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1.
J Control Release ; 368: 184-198, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38395155

RESUMO

Streptococcus pneumoniae is an important human pathogen. Currently used conjugate vaccines are effective against invasive disease, but protection is restricted to serotypes included in the formulation, leading to serotype replacement. Furthermore, protection against non-invasive disease is reported to be considerably lower. The development of a serotype-independent vaccine is thus important and Pneumococcal surface protein A (PspA) is a promising vaccine candidate. PspA shows some diversity and can be classified in 6 clades and 3 families, with families 1 and 2 being the most frequent in clinical isolates. The ideal vaccine should thus induce protection against the two most common families of PspA. The aim of this work was to develop a liposome-based vaccine containing PspAs from family 1 and 2 and to characterize its immune response. Liposomes (LP) composed of dipalmitoylphosphatidylcholine (DPPC) and 3ß-[N-(N',N'-dimethylaminoethane)-carbamoyl]cholesterol (DC-Chol) with or without α-galactosylceramide (α-GalCer) were produced by microfluidics, encapsulating PspA from clade 1 (PspA1, family 1) and/or clade 4 (PspA4Pro, family 2) followed by spray-drying with trehalose to form nanocomposite microparticles carriers (NCMP). LP/NCMPs showed good stability and preservation of protein activity. LP/NCMPs containing PspA1 and/or PspA4Pro were used for immunization of mice targeting the lungs. High serum IgG antibody titers against both PspA1 and PspA4Pro were detected in animals immunized with LP/NCMPs containing α-GalCer, with a balance of IgG1 and IgG2a titers. IgG in sera from immunized mice bound to pneumococcal strains from different serotypes and expressing different PspA clades, indicating broad recognition. Mucosal IgG and IgA were also detected. Importantly, immunization with LP/NCMPs induced full protection against strains expressing PspAs from family 1 and 2. Furthermore, CD4+ resident memory T cells were detected in the lungs of the immunized animals that survived the challenge.


Assuntos
Galactosilceramidas , Infecções Pneumocócicas , Streptococcus pneumoniae , Humanos , Animais , Camundongos , Lipossomos , Pós , Infecções Pneumocócicas/prevenção & controle , Proteínas de Bactérias , Imunização , Vacinas Pneumocócicas , Imunoglobulina G , Pulmão , Anticorpos Antibacterianos , Camundongos Endogâmicos BALB C
2.
Carbohydr Polym ; 326: 121575, 2024 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-38142107

RESUMO

Naturally occurring polysaccharidic biopolymers released by marine cyanobacteria are of great interest for numerous biomedical applications, such as wound healing and drug delivery. Such polymers generally exhibit high molecular weight and an entangled structure that impact the rheology of biological fluids. However, biocompatibility tests focus not so much on rheological properties as on immune response. In the present study, the rheological behaviour of native blood plasma as a function of the concentration of a cyanobacterium biopolymer is investigated via multiple particle tracking microrheology, which measures the Brownian motion of probes embedded in a sample, and cryogenic scanning electron microscope microstructural characterisation. We use Cyanoflan as the biopolymer of choice, and profit from our knowledge of its chemical structure and its exciting potential for biotechnological applications. A sol-gel transition is identified using time-concentration superposition and the power-law behaviour of the incipient network's viscoelastic response is observed in a variety of microrheological data. Our results point to rheology-based principles for blood compatibility tests by facilitating the assignment of quantitative values to specific properties, as opposed to more heuristic approaches.


Assuntos
Plasma , Polímeros , Humanos , Reologia/métodos , Biopolímeros/química
3.
J Control Release, v. 368, p. 184-198, abr. 2024
Artigo em Inglês | Sec. Est. Saúde SP, SESSP-IBPROD, Sec. Est. Saúde SP | ID: bud-5271

RESUMO

Streptococcus pneumoniae is an important human pathogen. Currently used conjugate vaccines are effective against invasive disease, but protection is restricted to serotypes included in the formulation, leading to serotype replacement. Furthermore, protection against non-invasive disease is reported to be considerably lower. The development of a serotype-independent vaccine is thus important and Pneumococcal surface protein A (PspA) is a promising vaccine candidate. PspA shows some diversity and can be classified in 6 clades and 3 families, with families 1 and 2 being the most frequent in clinical isolates. The ideal vaccine should thus induce protection against the two most common families of PspA. The aim of this work was to develop a liposome-based vaccine containing PspAs from family 1 and 2 and to characterize its immune response. Liposomes (LP) composed of dipalmitoylphosphatidylcholine (DPPC) and 3β-[N-(N′,N′-dimethylaminoethane)-carbamoyl]cholesterol (DC-Chol) with or without α-galactosylceramide (α-GalCer) were produced by microfluidics, encapsulating PspA from clade 1 (PspA1, family 1) and/or clade 4 (PspA4Pro, family 2) followed by spray-drying with trehalose to form nanocomposite microparticles carriers (NCMP). LP/NCMPs showed good stability and preservation of protein activity. LP/NCMPs containing PspA1 and/or PspA4Pro were used for immunization of mice targeting the lungs. High serum IgG antibody titers against both PspA1 and PspA4Pro were detected in animals immunized with LP/NCMPs containing α-GalCer, with a balance of IgG1 and IgG2a titers. IgG in sera from immunized mice bound to pneumococcal strains from different serotypes and expressing different PspA clades, indicating broad recognition. Mucosal IgG and IgA were also detected. Importantly, immunization with LP/NCMPs induced full protection against strains expressing PspAs from family 1 and 2. Furthermore, CD4+ resident memory T cells were detected in the lungs of the immunized animals that survived the challenge.

4.
Sci Total Environ ; 903: 166179, 2023 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-37572895

RESUMO

Iberian lacustrine sediments are a valuable archive to document environmental changes since the last glacial termination, seen as key for anticipating future climate/environmental changes and their far-reaching implications for generations to come. Herein, multi-proxy-based indicators of a mountain lake record from Serra da Estrela were used to reconstruct atmospheric (in)fluxes and associated climatic/environmental changes over the last ∼13.5 ka. Depositions of long-range transported dust (likely from the Sahara) and halogens (primarily derived from seawater) were higher for the pre-Holocene, particularly in the late Bølling-Allerød-Younger Dryas period, compared to the Holocene. This synchronous increase could be related to a recognized dust-laden atmosphere, along with the combined effect of (i) an earlier proposed effective transport of Sahara dust for higher latitudes during cold periods and (ii) the progressive Polar Front expansion southwards, with the amplification of halogen activation reactions in lower latitudes due to greater closeness to snow/sea ice (halide-laden) surfaces. Additionally, the orographic blocking of Serra da Estrela may have played a critical role in increasing precipitation of Atlantic origin at higher altitudes, with the presence of snow prompting physical and chemical processes involving halogen species. In the Late Holocene, the dust proxy records highlighted two periods of enhanced input to Lake Peixão, the first (∼3.5-2.7 ka BP) after the end of the last African Humid Period and the second, from the 19th century onwards, agreeing with the advent of commercial agriculture, and human contribution to land degradation and dust emission in the Sahara/Sahel region. The oceanic imprints throughout the Holocene matched well with North Atlantic rapid climatic changes that, in turn, coincided with ice-rafted debris or Bond events and other records of increased storminess for the European coasts. Positive parallel peaks in halogens were found in recent times, probably connected to fire extinction by halogenated alkanes and roadway de-icing.

5.
Inflamm Res ; 72(5): 895-899, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36917217

RESUMO

OBJECTIVE: To evaluate whether colchicine treatment was associated with the inhibition of NLRP3 inflammasome activation in patients with COVID-19. METHODS: We present a post hoc analysis from a double-blinded placebo-controlled randomized clinical trial (RCT) on the effect of colchicine for the treatment of COVID-19. Serum levels of NOD-like receptor protein 3 (NLRP3) inflammasome products-active caspase-1 (Casp1p20), IL-1ß, and IL-18-were assessed at enrollment and after 48-72 h of treatment in patients receiving standard-of-care (SOC) plus placebo vs. those receiving SOC plus colchicine. The colchicine regimen was 0.5 mg tid for 5 days, followed by 0.5 mg bid for another 5 days. RESULTS: Thirty-six patients received SOC plus colchicine, and thirty-six received SOC plus placebo. Colchicine reduced the need for supplemental oxygen and the length of hospitalization. On Days 2-3, colchicine lowered the serum levels of Casp1p20 and IL-18, but not IL-1ß. CONCLUSION: Treatment with colchicine inhibited the activation of the NLRP3 inflammasome, an event triggering the 'cytokine storm' in COVID-19. TRIAL REGISTRATION NUMBERS: RBR-8jyhxh.


Assuntos
COVID-19 , Inflamassomos , Humanos , Inflamassomos/metabolismo , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Interleucina-18 , Proteínas NLR , Colchicina/uso terapêutico , Interleucina-1beta/metabolismo
6.
Pulmonology ; 2023 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-36797150

RESUMO

INTRODUCTION AND OBJECTIVES: Portugal is one of the countries with the highest number of visits to the emergency department (ED), 31% classified as "non-urgent" or "avoidable." The objectives of our study were to evaluate the size and characteristics of patients with pulmonary disease who overuse the ED, and identify factors associated with mortality. MATERIALS AND METHODS: A retrospective cohort study was conducted, based on the medical records of ED frequent users (ED-FU) with pulmonary disease who attended a university hospital center in the northern inner city of Lisbon from January 1 to December 31, 2019. To evaluate mortality, a follow-up until December 31, 2020 was performed. RESULTS: Over 5,567 (4.3%) patients were identified as ED-FU and 174 (0.14%) had pulmonary disease as the main clinical condition, accounting for 1,030 ED visits. 77.2% of ED visits were categorized as "urgent/very urgent." A high mean age (67.8 years), male gender, social and economic vulnerability, high burden of chronic disease and comorbidities, with a high degree of dependency, characterized the profile of these patients. A high proportion (33.9%) of patients did not have a family physician assigned and this was the most important factor associated with mortality (p<0.001; OR: 24.394; CI 95%: 6.777-87.805). Advanced cancer disease and autonomy deficit were other clinical factors that most determined the prognosis. CONCLUSIONS: Pulmonary ED-FU are a small group of ED-FU who constitute an aged and heterogeneous group with a high burden of chronic disease and disability. The lack of an assigned family physician was the most important factor associated with mortality, as well as advanced cancer disease and autonomy deficit.

7.
Eur Ann Allergy Clin Immunol ; 55(4): 180-188, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-35261226

RESUMO

Summary: Background. Patients and Public Involvement in every stage of the patient-centered health research cycle is the key to the development of innovative solutions with an impact on patients' care. Methods. This protocol describes the development of ConectAR, a network to promote the involvement of patients with asthma and their carers in the health research cycle. Results. This protocol comprehends 4 tasks: 1) define the mission, vision, governance and activities of the network through focus groups; 2) establish the communication strategy and tools; 3) test the feasibility of the network in a Delphi study on the research priorities for asthma in Portugal; 4) coordination and dissemination activities. Conclusions. This network will improve research by ensuring that patients and carers have an active role in the co-creation of impactful solutions for asthma.


Assuntos
Asma , Cuidadores , Humanos , Grupos Focais , Portugal
8.
Plant Biol (Stuttg) ; 25(1): 161-175, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36278887

RESUMO

In Metrodorea nigra, a Rutaceae species with rhythmic growth, the shoot apex in the dormant stage is enclosed by modified stipules. The young organs are fully covered with peltate secretory trichomes, and these structures remain immersed in a hyaline exudate within a hood-shaped structure. Our study focused on the morpho-functional characterization of the peltate trichomes and cytological events associated with secretion. Shoot apices were collected during both dormant and active stages and processed for anatomical, cytochemical and ultrastructural studies. Trichomes initiate secretion early on, remain active throughout leaf development, but collapse as the leaves expand; at which time secretory cavities start differentiation in the mesophyll and secretion increases as the leaf reaches full expansion. The subcellular apparatus of the trichome head cells is consistent with hydrophilic and lipophilic secretion. Secretion involves two vesicle types: the smaller vesicles are PATAg-positive (periodic acid/thiocarbohydrazide/silver proteinate) for carbohydrates and the larger ones are PATAg-negative. In the first phase of secretory activity, the vesicles containing polysaccharides discharge their contents through exocytosis with the secretion accumulating beneath the cuticle, which detaches from the cell wall. Later, a massive discharge of lipophilic substances (lipids and terpenes/phenols) results in their accumulation between the wall and cuticle. Release of the secretions occurs throughout the cuticular microchannels. Continued protection of the leaves throughout shoot development is ensured by replacement of the collapsed secretory trichomes by oil-secreting cavities. Our findings provide new perspectives for understanding secretion regulation in shoot apices of woody species with rhythmic growth.


Assuntos
Rutaceae , Tricomas , Tricomas/ultraestrutura , Terpenos/química , Folhas de Planta/química , Fenóis/análise
9.
Soft Matter ; 18(39): 7510-7523, 2022 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-36148801

RESUMO

There has been enormous interest in the production of fluids with rheological properties similar to those of real blood over the last few years. Application fields range from biomicrofluidics (microscale) to forensic science (macroscale). The inclusion of flexible microparticles in blood analogue fluids has been demonstrated to be essential in order to reproduce the behaviour of blood flow in these fields. Here, we describe a protocol to produce a whole human blood analogue composed of a proposed plasma analogue and flexible spherical microparticles that mimic the key structural attributes of RBCs (size and mechanical properties), at a concentration matching the human haematocrit (∼42% by volume). Polydimethylsiloxane (PDMS) flexible microparticles were used to mimic RBCs, whose capability to deform is tunable by means of the mixing ratio of the PDMS precursor. Their flow through glass micronozzles allowed us to find the appropriate mixing ratio of PDMS to have approximately the same Young's modulus (E) as that exhibited by real RBCs. Shear and extensional rheology and microrheology techniques were used to match the properties exhibited by human plasma and whole blood at body temperature (37 °C). Finally, we study the flow of our proposed fluid through a microfluidic channel, showing the in vitro reproduction of the multiphase flow effects taking place in the human microcirculatory system, such as the cell-free layer (CFL) and the Fåhræus-Lindqvist effect. A macroscale application in the field of forensic science is also presented, concerning the impact of our blood analogue droplets on a solid surface for bloodstain pattern analysis.


Assuntos
Substitutos Sanguíneos , Dimetilpolisiloxanos , Hematócrito , Humanos , Microcirculação , Plasma
10.
Physiotherapy ; (114): 77-84, Mar. 2022. graf, tab
Artigo em Inglês | CONASS, Sec. Est. Saúde SP, SESSP-IDPCPROD, Sec. Est. Saúde SP | ID: biblio-1343908

RESUMO

OBJECTIVES: To determine whether the time for peak exercise heart rate to return to resting heart rate after the 6-minute walk test (6MWT) can predict cardiac events in patients with heart failure (HF) within 2 years. DESIGN: Prospective cohort study. SETTING: HF outpatient facility at a tertiary teaching hospital. PARTICIPANTS: Seventy-six patients with HF, New York Heart Association functional classification II and III, and left ventricular ejection fraction <50% MAIN OUTCOME MEASURES: Patients used a heart rate monitor to measure the time for peak exercise heart rate to return to resting heart rate after the 6MWT. Data were analysed using Polar Pro-Trainer 5 software (Kempele, Finland). Patients were followed for >2 years for cardiac events (hospitalisations and death). RESULTS: Thirty-four patients had cardiac events during the 2-year follow-up period. There was a significant difference in time to return to resting heart rate between the groups with and without cardiac events {with 3.6 [standard deviation (SD) A] vs without 2.8 (SD B) minutes; mean difference C; 95% confidence interval (CI) of the difference D to E; P=0.003}. No significant differences between patients with and without cardiac events were found for mean walking distance, mean heart rate recovery at 1 minute and mean heart rate recovery at 2 minutes. The receiver operating curve discriminated between patients with and without cardiac events (área under the curve 0.71, 95% CI 0.61 to 0.81; P< 0.001). Using logistic regression analysis, prolonged time to return to resting heart rate (≥3 minutes) independently increased the risk for cardiac events 6.9-fold (95% CI 2.34 to 20.12; P< 0.001). The Kaplan­Meier curve showed more cardiac events in patients with prolonged time to return to resting heart rate (P=0.028). CONCLUSIONS: Prolonged time to return to resting heart rate (≥3 minutes) after the 6MWT was an independent predictor of cardiac events in patients with HF.


Assuntos
Capacidade Residual Funcional , Teste de Caminhada , Insuficiência Cardíaca , Frequência Cardíaca
11.
J Mol Med (Berl) ; 100(2): 215-243, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34800164

RESUMO

The aryl hydrocarbon receptor (AHR) is a ligand-activated transcription factor that can be activated by structurally diverse compounds arising from the environment and the microbiota and host metabolism. Expanding evidence has been shown that the modulation of the canonical pathway of AHR occurs during several chronic diseases and that its abrogation might be of clinical interest for metabolic and inflammatory pathological processes. However, most of the evidence on the pharmacological abrogation of the AHR-CYP1A1 axis has been reported in vitro, and therefore, guidance for in vivo studies is needed. In this review, we cover the state-of-the-art of the pharmacodynamic and pharmacokinetic properties of AHR antagonists and CYP1A1 inhibitors in different in vivo rodent (mouse or rat) models of disease. This review will serve as a road map for those researchers embracing this emerging therapeutic area targeting the AHR. Moreover, it is a timely opportunity as the first AHR antagonists have recently entered the clinical stage of drug development.


Assuntos
Citocromo P-450 CYP1A1/antagonistas & inibidores , Inibidores das Enzimas do Citocromo P-450/farmacologia , Receptores de Hidrocarboneto Arílico/antagonistas & inibidores , Animais , Humanos , Receptores de Hidrocarboneto Arílico/metabolismo
12.
Sci Total Environ ; 812: 152474, 2022 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-34952068

RESUMO

Long-chain unsaturated alkenones produced by haptophyte algae are widely used as paleotemperature indicators. The unsaturation relationship to temperature is linear at mid-latitudes, however, non-linear responses detected in subpolar regions of both hemispheres have suggested complicating factors in these environments. To assess the influence of biotic and abiotic factors in alkenone production and preservation in the Subantarctic Zone, alkenone fluxes were quantified in three vertically-moored sediment traps deployed at the SOTS observatory (140°E, 47°S) during a year. Alkenone fluxes were compared with coccolithophore assemblages, satellite measurements and surface-water properties obtained by sensors at SOTS. Alkenone-based temperature reconstructions generally mirrored the seasonal variations of SSTs, except for late winter when significant deviations were observed (3-10 °C). Annual flux-weighted averages in the 3800 m trap returned alkenone-derived temperatures ~1.5 °C warmer than those derived from the 1000 m trap, a distortion attributed to surface production and signal preservation during its transit through the water column. Notably, changes in the relative abundance of E. huxleyi var. huxleyi were positively correlated with temperature deviations between the alkenone-derived temperatures and in situ SSTs (r = 0.6 and 0.7 at 1000 and 2000 m, respectively), while E. huxleyi var. aurorae, displayed an opposite trend. Our results suggest that E. huxleyi var. aurorae produces a higher proportion of C37:3 relative to C37:2 compared to its counterparts. Therefore, the dominance of var. aurorae south of the Subtropical Front could be at least partially responsible for the less accurate alkenone-based SST reconstructions in the Southern Ocean using global calibrations. However, the observed correlations were largely influenced by the samples collected during winter, a period characterized by low particle fluxes and slow sinking rates. Thus, it is likely that other factors such as selective degradation of the most unsaturated alkenones could also account for the deviations of the alkenone paleothermometer.


Assuntos
Haptófitas , Ecótipo , Oceanos e Mares , Temperatura
13.
Physiotherapy ; 114: 77-84, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34563383

RESUMO

OBJECTIVES: To determine whether the time for peak exercise heart rate to return to resting heart rate after the 6-minute walk test (6MWT) can predict cardiac events in patients with heart failure (HF) within 2 years. DESIGN: Prospective cohort study. SETTING: HF outpatient facility at a tertiary teaching hospital. PARTICIPANTS: Seventy-six patients with HF, New York Heart Association functional classification II and III, and left ventricular ejection fraction <50%. MAIN OUTCOME MEASURES: Patients used a heart rate monitor to measure the time for peak exercise heart rate to return to resting heart rate after the 6MWT. Data were analysed using Polar Pro-Trainer 5 software (Kempele, Finland). Patients were followed for >2 years for cardiac events (hospitalisations and death). RESULTS: Thirty-four patients had cardiac events during the 2-year follow-up period. However, there was a significant difference in the time to return to resting heart rate between the groups with and without cardiac events {with 3.6 (SD 1.1) vs without 2.8 (SD 1.1) minutes; mean difference of 0.79 (95% confidence interval (CI) of the difference 0.28 to 1.28; P=0.003}. No significant differences between patients with and without cardiac events were found for mean walking distance, mean heart rate recovery at 1minute and mean heart rate recovery at 2minutes. The receiver operating curve discriminated between patients with and without cardiac events (área under the curve 0.71, 95% CI 0.61 to 0.81; P<0.001). Using logistic regression analysis, prolonged time to return to resting heart rate (≥3minutes) independently increased the risk for cardiac events 6.9-fold (95% CI 2.34 to 20.12; P<0.001). The Kaplan-Meier curve showed more cardiac events in patients with prolonged time to return to resting heart rate (P=0.028). CONCLUSIONS: Prolonged time to return to resting heart rate (≥3minutes) after the 6MWT was an independent predictor of cardiac events in patients with HF.


Assuntos
Insuficiência Cardíaca , Função Ventricular Esquerda , Teste de Esforço , Tolerância ao Exercício/fisiologia , Frequência Cardíaca , Humanos , Estudos Prospectivos , Fatores de Risco , Volume Sistólico/fisiologia , Teste de Caminhada
14.
Braz J Med Biol Res ; 54(10): e11439, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34378678

RESUMO

Cathepsin Z (CTSZ) is a cysteine protease responsible for the adhesion and migration of both immune and tumor cells. Due to its dual role, we hypothesized that the site of CTSZ expression could be determinant of the pro- or anti-tumorigenic effects of this enzyme. To test this hypothesis, we analyzed CTSZ expression data in healthy and tumor tissues by bioinformatics and evaluated the expression levels of CTSZ mRNA in the blood cells of prostate cancer (PCa) patients by qRT-PCR compared with healthy subjects, evaluating its diagnostic and prognostic implications for this type of cancer. Immune cells present in the blood of healthy patients overexpress CTSZ. In PCa, we found decreased CTSZ mRNA levels in blood cells, 75% lower than in healthy subjects, that diminished even more during biochemical relapse. CTSZ mRNA in the blood cells had an area under the curve for PCa diagnosis of 0.832, with a 93.3% specificity, and a positive likelihood ratio of 9.4. The site of CTSZ mRNA expression is fundamental to determine its final role as a protective determinant in PCa, such as CTSZ mRNA in the blood cells, or a malignant determinant, such as found for CTSZ expressed in high levels by different types of primary and metastatic tumors. Low CTSZ mRNA expression in the total blood is a possible PCa marker complementary to prostate-specific antigen (PSA) for biopsy decisions, with the potential to eliminate unnecessary biopsies.


Assuntos
Catepsina Z , Neoplasias da Próstata , Células Sanguíneas , Humanos , Masculino , Prognóstico , Antígeno Prostático Específico , Neoplasias da Próstata/diagnóstico , RNA Mensageiro
16.
Mol Metab ; 51: 101241, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-33933677

RESUMO

BACKGROUND AND OBJECTIVES: The therapeutic effects of the dopamine D2 receptor (D2R) agonist, bromocriptine, in type 2 diabetes (T2D) have been attributed to central nervous system actions. However, peripheral dopamine directly modulates glucose uptake in insulin-sensitive tissues and lipid metabolism in adipose tissue (AT). We hypothesized that the dopaminergic system may be impaired in the adipose tissue of patients with T2D and that the therapeutic actions of bromocriptine could involve the modulation of metabolism in this tissue. METHODS: The expression of dopamine receptors was evaluated in visceral AT samples from patients with obesity and stratified in several groups: insulin sensitive (IS); insulin resistance (IR) normoglycaemic; insulin resistant prediabetic; insulin resistant diabetic, according to Ox-HOMA2IR, fasting glycaemia and HbA1c levels. T2D Goto-Kakizaki rats (GK) were fed a high-caloric diet (HCD) for five months and treated with bromocriptine (10 mg/kg/day, i.p.) in the last month. The levels of dopaminergic system mediators and markers of insulin sensitivity and glucose and lipid metabolism were assessed in the peri-epididymal adipose tissue (pEWAT) and brown (BAT) adipose tissues, liver, and skeletal muscle. RESULTS: Patients with IR presented a decreasing trend of DRD1 expression in the visceral adipose tissue, being correlated with the expression of UCP1, PPARA, and insulin receptor (INSR) independently of insulin resistance and body mass index. Although no differences were observed in DRD2, DRD4 expression was significantly decreased in patients with prediabetes and T2D. In HCD-fed diabetic rats, bromocriptine increased D1R and tyrosine hydroxylase (TH) levels in pEWAT and the liver. Besides reducing adiposity, bromocriptine restored GLUT4 and PPARγ levels in pEWAT, as well as postprandial InsR activation and postabsorptive activation of lipid oxidation pathways. A reduction of liver fat, GLUT2 levels and postprandial InsR and AMPK activation in the liver was observed. Increased insulin sensitivity and GLUT4 levels in BAT and an improvement of the overall metabolic status were observed. CONCLUSIONS: Bromocriptine treatment remodels adipose tissue and the liver dopaminergic system, with increased D1R and TH levels, resulting in higher insulin sensitivity and catabolic function. Such effects may be involved in bromocriptine therapeutic effects, given the impaired expression of dopamine receptors in the visceral adipose tissue of IR patients, as well as the correlation of D1R expression with InsR and metabolic mediators.


Assuntos
Bromocriptina/farmacologia , Diabetes Mellitus Tipo 2/tratamento farmacológico , Agonistas de Dopamina/farmacologia , Gordura Intra-Abdominal/efeitos dos fármacos , Obesidade/terapia , Adulto , Idoso , Animais , Cirurgia Bariátrica , Bromocriptina/uso terapêutico , Estudos de Coortes , Diabetes Mellitus Tipo 2/metabolismo , Modelos Animais de Doenças , Dopamina/metabolismo , Agonistas de Dopamina/uso terapêutico , Feminino , Humanos , Resistência à Insulina , Gordura Intra-Abdominal/metabolismo , Gordura Intra-Abdominal/cirurgia , Metabolismo dos Lipídeos/efeitos dos fármacos , Masculino , Redes e Vias Metabólicas/efeitos dos fármacos , Metaboloma/efeitos dos fármacos , Metabolômica , Pessoa de Meia-Idade , Obesidade/complicações , Obesidade/metabolismo , Ratos , Receptores de Dopamina D2/agonistas , Receptores de Dopamina D2/metabolismo
17.
Braz. j. med. biol. res ; 54(10): e11439, 2021. tab, graf
Artigo em Inglês | LILACS | ID: biblio-1285649

RESUMO

Cathepsin Z (CTSZ) is a cysteine protease responsible for the adhesion and migration of both immune and tumor cells. Due to its dual role, we hypothesized that the site of CTSZ expression could be determinant of the pro- or anti-tumorigenic effects of this enzyme. To test this hypothesis, we analyzed CTSZ expression data in healthy and tumor tissues by bioinformatics and evaluated the expression levels of CTSZ mRNA in the blood cells of prostate cancer (PCa) patients by qRT-PCR compared with healthy subjects, evaluating its diagnostic and prognostic implications for this type of cancer. Immune cells present in the blood of healthy patients overexpress CTSZ. In PCa, we found decreased CTSZ mRNA levels in blood cells, 75% lower than in healthy subjects, that diminished even more during biochemical relapse. CTSZ mRNA in the blood cells had an area under the curve for PCa diagnosis of 0.832, with a 93.3% specificity, and a positive likelihood ratio of 9.4. The site of CTSZ mRNA expression is fundamental to determine its final role as a protective determinant in PCa, such as CTSZ mRNA in the blood cells, or a malignant determinant, such as found for CTSZ expressed in high levels by different types of primary and metastatic tumors. Low CTSZ mRNA expression in the total blood is a possible PCa marker complementary to prostate-specific antigen (PSA) for biopsy decisions, with the potential to eliminate unnecessary biopsies.


Assuntos
Humanos , Masculino , Neoplasias da Próstata/diagnóstico , Catepsina Z , Prognóstico , Células Sanguíneas , RNA Mensageiro , Antígeno Prostático Específico
18.
Parasit Vectors ; 13(1): 527, 2020 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-33081837

RESUMO

BACKGROUND: Infection by nematodes is a problem for human health, livestock, and agriculture, as it causes deficits in host health, increases production costs, and incurs a reduced food supply. The control of these parasites is usually done using anthelmintics, which, in most cases, have not been fully effective. Therefore, the search for new molecules with anthelmintic potential is necessary. METHODS: In the present study, we isolated and characterized molecules from the nematophagous fungus Pochonia chlamydosporia and tested these compounds on three nematodes: Caenorhabditis elegans; Ancylostoma ceylanicum; and Ascaris suum. RESULTS: The ethyl acetate extract showed nematicidal activity on the nematode model C. elegans. We identified the major substance present in two sub-fractions of this extract as ketamine. Then, we tested this compound on C. elegans and the parasites A. ceylanicum and A. suum using hamsters and mice as hosts, respectively. We did not find a difference between the animal groups when considering the number of worms recovered from the intestines of animals treated with ketamine (6 mg) and albendazole (P > 0.05). The parasite burden of larvae recovered from the lungs of mice treated with ketamine was similar to those treated with ivermectin. CONCLUSIONS: The results presented here demonstrate the nematicidal activity of ketamine in vitro and in vivo, thus confirming the nematicidal potential of the molecule present in the fungus P. chlamydosporia may consist of a new method of controlling parasites.


Assuntos
Hypocreales/metabolismo , Ketamina , Nematoides , Albendazol/farmacologia , Ancylostoma/efeitos dos fármacos , Animais , Antinematódeos/metabolismo , Antinematódeos/farmacologia , Ascaris suum/efeitos dos fármacos , Caenorhabditis elegans/efeitos dos fármacos , Cricetinae , Ivermectina/farmacologia , Ketamina/metabolismo , Ketamina/farmacologia , Camundongos , Nematoides/efeitos dos fármacos , Nematoides/microbiologia , Controle Biológico de Vetores/métodos
20.
Eur J Radiol ; 120: 108646, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31526892

RESUMO

PURPOSE: Appropriate lung nodule management is essential to minimizing unnecessary patient recall in lung cancer screening. Two European guidelines provide differing recommendations in that participants with nodules ≥100 mm3 or ≥80 mm3 respectively should be recalled, at baseline. Nodule size estimation is known to vary between volumetry software packages (VSPs). The aim of this study was to examine the impact of choice of VSP on participant recall rates, when applying different European nodule management guidelines. An additional aim was to compare recall rates between 7 VSPs and manual diameter measurements. METHODS: 156 small-sized lung nodules (50-150 mm3) from the UK Lung Screening trial were measured using 7 different VSPs (VSP1-7) and also using manual diameter. The type of VSP used in the NELSON study (VSP1), on which European nodule management guidelines are based, provided the reference standard. Nodule size was compared using Bland Altman, and recall rates by Mcnemar's test. RESULTS: Compared to the reference standard, a 100 mm3 threshold for recall, resulted in no difference in recall rates only for VSP 5 & 7. Using an 80mm3 threshold resulted in no difference in recall rates for VSP2 & 6. Recall rates were significantly higher for VSP 4 regardless of threshold and when using manual diameter measurements. CONCLUSIONS: Appropriate nodule size thresholds for recall in screening depend on the type of volumetry software used. The results highlight the importance of benchmarking of volumetry packages.


Assuntos
Detecção Precoce de Câncer/métodos , Neoplasias Pulmonares/patologia , Tomada de Decisão Clínica , Humanos , Pulmão/diagnóstico por imagem , Neoplasias Pulmonares/diagnóstico por imagem , Neoplasias Pulmonares/prevenção & controle , Software , Nódulo Pulmonar Solitário/diagnóstico por imagem , Nódulo Pulmonar Solitário/patologia , Tomografia Computadorizada por Raios X/métodos , Carga Tumoral
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