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1.
Sensors (Basel) ; 24(2)2024 Jan 14.
Artigo em Inglês | MEDLINE | ID: mdl-38257605

RESUMO

Our purpose was to characterize the oxygen uptake kinetics (VO2), energy systems contributions and total energy expenditure during a CrossFit® benchmark workout performed in the extreme intensity domain. Fourteen highly trained male CrossFitters, aged 28.3 ± 5.4 years, with height 177.8 ± 9.4 cm, body mass 87.9 ± 10.5 kg and 5.6 ± 1.8 years of training experience, performed the Isabel workout at maximal exertion. Cardiorespiratory variables were measured at baseline, during exercise and the recovery period, with blood lactate and glucose concentrations, including the ratings of perceived exertion, measured pre- and post-workout. The Isabel workout was 117 ± 10 s in duration and the VO2 peak was 47.2 ± 4.7 mL·kg-1·min-1, the primary component amplitude was 42.0 ± 6.0 mL·kg-1·min-1, the time delay was 4.3 ± 2.2 s and the time constant was 14.2 ± 6.0 s. The accumulated VO2 (0.6 ± 0.1 vs. 4.8 ± 1.0 L·min-1) value post-workout increased substantially when compared to baseline. Oxidative phosphorylation (40%), glycolytic (45%) and phosphagen (15%) pathways contributed to the 245 ± 25 kJ total energy expenditure. Despite the short ~2 min duration of the Isabel workout, the oxygen-dependent and oxygen-independent metabolism energy contributions to the total metabolic energy release were similar. The CrossFit® Isabel requires maximal effort and the pattern of physiological demands identifies this as a highly intensive and effective workout for developing fitness and conditioning for sports.


Assuntos
Benchmarking , Metabolismo Energético , Masculino , Humanos , Cinética , Exercício Físico , Oxigênio
2.
Caries Res ; 53(1): 33-40, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-29879720

RESUMO

The aim of this in vitro study was to investigate the impact of saliva on the abrasion of eroded enamel using two measuring methods. A total of 80 bovine enamel specimens from 20 bovine incisors were allocated to four experimental groups (n = 20 specimens per group). After baseline surface microhardness (SMH) measurements and profilometry all specimens were subjected to erosion (2 min, 1% citric acid, pH: 3.6, 37°C). SMH was determined again, and the depths of the Knoop indentations were calculated. Thereafter, specimens were incubated in human saliva (group 1 - no incubation/control, group 2 - 0.5 h, group 3 - 1 h, group 4 - 2 h) before toothbrush abrasion was performed. After final SMH measurements and profilometry, indentations were remeasured, and surface loss was calculated. SMH did not return to baseline values regardless of the length of saliva incubation. Further, an irreversible substance loss was observed for all specimens. With the indentation method, significantly (p < 0.05) more substance loss was found for controls (least square means ± standard error of 198 ± 19 nm) than for groups 2-4 (110 ± 10, 114 ± 11, and 105 ± 14 nm). Profilometric assessment showed significantly more substance loss for controls (122 ± 8 nm) than for group 4 (106 ± 5 nm). Intraclass correlation for interrater reliability between measurement methods was low (0.21, CI: 0.1-0.3), indicating poor agreement. Exposure of eroded enamel to saliva for up to 2 h could not re-establish the original SMH. The amount of measured substance loss depended on the measurement method applied.


Assuntos
Esmalte Dentário/fisiopatologia , Dureza/efeitos dos fármacos , Saliva/química , Abrasão Dentária/induzido quimicamente , Erosão Dentária/induzido quimicamente , Animais , Bovinos , Ácido Cítrico/efeitos adversos , Dureza/fisiologia , Humanos , Reprodutibilidade dos Testes , Propriedades de Superfície/efeitos dos fármacos , Remineralização Dentária , Escovação Dentária
3.
Fish Physiol Biochem ; 44(1): 143-162, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-28900838

RESUMO

Jatropha seed cake (JSC) is an excellent source of protein but does contain some antinutritional factors (ANF) that can act as toxins and thus negatively affect the growth and health status of fish. While this can limit the use of JSC, detoxified Jatropha protein isolate (DJPI) may be a better option. An 8-week study was performed to evaluate dietary DJPI to common carp Cyprinus carpio. Five iso-nitrogenous diets (crude protein of 38%) were formulated that consisted of a C ontrol (fish meal (FM) based protein), J 50 or J 75 (50 and 75% of FM protein replaced by DJPI), and S 50 or S 75 (50 and 75% of FM protein replaced by soy protein isolate, SPI) and fed to triplicate groups of 75 carp fingerlings (75; av. wt. ± SD; 11.4 ± 0.25 g). The growth, feeding efficiencies, digestibility, plasma biochemistry, and intestinal enzymes were measured. Results showed that growth performance of fish fed the S 75- or DJPI-based diets were not significantly different from those fed the C ontrol diet, while carp fed the S 50 had significantly better growth than the J 75 diet. Fish fed the J 75 diet had significantly lower protein and lipid digestibility as well as significantly lower intestinal amylase and protease activities than all other groups. However, all plant protein-based diets led to significantly higher crude protein, crude lipid, and gross energy in the body of common carp compared to the control treatment. Plasma cholesterol and creatinine significantly decreased in the plant protein fed groups, although plasma triglyceride as well as the red blood cells count, hematocrit, albumin, globulin, total plasma protein, and lysozyme activity were higher in plant protein fed groups compared to FM fed group. White blood cells, hemoglobulin concentration, alkaline phosphatase and alanine transaminase activities, and glucose level in blood did not differ significantly among treatments. The results suggest that the DJPI is non-toxic to carp and can be used to replace FM in the diets of common carp up to 75%, but further research to potentially reduce some inherent ANF within this protein source, such as non-starch polysaccharides, may improve nutrient utilization.


Assuntos
Carpas , Proteínas Alimentares , Glycine max , Jatropha/química , Proteínas de Plantas , Ração Animal/análise , Fenômenos Fisiológicos da Nutrição Animal , Animais , Colesterol/sangue , Dieta/veterinária , Digestão/fisiologia , Metabolismo Energético , Valor Nutritivo , Triglicerídeos/sangue
4.
J Cell Biochem ; 118(4): 764-774, 2017 04.
Artigo em Inglês | MEDLINE | ID: mdl-27632380

RESUMO

The epigenetics and molecular biology of human embryonic stem cells (hES cells) have received much more attention than their architecture. We present a more complete look at hES cells by electron microscopy, with a special emphasis on the architecture of the nucleus. We propose that there is an ultrastructural signature of pluripotent human cells. hES cell nuclei lack heterochromatin, including the peripheral heterochromatin, that is common in most somatic cell types. The absence of peripheral heterochromatin may be related to the absence of lamins A and C, proteins important for linking chromatin to the nuclear lamina and envelope. Lamins A and C expression and the development of peripheral heterochromatin were early steps in the development of embryoid bodies. While hES cell nuclei had abundant nuclear pores, they also had an abundance of nuclear pores in the cytoplasm in the form of annulate lamellae. These were not a residue of annulate lamellae from germ cells or the early embryos from which hES cells were derived. Subnuclear structures including nucleoli, interchromatin granule clusters, and Cajal bodies were observed in the nuclear interior. The architectural organization of human ES cell nuclei has important implications for cell structure-gene expression relationships and for the maintenance of pluripotency. J. Cell. Biochem. 118: 764-774, 2017. © 2016 Wiley Periodicals, Inc.


Assuntos
Células-Tronco Embrionárias Humanas/ultraestrutura , Linhagem Celular , Nucléolo Celular/ultraestrutura , Núcleo Celular/ultraestrutura , Estruturas do Núcleo Celular/ultraestrutura , Cromatina/ultraestrutura , Células-Tronco Embrionárias Humanas/metabolismo , Humanos , Microscopia Eletrônica , Microscopia de Fluorescência , Poro Nuclear/ultraestrutura
6.
J Contemp Dent Pract ; 18(10): 859-866, 2017 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-28989121

RESUMO

AIM: This study evaluated the efficacy of self-etching adhesive systems associated or not associated with the neodymium-doped yttrium aluminum garnet (Nd:YAG) laser on the protection against enamel erosive/abrasive wear. MATERIALS AND METHODS: Bovine enamel specimens were demineralized with 0.3% citric acid (5 minutes). The samples were randomly assigned to eight groups (n = 20): SB - Single Bond Universal (3M/ESPE); SB+L - Single Bond Universal + laser (80 mJ/10 Hz); FB - Futurabond U (Voco); FB+L -Futurabond U + laser; GEN - G-aenial bond (GC); GEN+L -G-aenial bond + laser; L - laser irradiation; and C - no treatment. The laser was applied before light curing. The samples were subjected to erosive/abrasive challenges (0.3% citric acid - 2 minutes and tooth brushing four times daily for 5 days). Enamel surface loss was recovered profilometrically by comparison of baseline and final profiles. The adhesive layer thickness, retention percentage of the protective layer, and microhardness of cured adhesive were measured. Data were analyzed using one-way analysis of variance and Tukey's test (5%). RESULTS: There were significant differences for all parameters (p = 0.0001). Mean values ± SD and results of the Tukey's test were: Surface wear: GEN - 4.88 (±1.09)a, L - 5.04 ± 0.99)a, FB - 5.32 (±0.93)ab, GEN + L - 5.46 (±1.27)abc, SB + L - 5.78 (±1.12)abc, FB + L - 6.23 (±1.25)bc, SB - 6.35 (±1.11)c, and C - 6.46 (±0.61)c; layer thickness: GEN - 15.2 (±8.63)c, FB - 5.06 (±1.96)a, GEN + L - 13.96 (±7.07)bc, SB + L - 4.24 (±2.68)a, FB + L - 9.03 (±13.02)abc, and SB - 7.49 (±2.80)ab; retention: GEN - 68.89 (±20.62)c, FB - 54.53 (±24.80)abc, GEN + L - 59.90 (±19.79)abc, SB + L - 63.37 (±19.30)bc, FB + L - 42.23 (±17.68) a, and SB - 47.78 (±18.29)ab; microhardness: GEN - 9.27 (±1.75)c; FB - 6.99 (±0.89)b; GEN + L - 6.22 (±0.87)ab; SB + L - 15.48 (±2.51)d; FB + L - 10.67 (±1.58)c; SB - 5.00 (±1.60)a. CONCLUSION: The application of Futurabond U and G-aenial bond on enamel surface, as well as the Nd:YAG laser irradiation alone, was able to reduce the enamel wear. The use of laser after the adhesive systems did not improve their efficacy. CLINICAL SIGNIFICANCE: Erosive/abrasive wear is a prevalent condition in clinical practice affecting many patients. The association of adhesive systems and Nd:YAG laser is of considerable clinical interest because it assesses new treatments to reduce the erosive/abrasive wear that would help dentists in clinical treatment decisions to reduce enamel wear and achieve a successful treatment.


Assuntos
Cimentos Dentários/uso terapêutico , Esmalte Dentário/lesões , Abrasão Dentária/prevenção & controle , Desgaste dos Dentes/prevenção & controle , Animais , Bovinos , Lasers de Estado Sólido/uso terapêutico
7.
Clin Oral Investig ; 20(7): 1577-87, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26572529

RESUMO

AIM: Citric acid (CA) is a component in beverages responsible for dental erosion. The aim of this study was to examine the influence of CA with different pH, titratable acid and buffer capacity (ß), and the impact of the chelating effect of CA on development of enamel erosions. MATERIAL AND METHODS: In a superfusion model, hydroxy apatite (HAp) dissolution of bovine enamel was measured in four experiments (EXP 1-4) with 27 experimental groups (n = 8 per group). The samples were superfused with different CA variations and respective controls. EXP-1: Dilution series of HCl (pH 2.15-3.02). EXP-2: Dilution series of natural CA (56-1.75 mmol l(-1); pH 2.15-3.02). EXP-3: CA solutions (56 and 14 mmol l(-1), ß: 39.7 and 10.2 mmol l(-1) pH(-1), respectively) with different titratable acidity at equal pH values. EXP-4: CA concentrations (56-1.75 mmol l(-1)) neutralized to pH 7. RESULTS: CA led to higher HAp-dissolution than HCl. With higher pH, the difference in HAp-dissolution rate between the two acids became increasingly smaller. At equal pH, HAp-dissolution was higher for the CA with the higher amount of titratable acid. However, no clear correlation between erosion and titratable acid or ß could be found. Only minimal amounts of HAp were dissolved by neutralized CA compared to CA with natural pH. CONCLUSION: Under the chosen conditions chelating effects of CA do not have a relevant influence of HAp-dissolution of enamel. Moreover, amount of HAp-dissolution by CA is not attributed to a single factor alone. The interplay between the different parameters of CA seems to be responsible for its erosive potential. CLINICAL RELEVANCE: The erosive potential of solutions containing citric acid with unknown concentrations could not be predicted using a single parameter alone, and should at best determined in experimental set-ups.


Assuntos
Bebidas , Ácido Cítrico/farmacologia , Esmalte Dentário/efeitos dos fármacos , Erosão Dentária/induzido quimicamente , Animais , Bovinos , Concentração de Íons de Hidrogênio , Técnicas In Vitro
8.
BMC Oral Health ; 15: 91, 2015 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-26243234

RESUMO

BACKGROUND: The purpose of this in-vitro study was to investigate the potential of biofilm removal in interproximal tooth regions using intervallic cleaning with an oral irrigator or a sonic toothbrush. METHODS: Three-species biofilms (Streptococcus mutans (OMZ 918), Streptococcus oralis SK 248 (OMZ 60), Actinomyces naeslundii (OMZ 745)) were grown on hydroxyapatite discs for 3 days in culture media. Every 24 h, specimens were incubated for 15 min in resazurin solution (i.e., culture medium and 10 % v/v alamarBlue®) to measure the metabolic activity with a fluorescence spectrophotometer in relative fluorescence units (rfu) at baseline. Then, specimens were fixed in interproximal holding devices and underwent treatment with an oral irrigator (WF; Waterpik® Sensonic WP-100E), an active sonic toothbrush (WPa), or an inactive sonic toothbrush (WPi; Waterpik® Sensonic SR-3000E) for 10 s (n = 18/group). Untreated biofilms served as controls (CO). After treatment, bacterial activity was re-measured, and specimens were re-grown in fresh medium for 24 h until next cleaning procedure. Altogether, cleaning was repeated in intervals of three treatment days (d1, d2, d3). After d3, SEM images were taken (n = 8) and CFU was measured (n = 3). Metabolic activity was analyzed for each disc separately, rfu values were averaged for d1 to compare initial biofilm stability, and ratios of baseline and post-treatment values were compared. Results were analyzed using ANOVA with the post-hoc Scheffé test, or Kruskal-Wallis with post-hoc Mann-Whitney test. RESULTS: Median baseline rfu-values of d1 resulted in 7821.8 rfu (interquartile range = 5114.5). Highest reduction in metabolic activity was recorded significantly for the oral irrigator used for 10 s (residual activity per day d1: WF 17.9 %, WPa 58.8 %, WPi 82.5 %, CO 89.6 %; d2: WF 36.8 %, WPa 85.2 %, WPi 82.5 %, CO 90.0 %; d3: WF 17.2.%, WPa 79.6 %, WPi 96.3 %, CO 116.3 %). SEM images of untreated specimens (CO) and specimens treated with the sonic toothbrush (WPa and WPi) showed huge amounts of biofilm, while oral irrigator-treated specimens (WF) revealed barely any bacteria. CFU data confirmed the graduations between the groups. CONCLUSIONS: Cleaning of interproximal regions achieved better success with an oral irrigator as compared to the use of a sonic toothbrush. (350/350 words).


Assuntos
Biofilmes , Dispositivos para o Cuidado Bucal Domiciliar , Irrigação Terapêutica/instrumentação , Dente/microbiologia , Escovação Dentária/instrumentação , Actinomyces/isolamento & purificação , Actinomyces/metabolismo , Carga Bacteriana , Técnicas Bacteriológicas , Durapatita/química , Desenho de Equipamento , Humanos , Indicadores e Reagentes , Teste de Materiais , Microscopia Eletrônica de Varredura , Oxazinas , Sonicação/instrumentação , Espectrometria de Fluorescência , Streptococcus mutans/isolamento & purificação , Streptococcus mutans/metabolismo , Streptococcus oralis/isolamento & purificação , Streptococcus oralis/metabolismo , Propriedades de Superfície , Fatores de Tempo , Xantenos
9.
BMC Gastroenterol ; 14: 20, 2014 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-24502393

RESUMO

BACKGROUND: Splenic abscesses in children are rare. In recent years aseptic abscesses have been recognized as a new disease entity, especially in adults. CASE PRESENTATION: We present a rare case of a 15 year old girl with aseptic abscesses, in whom antibiotic therapy comprising metronidazole and meropenem was partly beneficial in improving the patient's clinical condition and inflammatory parameters. Eventually corticosteroid therapy led to complete and long lasting resolution of symptoms. Further diagnostic work-up revealed autoimmune thyroiditis, but no signs of inflammatory bowel disease. CONCLUSION: Aseptic splenic abscesses should always prompt clinicians to initiate further diagnostics to determine a potential underlying condition and a regular follow-up. Anaerobic bacteria may play a role in the pathogenesis of the disease and besides corticosteroid treatment antibiotics covering anaerobes may be beneficial.


Assuntos
Abscesso Abdominal/tratamento farmacológico , Anti-Inflamatórios/uso terapêutico , Prednisona/uso terapêutico , Esplenopatias/tratamento farmacológico , Abscesso Abdominal/microbiologia , Adolescente , Antibacterianos/uso terapêutico , Feminino , Humanos , Esplenopatias/microbiologia
10.
Clin Oral Investig ; 18(3): 769-73, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23892498

RESUMO

OBJECTIVE: The objective of this in vitro study was to investigate the effect of viscosity-modified soft acidic drinks on enamel erosion. MATERIALS AND METHODS: A total of 108 bovine enamel samples (∅ = 3 mm) were embedded in acrylic resin and allocated into six groups (n = 18). Soft acidic drinks (orange juice, Coca-Cola, Sprite) were used both in their regular forms and at a kinetic viscositiy of 5 mm(2)/s, which was adjusted by adding hydroxypropyl cellulose. All solutions were pumped over the enamel surface from a reservoir with a drop rate of 3 ml/min. Each specimen was eroded for 10 min at 20 °C. Erosion of enamel surfaces was measured using profilometry. Data were analyzed using independent t tests and one-way ANOVAs (p < 0.05). RESULTS: Enamel loss was significantly higher for the regular (Coca-Cola, 5.60 ± 1.04 µm; Sprite, 5.49 ± 0.94 µm; orange juice, 1.35 ± 0.4 µm) than for the viscosity-modified drinks (Coca-Cola, 4.90 ± 0.34 µm; Sprite, 4.46 ± 0.39 µm; orange juice, 1.10 ± 0.22 µm). CONCLUSION: For both regular and viscosity-modified forms, Coca-Cola and Sprite caused higher enamel loss than orange juice. Increasing the viscosity of acidic soft drinks to 5 mm(2)/s reduced enamel erosion by 12.6-18.7 %. CLINICAL RELEVANCE: The erosive potential of soft acidic drinks is not only dependent on various chemical properties but also on the viscosity of the acidic solution and can be reduced by viscosity modification.


Assuntos
Bebidas , Esmalte Dentário , Viscosidade , Animais , Bovinos , Concentração de Íons de Hidrogênio , Técnicas In Vitro
11.
Chem Soc Rev ; 42(18): 7507-20, 2013 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-23364473

RESUMO

Technological and scientific challenges coupled with environmental considerations have prompted a search for simple and energy-efficient syntheses and processing routes of materials. This tutorial review provides an overview of recent research efforts in non-conventional reactions and syntheses of oxides induced by mechanical action. It starts with a brief account of the history of mechanochemistry. Ensuing discussions will review the progress in homogeneous and heterogeneous mechanochemical reactions in oxides of various structures. The review demonstrates that the event of mechanically induced reactions provides novel opportunities for the non-thermal manipulation of materials and for the tailoring of their properties.

12.
Hum Mov Sci ; 95: 103219, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38636393

RESUMO

PURPOSE: Neural and peripheral effects of induced muscle pain on explosive force production were investigated. METHODS: Nine participants performed two maximal, six explosive, and six electrical stimulations induced (twitches and octets) isometric knee extensions before and after (15 min of rest) receiving an intramuscular injection of hypertonic saline (pain inducer) or isotonic (placebo) infusions in two laboratory visits separated by 7 days. RESULTS: It was observed a reduction of peak torque production in maximal voluntary contraction in both conditions (9.3 and 3.3% for pain and placebo, respectively) and in the rate of torque development in placebo (7%). There was an increase in the rate of torque development for twitch and octets (10.5 and 15.8%, respectively) in the pain condition and peak torque for twitch (12%) in both conditions (as did the total rate of torque development for octets). CONCLUSION: Force production decreases and increases during voluntary and involuntary contractions, respectively, suggesting that acute pain impairs force production via central mechanisms.


Assuntos
Estimulação Elétrica , Contração Isométrica , Mialgia , Torque , Humanos , Masculino , Contração Isométrica/fisiologia , Mialgia/fisiopatologia , Adulto , Adulto Jovem , Solução Salina Hipertônica , Músculo Esquelético , Feminino , Eletromiografia
13.
Int J Sports Physiol Perform ; 19(3): 299-306, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38194958

RESUMO

PURPOSE: Fran is one of the most popular CrossFit benchmark workouts used to control CrossFitters' improvements. Detailed physiological characterization of Fran is needed for a more specific evaluation of CrossFitters' training performance improvements. The aim of the study was to analyze the oxygen uptake (V˙O2) kinetics and characterize the energy system contributions and the degree of postexercise fatigue of the unbroken Fran. METHODS: Twenty trained CrossFitters performed Fran at maximal exertion. V˙O2 and heart-rate kinetics were assessed at baseline and during and post-Fran. Blood lactate and glucose concentrations and muscular fatigue were measured at baseline and in the recovery period. RESULTS: A marked increase in V˙O2 kinetics was observed at the beginning of Fran, remaining elevated until the end (V˙O2peak: 49.2 [3.7] mL·kg-1·min-1, V˙O2 amplitude: 35.8 [5.2] mL·kg-1·min-1, time delay: 4.7 [2.5] s and time constant: 23.7 [11.1] s; mean [SD]). Aerobic, anaerobic lactic, and alactic pathways accounted for 62% (4%), 26% (4%), and 12% (2%) of energy contribution. Reduction in muscle function in jumping ability (jump height: 8% [6%], peak force: 6% [4%], and maximum velocity: 4% [2%]) and plank prone test (46% [20%]) was observed in the recovery period. CONCLUSIONS: The Fran unbroken workout is a high-intensity effort associated with an elevated metabolic response. This pattern of energy response highlights the primary contribution of aerobic energy metabolism, even during short and very intense CrossFit workouts, and that recovery can take >24 hours due to cumulative fatigue.


Assuntos
Fadiga , Consumo de Oxigênio , Humanos , Consumo de Oxigênio/fisiologia , Fadiga Muscular/fisiologia , Oxigênio , Músculos
14.
J Cell Physiol ; 228(1): 9-20, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22552993

RESUMO

Human embryonic stem cells (hESCs) and induced pluripotent stem cells proliferate rapidly and divide symmetrically producing equivalent progeny cells. In contrast, lineage committed cells acquire an extended symmetrical cell cycle. Self-renewal of tissue-specific stem cells is sustained by asymmetric cell division where one progeny cell remains a progenitor while the partner progeny cell exits the cell cycle and differentiates. There are three principal contexts for considering the operation and regulation of the pluripotent cell cycle: temporal, regulatory, and structural. The primary temporal context that the pluripotent self-renewal cell cycle of hESCs is a short G1 period without reducing periods of time allocated to S phase, G2, and mitosis. The rules that govern proliferation in hESCs remain to be comprehensively established. However, several lines of evidence suggest a key role for the naïve transcriptome of hESCs, which is competent to stringently regulate the embryonic stem cell (ESC) cell cycle. This supports the requirements of pluripotent cells to self-propagate while suppressing expression of genes that confer lineage commitment and/or tissue specificity. However, for the first time, we consider unique dimensions to the architectural organization and assembly of regulatory machinery for gene expression in nuclear microenviornments that define parameters of pluripotency. From both fundamental biological and clinical perspectives, understanding control of the abbreviated ESC cycle can provide options to coordinate control of proliferation versus differentiation. Wound healing, tissue engineering, and cell-based therapy to mitigate developmental aberrations illustrate applications that benefit from knowledge of the biology of the pluripotent cell cycle.


Assuntos
Ciclo Celular/fisiologia , Células-Tronco Embrionárias/citologia , Células-Tronco Embrionárias/fisiologia , Células-Tronco Pluripotentes/citologia , Células-Tronco Pluripotentes/fisiologia , Animais , Núcleo Celular/fisiologia , Regulação da Expressão Gênica/fisiologia , Genes myc/fisiologia , Histonas/genética , Histonas/metabolismo , Humanos , MicroRNAs
15.
Bioorg Med Chem Lett ; 23(23): 6310-2, 2013 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-24125880

RESUMO

A new series of 5-(1-aryl-3-methyl-1H-pyrazol-4-yl)-1H-tetrazole derivatives (4a-m) and their precursor 1-aryl-3-methyl-1H-pyrazole-4-carbonitriles (3a-m) were synthesized and evaluated as antileishmanials against Leishmania braziliensis and Leishmania amazonensis promastigotes in vitro. In parallel, the cytotoxicity of these compounds was evaluated on the RAW 264.7 cell line. The results showed that among the assayed compounds the substituted 3-chlorophenyl (4a) (IC50/24h=15±0.14 µM) and 3,4-dichlorophenyl tetrazoles (4d) (IC50/24h=26±0.09 µM) were the most potent against L. braziliensis promastigotes, as compared the reference drug pentamidine, which presented IC50=13±0.04 µM. In addition, 4a and 4d derivatives were less cytotoxic than pentamidine. However, these tetrazole derivatives (4) and pyrazole-4-carbonitriles precursors (3) differ against each of the tested species and were more effective against L.braziliensis than on L. amazonensis.


Assuntos
Leishmania/efeitos dos fármacos , Nitrilas/química , Pirazóis/química , Tetrazóis/síntese química , Tetrazóis/farmacologia , Animais , Antiprotozoários , Linhagem Celular , Relação Dose-Resposta a Droga , Camundongos , Estereoisomerismo , Relação Estrutura-Atividade , Tetrazóis/química
16.
Ecotoxicol Environ Saf ; 94: 172-8, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23706600

RESUMO

Jatropha curcas seeds are a promising feedstock for biodiesel production. However, Jatropha seed oil and other plant parts are toxic due to the presence of phorbol esters (PEs). The ever-increasing cultivation of toxic genotype of J. curcas runs the risk of increased human exposure to Jatropha products. In the present study, effects of J. curcas oil (from both toxic and nontoxic genotypes), purified PEs-rich extract and purified PEs (factors C1, C2, C(3mixture), (C4+C5)) on reconstituted human epithelium (RHE) and human corneal epithelium (HCE) were evaluated in vitro. The PEs were purified from toxic Jatropha oil. In both RHE and HCE, the topical application of PEs containing samples produced severe cellular alterations such as marked oedema, presence of less viable cell layers, necrosis and/or partial tissue disintegration in epithelium and increased inflammatory response (interleukin-1α and prostaglandin E2). When compared to toxic oil, histological alterations and inflammatory response were less evident (P<0.05) in nontoxic oil indicating the severity of toxicity was due to PEs. Conclusively, topical applications of Jatropha PEs are toxic towards RHE and HCE models, which represents dermal and occular toxicity respectively. Data obtained from this study would aid in the development of safety procedures for Jatropha biodiesel industries. It is advised to use protective gloves and glasses when handling PEs containing Jatropha products.


Assuntos
Biocombustíveis , Olho/efeitos dos fármacos , Substâncias Perigosas/toxicidade , Jatropha/química , Ésteres de Forbol/toxicidade , Extratos Vegetais/toxicidade , Pele/efeitos dos fármacos , Linhagem Celular , Dinoprostona/metabolismo , Humanos , Interleucina-1alfa/metabolismo , Medição de Risco , Testes de Toxicidade
17.
J Sci Food Agric ; 93(7): 1706-10, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23180465

RESUMO

BACKGROUND: Jatropha cordata and Jatropha cardiophylla are native to northwestern Mexico and are adapted to arid and semi-arid conditions (<500 mm of precipitation and temperatures from 8 to 45 °C). The aim of this study was to evaluate the chemical composition of J. cordata and J. cardiophylla kernels and oils as well as antinutrients in the defatted kernel meals of these species. RESULTS: Kernels of J. cordata and J. cardiophylla seeds analysed in this study were rich in crude protein (283 and 289 g kg(-1) respectively) and lipid (517 and 537 g kg(-1) respectively). The main fatty acids in J. cordata and J. cardiophylla oils were linoleic and oleic acids. High levels of trypsin inhibitor and phytates and low levels of saponins were present in the meals. The phorbol ester contents in J. cordata and J. cardiophylla kernel meals were 2.73 and 1.46 mg g(-1) respectively. CONCLUSION: For both J. cordata and J. cardiophylla it could be inferred that (a) the oil and kernel meal were toxic and the kernel meal could be used as livestock feed only after detoxification, (b) the oil could be used for non-alimentary purposes, i.e. biodiesel production, and (c) the seed or oil could be used for isolating various bioactive compounds for pharmaceutical and agricultural applications.


Assuntos
Ração Animal , Ácidos Graxos/análise , Indústrias , Jatropha/química , Óleos de Plantas/química , Proteínas de Plantas/análise , Sementes/química , Agricultura , Animais , Biocombustíveis , Indústria Farmacêutica , Ácido Linoleico/análise , Ácido Oleico/análise , Ésteres de Forbol/análise , Ácido Fítico/análise , Saponinas/análise , Especificidade da Espécie , Inibidores da Tripsina/análise
18.
Biomedicines ; 11(7)2023 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-37509681

RESUMO

Low back pain is one of the main causes of motor disabilities and psychological stress, with the painful process encompassing sensory and affective components. Noxious stimuli originate on the periphery; however, the stimuli are recombined in the brain and therefore processed differently due to the emotional environment. To better understand this process, our objective was to develop a mathematical representation of the International Association for the Study of Pain (IASP) model of pain, covering the multidimensional representation of this phenomenon. Data from the Oswestry disability index; the short form of the depression, anxiety, and stress scale; and pain catastrophizing daily questionnaires were collected through online completion, available from 8 June 2022, to 8 April 2023 (1021 cases). Using the information collected, an artificial neural network structure was trained (based on anomaly detection methods) to identify the patterns that emerge from the relationship between the variables. The developed model proved to be robust and able to show the patterns and the relationship between the variables, and it allowed for differentiating the groups with altered patterns in the context of low back pain. The distinct groups all behave according to the main finding that psychological and pain events are directly associated. We conclude that our proposal is effective as it is able to test and confirm the definition of the IASP for the study of pain. Here we show that the fiscal and mental dimensions of pain are directly associated, meaning that mental illness can be an enhancer of pain episodes and functionality.

19.
Crit Rev Food Sci Nutr ; 52(10): 899-935, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22747080

RESUMO

Nonstarch polysaccharides (NSPs) occur naturally in many foods. The physiochemical and biological properties of these compounds correspond to dietary fiber. Nonstarch polysaccharides show various physiological effects in the small and large intestine and therefore have important health implications for humans. The remarkable properties of dietary NSPs are water dispersibility, viscosity effect, bulk, and fermentibility into short chain fatty acids (SCFAs). These features may lead to diminished risk of serious diet related diseases which are major problems in Western countries and are emerging in developing countries with greater affluence. These conditions include coronary heart disease, colo-rectal cancer, inflammatory bowel disease, breast cancer, tumor formation, mineral related abnormalities, and disordered laxation. Insoluble NSPs (cellulose and hemicellulose) are effective laxatives whereas soluble NSPs (especially mixed-link ß-glucans) lower plasma cholesterol levels and help to normalize blood glucose and insulin levels, making these kinds of polysaccharides a part of dietary plans to treat cardiovascular diseases and Type 2 diabetes. Moreover, a major proportion of dietary NSPs escapes the small intestine nearly intact, and is fermented into SCFAs by commensal microflora present in the colon and cecum and promotes normal laxation. Short chain fatty acids have a number of health promoting effects and are particularly effective in promoting large bowel function. Certain NSPs through their fermented products may promote the growth of specific beneficial colonic bacteria which offer a prebiotic effect. Various modes of action of NSPs as therapeutic agent have been proposed in the present review. In addition, NSPs based films and coatings for packaging and wrapping are of commercial interest because they are compatible with several types of food products. However, much of the physiological and nutritional impact of NSPs and the mechanism involved is not fully understood and even the recommendation on the dose of different dietary NSPs intake among different age groups needs to be studied.


Assuntos
Fibras na Dieta/administração & dosagem , Polissacarídeos/administração & dosagem , Amido/administração & dosagem , beta-Glucanas/administração & dosagem , Glicemia/análise , Doenças Cardiovasculares/fisiopatologia , Doenças Cardiovasculares/prevenção & controle , Fenômenos Químicos , Colesterol/sangue , Colo/metabolismo , Colo/microbiologia , Diabetes Mellitus Tipo 2/fisiopatologia , Diabetes Mellitus Tipo 2/prevenção & controle , Dieta , Ácidos Graxos Voláteis/metabolismo , Fermentação , Humanos , Insulina/sangue , Intestino Grosso/metabolismo , Intestino Grosso/microbiologia , Intestino Delgado/metabolismo , Intestino Delgado/microbiologia , Neoplasias/fisiopatologia , Neoplasias/prevenção & controle , Estado Nutricional , Polissacarídeos/metabolismo , Prebióticos
20.
Phys Chem Chem Phys ; 14(37): 12930-7, 2012 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-22899249

RESUMO

The oxidation kinetics of nitrogen doped, oxygen deficient titanium dioxide thin films has been studied in atmospheres of pure oxygen or nitrogen at 500 °C, 550 °C, and 600 °C, respectively, by means of in situ optical spectroscopy. The thin films show high electronic absorbance in the visible and NIR region, accompanied by a red shift of the absorption edge of about 0.4 eV, e.g., from about 2.9 to 2.5 eV at 600 °C. The time dependent decrease of absorbance due to oxidation is found to follow a parabolic rate law. An activation energy of about 1.96 eV can be obtained from the temperature dependence of the parabolic oxidation rate constant. In the framework of a microscopic oxidation model, this energy barrier is attributed to the diffusion of titanium interstitials in the re-oxidized part of the thin films as a rate-determining process. In addition, an attempt is made to evaluate the kinetics of nitrogen release from the time dependent blue shift of the absorption edge during re-oxidation.

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