scholarly journals Why Current Doppler Ultrasound Methodology Is Inaccurate in Assessing Cerebral Venous Return: The Alternative of the Ultrasonic Jugular Venous Pulse

2016 ◽  
Vol 2016 ◽  
pp. 1-7 ◽  
Author(s):  
Paolo Zamboni
Keyword(s):  
Doppler Ultrasound ◽  
Average Velocity ◽  
Venous Return ◽  
Automatic Measurement ◽  
Cross Sectional ◽  
Time Average ◽  
Meta Analyses ◽  
Near Future ◽  
Venous Pulse ◽  
The Brain

Assessment of cerebral venous return is growing interest for potential application in clinical practice. Doppler ultrasound (DUS) was used as a screening tool. However, three meta-analyses of qualitative DUS protocol demonstrate a big heterogeneity among studies. In an attempt to improve accuracy, several authors alternatively measured the flow rate, based on the product of the time average velocity with the cross-sectional area (CSA). However, also the quantification protocols lacked of the necessary accuracy. The reasons are as follows: (a) automatic measurement of the CSA assimilates the jugular to a circle, while it is elliptical; (b) the use of just a single CSA value in a pulsatile vessel is inaccurate; (c) time average velocity assessment can be applied only in laminar flow. Finally, the tutorial describes alternative ultrasound calculation of flow based on the Womersley method, which takes into account the variation of the jugular CSA overtime. In the near future, it will be possible to synchronize the electrocardiogram with the brain inflow (carotid distension wave) and with the outflow (jugular venous pulse) in order to nicely have a noninvasive ultrasound picture of the brain-heart axis. US jugular venous pulse may have potential use in neurovascular, neurocognitive, neurosensorial, and neurodegenerative disorders.

scholarly journals The Oscillating Component of the Internal Jugular Vein Flow: The Overlooked Element of Cerebral Circulation

2015 ◽  
Vol 2015 ◽  
pp. 1-9 ◽  
Author(s):  
Francesco Sisini ◽  
Eleuterio Toro ◽  
Mauro Gambaccini ◽  
Paolo Zamboni
Keyword(s):  
Pressure Gradient ◽  
Jugular Vein ◽  
Venous Pressure ◽  
Blood Velocity ◽  
Cross Sectional ◽  
Instantaneous Pressure ◽  
Cardiac Period ◽  
Venous Pulse ◽  
The Brain ◽  
Cardiac Haemodynamics

The jugular venous pulse (JVP) provides valuable information about cardiac haemodynamics and filling pressures and is an indirect estimate of the central venous pressure (CVP). Recently it has been proven that JVP can be obtained by measuring the cross-sectional area (CSA) of the IJV on each sonogram of an ultrasound B-mode sonogram sequence. It has also been proven that during its pulsation the IJV is distended and hence that the pressure gradient drives the IJV haemodynamics. If this is true, then it will imply the following: (i) the blood velocity in the IJV is a periodic function of the time with period equal to the cardiac period and (ii) the instantaneous blood velocity is given by a time function that can be derived from a flow-dynamics theory that uses the instantaneous pressure gradient as a parameter. The aim of the present study is to confirm the hypothesis that JVP regulates the IJV blood flow and that pressure waves are transmitted from the heart toward the brain through the IJV wall.

scholarly journals To which extent are per-and poly-fluorinated substances associated to metabolic syndrome?

2021 ◽  
Vol 0 (0) ◽  
Author(s):  
Maryam Zare Jeddi ◽  
Rozita Soltanmohammadi ◽  
Giulia Barbieri ◽  
Aline S. C. Fabricio ◽  
Gisella Pitter ◽  
...  
Keyword(s):  
Metabolic Syndrome ◽  
General Population ◽  
Meta Analysis ◽  
Small Body ◽  
Epidemiological Studies ◽  
Cross Sectional ◽  
Random Effects Models ◽  
Epidemiologic Evidence ◽  
Adults And Children ◽  
Meta Analyses

Abstract Exposure to per- and polyfluoroalkyl substances (PFAS), ubiquitous persistent environmental contaminants, has led to substantial global concern due to their potential environmental and human health effects. Several epidemiological studies have assessed the possible association between PFAS exposure and risk of metabolic syndrome (MetS), however, the results are ambiguous. The aim of this study was to assess the current human epidemiologic evidence on the association between exposure to PFAS and MetS. We performed a systematic search strategy using three electronic databases (PubMed, Scopus, and Web of Science) for relevant studies concerning the associations of PFAS with MetS and its clinical relevance from inception until January 2021. We undertook meta-analyses where there were five or more studies with exposure and outcomes assessments that were reasonably comparable. The pooled odd ratios (ORs) were calculated using random effects models and heterogeneity among studies was assessed by I2 index and Q test. A total of 12 cross-sectional studies (10 studies on the general population and two studies in the occupational settings) investigated the association between PFAS exposure and MetS. We pooled data from seven studies on the general population for perfluorooctanoic acid (PFOA) and perfluorooctanesulfonate (PFOS) and five studies for perfluorohexanesulfonate (PFHxS) and perfluorononanoic acid (PFNA). Predominately, most studies reported no statistically significant association between concentrations of PFAS and MetS. In the meta-analysis, the overall measure of effect was not statistically significant, showing no evidence of an association between concentrations of PFOA, PFOS, PFNA, and PFHxS and the risk of MetS. Based on the results of the meta-analysis, current small body of evidence does not support association between PFAS and MetS. However, due to limited number of studies and substantial heterogeneity, results should be interpreted with caution. Further scrutinizing cohort studies are needed to evaluate the association between various and less well-known PFAS substances and their mixture with MetS and its components in both adults and children in different settings.

scholarly journals Related Factors and Clinical Outcomes of Osteosarcopenia: A Narrative Review

Nutrients ◽  
2021 ◽  
Vol 13 (2) ◽  
pp. 291
Author(s):  
Tatsuro Inoue ◽  
Keisuke Maeda ◽  
Ayano Nagano ◽  
Akio Shimizu ◽  
Junko Ueshima ◽  
...  
Keyword(s):  
Older Adults ◽  
Longitudinal Studies ◽  
Clinical Outcomes ◽  
Daily Living ◽  
Community Dwelling ◽  
Related Factors ◽  
Cross Sectional ◽  
Meta Analyses ◽  
Community Dwelling Older Adults

Osteopenia/osteoporosis and sarcopenia are common geriatric diseases among older adults and harm activities of daily living (ADL) and quality of life (QOL). Osteosarcopenia is a unique syndrome that is a concomitant of both osteopenia/osteoporosis and sarcopenia. This review aimed to summarize the related factors and clinical outcomes of osteosarcopenia to facilitate understanding, evaluation, prevention, treatment, and further research on osteosarcopenia. We searched the literature to include meta-analyses, reviews, and clinical trials. The prevalence of osteosarcopenia among community-dwelling older adults is significantly higher in female (up to 64.3%) compared to male (8–11%). Osteosarcopenia is a risk factor for death, fractures, and falls based on longitudinal studies. However, the associations between osteosarcopenia and many other factors have been derived based on cross-sectional studies, so the causal relationship is not clear. Few studies of osteosarcopenia in hospitals have been conducted. Osteosarcopenia is a new concept and has not yet been fully researched its relationship to clinical outcomes. Longitudinal studies and high-quality interventional studies are warranted in the future.

Prevalence of Cognitive Impairment and Dementia in Older Adults Living at High Altitude: A Systematic Review and Meta-Analysis

2021 ◽  
pp. 1-11
Author(s):  
Diego Urrunaga-Pastor ◽  
Diego Chambergo-Michilot ◽  
Fernando M. Runzer-Colmenares ◽  
Josmel Pacheco-Mendoza ◽  
Vicente A. Benites-Zapata
Keyword(s):  
Older Adults ◽  
Cognitive Impairment ◽  
High Altitude ◽  
Web Of Science ◽  
Meta Analysis ◽  
Cross Sectional ◽  
Language Restriction ◽  
Newcastle Ottawa Scale ◽  
Meta Analyses ◽  
Ottawa Scale

<b><i>Introduction:</i></b> Dementia is a chronic disease with a variable prevalence throughout the world; however, this could be higher at high-altitude populations. We aimed to summarize the prevalence of cognitive impairment and dementia in older adults living at high altitude. <b><i>Methods:</i></b> We searched in PubMed, Medline, Scopus, Web of Science, and Embase and included the studies published from inception to July 20, 2020, with no language restriction, which reported the frequency of cognitive impairment or dementia in older adults living at high-altitude populations. Random-effects meta-analyses were performed to calculate the overall prevalence and 95% confidence intervals (95% CI) of cognitive impairment and dementia. The risk of bias was evaluated using the Newcastle-Ottawa Scale (NOS) adapted for cross-sectional studies. <b><i>Results:</i></b> Six studies were included (3,724 participants), and 5 of the 6 included studies were carried out in Latin America. The altitude ranged from 1,783 to 3,847 m, the proportion of women included varied from 38.7 to 65.6%, and the proportion of participants with elementary or illiterate educational level ranged from 71.7 to 97.6%. The overall prevalence of cognitive impairment was 22.0% (95% CI: 8–40, <i>I</i><sup>2</sup>: 99%), and the overall prevalence of dementia was 11.0% (95% CI: 6–17, <i>I</i><sup>2</sup>: 92%). In a subgroup analysis according to the instrument used to evaluate cognitive impairment, the prevalence of cognitive impairment was 21.0% (95% CI: 5–42, <i>I</i><sup>2</sup>: 99%) in the MMSE group while the prevalence was 29.0% (95% CI: 0–78) in the non-MMSE group. <b><i>Conclusions:</i></b> The prevalence of cognitive impairment and dementia in older adults living at high altitude is almost twice the number reported in some world regions.

scholarly journals Research on the Computed Tomography Pebble Flow Detecting System for HTR-PM

2017 ◽  
Vol 2017 ◽  
pp. 1-13
Author(s):  
Xin Wan ◽  
Ximing Liu ◽  
Jichen Miao ◽  
Peng Cong ◽  
Yuai Zhang ◽  
...  
Keyword(s):  
Computed Tomography ◽  
Three Dimensional ◽  
Helical Ct ◽  
Design Parameters ◽  
Three Dimensional Model ◽  
Safe Operation ◽  
Cross Sectional ◽  
Ct System ◽  
Near Future ◽  
Pebble Flow

Pebble dynamics is important for the safe operation of pebble-bed high temperature gas-cooled reactors and is a complicated problem of great concern. To investigate it more authentically, a computed tomography pebble flow detecting (CT-PFD) system has been constructed, in which a three-dimensional model is simulated according to the ratio of 1 : 5 with the core of HTR-PM. A multislice helical CT is utilized to acquire the reconstructed cross-sectional images of simulated pebbles, among which special tracer pebbles are designed to indicate pebble flow. Tracer pebbles can be recognized from many other background pebbles because of their heavy kernels that can be resolved in CT images. The detecting principle and design parameters of the system were demonstrated by a verification experiment on an existing CT system in this paper. Algorithms to automatically locate the three-dimensional coordinates of tracer pebbles and to rebuild the trajectory of each tracer pebble were presented and verified. The proposed pebble-detecting and tracking technique described in this paper will be implemented in the near future.

scholarly journals Maternal Hypertensive Pregnancy Disorders and Mental and Behavioral Disorders in the Offspring: a Review

2021 ◽  
Vol 23 (5) ◽  
Author(s):  
Rachel Robinson ◽  
Anna Lähdepuro ◽  
Soile Tuovinen ◽  
Polina Girchenko ◽  
Ville Rantalainen ◽  
...  
Keyword(s):  
Behavioral Disorders ◽  
Sound Studies ◽  
Original Research ◽  
Case Control Studies ◽  
Cross Sectional ◽  
Hypertensive Pregnancy ◽  
Increased Risk ◽  
Meta Analyses ◽  
Mental And Behavioral Disorders ◽  
Pregnancy Disorders

Abstract Purpose of Review We review here recent original research and meta-analytic evidence on the associations of maternal hypertensive pregnancy disorders and mental and behavioral disorders in the offspring. Recent Findings Seven meta-analyses and 11 of 16 original research studies published since 2015 showed significant associations between maternal hypertensive pregnancy disorders and offspring mental and behavioral disorders. Evidence was most consistent in meta-analyses and high-quality cohort studies. The associations, independent of familial confounding, were observed on different mental and behavioral disorders in childhood and schizophrenia in adulthood. Preterm birth and small-for-gestational age birth emerged as possible moderators and mediators of the associations. Cross-sectional and case-control studies yielded inconsistent findings, but had lower methodological quality. Summary Accumulating evidence from methodologically sound studies shows that maternal hypertensive pregnancy disorders are associated with an increased risk of mental and behavioral disorders in the offspring in childhood. More studies on adult mental disorders are needed.

scholarly journals The Impact of Vegan Diet in the Prevention and Treatment of Type 2 Diabetes: A Systematic Review

Nutrients ◽  
2021 ◽  
Vol 13 (6) ◽  
pp. 2123
Author(s):  
Daniela Pollakova ◽  
Aikaterini Andreadi ◽  
Francesca Pacifici ◽  
David Della-Morte ◽  
Davide Lauro ◽  
...  
Keyword(s):  
Type 2 Diabetes ◽  
Assessment Tool ◽  
Vegan Diet ◽  
Cochrane Library ◽  
Diabetic Patients ◽  
Cross Sectional ◽  
Observational Cohort ◽  
Meta Analyses ◽  
The Impact

A protective effect of vegan diets on health outcomes has been observed in previous studies, but its impact on diabetes is still debated. The aim of this review is to assess the relationship between vegan diets and the risk for type 2 diabetes (T2D) along with its effect on glycemic control and diabetes-related complications. In accordance with PRISMA (Preferred Reporting Items for Systematic Reviews and Meta–Analyses) guidelines, Pubmed and Cochrane library databases were systematically searched for all relevant studies. Seven observational and eight randomized controlled (RCTs) studies were included. The methodological quality of studies was assessed using the National Institutes of Health quality assessment tool for observational cohort and cross-sectional studies and the Cochrane Risk of Bias Tool for RCTs. We found that a vegan diet is associated with lower T2D prevalence or incidence and in T2D patients decreases high glucose values and improves glucose homeostasis, as reported from the majority of included studies. This approach seems to be comparable to other recommended healthful eating models, but as it may have potential adverse effects associated with the long-term exclusion of some nutrients, appropriate nutritional planning and surveillance are recommended, particularly in specific groups of diabetic patients such as frail elderly, adolescents, and pregnant or breastfeeding women.

scholarly journals Arm Based on LEg blood pressures (ABLE-BP): can systolic leg blood pressure measurements predict systolic brachial blood pressure? Protocol for an individual participant data meta-analysis from the INTERPRESS-IPD Collaboration

BMJ Open ◽  
2021 ◽  
Vol 11 (3) ◽  
pp. e040481
Author(s):  
Sinead T J McDonagh ◽  
James P Sheppard ◽  
Fiona C Warren ◽  
Kate Boddy ◽  
Leon Farmer ◽  
...  
Keyword(s):  
Blood Pressure ◽  
Public Involvement ◽  
Meta Analysis ◽  
Patient And Public Involvement ◽  
Prognostic Models ◽  
Individual Participant Data ◽  
Dissemination Strategy ◽  
Cross Sectional ◽  
Individual Participant ◽  
Meta Analyses

IntroductionBlood pressure (BP) is normally measured on the upper arm, and guidelines for the diagnosis and treatment of high BP are based on such measurements. Leg BP measurement can be an alternative when brachial BP measurement is impractical, due to injury or disability. Limited data exist to guide interpretation of leg BP values for hypertension management; study-level systematic review findings suggest that systolic BP (SBP) is 17 mm Hg higher in the leg than the arm. However, uncertainty remains about the applicability of this figure in clinical practice due to substantial heterogeneity.AimsTo examine the relationship between arm and leg SBP, develop and validate a multivariable model predicting arm SBP from leg SBP and investigate the prognostic association between leg SBP and cardiovascular disease and mortality.Methods and analysisIndividual participant data (IPD) meta-analyses using arm and leg SBP measurements for 33 710 individuals from 14 studies within the Inter-arm blood pressure difference IPD (INTERPRESS-IPD) Collaboration. We will explore cross-sectional relationships between arm and leg SBP using hierarchical linear regression with participants nested by study, in multivariable models. Prognostic models will be derived for all-cause and cardiovascular mortality and cardiovascular events.Ethics and disseminationData originate from studies with prior ethical approval and consent, and data sharing agreements are in place—no further approvals are required to undertake the secondary analyses proposed in this protocol. Findings will be published in peer-reviewed journal articles and presented at conferences. A comprehensive dissemination strategy is in place, integrated with patient and public involvement.PROSPERO registration numberCRD42015031227.

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