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1.
Braz. j. biol ; 84: e251197, 2024. tab, graf
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1350305

RESUMO

Abstract Birds are among the best bio-indicators, which can guide us to recognize some of the main conservation concerns in ecosystems. Anthropogenic impacts such as deforestation, habitat degradation, modification of landscapes, and decreased quality of habitats are major threats to bird diversity. The present study was designed to detect anthropogenic causative agents that act on waterbird diversity in Tarbella Dam, Indus River, Pakistan. Waterbird censuses were carried out from March 2019 to February 2020 in multiple areas around the dam. A total of 2990 waterbirds representing 63 species were recorded. We detected the highest waterbird richness and diversity at Pehure whereas the highest density was recorded at Kabbal. Human activity impacts seemed to be the main factor determining the waterbird communities as waterbirds were negatively correlated with the greatest anthropogenic impacts. Waterbirds seem to respond rapidly to human disturbance.


Resumo As aves estão entre os melhores bioindicadores, o que pode nos orientar a reconhecer algumas das principais preocupações de conservação dos ecossistemas. Impactos antrópicos como desmatamento, degradação de habitat, modificação de paisagens e diminuição da qualidade dos habitats são as principais ameaças à diversidade de aves. O presente estudo foi desenhado para detectar agentes causadores antropogênicos que atuam na diversidade de aves aquáticas na Represa de Tarbella, rio Indus, Paquistão. Censos de aves aquáticas foram realizados de março de 2019 a fevereiro de 2020 em várias áreas ao redor da barragem. Um total de 2.990 aves aquáticas representando 63 espécies foi registrado. Detectamos a maior riqueza e diversidade de aves aquáticas em Pehure, enquanto a maior densidade foi registrada em Kabbal. Os impactos da atividade humana parecem ser o principal fator determinante das comunidades de aves aquáticas, uma vez que as aves aquáticas foram negativamente correlacionadas com os maiores impactos antrópicos. As aves aquáticas parecem responder rapidamente às perturbações humanas.


Assuntos
Humanos , Ecossistema , Rios , Paquistão , Conservação dos Recursos Naturais
2.
Braz. j. biol ; 842024.
Artigo em Inglês | LILACS-Express | LILACS, VETINDEX | ID: biblio-1469267

RESUMO

Abstract Birds are among the best bio-indicators, which can guide us to recognize some of the main conservation concerns in ecosystems. Anthropogenic impacts such as deforestation, habitat degradation, modification of landscapes, and decreased quality of habitats are major threats to bird diversity. The present study was designed to detect anthropogenic causative agents that act on waterbird diversity in Tarbella Dam, Indus River, Pakistan. Waterbird censuses were carried out from March 2019 to February 2020 in multiple areas around the dam. A total of 2990 waterbirds representing 63 species were recorded. We detected the highest waterbird richness and diversity at Pehure whereas the highest density was recorded at Kabbal. Human activity impacts seemed to be the main factor determining the waterbird communities as waterbirds were negatively correlated with the greatest anthropogenic impacts. Waterbirds seem to respond rapidly to human disturbance.


Resumo As aves estão entre os melhores bioindicadores, o que pode nos orientar a reconhecer algumas das principais preocupações de conservação dos ecossistemas. Impactos antrópicos como desmatamento, degradação de habitat, modificação de paisagens e diminuição da qualidade dos habitats são as principais ameaças à diversidade de aves. O presente estudo foi desenhado para detectar agentes causadores antropogênicos que atuam na diversidade de aves aquáticas na Represa de Tarbella, rio Indus, Paquistão. Censos de aves aquáticas foram realizados de março de 2019 a fevereiro de 2020 em várias áreas ao redor da barragem. Um total de 2.990 aves aquáticas representando 63 espécies foi registrado. Detectamos a maior riqueza e diversidade de aves aquáticas em Pehure, enquanto a maior densidade foi registrada em Kabbal. Os impactos da atividade humana parecem ser o principal fator determinante das comunidades de aves aquáticas, uma vez que as aves aquáticas foram negativamente correlacionadas com os maiores impactos antrópicos. As aves aquáticas parecem responder rapidamente às perturbações humanas.

3.
Eur Rev Med Pharmacol Sci ; 27(24): 12029-12042, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38164865

RESUMO

OBJECTIVE: The objective of the study was to assess the protective effects of barbigerone in ethanol-induced gastric ulcers in rats. MATERIALS AND METHODS: Male Wistar rats (180±20 g) were used in the study (n=06). The rats were randomly divided into different groups, i.e., the normal group, ethanol control, and barbigerone 10 and 20 mg/kg group. Various biochemical parameters were assessed - total acidity and pH values, oxidative stress biomarkers such as superoxide dismutase (SOD), glutathione (GSH), malondialdehyde (MDA), and catalase (CAT) along with markers, i.e., tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6), IL-1ß, intercellular adhesion molecule-1 (ICAM-1) and expression of B-Cell Leukemia/Lymphoma 2 (Bcl-2). Also, histopathology was performed. RESULTS: Treatment with barbigerone in the ethanol-induced-ulcer rats restored the levels of biochemical parameters such as SOD, GSH, MDA, CAT, and markers expression, including TNF-α, IL-6, IL-1ß, ICAM-1, and Bcl-2 with protected against cellular necrosis. CONCLUSIONS: Barbigerone protective effects can be attributed to its ability to reduce oxidative stress and inflammation, as well as promote gastroprotection against ethanol-induced ulcers in rats.


Assuntos
Fator de Necrose Tumoral alfa , Úlcera , Ratos , Masculino , Animais , Fator de Necrose Tumoral alfa/metabolismo , Interleucina-6/metabolismo , Molécula 1 de Adesão Intercelular/metabolismo , Etanol/toxicidade , Ratos Wistar , Antioxidantes/farmacologia , Antioxidantes/metabolismo , Estresse Oxidativo , Glutationa/metabolismo , Superóxido Dismutase/metabolismo , Interleucina-1beta/metabolismo
4.
J Egypt Natl Canc Inst ; 34(1): 29, 2022 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-35811311

RESUMO

BACKGROUND: One of the main limitations of radiation therapy is the resistance of tumor cells. This study aimed at evaluating the relationship between the expression of epidermal growth factor receptor (EGFR) and echinoderm microtubule-associated protein-like 4-anaplastic lymphoma kinase (EML4-ALK) and tumor radiosensitivity in patients with non-small cell lung cancer. METHODS: Medical case files, pathological results for EGFR and EML4-ALK, and computerized tomography scans of patients with NSCLC treated with thoracic radiation therapy were analyzed. RESULTS: The sample size was 101 patients with mean age 58.43 ± 9.89 years. Statistically significant differences were observed in the mean reduction of long tumor diameter during the early treatment phase in EGFR-positive versus EGFR-negative patients (p value = 0.04) and in short tumor diameter during the late treatment phase in EGFR-positive versus EGFR-negative patients (p value = 0.04). CONCLUSION: Patients with overexpression of EGFR mutations are more radiosensitive during the early treatment phase, and EML4-ALK mutations were less radiosensitive regardless of phases.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Idoso , Quinase do Linfoma Anaplásico/genética , Carcinoma Pulmonar de Células não Pequenas/genética , Carcinoma Pulmonar de Células não Pequenas/patologia , Carcinoma Pulmonar de Células não Pequenas/radioterapia , Receptores ErbB/genética , Humanos , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patologia , Neoplasias Pulmonares/radioterapia , Proteínas Associadas aos Microtúbulos/genética , Pessoa de Meia-Idade , Mutação , Proteínas de Fusão Oncogênica/genética
5.
Braz J Biol ; 84: e259582, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35588521

RESUMO

Pheasants are declining everywhere in the world and therefore updated information about their population and habitats are important for conservation and management. The present study was conducted in the Palas Valley, District Kohistan, Pakistan in late spring (May and June) 2020 and early spring (March and April) 2021 to assess the population and anthropogenic stress. The major focus was on three sympatric pheasant species, including Western Horned Tragopan (Tragopan melanocephalus), Himalayan Monal (Lophophorus impejanus), and Koklass Pheasant (Pucrasia macrolopha). We used the "Call Count Method" for the population assessment in the field, and a questionnaire survey was conducted to document the risk assessment of local residents of the valley. The population assessments revealed that the Koklass Pheasant is more adapted to increasing anthropogenic activities and its population appeared more or less similar as 22 years ago. In the past 22 years, Western Tragopan and Himalayan Monal have lost about 40-50% of their populations. Human interference in the form of illegal hunting, deforestation, and overgrazing was found to be common in the valley. The study concludes that the Palas Valley habitat is ideal for pheasant species; however, human interference in the form of urbanization, habitat fragmentation, illegal hunting, and deforestation is occurring at a rapid pace, causing havoc in the pheasant population.


Assuntos
Meio Ambiente , Galliformes , Animais , Humanos , Paquistão , Medição de Risco
6.
Braz. j. biol ; 82: e239449, 2022. tab, graf
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1249271

RESUMO

Alpha amylase, catalyzing the hydrolysis of starch is a ubiquitous enzyme with tremendous industrial applications. A 1698 bp gene coding for 565 amino acid amylase was PCR amplified from Geobacillus thermodenitrificans DSM465, cloned in pET21a (+) plasmid, expressed in BL21 (DE3) strain of E. coli and characterized. The recombinant enzyme exhibited molecular weight of 63 kDa, optimum pH 8, optimum temperature 70°C, and KM value of 157.7µM. On pilot scale, the purified enzyme efficiently removed up to 95% starch from the cotton fabric indicating its desizing ability at high temperature. 3D model of enzyme built by Raptor-X and validated by Ramachandran plot appeared as a monomer having 31% α-helices, 15% ß-sheets, and 52% loops. Docking studies have shown the best binding affinity of enzyme with amylopectin (∆G -10.59). According to our results, Asp 232, Glu274, Arg448, Glu385, Asp34, Asn276, and Arg175 constitute the potential active site of enzyme.


A alfa-amilase, que catalisa a hidrólise do amido, é uma enzima ubíqua com imensas aplicações industriais. Um gene de 1698 pb que codifica a amilase de 565 aminoácidos foi amplificado por PCR, a partir de Geobacillus thermodenitrificans DSM-465, clonado no plasmídeo pET21a (+), expresso na cepa BL21 (DE3) de E. coli e caracterizado. A enzima recombinante exibiu peso molecular de 63 kDa, pH ótimo igual a 8, temperatura ótima de 70° C e valor KM de 157,7 µM. Em escala piloto, a enzima purificada removeu com eficiência até 95% de amido do tecido de algodão, indicando sua capacidade de desengomagem em alta temperatura. O modelo 3D da enzima construída por Raptor-X e validada por Ramachandran plot apareceu como um monômero com 31% de hélices alfa, 15% de folhas beta e 52% de loops. Os estudos de docking mostraram melhor afinidade de ligação da enzima com amilopectina (∆G: - 10,59). De acordo com nossos resultados, Asp 232, Glu274, Arg448, Glu385, Asp34, Asn276 e Arg175 constituem o sítio ativo potencial da enzima.


Assuntos
Escherichia coli/genética , alfa-Amilases/genética , alfa-Amilases/metabolismo , Temperatura , Estabilidade Enzimática , Clonagem Molecular , Geobacillus , Concentração de Íons de Hidrogênio
7.
Braz. j. biol ; 82: e244735, 2022. tab, graf
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1249280

RESUMO

L-Asparaginase catalysing the breakdown of L-Asparagine to L-Aspartate and ammonia is an enzyme of therapeutic importance in the treatment of cancer, especially the lymphomas and leukaemia. The present study describes the recombinant production, properties and anticancer potential of enzyme from a hyperthermophilic archaeon Pyrococcus abyssi. There are two genes coding for asparaginase in the genome of this organism. A 918 bp gene encoding 305 amino acids was PCR amplified and cloned in BL21 (DE3) strain of E. coli using pET28a (+) plasmid. The production of recombinant enzyme was induced under 0.5mM IPTG, purified by selective heat denaturation and ion exchange chromatography. Purified enzyme was analyzed for kinetics, in silico structure and anticancer properties. The recombinant enzyme has shown a molecular weight of 33 kDa, specific activity of 1175 U/mg, KM value 2.05mM, optimum temperature and pH 80°C and 8 respectively. No detectable enzyme activity found when L-Glutamine was used as the substrate. In silico studies have shown that the enzyme exists as a homodimer having Arg11, Ala87, Thr110, His112, Gln142, Leu172, and Lys232 being the putative active site residues. The free energy change calculated by molecular docking studies of enzyme and substrate was found as ∆G ­ 4.5 kJ/mole indicating the affinity of enzyme with the substrate. IC50 values of 5U/mL to 7.5U/mL were determined for FB, caco2 cells and HepG2 cells. A calculated amount of enzyme (5U/mL) exhibited 78% to 55% growth inhibition of caco2 and HepG2 cells. In conclusion, the recombinant enzyme produced and characterized in the present study offers a good candidate for the treatment of cancer. The procedures adopted in the present study can be prolonged for in vivo studies.


A L-asparaginase, que catalisa a degradação da L-asparagina em L-aspartato e amônia, é uma enzima de importância terapêutica no tratamento do câncer, especialmente dos linfomas e da leucemia. O presente estudo descreve a produção recombinante, propriedades e potencial anticancerígeno da enzima de Pyrococcus abyssi, um archaeon hipertermofílico. Existem dois genes que codificam para a asparaginase no genoma desse organismo. Um gene de 918 bp, que codifica 305 aminoácidos, foi amplificado por PCR e clonado na cepa BL21 (DE3) de E. coli usando o plasmídeo pET28a (+). A produção da enzima recombinante foi induzida sob 0,5mM de IPTG, purificada por desnaturação seletiva por calor e cromatografia de troca iônica. A enzima purificada foi analisada quanto à cinética, estrutura in silico e propriedades anticancerígenas. A enzima recombinante apresentou peso molecular de 33 kDa, atividade específica de 1.175 U / mg, valor de KM 2,05 mM, temperatura ótima de 80º C e pH 8. Nenhuma atividade enzimática detectável foi encontrada quando a L-glutamina foi usada como substrato. Estudos in silico mostraram que a enzima existe como um homodímero, com Arg11, Ala87, Thr110, His112, Gln142, Leu172 e Lys232 sendo os resíduos do local ativo putativo. A mudança de energia livre calculada por estudos de docking molecular da enzima e do substrato foi encontrada como ∆G ­ 4,5 kJ / mol, indicando a afinidade da enzima com o substrato. Valores de IC50 de 5U / mL a 7,5U / mL foram determinados para células FB, células caco2 e células HepG2. Uma quantidade de enzima (5U / mL) apresentou inibição de crescimento de 78% a 55% das células caco2 e HepG2, respectivamente. Em conclusão, a enzima recombinante produzida e caracterizada no presente estudo é uma boa possibilidade para o tratamento do câncer. Os procedimentos adotados na presente pesquisa podem ser aplicados para estudos in vivo.


Assuntos
Humanos , Asparaginase/biossíntese , Asparaginase/farmacologia , Pyrococcus abyssi/enzimologia , Antineoplásicos/farmacologia , Especificidade por Substrato , Estabilidade Enzimática , Proteínas Recombinantes/biossíntese , Proteínas Recombinantes/farmacologia , Células CACO-2 , Escherichia coli/genética , Simulação de Acoplamento Molecular , Concentração de Íons de Hidrogênio
8.
Braz. j. biol ; 82: 1-10, 2022. ilus, tab, graf
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1468498

RESUMO

Alpha amylase, catalyzing the hydrolysis of starch is a ubiquitous enzyme with tremendous industrial applications. A 1698 bp gene coding for 565 amino acid amylase was PCR amplified from Geobacillus thermodenitrificans DSM-465, cloned in pET21a (+) plasmid, expressed in BL21 (DE3) strain of E. coli and characterized. The recombinant enzyme exhibited molecular weight of 63 kDa, optimum pH 8, optimum temperature 70°C, and KM value of 157.7µM. On pilot scale, the purified enzyme efficiently removed up to 95% starch from the cotton fabric indicating its desizing ability at high temperature. 3D model of enzyme built by Raptor-X and validated by Ramachandran plot appeared as a monomer having 31% α-helices, 15% β-sheets, and 52% loops. Docking studies have shown the best binding affinity of enzyme with amylopectin (∆G -10.59). According to our results, Asp 232, Glu274, Arg448, Glu385, Asp34, Asn276, and Arg175 constitute the potential active site of enzyme.


A alfa-amilase, que catalisa a hidrólise do amido, é uma enzima ubíqua com imensas aplicações industriais. Um gene de 1698 pb que codifica a amilase de 565 aminoácidos foi amplificado por PCR, a partir de Geobacillus thermodenitrificans DSM-465, clonado no plasmídeo pET21a (+), expresso na cepa BL21 (DE3) de E. coli e caracterizado. A enzima recombinante exibiu peso molecular de 63 kDa, pH ótimo igual a 8, temperatura ótima de 70° C e valor KM de 157,7 µM. Em escala piloto, a enzima purificada removeu com eficiência até 95% de amido do tecido de algodão, indicando sua capacidade de desengomagem em alta temperatura. O modelo 3D da enzima construída por Raptor-X e validada por Ramachandran plot apareceu como um monômero com 31% de hélices alfa, 15% de folhas beta e 52% de loops. Os estudos de docking mostraram melhor afinidade de ligação da enzima com amilopectina (∆G: - 10,59). De acordo com nossos resultados, Asp 232, Glu274, Arg448, Glu385, Asp34, Asn276 e Arg175 constituem o sítio ativo potencial da enzima.


Assuntos
Escherichia coli/genética , Geobacillus , Vetores Genéticos , alfa-Amilases/genética
9.
Braz. j. biol ; 82: 1-9, 2022. ilus, graf, tab
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1468507

RESUMO

L-Asparaginase catalysing the breakdown of L-Asparagine to L-Aspartate and ammonia is an enzyme of therapeutic importance in the treatment of cancer, especially the lymphomas and leukaemia. The present study describes the recombinant production, properties and anticancer potential of enzyme from a hyperthermophilic archaeon Pyrococcus abyssi. There are two genes coding for asparaginase in the genome of this organism. A 918 bp gene encoding 305 amino acids was PCR amplified and cloned in BL21 (DE3) strain of E. coli using pET28a (+) plasmid. The production of recombinant enzyme was induced under 0.5mM IPTG, purified by selective heat denaturation and ion exchange chromatography. Purified enzyme was analyzed for kinetics, in silico structure and anticancer properties. The recombinant enzyme has shown a molecular weight of 33 kDa, specific activity of 1175 U/mg, KM value 2.05mM, optimum temperature and pH 80°C and 8 respectively. No detectable enzyme activity found when L-Glutamine was used as the substrate. In silico studies have shown that the enzyme exists as a homodimer having Arg11, Ala87, Thr110, His112, Gln142, Leu172, and Lys232 being the putative active site residues. The free energy change calculated by molecular docking studies of enzyme and substrate was found as ∆G – 4.5 kJ/mole indicating the affinity of enzyme with the substrate. IC50 values of 5U/mL to 7.5U/mL were determined for FB, caco2 cells and HepG2 cells. A calculated amount of enzyme (5U/mL) exhibited 78% to 55% growth inhibition of caco2 and HepG2 cells. In conclusion, the recombinant enzyme produced and characterized in the present study offers a good candidate for the treatment of cancer. The procedures adopted in the present study can be prolonged for in vivo studies.


A L-asparaginase, que catalisa a degradação da L-asparagina em L-aspartato e amônia, é uma enzima de importância terapêutica no tratamento do câncer, especialmente dos linfomas e da leucemia. O presente estudo descreve a produção recombinante, propriedades e potencial anticancerígeno da enzima de Pyrococcus abyssi, um archaeon hipertermofílico. Existem dois genes que codificam para a asparaginase no genoma desse organismo. Um gene de 918 bp, que codifica 305 aminoácidos, foi amplificado por PCR e clonado na cepa BL21 (DE3) de E. coli usando o plasmídeo pET28a (+). A produção da enzima recombinante foi induzida sob 0,5mM de IPTG, purificada por desnaturação seletiva por calor e cromatografia de troca iônica. A enzima purificada foi analisada quanto à cinética, estrutura in silico e propriedades anticancerígenas. A enzima recombinante apresentou peso molecular de 33 kDa, atividade específica de 1.175 U / mg, valor de KM 2,05 mM, temperatura ótima de 80º C e pH 8. Nenhuma atividade enzimática detectável foi encontrada quando a L-glutamina foi usada como substrato. Estudos in silico mostraram que a enzima existe como um homodímero, com Arg11, Ala87, Thr110, His112, Gln142, Leu172 e Lys232 sendo os resíduos do local ativo putativo. A mudança de energia livre calculada por estudos de docking molecular da enzima e do substrato foi encontrada como ∆G – 4,5 kJ / mol, indicando a afinidade da enzima com o substrato. Valores de IC50 de 5U / mL a 7,5U / mL foram determinados para células FB, células caco2 e células HepG2. Uma quantidade de enzima (5U / mL) apresentou inibição de crescimento de 78% a 55% das células caco2 e HepG2, respectivamente. Em conclusão, a enzima recombinante produzida e caracterizada no presente estudo é uma boa possibilidade para o tratamento do câncer. Os procedimentos adotados na presente pesquisa podem ser aplicados para estudos in vivo.


Assuntos
Anticarcinógenos/análise , Asparaginase/genética , Leucemia/tratamento farmacológico , Linfoma/tratamento farmacológico , Pyrococcus abyssi/enzimologia
10.
Braz. j. biol ; 822022.
Artigo em Inglês | LILACS-Express | LILACS, VETINDEX | ID: biblio-1468685

RESUMO

Abstract Alpha amylase, catalyzing the hydrolysis of starch is a ubiquitous enzyme with tremendous industrial applications. A 1698 bp gene coding for 565 amino acid amylase was PCR amplified from Geobacillus thermodenitrificans DSM-465, cloned in pET21a (+) plasmid, expressed in BL21 (DE3) strain of E. coli and characterized. The recombinant enzyme exhibited molecular weight of 63 kDa, optimum pH 8, optimum temperature 70°C, and KM value of 157.7µM. On pilot scale, the purified enzyme efficiently removed up to 95% starch from the cotton fabric indicating its desizing ability at high temperature. 3D model of enzyme built by Raptor-X and validated by Ramachandran plot appeared as a monomer having 31% -helices, 15% -sheets, and 52% loops. Docking studies have shown the best binding affinity of enzyme with amylopectin (G -10.59). According to our results, Asp 232, Glu274, Arg448, Glu385, Asp34, Asn276, and Arg175 constitute the potential active site of enzyme.


Resumo A alfa-amilase, que catalisa a hidrólise do amido, é uma enzima ubíqua com imensas aplicações industriais. Um gene de 1698 pb que codifica a amilase de 565 aminoácidos foi amplificado por PCR, a partir de Geobacillus thermodenitrificans DSM-465, clonado no plasmídeo pET21a (+), expresso na cepa BL21 (DE3) de E. coli e caracterizado. A enzima recombinante exibiu peso molecular de 63 kDa, pH ótimo igual a 8, temperatura ótima de 70° C e valor KM de 157,7 µM. Em escala piloto, a enzima purificada removeu com eficiência até 95% de amido do tecido de algodão, indicando sua capacidade de desengomagem em alta temperatura. O modelo 3D da enzima construída por Raptor-X e validada por Ramachandran plot apareceu como um monômero com 31% de hélices alfa, 15% de folhas beta e 52% de loops. Os estudos de docking mostraram melhor afinidade de ligação da enzima com amilopectina (G: - 10,59). De acordo com nossos resultados, Asp 232, Glu274, Arg448, Glu385, Asp34, Asn276 e Arg175 constituem o sítio ativo potencial da enzima.

11.
Braz. j. biol ; 822022.
Artigo em Inglês | LILACS-Express | LILACS, VETINDEX | ID: biblio-1468694

RESUMO

Abstract L-Asparaginase catalysing the breakdown of L-Asparagine to L-Aspartate and ammonia is an enzyme of therapeutic importance in the treatment of cancer, especially the lymphomas and leukaemia. The present study describes the recombinant production, properties and anticancer potential of enzyme from a hyperthermophilic archaeon Pyrococcus abyssi. There are two genes coding for asparaginase in the genome of this organism. A 918 bp gene encoding 305 amino acids was PCR amplified and cloned in BL21 (DE3) strain of E. coli using pET28a (+) plasmid. The production of recombinant enzyme was induced under 0.5mM IPTG, purified by selective heat denaturation and ion exchange chromatography. Purified enzyme was analyzed for kinetics, in silico structure and anticancer properties. The recombinant enzyme has shown a molecular weight of 33 kDa, specific activity of 1175 U/mg, KM value 2.05mM, optimum temperature and pH 80°C and 8 respectively. No detectable enzyme activity found when L-Glutamine was used as the substrate. In silico studies have shown that the enzyme exists as a homodimer having Arg11, Ala87, Thr110, His112, Gln142, Leu172, and Lys232 being the putative active site residues. The free energy change calculated by molecular docking studies of enzyme and substrate was found as G 4.5 kJ/mole indicating the affinity of enzyme with the substrate. IC50 values of 5U/mL to 7.5U/mL were determined for FB, caco2 cells and HepG2 cells. A calculated amount of enzyme (5U/mL) exhibited 78% to 55% growth inhibition of caco2 and HepG2 cells. In conclusion, the recombinant enzyme produced and characterized in the present study offers a good candidate for the treatment of cancer. The procedures adopted in the present study can be prolonged for in vivo studies.


Resumo A L-asparaginase, que catalisa a degradação da L-asparagina em L-aspartato e amônia, é uma enzima de importância terapêutica no tratamento do câncer, especialmente dos linfomas e da leucemia. O presente estudo descreve a produção recombinante, propriedades e potencial anticancerígeno da enzima de Pyrococcus abyssi, um archaeon hipertermofílico. Existem dois genes que codificam para a asparaginase no genoma desse organismo. Um gene de 918 bp, que codifica 305 aminoácidos, foi amplificado por PCR e clonado na cepa BL21 (DE3) de E. coli usando o plasmídeo pET28a (+). A produção da enzima recombinante foi induzida sob 0,5mM de IPTG, purificada por desnaturação seletiva por calor e cromatografia de troca iônica. A enzima purificada foi analisada quanto à cinética, estrutura in silico e propriedades anticancerígenas. A enzima recombinante apresentou peso molecular de 33 kDa, atividade específica de 1.175 U / mg, valor de KM 2,05 mM, temperatura ótima de 80º C e pH 8. Nenhuma atividade enzimática detectável foi encontrada quando a L-glutamina foi usada como substrato. Estudos in silico mostraram que a enzima existe como um homodímero, com Arg11, Ala87, Thr110, His112, Gln142, Leu172 e Lys232 sendo os resíduos do local ativo putativo. A mudança de energia livre calculada por estudos de docking molecular da enzima e do substrato foi encontrada como G 4,5 kJ / mol, indicando a afinidade da enzima com o substrato. Valores de IC50 de 5U / mL a 7,5U / mL foram determinados para células FB, células caco2 e células HepG2. Uma quantidade de enzima (5U / mL) apresentou inibição de crescimento de 78% a 55% das células caco2 e HepG2, respectivamente. Em conclusão, a enzima recombinante produzida e caracterizada no presente estudo é uma boa possibilidade para o tratamento do câncer. Os procedimentos adotados na presente pesquisa podem ser aplicados para estudos in vivo.

12.
Braz J Biol ; 84: e251197, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34852136

RESUMO

Birds are among the best bio-indicators, which can guide us to recognize some of the main conservation concerns in ecosystems. Anthropogenic impacts such as deforestation, habitat degradation, modification of landscapes, and decreased quality of habitats are major threats to bird diversity. The present study was designed to detect anthropogenic causative agents that act on waterbird diversity in Tarbella Dam, Indus River, Pakistan. Waterbird censuses were carried out from March 2019 to February 2020 in multiple areas around the dam. A total of 2990 waterbirds representing 63 species were recorded. We detected the highest waterbird richness and diversity at Pehure whereas the highest density was recorded at Kabbal. Human activity impacts seemed to be the main factor determining the waterbird communities as waterbirds were negatively correlated with the greatest anthropogenic impacts. Waterbirds seem to respond rapidly to human disturbance.


Assuntos
Ecossistema , Rios , Conservação dos Recursos Naturais , Humanos , Paquistão
13.
Braz J Biol ; 82: e239449, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34105678

RESUMO

Alpha amylase, catalyzing the hydrolysis of starch is a ubiquitous enzyme with tremendous industrial applications. A 1698 bp gene coding for 565 amino acid amylase was PCR amplified from Geobacillus thermodenitrificans DSM-465, cloned in pET21a (+) plasmid, expressed in BL21 (DE3) strain of E. coli and characterized. The recombinant enzyme exhibited molecular weight of 63 kDa, optimum pH 8, optimum temperature 70°C, and KM value of 157.7µM. On pilot scale, the purified enzyme efficiently removed up to 95% starch from the cotton fabric indicating its desizing ability at high temperature. 3D model of enzyme built by Raptor-X and validated by Ramachandran plot appeared as a monomer having 31% α-helices, 15% ß-sheets, and 52% loops. Docking studies have shown the best binding affinity of enzyme with amylopectin (∆G -10.59). According to our results, Asp 232, Glu274, Arg448, Glu385, Asp34, Asn276, and Arg175 constitute the potential active site of enzyme.


Assuntos
Escherichia coli , alfa-Amilases , Clonagem Molecular , Estabilidade Enzimática , Escherichia coli/genética , Geobacillus , Concentração de Íons de Hidrogênio , Temperatura , alfa-Amilases/genética , alfa-Amilases/metabolismo
14.
Braz J Biol ; 82: e244735, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34076169

RESUMO

L-Asparaginase catalysing the breakdown of L-Asparagine to L-Aspartate and ammonia is an enzyme of therapeutic importance in the treatment of cancer, especially the lymphomas and leukaemia. The present study describes the recombinant production, properties and anticancer potential of enzyme from a hyperthermophilic archaeon Pyrococcus abyssi. There are two genes coding for asparaginase in the genome of this organism. A 918 bp gene encoding 305 amino acids was PCR amplified and cloned in BL21 (DE3) strain of E. coli using pET28a (+) plasmid. The production of recombinant enzyme was induced under 0.5mM IPTG, purified by selective heat denaturation and ion exchange chromatography. Purified enzyme was analyzed for kinetics, in silico structure and anticancer properties. The recombinant enzyme has shown a molecular weight of 33 kDa, specific activity of 1175 U/mg, KM value 2.05mM, optimum temperature and pH 80°C and 8 respectively. No detectable enzyme activity found when L-Glutamine was used as the substrate. In silico studies have shown that the enzyme exists as a homodimer having Arg11, Ala87, Thr110, His112, Gln142, Leu172, and Lys232 being the putative active site residues. The free energy change calculated by molecular docking studies of enzyme and substrate was found as ∆G - 4.5 kJ/mole indicating the affinity of enzyme with the substrate. IC50 values of 5U/mL to 7.5U/mL were determined for FB, caco2 cells and HepG2 cells. A calculated amount of enzyme (5U/mL) exhibited 78% to 55% growth inhibition of caco2 and HepG2 cells. In conclusion, the recombinant enzyme produced and characterized in the present study offers a good candidate for the treatment of cancer. The procedures adopted in the present study can be prolonged for in vivo studies.


Assuntos
Antineoplásicos/farmacologia , Asparaginase , Pyrococcus abyssi , Asparaginase/biossíntese , Asparaginase/farmacologia , Células CACO-2 , Estabilidade Enzimática , Escherichia coli/genética , Humanos , Concentração de Íons de Hidrogênio , Simulação de Acoplamento Molecular , Pyrococcus abyssi/enzimologia , Proteínas Recombinantes/biossíntese , Proteínas Recombinantes/farmacologia , Especificidade por Substrato
15.
Jpn J Radiol ; 35(10): 555-561, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28795273

RESUMO

Radiotherapy is the ionizing radiation used for treatment of cancer and other diseases. Although radiotherapy is the major treatment for cancer, a lot of patients do not undergo radiation due to associated risks such as radiation pneumonitis, cardiovascular complications, development of secondary tumor, and lymphedema. However, the advantages of nanotechnology provide a unique potential to enhance radiotherapeutic performance, in particular by utilizing gold nanoparticles (Au NPs). In this review, we briefly describe the current direction of research towards the use of Au NPs for radiotherapeutic enhancement, combination, monitoring and in side effect reductions.


Assuntos
Ouro/química , Aumento da Imagem/métodos , Nanopartículas Metálicas/uso terapêutico , Neoplasias/radioterapia , Humanos
16.
Genet Mol Res ; 15(2)2016 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-27420957

RESUMO

Mitochondrial DNA (mtDNA) is an important tool used to explore ethnogenetics and the evolutionary history of human populations. In this study, hypervariable segment I (HVSI) from mtDNA was analyzed to establish the genetic lineage of the Hazarewal populations residing in the Mansehra and Abbottabad districts of Northern Pakistan. HVSI was extracted from genetic specimens obtained from 225 unrelated male and female individuals belonging to seven distinct Pakistani ethnic groups (31 Abbassis, 44 Awans, 38 Gujars, 16 Jadoons, 23 Karlals, 33 Syeds, and 40 Tanolis). Eighty-three haplogroups, 39 of which were unique, were identified; haplogroup H was predominantly represented (in 40% of the people), followed by haplogroups M (21.78%), R (16.89%), N (15.56%), L (3.11%), and HV (2.67%). The results revealed a sex-biased genetic contribution from putative West Eurasian, South Asian, and Sub-Saharan populations to the genetic lineage of Hazarewal ancestry, with the effect of Eurasians being predominant. The HVSI nucleotide sequences exhibited some characteristic deletion mutations between 16,022 and 16,193 bp, which is characteristic of specific ethnic groups. HVSI sequence homology showed that Hazarewal populations fall into three major clusters: Syeds and Awans sorted out into cluster I; Tanolis, Gujars, and Karlals segregated in cluster II; and Abbassis and Jadoons in cluster III. Here, we have reported the firsthand genetic information and evolutionary sketch of the selected populations residing alongside the historical Silk Route, which provides a baseline for collating the origin, route of migration, and phylogenetics of the population.


Assuntos
Povo Asiático/genética , DNA Mitocondrial/genética , Polimorfismo Genético , População/genética , Povo Asiático/etnologia , Evolução Molecular , Feminino , Deleção de Genes , Migração Humana , Humanos , Masculino , Paquistão
17.
Acta Biol Hung ; 65(3): 252-64, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25194729

RESUMO

The dynamical fluctuations of biological signals provide a unique window to construe the underlying mechanism of the biological systems in health and disease. Recent research evidences suggest that a wide class of diseases appear to degrade the biological complexity and adaptive capacity of the system. Heart rate signals are one of the most important biological signals that have widely been investigated during the last two and half decades. Recent studies suggested that heart rate signals fluctuate in a complex manner. Various entropy based complexity analysis measures have been developed for quantifying the valuable information that may be helpful for clinical monitoring and for early intervention. This study is focused on determining HRV dynamics to distinguish healthy subjects from patients with certain cardiac problems using symbolic time series analysis technique. For that purpose, we have employed recently developed threshold based symbolic entropy to cardiac inter-beat interval time series of healthy, congestive heart failure and atrial fibrillation subjects. Normalized Corrected Shannon Entropy (NCSE) was used to quantify the dynamics of heart rate signals by continuously varying threshold values. A rule based classifier was implemented for classification of different groups by selecting threshold values for the optimal separation. The findings indicated that there is reduction in the complexity of pathological subjects as compared to healthy ones at wide range of threshold values. The results also demonstrated that complexity decreased with disease severity.


Assuntos
Fibrilação Atrial/fisiopatologia , Eletrocardiografia , Insuficiência Cardíaca/fisiopatologia , Frequência Cardíaca , Processamento de Sinais Assistido por Computador , Adulto , Idoso , Fibrilação Atrial/diagnóstico , Estudos de Casos e Controles , Eletrocardiografia Ambulatorial , Entropia , Feminino , Insuficiência Cardíaca/diagnóstico , Humanos , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Índice de Gravidade de Doença , Fatores de Tempo , Adulto Jovem
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