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1.
BMC Cancer ; 24(1): 199, 2024 Feb 13.
Article in English | MEDLINE | ID: mdl-38347462

ABSTRACT

BACKGROUND: Glioblastoma (GBM) is an aggressive brain tumor that exhibits resistance to current treatment, making the identification of novel therapeutic targets essential. In this context, cellular prion protein (PrPC) stands out as a potential candidate for new therapies. Encoded by the PRNP gene, PrPC can present increased expression levels in GBM, impacting cell proliferation, growth, migration, invasion and stemness. Nevertheless, the exact molecular mechanisms through which PRNP/PrPC modulates key aspects of GBM biology remain elusive. METHODS: To elucidate the implications of PRNP/PrPC in the biology of this cancer, we analyzed publicly available RNA sequencing (RNA-seq) data of patient-derived GBMs from four independent studies. First, we ranked samples profiled by bulk RNA-seq as PRNPhigh and PRNPlow and compared their transcriptomic landscape. Then, we analyzed PRNP+ and PRNP- GBM cells profiled by single-cell RNA-seq to further understand the molecular context within which PRNP/PrPC might function in this tumor. We explored an additional proteomics dataset, applying similar comparative approaches, to corroborate our findings. RESULTS: Functional profiling revealed that vesicular dynamics signatures are strongly correlated with PRNP/PrPC levels in GBM. We found a panel of 73 genes, enriched in vesicle-related pathways, whose expression levels are increased in PRNPhigh/PRNP+ cells across all RNA-seq datasets. Vesicle-associated genes, ANXA1, RAB31, DSTN and SYPL1, were found to be upregulated in vitro in an in-house collection of patient-derived GBM. Moreover, proteome analysis of patient-derived samples reinforces the findings of enhanced vesicle biogenesis, processing and trafficking in PRNPhigh/PRNP+ GBM cells. CONCLUSIONS: Together, our findings shed light on a novel role for PrPC as a potential modulator of vesicle biology in GBM, which is pivotal for intercellular communication and cancer maintenance. We also introduce GBMdiscovery, a novel user-friendly tool that allows the investigation of specific genes in GBM biology.


Subject(s)
Glioblastoma , Prions , Humans , Gene Expression , Gene Expression Profiling , Glioblastoma/genetics , Glioblastoma/pathology , Prion Proteins/genetics , Prion Proteins/metabolism , Prions/genetics , Prions/metabolism , rab GTP-Binding Proteins/genetics , Synaptophysin/metabolism
2.
Int J Sports Med ; 2023 Aug 07.
Article in English | MEDLINE | ID: mdl-37549884

ABSTRACT

This study aimed to investigate the recovery of neuromuscular performance using mechanical parameters collected during jump (vertical and horizontal) and strength-power exercises in youth soccer players after official soccer matches. Twenty-one outfield highly trained youth male soccer athletes (age: 18.23 ± 0.73 years; weight: 72.12 ± 6.99 kg; height: 1.78 ± 0.08 m) from two teams competing in the 1st division of U-19 Portuguese National Championship participated in this study. Players completed a battery of physical tests at -2h, +30 min, +24h, and +48h in relation to the match. Countermovement jump height, horizontal jump distance, and bar velocity during the half-squat, bench press, and hip-thrust exercises, at fixed loads, were recorded. Countermovement jump was impaired until 24h post-match (-1.7% from pre to 24h post, p=0.050; ES=-0.82). Half-squat bar velocity was reduced immediately following the match (-6.8 % from pre- p=0.004; ES=-0.64) but recovered at +24h (+2.9%, p=1.00; ES=0.02). Hip-thrust bar velocity was reduced for up to 48h post-match (-7.4% from pre to 48h post, p<0.001; ES=-0.80). No impairments were found in the horizontal jump and bench press at any moment. Our findings show prolonged decrements in strength of the posterior chain following a soccer match, measured in the hip-thrust exercise, while the other exercises displayed faster recovery dynamics.

3.
PLoS One ; 18(7): e0289374, 2023.
Article in English | MEDLINE | ID: mdl-37523395

ABSTRACT

The aims of this study were to: (i) analyse the within-microcycle variations in professional soccer players; (ii) analyse the relationships between wellness and training and match load demands; (iii) analyse the relationships between match-day (MD) demands and wellness during the following day (MD+1); and (iv) analyse the relationships between MD and wellness during the day before match-play (MD-1). Thirteen professional soccer players (age: 24.85±3.13 years) were monitored daily over 16-weeks for wellness and training and match-play intensity. The daily wellness measures included fatigue, quality of sleep, muscle soreness, mood and stress using a 1-5 scale. Internal intensity was subjectively measured daily using the rating of perceived exertion (RPE) and the multiplication of RPE by session duration (s-RPE). While external intensity was quantified utilising high-speed running, sprinting, and acceleration and deceleration metrics. Data was analysed from each training session before (i.e., MD-5) or after the match (i.e., MD+1). Repeated measures ANOVA or Friedman ANOVA was used to analyse the aims (i) where Spearman correlation was applied to analyse the relationships between the aims (ii) and (iii) between sleep quality and training intensity. The main results for aim (i) showed that MD+1 presented the lowest values for wellness variables (p < 0.05). While MD-1 presented the lowest internal and external load values (for all variables), with MD presenting the highest values (p < 0.05). Regarding aim (ii), the main result showed significant large negative correlations between fatigue and s-RPE (r = -0.593; p = 0.033). Considering aim (iii), significant small to very large negative correlations were found for sleep quality, fatigue and muscle soreness with all internal and external variables (p < 0.05). Lastly, the main results for aim (iv) showed large negative correlations for fatigue and session duration; fatigue and s-RPE; muscle soreness and session duration; muscle soreness and s-RPE; and muscle soreness and decelerations (p < 0.05, for all). The main conclusions were that MD had an influence on wellness and internal and external training intensity, notably MD-1 and MD+1 were most affected. In this regard, a tendency of higher internal and external intensity on MD was associated with lower wellness measures of sleep quality, muscle soreness and fatigue on MD+1.


Subject(s)
Physical Conditioning, Human , Soccer , Humans , Male , Young Adult , Adult , Soccer/physiology , Physical Exertion/physiology , Myalgia , Health Status , Physical Conditioning, Human/physiology , Perception/physiology , Fatigue
4.
Nat Cell Biol ; 24(4): 579-589, 2022 04.
Article in English | MEDLINE | ID: mdl-35414020

ABSTRACT

Intercellular communication orchestrates a multitude of physiologic and pathologic conditions. Algorithms to infer cell-cell communication and predict downstream signalling and regulatory networks are needed to illuminate mechanisms of stem cell differentiation and tissue development. Here, to fill this gap, we developed and applied CellComm to investigate how the aorta-gonad-mesonephros microenvironment dictates haematopoietic stem and progenitor cell emergence. We identified key microenvironmental signals and transcriptional networks that regulate haematopoietic development, including Stat3, Nr0b2, Ybx1 and App, and confirmed their roles using zebrafish, mouse and human models. Notably, CellComm revealed extensive crosstalk among signalling pathways and convergence on common transcriptional regulators, indicating a resilient developmental programme that ensures dynamic adaptation to changes in the embryonic environment. Our work provides an algorithm and data resource for the scientific community.


Subject(s)
Hematopoietic Stem Cells , Zebrafish , Animals , Cell Differentiation , Hematopoiesis/physiology , Hematopoietic Stem Cells/metabolism , Mesonephros/metabolism , Mice , Zebrafish/genetics
5.
Article in English | MEDLINE | ID: mdl-35328871

ABSTRACT

The aim of this study was to verify and compare the effects of electromyostimulation training (EMS), strength training (ST), and both combined (STEMS), through the analysis of the elbow flexors muscle thickness. Forty subjects (24.45 ± 3.53 years), were randomly divided equally in 4 groups: 3 experimental groups and 1 control group. Each experimental group was submitted to one of three interventions, either an ST protocol, an EMS protocol, or a STEMS protocol. The control group (CG) did not perform any type of physical activity. Ultrasonography (US) was used to measure muscle thickness (MT) at 50 and 60% of the distance between the acromion and the olecranon. The results showed a significant difference in the elbow flexors muscle thickness after 8 weeks, both in the STG, EMSG, and STEMSG, but not in the CG. However, no significant differences were observed between the intervention protocols. It seems that an increase in MT can be obtained using either with ST, EMS, or both combined, however, the results doesn't support the overlap of one method in relation to the others. EMS can be another interesting tool to induce muscle hypertrophy, but not necessarily better.


Subject(s)
Electric Stimulation Therapy , Resistance Training , Electric Stimulation Therapy/methods , Exercise , Exercise Therapy/methods , Humans , Muscle Strength/physiology , Muscle, Skeletal/diagnostic imaging , Muscle, Skeletal/physiology , Young Adult
6.
Sci Rep ; 11(1): 24046, 2021 12 15.
Article in English | MEDLINE | ID: mdl-34911996

ABSTRACT

Microplastics (MPs) have gained a high degree of public interest since they are associated with the global release of plastics into the environment. Various studies have confirmed the presence of MPs throughout the food chain. However, information on the ingestion of MPs via the consumption of many commonly consumed foods like dairy products are scarce due to the lack of studies investigating the "contamination" of this food group by MPs. This lack of occurrence data is mainly due to the absence of robust analytical methods capable of reliably quantifying MPs with size < 20 µm in foods. In this work, a new methodology was developed to accurately determine and characterize MPs in milk-based products using micro-Raman (µRaman) technology, entailing combined enzymatic and chemical digestion steps. This is the first time that the presence of relatively low amounts of small-sized MP (≥ 5 µm) have been reported in raw milk collected at farm just after the milking machine and in some processed commercial liquid and powdered cow's milk products.

7.
Front Sports Act Living ; 3: 661200, 2021.
Article in English | MEDLINE | ID: mdl-34136806

ABSTRACT

Load is a multifactorial construct, but usually reduced to parameters of volume and intensity. In the last decades, other constructs have been proposed for assessing load, but also relying on relationships between volume and intensity. For example, Foster's Training Monotony has been used in athletes' load management simply by computing mean weekly load divided by its standard deviation, often multiplied by session rate of perceived exertion. Meanwhile, the Acute to Chronic Workload Ratio (ACWR) has been debated by the sport scientists as a useful monitoring metric and related to so-called injury prevention. None of these models includes parameters that are representative of training specificity, namely load orientation. The aim of this study is to present broader conceptual approaches translated by new indices for assessing Intraweek Training Monotony (ITM) and Acute to Chronic Workload Index (ACWI) while incorporating load orientation, session duration and weekly density (frequency normalized) in addition to parameters related to proxies of external and/or internal load. Our ITM and Foster's Training Monotony were similar in terms of average values, but very different for individualized analysis, illustrating how average values may be deceiving. While Foster's model provided clusters of values, ITM provided more scattered, individualized data. ACWI and ACWR provided very distinct qualitative information, and the two models were uncorrelated. Therefore, the models incorporating training load orientation presented in this study provide distinct and not redundant information when compared to previous models. More importantly, ITM and ACWI are metrics that are compatible to each other and might fit to coaches' monitoring targets in the short and medium terms, respectively. Because our models include several parameters, including load orientation, we contend that might provide a more complete monitoring tool. However, we suggest they are used for intraindividual comparisons and not so strongly for interindividual comparisons.

8.
Article in English | MEDLINE | ID: mdl-32635507

ABSTRACT

Indoor cycling's popularity is related to the combination of music and exercise leading to higher levels of exercise intensity. It was our objective to determine the efficacy of heart rate and rating of perceived exertion in controlling the intensity of indoor cycling classes and to quantify their association with oxygen uptake. Twelve experienced males performed three indoor cycling sessions of 45 min that differed in the way the intensity was controlled: (i) oxygen uptake; (ii) heart rate; and (iii) rating of perceived exertion using the OMNI-Cycling. The oxygen uptake levels were significantly higher (p = 0.007; µp2 = 0.254) in oxygen uptake than heart rate sessions. Oxygen uptake related to body mass was significantly higher (p < 0.005) in the oxygen uptake sessions compared with other sessions. Strong correlations were observed between oxygen uptake mean in the oxygen uptake and rating of perceived exertion sessions (r =0.986, p < 0.0001) and between oxygen uptake mean in the oxygen uptake and heart rate sessions (r = 0.977, p < 0.0001). Both heart rate and rating of perceived exertion are effective in controlling the intensity of indoor cycling classes in experienced subjects. However, the use of rating of perceived exertion is easier to use and does not require special instrumentation.


Subject(s)
Bicycling/physiology , Heart Rate/physiology , Oxygen Consumption/physiology , Physical Exertion/physiology , Adult , Exercise , Exercise Test , Female , Humans , Male
9.
Appl Environ Microbiol ; 83(19)2017 Oct 01.
Article in English | MEDLINE | ID: mdl-28754707

ABSTRACT

The human microbiome is a collection of microorganisms that inhabit every surface of the body that is exposed to the environment, generally coexisting peacefully with their host. These microbes have important functions, such as producing vitamins, aiding in maturation of the immune system, and protecting against pathogens. We have previously shown that a small-molecule extract from the human fecal microbiome has a strong repressive effect on Salmonella enterica serovar Typhimurium host cell invasion by modulating the expression of genes involved in this process. Here, we describe the characterization of this biological activity. Using a series of purification methods, we obtained fractions with biological activity and characterized them by mass spectrometry. These experiments revealed an abundance of aromatic compounds in the bioactive fraction. Selected compounds were obtained from commercial sources and tested with respect to their ability to repress the expression of hilA, the gene encoding the master regulator of invasion genes in Salmonella We found that the aromatic compound 3,4-dimethylbenzoic acid acts as a strong inhibitor of hilA expression and of invasion of cultured host cells by Salmonella Future studies should reveal the molecular details of this phenomenon, such as the signaling cascades involved in sensing this bioactive molecule.IMPORTANCE Microbes constantly sense and adapt to their environment. Often, this is achieved through the production and sensing of small extracellular molecules. The human body is colonized by complex communities of microbes, and, given their biological and chemical diversity, these ecosystems represent a platform where the production and sensing of molecules occur. In previous work, we showed that small molecules produced by microbes from the human gut can significantly impair the virulence of the enteric pathogen Salmonella enterica Here, we describe a specific compound from the human gut that produces this same effect. The results from this work not only shed light on an important biological phenomenon occurring in our bodies but also may represent an opportunity to develop drugs that can target these small-molecule interactions to protect us from enteric infections and other diseases.

10.
Extremophiles ; 20(6): 875-884, 2016 Nov.
Article in English | MEDLINE | ID: mdl-27709303

ABSTRACT

The Antarctic soil microbial community has a crucial role in the growth and stabilization of higher organisms, such as vascular plants. Analysis of the soil microbiota composition in that extreme environmental condition is crucial to understand the ecological importance and biotechnological potential. We evaluated the efficiency of isolation and abundance of strict anaerobes in the vascular plant Deschampsia antarctica rhizosphere collected in the Antarctic's Admiralty Bay and associated biodiversity to metabolic perspective and enzymatic activity. Using anaerobic cultivation methods, we identified and isolated a range of microbial taxa whose abundance was associated with Plant Growth-Promoting Bacteria (PGPB) and presences were exclusively endemic to the Antarctic continent. Firmicutes was the most abundant phylum (73 %), with the genus Clostridium found as the most isolated taxa. Here, we describe two soil treatments (oxygen gradient and heat shock) and 27 physicochemical culture conditions were able to increase the diversity of anaerobic bacteria isolates. Heat shock treatment allowed to isolate a high percentage of new species (63.63 %), as well as isolation of species with high enzymatic activity (80.77 %), which would have potential industry application. Our findings contribute to the understanding of the role of anaerobic microbes regarding ecology, evolutionary, and biotechnological features essential to the Antarctic ecosystem.


Subject(s)
Bacteria, Anaerobic/isolation & purification , Industrial Microbiology , Microbiota , Poaceae/microbiology , Rhizosphere , Adaptation, Physiological , Antarctic Regions , Bacteria, Anaerobic/classification , Bacteria, Anaerobic/enzymology , Bacteria, Anaerobic/genetics , Cold Temperature , Soil Microbiology
11.
J Basic Microbiol ; 54(7): 644-9, 2014 Jul.
Article in English | MEDLINE | ID: mdl-24026770

ABSTRACT

Quorum sensing is a cell-cell signaling mechanism based on cell density and that involves the production of hormone-like molecules called autoinducers (AI). One of the most studied AIs has been termed AI-2, and its biosynthesis requires the enzyme encoded by luxS. We have previously described for the first time that Bacteroides species can produce molecules with AI-2 activity. In this study, we focus on the detection of luxS and its activity as the AI-2 synthase in Bacteroides species. The strains Bacteroides fragilis B3b and Bacteroides vulgatus ATCC 8482 were selected based on a positive phenotype for AI-2 production and the presence of a putative luxS in the genome, respectively. In order to identify the luxS gene, cloning and heterologous expression strategies were utilized. We demonstrate that both strains contain functional luxS orthologs that can complement AI-2 production in Escherichia coli.


Subject(s)
Bacterial Proteins/genetics , Bacteroides fragilis/genetics , Bacteroides/genetics , Biofilms/growth & development , Carbon-Sulfur Lyases/genetics , Gene Expression Regulation, Bacterial , Homoserine/analogs & derivatives , Amino Acid Sequence , Bacterial Proteins/metabolism , Bacteroides/metabolism , Bacteroides fragilis/metabolism , Carbon-Sulfur Lyases/metabolism , Conserved Sequence , Escherichia coli/genetics , Escherichia coli/metabolism , Genetic Complementation Test , Homoserine/biosynthesis , Lactones , Molecular Sequence Data , Quorum Sensing , Recombinant Proteins/genetics , Recombinant Proteins/metabolism , Sequence Alignment , Signal Transduction
12.
FEMS Immunol Med Microbiol ; 56(1): 48-55, 2009 Jun.
Article in English | MEDLINE | ID: mdl-19260960

ABSTRACT

Bacteroides fragilis is a minor component of the intestinal microbiota and the most frequently isolated from intra-abdominal infections and bacteremia. Previously, our group has shown that molecules involved in laminin-1 (LMN-1) recognition were present in outer membrane protein extracts of B. fragilis MC2 strain. One of these proteins was identified and showed 98% similarity to a putative B. fragilis plasminogen-binding protein precursor, deposited in the public database. Thus, the objective of this work was to overexpress and further characterize this novel adhesin. The ability of B. fragilis MC2 strain and purified protein to convert plasminogen into plasmin was tested. Our results showed that B. fragilis strain MC2 strain adhered to both LMN-1 and plasminogen and this adhesion was inhibited by either LMN-1 or plasminogen. Regarding the plasminogen activation activity, both the whole bacterial cell and the purified protein converted plasminogen into plasmin similar to streptokinase used as a positive control. Bacterial receptors that recognize plasminogen bind to it and enhance its activation, transforming a nonproteolytic bacterium into a proteolytic one. We present in vitro evidence for a pathogenic function of the plasminogen receptor in promoting adherence to laminin and also the formation of plasmin by B. fragilis.


Subject(s)
Bacterial Outer Membrane Proteins/metabolism , Bacteroides Infections/microbiology , Bacteroides fragilis/metabolism , Bacteroides fragilis/pathogenicity , Plasminogen Activators/metabolism , Bacterial Adhesion , Bacterial Outer Membrane Proteins/chemistry , Bacterial Outer Membrane Proteins/genetics , Bacteroides Infections/metabolism , Bacteroides fragilis/genetics , Chromatography, Affinity , Cloning, Molecular , DNA, Bacterial/analysis , Fibrinolysin/metabolism , Humans , Laminin/metabolism , Mass Spectrometry , Plasminogen/metabolism , Plasminogen Activators/chemistry , Plasminogen Activators/genetics , Sequence Analysis, DNA , Virulence
13.
Anaerobe ; 13(5-6): 244-8, 2007.
Article in English | MEDLINE | ID: mdl-17980633

ABSTRACT

Dialister pneumosintes has been indicated as a potentially new periodontopathic species. This study evaluated the prevalence of this microorganism in saliva and subgingival biofilm from subjects with different periodontal conditions. Subgingival biofilm and saliva samples from 48 subjects with periodontal health (PH) and 116 patients with chronic periodontitis (CP) were obtained. DNA was extracted from the samples and the presence of D. pneumosintes was determined by PCR. Differences in clinical parameters and frequency of D. pneumosintes between groups were sought by Mann-Whitney, Chi-square and Fisher's exact tests. Overall, D. pneumosintes was detected in 47.8% of the biofilm samples, but only in 3% of saliva samples. CP patients presented a significantly greater mean prevalence of this species in sites with periodontal health and periodontal infection (43.5+/-7.4% and 62.1+/-6.4%, respectively) than PH subjects (29.4+/-7.9%) (Mann-Whitney; p<0.01). Moreover, significant associations between the prevalence of D. pneumosintes and pocket depth (p=0.001), attachment loss (p=0.001) and bleeding on probing (GLM, p=0.014) were observed after adjusting for age and gender. These findings corroborate the association of D. pneumosintes with periodontitis.


Subject(s)
Biofilms/growth & development , Gram-Negative Bacterial Infections/microbiology , Periodontal Diseases/microbiology , Veillonellaceae/isolation & purification , Adult , DNA, Bacterial/analysis , Gingiva/microbiology , Humans , Periodontal Pocket/microbiology , Polymerase Chain Reaction , Veillonellaceae/physiology
14.
ACM arq. catarin. med ; 35(3): 82-86, jul.-out. 2006. tab
Article in Portuguese | LILACS | ID: lil-445503

ABSTRACT

Introdução: O abdome agudo consta de distúrbios subjetivos e de sinais objetivos cuja ocorrência não permite muitas vezes estabelecer um diagnóstico. As dificuldades em relação a um exame clínico que permita diagnóstico de certeza e a necessidade de intervenção com urgência constituem aspectos que demonstram a complexidade desta patologia.Objetivo: Correlacionar as variáveis: sexo, idade, síndrome do abdome agudo e etiologias da síndrome. Métodos: Foi realizado um estudo descritivo retrospectivo de 226 prontuários, no período de 01.01.2002 a 31.12.2004, no Hospital Universitário Pequeno Anjo, em Itajaí, SC. Resultados: O sexo mais acometido foi o masculino, com 68,6%; a idade mais acometida foi a da criança maior, com 86,3%; a síndrome inflamatória, com 73,5% acompanhada respectivamente pelas síndromes obstrutiva, hemorrágica e perfurativa. Conclusão: A síndrome inflamatória e a apendicite aguda foram respectivamente a síndrome e a etiologia mais freqüentes do abdome agudo; a síndrome obstrutiva apresentou o maior numero de etiologias e foi a síndrome mais freqüente até o primeiro ano de vida...


Subject(s)
Humans , Male , Female , Child , Abdomen, Acute , Child , Pediatrics , Surgical Procedures, Operative
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