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1.
Mem Inst Oswaldo Cruz ; 119: e230149, 2024.
Article in English | MEDLINE | ID: mdl-38359306

ABSTRACT

BACKGROUND: American tegumentary leishmaniasis (ATL) is an endemic neglected tropical disease (NTD), its conventional treatment is toxic, slow, and invasive. Rapid diagnosis is crucial for the clinical management of suspected patients, so the development and use of low-cost, miniaturised and portable devices could be the key. OBJECTIVES: This work aimed to develop a simple paper-based electrochemical platform for the serological detection of ATL. METHODS: Platform was fabricated in Whatman N°1 paper, contains a hydrophobic zone generated by wax printing, two pencil graphite electrodes, and uses specific crude extracts (CA) antigens for ATL immuno-determination. The platform performance was analysed by measuring the relative impedance change for different antigen-antibody combinations. Then, 10 serum human samples previously diagnosed by the gold standard (five positive ATL cases and five non-ATL cases) were evaluated. FINDINGS: The platform presented a linear response for the charge transfer resistance (ΔRct) and the interface reactance (ΔXc). Also, optimal working conditions were established (1/60 serum dilution and 180 µg/mL CA concentration). Then, the platform permits to distinguish between ATL and non-ATL (p < 0.05) human serum samples. MAIN CONCLUSIONS: Our platform could allow the diagnosis, management, and monitoring of leishmaniasis while being an extremely simple and environmentally friendly technology.


Subject(s)
Leishmaniasis, Cutaneous , Serologic Tests , Humans , Leishmaniasis, Cutaneous/diagnosis , Serologic Tests/instrumentation
2.
Mem Inst Oswaldo Cruz ; 118: e220263, 2023.
Article in English | MEDLINE | ID: mdl-37222309

ABSTRACT

BACKGROUND: Vaccine development is a laborious craftwork in which at least two main components must be defined: a highly immunogenic antigen and a suitable delivery method. Hence, the interplay of these elements could elicit the required immune response to cope with the targeted pathogen with a long-lasting protective capacity. OBJECTIVES: Here we evaluate the properties of Escherichia coli spherical proteoliposomes - known as outer membrane vesicles (OMVs) - as particles with natural adjuvant capacities and as antigen-carrier structures to assemble an innovative prophylactic vaccine for Chagas disease. METHODS: To achieve this, genetic manipulation was carried out on E. coli using an engineered plasmid containing the Tc24 Trypanosoma cruzi antigen. The goal was to induce the release of OMVs displaying the parasite protein on their surface. FINDINGS: As a proof of principle, we observed that native OMVs - as well as those carrying the T. cruzi antigen - were able to trigger a slight, but functional humoral response at low immunization doses. Of note, compared to the non-immunized group, native OMVs-vaccinated animals survived the lethal challenge and showed minor parasitemia values, suggesting a possible involvement of innate trained immunity mechanism. MAIN CONCLUSION: These results open the range for further research on the design of new carrier strategies focused on innate immunity activation as an additional immunization target and venture to seek for alternative forms in which OMVs could be used for optimizing vaccine development.


Subject(s)
Chagas Disease , Escherichia coli , Animals , Antigens, Protozoan , Immunity, Innate , Parasitemia
3.
Biocell ; 47(8): 1835-1852, 2023 Aug 28.
Article in English | MEDLINE | ID: mdl-37771344

ABSTRACT

Backgorund: Fruits and seed extracts of Annona montana have significant cytotoxic potential in several cancer cells. This study evaluates the effect of A. montana leaves hexane extract on several signaling cascades and gene expression in metastatic breast cancer cells upon insulin-like growth factor-1 (IGF-1) stimulation. Methods: MTT assay was performed to determine the proliferation of cancer cells. Propidium iodide staining and flow cytometry analysis of Annexin V binding was utilized to measure the progression of the cell cycle and the induction of apoptosis. Protein expression and phosphorylation were determined by western blotting analysis to examine the underlying cellular mechanism triggered upon treatment with A. montana leaves hexane extract. Results: A. montana leaves hexane (sub-fraction V) blocked the constitutive stimulation of the PI3K/mTOR signaling pathways. This inhibitory effect was associated with apoptosis induction as evidenced by the positivity with Annexin V and terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNNEL) staining, activation of caspase-3, and cleavage of PPAR. It also limited the expression of various downstream genes that regulate proliferation, survival, metastasis, and angiogenesis (i.e., cyclin D1, survivin, COX-2, and VEGF). It increased the expression of p53 and p21. Interestingly, we also observed that this extract blocked the activation of AKT and ERK without affecting the phosphorylation of the IGF-1 receptor and activation of Ras upon IGF-1 stimulation. Conclusion: Our study indicates that A. montana leaves (sub-fraction V) extract exhibits a selective anti-proliferative and proapoptotic effect on the metastatic MDA-MB-231 breast cancer cells through the involvement of PI3K/AKT/mTOR/S6K1 pathways.

4.
Environ Monit Assess ; 195(11): 1320, 2023 Oct 14.
Article in English | MEDLINE | ID: mdl-37837468

ABSTRACT

This study aims to investigate the presence of SARS-CoV-2 in public spaces and assess the utility of inexpensive air purifiers equipped with high-efficiency particulate air (HEPA) filters for viral detection. Samples were collected from six community-based organizations in underserved minority neighborhoods in Northwest Miami, Florida, from February to May 2022. Reverse transcription-quantitative polymerase chain reaction (RT-qPCR) was used to detect SARS-CoV-2 in air purifier filters and surface swabs. Among 32 filters tested, three yielded positive results, while no positive surface swabs were found. Notably, positive samples were obtained exclusively from child daycare centers. These findings highlight the potential for airborne transmission of SARS-CoV-2 in indoor air, particularly in child daycare centers. Moreover, the study demonstrates the effectiveness of readily available HEPA filters in detecting the virus. Improving indoor ventilation and implementing air filtration systems are crucial in reducing COVID-19 transmission where people gather. Air filtration systems incorporating HEPA filters offer a valuable approach to virus detection and reducing transmission risks. Future research should explore the applicability of this technology for early identification and mitigation of viral outbreaks.


Subject(s)
Air Filters , Air Pollution, Indoor , COVID-19 , Child , Humans , SARS-CoV-2 , Air Pollution, Indoor/analysis , Environmental Monitoring , Dust/analysis
5.
AIDS Behav ; 25(11): 3658-3668, 2021 Nov.
Article in English | MEDLINE | ID: mdl-34009479

ABSTRACT

We evaluated mental health and substance use during the COVID-19 pandemic in 196 participants from the Miami Adult Studies on HIV (MASH) Cohort. A survey was administered between July-August of 2020, including validated measures of resilience and anxiety, a scale to measure COVID-19-related worry, and self-reported substance use. Compared to HIV-uninfected participants (n = 80), those living with HIV (n = 116) reported fewer anxiety symptoms, less COVID-19-related worry, and higher resilience. Those with more anxiety symptoms and lower resilience engaged in more frequent alcohol consumption, binge drinking, and cocaine use. Alcohol misuse was more common among HIV-uninfected participants. Cocaine use was reported by 21% fewer participants during the pandemic compared with 7.3 ± 1.5 months earlier. Possibly due to their experiences with HIV, PLWH responded with higher resilience and reduced worry and anxiety to the adversities brought by the COVID-19 pandemic.


Subject(s)
COVID-19 , HIV Infections , Substance-Related Disorders , Adult , Anxiety/epidemiology , HIV Infections/epidemiology , HIV Infections/prevention & control , Humans , Pandemics , SARS-CoV-2 , Substance-Related Disorders/epidemiology
6.
Int J Mol Sci ; 23(1)2021 Dec 28.
Article in English | MEDLINE | ID: mdl-35008706

ABSTRACT

Viral infections have afflicted human health and despite great advancements in scientific knowledge and technologies, continue to affect our society today. The current coronavirus (COVID-19) pandemic has put a spotlight on the need to review the evidence on the impact of nutritional strategies to maintain a healthy immune system, particularly in instances where there are limited therapeutic treatments. Selenium, an essential trace element in humans, has a long history of lowering the occurrence and severity of viral infections. Much of the benefits derived from selenium are due to its incorporation into selenocysteine, an important component of proteins known as selenoproteins. Viral infections are associated with an increase in reactive oxygen species and may result in oxidative stress. Studies suggest that selenium deficiency alters immune response and viral infection by increasing oxidative stress and the rate of mutations in the viral genome, leading to an increase in pathogenicity and damage to the host. This review examines viral infections, including the novel SARS-CoV-2, in the context of selenium, in order to inform potential nutritional strategies to maintain a healthy immune system.


Subject(s)
SARS-CoV-2/immunology , Selenium/immunology , Selenium/pharmacology , Virus Diseases/diet therapy , Virus Diseases/immunology , Animals , Dietary Supplements , Humans , Reactive Oxygen Species/metabolism , SARS-CoV-2/drug effects , Selenium/deficiency , Selenoproteins/physiology
7.
Mem Inst Oswaldo Cruz ; 114: e180571, 2019.
Article in English | MEDLINE | ID: mdl-31116244

ABSTRACT

BACKGROUND: TcP21 is a ubiquitous secreted protein of Trypanosoma cruzi and its recombinant form (rP21) promotes parasite cell invasion and acts as a phagocytosis inducer by activating actin polymerisation in the host cell. OBJECTIVE: Our goal was to evaluate if the additional supplementation of rP21 during a prime/boost/challenge scheme with T. cruzi TCC attenuated parasites could modify the well-known protective behavior conferred by these parasites. METHODS: The humoral immune response was evaluated through the assessment of total anti-T. cruzi antibodies as well as IgG subtypes. IFN-γ, TNF-α and IL-10 were measured in supernatants of splenic cells stimulated with total parasite homogenate or rP21. FINDINGS: Our results demonstrated that, when comparing TCC+rP21 vs. TCC vaccinated animals, the levels of IFN-γ were significantly higher in the former group, while the levels of IL-10 and TNF-α were significantly lower. Further, the measurement of parasite load after lethal challenge showed an exacerbated infection and parasite load in heart and skeletal muscle after pre-treatment with rP21, suggesting the important role of this protein during parasite natural invasion process. MAIN CONCLUSION: Our results demonstrated that rP21 may have adjuvant capacity able to modify the cytokine immune profile elicited by attenuated parasites.


Subject(s)
Antibodies, Protozoan/immunology , Antigens, Protozoan/immunology , Chagas Disease/immunology , Protozoan Proteins/immunology , Trypanosoma cruzi/immunology , Vaccines, Attenuated/immunology , Animals , Chagas Disease/prevention & control , Disease Models, Animal , Immunoglobulin G/blood , Immunoglobulin G/immunology , Interferon-alpha/blood , Interferon-alpha/immunology , Interferon-gamma/blood , Interferon-gamma/immunology , Interleukin-10/blood , Interleukin-10/immunology , Male , Mice , Mice, Inbred C57BL , Phagocytosis , Vaccines, Attenuated/administration & dosage
8.
Glia ; 66(11): 2353-2365, 2018 11.
Article in English | MEDLINE | ID: mdl-30394585

ABSTRACT

When activated, microglial cells have the potential not only to secrete typical proinflammatory mediators but also to release the neurotransmitter glutamate in amounts that may promote excitotoxicity. Here, we wished to determine the potential of the Parkinson's disease (PD) protein α-Synuclein (αS) to stimulate glutamate release using cultures of purified microglial cells. We established that glutamate release was robustly increased when microglial cultures were treated with fibrillary aggregates of αS but not with the native monomeric protein. Promotion of microglial glutamate release by αS aggregates (αSa) required concomitant engagement of TLR2 and P2X7 receptors. Downstream to cell surface receptors, the release process was mediated by activation of a signaling cascade sequentially involving phosphoinositide 3-kinase (PI3K) and NADPH oxidase, a superoxide-producing enzyme. Inhibition of the Xc- antiporter, a plasma membrane exchange system that imports extracellular l-cystine and exports intracellular glutamate, prevented the release of glutamate induced by αSa, indicating that system Xc- was the final effector element in the release process downstream to NADPH oxidase activation. Of interest, the stimulation of glutamate release by αSa was abrogated by dopamine through an antioxidant effect requiring D1 dopamine receptor activation and PI3K inhibition. Altogether, present data suggest that the activation of microglial cells by αSa may possibly result in a toxic build-up of extracellular glutamate contributing to excitotoxic stress in PD. The deficit in dopamine that characterizes this disorder may further aggravate this process in a vicious circle mechanism.


Subject(s)
Dopamine/pharmacology , Glutamic Acid/metabolism , Microglia/drug effects , Protein Aggregates/drug effects , alpha-Synuclein/metabolism , Adenosine Triphosphate/analogs & derivatives , Adenosine Triphosphate/pharmacology , Animals , Animals, Newborn , Antibodies, Monoclonal/pharmacology , Carbon Isotopes/pharmacokinetics , Cells, Cultured , Cystine/pharmacokinetics , Humans , Lipopeptides/pharmacology , Lipopolysaccharides/pharmacology , Mice , Microglia/ultrastructure , Platelet Aggregation Inhibitors/pharmacology , Reactive Oxygen Species/metabolism , Signal Transduction/drug effects , Toll-Like Receptor 2/immunology , alpha-Synuclein/pharmacology
9.
Mol Microbiol ; 105(6): 922-933, 2017 Sep.
Article in English | MEDLINE | ID: mdl-28692133

ABSTRACT

The role of the class IIa bacteriocin membrane receptor protein remains unclear, and the following two different mechanisms have been proposed: the bacteriocin could interact with the receptor changing it to an open conformation or the receptor might act as an anchor allowing subsequent bacteriocin insertion and membrane disruption. Bacteriocin-producing cells synthesize an immunity protein that forms an inactive bacteriocin-receptor-immunity complex. To better understand the molecular mechanism of enterocin CRL35, the peptide was expressed as the suicidal probe EtpM-enterocin CRL35 in Escherichia coli, a naturally insensitive microorganism since it does not express the receptor. When the bacteriocin is anchored to the periplasmic face of the plasma membrane through the bitopic membrane protein, EtpM, E. coli cells depolarize and die. Moreover, co-expression of the immunity protein prevents the deleterious effect of EtpM-enterocin CRL35. The binding and anchoring of the bacteriocin to the membrane has demonstrated to be a sufficient condition for its membrane insertion. The final step of membrane disruption by EtpM-enterocin CRL35 is independent from the receptor, which means that the mannose PTS might not be involved in the pore structure. In addition, the immunity protein can protect even in the absence of the receptor.


Subject(s)
Bacteriocins/metabolism , Escherichia coli/metabolism , Anti-Bacterial Agents/pharmacology , Bacteriocins/immunology , Cell Membrane/metabolism , Escherichia coli/drug effects , Escherichia coli Proteins/metabolism , Listeria , Membrane Potentials/drug effects , Microbial Sensitivity Tests , Peptides/metabolism , Periplasm/metabolism
10.
Vaccines (Basel) ; 12(6)2024 Jun 04.
Article in English | MEDLINE | ID: mdl-38932350

ABSTRACT

Chagas disease, caused by the protozoan Trypanosoma cruzi, remains a major public health challenge affecting millions in Latin America and worldwide. Although significant progress has been made in vector control, no vaccine exists to prevent infection or mitigate disease pathogenesis. We developed a rationally designed chimeric protein vaccine, N-Tc52/TSkb20, incorporating immunodominant epitopes from two T. cruzi antigens, the amino-terminal portion of Tc52 and the TSkb20 epitope derived from trans-sialidase. The objectives of this study were to construct and characterize the antigen and evaluate its protective potential in an immunoprophylactic murine model of T. cruzi infection. The N-Tc52/TSkb20 protein was recombinantly expressed in E. coli and its identity was confirmed using mass spectrometry and Western blotting. Immunization with the chimeric protein significantly controlled parasitemia and reduced the heart, colon, and skeletal muscle parasite burdens compared to non-vaccinated mice. Protection was superior to vaccination with the individual parental antigen components. Mechanistically, the vaccine induced potent CD8+ T-cell and IFNγ responses against the incorporated epitopes and a protective IgG antibody profile. A relatively low IL-10 response favored early parasite control. These results validate the promising multi-epitope approach and support the continued development of this type of rational vaccine design strategy against Chagas disease.

11.
Environ Sci Pollut Res Int ; 30(43): 97377-97385, 2023 Sep.
Article in English | MEDLINE | ID: mdl-37592068

ABSTRACT

Vineyard-derived pomace is a byproduct of the wine industry that can have a negative impact on the environment if it is only disposed of or used as a fertilizer. Owing to its polyphenol content, grape pomace is an alternative to biocontrol undesirable microorganisms. In the present study, we characterized the phenolic composition of red and white grape pomace from Valles Calchaquíes, Argentina, and explored its activity against Leishmania (Leishmania) amazonensis, an etiological agent of American tegumentary leishmaniasis, a neglected endemic disease in northern Argentina. Red and white pomace extracts similarly reduced Leishmania viability after a 48-h treatment, with the fractions containing a higher proportion of phenolic compounds being more active. Both extracts stimulated ATPase activity on the parasite plasma membranes, with white grape pomace having a stronger effect than red grape pomace. In addition, the extracts displayed fairly good anticholinesterase activity, which may have contributed to their anti-Leishmania activity. These results reinforce the potential applicability of grape pomace as an antimicrobial agent for the development of biopesticides.


Subject(s)
Leishmania , Leishmaniasis, Cutaneous , Humans , Argentina , Farms , Phenols , Plant Extracts
12.
Int J Food Microbiol ; 352: 109267, 2021 Aug 16.
Article in English | MEDLINE | ID: mdl-34102464

ABSTRACT

The use of bacteriocins is a promising alternative to improve food security through the biocontrol of food pathogens and spoilage microorganisms. Gram-negative produced microcin J25(G12Y), known as (MccJ25(G12Y)) is a variant of the well-studied and characterized antimicrobial peptide, microcin J25 (MccJ25). In the present work, we explored the activity of this microcin against Gram-negative bacteria linked to foodborne diseases. We evaluated the in vitro antimicrobial activity of MccJ25(G12Y) in solid medium against a collection of pathogenic and food-altering strains and studied its activity and stability in meat and dairy food systems. We show that MccJ25(G12Y) exhibited the same in vitro antimicrobial spectrum as its parental microcin (MccJ25) against different Gram-negative foodborne pathogens and spoilage strains. We highlight that low concentrations of MccJ25(G12Y) between 0.45 and 29.4 µM were able to inhibit a substantial number of pathogens, including Salmonella, Escherichia, Shigella and Enterobacter genus. We also demonstrate the antimicrobial effectiveness of the peptide against Escherichia coli O157:H7 NCTC 12900, Enterobacter cloacae CECT 194, and Salmonella enterica CECT 4396 in fish and beef burgers and yogurt. MccJ25(G12Y) was added or not to food matrices inoculated with the foodborne pathogens at 105 CFU/g or mL. Afterward, food products were stored at 4 °C and selective media for the specific enumeration were used to determine the antimicrobial susceptibility of each pathogen to MccJ25(G12Y). The viability of the three pathogens was significantly reduced in the different food biological environments. In yogurt, the peptide decreased E. coli numbers on day 5 by about 4 log 10 CFU/mL as compared to non-treated samples. For S. enterica and E. cloacae no viable cells were detected at the end of the treatment. Adding MccJ25(G12Y) to fish burgers decreased E. cloacae numbers during storage 2 log10 CFU/g on the first day, reaching a difference of about 5 log 10 CFU/g after 10 days compared to non-treated control. Finally, the peptide decreased E. coli O157:H7 numbers on the beef burgers samples during storage on day 10 by about 3 log 10 CFU/g as compared to non-treated samples. The stability analysis demonstrated that MccJ25(G12Y) is capable of remaining active in these food matrices for a considerable time during the storage at refrigeration temperatures. These results reinforce the studies on the potential applicability of this microcin as a biopreservative in the food industry.


Subject(s)
Bacteriocins/pharmacology , Food Handling/methods , Food Microbiology , Gram-Negative Bacteria/drug effects , Animals , Anti-Bacterial Agents/pharmacology , Colony Count, Microbial , Escherichia coli O157/drug effects , Foodborne Diseases/microbiology , Foodborne Diseases/prevention & control , Salmonella/drug effects
13.
PLoS One ; 15(5): e0232829, 2020.
Article in English | MEDLINE | ID: mdl-32379842

ABSTRACT

The diagnosis of American tegumentary leishmaniasis (ATL) still requires the design of more effective tools. Leishmania (Viannia) braziliensis is the causal agent of the 90% of Argentinean ATL cases. Considering the current knowledge, an ELISA based crude antigen (CA) for the diagnosis was designed. Ninety-nine subjects diagnosed as ATL, 27 as no-ATL, and 84 donors from non-ATL-endemic areas were included in this study. The current ATL diagnosis was based four techniques, dermal smear microscopic examination (parasitological test), PCR, Leishmanin skin test, and clinical records. We obtained CA extracts from promastigotes and amastigotes from macrophage cultures of different zymodemes of endemic Leishmania species circulating in the study area. Crude antigens from the 'local' main zymodeme of L. (V.) braziliensis showed the highest reactivity against anti-Leishmania antibodies compared to the other included species. The CA of amastigotes of this zymodeme was 3.4 fold more reactive than promastigotes one. Moreover, amastigote-membrane CA (MCA) were 3.6 fold more reactive than the soluble antigens. The MCA-ELISA reached a sensitivity and specificity of 98% (CI = 94.7%-100%) and 63.6% (53.9-73.1), respectively. When anti-Trypanosoma cruzi reactive sera were excluded, the specificity reached 98.4% (94.4-100), while the sensitivity was similar, with a positive predictive value (PV) of 98.6% (94.6-100) and negative PV of 96.3% (91.6-100). The performance of the MCA-ELISA results strongly contribute to the final diagnostic decision, since a non-reactive serological result almost discards the suspected ATL, because of its high negative PV. The developed MCA-ELISA showed a high diagnostic performance, which makes it a good candidate for ATL diagnosis, for seroprevalence studies, or for monitoring treatments efficacy.


Subject(s)
Antibodies, Protozoan/blood , Antigens, Protozoan/immunology , Cell Membrane/immunology , Enzyme-Linked Immunosorbent Assay/methods , Leishmania braziliensis/immunology , Leishmaniasis, Cutaneous/diagnosis , Antibody Affinity , Antibody Specificity , Argentina/epidemiology , Blood Donors , Endemic Diseases , Humans , Leishmania braziliensis/growth & development , Leishmaniasis, Cutaneous/blood , Leishmaniasis, Cutaneous/epidemiology , Leishmaniasis, Cutaneous/parasitology , Leishmaniasis, Mucocutaneous/blood , Leishmaniasis, Mucocutaneous/diagnosis , Leishmaniasis, Mucocutaneous/parasitology , Predictive Value of Tests , Sensitivity and Specificity , Seroepidemiologic Studies , Trypanosoma cruzi/immunology
14.
Mem. Inst. Oswaldo Cruz ; 119: e230149, 2024. tab, graf
Article in English | LILACS-Express | LILACS | ID: biblio-1534934

ABSTRACT

BACKGROUND American tegumentary leishmaniasis (ATL) is an endemic neglected tropical disease (NTD), its conventional treatment is toxic, slow, and invasive. Rapid diagnosis is crucial for the clinical management of suspected patients, so the development and use of low-cost, miniaturised and portable devices could be the key. OBJECTIVES This work aimed to develop a simple paper-based electrochemical platform for the serological detection of ATL. METHODS Platform was fabricated in Whatman N°1 paper, contains a hydrophobic zone generated by wax printing, two pencil graphite electrodes, and uses specific crude extracts (CA) antigens for ATL immuno-determination. The platform performance was analysed by measuring the relative impedance change for different antigen-antibody combinations. Then, 10 serum human samples previously diagnosed by the gold standard (five positive ATL cases and five non-ATL cases) were evaluated. FINDINGS The platform presented a linear response for the charge transfer resistance (ΔRct) and the interface reactance (ΔXc). Also, optimal working conditions were established (1/60 serum dilution and 180 µg/mL CA concentration). Then, the platform permits to distinguish between ATL and non-ATL (p < 0.05) human serum samples. MAIN CONCLUSIONS Our platform could allow the diagnosis, management, and monitoring of leishmaniasis while being an extremely simple and environmentally friendly technology.

15.
Cells ; 8(8)2019 07 25.
Article in English | MEDLINE | ID: mdl-31349736

ABSTRACT

: Aggregated forms of the synaptic protein α-synuclein (αS) have been proposed to operate as a molecular trigger for microglial inflammatory processes and neurodegeneration in Parkinson´s disease. Here, we used brain microglial cell cultures activated by fibrillary forms of recombinant human αS to assess the anti-inflammatory and neuroprotective activities of the antibiotic rifampicin (Rif) and its autoxidation product rifampicin quinone (RifQ). Pretreatments with Rif and RifQ reduced the secretion of prototypical inflammatory cytokines (TNF-, IL-6) and the burst of oxidative stress in microglial cells activated with αS fibrillary aggregates. Note, however, that RifQ was constantly more efficacious than its parent compound in reducing microglial activation. We also established that the suppressive effects of Rif and RifQ on cytokine release was probably due to inhibition of both PI3K- and non-PI3K-dependent signaling events. The control of oxidative stress appeared, however, essentially dependent on PI3K inhibition. Of interest, we also showed that RifQ was more efficient than Rif in protecting neuronal cells from toxic factors secreted by microglia activated by αS fibrils. Overall, data with RifQ are promising enough to justify further studies to confirm the potential of this compound as an anti-parkinsionian drug.


Subject(s)
Microglia/drug effects , Microglia/metabolism , Neurodegenerative Diseases/etiology , Neurodegenerative Diseases/metabolism , Rifampin/analogs & derivatives , Rifampin/pharmacology , alpha-Synuclein/metabolism , Cytokines/metabolism , Humans , Inflammation Mediators/metabolism , Models, Biological , Molecular Structure , Neurodegenerative Diseases/pathology , Neurons/drug effects , Neurons/metabolism , Phosphatidylinositol 3-Kinases/metabolism , Receptors, Purinergic P2X7/metabolism , Signal Transduction/drug effects , Toll-Like Receptor 2/metabolism
16.
Rev. colomb. cir ; 38(2): 357-362, 20230303. fig
Article in Spanish | LILACS | ID: biblio-1425216

ABSTRACT

Introducción. Los tumores glómicos provienen de los cuerpos glómicos, que son estructuras con función de termorregulación y se encuentran distribuidas por todo el cuerpo humano, principalmente a nivel distal de las extremidades, donde es común encontrar lesiones características, aunque hay reportes de casos que se presentaron como neoformación en localizaciones más inusuales. Su etiología aun es desconocida. No se sospechan en muchos pacientes y el diagnostico se realiza de manera incidental, por estudios imagenológicos o anatomopatológicos. Caso clínico. Paciente femenina de 66 años, con presencia de tumor glómico en vía aérea, diagnosticado por histopatología e inmunohistoquímica, que fue sometido a resección quirúrgica, con buena evolución posterior. Discusión. Esta presentación atípica de tumor glómico en vía aérea se manifiesta principalmente con síntomas y signos relacionados con obstrucción de la vía aérea. El manejo oportuno es primordial y el diagnóstico definitivo es por histopatología e inmunohistoquímica, donde se observan las características de las células glómicas, estructuras vasculares, músculo liso y la positividad en la inmunotinción de marcadores como actina del músculo liso, CD34, y actina específica del músculo, entre otras. Conclusión. Los tumores glómicos son neoformaciones benignas raras, con presentación más común en zonas distales. Su aparición depende de factores intrínsecos y extrínsecos de los pacientes. Su tasa de recidiva es muy baja en comparación de otros tumores


Introduction. Glomus tumors originate from glomus bodies, which are structures with thermoregulatory function and are distributed throughout the human body, mainly at the distal level of the extremities where it is common to find these characteristic lesions. Although, there are case reports of neoformation presentations with more unusual locations. Their etiology is still unknown. Many times when there is evidence of lesions in atypical areas they are not suspected in many patients and the diagnosis is made incidentally by imaging and/or anatomopathological studies. Clinical case. A 66-year-old female patient with the presence of a glomus tumor in the airway diagnosed by histopathology and immunohistochemistry, underwent surgical resection and presented good evolution after surgery. Discussion. This atypical presentation of glomus tumor in the airway presents mainly with symptoms and signs related to airway obstruction. Timely management is paramount in these patients, and the definitive diagnosis is by histopathology and immunohistochemistry where the presence of the characteristics of glomus cells, vascular structures, smooth muscle and immunostaining positivity towards some markers such as smooth muscle actin, CD34, muscle specific actin, among others, are seen. Conclusion. This type of tumors are rare benign neoformations, with common presentations in distal areas. Their appearance depends on intrinsic and extrinsic factors of the patients and their recurrence rate is very low compared to other tumors


Subject(s)
Humans , Tracheal Neoplasms , Immunohistochemistry , Glomus Tumor , Trachea , Biopsy , Airway Management
17.
Prog Neurobiol ; 162: 17-36, 2018 03.
Article in English | MEDLINE | ID: mdl-29241812

ABSTRACT

Neurodegenerative diseases are chronic and progressive disorders that affect specific regions of the brain, causing gradual disability and suffering that results in a complete inability of patients to perform daily functions. Amyloid aggregation of specific proteins is the most common biological event that is responsible for neuronal death and neurodegeneration in various neurodegenerative diseases. Therapeutic agents capable of interfering with the abnormal aggregation are required, but traditional drug discovery has fallen short. The exploration of new uses for approved drugs provides a useful alternative to fill the gap between the increasing incidence of neurodegenerative diseases and the long-term assessment of classical drug discovery technologies. Drug re-profiling is currently the quickest possible transition from bench to bedside. In this way, experimental evidence shows that some antibiotic compounds exert neuroprotective action through anti-aggregating activity on disease-associated proteins. The finding that many antibiotics can cross the blood-brain barrier and have been used for several decades without serious toxic effects makes them excellent candidates for therapeutic switching towards neurological disorders. The present review is, to our knowledge, the first extensive evaluation and analysis of the anti-amyloidogenic effect of different antibiotics on well-known disease-associated proteins. In addition, we propose a common structural signature derived from the antiaggregant antibiotic molecules that could be relevant to rational drug discovery.


Subject(s)
Amyloid beta-Peptides/drug effects , Anti-Bacterial Agents/pharmacology , Drug Repositioning , Neurodegenerative Diseases/drug therapy , Neuroprotective Agents/pharmacology , Humans
18.
Mem. Inst. Oswaldo Cruz ; 118: e220263, 2023. graf
Article in English | LILACS-Express | LILACS | ID: biblio-1440673

ABSTRACT

BACKGROUND Vaccine development is a laborious craftwork in which at least two main components must be defined: a highly immunogenic antigen and a suitable delivery method. Hence, the interplay of these elements could elicit the required immune response to cope with the targeted pathogen with a long-lasting protective capacity. OBJECTIVES Here we evaluate the properties of Escherichia coli spherical proteoliposomes - known as outer membrane vesicles (OMVs) - as particles with natural adjuvant capacities and as antigen-carrier structures to assemble an innovative prophylactic vaccine for Chagas disease. METHODS To achieve this, genetic manipulation was carried out on E. coli using an engineered plasmid containing the Tc24 Trypanosoma cruzi antigen. The goal was to induce the release of OMVs displaying the parasite protein on their surface. FINDINGS As a proof of principle, we observed that native OMVs - as well as those carrying the T. cruzi antigen - were able to trigger a slight, but functional humoral response at low immunization doses. Of note, compared to the non-immunized group, native OMVs-vaccinated animals survived the lethal challenge and showed minor parasitemia values, suggesting a possible involvement of innate trained immunity mechanism. MAIN CONCLUSION These results open the range for further research on the design of new carrier strategies focused on innate immunity activation as an additional immunization target and venture to seek for alternative forms in which OMVs could be used for optimizing vaccine development.

19.
Rev. colomb. cir ; 37(3): 408-416, junio 14, 2022. tab
Article in Spanish | LILACS | ID: biblio-1378695

ABSTRACT

Introducción. A nivel mundial el cáncer colorrectal es la tercera causa de malignidad y la segunda causa de mortalidad por cáncer. En Colombia, tiene una prevalencia de 8,3 % dentro de las patologías neoplásicas, ubicándolo en el tercer lugar, después del cáncer de próstata y de mama, lo que lo cataloga como un problema de salud pública, por lo que es de gran importancia mantener datos actualizados acerca de su perfil epidemiológico. Métodos. Se realizó un estudio transversal en pacientes con cáncer colorrectal atendidos en el Hospital Universitario del Caribe, Cartagena, Colombia, durante el periodo 2015-2019. Se analizaron las variables sociodemográficas, clínicas, patológicas e histológicas. Resultados. Se encontraron un total de 268 pacientes atendidos por cáncer colorrectal, con predominio femenino en el (54,5 %) de los casos, y edad promedio de 62 años; con comorbilidades en 48,8 % y sintomatología de dolor abdominal en 56,7 %. El adenocarcinoma se encontró en el 82,1 % de los casos y la intervención más realizada fue la hemicolectomía derecha. Conclusión. El perfil epidemiológico del cáncer colorrectal encontrado en este estudio concuerda con los hallazgos de la literatura médica mundial, comprometiendo especialmente mujeres en nuestra institución.


Introduction. Worldwide, colorectal cancer is the third leading cause of malignancy and the second leading cause of cancer mortality. In Colombia, it has a prevalence of 8.3% within neoplastic pathologies, placing it in third place, after prostate and breast cancer, which classifies it as a public health problem, making it of great importance to maintain up-to-date data on its epidemiological profile. Methods. A cross-sectional study was carried out in patients with colorectal cancer treated at the Hospital Universitario del Caribe, Cartagena, Colombia, during the period 2015-2019. Sociodemographic, clinical, pathological and histological variables were analyzed. Results. A total of 268 patients treated for colorectal cancer were found, with a female predominance of 54.5% and an average age of 62 years; comorbidities in 48.8%, and symptoms of abdominal pain in 56.7%. Adenocarcinoma was found in 82.1% of cases and the most performed intervention was right hemicolectomy. Conclusion. The epidemiological profile of colorectal cancer found in this study is consistent with the findings of the world medical literature, especially involving women in our institution.


Subject(s)
Humans , Colon , Neoplasms , Rectum , Adenocarcinoma , Epidemiology
20.
Neurotox Res ; 29(4): 447-59, 2016 May.
Article in English | MEDLINE | ID: mdl-26745968

ABSTRACT

In neurodegenerative diseases, the inflammatory response is mediated by activated glial cells, mainly microglia, which are the resident immune cells of the central nervous system. Activated microglial cells release proinflammatory mediators and neurotoxic factors that are suspected to cause or exacerbate these diseases. We recently demonstrated that doxycycline protects substantia nigra dopaminergic neurons in an animal model of Parkinson's disease. This effect was associated with a reduction of microglial cell activation, which suggests that doxycycline may operate primarily as an anti-inflammatory drug. In the present study, we assessed the anti-inflammatory potential of doxycycline using lipopolysaccharide (LPS)-activated primary microglial cells in culture as a model of neuroinflammation. Doxycycline attenuated the expression of key activation markers in LPS-treated microglial cultures in a concentration-dependent manner. More specifically, doxycycline treatment lowered the expression of the microglial activation marker IBA-1 as well as the production of ROS, NO, and proinflammatory cytokines (TNF-α and IL-1ß). In primary microglial cells, we also found that doxycycline inhibits LPS-induced p38 MAP kinase phosphorylation and NF-kB nuclear translocation. The present results indicate that the effect of doxycycline on LPS-induced microglial activation probably occurs via the modulation of p38 MAP kinase and NF-kB signaling pathways. These results support the idea that doxycycline may be useful in preventing or slowing the progression of PD and other neurodegenerative diseases that exhibit altered glia function.


Subject(s)
Anti-Bacterial Agents/pharmacology , Doxycycline/pharmacology , Microglia/drug effects , NF-kappa B/metabolism , Signal Transduction/drug effects , p38 Mitogen-Activated Protein Kinases/metabolism , Animals , Brain/cytology , Calcium-Binding Proteins/metabolism , Cell Survival/drug effects , Cells, Cultured , Cytokines/metabolism , Drug Interactions , Glial Fibrillary Acidic Protein/metabolism , Lipopolysaccharides/pharmacology , Macrophage-1 Antigen/metabolism , Mice , Microfilament Proteins/metabolism , Nitric Oxide/metabolism , Nuclear Proteins/metabolism , Nucleophosmin , Reactive Oxygen Species/metabolism
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