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1.
Curr Protoc ; 3(4): e749, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37097192

RESUMO

The most commonly used fungal DNA extraction techniques require enzymatic digestion or hazardous chemicals. Here, we describe a quick non-enzymatic salt-out method that we developed for isolating high-quality DNA from various fungal species. DNA was extracted from four species of typical fungi, including Saccharomyces cerevisiae, Hansenula polymorpha, Candida albicans, and Aspergillus flavus. Results that we obtained from agarose gel electrophoresis and spectrophotometry verified the integrity, high quality, and purity of the extracted DNAs. Also, PCR amplification and restriction enzyme digestion confirmed the efficiency of the extracted DNAs in molecular biology applications. © 2023 Wiley Periodicals LLC. Basic Protocol 1: Yeast and fungal cultivation for DNA extraction Basic Protocol 2: Modified salting out DNA extraction protocol Support Protocol 1: PCR amplification of extracted genomes Support Protocol 2: Digestion with restriction enzyme.


Assuntos
Fenol , Saccharomyces cerevisiae , Clorofórmio , DNA Fúngico/genética , Cloreto de Sódio
2.
Sci Rep ; 12(1): 1959, 2022 02 04.
Artigo em Inglês | MEDLINE | ID: mdl-35121783

RESUMO

Nowadays, the usage of nanoparticles in various fields such as drug delivery, attracts the attention of many researchers in the treatment of cancers. Graphene oxide (GO) is one of the novel drug delivery systems which is used broadly owing to its unique features. In this survey, doxorubicin (DOX) was accompanied by natural medicine, curcumin (CUR), to diminish its side effects and enhance its efficiency. Cytotoxicity assay in human gastric cancer (AGS), prostate cancer (PC3), and ovarian cancer (A2780), was evaluated. Also, the uptake of DOX and CUR into cells, was assessed using a fluorescence microscope. Moreover, real-time PCR was applied for the evaluation of the expression of RB1 and CDK2 genes, which were involved in the cell cycle. In both separate and simultaneous forms, DOX and CUR were loaded with high efficiency and the release behavior of both drugs was pH-sensitive. The higher release rate was attained at pH 5.5 and 42 °C for DOX (80.23%) and CUR (13.06), respectively. The intensity of fluorescence in the free form of the drugs, was higher than the loaded form. In the same concentration, the free form of CUR and DOX were more toxic than the loaded form in all cell lines. Also, free drugs showed more impact on the expression of RB1 and CDK2 genes. Co-delivery of CUR and DOX into the mentioned cell lines, was more effective than the free form of CUR and DOX due to its lower toxicity to normal cells.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Curcumina/administração & dosagem , Doxorrubicina/administração & dosagem , Portadores de Fármacos , Grafite/química , Neoplasias/tratamento farmacológico , Polímeros Responsivos a Estímulos , Protocolos de Quimioterapia Combinada Antineoplásica/química , Protocolos de Quimioterapia Combinada Antineoplásica/metabolismo , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Curcumina/química , Curcumina/metabolismo , Quinase 2 Dependente de Ciclina/genética , Quinase 2 Dependente de Ciclina/metabolismo , Doxorrubicina/química , Doxorrubicina/metabolismo , Composição de Medicamentos , Liberação Controlada de Fármacos , Feminino , Humanos , Concentração de Íons de Hidrogênio , Cinética , Masculino , Neoplasias/genética , Neoplasias/metabolismo , Neoplasias/patologia , Proteínas de Ligação a Retinoblastoma/genética , Proteínas de Ligação a Retinoblastoma/metabolismo , Ubiquitina-Proteína Ligases/genética , Ubiquitina-Proteína Ligases/metabolismo
3.
EXCLI J ; 18: 485-498, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31423128

RESUMO

Cancer therapies using defects in homologous recombination (HR) DNA repair pathway of tumor cells are not yet approved to be applicable in patients with malignancies other than BRCA1/2-mutated tumors. This study was designed to determine the efficacy of combination therapy of a histone deacetylase inhibitor, valproic acid (VPA) and a novel PARP inhibitor AZD2461 in both PC-3 (PTEN-mutated) and DU145 (PTEN-unmutated) prostate cancer cell lines. The Trypan blue dye exclusion assay and the tetrazolium-based colorimetric (MTT) assay were performed to measure the cytotoxicity while combination effects were assessed based on Chou-Talalay's principles. Flow-cytometric assay determined the type of cell death. The real-time PCR analysis was used to evaluate the alterations in mRNA levels of HR-related genes while their protein levels were measured using the ELISA method. γ-H2AX levels were determined as a marker of DNA damage. We observed a synergistic relationship between VPA and AZD2461 in all affected fractions of PC-3 cells (CI<0.9), but not in DU145 cells (CI>1.1). Annexin-V staining analysis revealed a significant induction of apoptosis when PC-3 cells were treated with VPA+AZD2461 (p<0.05). Both mRNA and protein levels of Rad51 and Mre11 were significantly decreased in PC-3 cells co-treated with VPA+AZD2461 while enhanced H2AX phosphorylation was found in PC-3 cells after 12 and 24 hours of co-treatment (p<0.05). Our findings established a preclinical rationale for selective targeting of HR repair pathways by a combination of VPA and AZD2461 as a mechanism for reducing the HR pathway sufficiency in PTEN-mutated prostate cancer cells.

4.
Toxicon ; 164: 82-86, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30991063

RESUMO

Conventional drug delivery systems have many limitations including cytotoxicity and affecting non-specific cells. Cell-targeting peptides (CTPs) as a potential class of targeting moiety have some advantages over previous targeting moieties such as monoclonal antibodies, offer additional benefits to design systems using CTPs. Here we have engineered listeriolysin O (LLO) pore-forming toxin by adding a luteinizing hormone-releasing hormone (LHRH) targeting peptide to its N-terminus. Two versions of the toxin, with and without targeting peptide, were sub-cloned into a bacterial expression plasmid. BL21 DE3 cells were used for induction of expression and recombinant proteins were purified using nickel-immobilized metal affinity chromatography column. In order to treat MDA-MB-231 and SKOV3 cell lines as LHRH receptor positive and negative cells, two mentioned LLO toxins were used to evaluate their cytotoxicity and specificity. Our results reveal that the IC50 of LLO toxin on MDA-MB-231 and SKOV3 cells was 0.32 and 0.41 µg/ml respectively. Furthermore, IC50 of fusion LHRH-LLO toxin on the cells was 0.88 and 19.55 µg/ml. Cytotoxicity of engineered LHRH-LLO toxin on negative cells was significantly 48-fold lower than wild-type LLO toxin. But this difference has been lowered to only 2.7-fold less cytotoxicity in positive cells. To the best of our knowledge, the current work as the first study regarding engineered toxin revealed that CDC family members could be used to target the specific cell-type.


Assuntos
Antineoplásicos/farmacocinética , Toxinas Bacterianas/farmacocinética , Sistemas de Liberação de Medicamentos/métodos , Hormônio Liberador de Gonadotropina/farmacocinética , Proteínas de Choque Térmico/farmacocinética , Proteínas Hemolisinas/farmacocinética , Antineoplásicos/administração & dosagem , Antineoplásicos/farmacologia , Toxinas Bacterianas/administração & dosagem , Toxinas Bacterianas/farmacologia , Linhagem Celular Tumoral , Eritrócitos/efeitos dos fármacos , Escherichia coli/metabolismo , Proteínas de Choque Térmico/administração & dosagem , Proteínas de Choque Térmico/farmacologia , Proteínas Hemolisinas/administração & dosagem , Proteínas Hemolisinas/farmacologia , Hemólise , Humanos , Estrutura Molecular , Receptores LHRH/metabolismo , Proteínas Recombinantes
5.
Curr Pharm Des ; 25(3): 333-342, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30864499

RESUMO

Glioblastoma multiforme (GBM) is the most common primary malignant brain tumor. Despite standard multimodality treatment, the highly aggressive nature of GBM makes it one of the deadliest human malignancies. The anti-cancer effects of dietary phytochemicals like curcumin provide new insights to cancer treatment. Evaluation of curcumin's efficacy against different malignancies including glioblastoma has been a motivational research topic and widely studied during the recent decade. In this review, we discuss the recent observations on the potential therapeutic effects of curcumin against glioblastoma. Curcumin can target multiple signaling pathways involved in developing aggressive and drug-resistant features of glioblastoma, including pathways associated with glioma stem cell activity. Notably, combination therapy with curcumin and chemotherapeutics like temozolomide, the GBM standard therapy, as well as radiotherapy has shown synergistic response, highlighting curcumin's chemo- and radio-sensitizing effect. There are also multiple reports for curcumin nanoformulations and targeted forms showing enhanced therapeutic efficacy and passage through blood-brain barrier, as compared with natural curcumin. Furthermore, in vivo studies have revealed significant anti-tumor effects, decreased tumor size and increased survival with no notable evidence of systemic toxicity in treated animals. Finally, a pharmacokinetic study in patients with GBM has shown a detectable intratumoral concentration, thereby suggesting a potential for curcumin to exert its therapeutic effects in the brain. Despite all the evidence in support of curcumin's potential therapeutic efficacy in GBM, clinical reports are still scarce. More studies are needed to determine the effects of combination therapies with curcumin and importantly to investigate the potential for alleviating chemotherapy- and radiotherapy-induced adverse effects.


Assuntos
Neoplasias Encefálicas/tratamento farmacológico , Curcumina/uso terapêutico , Glioblastoma/tratamento farmacológico , Animais , Terapia Combinada , Humanos
6.
Iran J Basic Med Sci ; 20(4): 380-385, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29026495

RESUMO

OBJECTIVES: A newly-introduced protein toxin from a sea anemone, namely fragaceatoxin C is a protein with molecular weight of 20 kDa and pore-forming capability against cell membranes has recently grasped great attentions for its function. In this study, its coding sequence cloned as a fusion protein with His-tag for simple production and rapid purification. MATERIALS AND METHODS: After PCR amplification using NcoI and HindIII-harboring primers, the gene fragment was cloned into pET-28a(+). Escherichia coli BL21 was used for expression of constructed vector and toxin expression was verified by SDS-PAGE. For one-step purification Ni-NTA sepharose affinity chromatography was employed. For examination of purified toxin function, RBC hemolytic test was conducted. RESULTS: The results showed that the FraC-coding gene was successfully cloned between NcoI and HindIII restriction sites and purified with affinity chromatography. Densitometric analysis represented the purity of approximately 97%. Hemolytic test indicated the purified FraC had remarkable lytic activity on RBC and almost lysed 50% of cells at the concentration value of 6.25 nM. CONCLUSION: The results indicated that not only purified toxin preserved its activity during expression and purification processes but also exerted its function at lower concentrations so that even the 0.09 nM displayed hemolytic effect.

7.
J Parasit Dis ; 40(4): 1571-1574, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27876985

RESUMO

Cutaneous leishmaniasis is one of the important skin diseases with diverse clinical manifestations. With an incidence of 0.7-1.3 million cases annually, this disease is often reported from six countries, including Iran. Accordingly, the purpose of this study was to evaluate the anti-leishmanial effect of the three plant hydroalcoholic extracts including fleawort (Plantago psyllium L.), savory (Satureja hortensis L.) and tarragon (Artemisia dracunculus L.) on Leishmania major promastigotes. The hydroalcoholic extract from each plant was extracted and its anti-leishmanial effect was evaluated in different concentrations (100-1000 µg/ml) and at various hours (24, 48 and 72 h). Savory herb inhibitory concentration 50 % (IC50) at 24, 48 and 72 h was 790.81, 398.11 and 298.42 µg/ml, respectively. In addition, tarragon herb IC50 at 24, 48 and 72 h was 962.03, 688.36 and 585.51 µg/ml, respectively. Moreover, the fleawort extract was showed the lowest effect, considering that its effect at the concentration of 1000 µg/ml was 48 % after 72 h (P > 0.05). Furthermore, the statistical analysis showed a significant difference for interaction between concentration and time regarding the tarragon and savory extracts with a P value of lower than 0.05. According to the results, the anti-leishmanial effect of the tarragon and savory extracts may make it possible to use them in the treatment of cutaneous leishmaniasis as a complementary or alternative therapy; however, further studies are necessary and should be evaluated in cell culture and in vivo conditions to confirm it.

8.
Mol Med ; 22: 258-270, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27249008

RESUMO

Single chain antibodies (scFvs), which contain only the variable domains of full-length antibodies, are relatively small molecules that can be used for selective drug delivery. In this review, we display how scFv antibodies help improve the specificity and efficiency of drugs. Small interfering RNA (siRNA) delivery using scFv-drug fusion peptides, siRNA delivery using scFv-conjugated nanoparticles, targeted delivery using scFv-viral peptide- fusion proteins, use of scFv in fusion with cell penetrating peptides for effective targeted drug delivery, scFv-mediated targeted delivery of inorganic nanoparticles, scFv-mediated increase of tumor killing activity of granulocytes, use of scFv for tumor imaging, site-directed conjugation of scFv molecules to drug carrier systems, use of scFv to relieve pain, use of scFv for increasing drug loading efficiency are among the topics that are discussed here.

9.
J Cancer Res Ther ; 12(1): 155-60, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27072230

RESUMO

AIM OF STUDY: Embelin and celastrol, inhibitors of XIAP and NF-κB proteins respectively, have been derived from natural sources and shown anti-tumor activities against different cancer cell lines. Some interactions have recently been discovered between XIAP and NF-κB pathways, but the effects of these inhibitors in combination have not been investigated yet. We have studied possible synergistic effects of embelin in combination with celastrol, in an acute myeloid leukemia model, HL-60 cell line. MATERIALS AND METHODS: Cytotoxicity of embelin and celastrol, separately and in combination, was determined by MTT assay and flow cytometry. Chou-Talalay's method was used to assess the synergistic effect of two components. Immunocytochemistry and western blot analysis of the two tumor marker proteins. (survivin and COX-2) was also performed to investigate downstream effects of two components. RESULTS: Analysis of MTT assay and flow cytometry showed that there is a substantial synergistic effect in some affected fractions of drug-treated HL-60. cells, while in other affected fractions a mild synergism or additive effect was observed. Immunocytochemistry and western blot analysis revealed that the expression of survivin and COX-2 proteins was reduced in treated cells. CONCLUSION: Embelin and celastrol showed potent antitumor activity and synergistic effects in combination. Therefore targeting XIAP and NF-κB pathways simultaneously can be investigated in more detail to make use of embelin and celastrol as a combination therapy of cancer.


Assuntos
Benzoquinonas/administração & dosagem , Leucemia Mieloide Aguda/tratamento farmacológico , Triterpenos/administração & dosagem , Proteínas Inibidoras de Apoptose Ligadas ao Cromossomo X/genética , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sinergismo Farmacológico , Células HL-60 , Humanos , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/patologia , NF-kappa B/antagonistas & inibidores , NF-kappa B/genética , Triterpenos Pentacíclicos , Transdução de Sinais/efeitos dos fármacos , Proteínas Inibidoras de Apoptose Ligadas ao Cromossomo X/antagonistas & inibidores
10.
Protein J ; 33(5): 465-73, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25213023

RESUMO

Calprotectin (CP) is widely considered to have diverse roles including growth inhibitory and apoptosis induction in a number of tumor cell lines and antimicrobial activities. As CP has been proposed to bind metal ions with high affinity, we have studied its functional and primarily its structural behavior upon Zn(2+) and Mn(2+) chelation solely and along with Ca(2+). We employed fluorescence spectroscopy and circular dichroism to determine the resulting modifications. Based upon our findings it is clear that treating CP with ions effectively weakened its natural growth inhibitory activity. Moreover, structural analysis of Zn(2+) and Mn(2+)-treated CPs indicated remarkable alterations in the regular secondary structures in favor of irregular structures while Zn(2+) and Mn(2+) treatment of CP after incubation with Ca(2+) displayed no remarkable shifts. Tertiary structure investigation using fluorescence spectroscopy showed that CP undergoes conformational changes upon Zn(2+) and Mn(2+) treatment whereby Trp residues of protein is slightly exposed to the hydrophilic environment, compactness of CP is compromised, whereas in Ca(2+)-treated CP, the tertiary structure integrity is intact upon Zn(2+) and Mn(2+) chelation. Interestingly, CP structural modifications upon Zn(2+) and Mn(2+) treatment was significantly comparable, probably due to similar radii and charges of ions. Taken all together, we have concluded that CP maintains its normal nature in Ca(2+)-loaded state when treated with Zn(2+) and Mn(2+) ions. It can be suggested that Ca(2+) not only stabilize CP structure but also helps CP to keep its structure upon metal ions chelation which is involved in host organism defense system.


Assuntos
Cátions/metabolismo , Complexo Antígeno L1 Leucocitário/química , Complexo Antígeno L1 Leucocitário/metabolismo , Manganês/metabolismo , Zinco/metabolismo , Cálcio/química , Cálcio/metabolismo , Cátions/química , Dicroísmo Circular , Humanos , Manganês/química , Ligação Proteica , Conformação Proteica , Estabilidade Proteica , Zinco/química
11.
Artigo em Inglês | MEDLINE | ID: mdl-24555931

RESUMO

Because they are monovalent for antigen, single chain antibodies display a different antibody-antigen interaction pattern from that of full-length antibodies. Using the law of mass action and considering the antibody-antigen binding pattern at OD-100% and OD-50% points, we introduced a formula for estimating single chain antibody affinity. Sigmoid curves of optical density values versus antibody concentrations were drawn and used to determine antibody concentrations at OD-50% points using statistical software SigmaPlot. The OD-50% points were then used to calculate the affinity via the mathematical formula. A software-adapted format of the equation is also presented for further facilitation of the calculation process. The accuracy of this method for affinity calculation was proved by surface plasma resonance. This method offers a precise evaluation of antibody affinity without requiring special material or apparatus, making it possible to be performed in any biological laboratory with minimum facilities.


Assuntos
Anticorpos/sangue , Afinidade de Anticorpos/imunologia , Reações Antígeno-Anticorpo/imunologia , Anticorpos de Cadeia Única/imunologia , Ensaio de Imunoadsorção Enzimática/métodos , Humanos , Anticorpos de Cadeia Única/análise , Software , Ressonância de Plasmônio de Superfície
12.
Appl Biochem Biotechnol ; 171(7): 1805-18, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23999738

RESUMO

Anabeana variabilis phenylalanine ammonia lyase has just recently been discovered and introduced in clinical trials of phenylketonuria enzyme replacement therapy for its outstanding kinetic properties. In the present study, kinetic stabilization of this therapeutically important enzyme has been explored by introduction of a disulfide bond into the structure. Site-directed mutagenesis was performed with quick-change PCR method. Recombinant wild-type and mutated enzymes were expressed in Escherichia coli, and his-tagged proteins were affinity purified. Formation of disulfide bond was confirmed by Ellman's method, and then chemical unfolding, kinetic behavior, and thermal inactivation of mutated enzyme were compared with the wild type. Based on our results, the Q292C mutation resulted in a significant improvement in kinetic stability and resistance against chemical unfolding of the enzyme while kinetic parameters and pH profile of enzyme activity were remained unaffected. The results of the present study provided an insight towards designing phenylalanine ammonia lyases with higher stability.


Assuntos
Anabaena/enzimologia , Fenilalanina Amônia-Liase/química , Fenilalanina Amônia-Liase/genética , Engenharia de Proteínas/métodos , Anabaena/genética , Dissulfetos/química , Estabilidade Enzimática , Guanidina/farmacologia , Cinética , Modelos Moleculares , Mutação , Conformação Proteica , Desdobramento de Proteína/efeitos dos fármacos
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