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1.
Proc Natl Acad Sci U S A ; 120(20): e2214853120, 2023 05 16.
Artigo em Inglês | MEDLINE | ID: mdl-37155874

RESUMO

Gastric cancer is a dominating cause of cancer-associated mortality with limited therapeutic options. Here, we show that syndecan-4 (SDC4), a transmembrane proteoglycan, is highly expressed in intestinal subtype gastric tumors and that this signature associates with patient poor survival. Further, we mechanistically demonstrate that SDC4 is a master regulator of gastric cancer cell motility and invasion. We also find that SDC4 decorated with heparan sulfate is efficiently sorted in extracellular vesicles (EVs). Interestingly, SDC4 in EVs regulates gastric cancer cell-derived EV organ distribution, uptake, and functional effects in recipient cells. Specifically, we show that SDC4 knockout disrupts the tropism of EVs for the common gastric cancer metastatic sites. Our findings set the basis for the molecular implications of SDC4 expression in gastric cancer cells and provide broader perspectives on the development of therapeutic strategies targeting the glycan-EV axis to limit tumor progression.


Assuntos
Neoplasias Gástricas , Sindecana-4 , Humanos , Heparitina Sulfato/metabolismo , Invasividade Neoplásica , Neoplasias Gástricas/genética , Sindecana-4/genética , Sindecana-4/metabolismo
2.
Clin Infect Dis ; 2024 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-38568992

RESUMO

BACKGROUND: In high-resource settings the survival of immunocompromised (IC) children has increased and immunosuppressive therapies are increasingly being used. This study aimed to determine the clinical characteristics, performance of diagnostic tools and outcome of IC children with TB in Europe. METHODS: Multicentre, matched case-control study within the Paediatric Tuberculosis Network European Trials Group (ptbnet), capturing TB cases <18 years diagnosed 2000-2020. RESULTS: 417 TB cases were included, comprising 139 children with IC (HIV, inborn errors of immunity, drug-induced immunosuppression and other immunocompromising conditions) and 278 non-IC children as controls. Non-respiratory TB was more frequent among cases than controls (32.4% vs. 21.2%; p = 0.013). IC patients had an increased likelihood of presenting with severe disease (57.6% vs. 38.5%; p < 0.001; OR [95% CI]: 2.073 [1.37-3.13]). Children with IC had higher rates of false-negative tuberculin skin test (31.9% vs. 6.0%; p < 0.001) and QuantiFERON-TB Gold assay (30.0% vs. 7.3%; p < 0.001) results at diagnosis. Overall, the microbiological confirmation rate was similar in IC and non-IC cases (58.3% vs. 49.3%; p = 0.083). Although the mortality in IC children was <1%, the rate of long-term sequelae was significantly higher than in non-IC cases (14.8% vs. 6.1%; p = 0.004). CONCLUSIONS: IC children with TB disease in Europe have increased rates of non-respiratory TB, severe disease, and long-term sequelae. Immune-based TB tests have poor sensitivity in those children. Future research should focus on developing improved immunological TB tests that perform better in IC patients, and determining the reasons for the increased risk of long-term sequelae, with the aim to design preventive management strategies.

3.
EMBO J ; 39(21): e103864, 2020 11 02.
Artigo em Inglês | MEDLINE | ID: mdl-32893934

RESUMO

The fragile X autosomal homolog 1 (Fxr1) is regulated by lithium and has been GWAS-associated with schizophrenia and insomnia. Homeostatic regulation of synaptic strength is essential for the maintenance of brain functions and involves both cell-autonomous and system-level processes such as sleep. We examined the contribution of Fxr1 to cell-autonomous homeostatic synaptic scaling and neuronal responses to sleep loss, using a combination of gene overexpression and Crispr/Cas9-mediated somatic knockouts to modulate gene expression. Our findings indicate that Fxr1 is downregulated during both scaling and sleep deprivation via a glycogen synthase kinase 3 beta (GSK3ß)-dependent mechanism. In both conditions, downregulation of Fxr1 is essential for the homeostatic modulation of surface AMPA receptors and synaptic strength. Preventing the downregulation of Fxr1 during sleep deprivation results in altered EEG signatures. Furthermore, sequencing of neuronal translatomes revealed the contribution of Fxr1 to changes induced by sleep deprivation. These findings uncover a role of Fxr1 as a shared signaling hub between cell-autonomous homeostatic plasticity and system-level responses to sleep loss, with potential implications for neuropsychiatric illnesses and treatments.


Assuntos
Homeostase/fisiologia , Proteínas de Ligação a RNA/genética , Proteínas de Ligação a RNA/metabolismo , Sono/genética , Sono/fisiologia , Animais , Encéfalo/fisiologia , Modelos Animais de Doenças , Regulação para Baixo , Regulação da Expressão Gênica , Técnicas de Inativação de Genes , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Plasticidade Neuronal , Neurônios/metabolismo , Receptores de AMPA/metabolismo , Transcriptoma
4.
J Med Genet ; 60(11): 1127-1132, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37055165

RESUMO

Rothmund-Thomson syndrome (RTS) is a rare, heterogeneous autosomal recessive genodermatosis, with poikiloderma as its hallmark. It is classified into two types: type I, with biallelic variants in ANAPC1 and juvenile cataracts, and type II, with biallelic variants in RECQL4, increased cancer risk and no cataracts. We report on six Brazilian probands and two siblings of Swiss/Portuguese ancestry presenting with severe short stature, widespread poikiloderma and congenital ocular anomalies. Genomic and functional analysis revealed compound heterozygosis for a deep intronic splicing variant in trans with loss of function variants in DNA2, with reduction of the protein levels and impaired DNA double-strand break repair. The intronic variant is shared by all patients, as well as the Portuguese father of the European siblings, indicating a probable founder effect. Biallelic variants in DNA2 were previously associated with microcephalic osteodysplastic primordial dwarfism. Although the individuals reported here present a similar growth pattern, the presence of poikiloderma and ocular anomalies is unique. Thus, we have broadened the phenotypical spectrum of DNA2 mutations, incorporating clinical characteristics of RTS. Although a clear genotype-phenotype correlation cannot be definitively established at this moment, we speculate that the residual activity of the splicing variant allele could be responsible for the distinct manifestations of DNA2-related syndromes.

5.
Nucleic Acids Res ; 50(9): e51, 2022 05 20.
Artigo em Inglês | MEDLINE | ID: mdl-35100398

RESUMO

Epigenome-wide association studies often detect many differentially methylated sites, and many are located in distal regulatory regions. To further prioritize these significant sites, there is a critical need to better understand the functional impact of CpG methylation. Recent studies demonstrated that CpG methylation-dependent transcriptional regulation is a widespread phenomenon. Here, we present MethReg, an R/Bioconductor package that analyzes matched DNA methylation and gene expression data, along with external transcription factor (TF) binding information, to evaluate, prioritize and annotate CpG sites with high regulatory potential. At these CpG sites, TF-target gene associations are often only present in a subset of samples with high (or low) methylation levels, so they can be missed by analyses that use all samples. Using colorectal cancer and Alzheimer's disease datasets, we show MethReg significantly enhances our understanding of the regulatory roles of DNA methylation in complex diseases.


Assuntos
Metilação de DNA , Epigênese Genética , Ilhas de CpG/genética , Metilação de DNA/genética , Estudo de Associação Genômica Ampla , Transcrição Gênica
6.
Mar Drugs ; 22(2)2024 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-38393026

RESUMO

Chondrosia reniformis is a collagen-rich marine sponge that is considered a sustainable and viable option for producing an alternative to mammalian-origin collagens. However, there is a lack of knowledge regarding the properties of collagen isolated from different sponge parts, namely the outer region, or cortex, (ectosome) and the inner region (choanosome), and how it affects the development of biomaterials. In this study, a brief histological analysis focusing on C. reniformis collagen spatial distribution and a comprehensive comparative analysis between collagen isolated from ectosome and choanosome are presented. The isolated collagen characterization was based on isolation yield, Fourier-transformed infrared spectroscopy (FTIR), circular dichroism (CD), SDS-PAGE, dot blot, and amino acid composition, as well as their cytocompatibility envisaging the development of future biomedical applications. An isolation yield of approximately 20% was similar for both sponge parts, as well as the FTIR, CD, and SDS-PAGE profiles, which demonstrated that both isolated collagens presented a high purity degree and preserved their triple helix and fibrillar conformation. Ectosome collagen had a higher OHpro content and possessed collagen type I and IV, while the choanosome was predominately constituted by collagen type IV. In vitro cytotoxicity assays using the L929 fibroblast cell line displayed a significant cytotoxic effect of choanosome collagen at 2 mg/mL, while ectosome collagen enhanced cell metabolism and proliferation, thus indicating the latter as being more suitable for the development of biomaterials. This research represents a unique comparative study of C. reniformis body parts, serving as a support for further establishing this marine sponge as a promising alternative collagen source for the future development of biomedical applications.


Assuntos
Micropartículas Derivadas de Células , Poríferos , Animais , Micropartículas Derivadas de Células/metabolismo , Materiais Biocompatíveis/farmacologia , Materiais Biocompatíveis/metabolismo , Poríferos/metabolismo , Colágeno/química , Colágeno Tipo I/metabolismo , Mamíferos/metabolismo
7.
Int J Biometeorol ; 68(5): 949-963, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38374295

RESUMO

In this initial study of a research project, this paper seeks to understand the thermal conditions in the cities of Lisbon and Munich, specifically focusing on Urban Heat Island intensity and on thermal comfort using the Universal Thermal Climate Index modeling data at the Local Climate Zone scale. Based on these datasets, Munich has exhibited more unfavourable thermal conditions than Lisbon. In terms of UHII, both cities have shown that low, medium, and high rise compact urban areas and bare rock or paved areas have the highest values, while sparsely built areas have the lowest. These results differ from the UTCI, which indicates that in Lisbon and Munich, these sparsely built areas as well as areas with low plants and vegetation are the most uncomfortable. In Munich, the population was exposed to very strong heat stress, while Lisbon experienced strong heat stress conditions. Conversely, low, medium, and high rise compact urban areas and densely wooded areas in Munich, and scattered trees areas and large low-rise urban areas in Lisbon, have demonstrated the lowest monthly mean and average maximum values. These results will be further explored in future studies in the city of Lisbon and cross-checked with data obtained from roving missions. This will enable a more detailed temporal and local analysis.


Assuntos
Cidades , Mudança Climática , Microclima , Humanos , Alemanha , Portugal , Modelos Teóricos , Sensação Térmica , Temperatura Alta
8.
Br J Community Nurs ; 29(3): 137-146, 2024 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-38421889

RESUMO

AIM: This study reviews research into the effects of the supplementation of B12 in the prevention and recovery of mental illness, and the potentiation of psychotropic medication. METHODOLOGY: This literature review follows a systematic approach to searching databases CINAHL, EMBASE, Medline, and PsycINFO where 287 non-duplicated articles results were received. Appropriate articles were identified through title and abstract screening and inclusion and exclusion criteria were applied. Five articles were chosen to address the research question following critical appraisal. Thematic analysis was then conducted. FINDINGS: This review identified five randomised controlled trials into the supplementation of various doses of B12 in conjunction with folic acid and B6. The supplement was measured against post-stroke depression prevention, the reduction of symptoms of depression in woman with cardiovascular disease, the effect on negative symptoms in schizophrenia, the reduction and prevention of depression in older adults, and the potentiation of psychotropic interventions. The papers reviewed showed inconclusive results, but evidence to support sub-groups and specific high-risk groups. Strong evidence showed supplementation of B12, folic acid and B6 has high rates of preventing post-stroke depression. CONCLUSION: The findings show that this area of research is still to be developed. The effects of B12 supplementation with other B vitamins on mental health have shown to be inconclusive. There is a case for its use to be considered within certain patient groups to aid recovery of mental health or in some high-risk patient groups. Recommendations are made for further research into high-risk groups of people that may have symptoms or symptoms that could be improved through the supplementation of B12.


Assuntos
Doenças Cardiovasculares , Vitamina B 12 , Feminino , Humanos , Idoso , Vitamina B 12/uso terapêutico , Ácido Fólico/uso terapêutico , Suplementos Nutricionais , Doenças Cardiovasculares/tratamento farmacológico , Avaliação de Resultados em Cuidados de Saúde
9.
Br J Community Nurs ; 29(2): 60-66, 2024 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-38300245

RESUMO

This article aims to provide an overview on loneliness in older people, with an emphasis on how insights from this body of literature can significantly contribute to the enhancement of care provided by community nurses. This review aims to provide a nuanced understanding of the factors contributing to loneliness, its impact on the physical and mental health of older individuals, and the role community nurses can play in mitigating and addressing loneliness.


Assuntos
Solidão , Saúde Mental , Humanos , Idoso
10.
Br J Nurs ; 33(5): 262-265, 2024 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-38446515

RESUMO

The term 'service user' is an amorphous concept that can refer to a variety of groups. It refers to people who use or have used a service, or to the carers or parents of service users, or it can be used to refer to lay people, the public or non-professionals. It can also be used to refer to all or any combination of these. To maximise the potential of simulation, it is crucial to involve service users: their inclusion in the co-design of simulations, alongside patient educators and participatory decision-makers, provides invaluable input from a patient perspective. They also make an important contribution by portraying patients in the scenarios within which students interact, providing perspectives based on real-life experiences, offering students an insight into how patients could respond. Such an approach to designing simulations as part of nursing education will help develop professionals who are more patient-centred, culturally competent and more responsive to patient needs.


Assuntos
Pais , Estudantes , Humanos , Simulação por Computador
11.
Thorax ; 78(3): 288-296, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36283826

RESUMO

RATIONALE: In 2016, a new interferon-gamma release assay (IGRA) was introduced, QuantiFERON-TB Gold Plus (QFT-Plus), claimed to have improved sensitivity in active tuberculosis (TB). OBJECTIVES: This study aimed to determine the performance of QFT-Plus, compared with previous generation IGRAs and the tuberculin skin test (TST), in children with TB in Europe. METHODS: Multicentre, ambispective cohort study within the Paediatric Tuberculosis Network European Trials Group (ptbnet), a dedicated paediatric TB research network comprising >300 members, capturing TB cases <18 years-of-age diagnosed between January 2009 and December 2019. MEASUREMENTS AND MAIN RESULTS: 1001 TB cases from 16 countries were included (mean age (IQR) 5.6 (2.4-12.1) years). QFT-Plus was performed in 358, QFT Gold in-Tube (QFT-GIT) in 600, T-SPOT.TB in 58 and TST in 636 cases. The overall test sensitivities were: QFT-Plus 83.8% (95% CI 80.2% to 87.8%), QFT-GIT 85.5% (95% CI 82.7% to 88.3%), T-SPOT.TB 77.6% (95% CI 66.9% to 88.3%) and TST (cut-off ≥10 mm) 83.3% (95% CI 83.3% to 86.2%). There was a trend for tests to have lower sensitivity in patients with miliary and/or central nervous system (CNS) TB (73.1%, 70.9%, 63.6% and 43.5%, respectively), and in immunocompromised patients (75.0%, 59.6%, 45.5% and 59.1%, respectively). CONCLUSIONS: The results indicate that the latest generation IGRA assay, QFT-Plus, does not perform better than previous generation IGRAs or the TST in children with TB disease. Overall, tests performed worse in CNS and miliary TB, and in immunocompromised children. None of the tests evaluated had sufficiently high sensitivity to be used as a rule-out test in children with suspected TB.


Assuntos
Tuberculose Latente , Tuberculose , Humanos , Criança , Pré-Escolar , Estudos de Coortes , Tuberculose/diagnóstico , Testes de Liberação de Interferon-gama/métodos , Teste Tuberculínico/métodos , Europa (Continente) , Tuberculose Latente/diagnóstico
12.
Clin Endocrinol (Oxf) ; 99(3): 335-341, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-36746771

RESUMO

OBJECTIVE: The clinical relevance of solid/trabecular (ST) growth in papillary thyroid carcinoma (PTC) is unclear. In this study, we investigated the impact of any amount of ST growth on tumour characteristics and patient outcomes. Furthermore, we evaluated whether ST growth per se affected patients' prognosis in the absence of aggressive features, namely vascular invasion. DESIGN: We analysed 222 PTC patients followed up for more than 5 years in the Department of Endocrinology of the Instituto Português de Oncologia de Lisboa Francisco Gentil from 2002 to 2020. All PTC cases with any percentage of ST growth were included and compared with PTC without ST growth (1:2). Carcinomas with high-grade features were excluded. RESULTS: There were 74 PTC cases with ST growth and 148 without ST growth (median follow-up of 9.3 years). PTC-ST was associated with larger tumour size (p = 0.001) and increased frequency of vascular invasion (p < 0.001) compared with PTC. However, PTC-ST did not exhibit a higher incidence of extrathyroidal extension (p = 1.000) or lymph node metastasis (p = 0.433). Despite the significantly higher prevalence of distant metastasis in PTC-ST compared with PTC (p = 0.043), the significance is lost when the cases with vascular invasion were excluded (p = 0.347). The total radioiodine activity was higher in PTC-ST than in PTC (p = 0.008). Recurrence rates were similar between groups (p = 0.755). The 10-year overall survival and disease-free survival rates for PTC-ST were 94.6% and 98.6%, respectively, similar to the PCT without ST growth (p = 0.097 and p = 0.333, respectively). There was no evidence of an association between the presence of an ST component (p = 0.201) with the risk of death or recurrence, whereas the presence of distant metastasis significantly increased the risk of these events (hazard ratio 10.14, p < 0.001). CONCLUSIONS: The presence of ST growth was associated with several aggressive clinicopathological features. However, the risk of cancer recurrence and death for PTC-ST were similar to PTC. In the absence of vascular invasion, the clinical impact of ST growth alone is negligible.


Assuntos
Carcinoma Papilar , Neoplasias da Glândula Tireoide , Humanos , Câncer Papilífero da Tireoide/cirurgia , Neoplasias da Glândula Tireoide/patologia , Relevância Clínica , Radioisótopos do Iodo , Carcinoma Papilar/patologia , Estudos Retrospectivos , Tireoidectomia , Recidiva Local de Neoplasia , Prognóstico
13.
Behav Pharmacol ; 34(5): 251-262, 2023 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-37401396

RESUMO

Here, we investigate the effects of obesity induced by monosodium glutamate (MSG) on cognitive impairment and whether this model induces any alteration in the affinity, density, and subtypes of muscarinic acetylcholine receptors (mAChRs) in rat hippocampus. Healthy rats were used as controls, and MSG-obese rats were selected via the Lee index > 0.300. The effects of MSG-induced obesity on hippocampal spatial learning and memory processes were evaluated by using the working memory versions of the Morris' water maze task and the evaluation of mAChRs by binding assay and their subtypes by immunoprecipitation assays. [ 3 H]Quinuclidinyl benzilate specific binding analysis showed that the equilibrium dissociation constant (K D ) did not differ between control and MSG, indicating that affinity is not affected by obesity induced by MSG. The maximum number of binding sites (B max ) obtained in MSG subjects was lower than that obtained from control rats, indicating a decrease in the expression of total mAChRs. Immunoprecipitation assays reveal a decrease in the expression of M 1 subtype of MSG when compared with control rats (M 2 to M 5 subtypes did not differ between control and MSG). We also observed that MSG promotes a disruption of the spatial working memory which was accompanied by a decrease in the M 1 mAChR subtype in rat hippocampus, thus suggesting deleterious long-term effects besides the obesity. In conclusion, these findings provide new insights into how obesity can influence spatial learning and memory that is hippocampal-dependent. The data suggest that the M 1 mAChR subtype protein expression is a potential therapeutic target.


Assuntos
Receptores Muscarínicos , Glutamato de Sódio , Ratos , Animais , Glutamato de Sódio/efeitos adversos , Glutamato de Sódio/metabolismo , Ratos Wistar , Receptores Muscarínicos/metabolismo , Obesidade , Hipocampo
14.
Brain ; 145(5): 1632-1640, 2022 06 03.
Artigo em Inglês | MEDLINE | ID: mdl-35661858

RESUMO

The axon initial segment is a specialized compartment of the proximal axon of CNS neurons where action potentials are initiated. However, it remains unknown whether this domain is assembled in sensory dorsal root ganglion neurons, in which spikes are initiated in the peripheral terminals. Here we investigate whether sensory neurons have an axon initial segment and if it contributes to spontaneous activity in neuropathic pain. Our results demonstrate that myelinated dorsal root ganglion neurons assemble an axon initial segment in the proximal region of their stem axon, enriched in the voltage-gated sodium channels Nav1.1 and Nav1.7. Using correlative immunofluorescence and calcium imaging, we demonstrate that the Nav1.7 channels at the axon initial segment are associated with spontaneous activity. Computer simulations further indicate that the axon initial segment plays a key role in the initiation of spontaneous discharges by lowering their voltage threshold. Finally, using a Cre-based mouse model for time-controlled axon initial segment disassembly, we demonstrate that this compartment is a major source of spontaneous discharges causing mechanical allodynia in neuropathic pain. Thus, an axon initial segment domain is present in sensory neurons and facilitates their spontaneous activity. This study provides a new insight in the cellular mechanisms that cause pathological pain and identifies a new potential target for chronic pain management.


Assuntos
Segmento Inicial do Axônio , Neuralgia , Animais , Gânglios Espinais/patologia , Humanos , Hiperalgesia/patologia , Camundongos , Neuralgia/patologia , Células Receptoras Sensoriais
15.
Nucleic Acids Res ; 49(16): 9246-9263, 2021 09 20.
Artigo em Inglês | MEDLINE | ID: mdl-34370013

RESUMO

To reconstruct systematically hyperactive transcription factor (TF)-dependent transcription networks in squamous cell carcinomas (SCCs), a computational method (ELMER) was applied to 1293 pan-SCC patient samples, and 44 hyperactive SCC TFs were identified. As a top candidate, DLX5 exhibits a notable bifurcate re-configuration of its bivalent promoter in cancer. Specifically, DLX5 maintains a bivalent state in normal tissues; its promoter is hypermethylation, leading to DLX5 transcriptional silencing in esophageal adenocarcinoma (EAC). In stark contrast, DLX5 promoter gains active histone marks and becomes transcriptionally activated in ESCC, which is directly mediated by SOX2. Functionally, silencing of DLX5 substantially inhibits SCC viability both in vitro and in vivo. Mechanistically, DLX5 cooperates with TP63 in regulating ∼2000 enhancers and promoters, which converge on activating cancer-promoting pathways. Together, our data establish a novel and strong SCC-promoting factor and elucidate a new epigenomic mechanism - bifurcate chromatin re-configuration - during cancer development.


Assuntos
Adenocarcinoma/genética , Carcinoma de Células Escamosas/genética , Neoplasias Esofágicas/genética , Proteínas de Homeodomínio/genética , Fatores de Transcrição/genética , Proteínas Supressoras de Tumor/genética , Adenocarcinoma/patologia , Animais , Carcinoma de Células Escamosas/patologia , Linhagem Celular Tumoral , Proliferação de Células/genética , Metilação de DNA/genética , Neoplasias Esofágicas/patologia , Feminino , Regulação Neoplásica da Expressão Gênica/genética , Xenoenxertos , Humanos , Masculino , Camundongos , Pessoa de Meia-Idade , Regiões Promotoras Genéticas/genética
16.
Mar Drugs ; 21(2)2023 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-36827098

RESUMO

The industrial processing of fish for food purposes also generates a considerable number of by-products such as viscera, bones, scales, and skin. From a value-added perspective, fish by-products can act also as raw materials, especially because of their collagen content (particularly in fish skin). Interestingly, the potential of marine collagen for cosmetic applications is enormous and, remarkably, the extraction of this protein from fish skins has been established for different species. Using this approach, we investigated the integration of marine collagen (COLRp_I) extracted from the skin of the Greenland halibut as an active ingredient in a cosmetic hydrogel formulation. In this study, extracts of marine collagen at concentrations up to 10 mg/mL showed a non-cytotoxic effect when cultured with fibroblast cells for 3 days. In addition, marine collagen extract, when incorporated into a cosmetic hydrogel formulation, met criterion A of ISO 11930:2019 regarding the efficacy of the preservative system (challenge test). In addition, the cosmetic formulations based on marine collagen at dosages of 0.1, 0.25 and 0.5% were tested in a clinical study on the skin of the forearms of 23 healthy volunteers, showing a sightly hydration effect, suggesting its potential for beauty applications. Moreover, this work illustrates that the circular economy concept applied to the fish processing industry can represent important benefits, at innovation, environmental and economic levels.


Assuntos
Cosméticos , Linguado , Animais , Groenlândia , Pele/metabolismo , Colágeno/metabolismo , Peixes
17.
Mar Drugs ; 21(2)2023 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-36827137

RESUMO

Arthropods, the largest animal phylum, including insects, spiders and crustaceans, are characterized by their bodies being covered primarily in chitin. Besides being a source of this biopolymer, crustaceans have also attracted attention from biotechnology given their cuticles' remarkable and diverse mechanical properties. The goose barnacle, Pollicipes pollicipes, is a sessile crustacean characterized by their body parts covered with calcified plates and a peduncle attached to a substrate covered with a cuticle. In this work, the composition and structure of these plates and cuticle were characterized. The morphology of the tergum plate revealed a compact homogeneous structure of calcium carbonate, a typical composition among marine invertebrate hard structures. The cuticle consisted of an outer zone covered with scales and an inner homogenous zone, predominantly organic, composed of successive layers parallel to the surface. The scales are similar to the tergum plate and are arranged in parallel and oriented semi-vertically. Structural and biochemical characterization confirmed a bulk composition of ɑ-chitin and suggested the presence of elastin-based proteins and collagen. The mechanical properties of the cuticle showed that the stiffness values are within the range of values described in elastomers and soft crustacean cuticles resulting from molting. The removal of calcified components exposed round holes, detailed the structure of the lamina, and changed the protein properties, increasing the rigidity of the material. This flexible cuticle, predominantly inorganic, can provide bioinspiration for developing biocompatible and mechanically suitable biomaterials for diverse applications, including in tissue engineering approaches.


Assuntos
Artrópodes , Thoracica , Animais , Thoracica/metabolismo , Quitina/química
18.
Mar Drugs ; 21(5)2023 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-37233496

RESUMO

Fucoidan has been reported to present diverse bioactivities, but each extract has specific features from which a particular biological activity, such as immunomodulation, must be confirmed. In this study a commercially available pharmaceutical-grade fucoidan extracted from Fucus vesiculosus, FE, was characterized and its anti-inflammatory potential was investigated. Fucose was the main monosaccharide (90 mol%) present in the studied FE, followed by uronic acids, galactose, and xylose that were present at similar values (3.8-2.4 mol%). FE showed a molecular weight of 70 kDa and a sulfate content of around 10%. The expression of cytokines by mouse bone-marrow-derived macrophages (BMDMs) revealed that the addition of FE upregulated the expression of CD206 and IL-10 by about 28 and 22 fold, respectively, in respect to control. This was corroborated in a stimulated pro-inflammatory situation, with the higher expression (60 fold) of iNOS being almost completely reversed by the addition of FE. FE was also capable of reverse LPS-caused inflammation in an in vivo mouse model, including by reducing macrophage activation by LPS from 41% of positive CD11C to 9% upon fucoidan injection. Taken together, the potential of FE as an anti-inflammatory agent was validated, both in vitro and in vivo.


Assuntos
Fucus , Camundongos , Animais , Lipopolissacarídeos , Polissacarídeos/farmacologia , Citocinas
19.
An Acad Bras Cienc ; 95(1): e20211348, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37075350

RESUMO

In this study we investigate the niche interaction between the frogs Physalameus cuvieri and Physalaemus kroyeri that occur in syntopy in water bodies of the Atlantic Forest located in the eastern Bahia State, Brazil. We investigated the niche width and overlap in the calling activity time, microhabitat use, diet composition, advertisement call, and body size. Both species preferred the same substrate and calling substrate categories, and showed low niche width values and high spatial niche overlap values. The pseudocommunity analysis revealed the absence of competition in space use. Ants and termites were the most important items in the diet of both species with the pseudocommunity analysis indicating an absence of competition in the diet. The two species demonstrate a greater similarity in body proportions and a high overlap in the calling activity time. However, they showed divergence in acoustic parameters, especially in the dominant frequency and call duration. Our results reinforce the role of advertisement call as a relevant attribute for anuran coexistence and highlight the importance of analyzing the various axes of the multidimensional niche for the most reliable description of the existence and magnitude of niche partitioning.


Assuntos
Anuros , Florestas , Animais , Brasil , Dieta , Acústica
20.
Mikrochim Acta ; 190(7): 273, 2023 Jun 23.
Artigo em Inglês | MEDLINE | ID: mdl-37351644

RESUMO

Contributing to the development of sustainable electroanalytical chemistry, electrochemically reduced graphene oxide (ERGO) films obtained from residual graphite of discharged Zn-C batteries are proposed in this work. Graphite from the cathode of discarded Zn-C batteries was recovered and used in the synthesis of graphene oxide (GO) by the modified Hummer's method. The quality of the synthesized GO was verified using different characterization methods (FT-IR, XRD, SEM, and TEM). GO films were deposited on a glassy carbon electrode (GCE) by the drop coating method and then electrochemically reduced by cathodic potential scanning using cyclic voltammetry. The electrochemical features of the ERGO films were investigated using the ferricyanide redox probe, as well as paracetamol (PAR) and hydroquinone (HQ) molecules as model analytes. From the cyclic voltammetry assays, enhanced heterogeneous electron transfer rate constants (k0) were observed for all redox systems studied. In analytical terms, the ERGO-based electrode showed higher analytical sensitivity than the bare and GO-modified GCE. Using differential pulse voltammetry, wide linear response ranges and limits of detection of 0.14 µmol L-1 and 0.65 µmol L-1 were achieved for PAR and HQ, respectively. Furthermore, the proposed sensor was successfully applied to the determination of PAR and HQ in synthetic urine and tap water samples (recoveries close to 100%). The outstanding electrochemical and analytical properties of the proposed ERGO films are added to the very low cost of the raw material, being presented as a green-based alternative for the development of electrochemical (bio)sensors with unsophisticated resources.


Assuntos
Grafite , Grafite/química , Acetaminofen , Hidroquinonas , Espectroscopia de Infravermelho com Transformada de Fourier , Técnicas Eletroquímicas/métodos , Carbono , Zinco
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