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1.
Life Sci ; 336: 122316, 2024 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-38035995

RESUMEN

Helicobacter pylori infection is a risk factor for the development of gastric cancer (GC), and the role of co-infection with viruses, such as Epstein-Barr virus, in carcinogenesis cannot be ignored. Furthermore, it is now known that genetic factors such as long non-coding RNAs (lncRNAs) are involved in many diseases, including GC. On the other side, they can also be used as therapeutic goals. Modified lncRNAs can cause aberrant expression of genes encoding proximal proteins, which are essential for the development of carcinoma. In this review, we present the most recent studies on lncRNAs in GC, concentrating on their roles in H. pylori and EBV infections, and discuss some of the molecular mechanisms of these GC-related pathogens. There was also a discussion of the research gaps and future perspectives.


Asunto(s)
Infecciones por Virus de Epstein-Barr , Infecciones por Helicobacter , Helicobacter pylori , ARN Largo no Codificante , Neoplasias Gástricas , Humanos , Herpesvirus Humano 4/genética , Infecciones por Virus de Epstein-Barr/complicaciones , Infecciones por Virus de Epstein-Barr/genética , Neoplasias Gástricas/genética , Neoplasias Gástricas/patología , Helicobacter pylori/genética , ARN Largo no Codificante/genética , Infecciones por Helicobacter/complicaciones , Infecciones por Helicobacter/genética
2.
Curr Mol Med ; 2023 Aug 16.
Artículo en Inglés | MEDLINE | ID: mdl-37587826

RESUMEN

Long non-coding RNAs (lncRNAs) are transcribed RNA molecules longer than 200 nucleotides in length that have no protein-coding potential. They are able to react with DNA, RNA, and protein. Hence they involve in regulating gene expression at the epigenetic, transcriptional, post-transcriptional, and translational levels. LncRNAs have been proven to play an important role in human malignancies and prognostic outcomes. In this review, we will comprehensively and functionally discuss the role of a novel identified lncRNA, namely lncRNA WAPPH located on human chromosome 2q13, in various cancers. Increasing research studies have shown that lncRNA AWPPH is deregulated in different malignancies, including breast cancer, gastric cancer, colorectal cancer, ovarian cancer, bladder cancer, leukemia, and others. LncRNA WAPPH serves as an oncogene in tumorigenesis and the development of cancer. Moreover, lncRNA AWPPH is involved in numerous biological processes of solid and blood cancers. Taken together, based on our scrutiny analysis, lncRNA AWPPH can be regarded as a putative biomarker for diagnosis or therapeutic target in human malignancies.

3.
Saudi Dent J ; 35(5): 553-558, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-37520603

RESUMEN

Introduction: Human teeth are composed mainly of dentin, formed by the odontoblasts. Dentin matrix protein 1 (DMP1) is one of odontoblast differentiation's most important growth factors. Human DMP1 has yet to be completely identified or studied. This study aimed to clone and characterize human DMP1. Materials and methods: The DMP1 gene sequence was prepared and cloned by transfection of human 293 cells. Results: The recombinant DMP1 was purified and characterized. Conclusion: The results suggested its future use in dental tissue regeneration and tissue engineering.

4.
Microb Pathog ; 181: 106153, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-37295483

RESUMEN

Crimean-Congo haemorrhagic fever (CCHF) is a re-emerging viral haemorrhagic fever causing outbreaks in Iran in the last 15 years. In this systematic review and meta-analysis, the status of Crimean-Congo haemorrhagic fever virus (CCHFV) in ticks would be evaluated. PubMed, Google Scholar and Web of Science were searched for peer-reviewed original papers published between 2000 and 1 July 2022. We included papers that evaluated the prevalence of CCHFV in individual ticks using reverse transcription polymerase chain reaction (RT-PCR). The pooled prevalence of CCHFV was 6.0% (95% confidence interval [CI]: 4.5-7.9%), with heterogeneity (I2 = 82.706; P < 0.0001). The prevalence of CCHFV was higher related to regions with above sea level of 1001-1500m (6.4%; 95% CI: 4.3-9.5%), an average temperature of ≤15 °C (8.3%; 95% CI: 5.6-12.0%), latitude of ≥36° (8.1%; 95% CI: 5.2-12.3%), an annual rainfall of 101-300 mm (9.8%; 95% CI: 6.1-15.4%) and humidity of ≥61% (10.2%; 95% CI: 5.1-19.3%). Due to the importance of CCHF, it is better to do new epidemiologic studies on ticks by related organizations and adjacent regions of some provinces in which human cases have been previously reported.


Asunto(s)
Virus de la Fiebre Hemorrágica de Crimea-Congo , Fiebre Hemorrágica de Crimea , Garrapatas , Animales , Humanos , Virus de la Fiebre Hemorrágica de Crimea-Congo/genética , Fiebre Hemorrágica de Crimea/epidemiología , Irán/epidemiología , Humedad
5.
BMC Pediatr ; 23(1): 254, 2023 05 22.
Artículo en Inglés | MEDLINE | ID: mdl-37217902

RESUMEN

OBJECTIVES: Diarrhoea is the most commonly related disease caused by Aeromonas. To improve knowledge on prevalence, this systematic review and meta-analysis was performed to evaluate the global prevalence of Aeromonas in children with diarrhoea worldwide. METHODS: We systematically searched PubMed, Google scholar, Wiley Online Library, ScienceDirect, and Web of sciences to identify all cross-sectional published papers between 2000 and 10 July 2022. After initial scrutinizing, 31 papers reporting the prevalence of Aeromonas in children with diarrhoea were found to be adequate for meta-analysis. The statistical study was accompanied by using random effects models. RESULTS: A total of 5660 identified papers, 31 cross-sectional studies encompassing 38,663 participants were included in the meta-analysis. The pooled prevalence of Aeromonas in children with diarrhoea worldwide was 4.2% (95% CI 3.1-5.6%). In the subgroup analysis, the highest prevalence was seen among children in Upper middle-income countries with pooled prevalence of 5.1% (95% CI 2.8-9.2%). The prevalence of Aeromonas in children with diarrhoea was higher in countries with populations of over 100 million people (9.4%; 95% CI 5.6-15.3%), and water and sanitation quality score of less than 25% (8.8%; 95% CI 5.2-14.4%). Additionally, Cumulative Forest Plot showed a decreasing trend in the prevalence of Aeromonas infection in children with diarrhoea over time (P = 0.0001). CONCLUSION: The results of this study showed a better comprehension of Aeromonas prevalence in children with diarrhoea on a global scale. As well as our findings showed that much work is still required to decline the burden of bacterial diarrhoea in countries with high populations, low-level income, and unsanitary water.


Asunto(s)
Diarrea , Agua , Niño , Humanos , Prevalencia , Estudios Transversales , Diarrea/epidemiología
6.
Biochim Biophys Acta Gen Subj ; 1867(8): 130385, 2023 08.
Artículo en Inglés | MEDLINE | ID: mdl-37230419

RESUMEN

Colorectal cancer (CRC) treatment is dramatically hampered by resistance to oxaliplatin alone or in the combination of irinotecan or 5-fluorouracil and leucovorin. This study aims to design and assess Chitosan/Hyaluronic Acid/Protamine sulfate (CS/HA/PS) polyplexes loaded with CRISPR plasmid for targeting a key gene in cancer drug resistance. Here, recent findings were considered to validate oxaliplatin-resistant CRC-related genes and systems biology approaches employed to detect the critical gene. The polyplexes were characterized according to particle size, zeta potential, and stability. Moreover, carrier toxicity and transfection efficiency were assessed on oxaliplatin-resistant HT-29 cells. The post-transfection evaluations were performed to confirm gene disruption-mediated CRISPR. Eventually, excision cross complementation group 1(ERCC1), a crucial member of the nucleotide excision repair pathway, was selected to be targeted using CRISPR/Cas9 to reverse oxaliplatin resistance in HT-29 cells. CS/HA/PS polyplexes containing CRISPR/Cas9 plasmid exhibited negligible toxicity and comparable transfection efficiency with Lipofectamine™. Following the efficient gene delivery, sequences in CRISPR/Cas9 target sites were altered, ERCC1 was downregulated, and drug sensitivity was successfully restored in oxaliplatin-resistant cells. Findings indicate that CS/HA/PS/CRISPR polyplexes provide a potential strategy for delivering cargo and targeting oxaliplatin resistance-related gene to manipulate drug resistance as a rising concern in cancer therapeutic approaches.


Asunto(s)
Quitosano , Neoplasias Colorrectales , Humanos , Oxaliplatino/farmacología , Oxaliplatino/uso terapéutico , Ácido Hialurónico , Sistemas CRISPR-Cas/genética , Protaminas/genética , Protaminas/uso terapéutico , Redes Reguladoras de Genes , Neoplasias Colorrectales/tratamiento farmacológico , Neoplasias Colorrectales/genética
8.
Int J Biol Macromol ; 229: 696-712, 2023 Feb 28.
Artículo en Inglés | MEDLINE | ID: mdl-36529222

RESUMEN

Dasatinib (DAS) exhibits anti-inflammatory effects by retrieving the balance between inflammatory and anti-inflammatory cytokines secreted by macrophages. The aim of this study was the development of redox-responsive micelles with the potential of passive targeting and on-demand drug release for DAS delivery to macrophages. For this purpose, two molecular weights of chitosan (CHIT) were conjugated to DAS at different molar ratios using 3,3'-dithiodipropionic anhydride (DTDPA) as disulfide bond containing linker to synthesize a series of CHIT-S-S-DAS amphiphilic conjugates. Micelles obtained by the sonication method had particle sizes of 129.3-172.2 nm, zeta potentials of +17.5 to +20.9 mV, drug contents of 0.90-7.20 %, CMC values of 35.3-96.6 µg/ml, and exhibited redox-responsive in vitro drug release. Optimized micelles were non-toxic and dramatically more efficient than non-redox responsive micelles in reducing TNF-α and IL-6 and increasing IL-10 secretion from LPS-stimulated RAW264.7 cells. Furthermore, the redox-responsive micelles were able to reduce the mice paw edema, reduce the plasma levels of pro-inflammatory cytokines and increase plasma level of IL-10, considerably more than free DAS and non-redox responsive micelles in carrageenan-induced mice paw edema model of inflammation.


Asunto(s)
Quitosano , Micelas , Animales , Ratones , Antiinflamatorios , Quitosano/química , Dasatinib/farmacología , Portadores de Fármacos/química , Sistemas de Liberación de Medicamentos/métodos , Interleucina-10 , Oxidación-Reducción , Inflamación/tratamiento farmacológico
9.
Drug Dev Ind Pharm ; 48(1): 29-39, 2022 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-35723593

RESUMEN

OBJECTIVE: Diabetic retinopathy (DR) is a common microvascular complication of diabetes mellitus. This study aimed to compare the effect of sunitinib-loaded poly (glycerol sebacate) (PGS)/gelatin nanoparticles doped in an injectable hydrogel with bevacizumab as a standard treatment of DR. METHODS: The shear-sensitive hydrogel was prepared based on tragacanthic acid (TA) cross-linked with sodium acetate. DR was induced in rats by streptozotocin (STZ), and the animals were injected intravitreally a single dose of 20 µL sunitinib solution in three different concentrations (12.5, 25, and 50 µg/mL), sunitinib-loaded nanoparticles in hydrogel (413 µg/mL) and bevacizumab solution (6.25 mg/mL). The efficacy of the treatments was studied by histological and immunohisitological tests, angiogenesis, and optical coherence tomography (OCT). Vascular endothelial growth factor (VEGF) concentration was measured in the retina. RESULTS: The results revealed that 20 µL of sunitinib with the concentration of 25 µg/mL was effective in DR without any disruption in the retina or any other side effects. This dose was considered the therapeutic dose for nanoparticles. Sunitinib loaded PGS/gelatin nanoparticles that were incorporated in the injectable hydrogel were as effective as bevacizumab in controlling DR. Although sunitinib solution reduced VEGF production and neovascularization in the retina compared to the negative control group, it was not as suitable as the nanoparticles. TA-based hydrogel showed no toxicity on the normal retina, and the angiography and histologic studies confirmed the VEGF results.' CONCLUSIONS: Sunitinib nanoparticles doped in TA hydrogel may be an appropriate substitution of bevacizumab in the treatment of DR.


Asunto(s)
Diabetes Mellitus , Retinopatía Diabética , Nanopartículas , Animales , Bevacizumab/uso terapéutico , Retinopatía Diabética/tratamiento farmacológico , Retinopatía Diabética/metabolismo , Retinopatía Diabética/patología , Gelatina , Hidrogeles , Ratas , Sunitinib/uso terapéutico , Factor A de Crecimiento Endotelial Vascular/metabolismo
10.
World J Microbiol Biotechnol ; 38(2): 29, 2022 Jan 06.
Artículo en Inglés | MEDLINE | ID: mdl-34989886

RESUMEN

Structural engineering of the recombinant thrombolytic drug, Reteplase, and its cost-effective production are important goals in the pharmaceutical industry. In this study, a single-point mutant of the protein was rationally designed and evaluated in terms of physicochemical characteristics, enzymatic activity, as well as large-scale production settings. An accurate homology model of Reteplase was used as the input to appropriate tools to identify the aggregation-prone sites, while considering the structural stability. Selected variants underwent extensive molecular dynamic simulations (total 540 ns) to assess their solvation profile and their thermal stability. The Reteplase-fibrin interaction was investigated by docking. The best variant was expressed in E. coli, and Box-Behnken design was used through response surface methodology to optimize its expression conditions. M72R mutant demonstrated appropriate stability, enhanced enzymatic activity (p < 0.05), and strengthened binding to fibrin, compared to the wild type. The optimal conditions for the variant's production in a bioreactor was shown to be 37 ºC, induction with 0.5 mM IPTG, for 2 h of incubation. Under these conditions, the final amount of the produced enzyme was increased by about 23 mg/L compared to the wild type, with an increase in the enzymatic activity by about 2 IU/mL. This study thus offered a new Reteplase variant with nearly all favorable properties, except solubility. The impact of temperature and incubation time on its large-scale production were underlined as well.


Asunto(s)
Ingeniería Metabólica , Proteínas Recombinantes/biosíntesis , Activador de Tejido Plasminógeno/biosíntesis , Reactores Biológicos , Biotecnología , Escherichia coli/genética , Escherichia coli/metabolismo , Fibrinolíticos/metabolismo , Regulación Bacteriana de la Expresión Génica , Simulación del Acoplamiento Molecular , Simulación de Dinámica Molecular , Mutagénesis , Pliegue de Proteína , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/farmacología , Activador de Tejido Plasminógeno/química , Activador de Tejido Plasminógeno/genética , Activador de Tejido Plasminógeno/farmacología
11.
Adv Biomed Res ; 11: 117, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36798911

RESUMEN

Background: Single-chain fragment variable (scFv) is one of the most commonly used antibody fragments. They offer some advantages over full-length antibodies, including better penetration to target tissues. However, their functional production has been a challenge for manufacturers due to the potential misfolding and formation of inclusion bodies. Here we evaluated the soluble expression and purification of molecular chaperone co-expression. Materials and Methods: E. coli BL21(DE3) cells were co-transformed with the mixture of plasmids pKJE7 and pET22b-scFv by the electroporation method. First, L-arabinose was added to induce the expression of molecular chaperones, and then IPTG was used as an inducer to start the expression of anti-HER2 scFv. The effect of cultivation temperature and IPTG concentration on soluble expression of the protein with or without chaperones was evaluated. The soluble expressed protein was subjected to native purification using the Ni-NTA affinity column. Results: SDS-PAGE analysis confirmed the successful co-expression of anti-HER2-scFv and DnaK/DnaJ/GrpE chaperones. Co-expression with chaperones and low-temperature cultivation synergistically improved the soluble expression of anti-HER2 scFv. Co-expression with chaperone also exhibited an approximately four-fold increase in the final yield of purified soluble protein. Conclusion: The combination of co-expression with chaperones and low temperature presented in this work may be useful for the improvement of commercial production of other scFvs in E. coli as functionally bioactive and soluble form.

12.
Braz. J. Pharm. Sci. (Online) ; 58: e18984, 2022. graf
Artículo en Inglés | LILACS | ID: biblio-1364429

RESUMEN

Interferon-ß-1a (INF-ß-1a) has gained significant attention due to its emerging applications in the treatment of different human diseases. Therefore, many researchers have attempted to produce it in large quantities and also in a biologically active form using different expression systems. In the present study, we aimed to improve the expression level of INF-ß-1a by Pichia pastoris using optimization of culture conditions. The codon-optimized INF-ß- 1a gene was cloned into pPICZαA plasmid under the control of alcohol oxidase I (AOX1) promoter. The protein expression was induced using different concentrations of methanol at different pHs and temperatures. The biological activity of produced protein was evaluated by anti-proliferative assay. The ideal culture conditions for the expression of INF-ß-1a by P. pastoris were found to be induction with 2% methanol at pH 7.0 culture medium at 30 C which yielded a concentration of 15.5 mg/L INF-ß-1a in a shake flask. Our results indicate that differences in glycosylation pattern could result in different biological activities as INF- ß-1a produced by P. pastoris could significantly more reduce the cell viability of HepG-2 cells, a hepatocellular carcinoma cell line, than a commercially available form of this protein produced by CHO


Asunto(s)
Pichia/clasificación , Interferón beta/agonistas , Carcinoma Hepatocelular/patología , Optimización de Procesos , Codón , Células , Carcinoma Hepatocelular , Concentración de Iones de Hidrógeno
13.
BMC Res Notes ; 14(1): 88, 2021 Mar 09.
Artículo en Inglés | MEDLINE | ID: mdl-33750469

RESUMEN

OBJECTIVE: Nosocomial infections (NIs) are known as one of the remarkable problems in all countries. This study is aimed to estimate the prevalence rate of nosocomial bacterial agents with antimicrobial susceptibility pattern in hospitalized patients. This study was conducted from April 2017 to September 2018, on 4029 hospitalized patients. We set out to recognize the commonest bacterial infections and antimicrobial susceptibility patterns of nosocomial infection. RESULTS: Of the 4029 patients, 509 (12.6%) of them were culture positive. Of these Escherichia coli (E. coli) (98.3%) and Staphylococcus epidermidis (S. epidermidis) (37.5%) were the most abundant bacterial identified in the urinary tract and bloodstream cultures respectively, Moreover, Acinetobacter spp. (100%) and Pseudomonas aeruginosa (22.2%) were the most abundant organisms detected in the respiratory system. According to susceptibility testing results, 370 (80.5%) and 264 (57.3%) in Gram-negatives and 44 (91.7%) and 35 (72.9%) in gram positives isolated strains were classified as multidrug-resistant (MDR) and extensive drug-resistant (XDR) strain respectively. On account of the high prevalence of MDR and XDR bacterial species, there is a pressing need for the expansion of new strategies on antibiotic supervision and infection control to introduce new guideline on empirical antibiotic therapy.


Asunto(s)
Infecciones Bacterianas , Infección Hospitalaria , Antibacterianos/farmacología , Antibacterianos/uso terapéutico , Infecciones Bacterianas/tratamiento farmacológico , Infecciones Bacterianas/epidemiología , Infección Hospitalaria/tratamiento farmacológico , Infección Hospitalaria/epidemiología , Estudios Transversales , Farmacorresistencia Bacteriana Múltiple , Escherichia coli , Humanos , Irán/epidemiología , Pruebas de Sensibilidad Microbiana , Estudios Retrospectivos
14.
Biotechnol Appl Biochem ; 68(2): 279-287, 2021 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-32275078

RESUMEN

Sphingosine kinases type 1 (SphK1) is a key enzyme in the phosphorylation of sphingosine to sphingosine 1-phosphate (S1P). Different abnormalities in SphK1 functions may correspond with poor prognosis in various cancers. Additionally, upregulated SphK1/S1P could promote cancer cell proliferation, angiogenesis, mobility, invasion, and metastasis. MicroRNAs as conserved small noncoding RNAs play major roles in cancer initiation, progression, metastasis, etc. Their posttranscriptionally mechanisms could affect the development of cancer growth or tumorigenesis suppression. The growing number of studies has described that various microRNAs can be regulated by SphK1, and its expression level can also be regulated by microRNAs. In this review, the relationship of SphK1 and microRNA functions and their interaction in human malignancies have been discussed. Based on them novel treatment strategies can be introduced.


Asunto(s)
Lisofosfolípidos/metabolismo , MicroARNs/metabolismo , Proteínas de Neoplasias/metabolismo , Neoplasias/metabolismo , Neovascularización Patológica/metabolismo , Fosfotransferasas (Aceptor de Grupo Alcohol)/metabolismo , ARN Neoplásico/metabolismo , Esfingosina/análogos & derivados , Humanos , Neoplasias/irrigación sanguínea , Neoplasias/patología , Esfingosina/metabolismo
15.
J Biomol Struct Dyn ; 39(4): 1321-1333, 2021 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-32098615

RESUMEN

Plasminogen activators (PAs) are widely used for treatment of disorders caused by clot formation. Fibrin specific PAs are safe drugs from this group because of reducing the incidence of hemorrhage. The newer generation of PAs like tenecteplase, reteplase and desmoteplase were designed with the aim of achieving desirable properties such as improving specificity and affinity to fibrin and increasing half-life. Protein engineering and using of theoretical methods can help to rational and reliable design of new PAs with a set of favorable properties. In the present study, two new chimeric reteplase named M1-chr and M2-chr were designed with the aim of enhancing fibrin affinity also some potential properties include of increasing resistance to plasminogen activator inhibitor-1 and decreasing neurotoxicity. So, finger domain of desmoteplase was added to reteplase as a high fibrin specific domain. Some other point mutations were considering to achieve other mentioned properties. Three dimensional structure of wild-type reteplase and mutants were created by homology modeling and were evaluated by molecular dynamic simulation. Then, mutants docked to fibrin by HADDOCK web tools. Result of theoretical section verified the stability of mutants' structures. Also showed better interaction between M1-chr with fibrin than M2-chr. Wild-type and mutants were produced in bacterial expression system. Experimental assessment showed both mutants have appropriate enzymatic activity also 1.9-fold fibrin binding ability compared to wild-type. Therefore, this study offers new thrombolytic drugs with desirable properties specially enhanced fibrin affinity so they can represent a promising future in cost-effective production of favorable thrombolytic drugs.Communicated by Ramaswamy H. Sarma.


Asunto(s)
Fibrina , Activador de Tejido Plasminógeno , Fibrina/farmacología , Fibrinólisis , Fibrinolíticos , Activadores Plasminogénicos/farmacología , Proteínas Recombinantes , Activador de Tejido Plasminógeno/genética , Activador de Tejido Plasminógeno/farmacología
16.
Res Pharm Sci ; 15(4): 331-339, 2020 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-33312211

RESUMEN

BACKGROUND AND PURPOSE: Tobacco etch virus (TEV) protease, a 27 KDa protein, consists of the catalytic domain of nuclear inclusion a (NIa) protein produced by Tobacco etch virus. Because of its unique sequence, TEV protease is used for purging fusion tags from proteins. It also has many advantages such as stability and activity in a board range of temperature and pH and overproduction in Escherichia coli and these benefits make this protease valuable. Despite all these benefits, TEV protease has problems like low solubility (less than 1 mg/mL). There are methods for enhancing protein solubility and in this study, the effect of additives during cell lysis was studied. EXPERIMENTAL APPROACH: Eleven different additives that made twelve different lysis buffers were used and their effect on TEV protease solubility analyzed by Plackett-Burman and response surface methodology methods. FINDINGS / RESULTS: Three best effective additives on TEV solubility (L-proline, sodium selenite, and CuCl2) were selected according to software analysis and the best concentration of them was applied to optimize TEV protease solubility. CONCLUSION AND IMPLICATIONS: The obtained results provided the composition of an optimum solvent for obtaining soluble TEV protease.

17.
Rep Biochem Mol Biol ; 9(1): 82-88, 2020 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-32821755

RESUMEN

BACKGROUND: Occult hepatitis B infection (OBI) is defined as the lack of detectable HBsAg in serum, despite the presence of intrahepatic viral DNA, and low levels of covalently closed circular DNA (cccDNA). Since the hemodialysis patients are at a greater disadvantage if they are a carrier of Hep B, as it can lead to OBI this study was designed to determine the prevalence of OBI in hemodialysis patients residing in Zanjan, Iran. METHODS: We conducted an anti-HBc test (ELISA) on 166 HBsAg negative hemodialysis patient samples. OBI was evaluated using seropositive (anti-HBc and/or anti-HBs) and seronegative (anti-HBc and anti-HBs) using nested PCR. RESULTS: Out of the total hemodialysis patients sampled, the study consisted of 58.4% male and 41.6% female participants. The age of the study group ranged from 58.89±15.49, and had received approximately 28.27±27.43 years of dialysis. Additionally, 5.4% of patients had a history of blood transfusions, while 58.4% were vaccinated against the hepatitis B virus (HBV). Moreover, 23.5% patients were anti-HBc positive, while 76.5% patients tested negative. Lastly, 66.3% of the patients were positive for anti-HBs, whereas 33.7% were negative for anti-HBs. Overall, the study revealed that the prevalence of OBI was 6%, and HBV DNA was detected in 2.1% of individuals who were vaccinated against hepatitis B (p < 0.01). CONCLUSION: Though no significant difference between the prevalence of OBI to the patients' age, sex, duration of dialysis, or history of blood transfusion was identified, however, a strong correlation between the prevalence of OBI to HBV vaccination was found.

18.
Res Pharm Sci ; 15(2): 164-173, 2020 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-32582356

RESUMEN

BACKGROUND AND PURPOSE: Tobacco etch virus (TEV) protease is a protease with high sequence specificity which is useful for the cleavage of fusion proteins. A major limitation of this enzyme is its relatively poor solubility. This study aimed to investigate the effects of some suggested mutations by online tools and molecular dynamics simulation to improve the solubility of TEV protease in vitro. EXPERIMENTAL APPROACH: We designed a rational multi-stage process to determine the solubilizing mutations of TEV protease. At the first stage, all the possible mutations were predicted using online tools such as PoPMuSiC and Eris servers, in which five mutations include N23F, N23L, Q74L, Q74V, and Q74I were suggested for further studies. In the next step, the three dimensional structure of the wild type (WT) and the best mutations were subjected to molecular dynamic simulations to evaluate the dynamic behaviour of the obtained structures. The selected mutation was introduced into the structure using site-directed mutagenesis and expressed in Escherichia coli BL21DE3. After purification, solubility and activity of the purified mutant and WT-TEV proteases were assayed. FINDINGS /RESULTS: By considering the analysis of various factors such as structural and solubility properties, one mutant, N23F, was selected for in vitro studies which led to a 1.5 times increase in the solubility compared to the WT while its activity was decreased somewhat. CONCLUSION AND IMPLICATIONS: We propose N23F mutation, according to computational and experimental analyses for TEV proteases which resulted in a 150% increase in solubility compared to the WT.

19.
Iran J Biotechnol ; 18(4): e2556, 2020 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-34056023

RESUMEN

BACKGROUND: Reteplase, the recombinant form of tissue plasminogen activator, is a thrombolytic drug with outstanding characteristics, while demonstrating limited solubility and reduced plasminogen activation. Previously, we in silico designed a variant of Reteplase with positively supercharged surface, which showed promising stability, solubility and activity. This study was devoted to evaluation of the utility of supercharging technique for enhancing these characteristics in Reteplase. OBJECTIVE: To test the hypothesis that reinforced surface charge of a rationally-designed Reteplase variant will not compromise its stability, will increase its solubility, and will enhance its plasminogen cleavage activity. MATERIALS AND METHODS: Supercharged Reteplase coding sequence was cloned in pDest527 vector and expressed in E. coli BL21 (DE3). The expressed protein was extracted by cell disruption. Inclusion bodies were solubilized using guanidine hydrochloride, followed by dialysis for protein refolding. After confirmation with SDS-PAGE and western blotting, extracted proteins were assayed for solubility and tested for bioactivity. RESULTS: SDS-PAGE and western blot analysis confirmed the successful expression of Reteplase. Western blot experiments showed most of Reteplase expressed in the insoluble form. Plasminogen cleavage assay showed significantly higher activity of the supercharged variant than the wild type protein (P < 0.001). The stability of the supercharged variant was also comparable to the wild type. CONCLUSION: Our findings, i.e. the contribution of the surface supercharging technique to retained stability, enhanced plasminogen cleavage activity, while inefficiently changed solubility of Reteplase, contain implications for future designs of soluble variants of this fibrinolytic protein drug.

20.
Int J Biol Macromol ; 165(Pt B): 2789-2804, 2020 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-33736282

RESUMEN

Drug delivery to posterior segment of eye has always been challenging. The aim of the present study was to provide a novel injectable, shear sensitive hydrogel based on tragacanthic acid (TA) with three kinds of acetate salts as cross-linker. Rheological properties by strain and shear stress sweep measurements and also dynamic rheological experiments including frequency and time sweep measurements were studied. Biological studies comprising, cell culture, Draize test on rabbit eyes and histopathological tests were done. The results showed the optimized hydrogel was biocompatible, injectable and owning acceptable firmness in rest state after injection. Healing time of the hydrogel was 46 s and was shear-sensitive. It showed no cytotoxicity on HUVEC cells. No allergic reaction was seen in Draize test and histological examination showed integrity of the retinal layers with no evidence of pathological changes, such as deformations, degeneration, or inflammation. TA hydrogel is promising in ocular drug delivery.


Asunto(s)
Hidrogeles/administración & dosificación , Tragacanto/química , Animales , Proliferación Celular , Sistemas de Liberación de Medicamentos , Células Endoteliales de la Vena Umbilical Humana , Humanos , Hidrogeles/química , Inyecciones Intraoculares , Masculino , Conejos , Ratas , Reología , Estrés Mecánico
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