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1.
Physiol Plant ; 176(2): e14273, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38566156

RESUMO

Sacoglossa sea slugs have garnered attention due to their ability to retain intracellular functional chloroplasts from algae, while degrading other algal cell components. While protective mechanisms that limit oxidative damage under excessive light are well documented in plants and algae, the photoprotective strategies employed by these photosynthetic sea slugs remain unresolved. Species within the genus Elysia are known to retain chloroplasts from various algal sources, but the extent to which the metabolic processes from the donor algae can be sustained by the sea slugs is unclear. By comparing responses to high-light conditions through kinetic analyses, molecular techniques, and biochemical assays, this study shows significant differences between two photosynthetic Elysia species with chloroplasts derived from the green alga Acetabularia acetabulum. Notably, Elysia timida displayed remarkable tolerance to high-light stress and sophisticated photoprotective mechanisms such as an active xanthophyll cycle, efficient D1 protein recycling, accumulation of heat-shock proteins and α-tocopherol. In contrast, Elysia crispata exhibited absence or limitations in these photoprotective strategies. Our findings emphasize the intricate relationship between the host animal and the stolen chloroplasts, highlighting different capacities to protect the photosynthetic organelle from oxidative damage.


Assuntos
Acetabularia , Gastrópodes , Animais , Plastídeos/metabolismo , Cloroplastos/metabolismo , Fotossíntese , Gastrópodes/metabolismo
2.
PLoS One ; 19(4): e0298187, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38648225

RESUMO

Burnout is most commonly defined as a syndrome characterized by emotional exhaustion, cynicism, and ineffectiveness, which occurs in response to chronic stressors at work. It can adversely affect health workers' physical and mental health, and the quality of care provided. The COVID-19 pandemic increased stressors and could impact burnout prevalence in this group. There is a lack of information regarding the prevalence of burnout among hospital health workers in Brazil. A newer definition of burnout has been proposed that considers three different clinical profiles: the frenetic, underchallenged and worn-out subtypes. This differentiation could lead to interventions tailored for each subtype. The present study aimed to estimate the prevalence of burnout, its subtypes, and associated factors in workers of a public hospital network in Brazil, during the pandemic. A total of 143 randomly selected participants answered an online form that included sociodemographic and occupational items, and the Burnout Clinical Subtypes Questionnaire, a summarized version. This questionnaire evaluates three burnout dimensions (overload, lack of development, neglect) that can be used to discriminate the three burnout subtypes (frenetic, underchallenged, worn-out, respectively); higher scores indicate higher burnout levels. The prevalence of burnout was high (53.85%), similar to other studies during the pandemic. The most common subtypes were 'frenetic' (34.97%), characterized by increased efforts to meet work demands, to the point of neglecting personal needs, and 'lack of development' (23.78%), characterized by a sense that work is uninteresting and does not contribute to personal development, and a perfunctory behavior towards tasks. Age was associated with burnout: workers with less than 51 years presented higher levels of burnout. These findings indicate the need for effective interventions to prevent and/or treat burnout. The assessment of burnout subtypes can allow managers to better understand the processes affecting employees, and inform actions to improve workforce health.

3.
Heliyon ; 10(4): e25872, 2024 Feb 29.
Artigo em Inglês | MEDLINE | ID: mdl-38434016

RESUMO

The fraudulent mislabelling of seafood geographic origin has been growing due to complex supply chains and growing consumer demand. To address this issue, seafood traceability tools, such as those based on elemental fingerprints (EF) of bivalve shells, have been successfully used to confirm their harvesting location. However, despite the usefulness of these methodologies, there is still room for optimization. Therefore, this study evaluated the effects of a routine procedure during bivalve shells preparation for ICP-MS analysis - their pretreatment with H2O2 to remove organic components. More specifically, the present study evaluated the effects of H2O2 on i) the elemental fingerprints of shells of two bivalve species (Ruditapes philippinarum and Cerastoderma edule) from four different locations over the north-western and the western Iberian coast, and ii) their influence on the accuracy of models (based on the EF of shells) used to confirm the geographic origin of these species. Significant differences were observed between untreated and pretreated shells of R. philippinarum (p within location ranging from 0.0001 to 0.0011) and C. edule (p ranging from 0.0001 to 0.0007 for C. edule) for both their elemental fingerprints as a whole and several individual elements. The accuracy of the models employed to determine the origin of the two bivalve species, using i) untreated shells, ii) pretreated shells, and iii) both pretreated and untreated shells grouped per location, was high, with the models accurately predicting the geographic origin of 100, 90 and 95% of R. philippinarum and 95, 100 and 95% of C. edule, respectively. These results show that the shifts in the EF of bivalve shells promoted by treating them with H2O2 prior to ICP-MS analysis did not affect the accuracy of the models used to confirm the geographic origin of both bivalve species. Therefore, the need to pre-treat bivalve shells with H2O2 can be dismissed in future studies addressing the traceability of bivalves when using ICP-MS, thus contributing to reducing environmental impacts and economic costs associated with this procedure, as well as the time required to obtain results.

5.
Sci Rep ; 13(1): 22634, 2023 12 19.
Artigo em Inglês | MEDLINE | ID: mdl-38114557

RESUMO

Cervical cancer (CC) poses a significant burden on individuals in developing regions, exhibiting heterogeneous responses to standard chemoradiation therapy, and contributing to substantial mortality rates. Unraveling host immune dynamics holds promise for innovative therapies and discovery of clinically relevant biomarkers. We studied prospectively locally advanced CC patients pre-treatment, stratifying them as responders (R) or non-responders (NR). R patients had increased tumor-infiltrating lymphocytes (TILs), while NR patients showed elevated PD-1 scores, CD8+ and PD-L2+ TILs, and PD-L1 immune reactivity. NR patients exhibited higher systemic soluble mediators correlating with TIL immune markers. R patients demonstrated functional polarization of CD4 T cells (Th1, Th2, Th17, and Treg), while CD8+ T cells and CD68+ macrophages predominated in the NR group. Receiver operating characteristic analysis identified potential CC response predictors, including PD-L1-immunoreactive (IR) area, PD-L2, CD8, FGF-basic, IL-7, IL-8, IL-12p40, IL-15, and TNF-alpha. Dysfunctional TILs and imbalanced immune mediators contribute to therapeutic insufficiency, shedding light on local and systemic immune interplay. Our study informs immunological signatures for treatment prediction and CC prognosis.


Assuntos
Neoplasias do Colo do Útero , Feminino , Humanos , Neoplasias do Colo do Útero/terapia , Antígeno B7-H1 , Prognóstico , Linfócitos T CD8-Positivos , Fatores Imunológicos , Linfócitos do Interstício Tumoral , Biomarcadores Tumorais
6.
ARP Rheumatol ; 2(3): 188-199, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37728117

RESUMO

AIMS: To characterise the idiopathic inflammatory myopathies (IIM) module of the Rheumatic Diseases Portuguese Register (Reuma.pt/myositis) and the patients in its cohort. METHODS: Reuma.pt is a web-based system with standardised patient files gathered in a registry. This was a multicentre open cohort study, including patients registered in Reuma.pt/myositis up to January 2022. RESULTS: Reuma.pt/myositis was designed to record all relevant data in clinical practice and includes disease-specific diagnosis and classification criteria, clinical manifestations, immunological data, and disease activity scores. Two hundred eighty patients were included, 71.4% female, 89.4% Caucasian, with a median age at diagnosis and disease duration of 48.9 (33.6-59.3) and 5.3 (3.0-9.8) years. Patients were classified as having definite (N=57/118, 48.3%), likely (N=23/118, 19.5%), or possible (N=2/118, 1.7%) IIM by 2017 EULAR/ACR criteria. The most common disease subtypes were dermatomyositis (DM, N=122/280, 43.6%), polymyositis (N=59/280, 21.1%), and myositis in overlap syndromes (N=41/280, 14.6%). The most common symptoms were proximal muscle weakness (N=180/215, 83.7%) and arthralgia (N=127/249, 52.9%), and the most common clinical signs were Gottron's sign (N=75/184, 40.8%) and heliotrope rash (N=101/252, 40.1%). Organ involvement included lung (N=78/230, 33.9%) and heart (N=11/229, 4.8%) involvements. Most patients expressed myositis-specific (MSA, N=158/242, 65.3%) or myositis-associated (MAA, 112/242, 46.3%) antibodies. The most frequent were anti-SSA/SSB (N=70/231, 30.3%), anti-Jo1 (N=56/236, 23.7%), and anti-Mi2 (N=31/212, 14.6%). Most patients had a myopathic pattern on electromyogram (N=101/138, 73.2%), muscle oedema in magnetic resonance (N=33/62, 53.2%), and high CK (N=154/200, 55.0%) and aldolase levels (N=74/135, 54.8%). Cancer was found in 11/127 patients (8.7%), most commonly breast cancer (N=3/11, 27.3%). Most patients with cancer-associated myositis had DM (N=8/11, 72.7%) and expressed MSA (N=6/11) and/or MAA (N=3/11). The most used drugs were glucocorticoids (N=201/280, 71.8%), methotrexate (N=117/280, 41.8%), hydroxychloroquine (N=87/280, 31.1%), azathioprine (N=85/280, 30.4%), and mycophenolate mofetil (N=56/280, 20.0%). At the last follow-up, there was a median MMT8 of 150 (142-150), modified DAS skin of 0 (0-1), global VAS of 10 (0-50) mm, and HAQ of 0.125 (0.000-1.125). CONCLUSIONS: Reuma.pt/myositis adequately captures the main features of inflammatory myopathies' patients, depicting, in this first report, a heterogeneous population with frequent muscle, joint, skin, and lung involvements.

8.
BMC Plant Biol ; 23(1): 294, 2023 Jun 02.
Artigo em Inglês | MEDLINE | ID: mdl-37264342

RESUMO

BACKGROUND: Plant immunity relies on the perception of immunogenic signals by cell-surface and intracellular receptors and subsequent activation of defense responses like programmed cell death. Under certain circumstances, the fine-tuned innate immune system of plants results in the activation of autoimmune responses that cause constitutive defense responses and spontaneous cell death in the absence of pathogens. RESULTS: Here, we characterized the onset of leaf death 12 (old12) mutant that was identified in the Arabidopsis accession Landsberg erecta. The old12 mutant is characterized by a growth defect, spontaneous cell death, plant-defense gene activation, and early senescence. In addition, the old12 phenotype is temperature reversible, thereby exhibiting all characteristics of an autoimmune mutant. Mapping the mutated locus revealed that the old12 phenotype is caused by a mutation in the Lectin Receptor Kinase P2-TYPE PURINERGIC RECEPTOR 2 (P2K2) gene. Interestingly, the P2K2 allele from Landsberg erecta is conserved among Brassicaceae. P2K2 has been implicated in pathogen tolerance and sensing extracellular ATP. The constitutive activation of defense responses in old12 results in improved resistance against Pseudomonas syringae pv. tomato DC3000. CONCLUSION: We demonstrate that old12 is an auto-immune mutant and that allelic variation of P2K2 contributes to diversity in Arabidopsis immune responses.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Lectinas/genética , Lectinas/metabolismo , Resistência à Doença/fisiologia , Folhas de Planta/metabolismo , Mutação , Proteínas de Transporte/genética , Fenótipo , Receptores Mitogênicos/genética , Receptores Mitogênicos/metabolismo , Pseudomonas syringae/metabolismo , Doenças das Plantas/genética , Regulação da Expressão Gênica de Plantas
9.
Clin Rheumatol ; 42(8): 2125-2134, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37154983

RESUMO

INTRODUCTION/OBJECTIVES: The study aims to define the clinical and subclinical calcinosis prevalence, the sensitivity of radiographed site and clinical method for its diagnosis, and the phenotype of Portuguese systemic sclerosis (SSc) patients with calcinosis. METHOD: A cross-sectional multicenter study was conducted with SSc patients fulfilling Leroy/Medsger 2001 or ACR/EULAR 2013 classification criteria, registered in the Reuma.pt. Calcinosis was assessed through clinical examination and radiographs of hands, elbows, knees, and feet. Independent parametric or non-parametric tests, multivariate logistic regression, and sensitivity calculation of radiographed site and clinical method for calcinosis detection were performed. RESULTS: We included 226 patients. Clinical calcinosis was described in 63 (28.1%) and radiological calcinosis in 91 (40.3%) patients, of which 37 (40.7%) were subclinical. The most sensitive location to detect calcinosis was the hand (74.7%). Sensitivity of the clinical method was 58.2%. Calcinosis patients were more often female (p = 0.008) and older (p < 0.001) and had more frequently longer disease duration (p < 0.001), limited SSc (p = 0.017), telangiectasia (p = 0.039), digital ulcers (p = 0.001), esophageal (p < 0.001) and intestinal (p = 0.003) involvements, osteoporosis (p = 0.028), and late capillaroscopic pattern (p < 0.001). In multivariate analysis, digital ulcers (OR 2.63, 95% CI 1.02-6.78, p = 0.045) predicted overall calcinosis, esophageal involvement (OR 3.52, 95% CI 1.28-9.67, p = 0.015) and osteoporosis (OR 4.1, 95% CI 1.2-14.2, p = 0.027) predicted hand calcinosis, and late capillaroscopic pattern (OR 7.6, 95% CI 1.7-34.9, p = 0.009) predicted knee calcinosis. Anti-nuclear antibody positivity was associated with less knee calcinosis (OR 0.021, 95% CI 0.001-0477, p = 0.015). CONCLUSIONS: Subclinical calcinosis high prevalence suggests that calcinosis is underdiagnosed and radiographic screening might be relevant. Multifactorial pathogenesis may explain calcinosis predictors' variability. Key Points • Prevalence of subclinical calcinosis in SSc patients is substantial. • Hand radiographs are more sensitive to detect calcinosis than other locations or clinical method. • Digital ulcers were associated with overall calcinosis, esophageal involvement and osteoporosis were associated with hand calcinosis, and late sclerodermic pattern in nailfold capillaroscopy was associated with knee calcinosis. • Anti-nuclear antibody positivity may be a protective factor for knee calcinosis.


Assuntos
Calcinose , Osteoporose , Escleroderma Sistêmico , Feminino , Humanos , Estudos Transversais , Portugal , Calcinose/complicações , Calcinose/diagnóstico por imagem , Osteoporose/complicações
10.
Einstein (Sao Paulo) ; 21: eAO0109, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37132663

RESUMO

OBJECTIVE: To investigate the expression of human papillomavirus (HPV), p16, p53, and p63 in non-schistosomiasis-related squamous cell carcinoma of the bladder and to develop an accurate and automated tool to predict histological classification based on clinicopathological features. METHODS: Twenty-eight patients with primary bladder pure squamous cell carcinoma who underwent cystectomy or transurethral resection of bladder tumor (TURBT) for bladder cancer between January 2011 and July 2017 were evaluated. Clinical data and follow-up information were obtained from medical records. Formalin-fixed, paraffin-embedded surgical specimens were used for immunohistochemical staining for p16, p53, and p63. Human papillomavirus detection was evaluated by PCR. Statistical analysis was performed, and statistical significance was set at p<0.05. Finally, decision trees were built to classify patients' prognostic features. Leave-one-out cross-validation was used to test the generalizability of the model. RESULTS: Neither direct HPV detection nor its indirect marker (p16 protein) was identified in most cases. The absence of p16 was correlated with less aggressive histological grading (p=0.040). The positive p16 staining detection found only in pT1 and pT2 cases in our sample suggests a possible role for this tumor suppressor protein in the initial stages of bladder squamous cell carcinoma. The decision trees constructed described the relationship between clinical features, such as hematuria/dysuria, the level of tumor invasion, HPV status, lymphovascular invasion, gender, age, compromised lymph nodes, and tumor degree differentiation, with high classification accuracy. CONCLUSION: The algorithm classifier approach established decision pathways for semi-automatic tumor histological classification, laying the foundation for tailored semi-automated decision support systems for pathologists.


Assuntos
Carcinoma de Células Escamosas , Infecções por Papillomavirus , Neoplasias da Bexiga Urinária , Humanos , Papillomavirus Humano , Proteína Supressora de Tumor p53/metabolismo , Bexiga Urinária , Infecções por Papillomavirus/complicações , Carcinoma de Células Escamosas/patologia , Biomarcadores Tumorais/metabolismo , DNA Viral/análise
11.
Eur J Pharm Sci ; 187: 106470, 2023 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-37207942

RESUMO

Clofazimine (CFZ) is an important component of the World Health Organization's (WHO) recommended all-oral drug regimen for treatment of multi-drug resistant tuberculosis (MDR-TB). However, the lack of a dividable oral dosage form has limited the use of the drug in pediatric populations, who may require lowering of the dose to reduce the likelihood of adverse drug events. In this study, pediatric-friendly CFZ mini-tablets were prepared from micronized powder via direct compression. Rapid disintegration and maximized dissolution in GI fluids was achieved using an iterative formulation design process. Pharmacokinetic (PK) parameters of the optimized mini-tablets were obtained in Sprague-Dawley rats and compared against an oral suspension of micronized CFZ particles to examine the effect of processing and formulation on the oral absorption of the drug. Differences in maximum concentration and area under the curve between the two formulations were non-significant at the highest dosing level tested. Variability between rats prevented bioequivalence from being determined according to guidelines outlined by the Food and Drug Administration (FDA). These studies provide an important proof-of-concept for an alternative, low-cost formulation and processing approach for the oral delivery of CFZ in manner that is suitable for children as young as 6 months of age.


Assuntos
Tuberculose Resistente a Múltiplos Medicamentos , Tuberculose , Humanos , Criança , Animais , Ratos , Clofazimina/uso terapêutico , Ratos Sprague-Dawley , Tuberculose/tratamento farmacológico , Tuberculose Resistente a Múltiplos Medicamentos/tratamento farmacológico , Comprimidos
12.
Front Immunol ; 14: 1146817, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36969246

RESUMO

Objectives: Idiopathic inflammatory myopathies (IIM) are a group of rare disorders that can affect the heart. This work aimed to find predictors of cardiac involvement in IIM. Methods: Multicenter, open cohort study, including patients registered in the IIM module of the Rheumatic Diseases Portuguese Register (Reuma.pt/Myositis) until January 2022. Patients without cardiac involvement information were excluded. Myo(peri)carditis, dilated cardiomyopathy, conduction abnormalities, and/or premature coronary artery disease were considered. Results: 230 patients were included, 163 (70.9%) of whom were females. Thirteen patients (5.7%) had cardiac involvement. Compared with IIM patients without cardiac involvement, these patients had a lower bilateral manual muscle testing score (MMT) at the peak of muscle weakness [108.0 ± 55.0 vs 147.5 ± 22.0, p=0.008] and more frequently had oesophageal [6/12 (50.0%) vs 33/207 (15.9%), p=0.009] and lung [10/13 (76.9%) vs 68/216 (31.5%), p=0.001] involvements. Anti-SRP antibodies were more commonly identified in patients with cardiac involvement [3/11 (27.3%) vs 9/174 (5.2%), p=0.026]. In the multivariate analysis, positivity for anti-SRP antibodies (OR 104.3, 95% CI: 2.5-4277.8, p=0.014) was a predictor of cardiac involvement, regardless of sex, ethnicity, age at diagnosis, and lung involvement. Sensitivity analysis confirmed these results. Conclusion: Anti-SRP antibodies were predictors of cardiac involvement in our cohort of IIM patients, irrespective of demographical characteristics and lung involvement. We suggest considering frequent screening for heart involvement in anti-SRP-positive IIM patients.


Assuntos
Miocardite , Miosite , Doenças Reumáticas , Feminino , Humanos , Masculino , Estudos de Coortes , Coração
13.
Pharmaceutics ; 15(1)2023 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-36678803

RESUMO

The transport of drugs by efflux transporters in biomembranes limits their bioavailability and is a major determinant of drug resistance development by cancer cells and pathogens. A large number of chemically dissimilar drugs are transported, and despite extensive studies, the molecular determinants of substrate specificity are still not well understood. In this work, we explore the role of polar and non-polar interactions on the interaction of a homologous series of fluorescent amphiphiles with the efflux transporter P-glycoprotein. The interaction of the amphiphiles with P-glycoprotein is evaluated through effects on ATPase activity, efficiency in inhibition of [125I]-IAAP binding, and partition to the whole native membranes containing the transporter. The results were complemented with partition to model membranes with a representative lipid composition, and details on the interactions established were obtained from MD simulations. We show that when the total concentration of amphiphile is considered, the binding parameters obtained are apparent and do not reflect the affinity for P-gp. A new formalism is proposed that includes sequestration of the amphiphiles in the lipid bilayer and the possible binding of several molecules in P-gp's substrate-binding pocket. The intrinsic binding affinity thus obtained is essentially independent of amphiphile hydrophobicity, highlighting the importance of polar interactions. An increase in the lipophilicity and amphiphilicity led to a more efficient association with the lipid bilayer, which maintains the non-polar groups of the amphiphiles in the bilayer, while the polar groups interact with P-gp's binding pocket. The presence of several amphiphiles in this orientation is proposed as a mechanism for inhibition of P-pg function.

15.
J Clin Ultrasound ; 51(5): 837-844, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36715681

RESUMO

PURPOSE: To find ultrasound prognostic factors for shoulder pain. METHODS: This was an observational, prospective study, comparing the evolution of ultrasound findings with clinical outcomes, in patients with shoulder pain. Data were collected in two appointments, from February 2018 to March 2021. Two-tailed non-parametric statistics were used, and p values <0.05 were considered significant. RESULTS: A total of 79 participants were included in this study (median age 59 years, range 24-70, 61 women). A positive Doppler signal on tendons (p = 0.002) and absent tendon heterogeneity (p = 0.01) were associated with the patient's self-reported improvement. Tendon calcifications with poorly defined contours (p = 0.03) and sparse distribution (p = 0.001) were associated with VAS improvement. A reduction in the number of calcifications (p = 0.004), in the supraspinatus tendon thickness (p = 0.01), in subacromial effusions (p = 0.03), and in color Doppler grade (p = 0.02), between initial and follow-up exams, was found in patients with an improved DASH outcome. CONCLUSION: A positive Doppler signal on shoulder tendons can be a marker for a better prognosis in shoulder pain. Poorly defined and sparsely distributed calcifications can also indicate a better course of the disease.


Assuntos
Lesões do Manguito Rotador , Dor de Ombro , Humanos , Feminino , Adulto Jovem , Adulto , Dor de Ombro/diagnóstico por imagem , Estudos Prospectivos , Ombro , Manguito Rotador , Prognóstico
16.
Stem Cell Rev Rep ; 19(4): 906-927, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36585572

RESUMO

Hematopoietic stem cells are maintained in a specialized microenvironment, known as the 'niche', within the bone marrow. Understanding the contribution of cellular and molecular components within the bone marrow niche for the maintenance of hematopoietic stem cells is crucial for the success of therapeutic applications. So far, the roles of crucial mechanisms within the bone marrow niche have been explored in transgenic animals in which genetic modifications are ubiquitously introduced in the whole body. The lack of precise tools to explore genetic alterations exclusively within the bone marrow prevents our determination of whether the observed outcomes result from confounding effects from other organs. Here, we developed a new method - 'whole bone subcutaneous transplantation'- to study the bone marrow niche in transgenic animals precisely. Using immunolabeling of CD45.1 (donor) vs. CD45.2 (recipient) hematopoeitic stem cells, we demonstrated that hematopoeitic stem cells from the host animals colonize the subcutaneously transplanted femurs after transplantation, while the hematopoietic stem cells from the donor disappear. Strikinlgy, the bone marrow niche of these subcutaneously transplanted femurs remain from the donor mice, enabling us to study specifically cells of the bone marrow niche using this model. We also showed that genetic ablation of peri-arteriolar cells specifically in donor femurs reduced the numbers of hematopoietic stem cells in these bones. This supports the use of this strategy as a model, in combination with genetic tools, to evaluate how bone marrow niche specific modifications may impact non-modified hematopoietic stem cells. Thus, this approach can be utilized for genetic manipulation in vivo of specific cell types only within the bone marrow. The combination of whole bone subcutaneous transplantation with rodent transgenic models will facilitate a more precise, complex and comprehensive understanding of existing problems in the study of the hematopoietic stem cell bone marrow niche.


Assuntos
Medula Óssea , Transplante de Células-Tronco Hematopoéticas , Camundongos , Animais , Células-Tronco Hematopoéticas/metabolismo , Transplante de Medula Óssea , Osso e Ossos
17.
J Inorg Biochem ; 238: 112052, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36334365

RESUMO

The role of metal complexes on facing DNA has been a topic of major interest. However, metallonitrosyl compounds have been poorly investigated regarding their reactivities and interaction with DNA. A nitrosyl compound, cis-[Ru(bpy)2(SO3)(NO)](PF6)(A), showed a variety of promising biological activities catching our attention. Here, we carried out a series of studies involving the interaction and damage of DNA mediated by the metal complex A and its final product after NO release, cis-[Ru(bpy)2(SO3)(H2O](B). The fate of DNA with these metal complexes was investigated upon light or chemical stimuli using electrophoresis, electronic absorption spectroscopy, circular dichroism, size-exclusion resin, mass spectrometry, electron spin resonance (ESR) and viscometry. Since many biological disorders involve the production of oxidizing species, it is important to evaluate the reactivity of these compounds under such conditions as well. Indeed, the metal complex B exhibited important reactivity with H2O2 enabling DNA degradation, with detection of an unusual oxygenated intermediate. ESR spectroscopy detected mainly the DMPO-OOH adduct, which only emerges if H2O2 and O2 are present together. This result indicated HOO• as a key radical likely involved in DNA damage as supported by agarose gel electrophoresis. Notably, the nitrosyl ruthenium complex did not show evidence of direct DNA damage. However, its aqua product should be carefully considered as potentially harmful to DNA deserving further in vivo studies to better address any genotoxicity.


Assuntos
Complexos de Coordenação , Rutênio , Rutênio/química , Complexos de Coordenação/química , Peróxido de Hidrogênio , Compostos de Rutênio/química , Óxido Nítrico/química , DNA
18.
Einstein (Säo Paulo) ; 21: eAO0109, 2023. tab, graf
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1440060

RESUMO

ABSTRACT Objective To investigate the expression of human papillomavirus (HPV), p16, p53, and p63 in non-schistosomiasis-related squamous cell carcinoma of the bladder and to develop an accurate and automated tool to predict histological classification based on clinicopathological features. Methods Twenty-eight patients with primary bladder pure squamous cell carcinoma who underwent cystectomy or transurethral resection of bladder tumor (TURBT) for bladder cancer between January 2011 and July 2017 were evaluated. Clinical data and follow-up information were obtained from medical records. Formalin-fixed, paraffin-embedded surgical specimens were used for immunohistochemical staining for p16, p53, and p63. Human papillomavirus detection was evaluated by PCR. Statistical analysis was performed, and statistical significance was set at p<0.05. Finally, decision trees were built to classify patients' prognostic features. Leave-one-out cross-validation was used to test the generalizability of the model. Results Neither direct HPV detection nor its indirect marker (p16 protein) was identified in most cases. The absence of p16 was correlated with less aggressive histological grading (p=0.040). The positive p16 staining detection found only in pT1 and pT2 cases in our sample suggests a possible role for this tumor suppressor protein in the initial stages of bladder squamous cell carcinoma. The decision trees constructed described the relationship between clinical features, such as hematuria/dysuria, the level of tumor invasion, HPV status, lymphovascular invasion, gender, age, compromised lymph nodes, and tumor degree differentiation, with high classification accuracy. Conclusion The algorithm classifier approach established decision pathways for semi-automatic tumor histological classification, laying the foundation for tailored semi-automated decision support systems for pathologists.

19.
Front Pharmacol ; 14: 1328398, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38313072

RESUMO

Purinergic signaling has been implicated in many biological functions, including development. In this study, we investigate the functions of extracellular adenosine and adenosine receptors using a mouse embryonic stem cell (ESC) line and morula stages isolated from mouse embryos. Feeder-free mouse ESC was investigated in the absence and presence of the leukemia inhibitory factor (LIF), configuring undifferentiated cells and cells undergoing spontaneous differentiation. High alkaline phosphatase (ALPL) and low CD73 levels resulting in low adenosine (eADO) levels were characteristic for pluripotent cells in the presence of the LIF, while LIF deprivation resulted in augmented adenosine levels and reduced pluripotency marker expression, which indicated differentiation. Tracing ESC proliferation by BrdU labeling revealed that the inhibition of ALPL by levamisole resulted in a decrease in proliferation due to less eADO accumulation. Furthermore, caffeine and levamisole treatment, inhibiting adenosine receptor and eADO accumulation, respectively, reduced ESC migration, similar to that observed in the absence of the LIF. Pharmacological approaches of selective adenosine receptor subtype inhibition triggered specific adenosine receptor activities, thus triggering calcium or MAP kinase pathways leading to differentiation. In line with the in vitro data, mouse embryos at the morula stage were sensitive to treatments with A1 and A3 receptor antagonists, leading to the conclusion that A1 receptor and A3 receptor inhibition impairs proliferation and self-renewal and triggers inappropriate differentiation, respectively. The findings herein define the functions of eADO signaling in early development with implications for developmental disorders, in which adenosine receptors or ectonucleotidase dysfunctions are involved, and which could lead to malformations and miscarriages, due to exposure to caffeine.

20.
J. Health NPEPS ; 7(2): e6373, jul - dez, 2022. Saúde do Idoso
Artigo em Português | LILACS, BDENF - Enfermagem, Coleciona SUS | ID: biblio-1425602

RESUMO

Objetivo: relatar a experiência sobre a fundação, implementação, consolidação e ações de uma liga acadêmica interdisciplinar de gerontologia. Método: relato de experiência construído durante os meses de abril a maio de 2022 acerca da história e trajetória da Liga Acadêmica Interdisciplinar de Gerontologia da URI Santiago. Os dados que embasaram a escrita do relato de experiência foram extraídos do livro ata da Liga e das verbalizações dos integrantes. Resultados: fundar, implementar e consolidar uma Liga em tempos pandêmicos ascendeu uma maior responsabilidade na escolha da fundamentação teórica; fontes seguras para seleção; e na diversidade de conteúdos (complexidade do envelhecimento), em atenção às questões econômicas, sociais, culturais e de gênero que possuem relação direta com a saúde e a longevidade, sem esquecer da inclusão social (acesso e acessibilidade à tecnologia digital, literacia em saúde, territórios vulneráveis, condições individuais e familiares dos idosos). Conclusão: as atividades realizadas durante o percurso inicial da Liga, além de proporcionar aos discentes a autonomia em atuar de forma prática no contexto da gerontologia, despertou outros membros da comunidade acadêmica para o trabalho interdisciplinar e de engajamento.

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