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PURPOSE: This systematic review updates the MASCC/ESMO recommendations for high-emetic-risk chemotherapy (HEC) published in 2016-2017. HEC still includes cisplatin, carmustine, dacarbazine, mechlorethamine, streptozocin, and cyclophosphamide in doses of > 1500 mg/m2 and the combination of cyclophosphamide and an anthracycline (AC) in women with breast cancer. METHODS: A systematic review report following the PRISMA guidelines of the literature from January 1, 2015, until February 1, 2023, was performed. PubMed (Ovid), Scopus (Google), and the Cochrane Database of Systematic Reviews were searched. The literature search was limited to randomized controlled trials, systematic reviews, and meta-analyses. RESULTS: Forty-six new references were determined to be relevant. The main topics identified were (1) steroid-sparing regimens, (2) olanzapine-containing regimens, and (3) other issues such as comparisons of antiemetics of the same drug class, intravenous NK1 receptor antagonists, and potentially new antiemetics. Five updated recommendations are presented. CONCLUSION: There is no need to prescribe steroids (dexamethasone) beyond day 1 after AC HEC, whereas a 4-day regimen is recommended in non-AC HEC. Olanzapine is now recommended as a fixed part of a four-drug prophylactic antiemetic regimen in both non-AC and AC HEC. No major differences between 5-HT3 receptor antagonists or between NK1 receptor antagonists were identified. No new antiemetic agents qualified for inclusion in the updated recommendations.
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Antieméticos , Antineoplásicos , Femenino , Humanos , Eméticos , Antieméticos/uso terapéutico , Consenso , Olanzapina , Náusea/inducido químicamente , Náusea/prevención & control , Vómitos/inducido químicamente , Vómitos/prevención & control , Antineoplásicos/efectos adversos , Ciclofosfamida , AntraciclinasRESUMEN
This review summarizes the most relevant advances in the biological transformation of fatty acids (or derivatives) into hydrocarbons to be used as biofuels (biogasoline, green diesel and jet biofuel). Among the used enzymes, the fatty acid decarboxylase from Jeotgalicoccus sp. ATCC 8456 (OleTJE) stands out as a promising enzyme. OleTJE may be coupled in cascade reactions with metalloenzymes or reductases from the Old Yellow Enzymes (OYE) family to perform the hydrogenation of α-olefins into paraffins. The photodecarboxylase from Chlorella variabilis NC64A (CvFAP) is an example of coupling biocatalysis and photocatalysis to produce alkanes. Besides the (photo)decarboxylation of free fatty acids and/or triacyclglycerols to produce alkanes/alkenes, by enzymes has also been employed. The cyanobacterial aldehyde decarbonylase (cAD) from Nostoc punctiforme is an outstanding example of this kind of enzymes used to produce alkanes. Overall, these kinds of enzymes open up new possibilities to the production of biofuels from renewable sources, even if they have many limitations on the current situation. The possibilities of improving enzymes features via immobilization or coimmobilization, as well as the utilization of whole cells haves been also reviewed.
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Alcanos , Chlorella , Alquenos , Biocombustibles , Triglicéridos , Ácidos GrasosRESUMEN
We propose a pore size analysis methodology for carbonaceous materials that reduces complexity while maintaining the significant elements of the structure-property relationship. This method chooses a limited number of representative pores, which will constitute a simplified kernel to describe the pore size distribution (PSD) of an activated carbon. In this study we use the representative pore sizes of 7.0, 8.9, 18.5, and 27.9 Å and N2 isotherms at 77.4 K to determine the PSD which is later applied to predict the adsorption equilibrium of other gases. In this study we demonstrate the ability to predict adsorption of different gas molecules on activated carbon from the PSD generated with representative pores (PSDrep). The methodology allows quick solutions for large-scale calculations for carbonaceous materials screening, in addition to make accessible an easily understood and prompt evaluation of the structure-property relationship of activated carbons. In addition to the details of the methodology already tested in different fields of application of carbonaceous materials, we present a new application related to the removal of organic contaminants in dilute aqueous solutions.
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OBJECTIVE AND DESIGN: Investigate survival outcomes, and immunological and metabolomic effects of hyaluronidase (Hz) treatment during mouse models of acute inflammation and sepsis. METHODS: Survival of C57Bl/6 mice was monitored after lethal challenge with lipopolysaccharide (LPS) or cecal and ligation puncture (CLP)-induced sepsis and treated with Hz or saline. Mice were also challenged with LPS and treated with Hz for leukocyte counting, cytokine quantification and determination of metabolomic profiles in the peritoneal fluid. RESULTS: Hz treatment improved survival outcomes after lethal challenge with LPS or CLP-induced sepsis. LPS challenge promoted acute neutrophil accumulation and production of interleukin-1ß (IL-1ß) and IL-6 in the peritoneum, whereas Hz treatment suppressed neutrophil infiltration and cytokine production. We further characterized the metabolomic alterations caused by LPS challenge, which predicted activity of metabolic pathways related to fatty acids and eicosanoids. Hz treatment had a profound effect over the metabolic response, reflected by reductions of the relative levels of fatty acids. CONCLUSION: Collectively, these data demonstrate that Hz treatment is associated with metabolic reprogramming of pathways that sustain the inflammatory response.
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Hialuronoglucosaminidasa/farmacología , Sepsis/inmunología , Sepsis/metabolismo , Enfermedad Aguda , Animales , Líquido Ascítico/citología , Líquido Ascítico/inmunología , Líquido Ascítico/metabolismo , Modelos Animales de Enfermedad , Eicosanoides/metabolismo , Ácidos Grasos/metabolismo , Inmunomodulación , Interleucina-1beta/inmunología , Interleucina-6/inmunología , Recuento de Leucocitos , Lipopolisacáridos , Masculino , Redes y Vías Metabólicas/efectos de los fármacos , Metabolómica , Ratones Endogámicos C57BLRESUMEN
Paracoccidioidomycosis (PCM) is a systemic mycosis autochthonous to Latin America and endemic to Brazil, which has the majority of the PCM cases. PCM is acquired through the inhalation of propagules of fungi from genus Paracoccidioides spp. and mainly affects the lungs. We have previously shown that P. brasiliensis-infected mice treated with single-dose of recombinant 60-kDa-heat shock protein from P. brasiliensis (rPbHsp60) had a worsening infection in comparison to animals only infected. In this study, we investigate whether the treatment of infected mice with PB_HSP60 gene cloned into a plasmid (pVAX1-PB_HSP60) would result in efficient immune response and better control of the disease. The harmful impact of single-dose therapy with protein was not seen with plasmid preparations. Most importantly, three doses of pVAX1-PB_HSP60 and protein induced a beneficial effect in experimental PCM with a reduction in fungal load and lung injury when compared with infected mice treated with pVAX1 or PBS. The increase of the cytokines IFN-γ, TNF, and IL-17 and the decrease of IL-10 observed after treatment with three doses of pVAX1-PB_HSP60 appears to be responsible for the control of infection. These results open perspectives of the therapeutic use of Hsp60 in PCM.
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Chaperonina 60/inmunología , Vacunas Fúngicas/inmunología , Paracoccidioides/inmunología , Paracoccidioidomicosis/inmunología , Paracoccidioidomicosis/prevención & control , Vacunas de ADN/inmunología , Animales , Antígenos Fúngicos/inmunología , Chaperonina 60/genética , Citocinas/genética , Citocinas/metabolismo , Modelos Animales de Enfermedad , Vacunas Fúngicas/genética , Inmunización , Mediadores de Inflamación/metabolismo , Masculino , Ratones , Paracoccidioides/genética , Paracoccidioidomicosis/genética , Paracoccidioidomicosis/microbiología , Pronóstico , Vacunas de ADN/genéticaRESUMEN
In order to develop an improved BCG vaccine against tuberculosis we have taken advantage of the adjuvant properties of a non-toxic derivative of Escherichia coli heat labile enterotoxin (LT), LTAK63. We have constructed rBCG strains expressing LTAK63 at different expression levels. Mice immunized with BCG expressing low levels of LTAK63 (rBCG-LTAK63lo) showed higher Th1 cytokines and IL-17 in the lungs, and when challenged intratracheally with Mycobacterium tuberculosis displayed a 2.0-3.0 log reduction in CFU as compared to wild type BCG. Histopathological analysis of lung tissues from protected mice revealed a reduced inflammatory response. Immunization with rBCG-LTAK63lo also protected against a 100-fold higher challenge dose. Mice immunized with rBCG-LTAK63lo produced an increase in TGF-ß as compared with BCG after challenge, with a corresponding reduction in Th1 and Th17 cytokines, as determined by Real Time RT-PCR. Furthermore, rBCG-LTAK63lo also displays protection against challenge with a highly virulent Beijing isolate. Our findings suggest that BCG with low-level expression of the LTAK63 adjuvant induces a stronger immune response in the lungs conferring higher levels of protection, and a novel mechanism subsequently triggers a regulatory immune response, which then limits the pathology. The rBCG-LTAK63lo strain can be the basis of an improved vaccine against tuberculosis.
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Vacuna BCG/inmunología , Endotoxinas/inmunología , Tuberculosis/inmunología , Vacunas Sintéticas/inmunología , Adyuvantes Inmunológicos/genética , Animales , Vacuna BCG/genética , Células Cultivadas , Endotoxinas/genética , Pulmón/inmunología , Ratones , Mycobacterium tuberculosis/inmunología , Bazo/inmunología , Vacunas Sintéticas/genéticaRESUMEN
In order to develop an improved BCG vaccine against tuberculosis we have taken advantage of the adjuvant properties of a non-toxic derivative of Escherichia coli heat labile enterotoxin (LT), LTAK63. We have constructed rBCG strains expressing LTAK63 at different expression levels. Mice immunized with BCG expressing low levels of LTAK63 (rBCG-LTAK63(lo)) showed higher Th1 cytokines and IL-17 in the lungs, and when challenged intratracheally with Mycobacterium tuberculosis displayed a 2.0-3.0 log reduction in CFU as compared to wild type BCG. Histopathological analysis of lung tissues from protected mice revealed a reduced inflammatory response. Immunization with rBCG-LTAK63(lo) also protected against a 100-fold higher challenge dose. Mice immunized with rBCG-LTAK63(lo) produced an increase in TGF-beta as compared with BCG after challenge, with a corresponding reduction in Th1 and Th17 cytokines, as determined by Real Time RT-PCR. Furthermore, rBCG-LTAK63(lo) also displays protection against challenge with a highly virulent Beijing isolate. Our findings suggest that BCG with low-level expression of the LTAK63 adjuvant induces a stronger immune response in the lungs conferring higher levels of protection, and a novel mechanism subsequently triggers a regulatory immune response, which then limits the pathology. The rBCG-LTAK63(lo) strain can be the basis of an improved vaccine against tuberculosis.
RESUMEN
In order to develop an improved BCG vaccine against tuberculosis we have taken advantage of the adjuvant properties of a non-toxic derivative of Escherichia coli heat labile enterotoxin (LT), LTAK63. We have constructed rBCG strains expressing LTAK63 at different expression levels. Mice immunized with BCG expressing low levels of LTAK63 (rBCG-LTAK63lo) showed higher Th1 cytokines and IL-17 in the lungs, and when challenged intratracheally with Mycobacterium tuberculosis displayed a 2.03.0 log reduction in CFU as compared to wild type BCG. Histopathological analysis of lung tissues from protected mice revealed a reduced inflammatory response. Immunization with rBCG-LTAK63lo also protected against a 100-fold higher challenge dose. Mice immunized with rBCG-LTAK63lo produced an increase in TGF-β as compared with BCG after challenge, with a corresponding reduction in Th1 and Th17 cytokines, as determined by Real Time RT-PCR. Furthermore, rBCG-LTAK63lo also displays protection against challenge with a highly virulent Beijing isolate. Our findings suggest that BCG with low-level expression of the LTAK63 adjuvant induces a stronger immune response in the lungs conferring higher levels of protection, and a novel mechanism subsequently triggers a regulatory immune response, which then limits the pathology. The rBCG-LTAK63lo strain can be the basis of an improved vaccine against tuberculosis.
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Vacuna BCG , Vacunas contra la TuberculosisRESUMEN
BACKGROUND: The valuable role of immunotherapy in treating autoimmune diseases is increasingly recognized by those involved in the research and clinical application of new biopharmaceuticals products. However, many aspects related to the mechanisms of immune-modulated therapies remain to be elucidated in order to explore fully the emerging opportunities. The non-obese diabetic NOD mouse develops insulin-dependent diabetes mellitus spontaneously as a consequence of an autoimmune process in the presence of pathogenic CD4(+) T cells that typically exhibit Th17 cell phenotypes. The change of a Th17 phenotype into a pattern of regulatory T cells (Treg) is extremely important in controlling autoimmune diseases. Heat shock proteins (HSPs) are stress-induced proteins with immunoregulatory properties. In the current study, the capacity of Hsp65 and Hsp70 mycobacterial HSPs and a constructed DNA encoded Hsp65 (DNAhsp65) to transform the pattern of the immune response from Th17 into Treg cells has been studied in vitro using co-cultures of antigen presenting cells (APCs) and T cells in NOD mice. RESULTS: Cells harvested from NOD mice and cultured for 48 h (without immunoregulatory compounds) presented with Th1/Th17 patterns and secretions of IL-6, IFN-γ, IL-10 and IL-17 cytokines. The cultured cells from the non-diabetic BALB/C mice exhibited a Th1 pattern and the production of IL 6 and IFN-γ secretions. An up-regulation was observed in the supernatants from the co-cultures of NOD cells that were stimulated with DNAhsp65, Hsp65 or Hsp70 through increased levels of IL-10 secretion and the suppression of IL-6, IFN-γ and IL-17 production. In addition, immunoregulation was demonstrated through IL-17 suppression in the co-culture stimulated by the specific insulin antigen. Moreover, an increase of immunoregulatory compounds were observed in the co-culture through the expression of CD11b(+)CD86(+) activation markers on APCs, as well as the frequency of Treg cells expressing CD4(+)CD3(+) and CD4(+)CD25(hi). CONCLUSIONS: The in vitro observation of Th17 cells differentiating into Tregs in NOD mice could raise the hypothesis that the immune regulatory activity of HSPs could be an efficient strategy for diabetes prevention and treatment.
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Células Presentadoras de Antígenos/efectos de los fármacos , Células Presentadoras de Antígenos/inmunología , Diabetes Mellitus/tratamiento farmacológico , Evaluación Preclínica de Medicamentos/métodos , Linfocitos T Reguladores/efectos de los fármacos , Linfocitos T Reguladores/inmunología , Animales , Células Presentadoras de Antígenos/patología , Bioensayo/métodos , Células Cultivadas , Técnicas de Cocultivo/métodos , Diabetes Mellitus/patología , Relación Dosis-Respuesta a Droga , Femenino , Hipoglucemiantes/administración & dosificación , Factores Inmunológicos/administración & dosificación , Ratones , Ratones Endogámicos BALB C , Ratones Endogámicos NOD , Evaluación de Resultado en la Atención de Salud/métodos , Linfocitos T Reguladores/patologíaRESUMEN
The monitoring of the content of polycyclic aromatic hydrocarbons (PAHs) is important for evaluating heavy oil products, especially those most likely to cause environmental impacts. In this study, a comparison between samples of heavy petroleum fractions, using different methods, was carried out. The calculation of carbon distribution and polycyclic aromatic contents was compared with other methods using Fourier transform infrared spectroscopy (FTIR). Therefore, it was possible to quickly estimate the aromatic content by the FTIR method, and the results showed consistency with those obtained through traditional methods. A rapid method, using extraction with dimethyl sulfoxide followed by FTIR measurements, was proposed and shown as particularly useful and reliable for a quick quantification of the PAH content, when compared to the traditional IP 346 method. Furthermore, the difference in total aromatic and PAH concentrations may be more clearly established. This rapid method may be used for the evaluation of PAH content in samples obtained from studies for their removal from complex heavy oil fractions.
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Monitoreo del Ambiente/métodos , Petróleo/análisis , Hidrocarburos Policíclicos Aromáticos/análisis , Carbono , Aceites/químicaRESUMEN
Background: farming of hybrid catfish is relatively recent in Brazil; consequently, it is necessary to develop practical diet formulations for this fish. Objective: to evaluate the influence of different carbohydrate/lipid ratios (CHO:L) on growth performance, body composition and nutrient utilization of hybrid catfish (Pseudoplatystoma reticulatum x Leiarius marmoratus). Methods: four isonitrogenous diets were formulated with increasing lipid levels, using the following CHO:L ratios: 1.3:1 (diet 1); 1.1:1 (diet 2); 0.9:1 (diet 3), and 0.8:1 (diet 4). Fish were fed 5% of BW/day (dry-weight basis) in triplicate groups of 6 fish each (18 ± 1.5 g) for 2 months. Results: though final weight and absolute weight gain decreased with increasing dietary lipid (p<0.05), there was no significant difference in daily feed consumption among treatments (p>0.05). Moreover, viscerosomatic index and hepatosomatic index showed no statistical difference among dietary treatments. Body lipid increase for fish fed diet 4. Lipid and energy efficiency retentions were higher at 0.8:1 CHO:L group. Conclusion: CHO:L ratios around 1.3:1 produced large benefit by best growth performance in the studied hybrid model.
Antecedentes: el cultivo del bagre híbrido es relativamente reciente en Brasil, con lo cual se hace necesario desarrollar dietas prácticas para este pez. Objetivo: evaluar la influencia de la relación carbohidratos/ lípidos (CHO:L) en el crecimiento, composición corporal, y utilización de nutrientes por el bagre híbrido (Pseudoplatystoma reticulatum x Leiarius marmoratus). Métodos: cuatro dietas isonitrogenadas fueron formuladas con niveles incrementales de lípidos, utilizando la siguiente relación CHO/L: 1,3:1 (dieta 1); 1,1:1 (dieta 2); 0,9:1 (dieta 3), y 0,8:1 (dieta 4). Los peces fueron alimentados con 5% de BW/día (en base a peso seco), en triplicado con 6 peces/grupo (18 ± 1,5 g) por grupo, por un tiempo de 2 meses. Resultados: aunque el peso final y la ganancia de peso absoluto disminuyó con el aumento de lípidos en la dieta (p<0,05), no hubo diferencia significativa en el consumo diario de alimento entre los tratamientos (p>0,05). Por otra parte, para el índice viscerosomático e índice hepatosomático no hubo diferencias estadísticas entre los tratamientos. Se ha observado el aumento de los lípidos corporales de peces alimentados con la dieta 4. La eficiencia de retención de lípidos y energética fueron mayores en el grupo 0,8:1 CHO:L. Conclusión: la relación CHO:L alrededor de 1,3:1 produce un gran beneficio al mejorar el crecimiento del modelo del pez híbrido estudiado.
Antecedentes: o cultivo de bagre híbrido com características favoráveis ao crescimento é relativamente recente no Brasil, consequentemente é necessária a formulação de dietas práticas para essa espécie. Objetivo: se avaliou a influência da relação carboidrato/lipídio (CHO:L) no crescimento, composição corporal e utilização de nutrientes pelo bagre híbrido (Pseudoplatystoma reticulatum x Leiarius marmoratus). Métodos: quatro dietas isonitrogenadas foram formuladas com o aumento dos níveis de lipídios na dieta, utilizando a seguinte relação CHO/L: 1,3:1 (dieta 1); 1,1:1 (dieta 2); 0,9:1 (dieta 3), y 0,8:1 (dieta 4). Os peixes foram alimentados a 5% de BW/dia (base de peso seco), sendo triplicatas de 6 peixes (18 ± 1,5 g) por grupo por um período de 2 meses. Resultados: apesar do peso final e do ganho de peso absoluto decrescerem com o aumento da dieta lipídica (p<0,05), não houve diferença significativa no consumo diário de alimento entre os tratamentos (p>0,05). Contudo, os índices viscerossomático e hepatossomático não demonstraram diferença estatística entre os tratamentos. Foi registrado aumento dos lipidios corporais para os peixes alimentados com a dieta 4. A eficiência de retenção de lipídios e a eficiência de retenção energética foram maiores para o grupo 0,8 CHO:L. Conclusão: a relação ao redor de 1,3 produziu grandes benefícios por melhorar o crescimento do modelo de peixe híbrido estudado.
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Ottonia martiana is a plant popularly known in Brazil by the use for toothache. Ethanolic extract (EE), hexane fraction (HF), dichloromethane fraction (DF) and piperovatine obtained from O. martiana were assayed in vitro and in vivo. The acute toxicity of EE was determined, and LD50 values of 164.5 and 65.0 mg/kg by the oral and intraperitoneal routes, respectively, indicated a high toxicity for EE in vivo, explaining its popular use by topical administration only. A local anesthetic-like effect of EE and its fractions was observed in experimental models using pain induction, and such effect involved an analgesic action. The antimycobacterial activity of EE, HF, DF and piperovatine was evaluated against Mycobacterium tuberculosis H37Rv ATCC 27924. EE, HF, DF, and piperovatine showed a potential antimycobacterial effect with MICs of 16.0, 62.0, 62.0 and 8.0 µg/mL, respectively. Piperovatine was more effective than the EE or the other fractions. The selectivity index (SI=IC50/MIC) values calculated for EE, HF, DF and piperovatine based on the MICs and the cytotoxicity against J774 macrophages (IC50 by MTT assay) revealed values of 6.43, 2.34, 1.5 and 9.66, respectively.
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Analgésicos/farmacología , Antibacterianos/farmacología , Cloruro de Metileno/farmacología , Piperaceae/química , Extractos Vegetales/farmacología , Ácido Sórbico/análogos & derivados , Analgésicos/toxicidad , Animales , Antibacterianos/toxicidad , Cobayas , Dosificación Letal Mediana , Cloruro de Metileno/toxicidad , Ratones , Pruebas de Sensibilidad Microbiana , Extractos Vegetales/química , Extractos Vegetales/toxicidad , Conejos , Ácido Sórbico/farmacología , Ácido Sórbico/toxicidadRESUMEN
OBJECTIVES: Although TB immunotherapy improves the results of conventional drug treatment, the effects of combining chemotherapy and immunotherapy have never been systematically evaluated. We used a comprehensive lung transcriptome analysis to directly compare the activity of combined chemotherapy and immunotherapy with that of single treatments in a mouse model of TB. METHODS: Mycobacterium tuberculosis-infected mice in the chronic phase of the disease (day 30) received: (i) isoniazid and rifampicin (drugs) daily for 30 days; (ii) DNA immunotherapy (DNA), consisting of four 100 µg injections at 10 day intervals; (iii) both therapies (DNAâ+âdrugs); or (iv) saline. The effects were evaluated 10 days after the end of treatment (day 70 post-infection). RESULTS: In all groups a systemic reduction in the load of bacilli was observed, bacilli became undetectable in the drugs and DNAâ+âdrugs groups, but the whole lung transcriptome analysis showed 867 genes exclusively modulated by the DNAâ+âdrugs combination. Gene enrichment analysis indicated that DNAâ+âdrugs treatment provided synergistic effects, including the down-regulation of proinflammatory cytokines and mediators of fibrosis, as confirmed by real-time PCR, ELISA, histopathology and hydroxyproline assay. CONCLUSIONS: Our results provide a molecular basis for the advantages of TB treatment using combined chemotherapy and DNA immunotherapy and demonstrate the synergistic effects obtained with this strategy.
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Terapia Combinada/métodos , Quimioterapia/métodos , Inmunoterapia/métodos , Mycobacterium tuberculosis/efectos de los fármacos , Mycobacterium tuberculosis/inmunología , Tuberculosis/terapia , Animales , Antituberculosos/administración & dosificación , Modelos Animales de Enfermedad , Perfilación de la Expresión Génica , Isoniazida/administración & dosificación , Pulmón/microbiología , Pulmón/patología , Ratones Endogámicos BALB C , Rifampin/administración & dosificación , Resultado del Tratamiento , Vacunas de ADN/administración & dosificaciónRESUMEN
BACKGROUND: Phospholipases C (PLCs) are virulence factors found in several bacteria. In Mycobacterium tuberculosis (Mtb) they exhibit cytotoxic effects on macrophages, but the mechanisms involved in PLC-induced cell death are not fully understood. It has been reported that induction of cell necrosis by virulent Mtb is coordinated by subversion of PGE2, an essential factor in cell membrane protection. RESULTS: Using two Mtb clinical isolates carrying genetic variations in PLC genes, we show that the isolate 97-1505, which bears plcA and plcB genes, is more resistant to alveolar macrophage microbicidal activity than the isolate 97-1200, which has all PLC genes deleted. The isolate 97-1505 also induced higher rates of alveolar macrophage necrosis, and likewise inhibited COX-2 expression and PGE2 production. To address the direct effect of mycobacterial PLC on cell necrosis and PGE2 inhibition, both isolates were treated with PLC inhibitors prior to macrophage infection. Interestingly, inhibition of PLCs affected the ability of the isolate 97-1505 to induce necrosis, leading to cell death rates similar to those induced by the isolate 97-1200. Finally, PGE2 production by Mtb 97-1505-infected macrophages was restored to levels similar to those produced by 97-1200-infected cells. CONCLUSIONS: Mycobacterium tuberculosis bearing PLCs genes induces alveolar macrophage necrosis, which is associated to subversion of PGE2 production.
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Muerte Celular , Dinoprostona/antagonistas & inhibidores , Macrófagos Alveolares/microbiología , Macrófagos Alveolares/fisiología , Mycobacterium tuberculosis/enzimología , Fosfolipasas de Tipo C/metabolismo , Factores de Virulencia/metabolismo , Proteínas Bacterianas/genética , Humanos , Mycobacterium tuberculosis/inmunología , Mycobacterium tuberculosis/aislamiento & purificación , Tuberculosis/microbiología , Fosfolipasas de Tipo C/genéticaRESUMEN
Despite substantial efforts in recent years toward the development of new vaccines and drugs against tuberculosis (TB), success has remained elusive. Immunotherapy of TB with mycobacterial Hsp65 as a DNA vaccine (DNA-hsp65) results in a reduction of systemic bacterial loads and lung tissue damage, but the high homology of Hsp65 with the mammalian protein raises concern that pathological autoimmune responses may also be triggered. We searched for autoimmune responses elicited by DNA-hsp65 immunotherapy in mice chronically infected with TB by evaluating the humoral immune response and comprehensive histopathology using stereology. Cross-reactive antibodies between mycobacterial and mammalian Hsp60/65 were detected; however, no signs of pathological autoimmunity were found up to 60 days after the end of the therapy.
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Anticuerpos Antibacterianos/inmunología , Autoinmunidad/inmunología , Proteínas Bacterianas/inmunología , Chaperonina 60/inmunología , Proteínas Mitocondriales/inmunología , Mycobacterium leprae/inmunología , Vacunas de ADN/inmunología , Animales , Autoinmunidad/efectos de los fármacos , Proteínas Bacterianas/administración & dosificación , Chaperonina 60/administración & dosificación , Chaperonina 60/antagonistas & inhibidores , Reacciones Cruzadas/efectos de los fármacos , Reacciones Cruzadas/inmunología , Inmunidad Humoral/efectos de los fármacos , Inmunidad Humoral/inmunología , Inmunoterapia/métodos , Ratones , Ratones Endogámicos BALB C , Proteínas Mitocondriales/antagonistas & inhibidores , Vacunas contra la Tuberculosis/administración & dosificación , Vacunas contra la Tuberculosis/inmunología , Vacunas de ADN/administración & dosificaciónRESUMEN
Tuberculosis (TB) is a serious public health problem. Development of experimental models and vaccines are essential to elucidate physiopathological mechanisms and to control the disease. Vascular endothelial growth factor (VEGF) is a potent activator of vascular permeability and angiogenesis. VEGF seems to participate in breakdown of the blood brain-barrier (BBB) in tuberculous meningitis (TBM), contributing to worsening of disease. Therefore, the objective here was to extent the characterization of our previously described murine model of central nervous system TB (CNS-TB) by describing the VEGF participation in the CNS disease, and suggesting a vaccination plan in mice. Plasmid encoding DNA protein antigen DNA-hsp65 has been described as a protector against TB infection and was used here to test its effectiveness in the prevention of VEGF production and TB disease. Vaccinated mice and its controls were injected with Mycobacterium bovis bacillus Calmette-Guerin (BCG) in cerebellum. Four weeks after BCG injection, mice were perfused and brains were paraffin-embedded for VEGF expression analysis. We observed VEGF immunohistochemical expression in TBM and granulomas in non-vaccinated mice. The DNA-hsp65 treatment blocked the expression of VEGF in mice TBM. Therefore, our murine model indicated the VEGF participation in the physiopathology of CNS-TB and the potential prevention of the DNA-hsp65 in the disease progression.
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Proteínas Bacterianas/inmunología , Chaperonina 60/inmunología , Vacunas contra la Tuberculosis/inmunología , Tuberculosis del Sistema Nervioso Central/metabolismo , Vacunas de ADN/inmunología , Factor A de Crecimiento Endotelial Vascular/biosíntesis , Animales , Proteínas Bacterianas/genética , Enfermedades Cerebelosas/metabolismo , Enfermedades Cerebelosas/prevención & control , Cerebelo/metabolismo , Chaperonina 60/genética , Modelos Animales de Enfermedad , Esquemas de Inmunización , Masculino , Ratones , Mycobacterium bovis , Tuberculoma Intracraneal/metabolismo , Tuberculoma Intracraneal/prevención & control , Tuberculosis del Sistema Nervioso Central/prevención & control , Tuberculosis Meníngea/metabolismo , Tuberculosis Meníngea/prevención & controlRESUMEN
Despite the enormous efforts displayed globally in the fight against tuberculosis, the disease incidence has modified slightly, which has led to a renewed interest in immunotherapy. In general, successful immunotherapeutic candidates against tuberculosis are agents that can trigger strong, specific pro-inflammatory responses, especially of the T-helper (Th) 1 pattern. However, how these pro-inflammatory agents effectively kill the bacteria without eliciting immunopathology is not well understood. We reasoned that, in addition to the specific immune response elicited by immunotherapy, the evaluation of the overall pro-inflammatory responses should provide additional and valuable information that will be useful in avoiding immunopathology. We evaluated the overall IFN-γ and IL-17 pro-inflammatory responses among CD4(+), CD8(+) and γδ T cells in the lungs of mice that were infected with M. tuberculosis and treated with a DNA vaccine in an immunotherapeutic regimen. Our results demonstrate that mice that effectively combat the pathogen develop a strong, specific Th1 immune response against the therapeutic antigen and have reduced lung inflammation, present in parallel a fine-tuning in the total IFN-γ- and IL-17-mediated immunity in the lungs. This modulation of the total immune response involves reducing the Th17 cell population, augmenting CD8(+) T cells that produce IFN-γ and increasing the total γδ T cell frequency. These results stress the importance of a broad evaluation of not only the specific immune response at the time to evaluate new immune interventional strategies against tuberculosis but also non-conventional T cells, such as γδ T lymphocytes.
Asunto(s)
Linfocitos T CD4-Positivos/inmunología , Linfocitos T CD8-positivos/inmunología , Terapia Genética/métodos , Inflamación , Interferón gamma/metabolismo , Interleucina-17/metabolismo , Tuberculosis/terapia , Animales , Modelos Animales de Enfermedad , Femenino , Pulmón/inmunología , Pulmón/patología , Ratones , Ratones Endogámicos BALB C , Receptores de Antígenos de Linfocitos T gamma-delta/inmunologíaRESUMEN
BACKGROUND: Although plasmid DNA encoding an antigen from pathogens or tumor cells has been widely studied as vaccine, the use of plasmid vector (without insert) as therapeutic agent requires further investigation. RESULTS: Here, we showed that plasmid DNA (pcDNA3) at low doses inhibits the production of IL-6 and TNF-α by lipopolysaccharide (LPS)-stimulated macrophage cell line J774. These findings led us to evaluate whether plasmid DNA could act as an anti-inflammatory agent in a Wistar rat endotoxemia model. Rats injected simultaneously with 1.5 mg/kg of LPS and 10 or 20 µg of plasmid DNA had a remarkable attenuation of mean arterial blood pressure (MAP) drop at 2 hours after treatment when compared with rats injected with LPS only. The beneficial effect of the plasmid DNA on MAP was associated with decreased expression of IL-6 in liver and increased concentration of plasma vasopressin (AVP), a known vasoconstrictor that has been investigated in hemorrhagic shock management. No difference was observed in relation to nitric oxide (NO) production. CONCLUSION: Our results demonstrate for the first time that plasmid DNA vector at low doses presents anti-inflammatory property and constitutes a novel approach with therapeutic potential in inflammatory diseases.