Impaired Microvascular Reactivity in Patients with Chronic Kidney Disease Submitted to Kidney Transplantation: A Prospective Observational Study.

INTRODUCTION: The effect of kidney transplantation on endothelial dysfunction and autonomic dysfunction in uremia remains controversial, and few studies have evaluated this question. Endothelial dysfunction and autonomic dysfunction, both, be assessed noninvasively using laser Doppler flowmetry (LDF). This study evaluated cutaneous microvascular blood flow and reactivity using LDF in patients undergoing kidney transplantation. METHODS: This prospective longitudinal cohort study involved 40 patients with chronic kidney disease (CKD) undergoing kidney transplantation, compared with 40 patients without kidney disease. Using LDF, post-occlusive reactive hyperemia (PORH) (resting flow [RF], peak flow, ratio between peak, and RF, hyperemic area, PORH index), and sympathetic constrictor response to inspiratory breath-hold (mean minimum inspiratory values) were evaluated. RESULTS: RF and sympathetic constrictor response to inspiratory breath-hold (mean minimum inspiratory values), were lower in the CKD group at 1 week and at 3 months after transplantation (p < 0.005). Mean minimum inspiratory values increase in the CKD group, 3 months after transplantation. CONCLUSION: Compared with controls with no CKD, in CKD patients undergoing kidney transplantation, microcirculation by LDF shows improvement after 3 months.

The Corrosive Effects of Aftermarket Oil Additives on High-Leaded Tin Bronze Alloy.

Aftermarket additives are used to enhance the performance of internal combustion engines in specific aspects such as reducing wear, increasing power, and improving fuel economy. Despite their advantages, they can sometimes cause corrosion-related problems. This research evaluated the corrosiveness of four aftermarket additives on the corrosion of a high-leaded tin bronze alloy over 28 days at 80 °C in immersion tests. Among the evaluated products, three showed corrosive effects ranging from intermediate to severe. Notably, the visual appearance of the surfaces often did not indicate the underlying corrosive damage. Therefore, the assessment of corrosiveness was based on chemical characterizations conducted on both the drained oils and the bronze surfaces. The study found minimal oil degradation under the testing conditions, indicating that the primary cause of corrosion was the interaction between the specific additives and the metal elements of the alloy, rather than oil degradation itself. A direct correlation was observed between the dissolution of lead and copper and the adsorption of S and Cl-containing additives on the surfaces, respectively. The corrosive impact of Cl-containing additives in aftermarket formulations was significantly reduced when mixed with engine oil SAE 10W-30 (at a 25:1 ratio), suggesting a mitigated effect in combined formulations, which is the recommended usage for engines.

Vaccination hesitation in children under five years of age: a scoping review.

OBJECTIVES: to synthesize scientific evidence on vaccine hesitancy in children under five years of age and its associated factors. METHODS: a scoping review, conducted according to the methodological structure proposed by the JBI. Searches were carried out in the Latin American and Caribbean Center on Health Sciences Information, Scientific Electronic Library Online and PubMed databases, including gray literature. Studies in English, Spanish and Portuguese were included, without temporal delimitation. Editorials, studies that did not address vaccine hesitancy in children under five years of age and were not aligned with the objective and research question were excluded. The sample consisted of 18 articles. RESULTS: misinformation, concern about adverse effects, distrust about efficacy, affliction regarding administration simultaneously, and insecurity in relation to the laboratories were the reported reasons. CONCLUSIONS: strategies are needed to combat the lack of information about immunobiological agents, as misinformation was the main factor in parents' vaccine hesitation.

Development of a Melting-Curve-Based Multiplex Real-Time PCR Assay for the Simultaneous Detection of Viruses Causing Respiratory Infection.

The prompt and accurate identification of the etiological agents of viral respiratory infections is a critical measure in mitigating outbreaks. In this study, we developed and clinically evaluated a novel melting-curve-based multiplex real-time PCR (M-m-qPCR) assay targeting the RNA-dependent RNA polymerase (RdRp) and nucleocapsid phosphoprotein N of SARS-CoV-2, the Matrix protein 2 of the Influenza A virus, the RdRp domain of the L protein from the Human Respiratory Syncytial Virus, and the polyprotein from Rhinovirus B genes. The analytical performance of the M-m-qPCR underwent assessment using in silico analysis and a panel of reference and clinical strains, encompassing viral, bacterial, and fungal pathogens, exhibiting 100% specificity. Moreover, the assay showed a detection limit of 10 copies per reaction for all targeted pathogens using the positive controls. To validate its applicability, the assay was further tested in simulated nasal fluid spiked with the viruses mentioned above, followed by validation on nasopharyngeal swabs collected from 811 individuals. Among them, 13.4% (109/811) tested positive for SARS-CoV-2, and 1.1% (9/811) tested positive for Influenza A. Notably, these results showed 100% concordance with those obtained using a commercial kit. Therefore, the M-m-qPCR exhibits great potential for the routine screening of these respiratory viral pathogens.

Impact of the number of players on the emergence of creative movements in small-sided soccer games: a systematic review emphasizing deliberate practice.

Introduction: Creativity is a recognized quality in various areas, including sports. Within the training processes, various modifications to objectives, game configurations, rules, among other factors, can be considered to favor creative solutions to the tactical problems inherent to soccer. This systematic review aimed to identify the impact of the number of players on the emergence of creative movements in small-sided soccer games, emphasizing deliberate practice. Methods: A systematic review of Scopus, PubMed, Scielo, PsycInfo, SportDiscus and Lilacs databases was performed according to PRISMA guidelines. Eligibility criteria were defined based on the elements of population, context and concept. Only full articles published in scientific journals written in English were included. No period restriction was applied. Results: Five papers were included and the results of studies indicate greater number of actions, variability, and creativity in small-sided games compared to formal soccer matches. When comparing different small-sided game formats, 5 v 5 showed higher values in terms of total number of actions compared to 7 v 7, and the absolute number of original and creative actions tended to decrease as the game format increased. Imbalanced small-sided games format can promote increased exploratory behavior. Structural manipulation in goal positioning in 5 v 5 games may also influence the originality of tactical behaviors, while the use of different ball types in 4 v 4 games appears to decrease fluency values. In 6 v 6 games, fluency and versatility are negatively impacted. Conclusion: Reduced game formats with fewer players and in smaller field dimensions provide more suggestive environment for exploratory behavior, variability and original and creative actions. The protocol was registered on the Open Science Framework (OSF) on 2 December 2022 (DOI: 10.17605/OSF.IO/VN6YZ). Systematic review registration: [https://osf.io/jmf4k/].

Sexual exposure to HIV in Angolan men who have sex with men immigrants: A cross-sectional study in Portugal and Brazil.

BACKGROUND: In different contexts, international migrants are vulnerable to health disparities that increase the risk of HIV/AIDS exposure and continue to bear a significant burden of new virus infections in developed and developing countries. In this study, we sought to examine sexual practices and factors linked to HIV exposure among a sample of Angolan men who have sex with men (MSM) immigrants. METHODS: The study was conducted in two Portuguese-speaking countries, Brazil and Portugal, and involved 250 Angolan MSM immigrants between September 2020 and February 2021, using sampling methods to constitute the sample and the HIV Incidence Risk Index (HIRI) to define virus exposure risk. Odds ratio (OR) and adjusted odds ratio (aOR) were used to calculate the chances of higher HIRI index in the sample. RESULTS: Our results showed that 76.8% of participants presented a high HIRI index, influenced by the practice of chemsex (aOR: 4.26), having a known/repeated partner (aOR: 4.59), and engaging in passive sex without a condom in the last 30 days (aOR: 1.29) or 6 months (aOR: 1.98). CONCLUSIONS: It is crucial to focus on this vulnerable population and implement sexual health policies that integrate combined HIV prevention measures aimed at immigrant MSM.

Maturity-associated variation in the body size, physical fitness, technical efficiency, and network-based centrality measures in young soccer players.

This study aimed to observe the relationships between the maturity status on the network-based centrality measures of young athletes in small-sided soccer games (SSG). The study included 81 male players (14.4 ± 1.1 years). Measurements included height, sitting height, body mass, and bone age (TW3 method). The applied protocols were the following: Countermovement Jump (CMJ), Yo-Yo Intermittent Recovery Test Level 1 (YYIRT1), Repeated Sprints Ability (RSA), observational analysis of techniques, and interactions performed by players in SSG. The relationship between the set of evaluated variables within each maturity status was obtained from the correlational analysis of networks (P < 0.05). The maturity status explained a significant portion of the variance in body mass (η2 = 0.37), height (η2 = 0.30), sitting height (η2 = 0.30), and performance on the YYIRT1 (η2 = 0.08), CMJ (η2 = 0.14), and RSA (η2 = 0.13). No effect of maturity status on network-based centrality measures of young athletes was identified (P > 0.05). For the late maturity group, there was a correlation between the degree of centrality and physical growth indicators (rmean = 0.88). For players with maturation "on time", physical growth indicators relate to the degree of prestige (rmean = 0.36). It is concluded that body size and bone age impact how late and on-time maturity groups interact within the match.

Relationship Between Body Size and Skeletal Age with Muscle Damage in Young Soccer Players.

This study verified the relationship between body size and skeletal age (SA) with the behavior of blood markers of muscle damage and delayed onset muscle soreness (DOMS) after a soccer match in the U-13 and U-15 categories. The sample consisted of 28 soccer players in the U-13 and 16 in the U-15 categories. Creatine kinase (CK), lactate dehydrogenase (LDH), and DOMS were evaluated up to 72 h after the match. Muscle damage was elevated at 0 h in U-13, and from 0 h to 24 h in U-15. DOMS increased from 0 h to 72 h in U-13 and from 0 h to 48 h in U-15. Significant associations of SA and fat-free mass (FFM) with muscle damage markers and DOMS were observed only in U-13, specifically at time 0 h, when SA explained 56% of CK and 48% of DOMS and FFM explained 48% of DOMS. We concluded that in the U-13 category, higher SA is significantly associated with muscle damage markers, and increase in FFM is associated with muscle damage markers and DOMS. Furthermore, U-13 players need 24 h to recover pre-match muscle damage markers and more than 72 h to recover DOMS. In contrast, the U-15 category needs 48 h to recover muscle damage markers and 72 h to recover DOMS.

Using Social Network Analysis to Study Relationships Between Young Soccer Players' Bone Age, Body Size, and the Centrality of Their Pass Interactions.

Prior research has suggested relevance to anthropometric variance of youth athletes at various stages of their maturation, and prior studies of youth players' soccer skills have failed to consider their interdependent interactions during play. Accordingly, to address both of these separate research omissions, we aimed in this study to analyze the relationships between young (U-13 and U-15 groups) soccer players' bone age and body size indicators and centrality measures of their pass interactions during small sided games. We included young 81 athletes (M age = 14.4, SD = 1.1 years) from whom we took anthropometric measurements of body mass, height, and trunk-cephalic height and obtained their bone age using the Tanner-Whitehouse 3 classification method. We also filmed small-sided games in the goal keeper/three player (GK3-3GK) format to analyze the centrality of their passing actions on the following measures: degree of centrality, closeness of centrality, degree of prestige, and proximity of prestige. There were no group differences in the prominence of passing actions across these three measures (tmean = -3.13; p > .05). Canonical correlations of these relationships were significant only in the U-13 group, in which centrality in passing actions was related to body size (r = 0.71; R2 = 0.21; ʌ = 0.28; p = .03). U-13 players who were physically larger and who presented higher bone age showed centralized main passing actions.

Body size, maturation and motor performance in young soccer players: relationship of technical actions in small-sided games.

The objective of this study was to investigate the relative contributions of body size, skeletal age, and motor performance variables with technical actions through an ecological model during small-sided soccer games, and the interaction of biological maturation with technical and motor performance in young players. In this cross-sectional study, eighty-two young players (14.4 ± 1.1 years), belonging to state-level soccer teams and divided by category (U-13 and U-15), were included. Players having an injury in the evaluation period were not included in the study. Measurements of body size, skeletal age (SA), motor tests, and technical actions in small-sided games (SSG) were performed (3 × 3 plus goalkeeper) in two periods (halves) of four minutes. Differences between age groups were found for SA (ES = -2.36), chronological age (ES = -3.89), body mass (ES = -2.09), height (ES = -1.90), and fat-free mass (ES = -2.09). Positive associations were found between body size (R = 0.43 to R = 0.48) and manipulation (R = 0.50 to R = 0.52) indicators and numbers of technical actions (CB and SS), except for stature with LB (R = -0.42) in the U-13 age group. In the U-15 category, skeletal age (R = -0.29 to R = -0.30) and body mass (R = -0.28 to R = -0.29) were negatively associated with the number of technical actions (RB, NB, LB, and OB) (P > 0.05) and positively with the balance with LB (R = 0.26). In conclusion, body size, SA, and motor performance influenced technical actions in SSG differentially in each category. U-13 heavier players and those with a better motor performance presented higher involvement due to the higher.

Vaccination hesitation in children under five years of age: a scoping review / Vacunación vacuna en niños menores de cinco años: una revisión del alcance / Hesitação vacinal em crianças menores de cinco anos: revisão de escopo

ABSTRACT Objectives: to synthesize scientific evidence on vaccine hesitancy in children under five years of age and its associated factors. Methods: a scoping review, conducted according to the methodological structure proposed by the JBI. Searches were carried out in the Latin American and Caribbean Center on Health Sciences Information, Scientific Electronic Library Online and PubMed databases, including gray literature. Studies in English, Spanish and Portuguese were included, without temporal delimitation. Editorials, studies that did not address vaccine hesitancy in children under five years of age and were not aligned with the objective and research question were excluded. The sample consisted of 18 articles. Results: misinformation, concern about adverse effects, distrust about efficacy, affliction regarding administration simultaneously, and insecurity in relation to the laboratories were the reported reasons. Conclusions: strategies are needed to combat the lack of information about immunobiological agents, as misinformation was the main factor in parents' vaccine hesitation.

RESUMEN Objetivos: sintetizar la evidencia científica sobre la reticencia vacunal en menores de cinco años y sus factores asociados. Métodos: revisión de alcance, realizada según la estructura metodológica propuesta por el JBI. Las búsquedas se realizaron en el Centro Latinoamericano y del Caribe de Información en Ciencias de la Salud, Scientific Electronic Library Online y PubMed, incluida la literatura gris. Se incluyeron estudios en inglés, español y portugués, sin delimitación temporal. Se excluyeron editoriales, estudios que no abordaran la reticencia vacunal en menores de cinco años y que no estuvieran alineados con el objetivo y pregunta de investigación. La muestra estuvo compuesta por 18 artículos. Resultados: la desinformación, la preocupación por los efectos adversos, la desconfianza en la eficacia, la angustia por la administración simultánea y la inseguridad por los laboratorios fueron los motivos informados. Conclusiones: se necesitan estrategias para combatir la falta de información sobre inmunobiológicos, ya que la desinformación fue el principal factor en la duda vacunal de los padres.

RESUMO Objetivos: sintetizar evidências científicas sobre hesitação vacinal em crianças menores de cinco anos e seus fatores associados. Métodos: revisão de escopo, conduzida conforme a estrutura metodológica proposta pelo JBI. Realizaram-se buscas nas bases Centro Latino-Americano e do Caribe de Informação em Ciências da Saúde, Scientific Electronic Library Online e PubMed, incluindo literatura cinzenta. Foram incluídos estudos em inglês, espanhol e português, sem delimitação, temporal. Foram excluídos editoriais, estudos que não abordaram hesitação vacinal em menores de cinco anos e não estiveram alinhadas com o objetivo e questão de pesquisa. A amostra foi composta por 18 artigos. Resultados: desinformação, preocupação com efeitos adversos, desconfiança sobre eficácia, aflição quanto à administração simultaneamente e insegurança em relação aos laboratórios foram os motivos relatados. Conclusões: são necessárias estratégias de combate à carência de informações acerca dos imunobiológicos, pois a desinformação foi o fator principal na hesitação vacinal dos pais.

Desafios dos laboratórios públicos da área de saúde ambiental para implantação e manutenção dos requisitos de normativas da qualidade para monitoramento da água de consumo humano / Challenges for public laboratories in the environmental health area for implementation and maintenance of quality regulatory requirements for monitoring human consumption water

Resumo Introdução O Ministério da Saúde (MS) é responsável pela vigilância da qualidade da água de consumo humano. A confiabilidade nos resultados do monitoramento de parâmetros analíticos minimiza riscos à saúde pública. Objetivo Retratar aspectos funcionais, a aplicação de ferramentas da qualidade e a aderência dos laboratórios públicos que atuam no monitoramento da água de consumo humano aos requisitos da norma ABNT NBR ISO/IEC 17025. Método A pesquisa foi realizada com 30 laboratórios públicos de todas as regiões do país, respondendo a um questionário elaborado com 49 perguntas sobre a formação e capacidade dos profissionais, garantia da validade dos resultados e sobre a determinação de parâmetros da qualidade da água. Resultados Dos 161 profissionais, 46% possuem mais de 10 anos de experiência e 65% têm formação superior. Capacitações específicas foram requeridas por todos. A validação dos métodos analíticos não foi realizada por 59%. Materiais de referência certificados são acessados por 41% e apenas 18% têm facilidade em adquiri-los. A participação em ensaios de proficiência foi reportada por 68% dos laboratórios, mas com poucos parâmetros avaliados e dificuldades em contratar provedores. Conclusão Evidenciou-se a necessidade de ações para fortalecimento da metrologia em laboratórios públicos que atuam na vigilância da qualidade da água.

Abstract Background The Ministry of Health (MS) is responsible for drinking water quality surveillance. Reliability in the results of monitoring analytical parameters minimizes public health risks. Objective To present functionals aspects and the application of quality tools by public laboratories that work to monitor the quality of drinking water. Method A survey was conducted with 30 public laboratories from all regions of the country, answering a questionnaire elaborated with 49 questions about the training and capacity of professionals, guaranteeing the validity of the results and about the determination of basic parameters of water quality. Results Of the 161 professionals, 46% have more than 10 years of experience and 65% have higher education. Specific training was required by everyone. The validation of the analytical methods was not performed by 59%. Reference materials are accessed by 41% and only 18% can acquire them easily. Participation in proficiency tests was reported by 68% of the laboratories, but with few parameters evaluated and difficulties in hiring providers. Conclusion The need for actions to strengthen metrology in public laboratories that work in water quality surveillance was highlighted.

Combined effect of game position and body size on network-based centrality measures performed by young soccer players in small-sided games.

This study verified the effects of body size and game position on interactions performed by young soccer players in small-sided games (SSG). The sample consisted of 81 Brazilian soccer players (14.4 ± 1.1 years of age). Height, body mass, and trunk-cephalic height were measured. SSG was applied in the GK + 3v3 + GK format, and Social Network Analyses were carried out through filming the games to obtain the following prominence indicators: degree centrality, closeness centrality, degree prestige, and proximity prestige, in addition to network intensity and number of goals scored. Factorial ANCOVA (bone age as covariate) was used to test the effects of game position, body size, and respective interaction on centrality measurements (p < 0.05). Similarity between game positions in body size indicators (p > 0.05) was observed. The game position affected degree centrality (p = 0.01, η 2 = 0.16), closeness centrality (p = 0.01, η 2 = 0.11), and network intensity (p = 0.02, η 2 = 0.09), in which midfielders presented the highest network prominence values when compared to defenders and forwards. In conclusion, midfielders are players with high interaction patterns in the main offensive plays, which behavior is independent of body size.

Adaptation and Validation of a Test for the Evaluation of Tactical Knowledge in Soccer: Test de Conocimiento Táctico Ofensivo en Fútbol for the Brazilian Context (TCTOF-BRA).

Background: Studies and tests to assess the tactical domain of young soccer players are recent, and few instruments meet the majority of quality criteria. Objective: To adapt and validate the Test de Conocimiento Táctico Ofensivo en Fútbol (TCTOF) for the Brazilian context (TCTOF-BRA). Methods: The article consists of two studies. Study 1 (n = 111) included the translation, theoretical/semantic analysis, back translation, cross-cultural equivalence, and content and face validity (pre-test). In study 2 (n = 768), a theoretical and empirical item analysis was carried out, followed by construct validity [exploratory factor analysis (EFA), confirmatory factor analysis (CFA), and the known-groups method] and reliability (internal consistency and repeatability). Results: In the cross-cultural evaluation, the Coefficient of content validity total (CCVt) of the instrument was 0.96 and in the content validity, the CCVt of the instrument was 0.87. The face validity was confirmed (>95%). After theoretical and empirical analysis, 15 questions were included in the Teste de Conhecimento Tático Ofensivo no Futebol (TCTOF-BRA). The EFA showed a model with adequate fit (KMO = 0.69; Bartlett p < 0.001), with a factor structure considered very good, composed of four factors (decision making, operational tactical principles, collective tactical-technical elements, and rules). The CFA by the Asymptotically Distribution-Free estimation method demonstrated good and very good goodness of fit indices (X 2/df = 1.54, GFI = 0.99, CFI = 0.94, TLI = 0.92, PGFI = 0.71, PCFI = 0.76, RMSEA = 0.03, and ECVI = 0.26). The known-groups method showed significant differences (p < 0.01) and effect sizes varying from small-to-medium to large. With respect to reliability, coefficients of 0.89 (CR) and 0.74 (KR20) for internal consistency and 0.85 for repeatability were found. Conclusion: The TCTOF-BRA presented satisfactory evidence, demonstrating it to be an instrument with valid and reliable measures for the evaluation of tactical knowledge (declarative and theoretical procedural), based on specific knowledge and decision making (cognitive domain), of Brazilian young soccer players from 12 to 17.9 years old.

The bioactive constituents and antioxidant activities of ten selected Brazilian Cerrado fruits.

This study measured the total levels of phenolic, anthocyanin, carotenoid, and tocopherol compounds, and vitamin C in ten fruits from the Brazilian Cerrado: araçá-boi, bacaba, bacupari, biribá, cajuí, curriola, marmelada-espinho, mirindiba, murici, and puçá-preto. Five extracts were prepared from each fruit using solvents with different polarities. The Trolox equivalent antioxidant activity, oxygen radical absorbance capacity, and inhibition of ß-carotene bleaching were determined for each extract. Scott-Knott test and principal component analysis showed that the analyzed fruits were rich sources of different classes of bioactive compounds, with levels comparable to those in commonly consumed fruits such as guavas, and various berries and citrus fruits. To our knowledge, this is the first comprehensive study of the bioactive compounds and antioxidant activities of biribá, cajuí, marmelada-espinho, and mirindiba. Moreover, mirindiba was found to be a rich source of vitamin C and phenolics, with an average level of carotenoids and tocopherols.

Effect of Non-Calcined Sugarcane Bagasse Ash as an Alternative Precursor on the Properties of Alkali-Activated Pastes.

BFS-MK-based alkali-activated materials are well established as an alternative for sustainable and green construction. This work aims to collaborate and encourage the use of biomass ashes, such as sugarcane bagasse ash (SCBA), as a precursor in alkali-activated materials (AAM). This ash is a rich source of aluminosilicate, which is a primary requirement for this application. In addition, this waste is still an environmental liability, especially in developing countries, and with a large volume of annual production. Thus, in this research, alkali-activated pastes (AA) were produced using sugarcane bagasse ash (SCBA), granulated blast furnace slag (BFS) and metakaolin (MK) as precursors. In addition, environmental gains were encouraged with energy savings, with no extra reburn or calcination steps in the SCBA. Thus, the precursors were characterized by laser granulometry, X-ray fluorescence spectrometry (XRF), X-ray diffraction (XRD), scanning electron microscopy (SEM) and Fourier transform infrared spectroscopy (FTIR). The pastes were produced by mixing the precursors with the activator, composed of a mixture of sodium hydroxide 8 mol/L and sodium silicate. Aiming to study the incorporation of SCBA, all samples have a precursor/activator ratio and a BFS/(BFS + MK) ratio constant of 0.6. The compressive strength analysis, FTIR, XRD, TGA, SEM and isothermal calorimetry analyses pointed out the occurrence of alkaline activation in all proposed samples for curing times of 7, 28 and 91 days. The sample GM0.6-BA0 (15% SCBA) achieved the highest compressive strength among the samples proposed (117.7 MPa, at 91 days), along with a good development of strength throughout the curing days. Thus, this work presents the properties of alkaline-activated pastes using SCBA as a sustainable and alternative precursor, seeking to encourage the use of raw materials and alternative waste in civil construction.

Markers of mitochondrial energy metabolism and their potential relationships with fatigue in human adults: a scoping review

This scoping review aimed to synthesize the best available evidence of the associations between molecular and genetic markers of mitochondrial metabolism and fatigue in human adults. The research question guiding this review was, "Are there potential relationships between mitochondrial metabolism markers and fatigue?" The literature search used three terms (mitochondria; fatigue; energy metabolism), which yielded 263 manuscripts and 22 theses/dissertations. The studies included in the review had to meet three criteria: (1) Include adult participants (≥18 years of age); (2) Show a relationship between mitochondrial energy metabolism and fatigue; (3) Be published in English, Spanish, or Portuguese. Of the 17 articles included for a full-text review, some had a cross-sectional design (6/17, 35%), and more than half (12/17, 70%) were published between 2015 and 2020. The predominant population studied were patients diagnosed with chronic fatigue syndrome (9/17, 53%). Most studies (15/17, 88%) assessed fatigue with validated instruments. Mitochondrial markers associated with fatigue are a) mitochondrial transport pathways and respiratory chain, b) mutations in mitochondrial DNA, and c) energy disorders in cells of the immune system, such as natural killer cells. Mitochondrial metabolic activities, such as the production and transport of ATP, are significant components that may help understand the etiology of fatigue. Future directions should include longitudinal study designs, characterization of fatigue phenotypes, and the identification of markers involved in production and transport pathways. The clinical relevance in this field can lead to interventions targeting mitochondrial markers to reduce or prevent fatigue.