Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 12 de 12
Filtrar
Mais filtros











Base de dados
Intervalo de ano de publicação
1.
Arch Iran Med ; 27(2): 62-71, 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-38619029

RESUMO

BACKGROUND: Non-small cell lung cancer (NSCLC) patients with COVID-19 have an excessive chance of morbidity and mortality. The fecal-nasopharyngeal microbiota compositions of NSCLC patients were assessed in this study. METHODS: In total, 234 samples were collected from 17 NSCLC patients infected with COVID-19, 20 NSCLC patients without confirmed COVID-19, 40 non NSCLC patients with COVID-19, and 40 healthy individuals. RESULTS: In lung microbiota, the abundance of Streptococcus spp. in NSCLC patients with confirmed COVID-19 was significantly higher than the two control groups. Pseudomonas aeruginosa and Staphylococcus aureus were listed as the most frequent pulmonary bacterial groups that colonized COVID-19 patients. In fecal specimens, the numbers of Bacteroidetes, Firmicutes, and Actinobacteria phyla were significantly higher amongst NSCLC patients with COVID-19. NSCLC patients infected with COVID-19 showed lower levels of Lactobacillus spp., Akkermansia muciniphila, and Bifidobacterium spp. The counts of Streptococcus spp., in NSCLC patients with COVID-19 were significantly higher than those of healthy individuals (8.49±0.70 log CFU/g wet feces vs 8.49±0.70 log CFU/g wet feces). Prevotella spp. were enriched in the gut and respiratory tracts of COVID-19 patient groups. The unbiased analysis showed an increment in Enterococcus spp., Streptococcus spp., and Prevotella spp. CONCLUSION: Eventually, it was found that compared to control groups, COVID-19 patients with NSCLC showed diminished gut bacteria diversity and increase in Lactobacillus spp., A. muciniphila, and Bifidobacterium spp. The overgrowth of Enterococcus spp., Streptococcus spp., and Prevotella spp. could be potential predictive biomarkers in the gut-lung axis of NSCLC patients with COVID-19.


Assuntos
COVID-19 , Carcinoma Pulmonar de Células não Pequenas , Coinfecção , Neoplasias Pulmonares , Microbiota , Humanos , Pulmão
2.
Exp Parasitol ; 239: 108295, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35709889

RESUMO

Visceral leishmaniasis (VL) remains a major public health problem across 98 countries. To date, VL has no effective drug. Vaccines, as the most successful breakthroughs in medicine, can promise an effective strategy to fight various diseases. More recently, self-assembled peptide nanoparticles (SAPNs) have attracted considerable attention in the field of vaccine design due to their multivalency. In this study, a SAPN nanovaccine was designed using various immunoinformatics methods. High-ranked epitopes were chosen from a number of antigens, including Leishmania-specific hypothetical protein (LiHy), Leishmania-specific antigenic protein (LSAP), histone H1, and sterol 24-c-methyltransferase (SMT). To facilitate the oligomerization process, pentameric and trimeric coiled-coil domains were employed. RpfE, a resuscitation-promoting factor of Mycobacterium tuberculosis, was added to induce strong immune responses. Pentameric and trimeric coiled-coil domains as well as eight immunodominant epitopes from antigenic proteins of Leishmania infantum, the causative agent of VL, were joined together using appropriate linkers. High-quality 3D structure of monomeric and oligomeric structures followed by refinement and validation processes demonstrated that the designed nanovaccine could be considered to be a promising medication against the parasite; however, experimental validation is essential to confirm the effectiveness of the nanovaccine.


Assuntos
Leishmania infantum , Leishmaniose Visceral , Antígenos de Protozoários , Epitopos , Humanos , Leishmaniose Visceral/parasitologia , Peptídeos , Vacinologia
3.
Recent Pat Biotechnol ; 15(4): 286-301, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34515017

RESUMO

BACKGROUND: L-Methioninase (EC 4.4.1.11; MGL) is a pyridoxal phosphate (PLP)-dependent enzyme that is produced by a variety of bacteria, fungi, and plants. L-methioninase, especially from Pseudomonas and Citrobacter sp., is considered as the efficient therapeutic enzyme, particularly in cancers such as glioblastomas, medulloblastoma, and neuroblastoma that are more sensitive to methionine starvation. OBJECTIVE: The low stability is one of the main drawbacks of the enzyme; in this regard, in the current study, different features of the enzyme, including phylogenetic, functional, and structural from Pseudomonas, Escherichia, Clostridium, and Citrobacter strains were evaluated to find the best bacterial L-Methioninase. METHODS: After the initial screening of L-Methioninase sequences from the above-mentioned bacterial strains, the three-dimensional structures of enzymes from Escherichia fergusonii, Pseudomonas fluorescens, and Clostridium homopropionicum were determined through homology modeling via GalaxyTBM server and refined by GalaxyRefine server. RESULTS AND CONCLUSION: Afterwards, PROCHECK, verify 3D, and ERRAT servers were used for verification of the obtained models. Moreover, antigenicity, allergenicity, and physico-chemical analysis of enzymes were also carried out. In order to get insight into the interaction of the enzyme with other proteins, the STRING server was used. The secondary structure of the enzyme is mainly composed of random coils and alpha-helices. However, these outcomes should further be validated by wet-lab investigations.


Assuntos
Proteínas de Bactérias/genética , Liases de Carbono-Enxofre/genética , Proteínas de Bactérias/química , Liases de Carbono-Enxofre/química , Citrobacter/enzimologia , Citrobacter/genética , Clostridium/enzimologia , Clostridium/genética , Escherichia/enzimologia , Escherichia/genética , Patentes como Assunto , Filogenia , Pseudomonas/enzimologia , Pseudomonas/genética
4.
Biologia (Bratisl) ; 76(11): 3465-3476, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34421121

RESUMO

The ongoing global pandemic caused by severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) has prompted worldwide vaccine development. Several vaccines have been authorized by WHO, FDA, or MOH of different countries. However, issues such as need for cold chain, price, and most importantly access problems have limited vaccine usage in some nations especially developing countries. Moreover, the vast global demand justifies further attempts for vaccine development. Multi-epitope polypeptide vaccines enjoy several key features including safety and lower production and transfer costs and could be designed by in silico tools. Spike protein (S), membrane protein (M), and nucleocapsid protein (N), the three major structural proteins of SARS-CoV-2, are ideal candidates for epitope selection. ORF3a (open reading frame3a), a transmembrane protein with pro-apoptotic functions, could be another proper target. Thus, a novel multi-epitope vaccine against SARS-CoV-2 was designed using these four proteins and LL37, a TLR3 agonist adjuvant, through different immunoinformatics and bioinformatics tools. The proposed multi-epitope vaccine is expected to induce robust humoral and cellular immune responses against SARS-CoV-2 with a population coverage of 76.92 % due to containing different immunodominant epitopes and LL37 adjuvant. Selecting epitopes derived from one functional and three structural proteins suggests the protective ability of the vaccine irrespective of probable virus mutations. The computationally observed proper interaction of LL37 with TLR3 implies its ability to induce immune responses effectively. Besides, it showed acceptable structural and physicochemical properties. The in-silico cloning results predicted its high efficiency production in Escherichia coli. Future experimental studies could further confirm its immunological efficacy. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1007/s11756-021-00866-y.

5.
Eur J Pharm Sci ; 159: 105718, 2021 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-33465476

RESUMO

The poor immunogenicity of peptide vaccines compared to conventional ones re usually improved by applying different adjuvants. As chemical or biological substances, adjuvants are added to vaccines to enhance and prolong the immune response. According to considerable investigations over the recent years in the context of finding new adjuvants, a handful of vaccine adjuvants have been licensed for human use. Recently, engineered nanoparticles (NPs) have been introduced as novel alternatives to traditional vaccine adjuvant. Metallic nanoparticles (MeNPs) are among the most promising NPs used for vaccine adjuvant as well as the delivery system that can improve immune responses against pathogens. Iron NPs, as an important class of MeNPs, have gained increasing attention as novel vaccine adjuvants. These particles have shown acceptable results in preclinical studies. Hence, understanding the physicochemical properties of iron NPs, including size, surface properties, charge and route of administration, is of substantial importance. The aim of this review is to provide an overview of the immunomodulatory effects of iron NPs as novel adjuvants. Furthermore, physicochemical properties of these NPs were also discussed.


Assuntos
Ferro , Nanopartículas , Adjuvantes Imunológicos , Humanos , Vacinas de Subunidades Antigênicas
6.
Expert Opin Biol Ther ; 21(3): 371-394, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-32945228

RESUMO

INTRODUCTION: Extracellular vesicles (EVs) are cell-created delivery systems of proteins, lipids, or nucleic acids, and means of extracellular communication. Though sEVs were initially considered to be the waste disposal mechanism, today they are at the forefront of research with different biological and pathological functions. Such EVs play a key role in the immunoregulation, CNS development, nervous system physiology, mammary gland development, induction of immunosuppression in pregnancy, the developmental signaling pathways, regeneration of different tissues, inflammation, angiogenesis, coagulation, apoptosis, stem cell differentiation, and extracellular matrix turnover. AREAS COVERED: SEVs contribute to the pathogenesis of different cancers and the progression of various neurodegenerative diseases, infections, as well as metabolic and cardiovascular diseases. Expert Opinion: There is no exact classification for EVs; however, according to size, density, morphological features, content, and biogenesis, they can be categorized into three major classes: microvesicles (ectosomes or microparticles), apoptotic bodies, and sEVs. SEVs, as an important class of EVs, have a crucial role in distinct biological functions. Moreover, shedding light on different structural and molecular aspects of sEV has led to their application in various therapeutic, diagnostic, and drug delivery fields. In this review, we have endeavored to elaborate on different aspects of EVs, especially sEVs.


Assuntos
Vesículas Extracelulares , Neoplasias , Sistemas de Liberação de Medicamentos , Humanos , Neoplasias/tratamento farmacológico , Neovascularização Patológica , Proteínas
7.
Mycopathologia ; 185(6): 1077-1084, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33009966

RESUMO

Although patients with severe immunodeficiency and hematological malignancies has been considered at highest risk for invasive fungal infection, patients with severe pneumonia due to influenza, and severe acute respiratory syndrome coronavirus (SARS-CoV) are also at a higher risk of developing invasive pulmonary aspergillosis (IPA). Recently, reports of IPA have also emerged among SARS-CoV-2 infected patients admitted to intensive care units (ICUs). Here, we report a fatal case of probable IPA in an acute myeloid leukemia patient co-infected with SARS-CoV-2 and complicated by acute respiratory distress syndrome (ARDS). Probable IPA is supported by multiple pulmonary nodules with ground glass opacities which indicate halo sign and positive serum galactomannan results. Screening studies are needed to evaluate the prevalence of IPA in immunocompromised patients infected with SARS-CoV-2. Consequently, testing for the presence of Aspergillus in lower respiratory secretions and galactomannan in consecutive serum samples of COVID-19 patients with timely and targeted antifungal therapy based on early clinical suspicion of IPA are highly recommended.


Assuntos
COVID-19/complicações , COVID-19/mortalidade , Aspergilose Pulmonar Invasiva/etiologia , Aspergilose Pulmonar Invasiva/mortalidade , Leucemia Mieloide Aguda/complicações , Leucemia Mieloide Aguda/mortalidade , SARS-CoV-2/patogenicidade , Adulto , COVID-19/sangue , Evolução Fatal , Feminino , Galactose/análogos & derivados , Humanos , Irã (Geográfico) , Leucemia Mieloide Aguda/sangue , Mananas/sangue
8.
Infect Drug Resist ; 13: 2723-2731, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32801806

RESUMO

PURPOSE: The incidence of Clostridioides difficile infection (CDI) has been reported as 10-fold higher among the elderly population than in young adults. The aim of this study was to compare the targeted bacteria population in the fecal microbiota in two groups of hospitalized elderly, categorized according to CDI and non-CDI. PATIENT AND METHODS: In this case-control study, 84 fecal samples of the 28 patients with CDI and 56 non-CDI patients (>65 years) were studied. C. difficile isolates were characterized by anaerobic culture and multiplex PCR. Quantitative PCR was used to analyze the bacterial elements. RESULTS: CDI group differed significantly for a prolonged hospital stay, previous surgery, residence in nursing home and exposure to a range of antibiotics including quinolone, clindamycin and cephalosporin. CDI group had significantly fewer members of Bacteroides spp., Clostridium cluster IV, Bifidobacterium spp., Faecalibacterium prausnitzii, and Prevotella spp. in their fecal microbiota than the control group (P < 0.05). The abundances of Akkermansia muciniphila, Lactobacillus spp., Escherichia coli and Klebsiella spp. were higher in group CDI compared with the control group (P < 0.05). CONCLUSION: CDI status is associated with the abundance of some bacterial populations. In this study, an increase in Akkermansia muciniphila, Lactobacillus spp., and Enterobacteriaceae genus was highlighted in CDI patients. A reduction in butyrate-producing bacteria was found in CDI patients. The differences in the composition of fecal microbiota can help to understand how antimicrobial agents impact on gut homeostasis and lead to loss of colonization resistance to C. difficile.

9.
AIMS Microbiol ; 6(2): 152-161, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32617447

RESUMO

Leishmaniasis, as a tropical and subtropical disease, is endemic in more than 90 countries around the world. Today, cutaneous leishmaniasis (CL) that affects more than 1.5 million people per year lacks a definitive treatment approach. Imatinib is an anticancer drug that inhibits the abnormal function of Bcr-Abl due to its tyrosine kinase inhibitor, and that was the reason why the drug was tested for CL treatment because protein kinases are essential enzymes in the Leishmania genus. In this study, the L. major CL model of Balb/c mice was produced by injection of the cultured metacyclic form of parasite at the base of the tail. The possible recovery of CL ulcers and determination of the optimum dose of imatinib against Leishmania amastigotes were evaluated. A significant decrease was observed in mice treated with amphotericin B (positive control group) as well as imatinib 50 mg/kg compared to the unreceived drug, negative control group (P<0.05). This study could be promising in gaining insight into the potential of imatinib as an effective treatment approach against CL.

10.
Expert Opin Biol Ther ; 19(12): 1275-1287, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31382850

RESUMO

Introduction: Peptide molecules are being vastly investigated as an emerging class of therapeutic molecules in recent years. Currently, 60 peptides have been approved by the US Food and Drug Administration (FDA), and more would enter the market in near future. Peptides have already opened their ways into cosmeceutical and food industries as well.Areas covered: Antibodies, vaccines, and antimicrobial agents are the major classes of therapeutic peptides. Additionally, peptides may be employed in drug development to support cell penetration or targeting. The interest in antimicrobial peptides is surging due to the increasing risk of antibiotic-resistant pathogens. Peptide vaccines with their significant advantages compared with traditional vaccines, are expected to find their place in coming years, especially for cancer, microbial and allergen-specific immunotherapy. The usage of peptides in cosmeceuticals is also growing rapidly.Expert opinion: Peptide synthesis has become accessible, and advances in peptide engineering, sequencing technologies, and structural bioinformatics have resulted in the rational designing of novel peptides. All these advancements would lead to the more prominent roles of peptides in the mentioned areas. In this review, we discuss applications of peptides in different fields including pharmaceuticals, cosmeceuticals, besides the critical factors in designing efficient peptide molecules.


Assuntos
Cosmecêuticos/farmacologia , Peptídeos/farmacologia , Anti-Infecciosos , Cosmecêuticos/química , Humanos , Peptídeos/química , Vacinas
11.
Curr Pharm Biotechnol ; 18(7): 531-540, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28786356

RESUMO

BACKGROUND: Among therapeutic proteins, enzymes represent small and of course profitable market. They can be used to treat important, rare, and deadly diseases. Enzyme therapy is the only available treatment for certain disorders. METHOD: Here, pharmaceutical enzymes are reviewed. They are categorized in four main groups, enzymes in replacement therapy, enzymes in cancer treatment, enzymes for fibrinolysis, and finally enzymes that are used topically for various treatments. Furthermore, enzyme gene therapy and future perspective of therapeutic enzymes are mentioned in brief. RESULTS: There are many important approved enzymes in pharmaceutical market. Several approaches such as point mutation, fusion protein designing, glycoengineering, and PEGylation were used to achieve improved enzymes. Although sometimes enzymes were engineered to facilitate production and purification process, appropriate delivery to target sites, extending half-life, and reducing immunogenicity are among the main goals of engineering approaches. CONCLUSION: Overall, enzymes play a critical role in treatment of common and rare diseases. Evaluation of new enzymes as well as improvement of approved enzymes are of the most important challenges in biotechnology.


Assuntos
Biotecnologia/métodos , Terapia de Reposição de Enzimas , Terapia Enzimática , Engenharia de Proteínas/métodos , Sistemas de Liberação de Medicamentos , Desenho de Fármacos , Enzimas/genética , Enzimas/farmacocinética , Meia-Vida , Humanos
12.
Biotechnol Lett ; 39(6): 785-803, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28238060

RESUMO

With ever-increasing molecular information about colorectal cancer (CRC), there is an expectation to detect more sensitive and specific molecular markers for new advanced diagnostic methods that can surpass the limitations of current screening tests. Moreover, enhanced molecular pathology knowledge about cancer has led to the development of targeted therapies, designed to interfere with specific aberrant biological pathways in cancer. Furthermore, biotechnology has opened a new window in CRC diagnosis and treatment by introducing different application of antibodies, antibody fragments, non-Ig scaffold proteins, and aptamers in targeted therapy and drug delivery. This review summarizes the molecular diagnostic and therapeutic approaches in CRC with a focus on genetic and epigenetic alterations, protein and metabolite markers as well as targeted therapy and drug delivery by Ig-scaffold proteins, non-Ig scaffold proteins, nanobodies, and aptamers.


Assuntos
Biotecnologia/métodos , Neoplasias Colorretais , Sistemas de Liberação de Medicamentos , Técnicas de Diagnóstico Molecular , Neoplasias Colorretais/diagnóstico , Neoplasias Colorretais/terapia , Humanos
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA