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Work (Reading, Mass.) 2019Exposure to severe cold thermal environment (SCE) is a significant risk factor in the frozen food industry, influencing health and safety of the employees.
BACKGROUND
Exposure to severe cold thermal environment (SCE) is a significant risk factor in the frozen food industry, influencing health and safety of the employees.
OBJECTIVE
The aim of this work is to present the level of knowledge on the influence of SCE on core and skin temperatures.
METHODS
The review has been conducted using appropriated keywords and expressions, by searching 21 electronic databases and references of the included articles. Only research articles with healthy subjects and considering exposure to SCE conditions (- 5°C or lower) were considered.
RESULTS
Thirteen articles were included in the systematic review which met the research objective and were in accordance with the inclusion and exclusion criteria. All the included studies measured core or skin temperatures.
CONCLUSIONS
The main findings of this review indicate that working in SCE is and will remain an added risk factor. Further studies should be conducted in laboratory and industrial severe cold thermal environments on acclimatized and non-acclimatized subjects, in order to evaluate core and skin temperature variations and its recovery periods.
Topics: Acclimatization; Adult; Body Temperature Regulation; Cold Temperature; Female; Humans; Male; Skin Temperature
PubMed: 30829644
DOI: 10.3233/WOR-192868 -
Journal of Sports Sciences Jun 2022We estimated the effectiveness of using velocity feedback to regulate resistance training load on changes in muscle strength, power, and linear sprint speed in... (Meta-Analysis)
Meta-Analysis
Comparison of the effects of velocity-based vs. traditional resistance training methods on adaptations in strength, power, and sprint speed: A systematic review, meta-analysis, and quality of evidence appraisal.
We estimated the effectiveness of using velocity feedback to regulate resistance training load on changes in muscle strength, power, and linear sprint speed in apparently healthy participants. Academic and grey literature databases were systematically searched to identify randomised trials that compared a velocity-based training intervention to a 'traditional' resistance training intervention that did not use velocity feedback. Standardised mean differences (SMDs) were pooled using a random effects model. Risk of bias was assessed with the Risk of Bias 2 tool and the quality of evidence was evaluated using the GRADE approach. Four trials met the eligibility criteria, comprising 27 effect estimates and 88 participants. The main analyses showed trivial differences and imprecise interval estimates for effects on muscle strength (SMD 0.06, 95% CI -0.51-0.63; = 42.9%; 10 effects from 4 studies; low-quality evidence), power (SMD 0.11, 95% CI -0.28-0.49; = 13.5%; 10 effects from 3 studies; low-quality evidence), and sprint speed (SMD -0.10, 95% CI -0.72-0.53; = 30.0%; 7 effects from 2 studies; very low-quality evidence). The results were robust to various sensitivity analyses. In conclusion, there is currently no evidence that VBT and traditional resistance training methods lead to different alterations in muscle strength, power, or linear sprint speed.
Topics: Acclimatization; Adaptation, Physiological; Humans; Muscle Strength; Resistance Training
PubMed: 35380511
DOI: 10.1080/02640414.2022.2059320 -
Environmental Health Perspectives Dec 2011Heat-related mortality is a matter of great public health concern, especially in the light of climate change. Although many studies have found associations between high... (Review)
Review
BACKGROUND
Heat-related mortality is a matter of great public health concern, especially in the light of climate change. Although many studies have found associations between high temperatures and mortality, more research is needed to project the future impacts of climate change on heat-related mortality.
OBJECTIVES
We conducted a systematic review of research and methods for projecting future heat-related mortality under climate change scenarios.
DATA SOURCES AND EXTRACTION
A literature search was conducted in August 2010, using the electronic databases PubMed, Scopus, ScienceDirect, ProQuest, and Web of Science. The search was limited to peer-reviewed journal articles published in English from January 1980 through July 2010.
DATA SYNTHESIS
Fourteen studies fulfilled the inclusion criteria. Most projections showed that climate change would result in a substantial increase in heat-related mortality. Projecting heat-related mortality requires understanding historical temperature-mortality relationships and considering the future changes in climate, population, and acclimatization. Further research is needed to provide a stronger theoretical framework for projections, including a better understanding of socioeconomic development, adaptation strategies, land-use patterns, air pollution, and mortality displacement.
CONCLUSIONS
Scenario-based projection research will meaningfully contribute to assessing and managing the potential impacts of climate change on heat-related mortality.
Topics: Climate Change; Forecasting; Hot Temperature; Humans; Models, Theoretical; Research
PubMed: 21816703
DOI: 10.1289/ehp.1103456 -
Clinical & Translational Oncology :... Feb 2024Glioblastoma (GBM) constitutes the most common primary brain tumor in adults. The challenges in GBM therapeutics have shed light on zebrafish used as a promising animal... (Review)
Review
Glioblastoma (GBM) constitutes the most common primary brain tumor in adults. The challenges in GBM therapeutics have shed light on zebrafish used as a promising animal model for preclinical GBM xenograft studies without a standardized methodology. This systematic review aims to summarize the advances in zebrafish GBM xenografting, compare research protocols to pinpoint advantages and underlying limitations, and designate the predominant xenografting parameters. Based on the PRISMA checklist, we systematically searched PubMed, Scopus, and ZFIN using the keywords "glioblastoma," "xenotransplantation," and "zebrafish" for papers published from 2005 to 2022, available in English. 46 articles meeting the review criteria were examined for the zebrafish strain, cancer cell line, cell labeling technique, injected cell number, time and site of injection, and maintenance temperature. Our review designated that AB wild-type zebrafish, Casper transparent mutants, transgenic Tg(fli1:EGFP), or crossbreeding of these predominate among the zebrafish strains. Orthotopic transplantation is more commonly employed. A number of 50-100 cells injected at 48 h post-fertilization in high density and low infusion volume is considered as an effective xenografting approach. U87 cells are used for GBM angiogenesis studies, U251 for GBM proliferation studies, and patient-derived xenograft (PDX) to achieve clinical relevance. Gradual acclimatization to 32-33 °C can partly address the temperature differential between the zebrafish and the GBM cells. Zebrafish xenograft models constitute valuable tools for preclinical studies with clinical relevance regarding PDX. The GBM xenografting research requires modification based on the objective of each research team. Automation and further optimization of the protocol parameters could scale up the anticancer drug trials.
Topics: Animals; Humans; Glioblastoma; Transplantation, Heterologous; Zebrafish; Heterografts; Brain Neoplasms; Cell Line, Tumor; Xenograft Model Antitumor Assays; Disease Models, Animal
PubMed: 37400666
DOI: 10.1007/s12094-023-03258-7 -
Sports Medicine (Auckland, N.Z.) Nov 2016Exercise training (ExT) prompts multiple beneficial adaptations associated with vascular health, such as increases in skeletal muscle capillarization and vascular... (Meta-Analysis)
Meta-Analysis Review
BACKGROUND
Exercise training (ExT) prompts multiple beneficial adaptations associated with vascular health, such as increases in skeletal muscle capillarization and vascular dilator function and decreases in arterial stiffness. However, whether ExT performed in hypoxic conditions induces enhanced effects is unclear.
OBJECTIVE
We sought to systematically review the literature and determine whether hypoxic ExT leads to superior vascular adaptations compared with normoxic ExT.
METHODS
We searched MEDLINE, Scopus, and Web of Science from their inception until September 2015 for articles assessing vascular adaptations to ExT performed under hypoxic and normoxic conditions. We performed meta-analyses to determine the standardized mean difference (SMD) between the effects of ExT performed in hypoxia versus normoxia on vascular adaptations. We assessed heterogeneity among studies using I statistics and evaluated publication bias via the Begg and Mazumdar's rank correlation test and Egger's regression test.
RESULTS
After systematic review, we included 21 controlled studies, including a total of 331 individuals (mean age 19-57 years, 265 males). ExT programs primarily consisted of cycling endurance training performed in normobaric hypoxia or normoxia; duration ranged from 3 to 10 weeks. The exercise intensity was similar in relative terms in the groups trained in hypoxia and normoxia in the majority of studies (17 of 21). After data pooling, skeletal muscle capillarization (n = 182, SMD = 0.40, 95 % confidence interval [CI] 0.10-0.70; P = 0.01) and vascular dilator function (n = 71, SMD = 0.67, 95 % CI 0.17-1.18; P = 0.009) but not arterial stiffness (n = 112, SMD = -0.03, 95 % CI -0.69 to 0.63; P = 0.93), were enhanced with ExT performed in hypoxia versus normoxia. We only found heterogeneity among studies assessing arterial stiffness (I = 63 %, P = 0.02), and no publication bias was detected.
CONCLUSION
Based on current published studies, hypoxic ExT potentiates vascular adaptations related to skeletal muscle capillarization and dilator function. These findings may contribute to establishing effective exercise programs designed to enhance vascular health.
Topics: Acclimatization; Adult; Exercise; Humans; Hypoxia; Male; Middle Aged; Muscle, Skeletal; Oxygen Consumption; Vascular Stiffness; Young Adult
PubMed: 27286988
DOI: 10.1007/s40279-016-0570-5 -
Public Health May 2013Adaptation will be necessary to cope with the impacts of climate change on the health of Canadians. Civil society organizations (CSOs) have an important role in health... (Review)
Review
BACKGROUND
Adaptation will be necessary to cope with the impacts of climate change on the health of Canadians. Civil society organizations (CSOs) have an important role in health adaptation, but it is unknown what actions they are undertaking.
OBJECTIVES
To identify and examine what adaptations are being developed by CSOs to adapt to the health effects of climate change based on a systematic review of the activities of 190 organizations and 1196 reported adaptation actions.
RESULTS
There were six key findings: (1) health adaptation actions are predominantly led by environmental CSOs; (2) most actions are occurring at national and regional levels; (3) food and/or water contamination and air quality are dominant climate change stimuli for action; (4) responses predominantly reflect awareness and research activities, with limited evidence of substantive intervention; (5) consideration of vulnerable groups is limited; and (6) climate change is usually considered alongside other factors, if at all.
CONCLUSIONS
The results indicate a deficit in terms of what needs to be done for health adaptation and what is being done; part of a broader adaptation deficit in Canada. Coordinated adaptation planning at federal and provincial level is needed, involving collaboration between CSOs and public health bodies.
Topics: Acclimatization; Canada; Climate Change; Cooperative Behavior; Humans; Organizations; Public Health Practice
PubMed: 23583032
DOI: 10.1016/j.puhe.2013.02.004 -
Journal of Evolutionary Biology Jan 2023Temperatures are increasing due to global changes, putting biodiversity at risk. Organisms are faced with a limited set of options to cope with this situation: adapt,... (Meta-Analysis)
Meta-Analysis Review
Temperatures are increasing due to global changes, putting biodiversity at risk. Organisms are faced with a limited set of options to cope with this situation: adapt, disperse or die. We here focus on the first possibility, more specifically, on evolutionary adaptations to temperature. Ectotherms are usually characterized by a hump-shaped relationship between fitness and temperature, a non-linear reaction norm that is referred to as thermal performance curve (TPC). To understand and predict impacts of global change, we need to know whether and how such TPCs evolve. Therefore, we performed a systematic literature search and a statistical meta-analysis focusing on experimental evolution and artificial selection studies. This focus allows us to directly quantify relative fitness responses to temperature selection by calculating fitness differences between TPCs from ancestral and derived populations after thermal selection. Out of 7561 publications screened, we found 47 studies corresponding to our search criteria representing taxa across the tree of life, from bacteria, to plants and vertebrates. We show that, independently of species identity, the studies we found report a positive response to temperature selection. Considering entire TPC shapes, adaptation to higher temperatures traded off with fitness at lower temperatures, leading to niche shifts. Effects were generally stronger in unicellular organisms. By contrast, we do not find statistical support for the often discussed "Hotter is better" hypothesis. While our meta-analysis provides evidence for adaptive potential of TPCs across organisms, it also highlights that more experimental work is needed, especially for under-represented taxa, such as plants and non-model systems.
Topics: Animals; Climate Change; Temperature; Adaptation, Physiological; Hot Temperature; Acclimatization; Plants
PubMed: 36129955
DOI: 10.1111/jeb.14087 -
International Journal of Environmental... Sep 2021Several aspects of cognition can be affected after cold exposure, but contradictory results have been reported regarding affected cognitive domains. The aim of the... (Review)
Review
Several aspects of cognition can be affected after cold exposure, but contradictory results have been reported regarding affected cognitive domains. The aim of the current systematic review was to evaluate the effects of specific cold exposure on cognitive performance in healthy subjects. A systematic search was performed using MEDLINE (through PubMed), EMBASE (Scopus) and PsycINFO databases according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. Inclusion criteria were healthy subjects exposed to a cold environment (either simulated or not) and cognitive performance related to cold exposure with an experimental design. The literature search identified 18 studies, eight studies investigated the effect of cold air exposure and ten the effect of cold water immersion on cognitive performance of healthy subjects. There were several differences among the studies (environmental temperature reached, time of exposure, timing, and type of cognitive test administration). Cold exposure induced in most of the experimental settings (15 of 18) an impairment of CP even before accidental hypothermia was established. The most investigated and affected cognitive domains were attention and processing speed, executive function, and memory. Gender differences and effects of repeated exposure and possible acclimation on cognitive performance need further studies to be confirmed.
Topics: Acclimatization; Adult; Attention; Cognition; Cognitive Dysfunction; Executive Function; Humans
PubMed: 34574649
DOI: 10.3390/ijerph18189725 -
Neuromodulation : Journal of the... Jan 2024This systematic and meta-analysis review evaluated the transcutaneous electrical nerve stimulation (TENS)-induced action mechanisms for animal analgesia. (Meta-Analysis)
Meta-Analysis Review
OBJECTIVE
This systematic and meta-analysis review evaluated the transcutaneous electrical nerve stimulation (TENS)-induced action mechanisms for animal analgesia.
MATERIALS AND METHODS
Two independent investigators identified relevant articles published until February 2021 through a literature review, and a random-effects meta-analysis was performed to synthesize the results.
RESULTS
Of the 6984 studies found in the data base search, 53 full-text articles were selected and used in the systematic review. Most studies used Sprague Dawley rats (66.03%). High-frequency TENS was applied to at least one group in 47 studies, and most applications were performed for 20 minutes (64.15%). Mechanical hyperalgesia was analyzed as the primary outcome in 52.83% of the studies and thermal hyperalgesia in 23.07% of studies using a heated surface. More than 50% of the studies showed a low risk of bias on allocation concealment, random housing, selective outcome reporting, and acclimatization before the behavioral tests. Blinding was not performed in only one study and random outcome assessment in another study; acclimatization before the behavioral tests was not performed in just one study. Many studies had an uncertain risk of bias. Meta-analyses indicated no difference between low-frequency and high-frequency TENS with variations among the pain models.
CONCLUSIONS
This systematic review and meta-analysis suggests that TENS has presented a substantial scientific foundation for its hypoalgesic effect in preclinical studies for analgesia.
Topics: Rats; Animals; Transcutaneous Electric Nerve Stimulation; Rats, Sprague-Dawley; Pain; Pain Management; Hyperalgesia; Models, Animal
PubMed: 37115123
DOI: 10.1016/j.neurom.2023.02.085 -
Sports Medicine (Auckland, N.Z.) Sep 2014Hypoxic training techniques are increasingly used by athletes in an attempt to improve performance in normoxic environments. The 'live low-train high (LLTH)' model of... (Review)
Review
BACKGROUND AND OBJECTIVE
Hypoxic training techniques are increasingly used by athletes in an attempt to improve performance in normoxic environments. The 'live low-train high (LLTH)' model of hypoxic training may be of particular interest to athletes because LLTH protocols generally involve shorter hypoxic exposures (approximately two to five sessions per week of <3 h) than other traditional hypoxic training techniques (e.g., live high-train high or live high-train low). However, the methods employed in LLTH studies to date vary greatly with respect to exposure times, training intensities, training modalities, degrees of hypoxia and performance outcomes assessed. Whilst recent reviews provide some insight into how LLTH may be applied to enhance performance, little attention has been given to how training intensity/modality may specifically influence subsequent performance in normoxia. Therefore, this systematic review aims to evaluate the normoxic performance outcomes of the available LLTH literature, with a particular focus on training intensity and modality.
DATA SOURCES AND STUDY SELECTION
A systematic search was conducted to capture all LLTH studies with a matched normoxic (control) training group and the assessment of performance under normoxic conditions. Studies were excluded if no training was completed during the hypoxic exposures, or if these exposures exceeded 3 h per day. Four electronic databases were searched (PubMed, SPORTDiscus, EMBASE and Web of Science) during August 2013, and these searches were supplemented by additional manual searches until December 2013.
RESULTS
After the electronic and manual searches, 40 papers were deemed to meet the inclusion criteria, representing 31 separate studies. Within these 31 studies, four types of LLTH were identified: (1) continuous low-intensity training in hypoxia (CHT, n = 16), (2) interval hypoxic training (IHT, n = 4), (3) repeated sprint training in hypoxia (RSH, n = 3) and (4) resistance training in hypoxia (RTH, n = 4). Four studies also used a combination of CHT and IHT. The majority of studies reported no difference in normoxic performance between the hypoxic and normoxic training groups (n = 19), while nine reported greater improvements in the hypoxic group and three reported poorer outcomes compared with the control group. Selection of training intensity (including matching relative or absolute intensity between normoxic and hypoxic groups) was identified as a key factor in mediating the subsequent normoxic performance outcomes. Five studies included some form of normoxic training for the hypoxic group and 14 studies assessed performance outcomes not specific to the training intensity/modality completed during the training intervention.
CONCLUSION
Four modes of LLTH are identified in the current literature (CHT, IHT, RSH and RTH), with training mode and intensity appearing to be key factors in mediating subsequent performance responses in normoxia. Improvements in normoxic performance appear most likely following high-intensity, short-term and intermittent training (e.g., IHT, RSH). LLTH programmes should carefully apply the principles of training and testing specificity and include some high-intensity training in normoxia. For RTH, it is unclear whether the associated adaptations are greater than those of traditional (maximal) resistance training programmes.
Topics: Acclimatization; Athletic Performance; Exercise; Humans; Hypoxia; Physical Education and Training; Resistance Training; Running
PubMed: 24849544
DOI: 10.1007/s40279-014-0204-8