Genetic Engineering and Biotechnology Center

Havana, Cuba

Genetic Engineering and Biotechnology Center

Havana, Cuba
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Tamayo B.A.,Genetic Engineering and Biotechnology Center | Geada L.D.,University of Habana | Fernandez E.G.N.,University of Sao Paulo | Dorta E.L.,Genetic Engineering and Biotechnology Center | And 12 more authors.
Latin American Journal of Pharmacy | Year: 2013

Cuban hepatitis B vaccine active pharmaceutical ingredient was purified by immunoaffinity chromatography using CB.Hep-1 monoclonal antibody (mAb). The main mAb purification process step was an affinity chromatography. However, the affinity chromatography matrix stability has not been demonstrated under specific experimental conditions, which is mandatory for vaccine production. Therefore, in this research, mAb recovery, mAb purity, ligand leakage, and mouse DNA content were studied for more than 100 purification cycles using two independent Protein A-Sepharose (PAS) matrices and mouse ascites as complex biological source of mAb. As results, matrices showed a mAb recovery of 64.7 ± 15.5% and 78.1 ± 11.1%, respectively (p = 0.6974). The high mAb purity (> 90%), and the extremely low content of Staphylococcal Protein A (< 7.0 ppm) and mouse DNA (< 6.0 pg/mg) detected in PAS elution fractions throughout 133 purification cycle supports the matrix stability under specific experimental conditions and does not compromise the application of CB.Hep-1 for vaccine production.

Alvarez M.T.,Genetic Engineering and Biotechnology Center | Ferro V.W.,Genetic Engineering and Biotechnology Center | Geada L.D.,University of Habana | Medina S.Y.,Genetic Engineering and Biotechnology Center | And 5 more authors.
Latin American Journal of Pharmacy | Year: 2013

The presence of an immunologically-relevant epitope comprised between amino acids 134 and 153 of Heberbiovac® HB vaccine active pharmaceutical ingredient (API) using an enzyme-linked immunosorbent assay (ELISA) based on CB.Hep-4 monoclonal antibody (mAb) was investigated in this study. To reach this main subject, the validation of CB.Hep-4 mAb quantification system was firstly performed. The previously established ELISA to quantify CB.Hep-4 mAb was characterized by short incubation times at high temperature, which is unusual because of poor protein stability under these conditions. The linear range and recovery ranged 3.1-50 ng/mL and 95.2-105.3%, respectively. Maximum intra-and inter-assay variation coefficients were 6.5 and 7.0%, respectively. Thus, CB.Hep-4 mAb was quantified with specificity, precision, accuracy, and without interferences with this immunoassay. Then, several consecutive samples of Heberbiovac® HB API were monitored with CB.Hep-4 mAb, to demonstrate the presence of an immunologically-relevant epitope in this recombinant protein for vaccination.

Abreu O.,University of Camagüey | Sanchez I.,Genetic Engineering and Biotechnology Center | Barreto G.,University of Camagüey | Campal A.,Genetic Engineering and Biotechnology Center
Journal of Pharmaceutical Negative Results | Year: 2017

Background: Plant Kingdom still constitutes a source for antimicrobials, screening bioassays of plants extracts is one of the first steps in the search of new antimicrobial compounds. Cuba has a rich flora with a high degree of endemism that practically has not been investigated. Method: Twelve acetone extracts (1mg/ml) of seven Cuban plants (four endemic), were tested by agar disc diffusion method against selected strains of bacteria and fungi: Escherichia coli (three strains), Staphylococcus aureus and Candida albicans. Results: In general null or poor antimicrobial effect was observed, except in Caesalpinia bahamensis subs bahamensis heartwood, that showed activity of interest against bacteria even at 0,5mg/ml; while modest antibacterial effects was found in endemics: Hypericum styphelioides (leave, stem), H. limosum (leave, stem), Vaccinium leonis (leave) and V. ramonii (leave, stem); Agdestis clematidea show lowest effect. S. aureus was the most sensitive bacteria (six species and 11 extracts) and only a negligible activity was found against C. albicans in four extract of four species. Discussion: Morphology of Gram positive bacteria, in contrast to Gram negative that have a more resistant outer membrane, seem to be the cause of S. aureus sensitiveness. Starting from these results, further current antimicrobial research approach related virulence factors mechanisms interference can be carried out in these plants. Conclusions: In this experimental conditions, except in one specie, null or poor antimicrobial effect was found in tested plants, studies on these plants have to be continues, since in other conditions maybe could be found some bacteriostatic or bactericide activity. © 2017 Journal of Pharmaceutical Negative Results | Published by Wolters Kluwer - Medknow.

Acosta Medina E.,University of Habana | Delgado Roche L.,University of Habana | de los Becquer M.A.,University of Habana | Falcon Cama V.,Genetic Engineering and Biotechnology Center | And 2 more authors.
Acta Microscopica | Year: 2012

Atherosclerosis is a disease of the vascular wall that leads to myocardial infarction, stroke, ischemia, gangrene and aneurysm. The primary lesion of atherosclerosis is an elevated focal plaque within the intima, with a central lipid core (mainly cholesterol and cholesterol esters) and a fibrous layer that covers it. The aim of this study was the histopathological and ultrastructural characterization of the atherosclerotic lesions induced in rabbits by the administration of Lipofundin 20%, a rich-lipid emulsion. Nineteen New Zealand rabbits were distributed in two groups. Group A (8 animals) only received intravenous injections of PBS and Group B (11 animals) received 2 mL / kg weight of Lipofundin 20% for 8 days. On day 9 animals were sacrificed and the aortic archs were isolated for histological and ultrastructural examination. In Group A, non-histopathology alterations were observed in the artery intima. However, all aorta samples from rabbits of Group B (treated with Lipofundin 20%) showed atherosclerotic lesions characterized by intima thickening, media-to-intima migration of vascular smooth muscle cells and an increased presence of proteoglycan and collagen fibers. In some samples the injured area was thicker than media layer. Ultrastructural analysis presence of large amounts of foam cells with lipid droplets at the intracellular level and abundant extracellular lipid droplets. These lesions were classified as Type III/ IV according to the classification of the Committee on Vascular Lesions of the American Heart Association.

Medell M.,Hermanos Ameijeiras Hospital | Martinez A.,Pediatric Hospital Juan Manuel Marquez | Valdes R.,Genetic Engineering and Biotechnology Center
Brazilian Journal of Infectious Diseases | Year: 2012

Objective: Thisobservational study described the characterization of bacteria isolated from the lower respiratory tract of ventilated patients hospitalized in intensive care units. The demonstration of isolated microorganism resistance to antibiotics and a time-trend analysis of infection comparing a 48-month period were also other objectives. Method: Semi-quantitative assays of 1254 samples taken from 741 ventilated patients were performed, while pathogens were identified using the Enterotube II assay and VITEK 2 Compact equipment. Bacterial resistance to antibiotics was assessed by the Kirby-Bauer disc diffusion method and time-trend analysis of infection was based on data recorded by hospital microbiology laboratories. Results: The most prevalent isolated bacteria from the patient's lower respiratory tract were with Gram-negative bacteria (67.8%) mostly represented by: Acinetobacter spp. (25.2%), Pseudomonas spp. (18.3%) and Klebsiellas spp. (9.4%). Acinetobacter spp. showed moderate high to very high resistance to ceftriaxone (CRO), gentamicin (CN), amikacin (AK), meropenem (MRP), aztreonam (ATM) and piperacillin/tazobactam (TZP). Some isolates of Acinetobacter spp. resistant to colistin (CS) were identified in this patient population. Pseudomonas spp. and Klebsiella spp. were very highly resistant to ampicillin/sublactam (AMS) and with moderate or low resistance to CRO, ATM, MRP, AK, CN and TZP. A decrease in the Pseudomonas spp. prevalence rate was observed, whereas an increase in Acinetobacter spp. and Klebsiella spp. prevalence rates were observed in a 48-month period. Conclusion: This research corroborated that these nosocomial infections are a relevant medical problem in our context. The most prevalent bacterial infections in the lower respiratory tract of ventilated patients were by Acinetobacter spp., Pseudomonas spp. and Klebsiella spp. The panel of antibiotics used as preventive therapy was not the solution of infections and probably induced drug-resistance mechanisms in these isolated microorganisms. © 2012 Elsevier Editora Ltda.

Medell M.,Hermanos Ameijeiras Clinical Surgical Teaching Hospital HHA | Hart M.,Hermanos Ameijeiras Clinical Surgical Teaching Hospital HHA | Duquesne A.,Institute of Tropical Medicine | Espinosa F.,Hermanos Ameijeiras Clinical Surgical Teaching Hospital HHA | Valdes R.,Genetic Engineering and Biotechnology Center
MEDICC Review | Year: 2013

INTRODUCTION Nosocomial pneumonia associated with use of mechanical ventilators is one of the greatest challenges confronted by intensivists worldwide. The literature associates several bacteria with this type of infection; most common in intensive care units are Acinetobacter baumannii, Pseudomonas aeruginosa, methicillin-resistant Staphylococcus aureus and some of the Enterobacteriaceae family. OBJECTIVES To identify the causal agents of nosocomial ventilatorassociated pneumonia in patients receiving mechanical ventilation in the intensive care units of Havana's Hermanos Ameijeiras Clinical-Surgical Teaching Hospital in 2011, and to characterize their antibiotic resistance. METHODS A cross-sectional descriptive study was conducted using hospital administrative data of quantitative cultures from positive tracheal aspirates for January through December, 2011. Records were analyzed from 77 intensive care unit patients who developed nosocomial ventilator-associated pneumonia. Variables examined were age and sex, and pathogens identified from culture of tracheal aspirate and related antibiotic susceptibility. RESULTS Species most frequently isolated were: Acinetobacter baumannii in 53 patients (68.8%), Pseudomonas aeruginosa in 34 patients (44.2%), other species of Pseudomonas in 15 patients (19.5%), and Serratia marcescens, Klebsiella pneumoniae, and Escherichia coli in 12 patients each (15.6%). Some patients presented more than one pathogen in concurrent or successive infections. Antimicrobial susceptibility testing found high percentages of resistance to antibiotics in all these pathogens. Least resistance was found to colistin. CONCLUSIONS The prevalence of antibiotic resistance in bacteria causing nosocomial ventilator-associated pneumonia is of concern. Colistin is the drug of choice among the antibiotics reviewed, but sensitivity to other antibiotics should be assessed to search for more appropriate broad-spectrum antibiotics for treating nosocomial ventilator-associated pneumonia. Our results also suggest the need to strengthen infection control efforts, particularly in intensive care units, and to reassess compliance with quality control procedures. Multidisciplinary research involving microbiologists, epidemiologists, internists and intensivists is needed to fully understand the etiological and resistance patterns observed.

Medell M.,Hermanos Ameijeiras Hospital | Hart M.,Hermanos Ameijeiras Hospital | Marrero O.,Hermanos Ameijeiras Hospital | Espinosa F.,Hermanos Ameijeiras Hospital | And 2 more authors.
Brazilian Journal of Infectious Diseases | Year: 2012

Objective: To characterize mechanical ventilation-associated pneumonia (MVAP). Method: This is an observational descriptive study to characterize MVAP in 61 ventilated patients admitted in the intensive care units of the Hermanos Ameijeiras hospital during 2011. This study also aimed to isolate the bacteria causing MVAP and characterize their resistance to antibiotics. Results: 51 (83.60%) patients presented pulmonary infiltrates and 35 (50.81%) presented a clinical score ≥ 6 according to the Clinical Pulmonary Infection Score. Acinetobacter baumannii and Pseudomonas aeruginosa were the most frequently isolated microorganisms from patients with MVAP. Both microorganisms showed a high resistance to antibiotics. Carbapenems were the most frequent used antimicrobial therapeutic agents; elective antibiotic combinations were directed against both bacterial wall structure and nucleic acid synthesis. Conclusion: Patients with MVAP identified during the studied period showed similar frequency to those reported in medical literature. Thus, this study corroborated that this is still a relevant medical problem in this hospital. Acinetobacter baumannii and Pseudomonas aeruginosa were the most frequently isolated microorganisms from patients with MVAP. Antimicrobial treatment, empirical or not, are still the main risk factors for the development of multidrug-resistant strains of bacteria. The rate of resistance to antibiotics of Acinetobacter baumannii and Pseudomonas aeruginosa strains isolated from patients with MVAP was higher than those isolated from infected patients without MAVP. Tigecycline and colistin were the only antibiotics fully effective against Acinetobacter baumannii strains isolated in 2011 from patients with MVAP; against Pseudomonas aeruginosa strains, only colistin was fully effective. © 2012 Elsevier Editora Ltda.

Padilla S.,Genetic Engineering and Biotechnology Center | Alvarez T.,Genetic Engineering and Biotechnology Center | Ferro W.,Genetic Engineering and Biotechnology Center | Guevara Y.,Genetic Engineering and Biotechnology Center | And 9 more authors.
Chromatographia | Year: 2010

Several plant-derived antibody (plantibody) purification approaches have been assessed demonstrating high purification capacities, but low recoveries (<30%) and poor sorbent stability. Thus, application of sorbents with high recovery, low ligand leakage and stable under harsh sanitization conditions could improve the efficiency antibody purification from this source. This paper reports for the first time MAbsorbents assessments in plantibody purification from tobacco plants. In conclusion MAbsorbent A1P is not suitable for plantibody HB-01 purification, while MAbsorbent A2P demonstrated high recovery (37.54 ± 15.15%) in 25 purification cycles. As recommendation, we consider that other elution conditions should be assessed before restudy the stability of this sorbent. © 2010 Vieweg+Teubner Verlag | Springer Fachmedien Wiesbaden GmbH.

PubMed | Genetic Engineering and Biotechnology Center
Type: Journal Article | Journal: Plant cell reports | Year: 2013

We describe an efficient procedure for genetic transformation of commercial sugarcane varieties POJ 2878 and Ja 60-5. The transformation protocol is based on electroporation of a plasmid conferring GUS activity into cell clusters isolated from embryogenic calli. Six to eight weeks after electroporation, Ja 60-5 plants regenerated from electroporated tissues were tested and confirmed to be transgenic using histochemical glucuronidase and Southern hybridization analysis. Electroporation of intact cells is an efficient and reproducible method for sugarcane transformation and may also be useful for transformation of other plants.

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