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Fluoride exposure and cognitive neurodevelopment: Systematic review and dose-response meta-analysis.Environmental Research Mar 2023Many uncertainties still surround the possible harmful effect of fluoride exposure on cognitive neurodevelopment in children. The aim of this systematic review and... (Meta-Analysis)
Meta-Analysis Review
Many uncertainties still surround the possible harmful effect of fluoride exposure on cognitive neurodevelopment in children. The aim of this systematic review and meta-analysis was to characterize this relation through a dose-response approach, by comparing the intelligence quotient (IQ) scores in the highest versus the lowest fluoride exposure category with a random-effects model, within a one-stage dose-response meta-analysis based on a cubic spline random-effects model. Out of 1996 potentially relevant literature records, 33 studies were eligible for this review, 30 of which were also suitable for meta-analysis. The summary mean difference of IQ score, comparing highest versus lowest fluoride categories and considering all types of exposure, was -4.68 (95% confidence interval-CI -6.45; -2.92), with a value of -5.60 (95% CI -7.76; -3.44) for drinking water fluoride and -3.84 (95% CI -7.93; 0.24) for urinary fluoride. Dose-response analysis showed a substantially linear IQ decrease for increasing water fluoride above 1 mg/L, with -3.05 (95% CI -4.06; -2.04) IQ points per 1 mg/L up to 2 mg/L, becoming steeper above such level. A weaker and substantially linear decrease of -2.15 (95% CI -4.48; 0.18) IQ points with increasing urinary fluoride emerged above 0.28 mg/L (approximately reflecting a water fluoride content of 0.7 mg/L). The inverse association between fluoride exposure and IQ was particularly strong in the studies at high risk of bias, while no adverse effect emerged in the only study judged at low risk of bias. Overall, most studies suggested an adverse effect of fluoride exposure on children's IQ, starting at low levels of exposure. However, a major role of residual confounding could not be ruled out, thus indicating the need of additional prospective studies at low risk of bias to conclusively assess the relation between fluoride exposure and cognitive neurodevelopment.
Topics: Child; Humans; Fluorides; Intelligence; Prospective Studies; Drinking Water; Cognition
PubMed: 36639015
DOI: 10.1016/j.envres.2023.115239 -
Scandinavian Journal of Medicine &... Apr 2019Isometric training is used in the rehabilitation and physical preparation of athletes, special populations, and the general public. However, little consensus exists...
Isometric training is used in the rehabilitation and physical preparation of athletes, special populations, and the general public. However, little consensus exists regarding training guidelines for a variety of desired outcomes. Understanding the adaptive response to specific loading parameters would be of benefit to practitioners. The objective of this systematic review, therefore, was to detail the medium- to long-term adaptations of different types of isometric training on morphological, neurological, and performance variables. Exploration of the relevant subject matter was performed through MEDLINE, PubMed, SPORTDiscus, and CINAHL databases. English, full-text, peer-reviewed journal articles and unpublished doctoral dissertations investigating medium- to long-term (≥3 weeks) adaptations to isometric training in humans were identified. These studies were evaluated further for methodological quality. Twenty-six research outputs were reviewed. Isometric training at longer muscle lengths (0.86%-1.69%/week, ES = 0.03-0.09/week) produced greater muscular hypertrophy when compared to equal volumes of shorter muscle length training (0.08%-0.83%/week, ES = -0.003 to 0.07/week). Ballistic intent resulted in greater neuromuscular activation (1.04%-10.5%/week, ES = 0.02-0.31/week vs 1.64%-5.53%/week, ES = 0.03-0.20/week) and rapid force production (1.2%-13.4%/week, ES = 0.05-0.61/week vs 1.01%-8.13%/week, ES = 0.06-0.22/week). Substantial improvements in muscular hypertrophy and maximal force production were reported regardless of training intensity. High-intensity (≥70%) contractions are required for improving tendon structure and function. Additionally, long muscle length training results in greater transference to dynamic performance. Despite relatively few studies meeting the inclusion criteria, this review provides practitioners with insight into which isometric training variables (eg, joint angle, intensity, intent) to manipulate to achieve desired morphological and neuromuscular adaptations.
Topics: Adaptation, Physiological; Humans; Isometric Contraction; Muscle, Skeletal; Resistance Training; Tendons
PubMed: 30580468
DOI: 10.1111/sms.13375 -
Sports Medicine (Auckland, N.Z.) Apr 2015Maximizing the hypertrophic response to resistance training (RT) is thought to be best achieved by proper manipulation of exercise program variables including exercise... (Meta-Analysis)
Meta-Analysis Review
BACKGROUND
Maximizing the hypertrophic response to resistance training (RT) is thought to be best achieved by proper manipulation of exercise program variables including exercise selection, exercise order, length of rest intervals, intensity of maximal load, and training volume. An often overlooked variable that also may impact muscle growth is repetition duration. Duration amounts to the sum total of the concentric, eccentric, and isometric components of a repetition, and is predicated on the tempo at which the repetition is performed.
OBJECTIVE
We conducted a systematic review and meta-analysis to determine whether alterations in repetition duration can amplify the hypertrophic response to RT.
METHODS
Studies were deemed eligible for inclusion if they met the following criteria: (1) were an experimental trial published in an English-language refereed journal; (2) directly compared different training tempos in dynamic exercise using both concentric and eccentric repetitions; (3) measured morphologic changes via biopsy, imaging, and/or densitometry; (4) had a minimum duration of 6 weeks; (5) carried out training to muscle failure, defined as the inability to complete another concentric repetition while maintaining proper form; and (6) used human subjects who did not have a chronic disease or injury. A total of eight studies were identified that investigated repetition duration in accordance with the criteria outlined.
RESULTS
Results indicate that hypertrophic outcomes are similar when training with repetition durations ranging from 0.5 to 8 s.
CONCLUSIONS
From a practical standpoint it would seem that a fairly wide range of repetition durations can be employed if the primary goal is to maximize muscle growth. Findings suggest that training at volitionally very slow durations (>10s per repetition) is inferior from a hypertrophy standpoint, although a lack of controlled studies on the topic makes it difficult to draw definitive conclusions.
Topics: Adaptation, Physiological; Humans; Muscle Fatigue; Muscle Strength; Muscle, Skeletal; Resistance Training; Time Factors
PubMed: 25601394
DOI: 10.1007/s40279-015-0304-0 -
International Journal of Environmental... Oct 2021The load in resistance training is considered to be a critical variable for neuromuscular adaptations. Therefore, it is important to assess the effects of applying... (Review)
Review
Effects of Resistance Training Performed with Different Loads in Untrained and Trained Male Adult Individuals on Maximal Strength and Muscle Hypertrophy: A Systematic Review.
The load in resistance training is considered to be a critical variable for neuromuscular adaptations. Therefore, it is important to assess the effects of applying different loads on the development of maximal strength and muscular hypertrophy. The aim of this study was to systematically review the literature and compare the effects of resistance training that was performed with low loads versus moderate and high loads in untrained and trained healthy adult males on the development of maximal strength and muscle hypertrophy during randomized experimental designs. The Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines (2021) were followed with the eligibility criteria defined according to participants, interventions, comparators, outcomes, and study design (PICOS): (P) healthy males between 18 and 40 years old, (I) interventions performed with low loads, (C) interventions performed with moderate or high loads, (O) development of maximal strength and muscle hypertrophy, and (S) randomized experimental studies with between- or within-subject parallel designs. The literature search strategy was performed in three electronic databases (Embase, PubMed, and Web of Science) on 22 August 2021. Twenty-three studies with a total of 563 participants (80.6% untrained and 19.4% trained) were selected. The studies included both relative and absolute loads. All studies were classified as being moderate-to-high methodological quality, although only two studies had a score higher than six points. The main findings indicated that the load magnitude that was used during resistance training influenced the dynamic strength and isometric strength gains. In general, comparisons between the groups (i.e., low, moderate, and high loads) showed higher gains in 1RM and maximal voluntary isometric contraction when moderate and high loads were used. In contrast, regarding muscle hypertrophy, most studies showed that when resistance training was performed to muscle failure, the load used had less influence on muscle hypertrophy. The current literature shows that gains in maximal strength are more pronounced with high and moderate loads compared to low loads in healthy adult male populations. However, for muscle hypertrophy, studies indicate that a wide spectrum of loads (i.e., 30 to 90% 1RM) may be used for healthy adult male populations.
Topics: Adolescent; Adult; Humans; Hypertrophy; Male; Men; Muscle Strength; Muscle, Skeletal; Resistance Training; Young Adult
PubMed: 34769755
DOI: 10.3390/ijerph182111237 -
Sports Medicine - Open Dec 2015The present article systematically reviews recent literature on the in vivo adaptation of asymptomatic human tendons following increased chronic mechanical loading, and... (Review)
Review
BACKGROUND
The present article systematically reviews recent literature on the in vivo adaptation of asymptomatic human tendons following increased chronic mechanical loading, and meta-analyzes the loading conditions, intervention outcomes, as well as methodological aspects.
METHODS
The search was performed in the databases PubMed, Web of Knowledge, and Scopus as well as in the reference lists of the eligible articles. A study was included if it conducted (a) a longitudinal exercise intervention (≥8 weeks) on (b) healthy humans (18 to 50 years), (c) investigating the effects on mechanical (i.e., stiffness), material (i.e., Young's modulus) and/or morphological properties (i.e., cross-sectional area (CSA)) of tendons in vivo, and was reported (d) in English language. Weighted average effect sizes (SMD, random-effects) and heterogeneity (Q and I statistics) of the intervention-induced changes of tendon stiffness, Young's modulus, and CSA were calculated. A subgroup analysis was conducted regarding the applied loading intensity, muscle contraction type, and intervention duration. Further, the methodological study quality and the risk of bias were assessed.
RESULTS
The review process yielded 27 studies with 37 separate interventions on either the Achilles or patellar tendon (264 participants). SMD was 0.70 (confidence interval: 0.51, 0.88) for tendon stiffness (N=37), 0.69 (0.36, 1.03) for Young's modulus (N=17), and 0.24 (0.07, 0.42) for CSA (N=33), with significant overall intervention effects (p<0.05). The heterogeneity analysis (stiffness: I =30%; Young's modulus: I =57%; CSA: I =21%) indicated that differences in the loading conditions may affect the adaptive responses. The subgroup analysis confirmed that stiffness adaptation significantly (p<0.05) depends on loading intensity (I =0%), but not on muscle contraction type. Although not significantly different, SMD was higher for interventions with longer duration (≥12 weeks). The average score of 71±9% in methodological quality assessment indicated an appropriate quality of most studies.
CONCLUSIONS
The present meta-analysis provides elaborate statistical evidence that tendons are highly responsive to diverse loading regimens. However, the data strongly suggests that loading magnitude in particular plays a key role for tendon adaptation in contrast to muscle contraction type. Furthermore, intervention-induced changes in tendon stiffness seem to be more attributed to adaptations of the material rather than morphological properties.
PubMed: 27747846
DOI: 10.1186/s40798-015-0009-9 -
Apoptosis : An International Journal on... Aug 2022Programmed cell death is considered a key player in a variety of cellular processes that helps to regulate tissue growth, embryogenesis, cell turnover, immune response,... (Review)
Review
Programmed cell death is considered a key player in a variety of cellular processes that helps to regulate tissue growth, embryogenesis, cell turnover, immune response, and other biological processes. Among different types of cell death, apoptosis has been studied widely, especially in the field of cancer research to understand and analyse cellular mechanisms, and signaling pathways that control cell cycle arrest. Hallmarks of different types of cell death have been identified by following the patterns and events through microscopy. Identified biomarkers have also supported drug development to induce cell death in cancerous cells. There are various serological and microscopic techniques with advantages and limitations, that are available and are being utilized to detect and study the mechanism of cell death. The complexity of the mechanism and difficulties in distinguishing among different types of programmed cell death make it challenging to carry out the interventions and delay its progression. In this review, mechanisms of different forms of programmed cell death along with their conventional and unconventional methods of detection of have been critically reviewed systematically and categorized on the basis of morphological hallmarks and biomarkers to understand the principle, mechanism, application, advantages and disadvantages of each method. Furthermore, a very comprehensive comparative analysis has been drawn to highlight the most efficient and effective methods of detection of programmed cell death, helping researchers to make a reliable and prudent selection among the available methods of cell death assay. Conclusively, how programmed cell death detection methods can be improved and can provide information about distinctive stages of cell death detection have been discussed.
Topics: Apoptosis; Biomarkers; Cell Death; Signal Transduction
PubMed: 35713779
DOI: 10.1007/s10495-022-01735-y -
Archives of Gynecology and Obstetrics Jan 2023Endometriosis is a common chronic gynecological disease defined as the presence of endometrial glands and stroma tissue outside the uterus. Gestrinone is an effective... (Meta-Analysis)
Meta-Analysis Review
PURPOSE
Endometriosis is a common chronic gynecological disease defined as the presence of endometrial glands and stroma tissue outside the uterus. Gestrinone is an effective antiestrogen that induces endometrial atrophy and/or amenorrhea. The purpose of this systematic review is to provide an evaluation of safety and effectiveness of gestrinone for the treatment of endometriosis.
METHODS
We performed a search in six electronic databases: PubMed, MEDLINE (ovid), Embase, Cochrane CENTRAL (clinical trials), Web of Science and Scopus. Our selected primary outcomes were the changes in dysmenorrhea, pain relief including pelvic pain and dyspareunia. The secondary outcomes embrace hormones parameters, pregnancy rate and adverse events.
RESULTS
Of 3269 references screened, 16 studies were included involving 1286 women. All studies compared gestrinone with other drugs treatments (placebo, Danazol, Mifepristone tablets, Leuprolide acetate, Quyu Jiedu Recipe) during 6 months. When compared with other drugs treatments, gestrinone relieved dysmenorrhea, pelvic pain, and morphologic response in the ovary. There was an increase on the pregnancy rate. Regarding the side effects observed, gestrinone showed the same adverse events and increased the risk of acne and seborrhea when compared to other treatments. Even if there was any difference in efficacy between gestrinone, danazol, leuprolide acetate, or Quyu Jiedu Recipe Chinese Medicine, it remains unclear due to insufficient data.
CONCLUSION
Based limited evidence available suggests that gestrinone appeared to be safe and may have some efficacy advantages over danazol, as well as other therapeutic interventions for treating endometriosis. However, this conclusion should be interpreted with caution, due the quality of the evidence provided is generally very low or unclear.
TRIAL REGISTRATION
CRD42021284148.
Topics: Pregnancy; Female; Humans; Endometriosis; Gestrinone; Danazol; Leuprolide; Dysmenorrhea; Pelvic Pain
PubMed: 36434439
DOI: 10.1007/s00404-022-06846-0 -
Journal of Strength and Conditioning... Sep 2017Schoenfeld, BJ, Ogborn, DI, Vigotsky, AD, Franchi, MV, and Krieger, JW. Hypertrophic effects of concentric vs. eccentric muscle actions: A systematic review and... (Meta-Analysis)
Meta-Analysis Review
Schoenfeld, BJ, Ogborn, DI, Vigotsky, AD, Franchi, MV, and Krieger, JW. Hypertrophic effects of concentric vs. eccentric muscle actions: A systematic review and meta-analysis. J Strength Cond Res 31(9): 2599-2608, 2017-Controversy exists as to whether different dynamic muscle actions produce divergent hypertrophic responses. The purpose of this paper was to conduct a systematic review and meta-analysis of randomized controlled trials comparing the hypertrophic effects of concentric vs. eccentric training in healthy adults after regimented resistance training (RT). Studies were deemed eligible for inclusion if they met the following criteria: (a) were an experimental trial published in an English-language refereed journal; (b) directly compared concentric and eccentric actions without the use of external implements (i.e., blood pressure cuffs) and all other RT variables equivalent; (c) measured morphologic changes using biopsy, imaging (magnetic resonance imaging, computerized tomography, or ultrasound), bioelectrical impedance, and/or densitometry; (d) had a minimum duration of 6 weeks; and (e) used human participants without musculoskeletal injury or any health condition that could directly, or through the medications associated with the management of said condition, be expected to impact the hypertrophic response to resistance exercise. A systematic literature search determined that 15 studies met inclusion criteria. Results showed that eccentric muscle actions resulted in a greater effect size (ES) compared with concentric actions, but results did not reach statistical significance (ES difference = 0.25 ± 0.13; 95% confidence interval: -0.03 to 0.52; p = 0.076). The mean percent change in muscle growth across studies favored eccentric compared with concentric actions (10.0% vs. 6.8, respectively). The findings indicate the importance of including eccentric and concentric actions in a hypertrophy-oriented RT program, as both have shown to be effective in increasing muscle hypertrophy.
Topics: Adult; Biopsy; Electric Impedance; Exercise; Female; Humans; Magnetic Resonance Imaging; Male; Muscle, Skeletal; Randomized Controlled Trials as Topic; Resistance Training
PubMed: 28486337
DOI: 10.1519/JSC.0000000000001983 -
Current Environmental Health Reports Dec 2023We performed a systematic review and meta-analysis on the relation between fluoride exposure and skeletal fluorosis (SF) using a novel statistical methodology for... (Meta-Analysis)
Meta-Analysis Review
PURPOSE OF REVIEW
We performed a systematic review and meta-analysis on the relation between fluoride exposure and skeletal fluorosis (SF) using a novel statistical methodology for dose-response modeling.
RECENT FINDINGS
Skeletal fluorosis, a major health issue that is endemic in some regions, affects millions of people worldwide. However, data regarding the dose-response relation between fluoride exposure and SF are limited and outdated. We included twenty-three studies in the meta-analysis. When comparing the highest versus the lowest fluoride category, the summary risk ratio (RR) for SF prevalence was 2.05 (95% CI 1.60; 2.64), with a value of 2.73 (95% CI 1.92; 3.90) for drinking water and 1.40 (95% CI 0.90; 2.17) for urinary fluoride. The RR by the risk of bias (RoB) was 2.37 (95% CI 1.56; 3.58) and 1.78 (95% CI 1.34; 2.36) for moderate and high RoB studies, respectively. The dose-response curve based on a one-stage cubic spline regression model showed an almost linear positive relation between exposure and SF occurrence starting from relatively low concentrations up to 5 mg/L and 2.5 mg/L, respectively, for water and urinary fluoride, with no substantial increase above this threshold. The RR for developing moderate-severe forms increases at 5.00 mg/L and 2.5 mg/L of water and urinary fluoride, respectively. Better-quality studies are needed to confirm these results, but greater attention should be given to water fluoride levels to prevent SF, in addition to the other potential adverse effects of fluoride exposure.
Topics: Humans; Fluorides; Fluorosis, Dental; Drinking Water; Prevalence
PubMed: 37861949
DOI: 10.1007/s40572-023-00412-9 -
Cancer Gene Therapy Jun 2023Chimeric Antigen Receptor (CAR) T cell therapy is an effective treatment approach for patients with relapsed or refractory acute lymphoblastic leukemia (R/R B-ALL).... (Meta-Analysis)
Meta-Analysis
Long-term response to autologous anti-CD19 chimeric antigen receptor T cells in relapsed or refractory B cell acute lymphoblastic leukemia: a systematic review and meta-analysis.
Chimeric Antigen Receptor (CAR) T cell therapy is an effective treatment approach for patients with relapsed or refractory acute lymphoblastic leukemia (R/R B-ALL). However, identifying the factors that influence long-term response to this therapy is necessary to optimize patient selection and treatment allocation. We conducted a literature review and meta-analysis to investigate the use of autologous anti-CD19 CAR T cell therapy in both pediatric and adult patients with R/R B-ALL, using several databases including MEDLINE, Cochrane Central, ScienceDirect, Web of Science, Journals@Ovid, Embase, and clinicaltrial.gov. A total of 38 reports were analyzed, which enrolled 2134 patients. Time-to-event endpoints were estimated using reconstructed patient survival data. The study explored key modulators of response, including costimulatory domains, disease status, age, and lymphodepletion. The median overall survival and event-free survival were 36.2 months [95% CI 28.9, NR] and 13.3 months [95% CI 12.2, 17], respectively. The overall response rate was 76% [95% CI 71, 81]. The use of 4-1BB costimulatory domain in the CAR construct, administration of low-dose cyclophosphamide lymphodepletion, and pretreatment morphologic remission were associated with better overall survival, with hazard ratios of 0.72, 0.56, and 0.66, respectively. Morphologic remission and 4-1BB domain were associated with better event-free survival, with hazard ratios of 0.66 and 0.72, respectively. These findings suggest that CAR T cell therapy may offer long-term benefits to patients with R/R B-ALL. However, further research is needed to optimize patient selection and better understand the impact of various factors on the outcome of CAR T cell therapy.
Topics: Adult; Humans; Child; Receptors, Chimeric Antigen; Receptors, Antigen, T-Cell; Immunotherapy, Adoptive; Precursor Cell Lymphoblastic Leukemia-Lymphoma; Antigens, CD19; T-Lymphocytes
PubMed: 36750666
DOI: 10.1038/s41417-023-00593-3