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1.
Chemosphere ; 326: 138447, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36940833

RESUMO

Microalgae biomass is a versatile feedstock with a variable composition that can be submitted to several conversion routes. Considering the increasing energy demand and the context of third-generation biofuels, algae can fulfill the increasing global demand for energy with the additional benefit of environmental impact mitigation. While biodiesel and biogas are widely consolidated and reviewed, emerging algal-based biofuels such as biohydrogen, biokerosene, and biomethane are cutting-edge technologies in earlier stages of development. In this context, the present study covers their theoretical and practical conversion technologies, environmental hotspots, and cost-effectiveness. Scaling-up considerations are also addressed, mainly through Life Cycle Assessment results and interpretation. Discussions on the current literature for each biofuel directs researchers towards challenges such as optimized pretreatment methods for biohydrogen and optimized catalyst for biokerosene, besides encouraging pilot and industrial scale studies for all biofuels. While presenting studies for larger scales, biomethane still needs continuous operation results to consolidate the technology further. Additionally, environmental improvements on all three routes are discussed in light of life-cycle models, highlighting the ample research opportunities on wastewater-grown microalgae biomass.


Assuntos
Biocombustíveis , Microalgas , Águas Residuárias , Biomassa , Tecnologia , Plantas
2.
Sci Rep ; 13(1): 92, 2023 01 26.
Artigo em Inglês | MEDLINE | ID: mdl-36702848

RESUMO

Intraspecific social interactions in domestic cats are often categorised as affiliative or agonistic. However, public or professional assessment of encounters can have difficulty distinguishing rough-and-tumble play from true agonism. One possible issue is the potential occurrence of elements of both, play and agonism, within inter-cat play, for example when one cat wants to terminate a bout of play but the other seeks to continue the interaction, which subsequently may provoke more overt agonistic behaviour. To test this hypothesis, we conducted behavioural observations of 105 unique dyadic interactions of domestic cats (N = 210) captured on videos collected from owners and YouTube. We assessed cats for the frequency and duration of six behavioural elements. The dataset was reduced using PCA with a varimax rotation and factor scores were used to classify the population using hierarchical cluster analysis. To validate the identified clusters, the average scores of the constituent factors were compared and the data on interactions were labelled by four cat behaviour experts as "playful", "intermediate" or "agonistic". In addition, to evaluate properties of expert-labelled categories we used linear discriminant analysis followed by an ordinal regression. The results showed considerable convergent validity in factor distributions between clusters and expert-labelled groups: reciprocal wrestling was most closely associated with a group of playfully interacting cats, while vocalisation and chasing were associated with the agonistic group. The intermediate group, while having characteristics of both, was more closely related to the playful group than the agonistic group, with prolonged exchanges of interactive behaviours being a predominant feature. Thus, our findings support the suggestion of there being an intermediate category between mutual social play and agonism. This might escalate into a fully agonistic encounter, but does not necessarily reflect a break down in their social relationship but rather a short-term disagreement in social priorities.


Assuntos
Comportamento Agonístico , Relações Interpessoais , Animais , Gatos , Interação Social , Inquéritos e Questionários
3.
Mater Today Commun ; 34: 105192, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36570033

RESUMO

We carried out theoretical and experimental analyses of ZnO and ZnS nanoparticles as smart semiconductor materials in light-activated antimicrobial coating for application in masks. We used low-cost hydrothermally processable precursors to direct the growth of the coatings on cotton fabric. Both ZnO and ZnS coatings had high reactivities as disinfection agents in photocatalysis reactions for the degradation of a methylene blue dye solution. Also, these coatings showed excellent UV protection properties. For understanding at the molecular level, the broad-spectrum biological activities of the ZnO and ZnS coatings against Fusarium Oxysporum fungi, Escherichia coli bacteria, and severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) virus and their variants, were investigated computationally. Hexagonal Zn6O6 and Zn6S6 clusters were used as models for the simulations through excited- and ground-state calculations. The theoretical findings show that changes in the local chemical environment in these excited systems have a profound impact on their physical and chemical properties and thus, can provide a better understanding to engineer new functional materials in light-activated antimicrobial coatings for the mitigation of SARS-CoV-2 infection.

6.
Exp Gerontol ; 156: 111607, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34715304

RESUMO

The effects of aging on ROS production and DNA damage were assessed in hematopoietic stem cells (HSCs) from apolipoprotein E-deficient (ApoE-/-) mice (2-, 12- and 24-month-old), a traditional experimental model of atherogenic dyslipidemia. HSCs from aged ApoE-/- mice were associated with increased ROS levels, leading to loss quiescence, DNA damage, apoptosis and telomere shortening. The concurrence of lack of ApoE and aging result in exhaustion and senescence of HSCs accompanied by increased oxidative stress and inflammation. Therefore, our data open avenues to a better understanding of age-related changes and genetic factors, which may synergistically compromise the efficacy of aged HSC recovery and/or transplantation.


Assuntos
Células-Tronco Hematopoéticas , Estresse Oxidativo , Envelhecimento , Animais , Apolipoproteínas E/genética , Senescência Celular , Dano ao DNA , Camundongos , Camundongos Endogâmicos C57BL , Espécies Reativas de Oxigênio
9.
J Photochem Photobiol B ; 201: 111634, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31715551

RESUMO

Skin Flap is used in reconstructive plastic surgery. However, complications such as ischemia followed by local necrosis may occur, requiring a new surgical procedure. It is well known that photobiomodulation therapy (PBMT) is an effective technique for improving microcirculation and neoangiogenesis, which contributes positively to the blood supply in the pre and post surgical period. Thus, the objective of the present study was to investigate the effects of preemptive treatment with laser PBMT with different energies on the viability in skin flaps in rats. Sixty-three Wistar rats, male, were randomized into five groups: Control Group (CG) (n = 15): PBMT simulation; Preemptive group 1.1 J laser (GP1) (n = 15): preemptive laser PBMT with 1.1 J of energy per point; Preemptive group 4 J laser (GP4) (n = 15): preemptive PBMT with 4 J of energy per point; Laser group 11 J (G1) (n = 9): PBMT immediately after surgery with 1.1 J of energy per point; Laser group 4 J (G4) (n = 9): TFMB immediately after surgery with 4 J of energy per point. The CG, GP1 and GP4 groups started treatment 72 h prior to surgery and were subdivided into two experimental periods, one of them on the day of the flap and the other along with the other groups on the seventh postoperative day. Three days after the randomization, the animals underwent random skin flap surgery. PBMT was performed with a 660 nm laser at three points. In the first experimental period, a greater number of vessels were found, as well as mast cells in GP1 compared to the CG and greater expression of fibroblast growth factor and vascular endothelial growth factor in the GP1 and GP4 groups compared to the CG. In the second experimental period, GP1 presented a lower percentage of necrotic tissue, a higher number of vessels and a percentage of cells labeled with both VEGF and hypoxia indicible factor alpha (HIF-1α) compared to the CG, FGF in GP1, GP4 and G4 when compared to the CG. Thus, it was concluded that preemptive treatment with PBMT with the application of 1.1 J of energy per point is effective in improving the viability of the skin flap.


Assuntos
Lasers Semicondutores , Retalhos Cirúrgicos , Animais , Masculino , Ratos , Vasos Sanguíneos/patologia , Vasos Sanguíneos/efeitos da radiação , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Mastócitos/citologia , Mastócitos/metabolismo , Mastócitos/efeitos da radiação , Necrose , Distribuição Aleatória , Ratos Wistar , Retalhos Cirúrgicos/irrigação sanguínea , Retalhos Cirúrgicos/patologia , Fator A de Crescimento do Endotélio Vascular/metabolismo
10.
Lasers Med Sci ; 34(5): 1041-1047, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30565200

RESUMO

To identify the best low level laser photobiomodulation application site at the same irradiation time to increase the viability of the skin flap in rats. Eighteen male rats (Rattus norvegicus: var. Albinus, Rodentia Mammalia) were randomly distributed into three groups (n = 6). Group I (GI) was submitted to simulated laser photobiomodulation; group II (GII) was submitted to laser photobiomodulation at three points in the flap cranial base, and group III (GIII) was submitted to laser photobiomodulation at 12 points distributed along the flap. All groups were irradiated with an Indium, Galium, Aluminum, and Phosphorus diode laser (InGaAlP), 660 nm, with 50 mW power, irradiated for a total time of 240 s in continuous emission mode. The treatment started immediately after performing the cranial base random skin flap (10 × 4 cm2 dimension) and reapplied every 24 h, with a total of five applications. The animals were euthanized after the evaluation of the percentage of necrosis area, and the material was collected for histological analysis on the seventh postoperative day. GII animals presented a statistically significant decrease for the necrosis area when compared to the other groups, and a statistically significant increase in the quantification of collagen when compared to the control. We did not observe a statistical difference between the TGFß and FGF expression in the different groups evaluated. The application of laser photobiomodulation at three points of the flap cranial base was more effective than at 12 points regarding the reduction of necrosis area.


Assuntos
Terapia com Luz de Baixa Intensidade , Pele/efeitos da radiação , Retalhos Cirúrgicos , Sobrevivência de Tecidos/efeitos da radiação , Animais , Núcleo Celular/metabolismo , Núcleo Celular/efeitos da radiação , Colágeno/metabolismo , Fatores de Crescimento de Fibroblastos/metabolismo , Fibroblastos/metabolismo , Fibroblastos/efeitos da radiação , Lasers Semicondutores , Masculino , Necrose , Ratos Wistar , Fator de Crescimento Transformador beta/metabolismo
11.
Arq. bras. med. vet. zootec. (Online) ; 70(3): 897-904, maio-jun. 2018. tab
Artigo em Português | LILACS, VETINDEX | ID: biblio-911667

RESUMO

Objetivou-se avaliar o efeito dos fenos de andropogon, buffel e massai em diferentes intervalos de cortes sob consumo, comportamento ingestivo e o desempenho de ovinos. O delineamento experimental foi inteiramente ao acaso. Os tratamentos foram arranjados em fatorial 3x4 (andropogon, buffel e massai x intervalos entre corte de 21, 35, 49 e 63 dias). A interação entre as gramíneas e os intervalos não foi significativa para nenhuma das variáveis estudadas. Os maiores consumos de matéria seca, proteína bruta, fibra em detergente neutro e lignina ocorreram com uso do feno de massai, 3,62; 0,48; 2,03 e 0,22% do peso vivo, respectivamente. Aos 63 dias de intervalo, foram observados os maiores consumos de lignina e os menores de proteína bruta, 0,20 e 0,42%, respectivamente. O menor ganho médio diário (121,1g/dia) e o menor peso final (17,6kg) foram dos animais alimentados com buffel. Não houve diferença para o tempo de alimentação e o ócio, com tempo médio despendido de 4,5 e 11,7h/dia, respectivamente. Os fenos de massai e andropogon promovem maior consumo de matéria seca e maior desempenho de ovinos em confinamento, enquanto o intervalo entre corte até 63 dias não modifica essas respostas.(AU)


The objective of this study was to evaluate the effect of Andropogon, Buffel and Massai on different intervals cuts of intake, ingestion behavior and sheep performance. The experimental design was completely randomized. The treatments were arranged in 3x4 factorial (Andropogon, Buffel and Massai x cut intervals of 21, 35, 49 and 63 days). The interaction between the grasses and the intervals was not significant for any of the studied variables. The highest intakes of dry matter, crude protein, neutral detergent fiber, acid detergent fiber and lignin were for Massai hay, 3.62; 0.48; 2.03 and 0.22% of the live weight, respectively. At 63 days interval, the highest consumption of lignin and lowest crude protein, 0.20 and 0.42%, respectively, were observed. The lowest daily gain (121.1g/day) and final weight gain (17,6kg) were of Buffel fed animals. There was no difference in feeding time and time, with mean time removed from 4.5 and 11.7h day-1, respectively. Hays of Massai and Andropogon promote greater dry matter intake and performance of sheep in confinement, while the cut intervals up to 63 days does not modify these responses.(AU)


Assuntos
Animais , Alimentos/análise , Poaceae , Ovinos/crescimento & desenvolvimento , Comportamento Alimentar
12.
Drug Resist Updat ; 31: 1-14, 2017 03.
Artigo em Inglês | MEDLINE | ID: mdl-28867240

RESUMO

Staphylococcus aureus is a major cause of bacterial infection in humans, and has been notoriously able to acquire resistance to a variety of antibiotics. An example is methicillin-resistant S. aureus (MRSA), which despite having been initially associated with clinical settings, now is one of the key causative agents of community-acquired infections. Antibiotic resistance in S. aureus involves mechanisms ranging from drug efflux to increased expression or mutation of target proteins, and this has required innovative approaches to develop novel treatment methodologies. This review provides an overview of the major mechanisms of antibiotic resistance developed by S. aureus, and describes the emerging alternatives being sought to circumvent infection and proliferation, including new generations of classic antibiotics, synergistic approaches, antibodies, and targeting of virulence factors.


Assuntos
Antibacterianos/uso terapêutico , Farmacorresistência Bacteriana Múltipla , Infecções Estafilocócicas/tratamento farmacológico , Staphylococcus aureus/efeitos dos fármacos , Animais , Antibacterianos/administração & dosagem , Parede Celular/efeitos dos fármacos , Infecções Comunitárias Adquiridas , Descoberta de Drogas , Farmacorresistência Bacteriana Múltipla/efeitos dos fármacos , Farmacorresistência Bacteriana Múltipla/genética , Humanos , Mutação , Proteínas de Ligação às Penicilinas/genética , Proteínas de Ligação às Penicilinas/metabolismo , Infecções Estafilocócicas/microbiologia , Staphylococcus aureus/genética
13.
Braz J Med Biol Res ; 50(9): e6048, 2017 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-28793050

RESUMO

Uric acid (UA) levels are increased in patients with kidney dysfunction. We analyzed the association between asymptomatic hyperuricemia and new-onset chronic kidney disease (CKD). A retrospective cohort study was designed to collect data from employees of an energy generation and distribution company in the city of Rio de Janeiro, Brazil, who had undergone the company's annual medical checkup from 2008 to 2014. People with ≤2 years of follow-up, with baseline estimated glomerular filtration rate (eGFR) <60 mL·min-1·(1.73 m2)-1 or with incomplete data were excluded. The endpoint was defined as eGFR <60 mL·min-1·(1.73 m2)-1 estimated through the chronic kidney disease epidemiology collaboration equation (CKD-EPI). The study included 1094 participants. The mean follow-up period was 5.05±1.05 years and 44 participants exhibited new-onset CKD. The prevalence of hyperuricemia was 4.2%. There was a significant inverse correlation between baseline serum levels of UA and baseline eGFR (R=-0.21, P<0.001). Female gender (OR=4.00; 95%CI=1.92-8.29, P<0.001) and age (OR=1.06; 95%CI=1.02-1.11, P=0.004) but not UA levels (OR=1.12; 95%CI=0.83-1.50; P=0.465) were associated with new-onset CKD. Diabetes mellitus and body mass index were independent factors for fast progression (OR=2.17; 95%CI=1.24-3.80, P=0.007 and OR=1.04; 95%CI=1.01-1.07; P=0.020). These results did not support UA as an independent predictor for CKD progression in the studied population.


Assuntos
Hiperuricemia/complicações , Insuficiência Renal Crônica/etiologia , Ácido Úrico/sangue , Brasil , Progressão da Doença , Feminino , Taxa de Filtração Glomerular , Humanos , Hiperuricemia/sangue , Hiperuricemia/diagnóstico , Masculino , Pessoa de Meia-Idade , Insuficiência Renal Crônica/sangue , Insuficiência Renal Crônica/diagnóstico , Estudos Retrospectivos , Fatores de Risco
14.
J Photochem Photobiol B ; 173: 258-265, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28603084

RESUMO

The main purpose of the present work was to evaluate if low laser level therapy (LLLT) can improve the effects of Biosilicate®/PLGA (BS/PLGA) composites on cell viability and bone consolidation using a tibial defects of rats. The composites were characterized by scanning electron microscope (SEM) and reflection Fourier transform infrared spectrometer (FTIR). For the in vitro study, fibroblast and osteoblast cells were seeded in the extract of the composites irradiated or not with LLLT (Ga-Al-As, 808nm, 10J/cm2) to assess cell viability after 24, 48 and 72h. For the in vivo study, 80 Wistar rats with tibial bone defects were distributed into 4 groups (BS; BS+LLLT; BS/PLGA and BS/PLGA+LLLT) and euthanized after 2 and 6weeks. Laser irradiation Ga-Al-As (808nm, 30J/cm2) in the rats was performed 3 times a week. The SEM and FTIR results revealed that PLGA were successfully inserted into BS and the microparticles degraded over time. The in vitro findings demonstrated higher fibroblast viability in both BS/PLGA groups after 24h and higher osteoblast viability in BS/PLGA+LLLT in all periods. As a conclusion, animals treated with BS/PLGA+LLLT demonstrated an improved material degradation and an increased amount of granulation tissue and newly formed bone.


Assuntos
Materiais Biocompatíveis/química , Materiais Biocompatíveis/farmacologia , Ácido Láctico/química , Terapia com Luz de Baixa Intensidade , Osteogênese/efeitos dos fármacos , Osteogênese/efeitos da radiação , Ácido Poliglicólico/química , Silicatos/química , Animais , Fenômenos Biomecânicos , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos da radiação , Masculino , Copolímero de Ácido Poliláctico e Ácido Poliglicólico , Ratos , Ratos Wistar
15.
Sci Rep ; 7: 43692, 2017 03 07.
Artigo em Inglês | MEDLINE | ID: mdl-28266547

RESUMO

Myosin Va (MyoVa) is an actin-based molecular motor abundantly found at the centrosome. However, the role of MyoVa at this organelle has been elusive due to the lack of evidence on interacting partners or functional data. Herein, we combined yeast two-hybrid screen, biochemical studies and cellular assays to demonstrate that MyoVa interacts with RPGRIP1L, a cilia-centrosomal protein that controls ciliary signaling and positioning. MyoVa binds to the C2 domains of RPGRIP1L via residues located near or in the Rab11a-binding site, a conserved site in the globular tail domain (GTD) from class V myosins. According to proximity ligation assays, MyoVa and RPGRIP1L can interact near the cilium base in ciliated RPE cells. Furthermore, we showed that RPE cells expressing dominant-negative constructs of MyoVa are mostly unciliated, providing the first experimental evidence about a possible link between this molecular motor and cilia-related processes.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Cadeias Pesadas de Miosina/metabolismo , Miosina Tipo V/metabolismo , Proteínas Adaptadoras de Transdução de Sinal/química , Proteínas Adaptadoras de Transdução de Sinal/genética , Sequência de Aminoácidos , Sítios de Ligação , Centrossomo/metabolismo , Cílios/genética , Cílios/metabolismo , Sequência Conservada , Humanos , Modelos Moleculares , Cadeias Pesadas de Miosina/química , Cadeias Pesadas de Miosina/genética , Miosina Tipo V/química , Miosina Tipo V/genética , Ligação Proteica , Conformação Proteica , Domínios e Motivos de Interação entre Proteínas , Proteínas Recombinantes
16.
J Biomed Mater Res B Appl Biomater ; 105(5): 1063-1074, 2017 07.
Artigo em Inglês | MEDLINE | ID: mdl-26987304

RESUMO

The aims of this study were to characterize different BS/PLGA composites for their physicochemical and morphological characteristics and evaluate the in vitro and in vivo biological performance. The physicochemical and morphological modifications were analyzed by pH, mass loss, XRD, setting time, and SEM. For in vitro analysis, the osteoblast and fibroblast viability was evaluated. For in vivo evaluations, histopathology and immunohistochemistry were performed in a tibial defect in rats. After incubation, all composites presented lower values in pH and mass loss over time. Moreover, XRD and SEM analysis confirmed that the composites degraded over time. Additionally, pore formation was observed by SEM analysis after incubation mainly in BS/PLGA groups. BS/PLGA showed significantly increased in osteoblast viability 24 h. Moreover, BS/PLGA composites demonstrated an increase in fibroblast viability in all periods analyzed when compared to BS. In the in vivo study, after 2 and 6 weeks of implantation of biomaterials, histopathological findings revealed that the BS/PLGA composites degrades over time, mainly at periphery. Moreover, can be observed the presence of granulation tissue, bone formation, Runx-2, and RANKL immunoexpression in all groups. In conclusion, BS/PLGA composites present appropriate physicochemical characteristics, stimulate the cellular viability, and enhance the bone repair in vivo. © 2016 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 105B: 1063-1074, 2017.


Assuntos
Ácido Láctico , Teste de Materiais , Osteoblastos/metabolismo , Ácido Poliglicólico , Silicatos , Tíbia/metabolismo , Fraturas da Tíbia/terapia , Animais , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Fibroblastos/citologia , Fibroblastos/patologia , Concentração de Íons de Hidrogênio , Ácido Láctico/química , Ácido Láctico/farmacologia , Camundongos , Osteoblastos/patologia , Osteogênese/efeitos dos fármacos , Ácido Poliglicólico/química , Ácido Poliglicólico/farmacologia , Copolímero de Ácido Poliláctico e Ácido Poliglicólico , Ratos , Silicatos/química , Silicatos/farmacologia , Tíbia/patologia , Fraturas da Tíbia/metabolismo , Fraturas da Tíbia/patologia
17.
Biochim Biophys Acta ; 1863(6 Pt A): 1119-33, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26947915

RESUMO

The skin possesses a photosensitive system comprised of opsins whose function is not fully understood, and clock genes which exert an important regulatory role in skin biology. Here, we evaluated the presence of opsins in normal (Melan-a cells) and malignant (B16-F10 cells) murine melanocytes. Both cell lines express Opn2, Opn4--for the first time reported in these cell types--as well as S-opsin. OPN4 protein was found in a small area capping the cell nuclei of B16-F10 cells kept in constant dark (DD); twenty-four hours after the white light pulse (WLP), OPN4 was found in the cell membrane. Despite the fact that B16-F10 cells expressed less Opn2 and Opn4 than Melan-a cells, our data indicate that the malignant melanocytes exhibited increased photoresponsiveness. The clock gene machinery is also severely downregulated in B16-F10 cells as compared to Melan-a cells. Per1, Per2, and Bmal1 expression increased in B16-F10 cells in response to WLP. Although no response in clock gene expression to WLP was observed in Melan-a cells, gene correlational data suggest a minor effect of WLP. In contrast to opsins and clock genes, melanogenesis is significantly upregulated in malignant melanocytes in comparison to Melan-a cells. Tyrosinase expression increased after WLP only in B16-F10 cells; however no increase in melanin content after WLP was seen in either cell line. Our findings may prove useful in the treatment and the development of new pharmacological approaches of depigmentation diseases and skin cancer.


Assuntos
Expressão Gênica/efeitos da radiação , Luz , Melaninas/biossíntese , Melanócitos/efeitos da radiação , Animais , Proteínas CLOCK/genética , Proteínas CLOCK/metabolismo , Linhagem Celular , Linhagem Celular Tumoral , Imuno-Histoquímica , Melanócitos/metabolismo , Melanoma/genética , Melanoma/metabolismo , Melanoma/patologia , Camundongos , Microscopia de Fluorescência , Monofenol Mono-Oxigenase/genética , Monofenol Mono-Oxigenase/metabolismo , Opsinas/genética , Opsinas/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Fatores de Tempo
18.
Cell Tissue Res ; 363(2): 579-88, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26077926

RESUMO

INSL3 (insulin-like peptide 3) is a relaxin peptide family member expressed by Leydig cells in the vertebrate testis. In mammals, INSL3 mediates testicular descent during embryogenesis but information on its function in adults is limited. In fish, the testes remain in the body cavity, although the insl3 gene is still expressed, suggesting yet undiscovered, evolutionary older functions. Anti-Müllerian hormone (Amh), in addition to inhibiting spermatogonial differentiation and androgen release, inhibits the Fsh (follicle-stimulating hormone)-induced increase in insl3 transcript levels in zebrafish testis. Therefore, the two growth factors might have antagonistic effects. We examine human INSL3 (hINSL3) effects on zebrafish germ cell proliferation/differentiation and androgen release by using a testis tissue culture system. hINSL3 increases the proliferation of type A undifferentiated (Aund) but not of type A differentiating (Adiff) spermatogonia, while reducing the proliferation of Sertoli cells associated with proliferating Aund. Since the area occupied by Aund decreases and that of Adiff increases, we conclude that hINSL3 recruits Aund into differentiation; this is supported by the hINSL3-induced down-regulation of nanos2 transcript levels, a marker of single Aund spermatogonia in zebrafish and other vertebrates. Pulse-chase experiments with a mitosis marker also indicate that hINSL3 promotes spermatogonial differentiation. However, hINSL3 does not modulate basal or Fsh-stimulated androgen release or growth factor transcript levels, including those of amh. Thus, hINSL3 seems to recruit Aund spermatogonia into differentiation, potentially mediating an Fsh effect on spermatogenesis.


Assuntos
Envelhecimento/fisiologia , Diferenciação Celular/efeitos dos fármacos , Insulina/farmacologia , Proteínas/farmacologia , Espermatogônias/citologia , Peixe-Zebra/crescimento & desenvolvimento , Envelhecimento/efeitos dos fármacos , Androgênios/metabolismo , Animais , Bromodesoxiuridina/metabolismo , Proliferação de Células/efeitos dos fármacos , Forma Celular/efeitos dos fármacos , Hormônio Foliculoestimulante/metabolismo , Regulação da Expressão Gênica no Desenvolvimento/efeitos dos fármacos , Humanos , Masculino , Transporte Proteico/efeitos dos fármacos , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Células de Sertoli/citologia , Células de Sertoli/efeitos dos fármacos , Células de Sertoli/metabolismo , Testículo , Peixe-Zebra/genética
19.
Osteoarthritis Cartilage ; 24(1): 169-77, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26254236

RESUMO

OBJECTIVE: The aim of this study was to evaluate the effects of an aerobic exercise training and low-level laser therapy (LLLT) (associated or not) on degenerative modifications and inflammatory mediators on the articular cartilage using an experimental model of knee OA. MATERIAL AND METHODS: Fifty male Wistar rats were randomly divided into five groups: control group (CG); knee OA control group (OAC); OA plus exercise training group (OAT); OA plus LLLT group (OAL); OA plus exercise training associated with LLLT group (OATL). The exercise training (treadmill; 16 m/min; 50 min/day) and the laser irradiation (two points-medial and lateral side of the left joint; 24 sessions) started 4 weeks after the surgery, 3 days/week for 8 weeks. RESULTS: The results showed that all treated groups showed (irradiated or not) a better pattern of tissue organization, with less fibrillation and irregularities along the articular surface and chondrocytes organization, a lower degenerative process measured by OARSI score and higher thickness values. Additionally, all treated group showed a reduced expression in IL-1ß, caspase-3 and MMP-13 compared to OAC. Moreover, a lower caspase-3 expression was observed in OATL compared to OAL and OAT. CONCLUSION: These results suggest that exercise training and LLLT were effective in preventing cartilage degeneration and modulating inflammatory process induced by knee OA.


Assuntos
Lesões do Ligamento Cruzado Anterior , Cartilagem Articular/patologia , Condrócitos/patologia , Terapia com Luz de Baixa Intensidade/métodos , Osteoartrite do Joelho/reabilitação , Condicionamento Físico Animal/métodos , Joelho de Quadrúpedes/patologia , Animais , Cartilagem Articular/metabolismo , Caspase 3/metabolismo , Condrócitos/metabolismo , Modelos Animais de Doenças , Imuno-Histoquímica , Interleucina-1beta/metabolismo , Masculino , Metaloproteinase 13 da Matriz/metabolismo , Osteoartrite do Joelho/metabolismo , Osteoartrite do Joelho/patologia , Ratos , Ratos Wistar , Joelho de Quadrúpedes/metabolismo
20.
Neuroscience ; 279: 220-31, 2014 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-25194788

RESUMO

ß-Caryophyllene (BCP), a natural bicyclic sesquiterpene present in several essential oils, displays analgesic and anti-inflammatory properties in vitro and in vivo. Astrocytes are a major class of glial cells that regulate extracellular ion balance, repair and scarring processes in the CNS following neuroinflammatory conditions and traumatic injuries. This study sought to determine the protective effect of BCP against glutamate (Glu)-induced cytotoxicity in the C6 glioma cell line on neurochemical parameters as well as their biochemical mechanism. Glu increases intracellular reactive oxygen species (ROS) production and induces mitochondrial dysfunction as well as decreasing antioxidant defenses such as glutathione (GSH) and glutathione peroxidase activity. BCP prevented C6 cells from Glu-induced cytotoxicity by modulating the cellular antioxidant response, mainly by inhibiting ROS production and reestablishing the mitochondrial membrane potential (Δψm). Moreover, BCP per se induced the nuclear translocation of nuclear factor (erythroid-derived 2)-like 2 (Nrf2) which was reflected by improvement in the cellular GSH antioxidant system. Taken together, our results suggest that cytoprotective effects of BCP were mediated by the amelioration of cellular antioxidant responses via Nrf2 activation, which is, in part, dependent on cannabinoid receptor type 2 (CB2R) activation. This functional nonpsychoactive CB2R ligand, could represent an important molecule for protection of glial cells against oxidative stress induced by glutamate.


Assuntos
Astrócitos/efeitos dos fármacos , Ácido Glutâmico/toxicidade , Fator 2 Relacionado a NF-E2/metabolismo , Fármacos Neuroprotetores/farmacologia , Sesquiterpenos/farmacologia , Animais , Astrócitos/fisiologia , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/fisiologia , Relação Dose-Resposta a Droga , Glutationa/metabolismo , Glutationa Peroxidase/metabolismo , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Potencial da Membrana Mitocondrial/fisiologia , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/fisiologia , Sesquiterpenos Policíclicos , Ratos , Espécies Reativas de Oxigênio/metabolismo
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