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1.
Artigo em Inglês | MEDLINE | ID: mdl-38689030

RESUMO

Longitudinal right ventricular free wall strain (RVFWS) has been identified as an independent prognostic marker in patients with pulmonary hypertension. Little is known however about the prognostic value of RVFWS in patients with sickle cell (SC) disease, particularly during exercise. We therefore examined the prognostic significance of RVFWS both at rest and with exercise in patients with SC disease and normal resting systolic pulmonary artery pressure (SPAP). Consecutive patients with SC disease referred for bicycle ergometer stress echocardiography (SE) were enrolled ftom July 2019 to January 2021. All patients had measurable tricuspid regurgitation velocity (TRV). Conventional echocardiography parameters, left ventricular global longitudinal strain (LVGLS), RVFWS, and ventriculoarterial coupling indices (TAPSE/SPAP and RVFWS/SPAP) were assessed at rest and peak exercise. Repeat SE was performed at a median follow-up of 2 years. The cohort consisted of 87 patients (mean age was 31 ± 11 years, 66% females). All patients had normal resting TRV < 2.8 m/s, RVFWS and LVGLS at baseline. There were 23 (26%) patients who had peak stress RVFWS < 20%. They had higher resting and peak stress TRV and SPAP, but lower resting and peak stress TAPSE/SPAP, RVFWS/SPAP, and LVGLS as well as lower peak stress cardiac output when compared to patients with peak stress RVFWS ≥ 20% (p < 0.05). Patients with baseline peak stress RVFWS < 20% had a significant decrease in exercise performance at follow-up (7.5 ± 2.7 min at baseline vs. 5.5 ± 2.8 min at follow-up, p < 0.001). In the multivariate analysis, baseline peak stress RVFWS was the only independent predictor of poorer exercise performance at follow-up [odds ratio 8.2 (1.2, 56.0), p = 0.033]. Among patients with SC disease who underwent bicycle ergometer SE, a decreased baseline value of RVFWS at peak stress predicted poorer exercise time at follow-up.

2.
Mol Biotechnol ; 65(3): 433-440, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35980593

RESUMO

One of the most important factor that affects the efficient using of baculoviruses as a biopesticide is their sensitivity to UV irradiation. In this study, a photolyase gene (phr) of 1.4 kbp DNA fragment was cloned and characterized from Spodoptera littoralis granulovirus, an Egyptian isolate (SpliGV-EG1). A sequence of 466 amino acid were deduced when the gene was completely sequenced with a predicted molecular mass of ~ 55 kDa. Transcriptional regulation analyses revealed that phr transcripts were detected early at 6-h post-infection (hpi) and remained detectable until 72 hpi, suggesting their transcriptional regulation from a putative early promoter motif. An approximately ~ 55 kDa protein fragment was expressed from phr-induced bacterial culture and detected by SDS-PAGE and western blotting. In addition, direct exposure to UV irradiation resulted in a twofold decrease in SpliGV-EG1 occlusion bodies activation compared with Spodoptera littoralis nucleopolyhedrovirus (SpliNPV) occlusion bodies which decreased with about 129-fold after exposure to UV irradiation based on median lethal concentration value (LC50). The obtained results suggested that the presence of photolyase gene possibly alters the inactivation of SpliGV-EG1-occluded bodies by UV irradiation. These results support the role and application of the photolyase protein to improve the damaged DNA repair mechanism as well as resistance of SpliGV to UV light inactivation.


Assuntos
Desoxirribodipirimidina Fotoliase , Granulovirus , Animais , Granulovirus/genética , Desoxirribodipirimidina Fotoliase/genética , Spodoptera/genética , Baculoviridae/genética , Regiões Promotoras Genéticas
3.
Biotechnol Lett ; 44(12): 1507-1517, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36319880

RESUMO

Serological assays for SARS-CoV-2 are being utilized at an exponential rate for surveillance programs. This enterprise was designed to develop and validate a qualitative immunochromatographic test, via the Lateral Flow Assay (LFA), for detection of immunoglobulins M and G (IgM and IgG) against both nucleocapsid (N) and the receptor-binding domain (RBD) of the spike protein of SARS-CoV-2. Both targeted proteins were cloned and expressed in baculovirus expression system utilizing insect cells Sf9. The recombinant RBD and N proteins were purified and conjugated with gold nanoparticles (AuNPs) to set up the coating antigens pad. Both anti-human IgG and IgM were dispensed on nitrocellulose membrane to capture human antibodies in serum samples. A home-made dispensing system was developed to draw identical test and control lines. The validity of the developed LFA was verified by testing serum samples from 103 convalescent COVID-19 patients who were PCR positive for SARS-CoV-2 along with 28 control serum samples. The developed strips showed distinctive bands for IgM and IgG of both proteins (RBD and N) in positive samples. The sensitivity of RBD-based LFA was 70.9% and 39.8% for IgG and IgM, respectively, with a specificity of 100% for both. The N-based LFA exhibited a sensitivity of 73.8% and 35.9% for IgG and IgM, respectively, while its specificity was 75% and 100% for IgG and IgM, respectively. Our developed LFA could afford a tool for surveillance programs in low-resource countries. Moreover, it might be functional for rapid and inexpensive monitoring of the anti-SARS-CoV-2 antibodies in the sera of vaccinated individuals.


Assuntos
COVID-19 , Nanopartículas Metálicas , Humanos , SARS-CoV-2/genética , Ouro , COVID-19/diagnóstico , Glicoproteína da Espícula de Coronavírus/genética , Baculoviridae/genética , Proteínas de Transporte , Nucleocapsídeo , Imunoglobulina G , Imunoglobulina M
4.
Mol Immunol ; 141: 287-296, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34915268

RESUMO

As the second wave of COVID-19 launched, various variants of Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) have emerged with a dramatic global spread amongst millions of people causing unprecedented case fatalities and economic shut-downs. That initiated a necessity for developing specific diagnostics and therapeutics along with vaccines to control such a pandemic. This endeavor describes generation of murine derived recombinant single-chain fragment variable (scFv) as a monoclonal antibody (MAb) platform targeting the receptor binding domain (RBD) of Spike protein of SARS-CoV-2. A specific synthesized RBD coding sequence was cloned and expressed in Baculovirus expression system. The recombinant RBD (rRBD) was ascertained to be at the proper encoding size of ∼ 600bp and expressed protein of the molecular weight of ∼ 21KDa. Purified rRBD was proved genuinely antigenic and immunogenic, exhibiting specific reactivity to anti-SARS-CoV-2 antibody in an indirect enzyme-linked immunosorbent assay (ELISA), and inducing strong seroconversion in immunized mice. The scFv phage display library against rRBD was successfully constructed, revealing ∼ 90 % recombination frequency, and great enriching factor reaching 88 % and 25 % in polyclonal Ab-based and MAb-based ELISAs, respectively. Typically, three unique scFvs were generated, selected, purified and molecularly identified. That was manifested by their: accurate structure, close relation to the mouse immunoglobulin (Ig) superfamily, right anchored six complementarily-determining regions (CDRs) as three within variable heavy (vH) and variable light (vL) regions each, and proper configuration of the three-dimensional (3D) structure. Besides, their expression downstream in a non-suppressive amber codon of E. coli strain SS32 created a distinct protein band at an apparent molecular weight of ∼ 27KDa. Moreover, the purified scFvs showed authentic immunoreactivity and specificity to both rRBD and SARS-CoV-2 in western blot and ELISA. Accordingly, these developed scFvs platform might be a functional candidate for research, inexpensive diagnostics and therapeutics, mitigating spread of COVID-19.


Assuntos
Enzima de Conversão de Angiotensina 2/metabolismo , Anticorpos Monoclonais/imunologia , Anticorpos Antivirais/imunologia , Teste Sorológico para COVID-19 , COVID-19/diagnóstico , Técnicas de Visualização da Superfície Celular , Epitopos/imunologia , Receptores Virais/metabolismo , SARS-CoV-2/imunologia , Anticorpos de Cadeia Única/imunologia , Glicoproteína da Espícula de Coronavírus/imunologia , Sequência de Aminoácidos , Animais , Anticorpos Monoclonais/biossíntese , Anticorpos Antivirais/sangue , Especificidade de Anticorpos , Baculoviridae , COVID-19/prevenção & controle , Escherichia coli , Feminino , Vetores Genéticos , Camundongos , Camundongos Endogâmicos BALB C , Modelos Moleculares , Biblioteca de Peptídeos , Conformação Proteica , Domínios Proteicos , Proteínas Recombinantes/biossíntese , Proteínas Recombinantes/química , Proteínas Recombinantes/imunologia , Alinhamento de Sequência , Homologia de Sequência de Aminoácidos , Anticorpos de Cadeia Única/biossíntese , Glicoproteína da Espícula de Coronavírus/química , Glicoproteína da Espícula de Coronavírus/genética , Glicoproteína da Espícula de Coronavírus/metabolismo
5.
Virus Genes ; 57(1): 72-82, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33400101

RESUMO

During an ongoing outbreak of Foot-and-Mouth Disease Virus (FMDV), it is crucial to distinguish naturally infected from vaccinated seropositive animals. This would support clinical assessment and punctual vigilance. Assays based on 3ABC non-structural protein as an antigen are reliable for this intention. However, the insolubility and degradation of recombinant 3ABC during expression and purification are serious challenges. In this study, alternatively to expressing the recombinant 3ABC (r3ABC), we expressed the 3AB coding sequence (~672 bp) as a recombinant protein (r3AB) with a molecular mass of ~26 KDa. Analytical data from three-dimensional structure, hydrophilicity, and antigenic properties for 3ABC and 3AB exhibited the 3C protein as a hydrophobic, while 3AB as a hydrophilic and highly antigenic protein. The expressed r3AB was recovered as a completely soluble matter after merely native purification, unlike the full expressed r3ABC. Immunoreactivity of r3AB to anti-FMDV antibody in infected sera with different FMDV serotypes was confirmed by the western blot and indirect ELISA. Besides, the authentic antigenicity of purified r3AB was demonstrated through its ability to induce specific seroconversion in mice. Summarily, the removal of 3C: has influenced neither 3D structure nor antigenic properties of the purified r3AB, overcame insolubility and degradation of the r3ABC, and generated a potential superior antigen (r3AB) for herd screening of animals to any FMDV serotype.


Assuntos
Proteases Virais 3C , Doenças dos Bovinos/prevenção & controle , Vírus da Febre Aftosa/imunologia , Febre Aftosa/prevenção & controle , Proteínas Recombinantes , Proteínas não Estruturais Virais , Proteases Virais 3C/genética , Proteases Virais 3C/imunologia , Animais , Bovinos , Camundongos , Proteínas Recombinantes/genética , Proteínas Recombinantes/imunologia , Proteínas não Estruturais Virais/genética , Proteínas não Estruturais Virais/imunologia
6.
AMB Express ; 10(1): 208, 2020 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-33237335

RESUMO

The search for effective and bioactive antimicrobial molecules to  encounter the medical need for new antibiotics is an encouraging area of research. Plant defensins are small cationic, cysteine-rich peptides with a stabilized tertiary structure by disulfide-bridges and characterized by a wide range of biological functions. The heterologous expression of Egyptian maize defensin (MzDef) in Escherichia coli and subsequent purification by glutathione affinity chromatography yielded 2 mg/L of recombinant defensin peptide. The glutathione-S-transferase (GST)-tagged MzDef of approximately 30 kDa in size (26 KDa GST + ~ 4 KDa MzDef peptide) was immunodetected with anti-GST antibodies. The GST-tag was successfully cleaved from the MzDef peptide by thrombin, and the removal was validated by the Tris-Tricine gel electrophoresis. The MzDef induced strong growth inhibition of Rhizoctonia solani, Fusarium verticillioides, and Aspergillus niger by 94.23%, 93.34%, and 86.25%, respectively, whereas relatively weak growth inhibitory activity of 35.42% against Fusarium solani was recorded. Moreover, strong antibacterial activities were demonstrated against E. coli and Bacillus cereus and the moderate activities against Salmonella enterica and Staphylococcus aureus at all tested concentrations (0.1, 0.2, 0.4, 0.8, 1.6, and 3.2 µM). Furthermore, the in vitro MTT assay exhibited promising anticancer activity against all tested cell lines (hepatocellular carcinoma, mammary gland breast cancer, and colorectal carcinoma colon cancer) with IC50 values ranging from 14.85 to 29.85 µg/mL. These results suggest that the recombinant peptide MzDef may serve as a potential alternative antimicrobial and anticancer agent to be used in medicinal application.

7.
Saudi J Biol Sci ; 27(5): 1363-1367, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32346346

RESUMO

Throughout the vegetative life of Bacillus thuringiensis, vegetative insecticidal proteins (Vip) are produced and secreted. In the present study, the vip3 gene isolated from Bacillus thuringiensis, an Egyptian isolate, was successfully amplified (2.4 kbp) and expressed using bacterial expression system. The molecular mass of the expressed protein was verified using SDS-PAGE and western blot analysis. Whiteflies were also screened for susceptibility to the expressed Vip3 protein (LC50). In addition, ST50 was determined to assess the kill speed of the expressed Vip3 protein against whiteflies compared to the whole vegetative proteins. The results showed that the potency of whole B. thuringiensis vegetative proteins against whiteflies was slightly higher than the expressed Vip3 protein with 4.7-fold based on LC50 value. However, the ST50 parameter showed no significant difference between both the B. thuringiensis vegetative proteins and the expressed Vip3 alone. The results showed that the vip3 gene was successfully expressed in an active form which showed high susceptibility to whiteflies based on the virulence parameters LC50 and ST50. To our knowledge, this study showed for the first time the high toxicity of the expressed Vip3 proteins of B. thuringiensis toward whiteflies as a hopeful and promising bio-control agent.

8.
PeerJ ; 8: e8946, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32341896

RESUMO

Foot-and-mouth disease virus (FMDV) is one of the most devastating animal viruses that affect livestock worldwide. The 1B capsid of FMDV has been widely used to detect and confirm the infection. In the present study, the sequence coding for 1B subunit of FMDV capsid was expressed in insect cells using the baculovirus expression system under the polyhedrin (polh) promoter. The expression of 1B capsid protein was validated in the culture filtrate of insect cells using SDS-PAGE and western blotting. The culture filtrate containing recombinant 1B capsid (r1B) was used as a coated antigen in an indirect enzyme-linked immunosorbent assay (ELISA). The antigenicity and specificity of r1B against SAT 2 serotype-specific antibodies were assessed. Our results revealed that a protein concentration as low as 25 ng could detect SAT 2-specific antibodies in ELISA. The results highlight the application of insect cells developed r1B protein in the detection of FMDV. Further studies are required to determine the ability of r1B to detect other FMDV serotypes.

9.
Mol Immunol ; 118: 132-141, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31881424

RESUMO

Control of Infectious bursal disease virus (IBDV) in endemic countries has been based on early immunization of chicks using conventional live or inactivated vaccines that became not fully effectual and have biosafety concerns. This endeavor seeks generating a recombinant chimeric protein merging the projection domain (PD) of IBDV VP2 capsid with the fragment crystallizable (Fc) of avian IgY (FcIgY), in maize as a prospective poultry edible vaccine. The PD sequence was built on the basis of very virulent IBDV isolates circulating in Egypt. After optimization of codon-usage in maize, sequences of PD and FcIgY were effectively expressed in two elites of yellow maize via bombardment transformation in immature embryos. Chimeric protein amount in stable transgenic samples ranged from1.36% to 3.03% of the total soluble protein based on tissue age and maize cultivar. IBDV VP2 coding sequence was amplified from viral RNA, cloned, and expressed in E. coli. A group of Balb/C mice were hyper-immunized with purified recombinant VP2 protein for raising anti- recombinant VP2 antibodies (anti-rVP2 Ab). Proper expression in maize and immunoreactivity of the chimeric protein (PD-FcIgY) to chicken anti- IBDV and anti-rVP2 Ab were confirmed by both direct and indirect double antibody sandwich (DAS)-ELISAs as well as western blotting. Seeds of regenerated transgenic maize will be validated for chickens as edible vaccination in further studies.


Assuntos
Galinhas/imunologia , Imunoglobulinas/imunologia , Vírus da Doença Infecciosa da Bursa/imunologia , Vacinas de Plantas Comestíveis/imunologia , Sequência de Aminoácidos , Animais , Anticorpos Antivirais/imunologia , Infecções por Birnaviridae/imunologia , Proteínas do Capsídeo/imunologia , Egito , Escherichia coli/imunologia , Feminino , Camundongos , Camundongos Endogâmicos BALB C , Doenças das Aves Domésticas/imunologia , Estudos Prospectivos , Proteínas Recombinantes/imunologia , Alinhamento de Sequência , Vacinação/métodos , Vacinas de Produtos Inativados/imunologia , Proteínas Estruturais Virais/imunologia , Vacinas Virais/imunologia , Zea mays
10.
Sci Rep ; 9(1): 10135, 2019 07 12.
Artigo em Inglês | MEDLINE | ID: mdl-31300744

RESUMO

Foot-and-mouth disease virus (FMDV) is one of the most devastating viral pathogens of cloven-hoofed animals. The detection of antibodies (Ab) against FMDV structural proteins (SP) using virus neutralization test (VNT) and liquid-phase blocking ELISA (LPBE) is the standard procedure in use for monitoring seroconversion in animals post vaccination, the prevalence of infection-surveillance, proving clinical cases and seronegative status of FMDV-free/naïve-animals prior transportation. However, due to variations within SP of FMDV serotypes, each serotype-specific Ab should be detected separately which is laborious and time-consuming. Accordingly, it is crucial to develop a sensitive, rapid, and accurate test capable of detecting FMDV-specific Ab, regardless its serotype. This study describes the heterologous expression of VP2 protein in E. coli, and its evaluation as a capture antigen in a simple indirect ELISA for serotype-independent detection of anti-FMDV Ab. Sequence analysis revealed that the VP2-coding sequence is considerably conserved among FMDV serotypes. The recombinant VP2 (rVP2), a 22 kDa polypeptide, was purified to near homogeneity by affinity chromatography under native conditions. Immunoreactivity of the rVP2 was confirmed by using a panel of positive sera including sera from animals vaccinated with the local trivalent vaccine and guinea pig FMDV antiserum, which is routinely used as tracing/detecting Ab in LPBE testing. The results obtained from the VP2-based ELISA were comparable to those determined by VNT and LPBE standard diagnostic assays. Specificity and sensitivity of rVP2 in capturing anti-FMDV Ab were 98.3% and 100%, respectively. The developed VP2-ELISA is proved reliable and time-efficient assay for detection of FMDV seropositive animals, regardless the FMDV serotype that can be implemented in a combination with VNT and/or LPBE for rapid diagnosis of an ongoing FMDV infection.


Assuntos
Proteínas do Capsídeo/imunologia , Vírus da Febre Aftosa/imunologia , Febre Aftosa/virologia , Proteínas Recombinantes/imunologia , Animais , Antígenos Virais/genética , Proteínas do Capsídeo/genética , Proteínas do Capsídeo/metabolismo , Bovinos , Egito , Ensaio de Imunoadsorção Enzimática/métodos , Ensaio de Imunoadsorção Enzimática/normas , Feminino , Febre Aftosa/diagnóstico , Vírus da Febre Aftosa/genética , Soros Imunes , Camundongos Endogâmicos BALB C , Engenharia de Proteínas/métodos , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Sorogrupo , Vacinas Virais/imunologia
11.
Virology ; 533: 145-154, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-31170612

RESUMO

Foot-and-mouth disease virus (FMDV) exhibits a high degree of antigenic diversity among its serotypes, requiring several anti-FMDV antibodies for its laboratory diagnosis, which complicated the used techniques. To conquer this cumbersome, we developed a new panel of different single-chain fragment variable (scFv) for serotype-independent detection of FMDV. The recombinant VP2 capsid protein, as a relatively conserved protein among FMDV serotypes, was expressed in E. Coli, and injected in mice. Spleen's RNA was extracted for isolating the coding sequences of IgG variable domains that were assembled into repertoires of scFv. Phage library displaying scFv was constructed with ∼1.9 × 108 plaque forming units. Characterization of the library showed eight of unique scFvs, which were expressed as bacterial periplasmic proteins with apparent molecular weight of ∼27 kDa. Our data revealed the broad-spectrum binding affinity of the eight scFvs as both coating and tracing antibodies to FMDV serotypes A, O, and SAT 2.


Assuntos
Proteínas do Capsídeo/imunologia , Vírus da Febre Aftosa/isolamento & purificação , Febre Aftosa/virologia , Anticorpos de Cadeia Única/análise , Sequência de Aminoácidos , Animais , Anticorpos Antivirais/análise , Anticorpos Antivirais/imunologia , Feminino , Febre Aftosa/diagnóstico , Vírus da Febre Aftosa/classificação , Vírus da Febre Aftosa/genética , Vírus da Febre Aftosa/imunologia , Humanos , Imunização , Camundongos , Camundongos Endogâmicos BALB C , Biblioteca de Peptídeos , Sorogrupo , Anticorpos de Cadeia Única/genética , Anticorpos de Cadeia Única/imunologia
12.
PLoS One ; 14(3): e0213580, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30849110

RESUMO

Diarrheic diseases account for the annual death of approximately 1.9 million children under the age of 5 years, and it is a major cause of work absenteeism in developed countries. As diarrheagenic bacteria, enteropathogenic Escherichia coli (EPEC) attach to cells in the small intestine, causing local disappearance of microvilli and inducing the formation of actin-rich pedestals that disrupt the intestinal barrier and help EPEC adhere to and infect intestinal cells. Antibiotics and other bioactive compounds can often be found by analyzing traditional medicines. Here a crude aqueous extract of Hibiscus sabdariffa, which typically grows in subtropical and tropical areas and is a popular medicinal tisane in many countries, was analyzed for antibacterial activity against EPEC. In standard microdilution assays, the extract showed a minimum inhibitory concentration of 6.5 mg/ml against EPEC growth. Time-kill kinetics assays demonstrated significant 24 h bactericidal activity at 25 mg/ml. The extract is able to impede pedestal induction. Not only did the extract inhibit preformed pedestals but it prevented pedestal induction as well. Remarkably, it also promoted the formation of EPEC filaments, as observed with other antibiotics. Our results in vitro support the potential of Hibiscus sabdariffa as an antimicrobial agent against EPEC.


Assuntos
Antibacterianos/farmacologia , Escherichia coli Enterotoxigênica/crescimento & desenvolvimento , Escherichia coli Enterotoxigênica/ultraestrutura , Hibiscus/química , Extratos Vegetais/farmacologia , Antibacterianos/química , Extratos Vegetais/química
13.
Saudi J Biol Sci ; 25(4): 733-738, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29740238

RESUMO

Psorosis is a damaging disease of citrus that is widespread in many parts of the world. Citrus psorosis virus (CPsV), the type species of the genus Ophiovirus, is the putative causal agent of psorosis. Detection of CPsV by laboratory methods, serology in particular is a primary requirement for large-scale surveys but their production has been impaired by the difficulty of obtaining sufficient clean antigen for immunization. Specific PAbs against coat protein were produced in E. coli using recombinant DNA approach. The full length CP gene fragment was amplified by RT-PCR using total RNA extracted from CPsV infected citrus leaves and CP specific primers. The obtained product (1320bp) was cloned, sequenced and sub-cloned into pET-30(+) expression vector. Expression was induced and screened in different bacterial clones by the presence of the expressed protein (48kDa) and optimized in one clone. Expressed CP was purified using batch chromatography under denaturing conditions. Specificity of expressed protein was demonstrated by ELISA before used as antigen for raising PAbs in mice. Specificity of the raised PAbs to CPsV was verified by ELISA and western blotting. The raised PAbs were showed highly effectiveness in screening by ELISA comparing with the commercial antibodies purchased from Agritest, Valanzano, Italy. The expression of CPsV CP gene in E. coli, production of PAbs using recombinant protein as an antigen, the suitability of these antibodies for use in immunodiagnostics against the CPsV Egyptian isolate have been accomplished in this work.

14.
3 Biotech ; 7(4): 269, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28794924

RESUMO

DNA encoding the coat protein (CP) of an Egyptian isolate of tomato yellow leaf curl virus (TYLCV) was inserted into the genome of Autographa californica nucleopolyhedrovirus (AcNPV) under the control of polyhedrin promoter. The generated recombinant baculovirus construct harboring the coat protein gene was characterized using PCR analysis. The recombinant coat protein expressed in infected insect cells was used as a coating antigen in an indirect Enzyme-linked immunosorbent assay (ELISA) and dot blot to test its utility for the detection of antibody generated against TYLCV virus particles. The results of ELISA and dot blot showed that the TYLCV-antibodies reacted positively with extracts of infected cells using the recombinant virus as a coating antigen with strong signals as well as the TYLCV infected tomato and beat plant extracts as positive samples. Scanning electron microscope examination showed that the expressed TYLCV coat protein was self-assembled into virus-like particles (VLPs) similar in size and morphology to TYLCV virus particles. These results concluded that, the expressed coat protein of TYLCV using baculovirus vector system is a reliable candidate for generation of anti-CP antibody for inexpensive detection of TYLCV-infected plants using indirect CP-ELISA or dot blot with high specificity.

15.
Biotechnol J ; 11(9): 1209-20, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27313150

RESUMO

Hairy root (HR) cultures derived from Agrobacterium rhizogenes transformation of plant tissues are an advantageous biotechnological manufacturing platform due to the accumulation of recombinant proteins in an otherwise largely protein free culture medium. In this context, HRs descending from transgenic Nicotiana tabacum plants were successfully used for the production of several functional mAbs with plant-type glycans. Here, we expressed the tumor-targeting monoclonal antibody mAb H10 in HRs obtained either by infecting a transgenic N. tabacum line expressing H10 with A. rhizogenes or a glyco-engineered N. benthamiana line (ΔXTFT) with recombinant A. rhizogenes carrying mAb H10 heavy and light chain cDNAs. Selected HR clones derived from both plants accumulated mAb H10 in the culture medium with similar yields (2-3 mg/L). N-glycosylation profiles of antibodies purified from HR supernatant revealed the presence of plant-typical complex structures for N. tabacum-derived mAb H10 and of GnGn structures lacking xylose and fucose for the ΔXTFT-derived counterpart. Both antibody glyco-formats exhibited comparable antigen binding activities. Collectively, these data demonstrate that the co-infection of ΔXTFT Nicotiana benthamiana with recombinant A. rhizogenes is an efficient procedure for the generation of stable HR cultures expressing the tumor-targeting mAb H10 with a human-compatible glycosylation profile, thus representing an important step towards the exploitation of root cultures for the production of 'next generation' human therapeutic antibodies.


Assuntos
Anticorpos Monoclonais/biossíntese , Nicotiana/genética , Raízes de Plantas/genética , Polissacarídeos/química , Agrobacterium tumefaciens/genética , Agrobacterium tumefaciens/crescimento & desenvolvimento , Anticorpos Monoclonais/química , Anticorpos Monoclonais/genética , Fucose/metabolismo , Glicosilação , Humanos , Neoplasias/metabolismo , Raízes de Plantas/crescimento & desenvolvimento , Raízes de Plantas/microbiologia , Plantas Geneticamente Modificadas/crescimento & desenvolvimento , Plantas Geneticamente Modificadas/metabolismo , Plantas Geneticamente Modificadas/microbiologia , Proteínas Recombinantes/metabolismo , Nicotiana/crescimento & desenvolvimento , Nicotiana/microbiologia
16.
Can J Cardiol ; 31(12): 1497.e7-1497.e14, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26255216

RESUMO

BACKGROUND: Most commonly, left atrial appendage (LAA) occlusion procedures are performed using transesophageal echocardiography (TEE) guidance and general anaesthesia. Intracardiac echocardiography (ICE) offers potential advantages over TEE, however, ICE-guided LAA occlusion experience is limited and has been typically performed from a right-sided location where LAA visualization might be suboptimal. We sought to evaluate the efficacy and safety of percutaneous LAA occlusion using ICE guidance performed from the left atrium. METHODS: Thirty-seven patients with atrial fibrillation, significant risk for stroke, and long-term contraindication to anticoagulation underwent LAA closure with the Amplatzer Cardiac Plug (St Jude Medical, Inc, St Paul, MN) with mild sedation and ICE guidance. The ICE catheter was introduced in the left atrium through a second transseptal puncture. Patients underwent preprocedural TEE to rule out thrombus and 3-month follow-up TEE to assess occlusion grade. Patient characteristics, procedural data, effectiveness of ICE imaging, quality of occlusion, and complications were prospectively recorded. RESULTS: Procedural success was achieved in 36 of 37 patients (97%). Closure was complete or near complete (grade ≥3 according to ICE and angiography) in all cases where the device was released. In all cases, ICE imaging yielded good LAA and surrounding structure visualization and adequate procedural guidance. Three major procedural or in-hospital complications occurred. Median length of stay was 1 day. Follow-up TEE documented the absence of any residual peri-device leak in all but 1 (29 of 30) case. CONCLUSION: Initial experience suggests LAA occlusion with the Amplatzer Cardiac Plug using ICE guidance from the left atrium is feasible, reproducible, and safe.


Assuntos
Apêndice Atrial/diagnóstico por imagem , Apêndice Atrial/cirurgia , Fibrilação Atrial/diagnóstico por imagem , Fibrilação Atrial/cirurgia , Cateterismo Cardíaco/métodos , Ecocardiografia/métodos , Dispositivo para Oclusão Septal , Ultrassonografia de Intervenção/métodos , Idoso , Idoso de 80 Anos ou mais , Sedação Consciente , Estudos de Viabilidade , Feminino , Seguimentos , Humanos , Tempo de Internação , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias/etiologia
17.
BMC Plant Biol ; 15: 183, 2015 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-26194497

RESUMO

BACKGROUND: Wheat is considered the most important cereal crop all over the world. The wheat weevil Sitophilus granarius is a serious insect pests in much of the wheat growing area worldwide and is responsible for significant loss of yield. Avidin proteins has been proposed to function as plant defense agents against insect pests. RESULTS: A synthetic avidin gene was introduced into spring wheat (Triticum aestivum L.) cv. Giza 168 using a biolistic bombardment protocol. The presence and expression of the transgene in six selected T0 transgenic wheat lines were confirmed at the molecular level. Accumulation of avidin protein was detected in transgenic plants compared to non-transgenic plants. Avidin transgene was stably integrated, transcribed and translated as indicated by Southern blot, ELISA, and dot blot analyses, with a high level of expression in transgenic wheat seeds. However, no expression was detected in untransformed wheat seeds. Functional integrity of avidin was confirmed by insect bioassay. The results of bioassay using transgenic wheat plants challenged with wheat weevil revealed 100 % mortality of the insects reared on transgenic plants after 21 days. CONCLUSION: Transgenic wheat plants had improved resistance to Sitophilus granarius.


Assuntos
Proteínas Aviárias/genética , Avidina/genética , Controle Biológico de Vetores , Triticum/fisiologia , Gorgulhos , Animais , Proteínas Aviárias/metabolismo , Avidina/metabolismo , Expressão Gênica , Controle de Insetos , Plantas Geneticamente Modificadas/genética , Plantas Geneticamente Modificadas/fisiologia , Triticum/genética
18.
Crit Care ; 18(5): 558, 2014 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-25358417

RESUMO

INTRODUCTION: The occurrence of cardiac dysfunction is common after subarachnoid hemorrhage (SAH) and was hypothesized to be related to the release of endogenous catecholamines. The aim of this prospective study was to evaluate the relationship between endogenous catecholamine and cardiac dysfunction at the onset and during the first week after SAH. METHODS: Forty consecutive patients admitted for acute SAH without known heart disease were included. Catecholamine plasma concentrations and transthoracic echocardiography (TTE) were documented on admission, on day 1 (D1), and day 7 (D7). RESULTS: At baseline, 24 patients had a World Federation of Neurosurgical Societies score (WFNS) of one or two; the remaining 16 had a WFNS between three and five. Twenty patients showed signs of cardiac dysfunction on admission, including six with left ventricle (LV) systolodiastolic dysfunction and 14 with pure LV diastolic dysfunction. On admission, norepinephrine, epinephrine, dopamine, B-type Natriuretic Peptide (BNP) and Troponin Ic (cTnI) plasmatic levels were higher in patients with the higher WFNS score and in patients with altered cardiac function (all P <0.05). Among patients with cardiac injury, heart function was restored within one week in 13 patients, while seven showed persistent LV diastolic dysfunction (P = 0.002). Plasma BNP, cTnI, and catecholamine levels exerted a decrease towards normal values between D1 and D7. CONCLUSION: Our findings show that cardiac dysfunction seen early after SAH was associated with both a rapid and sustained endogenous catecholamine release and WFNS score. SAH-induced cardiac dysfunction was regressive over the first week and paralleled the normalization of catecholamine concentration.


Assuntos
Cardiomiopatias/etiologia , Catecolaminas/sangue , Hemorragia Subaracnóidea/complicações , Adulto , Idoso , Biomarcadores/sangue , Cardiomiopatias/sangue , Ecocardiografia/métodos , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Peptídeo Natriurético Encefálico/sangue , Hemorragia Subaracnóidea/sangue , Fatores de Tempo , Troponina I/sangue , Disfunção Ventricular Esquerda/sangue
20.
Can J Cardiol ; 29(4): 441-7, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23265095

RESUMO

BACKGROUND: The Implantation of Autologous CD133(+) Stem Cells in Patients Undergoing CABG (IMPACT-CABG) trial is investigating the feasibility, safety, and efficacy of intramyocardial injections of autologous CD133(+) stem cells during coronary artery bypass grafting (CABG) in patients with chronic ischemic cardiomyopathy. We are reporting the results of the first 5 open-label patients. METHODS: Bone marrow was harvested from iliac crests and stem cells were isolated using the CliniMACS CD133(+) Reagent System (Miltenyi Biotec, GmbH, Bergisch Gladbach, Germany). Patients received CABG, followed by CD133(+) cellular injection in the revascularized hypokinetic myocardium. RESULTS: Five males New York Heart Association (NYHA) class III patients aged 64 ± 10 years were treated. Immunomagnetic cell processing allowed an average of 100 ± 48-fold enrichment in CD133(+) cells, with 92 ± 11% recovery after selection. Mean number of CD133(+) cells injected was 8.4 ± 1.2 million. There were no protocol-related complications during the 18-month follow-up and all patients improved to NYHA class I. Six-month echocardiography showed no significant improvement in left ventricular ejection fraction (34 ± 2% at baseline vs 38 ± 12%: P = 0.50). However, cardiac magnetic resonance showed that systolic wall thickening increased from 15.0 ± 10.5% to 29.0 ± 22.1% (P = 0.01). In addition, mean segmental wall thickness also improved in comparison with baseline (10.7 ± 2.7% to 12.1 ± 4.8%; P < 0.01). CONCLUSIONS: This work represents the first Canadian experience with CD133(+) stem cells for the treatment of chronic ischemic cardiomyopathy. These results demonstrate the initial safety and feasibility of the IMPACT-CABG pilot trial. Subsequent patients are now being randomized to receive either CD133(+) stem cell or placebo.


Assuntos
Antígenos CD , Ponte de Artéria Coronária , Glicoproteínas , Transplante de Células-Tronco Mesenquimais , Isquemia Miocárdica/cirurgia , Miocárdio/patologia , Peptídeos , Antígeno AC133 , Idoso , Antígenos CD/efeitos adversos , Canadá , Doença Crônica , Ponte de Artéria Coronária/métodos , Estudos de Viabilidade , Seguimentos , Glicoproteínas/efeitos adversos , Humanos , Injeções , Masculino , Transplante de Células-Tronco Mesenquimais/métodos , Pessoa de Meia-Idade , Isquemia Miocárdica/patologia , Isquemia Miocárdica/fisiopatologia , Peptídeos/efeitos adversos , Projetos Piloto , Índice de Gravidade de Doença , Volume Sistólico , Transplante Autólogo , Resultado do Tratamento
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