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1.
Molecules ; 27(2)2022 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-35056889

RESUMO

Brain cancer treatment, where glioblastoma represents up to 50% of all CNS malignancies, is one of the most challenging calls for neurooncologists. The major driver of this study was a search for new approaches for the treatment of glioblastoma. We tested live S. pyogenes, cathelicidin family peptides and NGF, assessing the oncolytic activity of these compounds as monotherapy or in combination with chemotherapeutics. For cytotoxicity evaluation, we used the MTT assay, trypan blue assay and the xCELLigence system. To evaluate the safety of the studied therapeutic approaches, we performed experiments on normal human fibroblasts. Streptococci and peptides demonstrated high antitumor efficiency against glioma C6 cells in all assays applied, surpassing the effect of chemotherapeutics (doxorubicin, carboplatin, cisplatin, etoposide). A real-time cytotoxicity analysis showed that the cell viability index dropped to 21% 2-5 h after S. pyogenes strain exposure. It was shown that LL-37, PG-1 and NGF also exhibited strong antitumor effects on C6 glioma cells when applied at less than 10-4 M. Synergistic effects for combinations of PG-1 with carboplatin and LL-37 with etoposide were shown. Combinations of S. pyogenes strain #7 with NGF or LL-37 demonstrated a cytotoxic effect (56.7% and 57.3%, accordingly) on C6 glioma cells after 3 h of exposure.


Assuntos
Peptídeos Catiônicos Antimicrobianos , Catelicidinas
2.
Cancer ; 122(13): 2050-6, 2016 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-27191689

RESUMO

BACKGROUND: Previous results from an interim analysis of an open-label, randomized, phase 3 study demonstrated that bortezomib combined with pegylated liposomal doxorubicin (PLD) was superior to bortezomib monotherapy in patients with relapsed/refractory multiple myeloma who had previously received one or more lines of therapy. Protocol-defined final survival data from that study are provided here. METHODS: Patients were randomized (1:1) to receive either bortezomib alone (1.3 mg/m(2) intravenously on days 1, 4, 8, and 11 of every 21-day cycle) or bortezomib-PLD (bortezomib plus PLD 30 mg/m(2) intravenously on day 4). The primary endpoint was the time to progression. Secondary efficacy endpoints included overall survival (OS), progression-free survival, and the overall response rate. RESULTS: In total, 646 patients (bortezomib-PLD, n = 324; bortezomib alone, n = 322) were randomized between December, 2004, and March, 2006. On the clinical cutoff date (May 16, 2014) for the final survival analysis, at a median follow-up of 103 months, 79% of patients had died (bortezomib-PLD group: 253 of 324 patients; 78%; bortezomib alone group: 257 of 322 patients; 80%). The median OS in the bortezomib-PLD group was 33 months (95% confidence interval [CI], 28.9-37.1) versus 30.8 months (95% CI, 25.2-36.5) in the bortezomib alone group (hazard ratio, 1.047; 95% CI, 0.879-1.246; P = .6068). Salvage therapies included conventional and novel drugs, which were well balanced between the two treatment groups. CONCLUSIONS: Despite inducing a superior time to progression, long-term follow-up revealed that PLD-bortezomib did not improve OS compared with bortezomib alone in patients with relapsed/refractory multiple myeloma. The inability to sustain the early observed survival advantage may have been caused by the effects of subsequent lines of therapy, and underscores the need for long-term follow-up of phase 3 trials while recognizing the challenge of having adequate power to detect long-term differences in OS. Cancer 2016;122:2050-6. © 2016 American Cancer Society.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Bortezomib/administração & dosagem , Doxorrubicina/análogos & derivados , Mieloma Múltiplo/tratamento farmacológico , Recidiva Local de Neoplasia/tratamento farmacológico , Administração Intravenosa , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Bortezomib/uso terapêutico , Intervalo Livre de Doença , Doxorrubicina/administração & dosagem , Doxorrubicina/uso terapêutico , Esquema de Medicação , Feminino , Humanos , Masculino , Mieloma Múltiplo/mortalidade , Polietilenoglicóis/administração & dosagem , Polietilenoglicóis/uso terapêutico , Resultado do Tratamento
3.
World J Clin Cases ; 11(20): 4740-4751, 2023 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-37583996

RESUMO

The article discusses various approaches for probiotic treatment of Helicobacter pylori (H. pylori) infection: Probiotics as an adjuvant treatment in the standard eradication therapy; probiotic strains as a monotherapy; and autoprobiotics as a monotherapy. Autoprobiotics refer to indigenous bifidobacteria, lactobacilli, or enterococci isolated from a specific individual, intended to restore his/her microbiota and improve his/her health. The potential mechanisms of probiotic action against H. pylori include correction of the gut microbiota, immunological effects (enhancement of humoral and cellular immunity, and reduction of oxidative stress), direct antagonistic effects against H. pylori (such as colonization resistance and bacteriocin synthesis), and stimulation of local immunological protection (strengthening of the mucous protective barrier and reduction of gastric mucosa inflammation). The incorporation of probiotics into comprehensive eradication therapy shows promise in optimizing the treatment of H. pylori infection. Probiotics can enhance the eradication rates of H. pylori, reduce the occurrence and severity of side effects, and improve patient compliance. Probiotic or autoprobiotic monotherapy can be considered as an alternative treatment approach in cases of allergic reactions and insufficient effectiveness of antibiotics. We recommend including probiotics as adjunctive medications in anti-H. pylori regimens. However, further randomized multicenter studies are necessary to investigate the effects of probiotics and autoprobiotics against H. pylori, in order to gain a better understanding of their mechanisms of action.

4.
Microorganisms ; 10(11)2022 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-36422363

RESUMO

In this study, we investigated the effect of three different probiotics, namely, a combination of Lactobacillus acidophilus (LA-5) and Bifidobacterium animalis subsp. lactis (BB-12), Saccharomyces boulardii, and Enterococcus faecium L3 on myocardial infarct size in rats with diet-induced obesity (DIO) and chemically-induced colitis (CIC). Potential associations between the effects of probiotics on myocardial ischemia-reperfusion injury and gut microbiome patterns as well as the serum levels of pro- and anti-inflammatory cytokines, lipopolysaccharide, and short chain fatty acids were also studied. Intragastric administration of lyophilized Lactobacillus acidophilus and Bifidobacterium animalis subsp. lactis at a dose of 1.2 × 108 CFU/mL for 15 days resulted in myocardial infarct size reduction in rats with DIO, CIC, and antibiotic-induced dysbiosis. This cardioprotective effect was associated with specific changes in cytokine concentrations, namely reduced levels of IL-1ß, TNF-α, IL-2, and IL-8. At the same time, the use of Lactobacillus acidophilus and Bifidobacterium animalis subsp. lactis was accompanied by a significant reduction in lipopolysaccharide level, suggesting normalization of intestinal epithelial barrier permeability. However, the cardioprotective effect of Lactobacillus acidophilus and Bifidobacterium animalis subsp. lactis is not secondary to improved healing of the intestinal mucosa in CIC, as evidenced by the lack of difference in histopathological scores.

5.
Helicobacter ; 15(3): 193-200, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20557360

RESUMO

BACKGROUND: Helicobacter pylori strains expressing cytotoxic CagA protein are more likely to provoke severe gastric mucosal pathology and cause adenocarcinoma development than that lacking CagA. Determination of the CagA-status of a pathogen, therefore, is regarded as informative approach in H. pylori infection diagnostics and disease risk prediction. MATERIALS AND METHODS: Molecular cloning, recombinant protein expression in Escherichia coli, affinity chromatography, electrophoresis and commonly used techniques of hybridoma production and screening were used as well as different immunosorbent assays and Western blot procedures. RESULTS: Four overlapping N-terminally His(6)-tagged recombinant fragments of CagA that covered the entire CagA sequence were produced and purified. An ELISA for specific anti-CagA serum antibodies detection was developed and evaluated. Utilizing recombinant fragments, the first set of monoclonal antibodies against CagA-antigen was produced and characterized. Three antibodies recognized distinct linear epitopes inside conserved regions of the cytotoxin whereas the epitope of the forth antibody was mapped in the variable area of CagA. The monoclonal antibodies allowed discriminating CagA-positive and CagA-negative H. pylori strains by means of Western blot and immunosorbent assays. CONCLUSIONS: The use of recombinant protein technology allowed obtaining pure CagA antigen, thus providing new perspectives for development of immunodiagnostic reagents. The set of monoclonal antibodies is a valuable tool for determination of CagA-status of H. pylori infection and for the investigation of cytotoxin molecule as well.


Assuntos
Antígenos de Bactérias/análise , Proteínas de Bactérias/análise , Técnicas Bacteriológicas/métodos , Infecções por Helicobacter/microbiologia , Helicobacter pylori/química , Fatores de Virulência/análise , Animais , Anticorpos Antibacterianos/isolamento & purificação , Anticorpos Monoclonais/isolamento & purificação , Western Blotting/métodos , Helicobacter pylori/isolamento & purificação , Helicobacter pylori/patogenicidade , Humanos , Técnicas de Imunoadsorção , Camundongos , Camundongos Endogâmicos BALB C
6.
Heliyon ; 5(2): e01154, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30839941

RESUMO

We are developing an associated vaccine based on live influenza vaccine (LAIV) and streptococcal recombinant peptides. The recombinant group B streptococcus (GBS) peptides P6 and ScaAB demonstrated a distinguished immunomodulating effect in THP-1 cells. The increase in IFN 1-alpha expression after ScaAB inoculation was similar to that against LAIV. We immunized mice intranasal using of A/H7N3 LAIV or/and ScaAB peptide. At day 5 after immunization, we detected serum IgM which reacted with non-vaccine influenza viruses. Associated vaccination of mice using LAIV and GBS peptide was the most effective against sub-lethal infection with A/H7N9 influenza virus and against lethal challenge with A/H1N1pdm virus at day 5 after immunization. Not only LAIV but also the ScaAB protected about 20% of the immunized animals against lethal challenge with A/H1N1pdm virus. The early protection was related to increasing type 1 interferons expression in the lungs. Our results in mice have shown that successful protection against homologous and heterologous influenza infections can be achieved soon after vaccination with either LAIV or LAIV in combination with GBS recombinant peptide. Presumably, such protection may be mediated by non-specific IgM antibodies and an increase in the expression of early cytokines in the airway.

7.
J Bacteriol ; 190(23): 7773-85, 2008 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-18820018

RESUMO

The 1,815,783-bp genome of a serotype M49 strain of Streptococcus pyogenes (group A streptococcus [GAS]), strain NZ131, has been determined. This GAS strain (FCT type 3; emm pattern E), originally isolated from a case of acute post-streptococcal glomerulonephritis, is unusually competent for electrotransformation and has been used extensively as a model organism for both basic genetic and pathogenesis investigations. As with the previously sequenced S. pyogenes genomes, three unique prophages are a major source of genetic diversity. Two clustered regularly interspaced short palindromic repeat (CRISPR) regions were present in the genome, providing genetic information on previous prophage encounters. A unique cluster of genes was found in the pathogenicity island-like emm region that included a novel Nudix hydrolase, and, further, this cluster appears to be specific for serotype M49 and M82 strains. Nudix hydrolases eliminate potentially hazardous materials or prevent the unbalanced accumulation of normal metabolites; in bacteria, these enzymes may play a role in host cell invasion. Since M49 S. pyogenes strains have been known to be associated with skin infections, the Nudix hydrolase and its associated genes may have a role in facilitating survival in an environment that is more variable and unpredictable than the uniform warmth and moisture of the throat. The genome of NZ131 continues to shed light upon the evolutionary history of this human pathogen. Apparent horizontal transfer of genetic material has led to the existence of highly variable virulence-associated regions that are marked by multiple rearrangements and genetic diversification while other regions, even those associated with virulence, vary little between genomes. The genome regions that encode surface gene products that will interact with host targets or aid in immune avoidance are the ones that display the most sequence diversity. Thus, while natural selection favors stability in much of the genome, it favors diversity in these regions.


Assuntos
Genoma Bacteriano , Streptococcus pyogenes/classificação , Streptococcus pyogenes/genética , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Cromossomos Bacterianos , Elementos de DNA Transponíveis/genética , Perfilação da Expressão Gênica , Variação Genética , Família Multigênica , Prófagos/genética , Pirofosfatases/genética , Streptococcus pyogenes/patogenicidade , Virulência , Nudix Hidrolases
8.
Genome Announc ; 5(38)2017 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-28935732

RESUMO

We present here the complete genome sequence of Streptococcus pyogenes type emm111 strain GUR, a throat isolate from a scarlet fever patient, which has been used to treat cancer patients in the former Soviet Union. We also present the complete genome sequence of its derivative strain GURSA1 with an inactivated emm gene.

9.
Virology (Auckl) ; 8: 1178122X17710949, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28615930

RESUMO

We investigate the protective effect of combined vaccination based on live attenuated influenza vaccine (LAIV) and group B streptococcus (GBS) recombinant polypeptides against potential pandemic H7N9 influenza infection followed by GBS burden. Mice were intranasally immunized using 107 50% egg infectious dose (EID50) of H7N3 LAIV, the mix of the 4 GBS peptides (group B streptococcus vaccine [GBSV]), or combined LAIV + GBSV vaccine. The LAIV raised serum hemagglutination-inhibition antibodies against H7N9 in higher titers than against H7N3. Combined vaccination provided advantageous protection against infections with A/Shanghai/2/2013(H7N9)CDC-RG influenza and serotype II GBS. Combined vaccine significantly improved bacterial clearance from the lungs after infection compared with other vaccine groups. The smallest lung lesions due to combined LAIV + GBSV vaccination were associated with a prevalence of lung interferon-γ messenger RNA expression. Thus, combined viral and bacterial intranasal immunization using H7N3 LAIV and recombinant bacterial polypeptides induced balanced adaptive immune response, providing protection against potential pandemic influenza H7N9 and bacterial complications.

10.
Open Microbiol J ; 10: 168-175, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27867430

RESUMO

BACKGROUND: Secondary bacterial influenza complications are a common cause of excesses morbidity and mortality, which determines the need to develop means for specific prophylaxis. Group B streptococcal infection is especially common cause of pneumonia among children and the elderly with underlying conditions. Here we investigate in a mouse model the effects of combined intranasal immunization using live attenuated influenza vaccine and recombinant polypeptides based on group B Streptococcus surface proteins. METHODS: Groups of outbred mice received two doses of the following preparations: 1) the reassortant A/17/Mallard/Netherlands/00/95 (H7N3) influenza virus; 2) a mixture of P6, ScaAB, ScpB1 and Stv recombinant GBS proteins (20 µg total); 3) the A(H7N3) influenza vaccine pooled with the four bacterial peptide preparation; 4) control animals were treated with PBS. RESULTS: Intranasal vaccination using LAIV in combination with GBS polypeptides provided advantageous protection against infections with homologous A/Mallard/Netherlands/12/00 (H7N3) wild type virus or heterologous A/Puerto Rico/8/34 (H1N1) followed by serotype II GBS infection. Also, combined vaccination improved bacterial clearance from the lungs of mice. CONCLUSION: Intranasal immunization with LAIV+GBSV was safe and enabled to induce the antibody response to each of vaccine components. Thus, the combined vaccine increased the protective effect against influenza and its bacterial complications in mice compared to LAIV-only.

11.
FEMS Microbiol Lett ; 294(1): 9-15, 2009 May.
Artigo em Inglês | MEDLINE | ID: mdl-19493003

RESUMO

Bacteriophages are common autonomous migrating mobile genetic elements in group A Streptococcus (GAS) and are often associated with the carriage of various virulence genes, including toxins, mitogens and enzymes. Two collections of GAS type M49 strains isolated from invasive (22 strains) and noninvasive (16 strains) clinical cases have been studied for the presence of phage and phage-associated virulence genes. All the GAS strains carried from at least two to six phage genomes as determined by the number of known phage integrase genes found. A sampling of the invasive M49 strains showed that they belonged to the same multilocus sequence typing type, carried two specific integrase genes (int5 and int7), and contained the toxin genes speA, speH and speI. Other invasive strains lacking this gene profile carried the prophage integrating in mutL-mutS region and inducing the 'mutator' phenotype. We suggest that this specific phage-related virulence gene constellation might be an important factor increasing M49 GAS pathogenicity.


Assuntos
Prófagos/isolamento & purificação , Fagos de Streptococcus/isolamento & purificação , Streptococcus pyogenes/virologia , Antígenos de Bactérias/biossíntese , Proteínas da Membrana Bacteriana Externa/biossíntese , Proteínas de Bactérias/genética , Proteínas de Transporte/biossíntese , Análise por Conglomerados , Impressões Digitais de DNA , DNA Viral/genética , Desoxirribonucleases de Sítio Específico do Tipo II/genética , Exotoxinas/genética , Humanos , Integrases/genética , Proteínas de Membrana/genética , Prófagos/classificação , Prófagos/genética , Análise de Sequência de DNA , Infecções Estreptocócicas/microbiologia , Fagos de Streptococcus/classificação , Fagos de Streptococcus/genética , Streptococcus pyogenes/isolamento & purificação , Proteínas Virais/genética , Fatores de Virulência/genética
12.
J Clin Oncol ; 25(25): 3892-901, 2007 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-17679727

RESUMO

PURPOSE: This phase III international study compared the efficacy and safety of a combination of pegylated liposomal doxorubicin (PLD) plus bortezomib with bortezomib monotherapy in patients with relapsed or refractory multiple myeloma. PATIENTS AND METHODS: Six hundred forty-six patients were randomly assigned to receive either intravenous bortezomib 1.3 mg/m(2) on days 1, 4, 8, and 11 of an every 21-days cycle, or the same bortezomib regimen with PLD 30 mg/m(2) on day 4. RESULTS: Median time to progression was increased from 6.5 months for bortezomib to 9.3 months with the PLD + bortezomib combination (P = .000004; hazard ratio, 1.82 [monotherapy v combination therapy]; 95% CI, 1.41 to 2.35). The 15-month survival rate for PLD + bortezomib was 76% compared with 65% for bortezomib alone (P = .03). The complete plus partial response rate was 41% for bortezomib and 44% for PLD + bortezomib, a difference that was not statistically significant. Median duration of response was increased from 7.0 to 10.2 months (P = .0008) with PLD + bortezomib. Grade 3/4 adverse events were more frequent in the combination group (80% v 64%), with safety profiles consistent with the known toxicities of the two agents. An increased incidence in the combination group was seen of grade 3/4 neutropenia, thrombocytopenia, asthenia, fatigue, diarrhea, and hand-foot syndrome. CONCLUSION: PLD with bortezomib is superior to bortezomib monotherapy for the treatment of patients with relapsed or refractory multiple myeloma. The combination therapy is associated with a higher incidence of grade 3/4 myelosuppression, constitutional symptoms, and GI and dermatologic toxicities.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Ácidos Borônicos/administração & dosagem , Doxorrubicina/análogos & derivados , Mieloma Múltiplo/tratamento farmacológico , Polietilenoglicóis/administração & dosagem , Pirazinas/administração & dosagem , Adulto , Idoso , Idoso de 80 Anos ou mais , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Bortezomib , Doenças Cardiovasculares/induzido quimicamente , Doenças Cardiovasculares/epidemiologia , Progressão da Doença , Intervalo Livre de Doença , Doxorrubicina/administração & dosagem , Resistencia a Medicamentos Antineoplásicos , Feminino , Doenças Hematológicas/induzido quimicamente , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia
13.
J Basic Microbiol ; 44(1): 66-74, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-14768030

RESUMO

A subtraction library of group B streptococcus (GBS) strain O9OR with GAS chromosomal DNA (strain SF370) was constructed and more than 100 plasmid clones sequenced. DNA sequences of the plasmid inserts were analyzed using the BLAST gene search. Most inserts had little or no homology to GAS chromosomal DNA and 26 clones from the library had no gene homologues in the gene bank. The majority of genes discovered represented house keeping GBS genes, but several could be considered as possible virulence factors. Inserts from 21 clones were labeled and used as probes for hybridization with GBS DNA fragments separated by pulsed field electrophoresis. A genetic map of GBS strain O9OR was constructed.


Assuntos
Cromossomos Bacterianos/genética , Biblioteca Gênica , Genes Bacterianos , Streptococcus agalactiae/genética , Streptococcus pyogenes/genética , Mapeamento Cromossômico , DNA Bacteriano/química , DNA Bacteriano/isolamento & purificação , Eletroforese em Gel de Campo Pulsado , Genoma Bacteriano , Mapeamento Físico do Cromossomo , Mapeamento por Restrição , Análise de Sequência de DNA , Fatores de Virulência/genética
14.
J Bacteriol ; 184(22): 6384-6, 2002 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-12399509

RESUMO

The 3' ends of the genes for the C-terminal region of C5a peptidase from 15 Streptococcus pyogenes isolates were analyzed by PCR. Amplicons were found to differ in size. DNA sequence analysis revealed that the differences between PCR fragment sizes accorded with the number of R repeats in the C5a peptidase gene.


Assuntos
Adesinas Bacterianas , Endopeptidases/química , Endopeptidases/genética , Variação Genética , Streptococcus pyogenes/enzimologia , Streptococcus pyogenes/genética , Sequência de Aminoácidos , DNA Bacteriano/análise , DNA Bacteriano/isolamento & purificação , Humanos , Dados de Sequência Molecular , Reação em Cadeia da Polimerase , RNA Ribossômico 16S/genética , Ribotipagem , Análise de Sequência de DNA , Infecções Estreptocócicas/microbiologia , Streptococcus pyogenes/isolamento & purificação
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