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1.
Front Immunol ; 15: 1280877, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38533504

RESUMO

Background/Introduction: Adipose tissue (AT) has been highlighted as a promising reservoir of infection for viruses, bacteria and parasites. Among them is Trypanosoma cruzi, which causes Chagas disease. The recommended treatment for the disease in Brazil is Benznidazole (BZ). However, its efficacy may vary according to the stage of the disease, geographical origin, age, immune background of the host and sensitivity of the strains to the drug. In this context, AT may act as an ally for the parasite survival and persistence in the host and a barrier for BZ action. Therefore, we investigated the immunomodulation of T. cruzi-infected human AT in the presence of peripheral blood mononuclear cells (PBMC) where BZ treatment was added. Methods: We performed indirect cultivation between T. cruzi-infected adipocytes, PBMC and the addition of BZ. After 72h of treatment, the supernatant was collected for cytokine, chemokine and adipokine assay. Infected adipocytes were removed to quantify T. cruzi DNA, and PBMC were removed for immunophenotyping. Results: Our findings showed elevated secretion of interleukin (IL)-6, IL-2 and monocyte chemoattractant protein-1 (MCP-1/CCL2) in the AT+PBMC condition compared to the other controls. In contrast, there was a decrease in tumor necrosis factor (TNF) and IL-8/CXCL-8 in the groups with AT. We also found high adipsin secretion in PBMC+AT+T compared to the treated condition (PBMC+AT+T+BZ). Likewise, the expression of CD80+ and HLA-DR+ in CD14+ cells decreased in the presence of T. cruzi. Discussion: Thus, our findings indicate that AT promotes up-regulation of inflammatory products such as IL-6, IL-2, and MCP-1/CCL2. However, adipogenic inducers may have triggered the downregulation of TNF and IL-8/CXCL8 through the peroxisome proliferator agonist gamma (PPAR-g) or receptor expression. On the other hand, the administration of BZ only managed to reduce inflammation in the microenvironment by decreasing adipsin in the infected culture conditions. Therefore, given the findings, we can see that AT is an ally of the parasite in evading the host's immune response and the pharmacological action of BZ.


Assuntos
Doença de Chagas , Nitroimidazóis , Trypanosoma cruzi , Humanos , Interleucina-8 , Leucócitos Mononucleares , Fator D do Complemento , Interleucina-2/uso terapêutico , Tecido Adiposo , Adipócitos , Fator de Necrose Tumoral alfa/uso terapêutico , Imunidade , Falha de Tratamento
2.
Mar Environ Res ; 196: 106422, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38437777

RESUMO

Anthropogenic biodiversity loss poses a significant threat to ecosystem functioning worldwide. Numerically dominant and locally rare (i.e., transient) species are key components of biodiversity, but their contribution to multiple ecosystem functions (i.e., multifunctionality) has been seldomly assessed in marine ecosystems. To fill this gap, here we analyze the effects of a dominant and a transient species on ecosystem multifunctionality. In an observational study conducted along ca. 200 km of the southeastern Pacific coast, the purple mussel Perumytilus purpuratus numerically dominated the mid-intertidal and the dwarf mussel Semimytilus patagonicus exhibited low abundances but higher recruitment rates. In laboratory experiments, the relative abundances of both species were manipulated to simulate the replacement of P. purpuratus by S. patagonicus and five proxies for ecosystem functions-rates of clearance, oxygen consumption, total biodeposit, organic biodeposit, and excretion-were analyzed. This replacement had a positive, linear, and significant effect on the combined ecosystem functions, particularly oxygen consumption and excretion rates. Accordingly, S. patagonicus could well drive ecosystem functioning given favorable environmental conditions for its recovery from rarity. Our study highlights therefore the key role of transient species for ecosystem performance. Improving our understanding of these dynamics is crucial for effective ecosystem conservation, especially in the current scenario of biological extinctions and invasions.


Assuntos
Ecossistema , Mytilidae , Animais , Biodiversidade
3.
Parasite Immunol ; 46(2): e13024, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38385576

RESUMO

Studies involving the immune response in Chagas disease suggest an imbalance in the immune response of symptomatic patients, with an inflammatory profile dominating in Chagas heart disease, mainly by tumour necrosis factor (TNF). TNF is considered a key cytokine in immunopathology in chronic carriers in several processes during the immune response. Our work aimed to evaluate regulatory (interleukin [IL]-4 and IL-10) and inflammatory (TNF, interferon-gamma [IFN-γ], IL-2 and IL-6) cytokines in peripheral blood mononuclear cells culture supernatants. of affected patients with undetermined clinical forms-IND (n = 13) mild heart form-CARD1 (n = 13) and severe cardiac form-CARD2 (n = 16), treated in vitro with two TNF blockers, Adalimumab (ADA) and Etanercept (ETA) alone or in association with Benznidazole (BZ). The results indicate that ADA was more competent in blocking TNF (compared to ETA) in all groups but with much lower levels in the CARD2 group. ETA statistically decreased TNF levels only in the CARD2 group. IFN-γ increased in the CARD2 group after treatment with ETA relative to ADA. IL-4 had its levels decreased when treated by both drugs. IL-2 was detected in cells from CARD2 carriers compared to the NEG group after treatment with both drugs. The association with BZ decreased levels of IL-2/TNF and increased IL-4. These data reinforce the participation of TNF in severe Chagas heart disease and bring perspectives on using these blockers in the immunological treatment of Chagas disease since the use of BZ is extremely limited in these patients.


Assuntos
Doença de Chagas , Cardiopatias , Nitroimidazóis , Humanos , Doença de Chagas/tratamento farmacológico , Citocinas , Cardiopatias/tratamento farmacológico , Cardiopatias/parasitologia , Interferon gama , Interleucina-2 , Interleucina-4 , Leucócitos Mononucleares , Inibidores do Fator de Necrose Tumoral/uso terapêutico , Fator de Necrose Tumoral alfa
4.
Microorganisms ; 12(1)2024 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-38258022

RESUMO

Few studies have evaluated the efficacy of ceftazidime-avibactam (CA) for Klebsiella pneumoniae carbapenemase-producing Enterobacterales bacteremia (KPC-PEB) in high-risk neutropenic patients. This is a prospective multicenter observational study in high-risk neutropenic patients with multi-drug resistant Enterobacterales bacteremia. They were compared according to the resistance mechanism and definitive treatment provided: KPC-CPE treated with CA (G1), KPC-CPE treated with other antibiotics (G2), and patients with ESBL-producing Enterobacterales bacteremia who received appropriate definitive therapy (G3). Thirty-day mortality was evaluated using a logistic regression model, and survival was analyzed with Kaplan-Meier curves. A total of 238 patients were included: 18 (G1), 52 (G2), and 168 (G3). Klebsiella spp. (60.9%) and Escherichia coli (26.4%) were the Enterobacterales most frequently isolated, and 71% of the bacteremias had a clinical source. The resistance profile between G1 and G2 was colistin 35.3% vs. 36.5%, amikacin 16.7% vs. 40.4%, and tigeclycline 11.1% vs. 19.2%. The antibiotics prescribed in combination with G2 were carbapenems, colistin, amikacin, fosfomycin, tigecycline, and fluoroquinolones. Seven-day clinical response in G1 vs. G2 vs. G3 was 94.4% vs. 42.3% vs. 82.7%, respectively (p < 0.001). Thirty-day overall mortality in G1 vs. G2 vs. G3 was 22.2% vs. 53.8% vs. 11.9%, respectively (p < 0.001), and infection-related mortality was 5.5% vs. 51.9% vs. 7.7% (p < 0.001). The independent risk factors for mortality were Pitt score > 4: OR 3.63, 95% CI, 1.18-11.14 (p = 0.025) and KPC-PEB treated with other antibiotics: OR 8.85, 95% CI, 2.58-30.33 (p = 0.001), while 7-day clinical response was a protective factor for survival: OR 0.02, 95% CI, 0.01-0.08 (p < 0.001). High-risk neutropenic patients with KPC-CPE treated with CA had an outcome similar to those treated for ESBL-producing Enterobacterales, with higher 7-day clinical response and lower overall and infection-related mortality than those treated with other antibiotics. In view of these data, CA may be considered the preferred therapeutic option for KPC-PEB in high-risk neutropenic patients.

5.
Chemosphere ; 346: 140630, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37939926

RESUMO

Mercury (Hg) is a globally important pollutant that can negatively impact metabolic, endocrine and immune systems of marine biota. Seabirds are long-lived marine top predators and hence are at risk of bioaccumulating high Hg concentrations from their prey. Here, we measured blood total mercury (THg) concentrations and relationships with physiology and breeding parameters of breeding brown skuas (Stercorarius antarcticus) (n = 49 individuals) at Esperanza/Hope Bay, Antarctic Peninsula. Mean blood THg concentrations were similar in males and females despite the differences in body size and breeding roles, but differed between study years. Immune markers (hematocrit, Immunoglobulin Y [IgY] and albumin) were negatively correlated with blood THg concentrations, which likely indicates a disruptive effect of Hg on immunity. Alanine aminotransferase (GPT) activity, reflecting liver dysfunction, was positively associated with blood THg. Additionally, triacylglycerol and albumin differed between our study years, but did not correlate with Hg levels, and so were more likely to reflect changes in diet and nutritional status rather than Hg contamination. Egg volume correlated negatively with blood THg concentrations. Our study provides new insights into the sublethal effects of Hg contamination on immunity, liver function and breeding parameters in seabirds. In this Antarctic species, exposure to sublethal Hg concentrations reflects the short-term risks which could make individuals more susceptible to environmental stressors, including ongoing climatic changes.


Assuntos
Charadriiformes , Mercúrio , Humanos , Masculino , Animais , Feminino , Aves/metabolismo , Mercúrio/análise , Regiões Antárticas , Monitoramento Ambiental , Charadriiformes/metabolismo , Fígado/metabolismo , Imunocompetência , Albuminas/metabolismo
6.
Rev. chil. infectol ; 40(6)dic. 2023.
Artigo em Espanhol | LILACS-Express | LILACS | ID: biblio-1529997

RESUMO

Introducción: Las infecciones fúngicas invasoras (IFI) en pacientes con neoplasias hematológicas (NH) representan un desafío diagnóstico y terapéutico. Objetivos: Describir la etiología, características clínicas, diagnóstico y evolución de los episodios de IFI probadas y probables en pacientes con NH y trasplante de progenitores hematopoyéticos (TPH). Pacientes y Métodos: Estudio descriptivo, retrospectivo y de cohorte que incluyó IFI probadas y probables en pacientes adultos con NH y TPH. Se realizó seguimiento hasta el día 90. Resultados: Se incluyeron 80 episodios de IFI: 49% probadas y 51% probables, 67,5% por hongos filamentosos (HF), 30% por hongos levaduriformes (HL) y 2,5% por hongos dimorfos. Los tipos de IFI más frecuentes fueron aspergilosis invasoras pulmonares (AP) y candidiasis invasoras (CI), en su mayoría por Candida spp. no albicans. Todos los casos de AP se diagnosticaron por detección de galactomanano en sangre y/o lavado broncoalveolar, y solamente 22,2% presentaban nódulos con halo en la tomografía computada (TC) de tórax, siendo los infiltrados inespecíficos los hallazgos más frecuentes. Tuvieron coinfección bacteriana y viral el 30 y 17,5%, respectivamente. El 50% fueron IFI de brecha, y la mortalidad global y mortalidad relacionada a la IFI fue 51 y 24%, respectivamente. Conclusión: Los HF fueron la principal causa de IFI, con una gran proporción de IFI de brecha, y presentaron elevada mortalidad. Para el diagnóstico, resulta importante la utilización de biomarcadores y jerarquizar cualquier imagen patológica en la TC.


Background: Invasive fungal infections (IFI) in patients with hematological malignancies (HM) represent a diagnostic and therapeutic challenge. Aim: To describe the etiology, clinical characteristics, diagnosis and evolution of proven and probable IFI episodes in patients with HM and hematopoietic stem cell transplantation (HSCT). Methods: Retrospective, descriptive, cohort study performed in adult patients with HM and HSCT, who developed proven and probable IFI. Follow-up was carried out until day 90. Results: A total of 80 IFI episodes were included: 49% proven and 51% probable, 67,5% due to mold (M), 30% to yeast-like fungi (Y) and 2,5% to dimorphic fungi. The most frequent causes were probable pulmonary aspergillosis (PA) and invasive candidiasis (IC), mainly due to non-albicans Candida species. PA were all diagnosed by detection of galactomannan (GM) in blood and bronchoalveolar lavage, and only 22,2% presented halo sign on chest CT. Bacterial and viral coinfections were reported in 30% and 17,5% respectively. Breakthrough IFI occurred in 50%, and global and IFI-related mortality were 51% and 24% respectively. Conclusion: Mold was the main cause of IFI, with a large proportion of breakthrough IFI, presenting high mortality. The use of biomarkers and the classification of any pathological image on CT contribute to the diagnosis.

7.
Rev. chil. infectol ; 40(6)dic. 2023.
Artigo em Espanhol | LILACS-Express | LILACS | ID: biblio-1530002

RESUMO

Introducción: Las bacteriemias por Enterobacterales productores de carbapenemasa KPC (EPC-KPC) presentan una mortalidad elevada y opciones terapéuticas limitadas. Objetivos: Describir y comparar la evolución de los pacientes con bacteriemia por EPC-KPC tratados con ceftazidima/avibactam (CA) frente a otros antimicrobianos (OA). Pacientes y Métodos: Estudio prospectivo y retrospectivo de casos y controles. Se incluyeron pacientes adultos con bacteriemia por EPC-KPC, con una proporción entre casos tratados con CA y controles tratados con OA. de 1:2. Se analizaron variables clínicas, epidemiológicas y de evolución. Resultados: Se incluyeron 48 pacientes (16 CA y 32 OA). Los casos se encontraban más frecuentemente neutropénicos (50 vs.16%, p = 0,012); asimismo, presentaron medianas de score de APACHE II más altas y de score de Pitt más bajas. El 65% de la cohorte total presentó un foco clínico y Klebsiellapneumoniae fue el microorganismo más frecuentemente aislado. Los casos recibieron una mayor proporción de tratamiento antimicrobiano empírico adecuado (81 vs. 53%, p = 0,05). La antibioterapia dirigida en casos y controles fue combinada en 38 y 91%, p = 0,009. Los casos presentaron menor mortalidad al día 7 y al día 30 relacionada a infección (0 vs. 22%, p = 0,04 y 0 vs. 34%, p = 0,008). Solo los controles desarrollaron shock, ingresaron a la unidad de cuidados intensivos y presentaron bacteriemia de brecha. Conclusión: CA mostró beneficio clínico frente a OA para el tratamiento de pacientes con bacteriemia por EPC-KPC.


Background: KPC-producing Enterobacterales bacteremia (KPCCPE) is associated with a high mortality rate and limited therapeutic options. Aim: To describe and compare the outcome of patients with KPC-CPE bacteremia treated with ceftazidime/avibactam (CA) versus other antibiotics (OA). Methods: Prospective and retrospective cases and control study performed in adult patients with KPC-CPE bacteremia, with a 1:2 ratio between cases treated with CA. and controls treated with OA. Clinical, epidemiological, and outcome variables were analyzed. Results: Forty-eight patients (16 CA and 32 OA) were included. Cases were more frequently neutropenic (50 vs. 16%, p = 0.012), presented higher median APACHE II score and lower Pitt score. Of the total cohort, 65% had a clinical source, and Klebsiella pneumoniae was the most frequently isolated microorganism. Cases received more adequate empirical antibiotic treatment (81 vs. 53%, p = 0.05). Targeted antibiotic therapy in cases and controls was combined in 38 and 91%, p = 0.009. Cases had a lower 7-day mortality and 30-day infection-related mortality (0 vs. 22%, p = 0.04 and 0 vs. 34%, p = 0.008). Only controls developed shock, were admitted to the intensive care unit, and had breakthrough bacteremia. Conclusion: CA. showed clinical benefit over OA in the treatment of patients with EPC-KPC bacteremia.

8.
Materials (Basel) ; 16(22)2023 Nov 09.
Artigo em Inglês | MEDLINE | ID: mdl-38005035

RESUMO

In this study, a sol-gel film based on lead sulfide (PbS) quantum dots incorporated into a host network was synthesized as a special nanostructured composite material with potential applications in temperature sensor systems. This work dealt with the optical, structural, and morphological properties of a representative PbS quantum dot (QD)-containing thin film belonging to the Al2O3-SiO2-P2O5 system. The film was prepared using the sol-gel method combined with the spin coating technique, starting from a precursor solution containing a suspension of PbS QDs in toluene with a narrow size distribution and coated on a glass substrate in a multilayer process, followed by annealing of each deposited layer. The size (approximately 10 nm) of the lead sulfide nanocrystallites was validated by XRD and by the quantum confinement effect based on the band gap value and by TEM results. The photoluminescence peak of 1505 nm was very close to that of the precursor PbS QD solution, which demonstrated that the synthesis route of the film preserved the optical emission characteristic of the PbS QDs. The photoluminescence of the lead sulfide QD-containing film in the near infrared domain demonstrates that this material is a promising candidate for future sensing applications in temperature monitoring.

9.
Heliyon ; 9(8): e19021, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37600413

RESUMO

Immobilization of enzymes is one of the protein engineering methods used to improve their thermal and long-term stabilities. Immobilized pectinase has become an essential biocatalyst for optimization in the food processing industry. Herein, nanostructured magnetic nanoparticles were prepared in situ for use as supports to immobilize pectinase. The structural, morphological, optical and magnetic features and the chemical compositions of the nanoparticles were characterized. Nanoparticle agglomeration and low porosity were observed due to the synthetic conditions. These nanoparticles exhibited superparamagnetic behavior, which is desirable for biotechnological applications. The maximum retention rate for the enzyme was observed at pH 4.5 with a value of 1179.3 U/mgNP (units per milligram of nanoparticle), which was equivalent to a 65.6% efficiency. The free and immobilized pectinase were affected by the pH and temperature. The long-term instability caused 40% and 32% decreases in the specific activities of the free and immobilized pectinase, respectively. The effects of immobilization were analyzed with kinetic and thermodynamic studies. These results indicated a significant affinity for the substrate, a decreased reaction rate, and improved thermal stability of the immobilized pectinase. The reusability of the immobilized pectinase was preserved effectively during cycling, with only a 21.2% decrease in activity observed from the first to the last use. Therefore, alternative magnetic nanoparticles are presented for immobilizing and maintaining the thermostability of pectinase.

10.
Aging Cell ; 22(10): e13952, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37565451

RESUMO

Hutchinson-Gilford progeria syndrome (HGPS) is a rare genetic disease caused by nuclear envelope alterations that lead to accelerated aging and premature death. Several studies have linked health and longevity to cell-extrinsic mechanisms, highlighting the relevance of circulating factors in the aging process as well as in age-related diseases. We performed a global plasma proteomic analysis in two preclinical progeroid models (LmnaG609G/G609G and Zmpste24-/- mice) using aptamer-based proteomic technology. Pathways related to the extracellular matrix, growth factor response and calcium ion binding were among the most enriched in the proteomic signature of progeroid samples compared to controls. Despite the global downregulation trend found in the plasma proteome of progeroid mice, several proteins associated with cardiovascular disease, the main cause of death in HGPS, were upregulated. We also developed a chronological age predictor using plasma proteome data from a cohort of healthy mice (aged 1-30 months), that reported an age acceleration when applied to progeroid mice, indicating that these mice exhibit an "old" plasma proteomic signature. Furthermore, when compared to naturally-aged mice, a great proportion of differentially expressed circulating proteins in progeroid mice were specific to premature aging, highlighting secretome-associated differences between physiological and accelerated aging. This is the first large-scale profiling of the plasma proteome in progeroid mice, which provides an extensive list of candidate circulating plasma proteins as potential biomarkers and/or therapeutic targets for further exploration and hypothesis generation in the context of both physiological and premature aging.


Assuntos
Senilidade Prematura , Progéria , Humanos , Camundongos , Animais , Progéria/metabolismo , Senilidade Prematura/genética , Proteômica , Proteoma/metabolismo , Secretoma , Lamina Tipo A/genética , Lamina Tipo A/metabolismo
11.
Rev. chil. infectol ; 40(4)ago. 2023.
Artigo em Espanhol | LILACS-Express | LILACS | ID: biblio-1521844

RESUMO

Introducción: La infección por citomegalovirus (CMV) sigue siendo la infección con relevancia clínica más frecuente luego del trasplante alogénico de progenitores hematopoyéticos (TPHa), presentando alta morbilidad y mortalidad. Por este motivo, es importante implementar estrategias de prevención para reducir la frecuencia de la infección por CMV. Objetivo: Describir la frecuencia de infección, infección clínicamente significativa (ICS) y enfermedad por CMV en pacientes seropositivos que recibieron un TPHa y profilaxis primaria con letermovir. Pacientes y Métodos: Estudio descriptivo de cohorte longitudinal, en pacientes con TPHa seropositivos para CMV que recibieron profilaxis primaria con letermovir hasta el día 100 posTPH. Resultados: Se incluyeron 25 pacientes adultos con una mediana de edad de 41 años, el 44% fue de donante no relacionado y 36% de donante haploidéntico. Ochenta por ciento tenía tres o más factores de riesgo para infección por CMV y a 52% se le estratificó como de alto riesgo para enfermedad por CMV. La profilaxis con letermovir tuvo una mediana de duración de 97 días. Durante los 100 días pos-TPH, 20% de los pacientes presentaron infección por CMV, con carga viral plasmática detectable no cuantificable, que se negativizó en el siguiente control semanal sin discontinuación del letermovir. Ningún paciente presentó ICS ni enfermedad por CMV durante este período. Conclusión: La profilaxis con letermovir fue efectiva para prevenir la ICS y la enfermedad por CMV.


Background: Cytomegalovirus (CMV) infection remains the most common clinically significant infection after allogeneic stem cell transplantation (aSCT), with a high morbidity and mortality rate. In order to reduce its frequency, prevention strategies should be implemented. Aim: To describe the frequency of infection, clinically significant infection (CSI) and CMV disease in seropositive patients who received aSCT and primary prophylaxis with letermovir. Methods: Longitudinal descriptive cohort study in seropositive patients who received aSCT and primary prophylaxis with letermovir until day 100 post-SCT. Results: Twenty-five adult patients with a median age of 41 years were included; 44% were unrelated donors, and 36% were haploidentical donors. Eighty percent had three or more risk factors for CMV infection, and 52% were stratified as high risk for CMV disease. Letermovir prophylaxis had a median duration of 97 days. Twenty percent of the patients developed CMV infection through day 100 post-SCT, with detectable non-quantifiable CMV viral load in plasma. This became negative in the following weekly control without discontinuation of letermovir. No patient developed CSI or CMV organ disease during this period. Conclusion: Letermovir prophylaxis proved to be effective in preventing CSI and CMV disease.

12.
Int J Mol Sci ; 24(10)2023 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-37240108

RESUMO

Previously, functional coatings on 3D-printed titanium implants were developed to improve their biointegration by separately incorporating Ga and Ag on the biomaterial surface. Now, a thermochemical treatment modification is proposed to study the effect of their simultaneous incorporation. Different concentrations of AgNO3 and Ga(NO3)3 are evaluated, and the obtained surfaces are completely characterized. Ion release, cytotoxicity, and bioactivity studies complement the characterization. The provided antibacterial effect of the surfaces is analyzed, and cell response is assessed by the study of SaOS-2 cell adhesion, proliferation, and differentiation. The Ti surface doping is confirmed by the formation of Ga-containing Ca titanates and nanoparticles of metallic Ag within the titanate coating. The surfaces generated with all combinations of AgNO3 and Ga(NO3)3 concentrations show bioactivity. The bacterial assay confirms a strong bactericidal impact achieved by the effect of both Ga and Ag present on the surface, especially for Pseudomonas aeruginosa, one of the main pathogens involved in orthopedic implant failures. SaOS-2 cells adhere and proliferate on the Ga/Ag-doped Ti surfaces, and the presence of gallium favors cell differentiation. The dual effect of both metallic agents doping the titanium surface provides bioactivity while protecting the biomaterial from the most frequent pathogens in implantology.


Assuntos
Gálio , Titânio , Titânio/farmacologia , Titânio/química , Prata/farmacologia , Prata/química , Osseointegração , Porosidade , Gálio/farmacologia , Materiais Revestidos Biocompatíveis/farmacologia , Materiais Revestidos Biocompatíveis/química , Antibacterianos/farmacologia , Antibacterianos/química , Propriedades de Superfície
13.
Parasite Immunol ; 45(6): e12983, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37066749

RESUMO

Benznidazole (Bz) is the recommended drug for the treatment of Chagas disease; however, its efficacy may vary according to the sensitivity of Trypanosoma cruzi strains to the drug and host immune background. The study evaluated the immune response of peripheral blood mononuclear cells (PBMC) that were infected in vitro with the Colombian strain (Col) and treated with Bz. The co-cultures were incubated for 24 h, 5 and 10 days, where cytokine dosage was performed in the supernatant and evaluation of the cells for CD28+ and CTLA-4+ molecules in CD4+ and CD8+ lymphocytes, and CD80+ , CD86+ and HLA-DR+ in CD14+ cells. The results showed that Col induced a strong inflammatory response, with an increase in IFN-γ and TNF early in the infection (24 h), however, from 5 days of infection on, TNF production declined, and IL-10 production increased, which may be associated with a control mechanism of the exacerbated inflammatory response. The Bz treatment did not significantly alter the frequencies of the phenotypes evaluated both T cell subsets and CD14+ cells. Therefore, this study reinforces the need for typing the patient's strain to guide therapy and promote individualized treatment protocols due to the heterogeneous genetic background among T. cruzi strains.


Assuntos
Doença de Chagas , Nitroimidazóis , Tripanossomicidas , Trypanosoma cruzi , Humanos , Leucócitos Mononucleares , Colômbia , Nitroimidazóis/farmacologia , Nitroimidazóis/uso terapêutico , Doença de Chagas/tratamento farmacológico , Tripanossomicidas/farmacologia , Tripanossomicidas/uso terapêutico
14.
Pharmaceutics ; 15(3)2023 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-36986732

RESUMO

The 3D printing of titanium (Ti) offers countless possibilities for the development of personalized implants with suitable mechanical properties for different medical applications. However, the poor bioactivity of Ti is still a challenge that needs to be addressed to promote scaffold osseointegration. The aim of the present study was to functionalize Ti scaffolds with genetically modified elastin-like recombinamers (ELRs), synthetic polymeric proteins containing the elastin epitopes responsible for their mechanical properties and for promoting mesenchymal stem cell (MSC) recruitment, proliferation, and differentiation to ultimately increase scaffold osseointegration. To this end, ELRs containing specific cell-adhesive (RGD) and/or osteoinductive (SNA15) moieties were covalently attached to Ti scaffolds. Cell adhesion, proliferation, and colonization were enhanced on those scaffolds functionalized with RGD-ELR, while differentiation was promoted on those with SNA15-ELR. The combination of both RGD and SNA15 into the same ELR stimulated cell adhesion, proliferation, and differentiation, although at lower levels than those for every single moiety. These results suggest that biofunctionalization with SNA15-ELRs could modulate the cellular response to improve the osseointegration of Ti implants. Further investigation on the amount and distribution of RGD and SNA15 moieties in ELRs could improve cell adhesion, proliferation, and differentiation compared to the present study.

15.
Glia ; 71(7): 1729-1754, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-36971459

RESUMO

Chromatin access and epigenetic control over gene expression play important roles in regulating developmental processes. However, little is known about how chromatin access and epigenetic gene silencing influence mature glial cells and retinal regeneration. Herein, we investigate the expression and functions of S-adenosylhomocysteine hydrolase (SAHH; AHCY) and histone methyltransferases (HMTs) during the formation of Müller glia (MG)-derived progenitor cells (MGPCs) in the chick and mouse retinas. In chick, AHCY, AHCYL1 and AHCYL2, and many different HMTs are dynamically expressed by MG and MGPCs in damaged retinas. Inhibition of SAHH reduced levels of H3K27me3 and potently blocks the formation of proliferating MGPCs. By using a combination of single cell RNA-seq and single cell ATAC-seq, we find significant changes in gene expression and chromatin access in MG with SAHH inhibition and NMDA-treatment; many of these genes are associated with glial and neuronal differentiation. A strong correlation across gene expression, chromatin access, and transcription factor motif access in MG was observed for transcription factors known to convey glial identity and promote retinal development. By comparison, in the mouse retina, inhibition of SAHH has no influence on the differentiation of neuron-like cells from Ascl1-overexpressing MG. We conclude that in the chick the activity of SAHH and HMTs are required for the reprogramming of MG into MGPCs by regulating chromatin access to transcription factors associated with glial differentiation and retinal development.


Assuntos
Cromatina , Transdução de Sinais , Animais , Camundongos , Transdução de Sinais/fisiologia , Cromatina/metabolismo , Células-Tronco/metabolismo , Células Ependimogliais/metabolismo , Retina , Neuroglia/metabolismo , Galinhas/genética , Fatores de Transcrição/metabolismo , Proliferação de Células/fisiologia
16.
Behav Sci (Basel) ; 13(3)2023 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-36975263

RESUMO

The current scientific literature has shown significant disparity in results when physical activity is linked to academic achievement among adolescents. Thus, the main objectives of this study were (1) to analyze the relationship among students' academic achievement, intention to be physically active, and physical activity levels depending on the country (Spain or Chile), as well as to analyze these relationships based on students' socio-economic status, type of school, school year, gender, and body mass index; and (2) to analyze the differences between all these variables depending on the students' country and gender. In total, 3052 adolescents participated in the research (14.58 ± 1.39 years): 734 Chilean students (336 males and 398 females) and 2318 Spanish students (1180 males and 1138 females). Various questionnaires were used to measure the study variables. The results revealed significant relationships between academic achievement and the rest of the variables in Spanish adolescents, but in the Chilean population, academic achievement was significantly related only to socio-economic status and the type of school. Moreover, Spanish students obtained higher scores, especially the males, except for academic achievement, which was higher in females. There were also significant differences in academic achievement, intention to be physically active, physical activity levels, and socio-economic status depending on the country, with all scores being higher in Spain. Given the results, the country seems to be an important factor when comparing academic achievement and physical activity levels, besides other demographic variables.

17.
Exp Parasitol ; 247: 108478, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36731642

RESUMO

Chagas disease (CD), caused by the protozoan Trypanosoma cruzi (T. cruzi), affects millions of people worldwide. Polymerase Chain Reaction (PCR) and real-time quantitative PCR (qPCR) have been used as tools to monitor parasitic levels in the bloodstream of individuals exposed to infection, thus enabling the monitoring of relapses and the effectiveness of therapy, for example. The aim of this study was to evaluate the TcSAT-IAM system, developed by our research group, on samples from patients with suspected Chagas disease infection. Initially, primer systems were developed for the detection of the nuclear DNA (SAT-DNA) from T. cruzi (TcSAT-IAM). The Cruzi system, predicted in the literature, and TcSAT-IAM were then evaluated in relation to their analytical sensitivity, specificity and efficiency. Afterwards, the applicability of the qPCR technique using both systems (separately) for the diagnosis of acute CD was evaluated in samples from 77 individuals exposed to the outbreak that occurred in Pernambuco-Brazil, relating the results obtained to those of the classical diagnostic methods recommended for this stage of the infection. TcSAT-IAM and Cruzi had a detection limit of 1 fg of target DNA (0,003 parasites). Thirty-eight cases were recorded, 28 by laboratory criteria and 10 by clinical and epidemiological criteria. Blood samples from 77 subjects were submitted to qPCR by both systems, reaching an agreement of 89.61% between them. After analyzes between systems and diagnostic criteria, the TcSAT-IAM showed sensitivity and specificity of 52.36% (CI 37.26-67.52) and 92.31% (CI 79.68-97.35), respectively, accuracy of 72.73% and moderate agreement. The TcSAT-IAM showed an accuracy of 72.58% and 75% in relation to parasitological and serological tests (IgM anti-T. cruzi), respectively. Therefore, quantitative PCR should be incorporated into the diagnosis of suspected acute cases of Chagas disease.


Assuntos
Doença de Chagas , Trypanosoma cruzi , Humanos , Brasil/epidemiologia , Patologia Molecular , DNA de Protozoário/genética , Doença de Chagas/diagnóstico , Doença de Chagas/epidemiologia , Doença de Chagas/tratamento farmacológico , Trypanosoma cruzi/genética , Reação em Cadeia da Polimerase em Tempo Real/métodos , Surtos de Doenças
18.
Microorganisms ; 11(2)2023 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-36838476

RESUMO

Data about short courses of antibiotic therapy for Gram-negative bacilli (GNB) bacteremia in immunosuppressed patients are limited. This is a prospective observational study performed on adult patients with cancer and hematopoietic stem cell transplant (HSCT) who developed GNB bacteremia and received appropriate empirical antibiotic therapy (EAT), had a clinical response within 7 days and survived 48 h after the end of therapy. They received antibiotic therapy in the range of 7-15 days and were divided into short course, with a median of 7 days (SC), or long course, with a median of 14 days (LC). Seventy-four patients were included (SC: 36 and LC: 38). No differences were observed in baseline characteristics or in the presence of neutropenia: 58.3% vs. 60.5% (p = 0.84). Clinical presentation and microbiological characteristics were similar in SC and LC, respectively: clinical source of bacteremia 72.2% vs. 76.3% (p = 0.68); shock 2.8% vs. 10.5% (p = 0.35) and multidrug-resistant GNB 27.8% vs. 21.1% (p = 0.50). Overall, mortality was 2.8% vs. 7.9% (p = 0.61), and bacteremia relapse was 2.8% vs. 0 (p = 0.30). The length of hospitalization since bacteremia was 7 days (interquartile range (IQR), 6-15) for SC and 12 days (IQR, 7-19) (p = 0.021) for LC. In the case of patients with cancer or HSCT and GNB bacteremia who receive appropriate EAT with clinical response, 7 days of antibiotic therapy might be adequate.

19.
Antibiotics (Basel) ; 12(2)2023 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-36830136

RESUMO

Identifying the risk factors for carbapenem-resistant Enterobacterales (CRE) bacteremia in cancer and hematopoietic stem cell transplantation (HSCT) patients would allow earlier initiation of an appropriate empirical antibiotic treatment. This is a prospective multicenter observational study in patients from 12 centers in Argentina, who presented with cancer or hematopoietic stem-cell transplant and developed Enterobacterales bacteremia. A multiple logistic regression model identified risk factors for CRE bacteremia, and a score was developed according to the regression coefficient. This was validated by the bootstrap resampling technique. Four hundred and forty-three patients with Enterobacterales bacteremia were included: 59 with CRE and 384 with carbapenem-susceptible Enterobacterales (CSE). The risk factors that were identified and the points assigned to each of them were: ≥10 days of hospitalization until bacteremia: OR 4.03, 95% CI 1.88-8.66 (2 points); previous antibiotics > 7 days: OR 4.65, 95% CI 2.29-9.46 (2 points); current colonization with KPC-carbapenemase-producing Enterobacterales: 33.08, 95% CI 11.74-93.25 (5 points). With a cut-off of 7 points, a sensitivity of 35.59%, specificity of 98.43%, PPV of 77.7%, and NPV of 90.9% were obtained. The overall performance of the score was satisfactory (AUROC of 0.85, 95% CI 0.80-0.91). Finally, the post-test probability of CRE occurrence in patients with none of the risk factors was 1.9%, which would virtually rule out the presence of CRE bacteremia.

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