 months. The proportion of recipients with 25D deficiency (<10 ng/mL) was 68%, 40%, and 28% before, 12 months after, and 24 months after transplantation, respectively. Patients with vitamin D deficiency at 24 month were younger at transplantation (37.7 ± 9.6 y vs 48.2 ± 8.0 y; P = .029) and had lower 25D level before transplantation (7.96 ± 1.74 ng/mL vs 10.59 ± 4.35 ng/mL; P = .041). CONCLUSIONS: 25D deficiency is persistent in almost kidney transplant recipients even 12 months after transplantation, although serum PTH levels decrease and serum 25D levels increase after transplantation.


Assuntos
Falência Renal Crônica/cirurgia , Transplante de Rim/efeitos adversos , Hormônio Paratireóideo/sangue , Complicações Pós-Operatórias , Deficiência de Vitamina D/sangue , Vitamina D/análogos & derivados , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Vitamina D/sangue , Deficiência de Vitamina D/etiologia
7.
Oncogene ; 35(17): 2145-55, 2016 04 28.
Artigo em Inglês | MEDLINE | ID: mdl-26300004

RESUMO

UNLABELLED: Fibroblast growth factor-inducible 14 (Fn14; TNFRSF12A) is the cell surface receptor for the tumor necrosis factor (TNF) family member TNF-like weak inducer of apoptosis (TWEAK). The Fn14 gene is normally expressed at low levels in healthy tissues but expression is significantly increased after tissue injury and in many solid tumor types, including glioblastoma (GB; formerly referred to as 'GB multiforme'). GB is the most common and aggressive primary malignant brain tumor and the current standard-of-care therapeutic regimen has a relatively small impact on patient survival, primarily because glioma cells have an inherent propensity to invade into normal brain parenchyma, which invariably leads to tumor recurrence and patient death. Despite major, concerted efforts to find new treatments, a new GB therapeutic that improves survival has not been introduced since 2005. In this review article, we summarize studies indicating that (i) Fn14 gene expression is low in normal brain tissue but is upregulated in advanced brain cancers and, in particular, in GB tumors exhibiting the mesenchymal molecular subtype; (ii) Fn14 expression can be detected in glioma cells residing in both the tumor core and invasive rim regions, with the maximal levels found in the invading glioma cells located within normal brain tissue; and (iii) TWEAK: Fn14 engagement as well as Fn14 overexpression can stimulate glioma cell migration, invasion and resistance to chemotherapeutic agents in vitro. We also discuss two new therapeutic platforms that are currently in development that leverage Fn14 overexpression in GB tumors as a way to deliver cytotoxic agents to the glioma cells remaining after surgical resection while sparing normal healthy brain cells.


Assuntos
Glioblastoma/tratamento farmacológico , Glioblastoma/genética , Receptores do Fator de Necrose Tumoral/genética , Fatores de Necrose Tumoral/genética , Apoptose/genética , Movimento Celular/genética , Citocina TWEAK , Resistencia a Medicamentos Antineoplásicos/genética , Regulação Neoplásica da Expressão Gênica , Glioblastoma/patologia , Glioblastoma/cirurgia , Humanos , Invasividade Neoplásica/genética , Receptores do Fator de Necrose Tumoral/biossíntese , Receptor de TWEAK , Fator de Necrose Tumoral alfa/genética , Fatores de Necrose Tumoral/biossíntese
8.
Gait Posture ; 36(3): 449-53, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22609042

RESUMO

The Nintendo Wii Fit™ may provide an affordable alternative to traditional biofeedback or virtual reality systems for retraining or improving motor function in populations with impaired balance. The purpose of this study was to evaluate postural control strategies healthy individuals use to play Wii Fit™ videogames. Sixteen young adults played 10 trials of Ski Slalom and Soccer Heading respectively. Centre of pressure (COP) excursion and three-dimensional movement data were acquired to determine variability in medial-lateral COP sway and shoulder-pelvic movement. While there was no difference in medial-lateral COP variability between games during trial 1, there was a significant difference after 10 trials. COP sway increased (59-75 mm) for Soccer Heading while it decreased (67-33 mm) for Ski Slalom from trial 1 to trial 10. During Ski Slalom participants demonstrated decreased shoulder and pelvic movement combined with increased pelvic-shoulder coupling. Conversely, participants demonstrated greater initial shoulder tilt when playing Soccer Heading, with no reduction in pelvic rotation and tilt. Participants decreased pelvic and trunk movements when skiing, suggesting a greater contribution of lower extremity control while they primarily used a trunk strategy to play Soccer Heading.


Assuntos
Equilíbrio Postural/fisiologia , Amplitude de Movimento Articular/fisiologia , Interface Usuário-Computador , Jogos de Vídeo , Adulto , Biorretroalimentação Psicológica , Estudos de Coortes , Estudos de Avaliação como Assunto , Feminino , Articulação do Quadril/fisiologia , Humanos , Masculino , Postura/fisiologia , Articulação do Ombro/fisiologia , Esqui/fisiologia , Futebol/fisiologia , Adulto Jovem
9.
Toxicol Ind Health ; 25(4-5): 311-20, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19651802

RESUMO

Oxidative stress produced by the dietary or chemical substrates is one of the major causes of liver cell injury. In this study, we compared the effects of two dietary antioxidants, alpha-tocopherol (alpha-T) and beta-carotene (beta-C) against tert-butyl hydroperxide (tBHP)-induced oxidative stress in human hepatoma HepG2 cells. Cell proliferation, lipid peroxidation (LPO), cellular lactate dehydrogenase (LDH), [3H]-aflatoxin B1(AFB1)-DNA adduct formation, and cytochrome P450 2E1 (CYP2E1) expression were determined after antioxidants were added to the tBHP-stressed cells. When compared to an ethanol-based control, all biomarkers for the cell damage were significantly increased by treatments. Treatments of beta-C or the combination of two antioxidants at 50 ppm for 48 h enhanced cell proliferation (P < 0.05) compared to tBHP control. The antioxidative and cytoprotective actions of alpha-T and beta-C, alone or in combination, were associated with modulation of microsomal CYP2E1 expression, corresponding to the regulation of LPO production (P < 0.0001). Our results indicate that alpha-T and beta-C may contribute differently to protection of cellular membrane disruption in CYP2E1-expressing HepG2 cells. Moreover, the combination of alpha-T and beta-C appears to impel the greater protection of pathogenic processes of oxidative stress in liver.


Assuntos
Antioxidantes/farmacologia , Estresse Oxidativo/efeitos dos fármacos , Vitaminas/farmacologia , alfa-Tocoferol/farmacologia , beta Caroteno/farmacologia , terc-Butil Hidroperóxido/farmacologia , Aflatoxina B1/metabolismo , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Citocromo P-450 CYP2E1/biossíntese , Citoproteção , Adutos de DNA/metabolismo , Relação Dose-Resposta a Droga , Sinergismo Farmacológico , Humanos , L-Lactato Desidrogenase/metabolismo , Peroxidação de Lipídeos/efeitos dos fármacos
10.
Oncogene ; 28(9): 1241-7, 2009 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-19151757

RESUMO

The serine/threonine protein kinase, Akt/PKB, has an essential function in cell survival during response to various stresses. Recent studies have demonstrated that Akt isoforms exhibit some distinct physiological functions, but the isotype-specific functions for Akt in the stress response have not been fully identified. In this study, we analysed the cellular response to genotoxic stress using isogenic wild-type, Akt1(-/-) and Akt2(-/-) mouse embryonic fibroblasts (MEFs). Marked hypersensitivity of Akt2(-/-) MEFs was observed to UV irradiation, whereas wild-type and Akt1(-/-) MEFs showed comparable levels of resistance. Akt2(-/-) mouse aortic endothelial cells also showed hypersensitivity to UV and the reconstitution of Akt2 expression in the Akt2(-/-) MEFs restored the UV resistance of the cells. Interestingly, upon UV irradiation, JNK and p38 were significantly upregulated in Akt2(-/-) MEFs, compared to wild-type and Akt1(-/-) MEFs. Additionally, inhibition of JNK and p38 activation reduced UV-induced cell death. Furthermore, both the hyperactivation of JNK and p38 and the UV-induced cell death in Akt2(-/-) MEFs were completely inhibited by restoring Akt2 expression. These results indicate that Akt2, but not Akt1, is essential for cell survival upon UV irradiation, and that Akt2 prevents UV-induced cell death by inhibiting activation of JNK and p38.


Assuntos
Sobrevivência Celular , MAP Quinase Quinase 4/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Raios Ultravioleta , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo , Animais , Apoptose , Western Blotting , Ciclo Celular , Ativação Enzimática , Camundongos
11.
Neurosurg Clin N Am ; 16(4): 657-63, vii, 2005 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-16326289

RESUMO

There is increasing acknowledgment that patients with back pain who are candidates for surgery, will benefit over the long term from less invasive procedures that facilitate dynamic stabilization, rather than fusion. Dynamic stabilization can be addressed by providing assistance using mechanical devices, or relying on biologic processes such as tissue regeneration and repair. The concept of biologic disc repair has grown in recent years because of improved understanding of the cellular and molecular events of disc aging and degeneration. This article describes approaches to cell therapy, reviews relevant studies, and discusses ways to maximize clinical efficacy. Tissue engineering approaches for disc regeneration and healing have significant clinical potential.


Assuntos
Regeneração Tecidual Guiada/métodos , Disco Intervertebral/fisiopatologia , Regeneração/fisiologia , Doenças da Coluna Vertebral/terapia , Humanos , Doenças da Coluna Vertebral/fisiopatologia , Engenharia Tecidual
12.
J Cell Sci ; 113 Pt 21: 3681-2, 2000 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11034894
13.
J Clin Invest ; 106(7): 839-45, 2000 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11018071

RESUMO

Despite prolonged treatment with highly active antiretroviral therapy (HAART), infectious HIV-1 continues to replicate and to reside latently in resting memory CD4(+) T lymphocytes, creating a major obstacle to HIV-1 eradication. It is therefore not surprising to observe a prompt viral rebound after discontinuation of HAART. The nature of the rebounding virus, however, remains undefined. We now report on the genetic characterization of rebounding viruses in eight patients in whom plasma viremia was undetectable throughout about 3 years of HAART. Taking advantage of the extensive length polymorphism in HIV-1 env, we found that in five patients who did not show HIV-1 replication during treatment, the rebound virus was identical to those isolated from the latent reservoir. In three other patients, two of whom had been free of plasma viremia but had showed some residual viral replication, the rebound virus was genetically different from the latent reservoir virus, corresponding instead to minor viral variants detected during the course of treatment in lymphoid tissues. We conclude that in cases with apparent complete HIV-1 suppression by HAART, viral rebound after cessation of therapy could have originated from the activation of virus from the latent reservoir. In patients with incomplete suppression by chemotherapy, however, the viral rebound is likely triggered by ongoing, low-level replication of HIV-1, perhaps occurring in lymphoid tissues.


Assuntos
Terapia Antirretroviral de Alta Atividade , Genes env , Infecções por HIV/tratamento farmacológico , Infecções por HIV/virologia , HIV-1/genética , Polimorfismo de Fragmento de Restrição , Adulto , Contagem de Linfócito CD4 , Humanos , Tecido Linfoide/virologia , Masculino , RNA Viral/isolamento & purificação , Recidiva , Carga Viral , Latência Viral
14.
Biol Pharm Bull ; 23(10): 1220-3, 2000 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11041255

RESUMO

The effects of poly vinyl alcohol (PVA)/Chitosan/Fibroin (PCF)-blended sponge on wound healing in rats were investigated. We excised the skin of a rat, including the dermis, approximately 2 x 2 cm in size. The wound was covered with PCF-blended spongy sheets. The spongy sheets absorbed the exudate, and gained flexibility and softness. Histopathological inspection of the wound 12 d later showed an increase of vascular ingrowth and the absence of inflammatory cells. Regeneration of the skin around the wound was faster than that of the control. We also tested wound healing effects of PVA, Chitosan and Fibroin, alone or in various combinations. Wound healing was accelerated in the order of PCF-blended sponge>Chitosan/Fibroin (CF)-blended sponge>Fibroin (F) sponge > PVA/Chitosan-blended sponge (PC) > Chitosan (C) sponge.


Assuntos
Bandagens , Quitina/análogos & derivados , Fibroínas , Álcool de Polivinil , Cicatrização/efeitos dos fármacos , Animais , Quitosana , Colágeno/biossíntese , Liofilização , Proteínas de Insetos , Masculino , Microscopia Eletrônica de Varredura , Ratos , Ratos Sprague-Dawley , Seda , Pele/patologia , Pele/ultraestrutura
15.
Arch Ophthalmol ; 116(12): 1618-24, 1998 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-9869791

RESUMO

OBJECTIVES: To calculate the volume of bone in 3 areas of the deep lateral orbit that are available for removal in decompression surgery and to demonstrate these 3 areas within a 3-dimensional computed tomographic reconstruction of the orbit. DESIGN: The 3 areas of bone in the deep lateral orbit were designated the lacrimal keyhole, the sphenoid door jamb, and the basin of the inferior orbital fissure. By means of digitized computed tomographic scans, these 3 areas of bone were analyzed by measuring preoperative and postoperative orbital volumes and predicted bony expansion volumes in 9 patients (17 orbits) who underwent deep lateral orbital decompression surgery. We also calculated the volume of bone that could be removed from 11 normal orbits. A 3-dimensional computer reconstruction of an orbital computed tomographic scan was created, and the 3 areas of potential bone were delineated within it. RESULTS: The average volumes of the basin of the inferior orbital fissure, the sphenoid door jamb, the lacrimal keyhole, and the total of the 3 regions were 1.2, 2.9, 1.5, and 5.6 cm3, respectively. The 3 areas of bone contributed variably to the total, with the door jamb contributing the most volume of the 3, nearly twice the value of the other 2. There was, however, a significant amount of interpatient variability, especially for the door jamb region. CONCLUSION: Orbital decompression surgery of the deep lateral wall can provide adequate volume expansion because of the amount and location of potential space that exists in the 3 areas of deep bone.


Assuntos
Aparelho Lacrimal/anatomia & histologia , Órbita/anatomia & histologia , Órbita/cirurgia , Adulto , Idoso , Idoso de 80 Anos ou mais , Descompressão Cirúrgica , Feminino , Doença de Graves/cirurgia , Humanos , Aumento da Imagem , Aparelho Lacrimal/diagnóstico por imagem , Masculino , Pessoa de Meia-Idade , Nervo Óptico/cirurgia , Órbita/diagnóstico por imagem , Osso Esfenoide/anatomia & histologia , Osso Esfenoide/diagnóstico por imagem , Tomografia Computadorizada por Raios X
16.
Brain Res ; 755(1): 170-4, 1997 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-9163556

RESUMO

The effects of microinjection of serotonin-1 (5-HT1) antagonist methiothepin and 5-HT1 agonist buspirone into the nucleus reticularis parvocellularis were investigated in the anaesthetized rats. Methiothepin produced an increase in arterial blood pressure when injected into the left side, but it did a decrease when injected into the right side. On the contrary, buspirone produced a decrease in arterial blood pressure when injected into the left side, but it did an increase when injected into the right side. These findings provide the clue to clarify that there is a reciprocal regulation of arterial blood pressure between the left and right sides in the rat medulla.


Assuntos
Pressão Sanguínea/fisiologia , Bulbo/fisiologia , Metiotepina/farmacologia , Antagonistas da Serotonina/farmacologia , Animais , Buspirona/farmacologia , Relação Dose-Resposta a Droga , Avaliação Pré-Clínica de Medicamentos , Lateralidade Funcional/fisiologia , Masculino , Ratos , Ratos Wistar , Agonistas do Receptor de Serotonina/farmacologia
17.
Proc Natl Acad Sci U S A ; 94(4): 1130-5, 1997 Feb 18.
Artigo em Inglês | MEDLINE | ID: mdl-9037018

RESUMO

The prothoracicotropic hormone (PTTH) of Drosophila melanogaster is a modulator of ecdysteroid (molting hormone) synthesis and was isolated and characterized from extracts of whole larvae (approximately 4 x 10(5) larvae). The purification protocol included delipidation, salt-extraction, heat treatment, conventional column chromatography, and HPLC, and yielded about 50 microg of pure hormone. Biological activity was followed using a ring gland in vitro assay in which ecdysteroidogenesis by control ring glands as measured by radioimmunoassay was compared with ring gland incubations containing active fractions. The molecular weight of the purified PTTH was 45 kDa and N-terminal amino acid sequence analysis indicated that those analyzed sequences displayed no significant homology with known peptides or peptide hormones, including PTTH from the silkmoth, Bombyx mori. Western blot analysis indicated that the native form of Drosophila PTTH was a single 66-kDa polypeptide with N-linked carbohydrate chains and intrachain disulfide bonds. The purified 45-kDa peptide is the deglycosylated form, a result of glycosidase activity present during preparation of the PTTH extract. The deglycosylated form shows heterogeneity, presumably as a result of varying degrees of deglycosylation at the N terminus.


Assuntos
Drosophila melanogaster/química , Glicoproteínas/isolamento & purificação , Hormônios de Inseto/isolamento & purificação , Proteínas do Tecido Nervoso/isolamento & purificação , Animais , Bioensaio , Bombyx , Reações Cruzadas , Endopeptidases/farmacologia , Glicoproteínas/farmacologia , Glicosídeo Hidrolases/farmacologia , Imuno-Histoquímica , Hormônios de Inseto/farmacologia , Larva/química , Proteínas do Tecido Nervoso/farmacologia , Fragmentos de Peptídeos/isolamento & purificação , Fragmentos de Peptídeos/farmacologia , Análise de Sequência , Especificidade da Espécie
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