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1.
Cancer Cell ; 42(3): 378-395.e10, 2024 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-38242126

RESUMO

Brain metastasis (BrM) is a common malignancy, predominantly originating from lung, melanoma, and breast cancers. The vasculature is a key component of the BrM tumor microenvironment with critical roles in regulating metastatic seeding and progression. However, the heterogeneity of the major BrM vascular components, namely endothelial and mural cells, is still poorly understood. We perform single-cell and bulk RNA-sequencing of sorted vascular cell types and detect multiple subtypes enriched specifically in BrM compared to non-tumor brain, including previously unrecognized immune regulatory subtypes. We integrate the human data with mouse models, creating a platform to interrogate vascular targets for the treatment of BrM. We find that the CD276 immune checkpoint molecule is significantly upregulated in the BrM vasculature, and anti-CD276 blocking antibodies prolonged survival in preclinical trials. This study provides important insights into the complex interactions between the vasculature, immune cells, and cancer cells, with translational relevance for designing therapeutic interventions.


Assuntos
Neoplasias Encefálicas , Neoplasias da Mama , Melanoma , Camundongos , Animais , Humanos , Feminino , Neoplasias Encefálicas/patologia , Encéfalo/metabolismo , Neoplasias da Mama/patologia , Fatores de Transcrição/metabolismo , Microambiente Tumoral , Antígenos B7
2.
Cerebellum ; 2023 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-38049694

RESUMO

Amyotrophic lateral sclerosis is a fatal neurodegenerative disorder that affects upper and lower motor neurons. SOD1 mutations are the second most commonly found in familial and sporadic cases. We describe a patient with a homozygous pathogenic mutation in SOD1 gene that presented with a progressive cerebellar ataxia and ultimately developed a complex phenotype of cerebellar ataxia and motor neuron disease. The linkage between the cerebellum and ALS is shortly discussed.

3.
Nat Immunol ; 24(10): 1645-1653, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37709986

RESUMO

Persistent exposure to antigen during chronic infection or cancer renders T cells dysfunctional. The molecular mechanisms regulating this state of exhaustion are thought to be common in infection and cancer, despite obvious differences in their microenvironments. Here we found that NFAT5, an NFAT family transcription factor that lacks an AP-1 docking site, was highly expressed in exhausted CD8+ T cells in the context of chronic infections and tumors but was selectively required in tumor-induced CD8+ T cell exhaustion. Overexpression of NFAT5 in CD8+ T cells reduced tumor control, while deletion of NFAT5 improved tumor control by promoting the accumulation of tumor-specific CD8+ T cells that had reduced expression of the exhaustion-associated proteins TOX and PD-1 and produced more cytokines, such as IFNÉ£ and TNF, than cells with wild-type levels of NFAT5, specifically in the precursor exhausted PD-1+TCF1+TIM-3-CD8+ T cell population. NFAT5 did not promote T cell exhaustion during chronic infection with clone 13 of lymphocytic choriomeningitis virus. Expression of NFAT5 was induced by TCR triggering, but its transcriptional activity was specific to the tumor microenvironment and required hyperosmolarity. Thus, NFAT5 promoted the exhaustion of CD8+ T cells in a tumor-selective fashion.


Assuntos
Coriomeningite Linfocítica , Neoplasias , Humanos , Fatores de Transcrição/metabolismo , Linfócitos T CD8-Positivos , Exaustão das Células T , Infecção Persistente , Microambiente Tumoral , Receptor de Morte Celular Programada 1/genética , Receptor de Morte Celular Programada 1/metabolismo , Vírus da Coriomeningite Linfocítica , Neoplasias/metabolismo
4.
Cell ; 186(21): 4546-4566.e27, 2023 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-37769657

RESUMO

Neutrophils are abundant immune cells in the circulation and frequently infiltrate tumors in substantial numbers. However, their precise functions in different cancer types remain incompletely understood, including in the brain microenvironment. We therefore investigated neutrophils in tumor tissue of glioma and brain metastasis patients, with matched peripheral blood, and herein describe the first in-depth analysis of neutrophil phenotypes and functions in these tissues. Orthogonal profiling strategies in humans and mice revealed that brain tumor-associated neutrophils (TANs) differ significantly from blood neutrophils and have a prolonged lifespan and immune-suppressive and pro-angiogenic capacity. TANs exhibit a distinct inflammatory signature, driven by a combination of soluble inflammatory mediators including tumor necrosis factor alpha (TNF-ɑ) and Ceruloplasmin, which is more pronounced in TANs from brain metastasis versus glioma. Myeloid cells, including tumor-associated macrophages, emerge at the core of this network of pro-inflammatory mediators, supporting the concept of a critical myeloid niche regulating overall immune suppression in human brain tumors.

6.
Nat Cancer ; 4(6): 908-924, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37217652

RESUMO

The immune-specialized environment of the healthy brain is tightly regulated to prevent excessive neuroinflammation. However, after cancer development, a tissue-specific conflict between brain-preserving immune suppression and tumor-directed immune activation may ensue. To interrogate potential roles of T cells in this process, we profiled these cells from individuals with primary or metastatic brain cancers via integrated analyses on the single-cell and bulk population levels. Our analysis revealed similarities and differences in T cell biology between individuals, with the most pronounced differences observed in a subgroup of individuals with brain metastasis, characterized by accumulation of CXCL13-expressing CD39+ potentially tumor-reactive T (pTRT) cells. In this subgroup, high pTRT cell abundance was comparable to that in primary lung cancer, whereas all other brain tumors had low levels, similar to primary breast cancer. These findings indicate that T cell-mediated tumor reactivity can occur in certain brain metastases and may inform stratification for treatment with immunotherapy.


Assuntos
Neoplasias Encefálicas , Linfócitos T , Humanos , Multiômica , Neoplasias Encefálicas/secundário , Encéfalo , Imunoterapia
7.
Case Rep Psychiatry ; 2023: 7960227, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36969133

RESUMO

Postictal psychosis (PIP) is one of the most common types of psychosis in epileptic patients. By virtue of the paucity of research on PIP, its pathophysiology remains not completely understood. Our case report describes a clinical picture of PIP, characterized by pleomorphic features, with neither Schneider's first-rank symptoms nor negative symptoms of schizophrenia, in a longstanding epileptic female patient with a history of nonadherence to antiepileptic treatment and poorly controlled seizures. Additionally, she had previous cognitive impairment and encephalomalacia in the right parietooccipital region as a sequela of a moderate-to-severe traumatic brain injury known to precede the emergence of the epilepsy. In light of our findings, we critically reviewed the current literature on postictal psychoses providing insight into its neurobiological underpinnings.

8.
Artigo em Inglês | MEDLINE | ID: mdl-36674293

RESUMO

Studying fatigue is challenging because it is influenced by physiological, psychological, and sociological states. Fatigue can be assessed objectively or subjectively, but the literature has difficulty understanding how an analytical test relates to a response via a questionnaire. Thus, the purpose of this study was to evaluate the relationships between objective fatigue variables (Squat Jump (SJ) and Countermovement Jump (CMJ)) measured on day-2 to the game and subjective fatigue (Rating Perceived Exertion (RPE) measured on day-3 to the game and Hooper Index (HI) measured on day-2). The sample comprised 32 professional football players from the First Portuguese League aged 25.86 ± 3.15 years. The Spearman correlations and regression analyses were used to study the relationships between the variables. The results showed statistically significant (p < 0.05) but small correlations (0.113−0.172) between several objective metrics and the subjective metrics evaluated. In addition, we found two weak models with statistical significance (p < 0.05) between the dependent objective variables (contact time, height, and elasticity index) and the HI (R2 = 3.7%) and RPE (R2 = 1.6%). Also, nine statistically significant (p < 0.05) but weak models were observed between the subjective dependent variables (HI and RPE) and contact time (R2 = 1.8−2.7%), flight time (R2 = 1.1−1.9%), height (R2 = 1.2−2.3%), power (R2 = 1.4%), pace (R2 = 1.2−2.1%), and elasticity index (R2 = 1.6%). In conclusion, objective and subjective fatigue-monitoring tests in professional soccer do not measure identical but rather complementary aspects of fatigue, and therefore, both need to be considered to gain a holistic perspective.


Assuntos
Futebol , Humanos , Fadiga/diagnóstico , Postura , Futebol/fisiologia
9.
Food Chem ; 402: 134463, 2023 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-36303366

RESUMO

Se in the form of sodium selenite was microencapsulated by spray - drying and added to a food matrix (yogurt) to study the potential improvement of its bioaccessibility. Yogurt samples were also supplemented with Se in free salt form. Se-loaded microparticles were successfully prepared by spray-drying with production yields above 70%. The supplementation of yogurt with Se in the form of free sodium selenite had a low effect on improving the bioaccessibility of this micronutrient (1%). In turn, Se microencapsulation with mannitol or mannitol/gastro-resistant polymer (Eudragit®) had a strong impact on bioaccessibility results. After the gastric phase, Se bioaccessibility reached values of 21 and 40% for the microencapsulated formulations, respectively. This percentage rose to 55% at the end of intestinal phase, showing no differences between both formulations. Our results show the relevance of microencapsulation as an effective tool to improve the bioaccessibility of micronutrients when they are used in food supplementation.


Assuntos
Selênio , Selenito de Sódio , Composição de Medicamentos/métodos , Suplementos Nutricionais , Micronutrientes , Manitol
10.
Front Immunol ; 14: 1335207, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38304252

RESUMO

The transforming growth factor-ß (TGF-ß) family member activin A (hereafter Activin-A) is overexpressed in many cancer types, often correlating with cancer-associated cachexia and poor prognosis. Activin-A secretion by melanoma cells indirectly impedes CD8+ T cell-mediated anti-tumor immunity and promotes resistance to immunotherapies, even though Activin-A can be proinflammatory in other contexts. To identify underlying mechanisms, we here analyzed the effect of Activin-A on syngeneic grafts of Braf mutant YUMM3.3 mouse melanoma cells and on their microenvironment using single-cell RNA sequencing. We found that the Activin-A-induced immune evasion was accompanied by a proinflammatory interferon signature across multiple cell types, and that the associated increase in tumor growth depended at least in part on pernicious STING activity within the melanoma cells. Besides corroborating a role for proinflammatory signals in facilitating immune evasion, our results suggest that STING holds considerable potential as a therapeutic target to mitigate tumor-promoting Activin-A signaling at least in melanoma.


Assuntos
Ativinas , Melanoma , Fator de Crescimento Transformador beta , Evasão Tumoral , Animais , Camundongos , Ativinas/metabolismo , Melanoma/imunologia , Transdução de Sinais , Fator de Crescimento Transformador beta/metabolismo , Microambiente Tumoral
11.
Heliyon ; 8(12): e11977, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36478795

RESUMO

Organizations heavily rely on information systems to improve their efficiency and effectiveness. However, on the one hand, information systems projects have often been seen as problematic endeavors. On the other hand, one can ask if this perspective results from subjective perceptions or objective assessments. We cannot find a definitive answer to this question in the literature. Moreover, there is no structured information about the models and methods currently available to assess projects' success in practice. This paper aims to present the results of a literature review carried out on the extant models and methods for evaluating the success of information systems projects. Additionally, it also offers models and methods from other areas that may be suitable for assessing IS projects. Results show that most models and methods found in the literature are, in their essence, theoretical exercises with only a few pieces of evidence of their use in practice, thus urging for more empirically based research.

12.
Percept Mot Skills ; 129(5): 1563-1580, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36028995

RESUMO

Sport performance depends in part on psychological factors. Self-determination theory emphasizes that the satisfisfaction of basic psychological needs and autonomous motivation may be linked to positive behavioral results and positive perceptions of performance. Our main objective in this study was to analyze the predictive power of such variables as perceived autonomy support, the satisfaction of psychological needs, and autonomous motivation on perceived sport performance. We recruited 447 young Portuguese athletes/participants (340 males, 107 females; Mage = 15.72 years, SD = 1.8). We had participants complete Portuguese sport versions of the Perceived Autonomy Support Exercise Climate Questionnaire, the Basic Psychological Needs in Exercise Scale, the Behavior Regulation Sport Questionnaire and the Perceived Performance in Sport Questionnaire. A gender invariant structural equation model showed that the coach's autonomy support significantly predicted the satisfaction of psychological needs for autonomy, competence, and relatedness. The satisfaction of these three psychological needs predicted autonomous motivation. Satisfying the need for competence positively predicted perceived sport performance, but autonomous motivation was not significantly related to perceived performance.


Assuntos
Autonomia Pessoal , Esportes , Atletas/psicologia , Feminino , Humanos , Masculino , Motivação , Satisfação Pessoal , Esportes/psicologia
13.
Curr Res Immunol ; 3: 1-12, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35496820

RESUMO

CD8 T cells have multiple functional properties that mediate acute phase and long-term immune protection. Several effector and memory CD8 T cell subsets have been described with diverse functionalities and marker profiles. In contrast to the many comprehensive mouse studies, most human studies lack samples from the acute infection phase, a major reason why current knowledge of human T cell subsets and differentiation remains incomplete, particularly with regard to the T cell heterogeneity early during the immune response. Here we analysed the human CD8 T cell response to yellow fever vaccination as the best-known model to study the human immune response to acute viral infection. We performed flow cytometry on 21 markers conventionally used in mice and in humans to describe differentiation, activation, cycling, and so-called effector functions. We found clearly distinct 'acute traits' at the peak of the response that are shared amongst all non-naïve antigen-specific subsets, including memory-differentiated cells. These acute traits were low BCL-2 and high KI67, CD38, HLA-DR, as well as increased Granzyme B and Perforin, previously attributed only to effector cells at the peak of the response. Furthermore, analysis of chromatin accessibility at the single cell level revealed that memory- and effector-differentiated cells clustered together specifically in the acute phase. Altogether, we demonstrate 'acute traits' across differentiation subsets, and point out the need to discriminate the differentiation states when studying human CD8 T cells that undergo an acute response.

14.
Radiol Case Rep ; 17(3): 1008-1012, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35111275

RESUMO

Whipple's disease is a rare chronic infectious disease, caused by Tropheryma whipplei. The disease can be challenging to diagnose due to the variable clinical manifestations and the nonspecific laboratory and imaging findings. We report the case of a 75-year-old man, complaining of weight loss and arthralgias with an insidious onset. A thoracic, abdominal and pelvic CT was performed, demonstrating features suggestive of Whipple's disease. Although not specific, the imaging findings of fatty attenuation mesenteric and retroperitoneal enlarged lymph nodes are a common finding in Whipple's disease. Esophagogastroduodenoscopy with duodenal biopsy confirmed the diagnosis through PCR analysis.

15.
Blood ; 139(16): 2483-2498, 2022 04 21.
Artigo em Inglês | MEDLINE | ID: mdl-35020836

RESUMO

NOTCH1 is a well-established lineage specifier for T cells and among the most frequently mutated genes throughout all subclasses of T cell acute lymphoblastic leukemia (T-ALL). How oncogenic NOTCH1 signaling launches a leukemia-prone chromatin landscape during T-ALL initiation is unknown. Here we demonstrate an essential role for the high-mobility-group transcription factor Tcf1 in orchestrating chromatin accessibility and topology, allowing aberrant Notch1 signaling to convey its oncogenic function. Although essential, Tcf1 is not sufficient to initiate leukemia. The formation of a leukemia-prone epigenetic landscape at the distal Notch1-regulated Myc enhancer, which is fundamental to this disease, is Tcf1-dependent and occurs within the earliest progenitor stage even before cells adopt a T lymphocyte or leukemic fate. Moreover, we discovered a unique evolutionarily conserved Tcf1-regulated enhancer element in the distal Myc-enhancer, which is important for the transition of preleukemic cells to full-blown disease.


Assuntos
Leucemia-Linfoma Linfoblástico de Células T Precursoras , Carcinogênese/genética , Linhagem Celular Tumoral , Cromatina/genética , Humanos , Oncogenes , Leucemia-Linfoma Linfoblástico de Células T Precursoras/genética , Receptor Notch1/genética
16.
Transl Anim Sci ; 5(4): txab199, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34729461

RESUMO

Heat stress negatively impacts production, reproduction, and health of ruminants and strategies to alleviate these losses are warranted. Therefore, four experiments evaluated different cooling strategies on vaginal temperature (VT) of Holstein × Gir cows. Experiment 1 compared different amounts of water (2- or 4-L) over a 1-hour period from 1000 to 1100 h and 1600 to 1700 h. Experiment 2 evaluated the effects of sprinkling duration (in hours; 1- or 2-H), whereas Experiment 3 evaluated the effects of water amount (4- or 8-L) applied for 1- or 2-H. Lastly, the effects of a cooling strategy on specific hours of the day, starting at either 0700 (T-1) or 1100 h (T-2; Experiment 4), were evaluated. In all experiments, 12 Holstein × Gir cows were used in a 2 × 2 Latin Square Design containing two periods of 6 days each. Temperature and humidity index (THI) were recorded hourly and VT was recorded every 10-min throughout the experiments. As expected, an hour effect was observed for THI (P < 0.0001), which peaked early in the afternoon. In Experiment 1, a treatment × hour interaction was observed (P < 0.0001) for VT, as animals assigned to receive 4-L had a reduced VT at 1100, 1600, 1700, and 2300 h (P ≤ 0.03). During the cooling applications, cows receiving 4-L for 1 h had a reduced VT from 60 to 150 min (P ≤ 0.04). In Experiment 2, a treatment × hour interaction was observed (P < 0.0001) for VT, as animals assigned to receive 4-L of water for 2-H had a reduced VT at 1200 h (P = 0.05). Moreover, during the cooling process, VT was reduced for 2-H cows from 140 to 170 min after the beginning of the cooling process (P ≤ 0.05). In Experiment 3, animals assigned to receive 4-L + 2H had a reduced VT at 1200, 1700, 1800, and 1900 h (P < 0.001). A treatment × hour interaction was observed (P < 0.0001), as VT was reduced for 4-L + 2-H cows from 130 to 180 min after the beginning of the cooling process (P ≤ 0.05). In Experiment 4, by the time when the first cooling cycle of T-1 was applied (0700 h), T-1 cows consistently had (P ≤ 0.05) a reduced VT up to the hottest hours and greatest THI of the day (1400 and 1500 h). This pattern was maintained until the end of the last cooling cycle, whereas T-2 cows had a reduced VT. In summary, 4 L of water over a 5-min cycle for a period of 2 hours twice a day maintained VT of Holstein × Gir cows at lower levels. Moreover, the hour at which the first cooling cycle starts also should be considered when evaluating the efficacy of a cooling strategy for an entire day.

17.
Nanomaterials (Basel) ; 11(10)2021 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-34684959

RESUMO

Dielectric properties and spectral dependence of the photocatalytic constant of Co doped P25 Degussa powder were studied. Doping of TiO2 matrix with cobalt was achieved by precipitation method using of Tris(diethylditiocarbamate)Co(III) precursor (CoDtc-Co[(C2H5)2NCS2]3). Five different Co contents with nominal Co/Ti atomic ratios of 0.005, 0.01, 0.02, 0.05 and 0.10 were chosen. Along with TiO2:Co samples, a few samples of nanopowders prepared by Sol-Gel method were also studied. As it follows from XPS and NMR studies, there is a concentration limit (TiO2:0.1Co) where cobalt atoms can be uniformly distributed across the TiO2 matrix before metallic clusters start to form. It was also shown that CoTiO3 phases are formed during annealing at high temperatures. From the temperature dependence of the dielectric constant it can be concluded that the relaxation processes still take place even at temperatures below 400 °C and that oxygen defect Ti-O octahedron reorientation take place at higher temperatures. The spectral dependency of the photocatalytic constant reveals the presence of some electronic states inside the energy gap of TiO2 for all nanopowdered samples.

18.
Foods ; 10(10)2021 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-34681413

RESUMO

A simple and rapid method for the quantitation of total fat in olive samples is designed, evaluated, and presented. This method is based on an innovative closed-vessel microwave-assisted extraction (MAE) technique. A method was designed for olives, and some figures of merits were evaluated: limit of detection (LOD), limit of quantification (LOQ) and expanded uncertainty (U). The data obtained in these experiences show that the workflow of the MAE method in a closed container is statistically equivalent to the other two methods, showing in this case better performance indicators (LOD = 0.02%, LOQ = 0.06%, and U = 15%). In addition, it is also demonstrated that the complete MAE method workflow allows the determination of total fat in a maximum of 12 analyses simultaneously for about 100 min in each run, which is the capacity of the rotor. This is a much better productivity when compared to the traditional Soxhlet-based method. Considering the sample workflow, the closed-vessel MAE method greatly simplifies sample handling, therefore minimizing sample loss during sample preparation and reducing analysis time. When MAE is compared to NIR-based methods, the advantage comes from there being no need for any type of calibration in the sample matrix. The MAE method itself can be used to determine the reference value for NIR calibration purposes. The results obtained for CRM using MAE were equivalent to the ones shown on the certificate.

19.
Prehosp Disaster Med ; 36(5): 651-653, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34470686

RESUMO

INTRODUCTION: The tropical cyclone Idai hit Mozambique in the city of Beira on March 15, 2019. During the following days, the Portuguese Emergency Medical Team (PT EMT) and its infrastructure deployed to Mozambique with the mission of helping local people and collaborating with the authorities. METHODS: Data analyzed were collected in the period of the deployment, from April 1-April 30, 2019. All patients admitted to PT EMT were registered through the Clinical Record of PT EMT. RESULTS: In total, 1,662 patients were admitted to PT EMT during the 30-day mission. The five most prevalent diagnoses were: 61.49% classified with "code 29" (which corresponds to "other unspecified diagnoses"), 9.15% of cases of skin disease, 8.90% of minor injuries, 6.74% of acute respiratory infection, and 3.19% of obstetric/genecology complications. DISCUSSION AND CHALLENGES: An important challenge identified was the need for a robust and effective network for transporting patients, allowing transfers between EMTs, enabling a true network response in the provision of care to disaster victims. CONCLUSIONS: The benefit of the deployment of PT EMT in Mozambique after Cyclone Idai was in line with the EMT initiative standards, allowing a direct delivery of care to the affected Mozambican population and support to the local health authorities.


Assuntos
Tempestades Ciclônicas , Missões Médicas , Etnicidade , Humanos , Moçambique , Portugal
20.
Life (Basel) ; 11(8)2021 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-34440597

RESUMO

The large production of non-degradable petrol-based plastics has become a major global issue due to its environmental pollution. Biopolymers produced by microorganisms such as polyhydroxyalkanoates (PHAs) are gaining potential as a sustainable alternative, but the high cost associated with their industrial production has been a limiting factor. Post-transcriptional regulation is a key step to control gene expression in changing environments and has been reported to play a major role in numerous cellular processes. However, limited reports are available concerning the regulation of PHA accumulation in bacteria, and many essential regulatory factors still need to be identified. Here, we review studies where the synthesis of PHA has been reported to be regulated at the post-transcriptional level, and we analyze the RNA-mediated networks involved. Finally, we discuss the forthcoming research on riboregulation, synthetic, and metabolic engineering which could lead to improved strategies for PHAs synthesis in industrial production, thereby reducing the costs currently associated with this procedure.

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