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1.
Int J Mol Sci ; 23(20)2022 Oct 19.
Artigo em Inglês | MEDLINE | ID: mdl-36293403

RESUMO

Human papillomavirus type 16 (HPV-16) is a well-known etiological factor for cervical and oropharyngeal cancers. The E2 protein, the product of an early-transcribed gene in HPV-16, is postulated to cause the death of cancerous cells via p53-dependent and p53-independent pathways. The main aim of the present systematic review was to study the HPV 16-E2 protein as an apoptosis-inducer agent. A thorough search of MEDLINE/PubMed, Science Direct, Scopus, and EBSCOhost databases was conducted for relevant studies on HPV AND apoptosis OR cell death where HPV 16-E2 was involved. The search identified 967 publications. Eleven records dated from 1 January 1997 to 16 February 2022 were found to meet the inclusion criteria and were eligible for data extraction and inclusion. All studies concluded that HPV 16-E2 was able to induce cell death in transfected cells. E2 proteins from the high-risk HPV-16 were able to induce apoptosis through different apoptotic pathways depending on the location of the expressed gene. However, the mechanism was still unclear, and further studies are warranted.


Assuntos
Proteínas Oncogênicas Virais , Neoplasias Orofaríngeas , Infecções por Papillomavirus , Neoplasias do Colo do Útero , Humanos , Feminino , Proteínas Reguladoras de Apoptose/metabolismo , Proteína Supressora de Tumor p53/metabolismo , Proteínas Oncogênicas Virais/genética , Papillomavirus Humano 16/metabolismo , Apoptose/genética , Neoplasias do Colo do Útero/genética , Papillomaviridae/genética
2.
Artigo em Inglês | MEDLINE | ID: mdl-34071757

RESUMO

Molybdenum (Mo) microbial bioreduction is a phenomenon that is beginning to be recognized globally as a tool for the remediation of molybdenum toxicity. Molybdenum toxicity continues to be demonstrated in many animal models of spermatogenesis and oogenesis, particularly those of ruminants. The phenomenon has been reported for more than 100 years without a clear understanding of the reduction mechanism, indicating a clear gap in the scientific knowledge. This knowledge is not just fundamentally important-it is specifically important in applications for bioremediation measures and the sustainable recovery of metal from industrial or mine effluent. To date, about 52 molybdenum-reducing bacteria have been isolated globally. An increasing number of reports have also been published regarding the assimilation of other xenobiotics. This phenomenon is likely to be observed in current and future events in which the remediation of xenobiotics requires microorganisms capable of degrading or transforming multi-xenobiotics. This review aimed to comprehensively catalogue all of the characterizations of molybdenum-reducing microorganisms to date and identify future opportunities and improvements.


Assuntos
Molibdênio , Animais , Biodegradação Ambiental , Oxirredução
3.
Free Radic Res ; 52(9): 1000-1009, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30079776

RESUMO

Ageing is associated with increased oxidative stress accompanied by cognitive decline. The aim of this study was to evaluate oxidative stress biomarkers and their possible relationship with cognitive performances during ageing among the Malay population. Approximately 160 healthy Malay adults aged between 28 and 79 years were recruited around Selangor and Klang Valley. Cognitive function was assessed by Montreal Cognitive Assessment (MoCA), forward digit span (FDS), backward digit span (BDS), digit symbol, Rey Auditory Verbal Learning Test immediate recalled [RAVLT(I)] and delayed recalled [RAVLT(D)], and visual reproduction immediate recalled (VR-I) and delayed recalled (VR-II). DNA damage, plasma protein carbonyl and malondialdehyde (MDA) levels were also determined. Cognitive function test showed significant lower scores of MoCA, BDS, RAVLT(I), RAVLT(D), digit symbol, VR-I, and VR-II in the older age group (60 years old) compared with the 30-, 40-, and 50-year-old group. The extent of DNA damage was sequential with age: 60 > 50 > 40 > 30, whereas protein carbonyl was higher in 40-, 50-, and 60-year-old groups compared with the youngest group (30 years old). However, the MDA level was observed unchanged in all age groups. Approximately 21.88% of the participants had cognitive impairment. Multiple logistic regression analysis revealed that DNA damage and protein carbonyl levels are predictors for cognitive impairment in healthy Malays. In conclusion, cognitive decline occurred in healthy adult Malay population at an early age of 30 years old with corresponding higher DNA damage and protein oxidation.


Assuntos
Envelhecimento/sangue , Disfunção Cognitiva/sangue , Malondialdeído/sangue , Estresse Oxidativo/genética , Adulto , Idoso , Envelhecimento/genética , Envelhecimento/patologia , Disfunção Cognitiva/genética , Disfunção Cognitiva/patologia , Dano ao DNA/genética , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
4.
J Environ Manage ; 183: 182-195, 2016 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-27591845

RESUMO

Biodegradation of agricultural wastes, generated annually from poultry farms and slaughterhouses, can solve the pollution problem and at the same time yield valuable degradation products. But these wastes also constitute environmental nuisance, especially in Malaysia where their illegal disposal on heavy metal contaminated soils poses a serious biodegradation issue as feather tends to accumulate heavy metals from the surrounding environment. Further, continuous use of feather wastes as cheap biosorbent material for the removal of heavy metals from effluents has contributed to the rising amount of polluted feathers, which has necessitated the search for heavy metal-tolerant feather degrading strains. Isolation, characterization and application of a novel heavy metal-tolerant feather-degrading bacterium, identified by 16S RNA sequencing as Alcaligenes sp. AQ05-001 in degradation of heavy metal polluted recalcitrant agricultural wastes, have been reported. Physico-cultural conditions influencing its activities were studied using one-factor-at-a-time and a statistical optimisation approach. Complete degradation of 5 g/L feather was achieved with pH 8, 2% inoculum at 27 °C and incubation period of 36 h. The medium optimisation after the response surface methodology (RSM) resulted in a 10-fold increase in keratinase production (88.4 U/mL) over the initial 8.85 U/mL when supplemented with 0.5% (w/v) sucrose, 0.15% (w/v) ammonium bicarbonate, 0.3% (w/v) skim milk, and 0.01% (w/v) urea. Under optimum conditions, the bacterium was able to degrade heavy metal polluted feathers completely and produced valuable keratinase and protein-rich hydrolysates. About 83% of the feathers polluted with a mixture of highly toxic metals were degraded with high keratinase activities. The heavy metal tolerance ability of this bacterium can be harnessed not only in keratinase production but also in the bioremediation of heavy metal-polluted feather wastes.


Assuntos
Alcaligenes/metabolismo , Plumas/metabolismo , Microbiologia Industrial/métodos , Metais Pesados/toxicidade , Peptídeo Hidrolases/metabolismo , Agricultura , Alcaligenes/efeitos dos fármacos , Alcaligenes/genética , Alcaligenes/isolamento & purificação , Animais , Galinhas , Farmacorresistência Bacteriana Múltipla , Poluentes Ambientais/toxicidade , Concentração de Íons de Hidrogênio , Malásia , RNA Ribossômico 16S , Temperatura , Resíduos
5.
J Environ Biol ; 37(4): 479-84, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-27498490

RESUMO

Acetylcholinesterase (AChE) from the brain tissue of local freshwater fish, Tor tambroides was isolated through affinity purification. Acetylthiocholine iodide (ATCi) was preferable synthetic substrate to purified AChE with highest maximal velocity (V(max)) and lowest biomolecular constant (K(m)) at 113.60 Umg(-1) and 0.0689 mM, respectively, with highest catalytic efficiency ratio (V(max)/K(m)) of 1648.77. The optimum pH was 7.5 with sodium phosphate buffer as medium, while optimal temperature was in the range of 25 to 35 degrees C. Bendiocarp, carbofuran, carbaryl, methomyl and propoxur significantly lowered the AChE activity greater than 50%, and the IC50 value was estimated at inhibitor concentration of 0.0758, 0.0643, 0.0555, 0.0817 and 0.0538 ppm, respectively.


Assuntos
Acetilcolinesterase/metabolismo , Carbamatos/metabolismo , Cyprinidae/metabolismo , Exposição Ambiental , Monitoramento Ambiental/métodos , Inseticidas/metabolismo , Poluentes Químicos da Água/metabolismo , Animais , Concentração Inibidora 50 , Ubiquitina-Proteína Ligases/metabolismo
6.
ScientificWorldJournal ; 2014: 571094, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25401148

RESUMO

Crude extract of ChE from the liver of Puntius javanicus was purified using procainamide-sepharyl 6B. S-Butyrylthiocholine iodide (BTC) was selected as the specific synthetic substrate for this assay with the highest maximal velocity and lowest biomolecular constant at 53.49 µmole/min/mg and 0.23 mM, respectively, with catalytic efficiency ratio of 0.23. The optimum parameter was obtained at pH 7.5 and optimal temperature in the range of 25 to 30°C. The effect of different storage condition was assessed where ChE activity was significantly decreased after 9 days of storage at room temperature. However, ChE activity showed no significant difference when stored at 4.0, 0, and -25°C for 15 days. Screening of heavy metals shows that chromium, copper, and mercury strongly inhibited P. javanicus ChE by lowering the activity below 50%, while several pairwise combination of metal ions exhibited synergistic inhibiting effects on the enzyme which is greater than single exposure especially chromium, copper, and mercury. The results showed that P. javanicus ChE has the potential to be used as a biosensor for the detection of metal ions.


Assuntos
Colinesterases/análise , Fígado/química , Fígado/enzimologia , Metais Pesados/análise , Animais , Colinesterases/metabolismo , Peixes/metabolismo , Metais Pesados/metabolismo
7.
World J Microbiol Biotechnol ; 28(1): 347-52, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22806810

RESUMO

A locally isolated Acinetobacter sp. Strain AQ5NOL 1 was encapsulated in gellan gum and its ability to degrade phenol was compared with the free cells. Optimal phenol degradation was achieved at gellan gum concentration of 0.75% (w/v), bead size of 3 mm diameter (estimated surface area of 28.26 mm(2)) and bead number of 300 per 100 ml medium. At phenol concentration of 100 mg l(-1), both free and immobilized bacteria exhibited similar rates of phenol degradation but at higher phenol concentrations, the immobilized bacteria exhibited a higher rate of degradation of phenol. The immobilized cells completely degrade phenol within 108, 216 and 240 h at 1,100, 1,500 and 1,900 mg l(-1) phenol, respectively, whereas free cells took 240 h to completely degrade phenol at 1,100 mg l(-1). However, the free cells were unable to completely degrade phenol at higher concentrations. Overall, the rates of phenol degradation by both immobilized and free bacteria decreased gradually as the phenol concentration was increased. The immobilized cells showed no loss in phenol degrading activity after being used repeatedly for 45 cycles of 18 h cycle. However, phenol degrading activity of the immobilized bacteria experienced 10 and 38% losses after the 46 and 47th cycles, respectively. The study has shown an increased efficiency of phenol degradation when the cells are encapsulated in gellan gum.


Assuntos
Acinetobacter/metabolismo , Fenol/metabolismo , Acinetobacter/isolamento & purificação , Biodegradação Ambiental , Biotecnologia , Células Imobilizadas/metabolismo , Cinética , Polissacarídeos Bacterianos
8.
Clinics (Sao Paulo) ; 65(12): 1371-7, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-21340229

RESUMO

OBJECTIVES: The aim of this study was to determine the antiproliferative and apoptotic effects of hot water extracts of Chlorella vulgaris on hepatoma cell line HepG2. INTRODUCTION: The search for food and spices that can induce apoptosis in cancer cells has been a major study interest in the last decade. Chlorella vulgaris, a unicellular green algae, has been reported to have antioxidant and anti-cancer properties. However, its chemopreventive effects in inhibiting the growth of cancer cells have not been studied in great detail. METHODS: HepG2 liver cancer cells and WRL68 normal liver cells were treated with various concentrations (0-4 mg/ml) of hot water extract of C. vulgaris after 24 hours incubation. Apoptosis rate was evaluated by TUNEL assay while DNA damage was assessed by Comet assay. Apoptosis proteins were evaluated by Western blot analysis. RESULTS: Chlorella vulgaris decreased the number of viable HepG2 cells in a dose dependent manner (p < 0.05), with an IC50 of 1.6 mg/ml. DNA damage as measured by Comet assay was increased in HepG2 cells at all concentrations of Chlorella vulgaris tested. Evaluation of apoptosis by TUNEL assay showed that Chlorella vulgaris induced a higher apoptotic rate (70%) in HepG2 cells compared to normal liver cells, WRL68 (15%). Western blot analysis showed increased expression of pro-apoptotic proteins P53, Bax and caspase-3 in the HepG2 cells compared to normal liver cells WRL68, and decreased expression of the anti-apoptotic protein Bcl-2. CONCLUSIONS: Chlorella vulgaris may have anti-cancer effects by inducing apoptosis signaling cascades via an increased expression of P53, Bax and caspase-3 proteins and through a reduction of Bcl-2 protein, which subsequently lead to increased DNA damage and apoptosis.


Assuntos
Apoptose/efeitos dos fármacos , Chlorella vulgaris/química , Dano ao DNA/fisiologia , Células Hep G2/efeitos dos fármacos , Extratos Vegetais/farmacologia , Proteínas Reguladoras de Apoptose/metabolismo , Células Hep G2/citologia , Temperatura Alta , Humanos , Proteína Supressora de Tumor p53/metabolismo , Água
9.
Clinics ; 65(12): 1371-1377, 2010. ilus, graf
Artigo em Inglês | LILACS | ID: lil-578579

RESUMO

OBJECTIVES: The aim of this study was to determine the antiproliferative and apoptotic effects of hot water extracts of Chlorella vulgaris on hepatoma cell line HepG2. INTRODUCTION: The search for food and spices that can induce apoptosis in cancer cells has been a major study interest in the last decade. Chlorella vulgaris, a unicellular green algae, has been reported to have antioxidant and anti-cancer properties. However, its chemopreventive effects in inhibiting the growth of cancer cells have not been studied in great detail. METHODS: HepG2 liver cancer cells and WRL68 normal liver cells were treated with various concentrations (0-4 mg/ml) of hot water extract of C. vulgaris after 24 hours incubation. Apoptosis rate was evaluated by TUNEL assay while DNA damage was assessed by Comet assay. Apoptosis proteins were evaluated by Western blot analysis. RESULTS: Chlorella vulgaris decreased the number of viable HepG2 cells in a dose dependent manner (p < 0.05), with an IC50 of 1.6 mg/ml. DNA damage as measured by Comet assay was increased in HepG2 cells at all concentrations of Chlorella vulgaris tested. Evaluation of apoptosis by TUNEL assay showed that Chlorella vulgaris induced a higher apoptotic rate (70 percent) in HepG2 cells compared to normal liver cells, WRL68 (15 percent). Western blot analysis showed increased expression of pro-apoptotic proteins P53, Bax and caspase-3 in the HepG2 cells compared to normal liver cells WRL68, and decreased expression of the anti-apoptotic protein Bcl-2. CONCLUSIONS: Chlorella vulgaris may have anti-cancer effects by inducing apoptosis signaling cascades via an increased expression of P53, Bax and caspase-3 proteins and through a reduction of Bcl-2 protein, which subsequently lead to increased DNA damage and apoptosis.


Assuntos
Humanos , Apoptose/efeitos dos fármacos , Chlorella vulgaris/química , Dano ao DNA/fisiologia , /efeitos dos fármacos , Extratos Vegetais/farmacologia , Proteínas Reguladoras de Apoptose/metabolismo , Temperatura Alta , /citologia , /metabolismo , Água
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