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1.
Exp Cell Res ; 440(2): 114136, 2024 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-38909881

RESUMO

Considering the importance of alternative methodologies to animal experimentation, we propose an organoid-based biological model for in vitro blood vessel generation, achieved through co-culturing endothelial and vascular smooth muscle cells (VSMCs). Initially, the organoids underwent comprehensive characterization, revealing VSMCs (α-SMA + cells) at the periphery and endothelial cells (CD31+ cells) at the core. Additionally, ephrin B2 and ephrin B4, genes implicated in arterial and venous formation respectively, were used to validate the obtained organoid. Moreover, the data indicates exclusive HIF-1α expression in VSMCs, identified through various methodologies. Subsequently, we tested the hypothesis that the generated blood vessels have the capacity to modulate the osteogenic phenotype, demonstrating the ability of HIF-1α to promote osteogenic signals, primarily by influencing Runx2 expression. Overall, this study underscores that the methodology employed to create blood vessel organoids establishes an experimental framework capable of producing a 3D culture model of both venous and arterial endothelial tissues. This model effectively guides morphogenesis from mesenchymal stem cells through paracrine signaling, ultimately leading to an osteogenic acquisition phenotype, with the dynamic involvement of HIF-1α.

2.
Cell Biol Int ; 2024 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-38591759

RESUMO

During the morphological changes occurring in osteoblast differentiation, Sonic hedgehog (Shh) plays a crucial role. While some progress has been made in understanding this process, the epigenetic mechanisms governing the expression of Hh signaling members in response to bone morphogenetic protein 7 (BMP7) signaling in osteoblasts remain poorly understood. To delve deeper into this issue, we treated pre-osteoblasts (pObs) with 100 ng/mL of BMP7 for up to 21 days. Initially, we validated the osteogenic phenotype by confirming elevated expression of well-defined gene biomarkers, including Runx2, Osterix, Alkaline Phosphatase (Alp), and bone sialoprotein (Bsp). Simultaneously, Hh signaling-related members Sonic (Shh), Indian (Ihh), and Desert (Dhh) Hedgehog (Hh) exhibited nuanced modulation over the 21 days in vitro period. Subsequently, we evaluated epigenetic markers, and our data revealed a notable change in the CpG methylation profile, considering the methylation/hydroxymethylation ratio. CpG methylation is a reversible process regulated by DNA methyltransferases and demethylases, including Ten-eleven translocation (Tets), which also exhibited changes during the acquisition of the osteogenic phenotype. Specifically, we measured the methylation pattern of Shh-related genes and demonstrated a positive Pearson correlation for GLI Family Zinc Finger 1 (Gli1) and Patched (Ptch1). This data underscores the significance of the epigenetic machinery in modulating the BMP7-induced osteogenic phenotype by influencing the activity of Shh-related genes. In conclusion, this study highlights the positive impact of epigenetic control on the expression of genes related to hedgehog signaling during the morphogenetic changes induced by BMP7 signaling in osteoblasts.

3.
Cell Biol Int ; 48(5): 665-681, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38420868

RESUMO

Epigenetic changes, particularly histone compaction modifications, have emerged as critical regulators in the epigenetic pathway driving endothelial cell phenotype under constant exposure to laminar forces induced by blood flow. However, the underlying epigenetic mechanisms governing endothelial cell behavior in this context remain poorly understood. To address this knowledge gap, we conducted in vitro experiments using human umbilical vein endothelial cells subjected to various tensional forces simulating pathophysiological blood flow shear stress conditions, ranging from normotensive to hypertensive forces. Our study uncovers a noteworthy observation wherein endothelial cells exposed to high shear stress demonstrate a decrease in the epigenetic marks H3K4ac and H3K27ac, accompanied by significant alterations in the levels of HDAC (histone deacetylase) proteins. Moreover, we demonstrate a negative regulatory effect of increased shear stress on HOXA13 gene expression and a concomitant increase in the expression of the long noncoding RNA, HOTTIP, suggesting a direct association with the suppression of HOXA13. Collectively, these findings represent the first evidence of the role of histone-related epigenetic modifications in modulating chromatin compaction during mechanosignaling of endothelial cells in response to elevated shear stress forces. Additionally, our results highlight the importance of understanding the physiological role of HOXA13 in vascular biology and hypertensive patients, emphasizing the potential for developing small molecules to modulate its activity. These findings warrant further preclinical investigations and open new avenues for therapeutic interventions targeting epigenetic mechanisms in hypertensive conditions.


Assuntos
Epigênese Genética , Histonas , Humanos , Histonas/metabolismo , Células Endoteliais da Veia Umbilical Humana/metabolismo , Hemodinâmica , Estresse Mecânico , Células Cultivadas
4.
Rapid Commun Mass Spectrom ; 38(12): e9739, 2024 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-38605205

RESUMO

RATIONALE: 4,7-Dichloroquinoline (DCQ) represents a group of synthetic molecules inspired by natural products with important roles in biological and biomedical areas. This work aimed to characterize DCQ and its derivatives by high-resolution electrospray ionization (ESI) mass spectrometry and tandem mass spectrometry (ESI-MS/MS), supported by theoretical calculations. Biological assays were carried out with DCQ and its derivatives to determine LC50 values against Aedes aegypti larvae. METHODS: Five DCQ derivatives were synthesized by using previously described protocols. ESI-MS/MS analyses were carried out with a quadrupole/time-of-flight and ion-trap instrument. The proposed gas-phase protonation sites and fragmentation were supported by density functional theory calculations. The larvicidal tests were performed with the Ae. aegypti Rockefeller strain, and the LC50 values were determined by employing five test concentrations. Larval mortality was determined after treatment for 48 h. RESULTS: DCQ bromides or aldehydes (C-3 or C-8 positions), as well as the trimethylsilyl derivative (C-3 position), were prepared. Detailed ESI-MS/MS data revealed heteroatom elimination through an exception to the even-electron rule, to originate open-shell species. Computational studies were used to define the protonation sites and fragmentation pathways. High activity of DCQ and its derivatives against Ae. aegypti larvae was demonstrated. CONCLUSION: Our results provided a well-founded characterization of the fragmentation reactions of DCQ and its derivatives, which can be useful for complementary studies of the development of a larvicidal product against Ae. aegypti.


Assuntos
Aedes , Espectrometria de Massas por Ionização por Electrospray , Animais , Espectrometria de Massas por Ionização por Electrospray/métodos , Espectrometria de Massas em Tandem/métodos , Larva
5.
Avian Pathol ; : 1-11, 2024 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-38662518

RESUMO

RESEARCH HIGHLIGHTS: RSS causes dysbiosis of the gut microbiota of the ilea of chicks.A difference was found in gut microbiota between chicks with or without RSS.Candidatus Arthromitus was predominant in chicks with RSS.Clostridium sensu stricto 1 was strictly associated with chicks with RSS.

6.
Epilepsy Behav ; 155: 109800, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38657485

RESUMO

Epilepsy is a neurological disease characterized by spontaneous and recurrent seizures. Epileptic seizures can be initiated and facilitated by inflammatory mechanisms. As the dysregulation of the immune system would be involved in epileptogenesis, it is suggested that anti-inflammatory medications could impact epileptic seizures. These medications could potentially have a side effect by altering the structure and composition of the intestinal microbiota. These changes can disrupt microbial homeostasis, leading to dysbiosis and potentially exacerbating intestinal inflammation. We hypothesize that prednisolone may affect the development of epileptic seizures, potentially influencing the diversity of the intestinal microbiota and the regulation of pro-inflammatory cytokines in intestinal tissue. This study aimed to evaluate the effects of prednisolone treatment on epileptic seizures and investigate the effect of this drug on the bacterial diversity of the intestinal microbiota and markers of inflammatory processes in intestinal tissue. We used Male Wistar rat littermates (n = 31, 90-day-old) divided into four groups: positive control treated with 2 mg/kg of diazepam (n = 6), negative control treated with 0.9 g% sodium chloride (n = 6), and the remaining two groups were subjected to treatment with prednisolone, with one receiving 1 mg/kg (n = 9) and the other 5 mg/kg (n = 10). All administrations were performed intraperitoneally (i.p.) over 14 days. To induce the chronic model of epileptic seizures, we administered pentylenetetrazole (PTZ) 25 mg/kg i.p. on alternate days. Seizure latency (n = 6 - 10) and TNF-α and IL-1ß concentrations from intestinal samples were measured by ELISA (n = 6 per group), and intestinal microbiota was evaluated with intergenic ribosomal RNA (rRNA) spacer (RISA) analysis (n = 6 per group). The prednisolone treatment demonstrated an increase in the latency time of epileptic seizures and TNF-α and IL-1ß concentrations compared to controls. There was no statistically significant difference in intestinal microbiota diversity between the different treatments. However, there was a strong positive correlation between microbial diversity and TNF-α and IL-1ß concentrations. The administration of prednisolone yields comparable results to diazepam on increasing latency between seizures, exhibiting promise for its use in clinical studies. Although there were no changes in intestinal microbial diversity, the increase in the TNF-α and IL-1ß cytokines in intestinal tissue may be linked to immune system signaling pathways involving the intestinal microbiota. Additional research is necessary to unravel the intricacies of these pathways and to understand their implications for clinical practice.


Assuntos
Citocinas , Modelos Animais de Doenças , Epilepsia , Microbioma Gastrointestinal , Excitação Neurológica , Prednisolona , Ratos Wistar , Animais , Prednisolona/farmacologia , Prednisolona/uso terapêutico , Masculino , Citocinas/metabolismo , Microbioma Gastrointestinal/efeitos dos fármacos , Excitação Neurológica/efeitos dos fármacos , Ratos , Epilepsia/tratamento farmacológico , Epilepsia/microbiologia , Anti-Inflamatórios/farmacologia
7.
Langenbecks Arch Surg ; 409(1): 202, 2024 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-38958771

RESUMO

PURPOSE: We aim to evaluate the impact of surgical wound complications in the first 30 postoperative days after incisional hernia repair on the long-term quality of life of patients. In addition, the impact of the surgical technique and preoperative comorbidities on the quality of life of patients will also be evaluated. METHOD: Prospective cohort study, which evaluates 115 patients who underwent incisional hernioplasty between 2019 and 2020, using the onlay and retromuscular techniques. These patients were initially assessed with regard to surgical wound outcomes in the first 30 postoperative days (surgical site infection (SSI) or surgical site occurrence (SSO)), and then, assessed after three years, through a specific quality of life questionnaire, the Hernia Related Quality of Life Survey (HerQLes). RESULTS: After some patients were lost to follow-up during the study period, due to death, difficulty in contact, refusal to respond to the questionnaire, eighty patients were evaluated. Of these, 11 patients (13.8%) had SSI in the first 30 postoperative days and 37 (46.3%) had some type of SSO. The impact of both SSI and SSO on quality of life indices was not identified. When analyzing others variables, we observed that the Body Mass Index (BMI) had a significant impact on the patients' quality of life. Likewise, hernia size and mesh size were identified as variables related to a worse quality of life outcome. No difference was observed regarding the surgical techniques used. CONCLUSION: In the present study, no relationship was identified between surgical wound outcomes (SSO and SSI) and worse quality of life results using the HerQLes score. We observed that both BMI and the size of meshes and hernias showed an inversely proportional relationship with quality of life indices. However, more studies evaluating preoperative quality of life indices and comparing them with postoperative indices should be carried out to evaluate these correlations.


Assuntos
Herniorrafia , Hérnia Incisional , Qualidade de Vida , Infecção da Ferida Cirúrgica , Cicatrização , Humanos , Feminino , Masculino , Hérnia Incisional/cirurgia , Herniorrafia/efeitos adversos , Herniorrafia/métodos , Estudos Prospectivos , Pessoa de Meia-Idade , Idoso , Cicatrização/fisiologia , Inquéritos e Questionários , Adulto , Telas Cirúrgicas , Estudos de Coortes
8.
Lasers Med Sci ; 39(1): 110, 2024 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-38649644

RESUMO

The sample comprised 44 volunteers who had undergone some surgical procedure and were equally divided into four groups. G1 started the therapy 24 h after the surgical procedure with the device off. G2 followed the same time pattern, 24 h, but with the device turned on. G3 and G4 started therapy three days after the surgical procedure; in G3, the device was turned off, and in G4, the device remained on during therapy; each session lasted 30 min, using 660 nm (red), energy 180 J. For all groups, the therapy started with daily use for seven days and followed the interval use of three times a week until completed 21 days. The revaluation was performed after 7 and 21 days. The results found show changes in HR at rest, systolic and diastolic BP, and in peripheral oxygen saturation, which showed a significant difference in the groups that used on-therapy (p < 0.05). In the MCGILL Scale evaluation, the mean total score showed a more accentuated drop in the groups that used ILIB, (p < 0.05). ILIB may have prevented a more significant evolution of firosis levels; however, no changes were observed in the evaluation of sleep and anxiety. The application of the ILIB in patients undergoing plastic surgery was supported in terms of hemodynamics and pain; in addition, starting the ILIB application 24 h after the procedure proved to be more advantageous.


Assuntos
Procedimentos de Cirurgia Plástica , Humanos , Feminino , Masculino , Adulto , Pessoa de Meia-Idade , Procedimentos de Cirurgia Plástica/métodos , Técnica de Ilizarov/instrumentação , Hemodinâmica , Adulto Jovem , Saturação de Oxigênio , Cirurgia Plástica/métodos
9.
Int J Sports Med ; 45(8): 624-632, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38684188

RESUMO

We analyzed the effects of load magnitude and bar velocity variables on sensitivity to fatigue. Seventeen resistance-trained men (age=25.7±4.9 years; height=177.0±7.2 cm; body mass=77.7±12.3 kg; back-squat 1RM=145.0±33.9 kg; 1RM/body mass=1.86) participated in the study. Pre- and post-exercise changes in the mean propulsive velocity (MPV) and peak velocity (PV) in the back-squat at different intensities were compared with variations in the countermovement jump (CMJ). CMJ height decreased significantly from pre- to post-exercise (∆%=-7.5 to -10.4; p<0.01; ES=0.37 to 0.60). Bar velocity (MPV and PV) decreased across all loads (∆%=-4.0 to -12.5; p<0.01; ES=0.32 to 0.66). The decrease in performance was similar between the CMJ, MPV (40% and 80% 1RM; p=1.00), and PV (80% 1RM; p=1.00). The magnitude of reduction in CMJ performance was greater than MPV (60% 1RM; p=0.05) and PV (40% and 60% 1RM; p<0.01) at the post-exercise moment. Low systematic bias and acceptable levels of agreement were only found between CMJ and MPV at 40% and 80% 1RM (bias=0.35 to 1.59; ICC=0.51 to 0.71; CV=5.1% to 8.5%). These findings suggest that the back-squat at 40% or 80% 1RM using MPV provides optimal sensitivity to monitor fatigue through changes in bar velocity.


Assuntos
Fadiga Muscular , Treinamento Resistido , Humanos , Masculino , Treinamento Resistido/métodos , Fadiga Muscular/fisiologia , Adulto , Adulto Jovem , Exercício Pliométrico
10.
J Prosthodont ; 33(2): 180-187, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36799260

RESUMO

PURPOSE: To evaluate the tendency of movement, stress distribution, and microstrain of single-unit crowns in simulated cortical and trabecular bone, implants, and prosthetic components of narrow-diameter implants with different lengths placed at the crestal and subcrestal levels in the maxillary anterior region using 3D finite element analysis (FEA). MATERIALS AND METHODS: Six 3D models were simulated using Invesalius 3.0, Rhinoceros 4.0, and SolidWorks software. Each model simulated the right anterior maxillary region including a Morse taper implant of Ø2.9 mm with different lengths (7, 10, and 13 mm) placed at the crestal and subcrestal level and supporting a cement-retained monolithic single crown in the area of tooth 12. The FEA was performed using ANSYS 19.2. The simulated applied force was 178 N at 0°, 30°, and 60°. The results were analyzed using maps of displacement, von Mises (vM) stress, maximum principal stress, and microstrain. RESULTS: Models with implants at the subcrestal level showed greater displacement. vM stress increased in the implant and prosthetic components when implants were placed at the subcrestal level compared with the crestal level; the length of the implants had a low influence on the stress distribution. Higher stress and strain concentrations were observed in the cortical bone of the subcrestal placement, independent of implant length. Non-axial loading influenced the increased stress and strain in all the evaluated structures. CONCLUSIONS: Narrow-diameter implants positioned at the crestal level showed a more favorable biomechanical behavior for simulated cortical bone, implants, and prosthetic components. Implant length had a smaller influence on stress or strain distribution than the other variables.


Assuntos
Implantes Dentários , Análise de Elementos Finitos , Análise do Estresse Dentário/métodos , Planejamento de Prótese Dentária , Software , Estresse Mecânico , Fenômenos Biomecânicos
11.
Nurs Crit Care ; 29(2): 274-286, 2024 03.
Artigo em Inglês | MEDLINE | ID: mdl-37882508

RESUMO

BACKGROUND: Labelling is a strategy that contributes to the correct and faster identification of drugs, minimizing misidentification. There is a gap in knowledge on optimal labelling standards for intravenous (IV) devices applied to the care of critically ill patients. AIM: The goal of this article was to map existing knowledge on the labelling of IV drug delivery devices in critically ill patients for the prevention of medication errors. STUDY DESIGN: This was a scoping review conducted according to the JBI methodology in the LILACS, MEDLINE, CINAHL, IBECS, Scopus, Embase and Web of Science databases, and on the websites of specialized institutions. Searches were conducted up to December 2022 for scientific articles and grey literature that addressed the labelling of IV devices in intensive care units, emergency departments, and anaesthesia units. The data were collected using a structured form and were later classified, summarized, and aggregated to map the knowledge related to the review question. RESULTS: Twenty-one documents were included, which demonstrated variability in label use with IV drug delivery devices. The following features of structure and design stood out: printed format, colour coding, letter size differentiation, and the use of sturdy material. In terms of information, the name of the drug, dose, date and time of preparation, identification of the patient, and who prepared it were found. CONCLUSIONS: The identified patterns contributed to the reduction of drug misidentification and the development of timelier drug labelling and administration. RELEVANCE TO CLINICAL PRACTICE: The evidence supports the development of standardized labels for the prevention of medication errors.


Assuntos
Estado Terminal , Unidades de Terapia Intensiva , Humanos
12.
Glob Chang Biol ; 29(21): 6077-6092, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37698497

RESUMO

Understanding the effects of intensification of Amazon basin hydrological cycling-manifest as increasingly frequent floods and droughts-on water and energy cycles of tropical forests is essential to meeting the challenge of predicting ecosystem responses to climate change, including forest "tipping points". Here, we investigated the impacts of hydrological extremes on forest function using 12+ years of observations (between 2001-2020) of water and energy fluxes from eddy covariance, along with associated ecological dynamics from biometry, at the Tapajós National Forest. Measurements encompass the strong 2015-2016 El Niño drought and La Niña 2008-2009 wet events. We found that the forest responded strongly to El Niño-Southern Oscillation (ENSO): Drought reduced water availability for evapotranspiration (ET) leading to large increases in sensible heat fluxes (H). Partitioning ET by an approach that assumes transpiration (T) is proportional to photosynthesis, we found that water stress-induced reductions in canopy conductance (Gs ) drove T declines partly compensated by higher evaporation (E). By contrast, the abnormally wet La Niña period gave higher T and lower E, with little change in seasonal ET. Both El Niño-Southern Oscillation (ENSO) events resulted in changes in forest structure, manifested as lower wet-season leaf area index. However, only during El Niño 2015-2016, we observed a breakdown in the strong meteorological control of transpiration fluxes (via energy availability and atmospheric demand) because of slowing vegetation functions (via shutdown of Gs and significant leaf shedding). Drought-reduced T and Gs , higher H and E, amplified by feedbacks with higher temperatures and vapor pressure deficits, signaled that forest function had crossed a threshold, from which it recovered slowly, with delay, post-drought. Identifying such tipping point onsets (beyond which future irreversible processes may occur) at local scale is crucial for predicting basin-scale threshold-crossing changes in forest energy and water cycling, leading to slow-down in forest function, potentially resulting in Amazon forests shifting into alternate degraded states.

13.
World J Urol ; 41(3): 709-724, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36867239

RESUMO

PURPOSE: Radiomics in uro-oncology is a rapidly evolving science proving to be a novel approach for optimizing the analysis of massive data from medical images to provide auxiliary guidance in clinical issues. This scoping review aimed to identify key aspects wherein radiomics can potentially improve the accuracy of diagnosis, staging, and extraprostatic extension in prostate cancer (PCa). METHODS: The literature search was performed on June 2022 using PubMed, Embase, and Cochrane Central Controlled Register of Trials. Studies were included if radiomics were compared with radiological reports only. RESULTS: Seventeen papers were included. The combination of PIRADS and radiomics score models improves the PIRADS score reporting of 2 and 3 lesions even in the peripheral zone. Multiparametric MRI-based radiomics models suggest that by simply omitting diffusion contrast enhancement imaging in radiomics models can simplify the process of analysis of clinically significant PCa by PIRADS. Radiomics features correlated with the Gleason grade with excellent discriminative ability. Radiomics has higher accuracy in predicting not only the presence but also the side of extraprostatic extension. CONCLUSIONS: Radiomics research on PCa mainly uses MRI as an imaging modality and is focused on diagnosis and risk stratification and has the best future possibility of improving PIRADS reporting. Radiomics has established its superiority over radiologist-reported outcomes but the variability has to be taken into consideration before translating it to clinical practice.


Assuntos
Imageamento por Ressonância Magnética Multiparamétrica , Neoplasias da Próstata , Masculino , Humanos , Neoplasias da Próstata/diagnóstico por imagem , Neoplasias da Próstata/patologia , Imageamento por Ressonância Magnética/métodos , Gradação de Tumores , Radiologistas , Estudos Retrospectivos
14.
J Fluoresc ; 2023 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-37542587

RESUMO

In this study, we present the synthesis of benzimidazo[1,2-a] quinoline-based heterocycles bearing organosulfur and organoselenium moieties through transition-metal-free cascade reactions involving a sequential intermolecular aromatic nucleophilic substitution (SNAr). Both sulfur and selenium derivatives presented absorption maxima located around 355 nm related to spin and symmetry allowing electronic 1π-π* transitions, and fluorescence emission at the violet-blue region (~440 nm) with relatively large Stokes shift. The fluorescence quantum yields were slightly influenced by the chalcogen, with the sulfur derivatives presenting higher values than the selenium analogs. In this sense, the quantum yields for selenium derivatives can probably be affected by the intersystem crossing or even the photoinduced electron transfer process (PET). The compounds were successfully applied in all-solution-processed organic light-emitting diodes (OLEDs), where poly(9-vinylcarbazole) was employed as a dispersive matrix generating single-layer device cells. The obtained electroluminescence spectra are a sum of benzimidazo[1,2-a]quinolines and PVK singlet and/or triplet emissive states, according to their respective energy band gaps. The best diode rendered a luminance of 25.4 cd⋅m-2 with CIE (0.17, 0.14) and current efficiency of 20.2 mcd⋅A-1, a fivefold improvement in comparison to the PVK device that was explained by a 50-fold increase of charge-carriers electrical mobility.

15.
Appl Opt ; 62(8): C30-C37, 2023 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-37133054

RESUMO

In recent years, an unconventional excitation of trivalent neodymium ions (N d 3+) at 1064 nm, not resonant with ground-state transitions, has been investigated with the unprecedented demonstration of a photon-avalanche-like (PA-like) mechanism, in which the temperature increase plays a fundamental role. As a proof-of-concept, N d A l 3(B O 3)4 particles were used. A consequence of the PA-like mechanism is the absorption enhancement of excitation photons providing light emission at a broad range covering the visible and near-infrared spectra. In the first study, the temperature increase was due to intrinsic nonradiative relaxations from the N d 3+ and the PA-like mechanism ensued at a given excitation power threshold (P t h ). Subsequently, an external heating source was used to trigger the PA-like mechanism while keeping the excitation power below P t h at room temperature. Here, we demonstrate the switching on of the PA-like mechanism by an auxiliary beam at 808 nm, which is in resonance with the N d 3+ ground-state transition 4 I 9/2→{4 F 5/2,2 H 9/2}. It comprises the first, to the best of our knowledge, demonstration of an optical switched PA, and the underlying physical mechanism is the additional heating of the particles due to the phonon emissions from the N d 3+ relaxation pathways when exciting at 808 nm. The present results have potential applications in controlled heating and remote temperature sensing.

16.
Planta Med ; 89(7): 700-708, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36889328

RESUMO

Licarin A, a dihydrobenzofuranic neolignan presents in several medicinal plants and seeds of nutmeg, exhibits strong activity against protozoans responsible for Chagas disease and leishmaniasis. From biomimetic reactions by metalloporphyrin and Jacobsen catalysts, seven products were determined: four isomeric products yielded by epoxidation from licarin A, besides a new product yielded by a vicinal diol, a benzylic aldehyde, and an unsaturated aldehyde in the structure of the licarin A. The incubation with rat and human liver microsomes partially reproduced the biomimetic reactions by the production of the same epoxidized product of m/z 343 [M + H]+. In vivo acute toxicity assays of licarin A suggested liver toxicity based on biomarker enzymatic changes. However, microscopic analysis of tissues sections did not show any tissue damage as indicative of toxicity after 14 days of exposure. New metabolic pathways of the licarin A were identified after in vitro biomimetic oxidation reaction and in vitro metabolism by rat or human liver microsomes.


Assuntos
Lignanas , Metaloporfirinas , Ratos , Humanos , Animais , Biomimética , Oxirredução , Lignanas/toxicidade , Metaloporfirinas/metabolismo , Microssomos Hepáticos/metabolismo
17.
Oral Dis ; 2023 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-37994179

RESUMO

BACKGROUND: Here, we evaluated whether the histone lysine demethylase 5B (JARID1B), is involved in osteogenic phenotype commitment of periodontal ligament cells (PDLCs), by considering their heterogeneity for osteoblast differentiation. MATERIALS AND METHODS: Epigenetic, transcriptional, and protein levels of a gene set, involved in the osteogenesis, were investigated by performing genome-wide DNA (hydroxy)methylation, mRNA expression, and western blotting analysis at basal (without osteogenic induction), and at the 3rd and 10th days of osteogenic stimulus, in vitro, using PDLCs with low (l) and high (h) osteogenic potential as biological models. RESULTS: h-PDLCs showed reduced levels of JARID1B, compared to l-PDLCs, with significant inversely proportional correlations between RUNX2 and RUNX2/p57. Epigenetically, a significant reduction in the global H3K4me3 content was observed only in h-PDLCs. Immunoblotting data reveal a significant reduction in the global H3K4me3 content, at 3 days of induction only in h-PDLCs, while an increase in the global H3K4me3 content was observed at 10 days for both PDLCs. Additionally, positive correlations were found between global H3K4me3 levels and JARID1B gene expression. CONCLUSIONS: Altogether, our results show the crucial role of JARID1B in repressing PDLCs osteogenic phenotype and this claims to pre-clinical protocols proposing JARID1B as a potential therapeutic target.

18.
J Cosmet Laser Ther ; 25(5-8): 95-101, 2023 Nov 17.
Artigo em Inglês | MEDLINE | ID: mdl-38032251

RESUMO

This study evaluated the effects of laser application of diverse wavelengths applied simultaneously and on different skins. The sample included two participants, a woman with light skin with abdominal hair and a woman with dark skin and hair on the inner part of the lower limbs, who received a laser therapy session. After 45 days from laser application, abdominoplasty and thigh dermolipectomy surgery were performed. In the control sample, the hair follicles were in the anagen phase, showing the presence of Bcl-2 expression. In the treated areas, follicles were observed in an advanced phase (telogen), with the presence of CK-18 and negativity of Bcl-2, highlighting the phase of hair loss at that moment and the complete apoptosis of the investigated follicle. Significant difference was observed in the comparison of the anagen phase (p = .00) and it similarly occurred in the comparison of the telogen phase (p = .00). The presence of a greater amount of follicles in the anagen phase in the control area and follicles in the telogen phase in the treated area demonstrates the efficiency of the laser at different wavelengths when reaching different skin phototypes and hair thickness, being reinforced by apoptosis and cell proliferation markers. Therefore, the hair-removal process has been optimized with various laser wavelengths.


Assuntos
Remoção de Cabelo , Feminino , Humanos , Cabelo , Pele , Folículo Piloso , Lasers , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo
19.
Mikrochim Acta ; 190(8): 312, 2023 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-37470849

RESUMO

The development of miniaturized, sustainable and eco-friendly analytical sensors with low production cost is a current trend worldwide. Within this idea, this work presents  the innovative use of masked stereolithography (MSLA) 3D-printed substrates for the easy fabrication of pencil-drawn electrochemical sensors (MSLA-3D-PDE). The use of a non-toxic material such as pencil (electrodes) together with a biodegradable 3D printing resin (substrate) allowed the production of devices that are quite cheap (ca. US$ 0.11 per sensor) and with low environmental impact. Compared to paper, which is the most used substrate for manufacturing pencil-drawn electrodes, the MSLA-3D-printed substrate has the advantages of not absorbing water (hydrophobicity) or becoming crinkled and weakened when in contact with solutions. These features provide more reproducible, reliable, stable, and long-lasting sensors. The MSLA-3D-PDE, in conjunction with the custom cell developed, showed excellent robustness and electrochemical performance similar to that observed of the glassy carbon electrode, without the need of any activation procedure. The analytical applicability of this platform was explored through the quantification of omeprazole in pharmaceuticals. A limit of detection (LOD) of 0.72 µmol L-1 was achieved, with a linear range of 10 to 200 µmol L-1. Analysis of real samples provided results that were highly concordant with those obtained by UV-Vis spectrophotometry (relative error ≤ 1.50%). In addition, the greenness of this approach was evaluated and confirmed by a quantitative methodology (Eco-Scale index). Thus, the MSLA-3D-PDE appears as a new and sustainable tool with great potential of use in analytical electrochemistry.

20.
Mikrochim Acta ; 190(12): 461, 2023 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-37926729

RESUMO

Microfluidic cotton thread-based electroanalytical devices (µTEDs) are analytical systems with attractive features such as spontaneous passive flow, low cost, minimal waste production, and good sensitivity. Currently, sample injection in µTEDs is performed by hand using manual micropipettes, which have drawbacks such as inconstant speed and position, dependence of skilled analysts, and need of physical effort of operator during prolonged times, leading to poor reproducibility and risk of strain injury. As an alternative to these inconveniences, we propose, for the first time, the use of electronic micropipettes to carry out automated injections in µTEDs. This new approach avoids all disadvantages of manual injections, while also improving the performance, experience, and versatility of µTEDs. The platform developed here is composed by three 3D-printed electrodes (detector) attached to a 3D-printed platform containing an adjustable holder that keeps the electronic pipette in the same x/y/z position. As a proof-of-concept, both injection modes (manual and electronic) were compared using three model analytes (nitrite, paracetamol, and 5-hydroxytryptophan) on µTED with amperometric detection. As result, improved analytical performance (limits of detection between 2.5- and 5-fold lower) was obtained when using electronic injections, as well as better repeatability/reproducibility and higher analytical frequencies. In addition, the determination of paracetamol in urine samples suggested better precision and accuracy for automated injection. Thus, electronic injection is a great advance and changes the state-of-art of µTEDs, mainly considering the use of more modern and versatile electronic pipettes (wider range of pre-programmed modes), which can lead to the development of even more automated systems.

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