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2.
J Med Radiat Sci ; 2024 Jun 18.
Article in English | MEDLINE | ID: mdl-38888376

ABSTRACT

INTRODUCTION: Renal Point-of-Care Ultrasound (POCUS) is a screening modality that aids in clinical decision-making for patients with suspected renal colic. This study intends to compare the accuracy and pertinence of sonographic findings obtained by a sonographer in a Basic Emergency Service (BES) with the imaging findings at the Referral Hospital (RH). METHODS: Thirty-one patients suspected of having renal pathology underwent initial sonography screening with POCUS at the BES and were subsequently referred to the RH for additional imaging examinations. The results of both examinations were compared to verify whether the findings from the BES were confirmed by the radiologist in the RH and to ensure that the patient referrals from BES to RH were appropriate. RESULTS: In our sample, the majority of patients (80%) exhibited varying degrees of pyelocaliceal distension, with nearly half (48%) patients presenting obstructions. A strong association between the sonographic findings in the BES and the RH was found in the variables 'Dilatation of pyelocaliceal system' (V = 0.895; P = 0.00), 'Simple cystic formation' (V = 0.878; P = 0.000), respectively. There was a statistically significant correlation between BES and RH findings, indicating a strong association between these two variables, respectively (k = 0.890; P = 0.000) and (k = 0.870; P = 0.000). There was also a strong statistically significant correlation in the ultrasonographic findings between BES and RH performers (k = 0.890; P = 0.000 and k = 0.870; P = 0.000). In this research, an achieved sensitivity of 96% and a specificity of 85% were demonstrated in the identification of pyelocaliceal dilatation. CONCLUSION: Renal POCUS screening successfully detected abnormalities in the urinary system of patients suspected of having renal colic. The sonographic findings at the BES had a good correlation with the complementary imaging results obtained at the RH in Portugal. These results suggest that Radiographers/Sonographers can have an important role in the preliminary assessment of urgent renal pathology in remote areas, contributing to a correct referral and early treatment.

3.
Am J Cancer Res ; 14(5): 1999-2019, 2024.
Article in English | MEDLINE | ID: mdl-38859825

ABSTRACT

The effects of short-chain fatty acids (SCFAs) have been explored against cancer due to the crosstalk between gut microbiota alterations and the immune system as a crucial role in cancer development. We evaluated the SCFAs effects in both in vitro and in vivo breast cancer models. In vitro, the SCFAs displayed contrasting effects on viability index, according to the evaluation of breast cancer cells with different phenotypes, human MCF-7, SK-BR-3, MDA-MD-231, or the mouse 4T1 lineage. Acetate displayed minimal effects at concentrations up to 100 mM. Alternatively, propionate increases or reduces cell viability depending on the concentration. Butyrate and valerate showed consistent time- and concentration-dependent effects on the viability of human or mouse breast cancer cells. The selective FFA2 4-CMTB or FFA3 AR420626 receptor agonists failed to overtake the SCFA actions, except by modest inhibitory effects on MDA-MB-231 and 4T1 cell viability. The FFA2 CATPB or FFA3 and ß-hydroxybutyrate receptor antagonists lacked significant activity on human cell lines, although CATPB reduced 4T1 cell viability. Butyrate significantly affected cell morphology, clonogenicity, and migration, according to the evaluation of MDA-MB-231 and 4T1 cells. A preliminary examination of in vivo oral effects of butyrate, propionate, or valerate, dosed in prophylactic or therapeutic regimens, on several parameters evaluated in an orthotopic breast cancer model showed a reduction of lung metastasis in post-tumor induction butyrate-treated mice. Overall, the present results indicate that in vitro effects of SCFAs did not rely on FFA2 or FFA3 receptor activation, and they were not mirrored in vivo, at least at the tested conditions. Overall, the present results indicate potential in vitro inhibitory effects of SCFAs in breast cancer, independent of FFA2 or FFA3 receptor activation, and, in the metastatic breast cancer model, the butyrate-dosed therapeutic regimen reduced the number of lung metastases.

4.
J Neurovirol ; 2024 Jun 27.
Article in English | MEDLINE | ID: mdl-38935226

ABSTRACT

After the Zika virus (ZIKV) epidemic in Brazil, ZIKV infections were linked to damage to the central nervous system (CNS) and congenital anomalies. Due to the virus's ability to cross the placenta and reach brain tissue, its effects become severe, leading to Congenital Zika Syndrome (CZS) and resulting in neuroinflammation, microglial activation, and secretion of neurotoxic factors. The presence of ZIKV triggers an inadequate fetal immune response, as the fetus only has the protection of maternal antibodies of the Immunoglobulin G (IgG) class, which are the only antibodies capable of crossing the placenta. Because of limited understanding regarding the long term consequences of ZIKV infection and the involvement of maternal antibodies, this study sought to assess the impact of the ZIKV + IgG⁺complex on murine microglial cells. The cells were exposed to ZIKV, IgG antibodies, and the ZIKV + IgG⁺complex for 24 and 72 h. Treatment-induced cytotoxic effects were evaluated using the cell viability assay, oxidative stress, and mitochondrial membrane potential. The findings indicated that IgG antibodies exhibit cytotoxic effects on microglia, whether alone or in the presence of ZIKV, leading to compromised cell viability, disrupted mitochondrial membrane potential, and heightened oxidative damage. Our conclusion is that IgG antibodies exert detrimental effects on microglia, triggering their activation and potentially disrupting the creation of a neurotoxic environment. Moreover, the presence of antibodies may correlate with an elevated risk of ZIKV-induced neuroinflammation, contributing to long-term CNS damage.

5.
Rev. bras. cir. plást ; 39(2): 1-11, abr.jun.2024. ilus
Article in English, Portuguese | LILACS-Express | LILACS | ID: biblio-1556492

ABSTRACT

Introdução: A síntese de feridas de pele tensionadas é uma área que tem sido alvo de estudos para o desenvolvimento de técnicas de sutura que sejam capazes de realizar o fechamento primário dessas feridas com alívio de tensão, garantindo uma cicatrização adequada e evitando complicações como deiscência, edema, sangramento e infecção. Método: Esta pesquisa tratou-se de um estudo piloto, sendo a primeira apresentação da técnica de Sutura em Polia Retificada para síntese de feridas de pele tensionadas através do acompanhamento prospectivo, duplo-cego, de uma série de casos de 8 pacientes randomicamente admitidos no centro cirúrgico de um hospital de alta complexidade de uma cidade de médio porte. Resultados: A Sutura em Polia Retificada é uma técnica versátil e apta para lidar com feridas de pele tensionadas, uma vez que no intraoperatório conseguiu fechar por primeira intenção lesões de até 6,5 centímetros e de diferentes regiões tensionadas sem necessidade do uso de técnicas mais complexas, como retalhos, enxertos, zetaplastia e fechamento por segunda intenção. Além disso, no pós-operatório, houve redução dos escores da POSAS, indicando um processo de cicatrização satisfatório tanto para os observadores quanto para o paciente. É imprescindível mencionar, também, que o desfecho mais temido no seguimento dos pacientes com feridas tensionadas submetidos a fechamento primário - a deiscência - foi completamente evitado. Conclusão: A técnica é simples, confiável, segura e reprodutível, com curta curva de aprendizagem, de forma que a Sutura em Polia Retificada pode ser considerada como uma nova ferramenta a ser integrada ao arsenal cirúrgico.


Introduction: The synthesis of tensioned skin wounds is an area that has been the subject of studies for the development of suturing techniques that are capable of performing the primary closure of these wounds with tension relief, ensuring adequate healing, and avoiding complications such as dehiscence, edema, bleeding, and infection. Method: This research was a pilot study, being the first presentation of the Rectified Pulley Suture technique for the synthesis of tensioned skin wounds through prospective, double-blind monitoring of a series of cases of 8 patients randomly admitted to the surgical center of a high-complexity hospital in a mediumsized city. Results: Rectified Pulley Suture is a versatile technique suitable for dealing with tensioned skin wounds, since intraoperatively it was able to close, by first intention, lesions measuring up to 6.5 centimeters and in different tensioned regions without the need for the use of more extensive techniques. complex, such as flaps, grafts, Z-plasty, and secondary intention closure. Furthermore, post-operatively, there was a reduction in POSAS scores, indicating a satisfactory healing process for both observers and the patient. It is also essential to mention that the most feared outcome in the follow-up of patients with tension wounds undergoing primary closure - dehiscence - was completely avoided. Conclusion: The technique is simple, reliable, safe, and reproducible, with a short learning curve, so the Rectified Pulley Suture can be considered a new tool to be integrated into the surgical arsenal.

6.
Euro Surveill ; 29(18)2024 May.
Article in English | MEDLINE | ID: mdl-38699901

ABSTRACT

In March 2024, the first ever human case of rabies, following a dog bite, was detected in Timor-Leste. This paper briefly discusses the circumstances of transmission, clinical presentation, palliative care of the case and public health measures taken. Timor-Leste was previously considered rabies-free. Any person who is bitten or scratched by an animal that could potentially transmit rabies virus (especially dogs, bats, monkeys or cats) in Timor-Leste should be assessed for consideration of provision of rabies post-exposure prophylaxis.


Subject(s)
Bites and Stings , Post-Exposure Prophylaxis , Rabies virus , Rabies , Animals , Cats , Dogs , Female , Humans , Bites and Stings/virology , Chiroptera/virology , Rabies/diagnosis , Rabies/veterinary , Rabies/transmission , Rabies Vaccines/administration & dosage , Rabies virus/isolation & purification , Timor-Leste/epidemiology , Adolescent
7.
Eur J Hum Genet ; 32(7): 858-863, 2024 Jul.
Article in English | MEDLINE | ID: mdl-38778080

ABSTRACT

The ABC and ACMG variant classification systems were compared by asking mainly European clinical laboratories to classify variants in 10 challenging cases using both systems, and to state if the variant in question would be reported as a relevant result or not as a measure of clinical utility. In contrast to the ABC system, the ACMG system was not made to guide variant reporting but to determine the likelihood of pathogenicity. Nevertheless, this comparison is justified since the ACMG class determines variant reporting in many laboratories. Forty-three laboratories participated in the survey. In seven cases, the classification system used did not influence the reporting likelihood when variants labeled as "maybe report" after ACMG-based classification were included. In three cases of population frequent but disease-associated variants, there was a difference in favor of reporting after ABC classification. A possible reason is that ABC step C (standard variant comments) allows a variant to be reported in one clinical setting but not another, e.g., based on Bayesian-based likelihood calculation of clinical relevance. Finally, the selection of ACMG criteria was compared between 36 laboratories. When excluding criteria used by less than four laboratories (<10%), the average concordance rate was 46%. Taken together, ABC-based classification is more clear-cut than ACMG-based classification since molecular and clinical information is handled separately, and variant reporting can be adapted to the clinical question and phenotype. Furthermore, variants do not get a clinically inappropriate label, like pathogenic when not pathogenic in a clinical context, or variant of unknown significance when the significance is known.


Subject(s)
Genetic Variation , Humans , Genetic Testing/standards , Genetic Testing/methods
8.
Sci Rep ; 14(1): 10608, 2024 05 08.
Article in English | MEDLINE | ID: mdl-38719911

ABSTRACT

Over the last decades, monoclonal antibodies have substantially improved the treatment of several conditions. The continuous search for novel therapeutic targets and improvements in antibody's structure, demands for a constant optimization of their development. In this regard, modulation of an antibody's affinity to its target has been largely explored and culminated in the discovery and optimization of a variety of molecules. It involves the creation of antibody libraries and selection against the target of interest. In this work, we aimed at developing a novel protocol to be used for the affinity maturation of an antibody previously developed by our group. An antibody library was constructed using an in vivo random mutagenesis approach that, to our knowledge, has not been used before for antibody development. Then, a cell-based phage display selection protocol was designed to allow the fast and simple screening of antibody clones capable of being internalized by target cells. Next generation sequencing coupled with computer analysis provided an extensive characterization of the created library and post-selection pool, that can be used as a guide for future antibody development. With a single selection step, an enrichment in the mutated antibody library, given by a decrease in almost 50% in sequence diversity, was achieved, and structural information useful in the study of the antibody-target interaction in the future was obtained.


Subject(s)
Antibodies, Monoclonal , Antibody Affinity , Peptide Library , Humans , Antibodies, Monoclonal/immunology , Mutagenesis
9.
Orthod Craniofac Res ; 2024 May 07.
Article in English | MEDLINE | ID: mdl-38715428

ABSTRACT

INTRODUCTION: An ideal orthodontic treatment involves qualitative and quantitative measurements of dental and skeletal components to evaluate patients' discrepancies, such as facial, occlusal, and functional characteristics. Deciding between orthodontics and orthognathic surgery remains challenging, especially in borderline patients. Advances in technology are aiding clinical decisions in orthodontics. The increasing availability of data and the era of big data enable the use of artificial intelligence to guide clinicians' diagnoses. This study aims to test the capacity of different machine learning (ML) models to predict whether orthognathic surgery or orthodontics treatment is required, using soft and hard tissue cephalometric values. METHODS: A total of 920 lateral radiographs from patients previously treated with either conventional orthodontics or in combination with orthognathic surgery were used, comprising n = 558 Class II and n = 362 Class III patients, respectively. Thirty-two measures were obtained from each cephalogram at the initial appointment. The subjects were randomly divided into training (n = 552), validation (n = 183), and test (n = 185) datasets, both as an entire sample and divided into Class II and Class III sub-groups. The extracted data were evaluated using 10 machine learning models and by a four-expert panel consisting of orthodontists (n = 2) and surgeons (n = 2). RESULTS: The combined prediction of 10 models showed top-ranked performance in the testing dataset for accuracy, F1-score, and AUC (entire sample: 0.707, 0.706, 0.791; Class II: 0.759, 0.758, 0.824; Class III: 0.822, 0.807, 0.89). CONCLUSIONS: The proposed combined 10 ML approach model accurately predicted the need for orthognathic surgery, showing better performance in Class III patients.

10.
Cells ; 13(9)2024 Apr 25.
Article in English | MEDLINE | ID: mdl-38727281

ABSTRACT

This review delves into the groundbreaking impact of induced pluripotent stem cells (iPSCs) and three-dimensional organoid models in propelling forward neuropathology research. With a focus on neurodegenerative diseases, neuromotor disorders, and related conditions, iPSCs provide a platform for personalized disease modeling, holding significant potential for regenerative therapy and drug discovery. The adaptability of iPSCs, along with associated methodologies, enables the generation of various types of neural cell differentiations and their integration into three-dimensional organoid models, effectively replicating complex tissue structures in vitro. Key advancements in organoid and iPSC generation protocols, alongside the careful selection of donor cell types, are emphasized as critical steps in harnessing these technologies to mitigate tumorigenic risks and other hurdles. Encouragingly, iPSCs show promising outcomes in regenerative therapies, as evidenced by their successful application in animal models.


Subject(s)
Induced Pluripotent Stem Cells , Organoids , Organoids/pathology , Humans , Induced Pluripotent Stem Cells/cytology , Animals , Neuropathology/methods , Regenerative Medicine/methods , Neurodegenerative Diseases/therapy , Neurodegenerative Diseases/pathology , Cell Differentiation
11.
Biomedicines ; 12(5)2024 May 12.
Article in English | MEDLINE | ID: mdl-38791033

ABSTRACT

In our study, we investigated the prognostic significance of hematological markers-NLR (Neutrophil-to-Lymphocyte Ratio), PLR (Platelet-to-Lymphocyte Ratio), and RDW-CV (Red Blood Cell Distribution Width-Coefficient of Variation)-in 117 glioblastoma patients. The data collected from January 2016 to December 2018 included demographics, clinical scores, and treatment regimens. Unlike previous research, which often examined these markers solely before surgery, our unique approach analyzed them at multiple stages: preoperative, postoperative, and before adjuvant therapies. We correlated these markers with the overall survival (OS) and progression-free survival (PFS) using statistical tools, including ANOVA, Cox regression, and Kaplan-Meier survival analyses, employing SPSS version 29.0. Our findings revealed notable variations in the NLR, PLR, and RDW-CV across different treatment stages. The NLR and PLR decreased after surgery, with some stabilization post-STUPP phase (NLR: p = 0.007, η2p = 0.06; PLR: p = 0.001, η2p = 0.23), while the RDW-CV increased post-surgery and during subsequent treatments (RDW-CV: p < 0.001, η2p = 0.67). Importantly, we observed significant differences between the preoperative phase and other treatment phases. Additionally, a higher NLR and RDW-CV at the second-line treatment and disease progression were associated with an increased risk of death (NLR at 2nd line: HR = 1.03, p = 0.029; RDW-CV at progression: HR = 1.14, p = 0.004). We proposed specific marker cut-offs that demonstrated significant associations with survival outcomes when applied to Kaplan-Meier survival curves (NLR at 2nd line < 5: p < 0.017; RDW-CV at progression < 15: p = 0.007). An elevated NLR and RDW-CV at later treatment stages correlated with poorer OS and PFS. No significant preoperative differences were detected. These biomarkers may serve as non-invasive tools for glioblastoma management.

12.
Int J Clin Pharm ; 2024 May 11.
Article in English | MEDLINE | ID: mdl-38734866

ABSTRACT

BACKGROUND: Patient satisfaction has been positively associated with adherence which is expected to impact outcomes. Although vital for successful implementation of biosimilar medicines, little is known about the patient perspective of transition. AIM: The aim of this study was to investigate clinical outcomes and patient experience of transitioning between reference adalimumab and a biosimilar (SB5). METHOD: iBaSS is a phase IV single-centre, prospective, randomised, single-blind, cross-over study in adult subjects with Crohn's disease. Participants, stable on adalimumab before consent, received 24 weeks of treatment with both reference adalimumab and SB5. The primary outcome was the proportion of patients maintaining baseline clinical status throughout each treatment period, with patients' perspective of disease control and treatment satisfaction assessed as secondary outcomes. RESULTS: A total of 112 participants, representative of the heterogeneous patient populations encountered in routine clinical practice, were enrolled. A similar proportion of participants maintained baseline clinical status through each treatment period: 81.8% with reference adalimumab and 79.5% with SB5. Patient reported outcomes (IBD-Control questionnaire (SB5: 15.5; reference adalimumab 15) and TSQM), adverse events and therapeutic drug monitoring remained consistent through both treatment periods, although a higher median injection pain VAS score was noted with SB5 (53/100 versus 6/100 with reference adalimumab). The number of switches undertaken in the study did not impact serum drug concentration or immunogenicity. CONCLUSION: This study, mimicking real world adalimumab transition, demonstrates that patients undertaking brand transition can be expected to have consistent clinical and satisfaction outcomes. CLINICAL TRIAL REGISTERED WITH EUDRACT: Number 2018-004967-30.

13.
Cureus ; 16(3): e55775, 2024 Mar.
Article in English | MEDLINE | ID: mdl-38586751

ABSTRACT

The natural history and epidemiological aspects of traumatic cerebral venous thrombosis (CVT) are not fully understood. Due to the concomitant occurrence with intracranial hemorrhages, guidelines for medical treatment have been highly controversial. In this study, our objective was to carry out an analysis description of the population and to conduct a literature review. A prospectively gathered radiology registry data of patients hospitalized at the tertiary hospital of Centro Hospitalar Universitário do São João, Porto, Portugal, between 2016 and 2021 was carried out. All patients with traumatic brain injury (TBI) and concomitant CVT were identified. CVT was confirmed by CT venogram. Demographic, clinical, and radiological data and their medical management were reported. In-hospital complications and treatment outcomes were compared between patients measured by the Glasgow Outcome Score Extended (GOSE) at discharge and GOSE at three months. There were 41 patients with traumatic CVT admitted to this study. The majority (45.2%) had a hyperdense signal near the lateral sinus at admission, and only 26.2% presented with skull fractures. Of this cohort, 95% had experienced lateral sinus thrombosis. Twenty-five patients (60%) had occlusive venous thrombosis. Venous infarct was the main complication following CVT. Thirty-two patients (78%) were anticoagulated after CVT and four developed complications. At the three-month follow-up after discharge, 28.2% had good recovery (GOSE > 6). This study revealed a higher incidence of CVT in severe TBI and a mild association with skull fractures. There is a higher incidence of CVT in the lateral sinus. Management was inconsistent, with no difference in outcome without or with anticoagulation. Larger, prospective cohort studies are required to better comprehend this condition and determine evidence-based guidelines.

14.
Microorganisms ; 12(3)2024 Feb 28.
Article in English | MEDLINE | ID: mdl-38543539

ABSTRACT

The success of the intracellular parasite Toxoplasma gondii in invading host cells relies on the apical complex, a specialized microtubule cytoskeleton structure associated with secretory organelles. The T. gondii genome encodes three isoforms of both α- and ß-tubulin, which undergo specific post-translational modifications (PTMs), altering the biochemical and biophysical proprieties of microtubules and modulating their interaction with associated proteins. Tubulin PTMs represent a powerful and evolutionarily conserved mechanism for generating tubulin diversity, forming a biochemical 'tubulin code' interpretable by microtubule-interacting factors. T. gondii exhibits various tubulin PTMs, including α-tubulin acetylation, α-tubulin detyrosination, Δ5α-tubulin, Δ2α-tubulin, α- and ß-tubulin polyglutamylation, and α- and ß-tubulin methylation. Tubulin glutamylation emerges as a key player in microtubule remodeling in Toxoplasma, regulating stability, dynamics, interaction with motor proteins, and severing enzymes. The balance of tubulin glutamylation is maintained through the coordinated action of polyglutamylases and deglutamylating enzymes. This work reviews and discusses current knowledge on T. gondii tubulin glutamylation. Through in silico identification of protein orthologs, we update the recognition of putative proteins related to glutamylation, contributing to a deeper understanding of its role in T. gondii biology.

15.
Korean J Orthod ; 54(2): 128-135, 2024 Mar 25.
Article in English | MEDLINE | ID: mdl-38533600

ABSTRACT

Objective: : The number of three-piece maxillary osteotomies has increased over the years; however, the literature remains controversial. The objective of this study was to evaluate the skeletal stability of this surgical modality compared with that of one-piece maxillary osteotomy. Methods: : This retrospective cohort study included 39 individuals who underwent Le Fort I maxillary osteotomies and were divided into two groups: group 1 (three pieces, n = 22) and group 2 (one piece, n = 17). Three cone-beam computed tomography scans from each patient (T1, pre-surgical; T2, post-surgical; and T3, follow-up) were used to evaluate the three-dimensional skeletal changes. Results: : The differences within groups were statistically significant only for group 1 in terms of surgical changes (T2-T1) with a mean difference in the canine region of 3.09 mm and the posterior region of 3.08 mm. No significant differences in surgical stability were identified between or within the groups. The mean values of the differences between groups were 0.05 mm (posterior region) and -0.39 mm (canine region). Conclusions: : Our findings suggest that one- and three-piece maxillary osteotomies result in similar post-surgical skeletal stability.

16.
Pharmaceutics ; 16(2)2024 Jan 29.
Article in English | MEDLINE | ID: mdl-38399250

ABSTRACT

The potential emergence of zoonotic diseases has raised significant concerns, particularly in light of the recent pandemic, emphasizing the urgent need for scientific preparedness. The bioprospection and characterization of new molecules are strategically relevant to the research and development of innovative drugs for viral and bacterial treatment and disease management. Amphibian species possess a diverse array of compounds, including antimicrobial peptides. This study identified the first bioactive peptide from Salamandra salamandra in a transcriptome analysis. The synthetic peptide sequence, which belongs to the defensin family, was characterized through MALDI TOF/TOF mass spectrometry. Molecular docking assays hypothesized the interaction between the identified peptide and the active binding site of the spike WT RBD/hACE2 complex. Although additional studies are required, the preliminary evaluation of the antiviral potential of synthetic SS-I was conducted through an in vitro cell-based SARS-CoV-2 infection assay. Additionally, the cytotoxic and hemolytic effects of the synthesized peptide were assessed. These preliminary findings highlighted the potential of SS-I as a chemical scaffold for drug development against COVID-19, hindering viral infection. The peptide demonstrated hemolytic activity while not exhibiting cytotoxicity at the antiviral concentration.

17.
Nanoscale Adv ; 6(5): 1486-1496, 2024 Feb 27.
Article in English | MEDLINE | ID: mdl-38419868

ABSTRACT

Luminescent nanoparticles have shown great potential for thermal sensing in bio-applications. Nonetheless, these materials lack water dispersibility that can be overcome by modifying their surface properties with water dispersible molecules such as cysteine. Herein, we employ LiYF4:Er3+/Yb3+ upconverting nanoparticles (UCNPs) capped with oleate or modified with cysteine dispersed in cyclohexane or in water, respectively, as thermal probes. Upconversion emission was used to sense temperature with a relative thermal sensitivity of ∼1.24% K-1 (at 300 K) and a temperature uncertainty of 0.8 K for the oleate capped and of 0.5 K for cysteine modified NPs. To study the effect of the cysteine modification in the heat transfer processes, the thermal conductivity of the nanofluids was determined, yielding 0.123(6) W m-1 K-1 for the oleate capped UCNPs dispersed in cyclohexane and 0.50(7) W m-1 K-1 for the cysteine modified UCNPs dispersed in water. Moreover, through the heating curves, the nanofluids' thermal resistances were estimated, showing that the cysteine modification partially prevents heat transfer.

18.
Biochem Soc Trans ; 52(1): 279-289, 2024 Feb 28.
Article in English | MEDLINE | ID: mdl-38385536

ABSTRACT

Diet is currently recognized as a major modifiable agent of human health. In particular, dietary nitrate has been increasingly explored as a strategy to modulate different physiological mechanisms with demonstrated benefits in multiple organs, including gastrointestinal, cardiovascular, metabolic, and endocrine systems. An intriguing exception in this scenario has been the brain, for which the evidence of the nitrate benefits remains controversial. Upon consumption, nitrate can undergo sequential reduction reactions in vivo to produce nitric oxide (•NO), a ubiquitous paracrine messenger that supports multiple physiological events such as vasodilation and neuromodulation. In the brain, •NO plays a key role in neurovascular coupling, a fine process associated with the dynamic regulation of cerebral blood flow matching the metabolic needs of neurons and crucial for sustaining brain function. Neurovascular coupling dysregulation has been associated with neurodegeneration and cognitive dysfunction during different pathological conditions and aging. We discuss the potential biological action of nitrate on brain health, concerning the molecular mechanisms underpinning this association, particularly via modulation of •NO-dependent neurovascular coupling. The impact of nitrate supplementation on cognitive performance was scrutinized through preclinical and clinical data, suggesting that intervention length and the health condition of the participants are determinants of the outcome. Also, it stresses the need for multimodal quantitative studies relating cellular and mechanistic approaches to function coupled with behavior clinical outputs to understand whether a mechanistic relationship between dietary nitrate and cognitive health is operative in the brain. If proven, it supports the exciting hypothesis of cognitive enhancement via diet.


Subject(s)
Neurovascular Coupling , Humans , Neurovascular Coupling/physiology , Nitrates/pharmacology , Nitric Oxide/metabolism , Dietary Supplements , Cognition
19.
Rev Port Cardiol ; 43(6): 311-320, 2024 Jun.
Article in English, Portuguese | MEDLINE | ID: mdl-38401703

ABSTRACT

INTRODUCTION AND OBJECTIVES: Aortic stenosis is the most common valvular heart disease. The number of octogenarians proposed for intervention is growing due to increased lifespan. In this manuscript we aim to evaluate perioperative outcome and long-term survival after surgical aortic valve replacement (SAVR) in octogenarians, comparing patients with low surgical risk (EuroscoreII <4%) with intermediate-high risk (EuroscoreII ≥4%). METHODS: A retrospective observational single-center cohort study with 195 patients aged ≥80 years old, who underwent SAVR between 2017 and 2021, was conducted. Patients were divided into two groups according to EuroscoreII: (1) Low risk (EuroscoreII <4%) with intermediate-high risk (EuroscoreII ≥4%). Continuous variables are presented in median (IQR), analyzed using Wilcoxon rank sum test; categorical variables in percentages, analyzed using chi-squared test; and survival was analyzed by Kaplan-Meier, open cohort, and the log-rank test was performed. RESULTS: The overall median age was 82 (IQR 81-83), with 4.6% of the patients ≥85 years old. 23.6% of the patients presented EuroscoreII ≥4%. No complications were observed in 26.2%, with a significantly higher rate in intermediate-high risk patients. Postoperative need for hemodynamic support was the most frequent complication, followed by postoperative acute kidney injury and the use of blood products. Overall median ICU stay was three days (2-4) and hospital length of stay (LOS) six days (5-8). Patients with intermediate-high risk and those with complications had longer ICU LOS. At 12 months, overall survival was 96.4%, at three years 94.1% and 5 years 75.4%. Patients with low surgical risk had higher survival proportions up to 5 years. CONCLUSION: SAVR in patients ≥80 years is associated with low in-hospital mortality, although a significant proportion of patients develop complications. Long-term follow-up up to five years after surgery is acceptable in octogenarians with low surgical risk.


Subject(s)
Aortic Valve Stenosis , Heart Valve Prosthesis Implantation , Humans , Retrospective Studies , Female , Male , Aged, 80 and over , Aortic Valve Stenosis/surgery , Aortic Valve Stenosis/mortality , Heart Valve Prosthesis Implantation/mortality , Time Factors , Treatment Outcome , Survival Rate , Cohort Studies , Aortic Valve/surgery
20.
Org Biomol Chem ; 22(11): 2252-2263, 2024 03 13.
Article in English | MEDLINE | ID: mdl-38390694

ABSTRACT

Monitoring cell viability is critical in cell biology, pathology, and drug discovery. Most cell viability assays are cell-destructive, time-consuming, expensive, and/or hazardous. Herein, we present a series of newly synthesized 2,4,5-triaminopyrimidine derivatives able to discriminate between live and dead cells. To our knowledge, these compounds are the first fluorescent nucleobase analogues (FNAs) with cell viability monitoring potential. These new fluorescent molecules are synthesized using highly efficient and cost-effective methods and feature unprecedented photophysical properties (longer absorption and emission wavelengths, environment-sensitive emission, and unprecedented brightness within FNAs). Using a live-dead Saccharomyces cerevisiae cell and theoretical assays, the fluorescent 2,4,5-triaminopyrimidine derivatives were found to specifically accumulate inside dead cells by interacting with dsDNA grooves, thus paving the way for the emergence of novel and safe fluorescent cell viability markers emitting in the blue region. As the majority of commercially available viability dyes emit in the green to red region of the visible spectrum, these novel markers might be useful to meet the needs of blue markers for co-staining combinations.


Subject(s)
Fluorescent Dyes , Microscopy , Cell Survival
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