RESUMO
Aqueous glutathione selenium nano-incorporation (GSH-SeN-Inco) was prepared by gamma radiation in presence of microbial glutathione (GSH) and selenium dioxide. The novel prepared GSH-SeN-Inco are validated by UV-vis spectroscopy, TEM (17.5 nm), DLS, XRD, EDX and FTIR spectrum reveals the presence of GSH moiety that coating the selenium nanoparticles (SeNPs) forming GSH-SeN-Inco. The XRD analysis verified the presence of metallic SeNPs. The nucleation and radiolysis mechanism of GSH-SeN-Inco formation are also discussed. The size GSH-SeN-Inco (17.5 nm) is affected by certain factors such as concentration of GSH, selenium dioxide, and absorbed dose of gamma radiation. The present study explored the positive role of GSH-SeN-Inco as an antitumor activity against HepG-2 and MCF-7, with IC50 at a concentration of 1.00 and 0.9 mM, respectively. The GSH-SeN-Inco show significant scavenging activity at 33%. The GSH-SeN-Inco shows antimicrobial potential against Gram-negative and Gram-positive bacteria with significant MIC especially Escherichia coli ATCC 25922 at 5.20 µg/ml.
Assuntos
Antibacterianos/farmacologia , Antineoplásicos/farmacologia , Antioxidantes/farmacologia , Glutationa/farmacologia , Nanopartículas/química , Selênio/farmacologia , Antibacterianos/síntese química , Antibacterianos/química , Antineoplásicos/síntese química , Antineoplásicos/química , Antioxidantes/síntese química , Antioxidantes/química , Compostos de Bifenilo/antagonistas & inibidores , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Ensaios de Seleção de Medicamentos Antitumorais , Glutationa/química , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Positivas/efeitos dos fármacos , Humanos , Tamanho da Partícula , Picratos/antagonistas & inibidores , Selênio/químicaRESUMO
BACKGROUND: Colistin resistance is mainly driven by alterations in the Gram-negative outer membrane lipopolysaccharides and is caused, in most cases, by mutations in mgrB gene. However, the recent emergence of plasmid-encoded colistin resistance among Enterobacteriaceae strains represents a serious threat to global public health. In this paper we have investigated the rates of colistin resistance and the underlying mechanisms in 450 Klebsiella pneumoniae and Escherichia coli isolates obtained from cancer patients in Egypt. METHODS: Colistin susceptibility and minimum inhibitory concentrations were determined according to the European Committee on Antimicrobial Susceptibility Testing, by broth microdilution, and by E-test. The mcr-1, mcr-2 and mgrB genes were detected by PCR and then sequenced. Clonal diversity in colistin-resistant K. pneumoniae was evaluated by multilocus sequence typing. RESULTS: Forty (8.8%) colistin-resistant isolates, including 22 K. pneumoniae and 18 E. coli, were isolated over 18 months. Of these, 50% were carbapenem-resistant, out of which nine were blaOXA-48 and seven blaNDM-1 positive. The mechanisms of colistin resistance could be revealed only in three of the 40 resistant strains, being represented by mcr-1 in one blaNDM-1-positive E. coli strain and in one K. pneumoniae ST11 and by mgrB mutations, detected in one K. pneumoniae isolate. None of the studied isolates harbored mcr-2. CONCLUSIONS: Our results demonstrate a high frequency of colistin resistance in enterobacterial strains isolated from cancer patients, but a low prevalence of the most well known resistance mechanisms.
Assuntos
Colistina , Farmacorresistência Bacteriana/genética , Escherichia coli/genética , Klebsiella pneumoniae/genética , Neoplasias , Colistina/farmacologia , Egito , Escherichia coli/efeitos dos fármacos , Proteínas de Escherichia coli/genética , Genes Bacterianos , Humanos , Klebsiella pneumoniae/efeitos dos fármacos , Proteínas de Membrana/genética , Testes de Sensibilidade Microbiana , Tipagem de Sequências MultilocusRESUMO
In this work, the new concept of "memory dependent derivative" in the Pennes' bio-heat transfer process of skin tissues is employed to investigate the one-dimensional problem of a skin tissue under sinusoidal heat flux conditions. Laplace transform technique is utilized to solve the problem. We investigate, numerically, the bio-heat transfer equation with memory-dependent derivative to find the effect on the tissue temperature of the kernel function and the time-delay parameter which are characteristic of memory dependent derivative heat transfer. Correlations are made with the results obtained in the case of the absence of memory-dependent derivative parameters. The effects of the time-delay on the temperature distribution in skin tissue for different forms of kernel functions are examined.
Assuntos
Modelos Biológicos , Temperatura Cutânea , Condutividade Térmica , Algoritmos , Temperatura Alta , Humanos , Fatores de TempoRESUMO
Antibacterial bionanostructures were produced from cellulose nanocrystals (CNC) with immobilized lysozyme from hen egg white (HEW) and T4 bacteriophage, respectively. The nanocrystals were prepared from microcrystalline cellulose by ammonium persulfate oxidation with a yield of 68% and having an average size of 250 nm and low polydispersity index. HEW lysozyme (HEWL) and T4 lysozyme (T4L) were immobilized to CNC by different mechanisms including adsorption and covalent coupling to carbodiimide-activated carboxylate groups and to glutaraldehyde-activated aminated CNC (Am-CNC), respectively. The effect of immobilization on the enzymatic activity (both lytic and hydrolytic) and antibacterial activity of the lysozymes was studied using different methods. Am-CNC-lysozyme conjugates retained the highest lytic activity, 86.3% and 78.3% for HEWL and T4L, respectively. They also showed enhanced bactericidal activity with high potency against Gram-positive as well as Gram-negative bacteria in a relatively shorter time as compared to the free enzymes and resulted in extensive cellular damage, as shown by transmission electron microscopy. The enhanced antibacterial activity was correlated with the increase in zeta potential of Am-CNC-lysozyme conjugates. The immobilized lysozyme preparations further exhibited enhanced storage stability at 4 and 22 °C.
Assuntos
Antibacterianos/química , Celulose/análogos & derivados , Enzimas Imobilizadas/química , Muramidase/química , Nanopartículas/química , Antibacterianos/farmacologia , Bacteriófago T4/enzimologia , Estabilidade Enzimática , Enzimas Imobilizadas/farmacologia , Micrococcus/efeitos dos fármacos , Muramidase/farmacologia , Eletricidade EstáticaRESUMO
A Streptomyces strain was isolated from soil and the sequence of 1471 nucleotides of its 16S rDNA showed 99% identity to Streptomyces sp. HV10. This newly isolated Streptomyces strain produced an extracellular polysaccharide (EPS) composed mainly of glucose and mannose in a ratio of 1:4.1, as was characterized by Fourier transform infrared spectroscopy (FTIR), HPLC and ¹H-NMR. The antioxidant activities of the partially purified MOE6-EPS were determined by measuring the hydroxyl free radical scavenging activity and the scavenging of 2,2-diphenyl-2-picryl-hydrazyl (DPPH) radicals. In addition, the partially purified MOE6-EPS showed high ferrous ion (Fe2+) chelation activity which is another antioxidant activity. Interestingly, 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assays that were colorimetric assays for NAD(P)H-dependent cellular oxidoreductases and a proxy of the number of viable cells, showed that the partially purified MOE6-EPS inhibited the proliferation of the human breast cancer cells (MDA-MB-231). The scratch wound assay showed that MOE6-EPS reduced the migration of mouse breast cancer cells (4T1). This study reports the production of EPS from Streptomyces species with promising antioxidant, metal chelating and mammalian cell inhibitory activities.
Assuntos
Polissacarídeos Bacterianos/isolamento & purificação , Polissacarídeos Bacterianos/farmacologia , Streptomyces/química , Animais , Antineoplásicos/química , Antineoplásicos/isolamento & purificação , Antineoplásicos/farmacologia , Antioxidantes/química , Antioxidantes/isolamento & purificação , Antioxidantes/farmacologia , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Cromatografia Líquida de Alta Pressão , Humanos , Radical Hidroxila/antagonistas & inibidores , Radical Hidroxila/química , Quelantes de Ferro/química , Quelantes de Ferro/isolamento & purificação , Quelantes de Ferro/farmacologia , Camundongos , Filogenia , Polissacarídeos Bacterianos/química , Espectroscopia de Prótons por Ressonância Magnética , Espectrofotometria Ultravioleta , Espectroscopia de Infravermelho com Transformada de Fourier , Streptomyces/classificação , Streptomyces/genéticaRESUMO
Five bacterial isolates from honey and bee gut were selected based on their high levansucrase activity and levan yield which were strongly positively correlated. All isolates showed good tolerance to temperature up to 70 °C, to NaCl up to 3 M and to 0.1% H2O2. They maintained over 59 and 64% survival at pH 9.0 and 2.0 respectively, but showed varying tolerance to 0.1% bile salts and pancreatic enzymes. Most isolates were susceptible to widely used antibiotics, but demonstrated diverse antimicrobial activity. Non hemolytic isolates were identified on the basis of 16S rRNA sequencing as Bacillus subtilis HMNig-2 and B. subtilis MENO2 with 97% homology. They exhibited promising probiotic characteristics and achieved highest levansucrase activity of 94.1 and 81.5 U/mL respectively. Both exhibited highest biofilm formation ability in static microtiter plate assay. Also, they achieved 34 and 26% adhesion respectively to Caco-2cells and had highest free radical scavenging activity of 30.8 and 26.2% respectively. The levans of the two isolates showed good antimicrobial activity against some pathogens and exhibited positive prebiotic effect (prebiotic index >1) with Lactobacillus casei and Lactobacillus reuteri. Results suggest a correlation between levansucrase production, levan yield and pre-probiotic activities of the studied strains.
Assuntos
Bacillus/isolamento & purificação , Abelhas/microbiologia , Hexosiltransferases/metabolismo , Mel/microbiologia , Animais , Antibacterianos/farmacologia , Bacillus/efeitos dos fármacos , Bacillus/enzimologia , Bacillus/fisiologia , Aderência Bacteriana , Proteínas de Bactérias/metabolismo , Células CACO-2 , Humanos , Concentração de Íons de Hidrogênio , Testes de Sensibilidade Microbiana , Viabilidade Microbiana , Probióticos/farmacologia , RNA Bacteriano/análise , RNA Ribossômico 16S/análise , Análise de Sequência de RNA , TermotolerânciaRESUMO
BACKGROUND: Moraxella catarrhalis is an established pathogen that is causing substantial infections to both children and adults. However, so far there is no effective vaccine to halt the spread of these infections. METHODS: Immunoinformatics tools were used to predict M. catarrhalis epitopes that could offer immunoprotection among major proportions of human populations worldwide. Mice were immunized with the best 3 peptides and then challenged with M. catarrhalis in the pulmonary clearance model. Finally, antibodies against these epitopes were detected in humans. RESULTS: Immunoinformatics analyses identified 44 epitopes that are predicted to be good major histocompatibility complex class II binders and at the same time show high population coverage worldwide. After intraperitoneal immunization of mice with the best 3 peptides, peptide A, derived from lactoferrin-binding protein A, showed superior activity in immunogenicity and in clearing M. catarrhalis from mouse lungs. Higher clearance was obtained by combining intraperitoneal and intranasal immunization. In the serum samples from children with otitis media infected with M. catarrhalis, antibody levels against peptide A were significantly lower than in samples from children without otitis media. CONCLUSIONS: Peptide A is the first promising peptide-based vaccine against M. catarrhalis Immunoinformatics predicts that it should have a global protection around the world.
Assuntos
Proteínas de Bactérias/imunologia , Vacinas Bacterianas/imunologia , Proteínas de Transporte/imunologia , Moraxella catarrhalis/imunologia , Infecções por Moraxellaceae/prevenção & controle , Otite Média/imunologia , Peptídeos/imunologia , Administração Intranasal , Sequência de Aminoácidos , Animais , Anticorpos Antibacterianos/sangue , Proteínas de Bactérias/genética , Proteínas de Transporte/genética , Criança , Pré-Escolar , Biologia Computacional , Modelos Animais de Doenças , Epitopos/imunologia , Feminino , Humanos , Injeções Intraperitoneais , Pulmão/imunologia , Pulmão/microbiologia , Camundongos , Camundongos Endogâmicos BALB C , Infecções por Moraxellaceae/imunologia , Infecções por Moraxellaceae/microbiologia , Peptídeos/administração & dosagemRESUMO
The main objective of this study was to decipher the molecular mechanism of resistance to carbapenems and aminoglycosides in a large series of 150 Acinetobacter baumannii clinical isolates collected from July 2012 to September 2013 in Egypt. We report for the first time the emergence of bla(NDM-1) and the cooccurrence of 16S rRNA methylase armA with bla(NDM-1) and bla(OXA-23) in Egyptian hospitals. Multilocus sequence typing identified 27 distinct sequence types, 11 of which were novel.
Assuntos
Acinetobacter baumannii/genética , RNA Ribossômico 16S/genética , beta-Lactamases/genética , Egito , Metiltransferases/genética , Tipagem de Sequências MultilocusRESUMO
Acinetobacter baumannii is one of the most significant threats to global public health. This threat is compounded by the fact that A. baumannii is rapidly becoming resistant to all relevant antimicrobials. Identifying key microbial factors through which A. baumannii resists hostile host environment is paramount to the development of novel antimicrobials targeting infections caused by this emerging pathogen. An attractive target could be a molecule that plays a role in the pathogenesis and stress response of A. baumannii. Accordingly, the universal stress protein A (UspA) was chosen to be fully investigated in this study. A platform of A. baumannii constructs, expressing various levels of the uspA gene ranging from zero to thirteen folds of wild-type level, and a recombinant E. coli strain, were employed to investigate the role of UspA in vitro stress and in vivo pathogenesis. The UspA protein plays a significant role in protecting A. baumannii from H(2)O(2), low pH, and the respiratory toxin 2,4-DNP. A. baumannii UspA protein plays an essential role in two of the deadliest types of infection caused by A. baumannii; pneumonia and sepsis. This distinguishes A. baumannii UspA from its closely related homolog, the Staphylococcus aureus Usp2, as well as from the less similar Burkholderia glumae Usps. Heterologous and overexpression experiments suggest that UspA mediates its role via an indirect mechanism. Our study highlights the role of UspA as an important contributor to the A. baumannii stress and virulence machineries, and polishes it as a plausible target for new therapeutics.
Assuntos
Acinetobacter baumannii/fisiologia , Proteínas de Bactérias/metabolismo , Proteínas de Choque Térmico/metabolismo , Pneumonia Bacteriana/patologia , Sepse/microbiologia , Sepse/patologia , Estresse Fisiológico , Fatores de Virulência/metabolismo , Animais , Modelos Animais de Doenças , Feminino , Camundongos Endogâmicos C57BL , Pneumonia Bacteriana/microbiologia , VirulênciaRESUMO
Bacteria in the genus Streptomyces and its close relatives are prolific producers of secondary metabolites with antibiotic activity. Genome sequencing of these bacteria has revealed a rich source of potentially new antibiotic pathways, whose products have never been observed. Moreover, these new pathways can provide novel genes that could be used in combinatorial biosynthesis approaches to generate unnatural analogues of existing antibiotics. We explore here the use of multiple orthologous integrating plasmid systems, based on the int/attP loci from phages TG1, SV1, and ÏBT1, to express the polyketide synthase (PKS) for erythromycin in a heterologous Streptomyces host. Streptomyces strains containing the three polyketide synthase genes eryAI, eryAII, and eryAIII expressed from three different integrated plasmids produced the aglycone intermediate, 6-deoxyerythronolide B (6-dEB). A further pair of integrating plasmids, both derived from the ÏC31 int/attP locus, were constructed carrying a gene cassette for glycosylation of the aglycone intermediates, with or without the tailoring gene, eryF, required for the synthesis of erythronolide B (EB). Liquid chromatography-mass spectrometry of the metabolites indicated the production of angolosaminyl-6-dEB and angolosaminyl-EB. The advantages of using multiplexed integrating plasmids for engineering expression and for combinatorial biosynthesis were demonstrated.
Assuntos
Antibacterianos/biossíntese , Proteínas de Bactérias/genética , Eritromicina/metabolismo , Plasmídeos/genética , Streptomyces/metabolismo , Proteínas de Bactérias/biossíntese , Cromatografia Líquida , Eritromicina/análogos & derivados , Eritromicina/biossíntese , Engenharia Genética , Glicosilação , Espectrometria de Massas , Complexos Multienzimáticos/metabolismo , Família Multigênica/genética , Streptomyces/genéticaRESUMO
BACKGROUND: Pseudomonas aeruginosa is an important nosocomial pathogen, commonly causing infections in immunocompromised patients. The aim of this study was to examine the genetic relatedness of metallo-beta-lactamase (MBL) producing carbapenem resistant Pseudomonas aeruginosa clinical isolates collected from 2 tertiary hospitals in Cairo, Egypt using Multi Locus sequence typing (MLST). METHODS: Phenotypic and genotypic detection of metallo-beta-lactamase for forty eight non-duplicate carbapenem resistant P. aeruginosa isolates were carried out. DNA sequencing and MLST were done. RESULTS: The bla VIM-2 gene was highly prevalent (28/33 strains, 85%) among 33 MBL-positive P.aeruginosa isolates. MLST revealed eleven distinct Sequence Types (STs). A unique ST233 clone producing VIM-2 was documented by MLST in P.aeruginosa strains isolated from Cairo university hospitals. The high prevalence of VIM-2 producers was not due to the spread of a single clone. CONCLUSIONS: The findings of the present study clearly demonstrate that clones of VIM-2 positive in our hospitals are different from those reported from European studies. Prevalence of VIM-2 producers of the same clone was detected from surgical specimens whereas oncology related specimens were showing diverse clones.
Assuntos
Infecções por Pseudomonas/epidemiologia , Pseudomonas aeruginosa/genética , beta-Lactamases/genética , Carbapenêmicos , Infecção Hospitalar/epidemiologia , Egito , Genótipo , Humanos , Testes de Sensibilidade Microbiana , Epidemiologia Molecular , Tipagem de Sequências Multilocus , Infecções por Pseudomonas/microbiologia , Pseudomonas aeruginosa/isolamento & purificação , Análise de Sequência de DNA , Centros de Atenção Terciária , Resistência beta-Lactâmica/genéticaRESUMO
Mycoplasmas are fastidious slow growing organisms lacking a cell wall and mostly isolated from the mucosal surfaces of the respiratory and genitourinary tracts. There is a dearth of information regarding clinical Mycoplasma spp. isolates among Egyptian patients. A total of 170 samples were collected from patients and apparently healthy personnel in local public hospitals in Cairo, Egypt. Isolation of Mycoplasma spp. was carried out using appropriate culture media and further identification was carried out by biochemical tests followed by serotyping using specific antisera. Confirmation was done by PCR for detection of different Mycoplasma spp. using genus-specific primers targeting 16S ribosomal RNA gene. Characterization of the antibiotic resistance and sensitivity pattern against different antimicrobials was carried out using disc diffusion test. The results indicated the presence of six Mycoplasma spp. in 22.94% of the samples. Mycoplasmas were detected more frequently in throat swabs than sputum. Mycoplasma pneumoniae was highly sensitive to macrolides and quinolones but less sensitive to aminoglycosides and tetracyclines. Molecular techniques were found to be of more rapid, highly sensitive, able to detect nonviable organisms, and cost effective. These results shed light on difficulties of Mycoplasma detection and the superiority of molecular techniques over culture.
Assuntos
Técnicas de Tipagem Bacteriana/métodos , Hospitais , Tipagem Molecular/métodos , Mycoplasma/classificação , Mycoplasma/isolamento & purificação , Contagem de Colônia Microbiana , Egito , Humanos , Dados de Sequência Molecular , Mycoplasma/crescimento & desenvolvimentoRESUMO
We analyzed highly pathogenic avian influenza A(H5N1) viruses isolated from humans infected in Egypt during 2007-2011. All analyzed viruses evolved from the lineage of subtype H5N1 viruses introduced into Egypt in 2006; we found minimal evidence of reassortment and no exotic introductions. The hemagglutinin genes of the viruses from 2011 formed a monophyletic group within clade 2.2.1 that also included human viruses from 2009 and 2010 and contemporary viruses from poultry; this finding is consistent with zoonotic transmission. Although molecular markers suggestive of decreased susceptibility to antiviral drugs were detected sporadically in the neuraminidase and matrix 2 proteins, functional neuraminidase inhibition assays did not identify resistant viruses. No other mutations suggesting a change in the threat to public health were detected in the viral proteomes. However, a comparison of representative subtype H5N1 viruses from 2011 with older subtype H5N1 viruses from Egypt revealed substantial antigenic drift.
Assuntos
Antígenos Virais/imunologia , Galinhas/virologia , Genes Virais , Virus da Influenza A Subtipo H5N1/genética , Virus da Influenza A Subtipo H5N1/patogenicidade , Influenza Humana/virologia , Doenças das Aves Domésticas/virologia , Animais , Egito/epidemiologia , Ensaios Enzimáticos , Evolução Molecular , Deriva Genética , Glicoproteínas de Hemaglutininação de Vírus da Influenza/classificação , Glicoproteínas de Hemaglutininação de Vírus da Influenza/genética , Humanos , Virus da Influenza A Subtipo H5N1/classificação , Virus da Influenza A Subtipo H5N1/imunologia , Influenza Humana/epidemiologia , Neuraminidase/genética , Filogenia , Doenças das Aves Domésticas/epidemiologiaRESUMO
BACKGROUND: During October 2010, Egypt reported an outbreak of acute hemorrhagic conjunctivitis (AHC). A total of 1831 cases were reported from three governorates; 1703 cases in El Daqahliya, 92 cases in Port Said, and 36 in Damietta. The purpose of this study was to identify and characterize the causative agent associated with this outbreak. METHODS: The U.S. Naval Medical Research Unit No.3 (NAMRU-3) was contacted by the Egyptian Ministry of Health and Population to perform diagnostic laboratory testing on eighteen conjunctival swabs from patients with conjunctivitis from El Daqahliya Governorate. Conjunctival swabs were tested by molecular methods for human adenovirus (HAdV) and enteroviruses (EV). Virus isolation was performed; the isolated virus was further characterized by molecular typing and phylogenetic analysis. RESULTS: The majority of the samples (17/18) were positive for enterovirus and all were negative for HAdV. Molecular typing and sequencing of the isolated virus revealed the presence of coxsackievirus A24 variant. Phylogenetic analysis based on the VP1 and 3C regions demonstrated that the Egyptian viruses belonged to Genotype IV and are closely related to coxsackievirus A24 variant, reported in a similar outbreak in China in August 2010. CONCLUSIONS: This study strongly suggests that coxsackievirus A24 variant was associated with the acute hemorrhagic conjunctivitis outbreak reported in Egypt in October 2010. There is a possibility that the same strain of CV-A24v was implicated in the AHC outbreaks in both China and Egypt in 2010.
Assuntos
Conjuntivite Hemorrágica Aguda/epidemiologia , Conjuntivite Hemorrágica Aguda/virologia , Enterovirus/isolamento & purificação , Adenovírus Humanos/genética , Adenovírus Humanos/isolamento & purificação , Surtos de Doenças , Egito/epidemiologia , Enterovirus/classificação , Enterovirus/genética , Feminino , Genótipo , Humanos , Dados de Sequência Molecular , Tipagem Molecular/métodos , FilogeniaRESUMO
Background: The Egyptian healthcare system is currently in the early phase of health technology assessment (HTA) implementation. The aim of this study is to propose an implementation roadmap based on the national healthcare system status. Methods: A survey was conducted among Egyptian healthcare sector decision-makers to assess the current and future (preferred) HTA implementation status in Egypt based on a widely used international scorecard methodology. Subsequently, interviews were conducted with experts representing middle- and top-tier management in the Egyptian healthcare system to interpret the survey results and recommend specific actions. Results: Experts recommended more capacity-building programs for HTA and health economics. Additionally, they proposed establishing HTA units in separate healthcare authorities and merging them into a single central HTA unit in the long term. Regarding the scope of implementation, experts recommended commencing with the assessment of innovative pharmaceuticals, and thereafter, expanding the scope to cover all health technologies in the long term. Additionally, they recommended using innovative tools such as "multi-criteria decision analysis (MCDA)" for tendering, and "managed entry agreements" for reimbursement decisions. Local burden of diseases and costing studies were also recommended to facilitate the implementation of HTA. Conclusion: Experts agreed that several actions are required for successful HTA implementation in Egypt, including coordination between HTA bodies, application of an explicit MCDA framework, and strengthening of local evidence generation. To implement these actions, investment in technical capacity-building is indispensable. Most experts favored using multiple and soft cost-effectiveness thresholds. Efforts should be made to publish HTA submission guidelines and timelines of the processes.
Assuntos
Fortalecimento Institucional , Avaliação da Tecnologia Biomédica , Avaliação da Tecnologia Biomédica/métodos , Egito , Inquéritos e Questionários , Atenção à SaúdeRESUMO
Serratia marcescens is a Gram-negative bacterium with both environmental and host-associated strains. Pigmentation is reportedly inversely correlated with infection frequency, and prodigiosin is one of Serratia pigments that has medical and industrial applications. Here, we report the draft genome sequence of prodigiosin-hyperproducing Serratia marcescens strain N2, isolated from Cairo, Egypt. The sequence is assembled into 142 contigs, with a combined size of 5,570,793 bp. The assembled genome carries typical S. marcescens genes, with potential prodigiosin-biosynthesizing genes detected.
Assuntos
Prodigiosina , Serratia marcescens , Egito , Pigmentação , Serratia marcescens/genéticaRESUMO
BACKGROUND: Current worldwide pandemic coronavirus disease 2019 (COVID-19) with high numbers of mortality rates and huge economic problems require an urgent demand for safe and effective vaccine development. Inactivated SARS-CoV2 vaccine with alum. Hydroxide can play an important role in reducing the impacts of the COVID-19 pandemic. In this study, vaccine efficacy was evaluated through the detection of the neutralizing antibodies that protect mice from challenge with SARS-CoV 2 3 weeks after the second dose. We conclude that the vaccine described here has safety and desirable properties, and our data support further development and plans for clinical trials. METHODS: Characterized SARS-COV-2 strain, severe acute respiratory syndrome coronavirus 2 isolates (SARS-CoV-2/human/EGY/Egy-SERVAC/2020) with accession numbers; MT981440; MT981439; MT981441; MT974071; MT974069; and MW250352 at GenBank were isolated from Egyptian patients SARS-CoV-2-positive. Development of inactivated vaccine was carried out in a BSL-3 facilities and the immunogenicity was determined in mice at two doses (55 and 100 µg per dose). RESULTS: The distinct cytopathic effect induced by SARS-COV-2 propagation on Vero cell monolayers and the viral particles were identified as Coronaviridae by transmission electron microscopy and RT-PCR on infected cells cultures. Immunogenicity of the developed vaccine indicated the high antigen-binding and neutralizing antibody titers, regardless of the dose concentration, with excellent safety profiles and no deaths or clinical symptoms in mice groups. The efficacy of the inactivated vaccine formulation was tested by the wild virus challenge of the vaccinated mice and viral replication detection in lung tissues. CONCLUSIONS: Vaccinated mice recorded complete protection from challenge infection via inhibition of SARS-COV-2 replication in the lung tissues of mice following virus challenge, regardless of the level of serum neutralizing antibodies. This finding will support future trials for the evaluation of an applicable SARS-CoV-2 vaccine candidate.
RESUMO
Nosocomial infections caused by enterococci are an ongoing global threat. Thus, finding therapeutic agents for the treatment of such infections are crucial. Some Enterococcus faecalis strains are able to produce antimicrobial peptides called bacteriocins. We analyzed 65 E. faecalis isolates from 43 food samples and 22 clinical samples in Egypt for 17 common bacteriocin-encoding genes of Enterococcus spp. These genes were absent in 11 isolates that showed antimicrobial activity putatively due to bacteriocins (three from food, including isolate OS13, and eight from clinical isolates). The food-isolated E. faecalis OS13 produced bacteriocin-like inhibitory substances (BLIS) named enterocin OS13, which comprised two peptides (enterocin OS13α OS13ß) that inhibited the growth of antibiotic-resistant nosocomial E. faecalis and E. faecium isolates. The molecular weights of enterocin OS13α and OS13ß were determined as 8079 Da and 7859 Da, respectively, and both were heat-labile. Enterocin OS13α was sensitive to proteinase K, while enterocin OS13ß was resistant. Characterization of E. faecalis OS13 isolate revealed that it belonged to sequence type 116. It was non-hemolytic, bile salt hydrolase-negative, gelatinase-positive, and sensitive to ampicillin, penicillin, vancomycin, erythromycin, kanamycin, and gentamicin. In conclusion, BLIS as enterocin OS13α and OS13ß represent antimicrobial agents with activities against antibiotic-resistant enterococcal isolates.
Assuntos
Bacteriocinas/farmacologia , Infecção Hospitalar/tratamento farmacológico , Farmacorresistência Bacteriana/efeitos dos fármacos , Enterococcus faecalis/química , Bacteriocinas/química , Bacteriocinas/isolamento & purificação , Infecção Hospitalar/microbiologia , Farmacorresistência Bacteriana/genética , Egito , Enterococcus faecalis/efeitos dos fármacos , Enterococcus faecalis/genética , Enterococcus faecalis/patogenicidade , Enterococcus faecium/efeitos dos fármacos , Enterococcus faecium/patogenicidade , Microbiologia de Alimentos , Humanos , Testes de Sensibilidade MicrobianaRESUMO
Purpose: A novel coronavirus (COVID-19) that has not been previously identified in humans and has no specific treatment has recently spread. Treatment trials using antiviral and immune-modulating drugs such as hydroxychloroquine (HCQ) were used to control this viral outbreak however several side effects have emerged. Berberine (BER) is an alkaloid that has been reported to reveal some pharmacological properties including antioxidant and antimicrobial activities. Additionally, Zinc oxide nanoparticles (ZnO-NPs) possess potent antioxidant and anti-inflammatory properties. Therefore, this study was undertaken to estimate the efficiency of both BER and synthetic ZnO/BER complex as an anti-COVID-19 therapy. Methods: First, the ZnO/BER complex was prepared by the facile mixing method. Then in vitro studies on the two compounds were conducted including VeroE6 toxicity, anti-COVID-19 activity, determination of inhibitory activity towards papain-like proteinase (PL pro) and spike protein- and receptor- binding domain (RBD) as well as assessment of drug toxicity on RBCs. Results: The results showed that ZnO/BER complex acts as an anti-COVID-19 by inhibiting spike protein binding with angiotensin-converting enzyme II (ACE II), PL pro activity, spike protein and E protein levels, and expression of both E-gene and RNA dependent RNA polymerase (RdRp) at a concentration lower than that of BER or ZnO-NPs alone. Furthermore, ZnO/BER complex had antioxidant and antimicrobial properties where it prevents the auto oxidation of 2,2-Diphenyl-1-picrylhydrazyl (DPPH) and the culture of lower respiratory system bacteria that affected Covid 19 patients. The ZnO/BER complex prevented as well the HCQ cytotoxic effect on both RBC and WBC (in vitro) and hepatotoxicity, nephrotoxicity and anemia that occurred after HCQ long administration in vivo. Conclusion: The ZnO/BER complex can be accounted as promising anti-COVID 19 candidate because it inhibited the virus entry, replication, and assembly. Furthermore, it could be used to treat a second bacterial infection that took place in hospitalized COVID 19 patients. Moreover, ZnO/BER complex was found to eliminate the toxicity of long-term administration of HCQ in vivo.