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71.
Enhanced purification and production of Müllerian inhibiting substance for therapeutic applications 总被引:1,自引:0,他引:1
Donahoe PK Clarke T Teixeira J Maheswaran S MacLaughlin DT 《Molecular and cellular endocrinology》2003,211(1-2):37-42
It is almost 60 years since Prof. Alfred Jost reported the seminal observations regarding Müllerian inhibiting substance (MIS). His experiments clearly showed that a testicular product other than testosterone, a Müllerian inhibitor, was responsible for Müllerian duct regression. Twenty-five years later Dr. Picon established an organ culture assay which paved the way for the initial studies into the biochemistry and biology of Müllerian inhibiting substance, also known as Anti-Müllerian hormone (AMH), undertaken first in Dr. Nathalie Josso's Laboratory in Paris then in our own laboratory in Boston. Purification of MIS led to cloning the human gene and production of recombinant human (rhMIS). MIS is a 140 kDa glycoprotein homodimer which is activated by a biosynthetic protease, cleaving MIS into an aminoterminus (110 kDa) and a carboxyterminus (25 kDa). The latter domain is sufficient for biological activities. MIS functions by interacting with two receptors; a type II binds the hormone and at type I that initiates downstream signaling. The MIS type II receptor has been cloned and functionally confirmed as distinct from that of other members of the TGFbeta superfamily. MIS can employ a number of type I receptors (ALK2, ALK3, ALK6) and BMP receptor specific SMADS 1, 5, and 8 in various tissue specific contexts. Cell lines derived from human ovarian, breast, and prostate tumors, and from rodent Leydig cell tumors, which respond to MIS in growth inhibition assays, all express the MIS type II receptor. A variety of signal transduction pathways are associated with the grown inhibition mediated by MIS. For example, breast and prostate cancer cell lines use a MIS-mediated NFkappaB pathway leading to G1 arrest and apoptosis. The ovarian cancer cell lines employ a pathway which enhances p16, modulates the E2Fs, and induces apoptosis. These signal transduction events can establish new rational treatment strategies to complement the growth inhibitory effects mediated by MIS. These combination strategies are being tested in vitro, and where appropriate will be tested in vivo using the highly purified MIS preparations, prior to use in early human clinical trials. 相似文献
72.
Filipa Mascarenhas-Melo José Sereno Edite Teixeira-Lemos Sandra Ribeiro Petronila Rocha-Pereira Ethan Cotterill Frederico Teixeira Flávio Reis 《Disease markers》2013,35(2):85-96
Objective. To evaluate the effect of gender and menopause in cardiovascular risk (CVR) in a healthy population based on both classical and nontraditional markers. Methods. 56 men and 68 women (48 pre- and 20 postmenopause) were enrolled in the study. The following markers were analyzed: blood pressure (BP), body mass index (BMI), waist circumference (WC), glucose, total cholesterol (total-c), triglycerides (TGs), low-density lipoprotein cholesterol (LDL-c), oxidized-LDL (Ox-LDL), HDL-c and subpopulations, paraoxonase-1 activity, hsCRP, uric acid, tumor necrosis factor alpha (TNF-α), adiponectin, vascular endothelial growth factor (VEGF), and intercellular adhesion molecular 1 (ICAM1). Results. Relative to the women, men present significantly increased BMI, WC, BP, glucose, total-c, TGs, LDL-c, Ox-LDL, uric acid, and TNF-α and reduced adiponectin and total and large HDL-c. The protective profile of women is lost after menopause with a significantly increased BMI, WC, BP, glucose, LDL-c, Ox-LDL, hsCRP, and VEGF and decreased total and large HDL-c. Significant correlations were found in women population and in postmenopausal women between Ox-LDL and total, large, and small HDL-c and between TNF-α and total, large, and small HDL-c, LDL-c, and Ox-LDL. Conclusions. Men present higher CVR than women who lost protection after menopause, evidenced by nontraditional markers, including Ox-LDL and HDL subpopulations. 相似文献
73.
Edênia C. Menezes Relish Shah Lindsay Laughlin K. Yaragudri Vinod John F. Smiley Catarina Cunha Andrea Balla Henry Sershen Francisco X. Castellanos Andr Corvelo Ctia M. Teixeira 《The Journal of neuroscience》2021,41(12):2723
Early life is a sensitive period, in which enhanced neural plasticity allows the developing brain to adapt to its environment. This plasticity can also be a risk factor in which maladaptive development can lead to long-lasting behavioral deficits. Here, we test how early-life exposure to the selective-serotonin-reuptake-inhibitor (SSRI), fluoxetine, affects motivation, and dopaminergic signaling in adulthood. We show for the first time that mice exposed to fluoxetine in the early postnatal period exhibit a reduction in effort-related motivation. These mice also show blunted responses to amphetamine and reduced dopaminergic activation in a sucrose reward task. Interestingly, we find that the reduction in motivation can be rescued in the adult by administering bupropion, a dopamine-norepinephrine reuptake inhibitor used as an antidepressant and a smoke cessation aid but not by fluoxetine. Taken together, our studies highlight the effects of early postnatal exposure of fluoxetine on motivation and demonstrate the involvement of the dopaminergic system in this process.SIGNIFICANCE STATEMENT The developmental period is characterized by enhanced plasticity. During this period, environmental factors have the potential to lead to enduring behavioral changes. Here, we show that exposure to the SSRI fluoxetine during a restricted period in early life leads to a reduction in adult motivation. We further show that this reduction is associated with decreased dopaminergic responsivity. Finally, we show that motivational deficits induced by early-life fluoxetine exposure can be rescued by adult administration of bupropion but not by fluoxetine. 相似文献
74.
R. James Stubbs Cristiana Duarte Ruairi O'Driscoll Jake Turicchi Dominika Kwasnicka Falko F. Sniehotta Marta M. Marques Graham Horgan Sofus Larsen Antnio Palmeira Inês Santos Pedro J. Teixeira Jason Halford Berit Lilienthal Heitmann 《Obesity facts》2021,14(2):246
There is substantial evidence documenting the effects of behavioural interventions on weight loss (WL). However, behavioural approaches to initial WL are followed by some degree of longer-term weight regain, and large trials focusing on evidence-based approaches to weight loss maintenance (WLM) have generally only demonstrated small beneficial effects. The current state-of-the-art in behavioural interventions for WL and WLM raises questions of (i) how we define the relationship between WL and WLM, (ii) how energy balance (EB) systems respond to WL and influence behaviours that primarily drive weight regain, (iii) how intervention content, mode of delivery and intensity should be targeted to keep weight off, (iv) which mechanisms of action in complex interventions may prevent weight regain and (v) how to design studies and interventions to maximise effective longer-term weight management. In considering these issues a writing team within the NoHoW Consortium was convened to elaborate a position statement, and behaviour change and obesity experts were invited to discuss these positions and to refine them. At present the evidence suggests that developing the skills to self-manage EB behaviours leads to more effective WLM. However, the effects of behaviour change interventions for WL and WLM are still relatively modest and our understanding of the factors that disrupt and undermine self-management of eating and physical activity is limited. These factors include physiological resistance to weight loss, gradual compensatory changes in eating and physical activity and reactive processes related to stress, emotions, rewards and desires that meet psychological needs. Better matching of evidence-based intervention content to quantitatively tracked EB behaviours and the specific needs of individuals may improve outcomes. Improving objective longitudinal tracking of energy intake and energy expenditure over time would provide a quantitative framework in which to understand the dynamics of behaviour change, mechanisms of action of behaviour change interventions and user engagement with intervention components to potentially improve weight management intervention design and evaluation. 相似文献
75.
Puga Luís Teixeira Rogério Paiva Luís Ribeiro Joana Maria Gameiro João Sousa José Pedro Costa Marco Gonçalves Lino 《The international journal of cardiovascular imaging》2021,37(8):2359-2368
The International Journal of Cardiovascular Imaging - There is conflicting evidence regarding the significance of iatrogenic atrial septal defects (iASDs) after transseptal puncture during... 相似文献
76.
Brandão Rondon MU Alves MJ Braga AM Teixeira OT Barretto AC Krieger EM Negrão CE 《Journal of the American College of Cardiology》2002,39(4):676-682
OBJECTIVES: We sought to study: 1) the impact of hemodynamic and left ventricular function on short-term postexercise blood pressure reduction in elderly hypertensive patients; and 2) the 22-h postexercise effects on ambulatory blood pressure in elderly hypertensive patients. BACKGROUND: Although early exercise provokes postexercise blood pressure reduction, the mechanisms underlying this response are not completely understood. Besides, it is unclear whether the reduction in blood pressure after exercise lasts long enough to have clinical relevance in elderly hypertensive patients. METHODS: We studied 24 elderly hypertensive patients (age 68.9 +/- 1.5 years) and 18 age-matched normotensive control subjects (age 68.1 +/- 1.2 years). Cardiac output (carbon dioxide rebreathing) and blood pressure (auscultatory) were measured at rest and after a 45-min period of low-intensity bicycle exercise (50% maximal oxygen uptake) and at 15, 30, 60 and 90 min after exercise. Left ventricular function (by Doppler echocardiography) was also evaluated. Ambulatory blood pressure monitoring was evaluated after 45 min of exercise or 45 min of rest, in a randomized order. RESULTS: In the hypertensive patients, exercise provoked a significant reduction in blood pressure, cardiac output, stroke volume and left ventricular end-diastolic volume. It also provoked a significant reduction in systolic, mean and diastolic blood pressure during a 22-h period, at daytime and nighttime. CONCLUSIONS: The short-term reduction in blood pressure after exercise in elderly hypertensive patients is associated with a decrease in stroke volume and left ventricular end-diastolic volume. The 22-h postexercise reduction in blood pressure demonstrates the clinical relevance of low-intensity exercise in elderly hypertensive patients. 相似文献
77.
Bruna Souza Felix Bravo Laila Klotz De Almeida Balassiano Camila Roos Mariano Da Rocha Carolina Barbosa De Sousa Padilha Carolina Martinezt Torrado Roberta Teixeira Da Silva Jo?o Carlos Regazzi Avelleira 《The Journal of clinical and aesthetic dermatology》2015,8(12):42-47
The growing use of dermal fillers, specifically the use of hyaluronic acid, can be explained by their effectiveness and versatility as well as their favorable safety profiles. Nevertheless, early and late complications with varying levels of severity may occur. The incidence of complications is low and the majority of adverse events are mild (edema, erythema, and local ecchymosis) and of limited duration. However, more severe events, such as ischemia and necrosis, may occur. The symptoms of ischemia can occur immediately after the injection or several hours after the procedure. Here, the authors report three cases of necrosis after hyaluronic acid injection with the first symptoms presenting only several hours after the procedure. The patients were treated immediately after the diagnosis. The aim of this review is to communicate the possibility of the delayed-type presentation of necrosis, present the signs and symptoms that lead to early diagnosis, and review the treatment possibilities of this severe complication.Dermal fillers have been injected with increasing frequency over the past three decades for soft-tissue augmentation by volume expansion in the management of the aging face. In 2012, there were about two million procedures using dermal fillers, according to the American Society of Plastic Surgeons, five percent more than in 2011 and 205 percent more than in 2000, second only to botulinum toxin type A. These minimally invasive and nonsurgical cosmetic procedures were the two most commonly performed in this range of time studied.1,2The growing use of dermal fillers, specifically the use of hyaluronic acid (HA), can be explained by their effectiveness and versatility as well as their favorable safety profiles. Nevertheless, early and late complications with varying levels of severity may occur. The incidence of complications is low and the majority of adverse events are mild (edema, erythema, and local ecchymosis) and of limited duration. However, more severe events, such as ischemia and necrosis, may occur.Injection necrosis is a rare, but important, complication associated with dermal fillers. Necrosis can be attributed to one of two factors—an interruption of vascular supply due to compression or frank obstruction of vessels by direct injection of the material into a vessel itself. The glabella is the injection site commonly believed to be at greater risk for necrosis, but it can also occur at the nasolabial fold.3 Risk factors for intravascular injection include site of application (deep injection of filler products at or near the site of named vessels), volume applied (larger amounts of product can cause a proportionally greater degree of arterial obstruction), and previous scarring (deep tissue scars may stabilize and fix arteries in place, making them easier to penetrate with small sharp needles).4The initial presentation of vascular events may include pain and discomfort disproportionate to what is typically experienced following filler treatments and clinical findings, including blanching, livedo pattern, or violaceous discoloration.4 Although many cases report this immediate post-injection presentation as the typical background seen in a necrosis event, there are few reports with the first symptom presenting only hours after augmentation. See Figures 1 through through3,3, where the authors present three cases of vascular compromise after soft-tissue augmentation with delayed-type presentation.
Open in a separate windowOpen in a separate windowFigures 2Aand 2B.Case 2: Necrosis and secondary infection 48 hours after the HA injection (a). Discrete scars in the affected area after treatment (b).
Open in a separate windowOpen in a separate windowFigures 1Aand 1B.Case 1: Edema, erythema, and progressive violaceous reticulated patch, livedoid area were observed on the left cheek 36 hours after the injection (a). Complete healing five days after hyaluronidase application and nine days after the HA injection (b).
Open in a separate windowOpen in a separate windowFigures 3Aand 3B.Case 3: Necrosis and secondary infection 48 hours after the HA injection (a). Erythema, hipercromia, and discreet scars in the affected area after treatment (b). 相似文献
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