156 research outputs found

    The suitability of iodinated Angiotensin-(1-7) peptides as pharmacological tools

    Get PDF
    INTRODUCTION: The heptapeptide Angiotensin-(1-7) [(Ang-(1-7)] is a biologically active component of the Renin-Angiotensin System. Pharmacological studies often involve Ang-(1-7) radioactively labelled with (125)I. Given the small size of the original peptide, we investigated whether introduction of a rather bulky iodine label interferes with the biological activity of Ang-(1-7). METHODS: Ang-(1-7) was labelled with nonradioactive iodine with the chloramine-T method. The reaction products were separated on HPLC and analysed with mass spectrometry. The products were tested for biological activity in two ways: The ability of labelled Ang-(1-7) to block Ang II-induced contraction in rat aortic rings was tested in an organ bath setup. The affinity of labelled angiotensin for ACE in rat plasma was examined in vitro. RESULTS: Iodination of Angiotensin-(1-7) resulted in two main products: monoiodinated and diiodinated Ang-(1-7) that could be easily separated on HPLC. In an organ bath experiment, monoiodinated Ang-(1-7) blocked Ang II responses identical to the native compound, whereas diiodinated Ang-(1-7) had lost its ability to block Ang II responses. Likewise, monoiodinated Ang-(1-7) had retained its affinity for ACE, while the affinity of diiodinated Ang-(1-7) was greatly reduced. DISCUSSION: Monoiodinated Ang-(1-7) has a biological activity identical to the native compound, whereas this is lost in diiodinated Ang-(1-7). Therefore, only the monoiodinated radioactive form seems suited for pharmacological studies

    Nitric Oxide-cGMP Signaling in Hypertension:Current and Future Options for Pharmacotherapy

    Get PDF
    For the treatment of systemic hypertension, pharmacological intervention in nitric oxide-cyclic guanosine monophosphate signaling is a well-explored but unexploited option. In this review, we present the identified drug targets, including oxidases, mitochondria, soluble guanylyl cyclase, phosphodiesterase 1 and 5, and protein kinase G, important compounds that modulate them, and the current status of (pre)clinical development. The mode of action of these compounds is discussed, and based upon this, the clinical opportunities. We conclude that drugs that directly target the enzymes of the nitric oxide-cyclic guanosine monophosphate cascade are currently the most promising compounds, but that none of these compounds is under investigation as a treatment option for systemic hypertension

    The Effect of the Thioether-Bridged, Stabilized Angiotensin-(1–7) Analogue Cyclic Ang-(1–7) on Cardiac Remodeling and Endothelial Function in Rats with Myocardial Infarction

    Get PDF
    Modulation of renin-angiotensin system (RAS) by angiotensin-(1–7) (Ang-(1–7)) is an attractive approach to combat the detrimental consequences of myocardial infarction (MI). However Ang-(1–7) has limited clinical potential due to its unfavorable pharmacokinetic profile. We investigated effects of a stabilized, thioether-bridged analogue of Ang-(1–7) called cyclic Ang-(1–7) in rat model of myocardial infarction. Rats underwent coronary ligation or sham surgery. Two weeks thereafter infusion with 0.24 or 2.4 μg/kg/h cAng-(1–7) or saline was started for 8 weeks. Thereafter, cardiac morphometric and hemodynamic variables as wells as aortic endothelial function were measured. The average infarct size was 13.8% and was not changed by cAng-(1–7) treatment. MI increased heart weight and myocyte size, which was restored by cAng-(1–7) to sham levels. In addition, cAng-(1–7) lowered left ventricular end-diastolic pressure and improved endothelial function. The results suggest that cAng-(1–7) is a promising new agent in treatment of myocardial infarction and warrant further research

    Phytoestrogen supplementation and body composition in postmenopausal women: A systematic review and meta-analysis of randomized controlled trials.

    Get PDF
    Phytoestrogen-based medications are commonly used by menopausal women, and especially by obese postmenopausal women, to relieve menopausal symptoms. Substitution of animal with soy protein is often used in weight loss regimens, yet the effect of phytoestrogens, the main constituent of soy foods, on body composition is not completely understood. We conducted a systematic review and meta-analysis to investigate the associations between phytoestrogen supplementation and body weight and the main parameters of body composition in postmenopausal women. A literature search was done using 5 electronic databases from inception to April 2018. Randomized controlled trials (RCTs) with postmenopausal women comparing phytoestrogen supplementation followed by usual diet and placebo were included in the present meta-analysis. From 5932 references, we identified 23 RCTs that met our inclusion criteria, with a total of 1880 postmenopausal women. No association was observed between phytoestrogen supplementation and body weight, body mass index, waist and hip circumference, total fat mass or percentage of body fat. However, the use of phytoestrogens supplementation was associated with a slight decrease in waist-hip ratio; the pooled mean difference was -0.01 cm (95%CI: -0.01 to -0.006). In subgroup analysis, we found a modest decrease in body weight with phytoestrogens supplementation compared with placebo in healthy postmenopausal women [pooled mean difference of changes -0.28 kg (95%CI: -0.52 to -0.04)] and in RCTs with a median number of participants of 66 or less [pooled mean difference of changes -0.49 kg (95%CI: -0.87 to -0.11)]. In contrast, phytoestrogen supplementation was associated with increased body weight in postmenopausal women with preexisting metabolic disorders (prediabetes, type 2 diabetes, prehypertension and hyperlipidemia) [pooled mean difference of changes: 0.78 kg (95%CI: 0.53-1.03)]. In addition, there were some indications that some types of phytoestrogens, such as daidzein, but not soy products or isoflavone mix, could lead to modest adverse changes in body composition in menopausal women. Therefore, future studies should investigate the potential adverse effects of phytoestrogen supplementation on body composition among postmenopausal women

    Phytoestrogen supplementation and body composition in postmenopausal women: A systematic review and meta-analysis of randomized controlled trials

    Get PDF
    Phytoestrogen-based medications are commonly used by menopausal women, and especially by obese postmenopausal women, to relieve menopausal symptoms. Substitution of animal with soy protein is often used in weight loss regimens, yet the effect of phytoestrogens, the main constituent of soy foods, on body composition is not completely understood. We conducted a systematic review and meta-analysis to investigate the associations between phytoestrogen supplementation and body weight and the main parameters of body composition in postmenopausal women. A literature search was done using 5 electronic databases from inception to April 2018. Randomized controlled trials (RCTs) with postmenopausal women comparing phytoestrogen supplementation followed by usual diet and placebo were included in the present meta-analysis. From 5932 references, we identified 23 RCTs that met our inclusion criteria, with a total of 1880 postmenopausal women. No association was observed between phytoestrogen supplementation and body weight, body mass index, waist and hip circumference, total fat mass or percentage of body fat. However, the use of phytoestrogens supplementation was associated with a slight decrease in waist-hip ratio; the pooled mean difference was −0.01 cm (95%CI: −0.01 to −0.006). In subgroup analysis, we found a modest decrease in body weight with phytoestrogens supplementation compared with placebo in healthy postmenopausal women [pooled mean difference of changes −0.28 kg (95%CI: −0.52 to −0.04)] and in RCTs with a median number of participants of 66 or less [pooled mean difference of changes −0.49 kg (95%CI: −0.87 to −0.11)]. In contrast, phytoestrogen supplementation was associated with increased body weight in postmenopausal women with preexisting metabolic disorders (prediabetes, type 2 diabetes, prehypertension and hyperlipidemia) [pooled mean difference of changes: 0.78 kg(95%CI: 0.53–1.03)]. In addition, there were some indications that some types of phytoestrogens, such as daidzein, but not soy products or isoflavone mix, could lead to modest adverse changes in body composition in menopausal women. Therefore, future studies should investigate the potential adverse effects of phytoestrogen supplementation on body composition among postmenopausal women

    COMplex mental health PAThways (COMPAT) Study: A mixed methods study to inform an evidence-based service delivery model for people with complex needs: Study protocol.

    Get PDF
    BACKGROUND: Mental health services for adults, as they are currently configured, have been designed to provide predominantly community-based interventions. It has long been recognised that some patients have such significant clinical and/or risk needs that those needs cannot be adequately met within standard service delivery models, resulting in a pressing need to consider the best models for this group of people. This paper shares a protocol for a mixed methods study that aims to understand: the profile and history of service users described as having complex needs; the decision-making processes by clinicians that lead to complex needs categorisation; service users and carers experience of service use; and, associated economic impact. This protocol describes a comprehensive evaluation that aims to inform an evidence-based service delivery model for people with complex needs. METHODS: We will use a mixed methods design, combining quantitative and qualitative methods using in-depth descriptive and inferential analysis of patient records, written medical notes and in-depth interviews with service users, carers, and clinicians. The study will include five components: (1) a quantitative description and analysis of the demographic clinical characteristics of the patient group; (2) an economic evaluation of alternative patient pathways; (3) semi-structured interviews about service user and carer experiences; (4) using data from components 1-3 to co-produce vignettes jointly with relevant stakeholders involved in the care of service users with complex mental health needs; and, (5) semi-structured interviews about clinical decision-making by clinicians in relation to this patient group, using the vignettes as example case studies. DISCUSSION: The study's key outcomes will be to: examine the resource use and cost-impact associated with alternative care pathways to the NHS and other sectors of the economy (including social care); explore patient health and non-health outcomes associated with alternative care pathways; and, gain an understanding of a complex service user group and how treatment decisions are made to inform consistent and person-centred future service delivery

    Patient profiles of service users with complex mental health needs: an indepth case notes analysis

    Get PDF
    Cheshire and Wirral Partnership NHS Foundation Trust (CWP) provide a wide range of community and inpatient, physical, all-age disability, and mental health care services. The Trust also provide care to a specific cohort of patients who have been defined as having complex mental health needs. This is a broad term used to describe patients who currently receive a package of care commissioned by NHS Cheshire CCG either in an inpatient or community setting, as well as new referrals into the NHS continuing healthcare service who are eligible for NHS funding. This includes patients who are detained under Section 17 of the Mental Health Act or Section 117 aftercare, or who are out of scope, have learning disabilities, are children, those living with dementia who do not have complex, or specialist needs, those with acquired brain injuries and those with physical disabilities. Mental health services for adults, as they are currently configured, have been designed to provide predominantly community-based interventions. It has long been recognised that patients with complex mental health needs cannot be adequately supported within standard service delivery models, resulting in a pressing need to consider the best models for this group of people. There is a paucity of information on the experiences of the service users themselves, particularly of those with complex presentations. The present study aimed to develop a profile of service users with complex mental health needs and provide a detailed exploration of their clinical histories

    Consensus guidelines for lumbar puncture in patients with neurological diseases

    Get PDF
    Introduction Cerebrospinal fluid collection by lumbar puncture (LP) is performed in the diagnostic workup of several neurological brain diseases. Reluctance to perform the procedure is among others due to a lack of standards and guidelines to minimize the risk of complications, such as post-LP headache or back pain. Methods We provide consensus guidelines for the LP procedure to minimize the risk of complications. The recommendations are based on (1) data from a large multicenter LP feasibility study (evidence level II-2), (2) systematic literature review on LP needle characteristics and post-LP complications (evidence level II-2), (3) discussion of best practice within the Joint Programme Neurodegenerative Disease Research Biomarkers for Alzheimer's disease and Parkinson's Disease and Biomarkers for Multiple Sclerosis consortia (evidence level III). Results Our consensus guidelines address contraindications, as well as patient-related and procedure-related risk factors that can influence the development of post-LP complications. Discussion When an LP is performed correctly, the procedure is well tolerated and accepted with a low complication rate
    corecore