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1.
Opt Express ; 32(6): 10033-10045, 2024 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-38571224

RESUMO

Fiber optic interferometry combined with recognizing elements has attracted intensive attention for the development of different biosensors due to its superior characteristic features. However, the immobilization of sensing elements alone is not capable of low-concentration detection due to weak interaction with the evanescent field of the sensing transducer. The utilization of different 2D materials with high absorption potential and specific surface area can enhance the intensity of the evanescent field and hence the sensitivity of the sensor. Here, a biosensor has been fabricated using an inline hetero fiber structure of photonic crystal fiber (PCF) and single-mode fiber (SMF) functionalized with a nanocomposite of molybodenum di-sulfide (MoS2) and molecular imprinting polymer (MIP) to detect trace levels of bovine serum albumin (BSA). The sensor showed a wide dynamic detection range with a high sensitivity of 2.34 × 107 pm/µg L-1. It shows working potential over a wide pH range with a subfemtomolar detection limit. The compact size, easy fabrication, stable structure, long detection range, and high sensitivity of this sensor would open a new path for the development of different biosensors for online and remote sensing applications.


Assuntos
Impressão Molecular , Nanocompostos , Polímeros/química , Molibdênio , Tecnologia de Fibra Óptica
2.
Opt Express ; 32(6): 10077-10092, 2024 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-38571228

RESUMO

Every year, millions of people suffer some form of illness associated with the consumption of contaminated food. Escherichia coli (E. coli), found in the intestines of humans and other animals, is commonly associated with various diseases, due to the existence of pathogenic strains. Strict monitoring of food products for human consumption is essential to ensure public health, but traditional cell culture-based methods are associated with long waiting times and high costs. New approaches must be developed to achieve cheap, fast, and on-site monitoring. Thus, in this work, we developed optical fiber sensors based on surface plasmon resonance. Gold and cysteamine-coated fibers were functionalized with anti-E. coli antibody and tested using E. coli suspensions with concentrations ranging from 1 cell/mL to 105 cells/mL. An average logarithmic sensitivity of 0.21 ± 0.01 nm/log(cells/mL) was obtained for three independent assays. An additional assay revealed that including molybdenum disulfide resulted in an increase of approximately 50% in sensitivity. Specificity and selectivity were also evaluated, and the sensors were used to analyze contaminated water samples, which verified their promising applicability in the aquaculture field.


Assuntos
Técnicas Biossensoriais , Ressonância de Plasmônio de Superfície , Animais , Humanos , Ressonância de Plasmônio de Superfície/métodos , Escherichia coli , Fibras Ópticas , Técnicas Biossensoriais/métodos , Imunoensaio
3.
Opt Express ; 32(6): 9610-9624, 2024 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-38571191

RESUMO

High-scattering optical fibers have emerged as a key component in distributed sensing systems, primarily due to their capacity to enhance signal-to-noise ratio. This paper presents an experimental characterization of optical fibers doped with oxide nanoparticles for displacement sensing. They were manufactured using the phase-separation technique and different doping compounds, including calcium, strontium, lanthanum and magnesium. The Rayleigh backscattering (RBS) signatures in time and frequency domains were acquired using an Optical Backscatter Reflectometer (OBR). The maximum representative length, backscattering gain and strain sensitivity were evaluated. The results indicate that the fiber co-doped with magnesium and erbium chlorides offered the best compromise between strain sensitivity (0.96 pm/µ ϵ) and maximum length (17 m). For conditions of single and multiple perturbations, strain saturation was reached at ≥7000 µm and <1500 µm, respectively. In addition, the results reveal that, under a condition of variable temperature (30-60 °C), the sensor response becomes significantly nonlinear over length, requiring a technique for temperature cross-sensitivity mitigation that accounts for nonlinearities in sensitivity and hysteresis.

4.
Arq Bras Cir Dig ; 36: e1785, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38511799

RESUMO

BACKGROUND: There is a lack of valid and specific tools to measure chronic constipation severity in Brazil. AIMS: To validate the Constipation Scoring System for Brazilian spoken Portuguese. METHODS: Translation, cultural adaptation, and validation itself (reliability and convergent and divergent validation). Translation: definitive version from the original version's translation and evaluation by specialists. Cultural adaptation: score content analysis of the definitive version, as an interview to patients. Interobserver reliability: application by two researchers on the same day. Intraobserver reliability: same researcher at different times, in a 7-day interval. Divergent validation: non-constipated volunteers. Convergent validation: two groups, good response to clinical treatment and refractory to treatment. RESULTS: Cultural adaptation: 81 patients, 89% female, with mean age of 55 and seven years of schooling, and overall content validity index was 96.5%. Inter and intraobserver reliability analysis: 60 patients, 86.7% female, mean age of 56 and six years of schooling, and the respective intraclass correlation coefficients were 0.991 and 0.987, p<0.001. Divergent validation: 40 volunteers, 25 male, mean age of 49 years, and the mean global score was 2. Convergent validation of patients with good response to clinical treatment: 47 patients, 39 female, mean age of 60 and six years of schooling, and the pre- and post-treatment scores were 19 and 8, respectively (p<0.001). Convergent validation of refractory to clinical treatment patients: 75 patients, 70 female, mean age of 53 and seven years of schooling, and the global average score was 22. CONCLUSIONS: The Constipation Scoring System (Índice de Gravidade da Constipação Intestinal) validated for the Brazilian population is a reliable instrument for measuring the severity of intestinal chronic constipation.


Assuntos
Constipação Intestinal , Idioma , Humanos , Masculino , Feminino , Pessoa de Meia-Idade , Inquéritos e Questionários , Reprodutibilidade dos Testes , Portugal , Constipação Intestinal/diagnóstico , Brasil
5.
Toxics ; 12(3)2024 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-38535944

RESUMO

The saltmarsh plant Halimione portulacoides was shortly exposed to realistic levels of inorganic mercury (iHg) with the aim of investigating the adaptative processes of the roots and leaves regarding redox homeostasis, physiology, and Hg accumulation. Plants were collected at a contaminated (CONT) and a reference (REF) site to address the interference of contamination backgrounds. The influence of major abiotic variables (i.e., temperature and light) was also examined. Total Hg levels, antioxidant enzymes, lipid peroxidation (LPO), and photosynthetic activity were analyzed after 2 and 4 h of exposure. A poor accumulation of Hg in the roots was noticed, and no translocation to the stems and leaves was found, but plants from the CONT site seemed more prone to iHg uptake (in winter). Despite this, antioxidant modulation in the roots and leaves was found, disclosing, in winter, higher thresholds for the induction of enzymatic antioxidants in CONT leaves compared to REF plants, denoting that the former are better prepared to cope with iHg redox pressure. Consistently, CONT leaves exposed to iHg had remarkably lower LPO levels. Exposure did not impair photosynthetic activity, pinpointing H. portulacoides' ability to cope with iHg toxicity under very-short-term exposure. Biochemical changes were noticed before enhancements in accumulation, reinforcing the relevance of these responses in precociously signaling iHg toxicity.

6.
Biophys J ; 123(7): 901-908, 2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38449310

RESUMO

A cell-penetrating peptide (CPP) is a short amino-acid sequence capable of efficiently translocating across the cellular membrane of mammalian cells. However, the potential of CPPs as a delivery vector is hampered by the strong reduction of its translocation efficiency when it bears an attached molecular cargo. To overcome this problem, we used previously developed diblock copolymers of elastin-like polypeptides (ELPBCs), which we end functionalized with TAT (transactivator of transcription), an archetypal CPP built from a positively charged amino acid sequence of the HIV-1 virus. These ELPBCs self-assemble into micelles at a specific temperature and present the TAT peptide on their corona. These micelles can recover the lost membrane affinity of TAT and can trigger interactions with the membrane despite the presence of a molecular cargo. Herein, we study the influence of membrane surface charge on the adsorption of TAT-functionalized ELP micelles onto giant unilamellar vesicles (GUVs). We show that the TAT-ELPBC micelles show an increased binding constant toward negatively charged membranes compared to neutral membranes, but no translocation is observed. The affinity of the TAT-ELPBC micelles for the GUVs displays a stepwise dependence on the lipid charge of the GUV, which, to our knowledge, has not been reported previously for interactions between peptides and lipid membranes. By unveiling the key steps controlling the interaction of an archetypal CPP with lipid membranes, through regulation of the charge of the lipid bilayer, our results pave the way for a better design of delivery vectors based on CPPs.


Assuntos
Peptídeos Penetradores de Células , Micelas , Animais , Polipeptídeos Semelhantes à Elastina , Adsorção , Bicamadas Lipídicas/química , Peptídeos/química , Lipossomas Unilamelares/química , Peptídeos Penetradores de Células/química , Mamíferos/metabolismo
7.
Crit Rev Oncog ; 29(2): 53-63, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38505881

RESUMO

The protocol for treating locally advanced rectal cancer consists of the application of chemoradiotherapy (neoCRT) followed by surgical intervention. One issue for clinical oncologists is predicting the efficacy of neoCRT in order to adjust the dosage and avoid treatment toxicity in cases when surgery should be conducted promptly. Biomarkers may be used for this purpose along with in vivo cell-level images of the colorectal mucosa obtained by probe-based confocal laser endomicroscopy (pCLE) during colonoscopy. The aim of this article is to report our experience with Motiro, a computational framework that we developed for machine learning (ML) based analysis of pCLE videos for predicting neoCRT response in locally advanced rectal cancer patients. pCLE videos were collected from 47 patients who were diagnosed with locally advanced rectal cancer (T3/T4, or N+). The patients received neoCRT. Response to treatment by all patients was assessed by endoscopy along with biopsy and magnetic resonance imaging (MRI). Thirty-seven patients were classified as non-responsive to neoCRT because they presented a visible macroscopic neoplastic lesion, as confirmed by pCLE examination. Ten remaining patients were considered responsive to neoCRT because they presented lesions as a scar or small ulcer with negative biopsy, at post-treatment follow-up. Motiro was used for batch mode analysis of pCLE videos. It automatically characterized the tumoral region and its surroundings. That enabled classifying a patient as responsive or non-responsive to neoCRT based on pre-neoCRT pCLE videos. Motiro classified patients as responsive or non-responsive to neoCRT with an accuracy of ~ 0.62 when using images of the tumor. When using images of regions surrounding the tumor, it reached an accuracy of ~ 0.70. Feature analysis showed that spatial heterogeneity in fluorescence distribution within regions surrounding the tumor was the main contributor to predicting response to neoCRT. We developed a computational framework to predict response to neoCRT by locally advanced rectal cancer patients based on pCLE images acquired pre-neoCRT. We demonstrate that the analysis of the mucosa of the region surrounding the tumor provides stronger predictive power.


Assuntos
Neoplasias Colorretais , Segunda Neoplasia Primária , Neoplasias Retais , Humanos , Terapia Neoadjuvante , Microscopia Confocal/métodos , Colonoscopia/métodos , Neoplasias Colorretais/diagnóstico , Neoplasias Retais/diagnóstico por imagem , Neoplasias Retais/terapia
8.
Arq Bras Cir Dig ; 36: e1792, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38324853

RESUMO

BACKGROUND: The laparoscopic approach considerably reduced the morbidity of colorectal surgery when compared to the open approach. Among its benefits, we can highlight less intraoperative bleeding, early oral intake, lower rates of surgical site infection, incisional hernia, and postoperative pain, and earlier hospital discharge. AIMS: To compare the perioperative morbidity of right versus left colectomy for cancer and the quality of laparoscopic oncologic resection. METHODS: Retrospective analysis of patients submitted to laparoscopic right and left colctomy between 2006 and 2016. Postoperative complications were classified using the Clavien-Dindo scale, 30 days after surgery. RESULTS: A total of 293 patients were analyzed, 97 right colectomies (33.1%) and 196 left colectomies (66.9%). The averageage was 62.8 years. The groups were comparable in terms of age, comorbidities, body mass index, and the American Society of Anesthesiology (ASA) classification. Preoperative transfusion was higher in the right colectomy group (5.1% versus 0.4%, p=0.004, p<0.05). Overall, 233 patients (79.5%) had no complications. Complications found were grade I and II in 62 patients (21.1%) and grade III to V in 37 (12.6%). Twenty-three patients (7.8%) underwent reoperation. The comparison between left and right colectomy was not statistically different for operative time, conversion, reoperation, severe postoperative complications, and length of stay. The anastomotic leak rate was comparable in both groups(5.6% versus 2.1%, p=0.232, p>0.05). The oncological results were similar in both surgeries. In multiple logistic regression, ASA statistically influenced the worst results (≥ III; p=0.029, p<0.05). CONCLUSIONS: The surgical and oncological results of laparoscopic right and left colectomies are similar, making this the preferred approach for both procedures.


Assuntos
Laparoscopia , Neoplasias , Humanos , Estudos Retrospectivos , Infecção da Ferida Cirúrgica , Neoplasias/complicações , Laparoscopia/métodos , Colectomia/métodos , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/etiologia , Resultado do Tratamento , Tempo de Internação
9.
Rev Sci Instrum ; 95(2)2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-38341721

RESUMO

Aquaculture presents itself as one of the most rapidly developing means of sustainable production of animal protein to feed ever-growing populations. Recirculating aquaculture systems offer higher control and fewer inconveniences than traditional systems, making them an attractive option for fish production. Although the sector's digitalization is in its early stages, its application should increase its rentability while conserving the environment. This paper aims to promote the sector's evolution by assessing parameter importance in mortality with tree-based machine learning models, verifying the method's natural robustness and how it compares to a specially devised one, and at the same time evaluating the concept's relevance in predicting categorical mortality values. In particular, to better understand the aquaculture production process through a systematic data evaluation, an exploration based on real-time data acquisition is fully needed. Moreover, algorithm robustness is a key ingredient in this application since measurements are greatly affected by errors. This invalidates the application of traditional machine learning methods, where models are sensitive to production data variations and sensor noise. The study found the parameters that play relevant roles in the production phases, such as pH and nitrate concentration. While the obtained predictive metrics are still sub-optimal, further enhancements could be achieved through rigorous analysis of feature engineering, fine-tuning model hyperparameters, and exploring more advanced algorithms. Additionally, incorporating larger and more diverse datasets, refining data pre-processing techniques, and iteratively optimizing the model architecture may contribute to significant improvements in predictive performance. Despite that, the impact costs of using adjusted machine learning metrics are clear, as are the importance of data rounding in pre-processing and directions for improvement regarding data acquisition and transformation.


Assuntos
Algoritmos , Aquicultura , Animais , Aprendizado de Máquina , Nitratos
10.
Palliat Support Care ; : 1-9, 2024 Feb 29.
Artigo em Inglês | MEDLINE | ID: mdl-38420704

RESUMO

OBJECTIVES: Spirituality, emotional intelligence, and palliative care (PC) knowledge have a positive and direct influence on self-efficacy and on perception of preparation and ability to provide end-of-life (EOL) care. The aim of this work is to propose a conceptual model that relates spirituality, emotional intelligence, PC knowledge, self-efficacy, and the preparation and ability to provide EOL care by doctors and nurses. METHODS: Quantitative, exploratory, descriptive, and inferential study applied to doctors and nurses in a hospital in the north of Portugal, between May and July 2022. The data collection instrument includes a questionnaire. The relationships between latent variables were evaluated using structural equation models by the partial least squares method using the Smart PLS 3.0 software. It was obtained the previous authorization of the ethics committee. RESULTS: The results (n = 380) indicate that self-efficacy, spirituality, and PC knowledge have a positive influence on the ability to provide EOL care. Emotional intelligence and spirituality have a direct and positive effect on self-efficacy. There is no direct influence of emotional intelligence on the ability to provide EOL care, but emotional intelligence has an indirect effect mediated by self-efficacy. SIGNIFICANCE OF RESULTS: Spirituality, self-efficacy, and emotional intelligence are very important for the ability of doctors and nurses to provide EOL care. The identification of predictive factors of the ability to provide EOL care and the determination of the relationship between them can improve the provision of EOL care, reduction of health costs, timely and early referral of people to PC, and increase life quality.

11.
ACS Appl Mater Interfaces ; 16(7): 8333-8345, 2024 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-38321958

RESUMO

With the advantages of high flexibility, strong real-time monitoring capabilities, and convenience, wearable devices have shown increasingly powerful application potential in medical rehabilitation, health monitoring, the Internet of Things, and human-computer interaction. In this paper, we propose a novel and wearable optical microfiber intelligent sensor based on a wavy-shaped polymer optical microfiber (WPOMF) for cardiorespiratory and behavioral monitoring of humans. The optical fibers based on polymer materials are prepared into optical microfibers, fully using the advantages of the polymer material and optical microfibers. The prepared polymer optical microfiber is designed into a flexible wave-shaped structure, which enables the WPOMF sensor to have higher tensile properties and detection sensitivity. Cardiorespiratory and behavioral detection experiments based on the WPOMF sensor are successfully performed, which demonstrates the high sensitivity and stability potential of the WPOMF sensor when performing wearable tasks. Further, the success of the AI-assisted medical keyword pronunciation recognition experiment fully demonstrates the feasibility of integrating AI technology with the WPOMF sensor, which can effectively improve the intelligence of the sensor as a wearable device. As an optical microfiber intelligent sensor, the WPOMF sensor offers broad application prospects in disease monitoring, rehabilitation medicine, the Internet of Things, and other fields.


Assuntos
Polímeros , Dispositivos Eletrônicos Vestíveis , Humanos , Monitorização Fisiológica , Fibras Ópticas
12.
Talanta ; 271: 125648, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38219324

RESUMO

The high toxicity and occurrence of ochratoxin A (OTA) in grains and foods has been a growing concern due to the impacts on health and the economy in many countries. In this sense, simplified devices with high sensitivity and specificity for local monitoring are enthusiastically pursued. In this work, we report for the first time the detection of ochratoxin A in coffee samples using a spoon-shaped waveguide immunosensor. The biosensor was built with the surface of the spoon-shaped waveguide covered by a 60 nm layer of gold to enable the SPR phenomenon. The measurements indicated a linear relationship between the change in the SPR phenomenon values and the OTA concentration in the range from 0.2 ppt to 5 ppt. When analyzed in coffee samples, the biosensor was highly selective and did not suffer matrix interference. The developed biosensor represents a promising analytical device for coffee quality analyses, as it is portable, simple, and suitable for onsite detection of target analytes.


Assuntos
Técnicas Biossensoriais , Ocratoxinas , Café , Imunoensaio , Ocratoxinas/análise
13.
J Gastroenterol Hepatol ; 39(2): 346-352, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37931782

RESUMO

INTRODUCTION: Accurate assessment of invasion depth of early rectal neoplasms is essential for optimal therapy. We aimed to compare three-dimensional endorectal ultrasound (3D-ERUS) with magnification chromoendoscopy (MCE) regarding their accuracy in assessing parietal invasion depth (T). METHODS: Patients with middle and distal rectum neoplasms were prospectively included. Two providers blinded to each other's assessment performed 3D-ERUS and MCE, respectively. The T stage assessed through ERUS was compared to the MCE evaluation. The results were compared to the surgical specimen anatomopathological report. Sensitivity, specificity, accuracy, positive (PPV), and negative (NPV) predictive values were calculated for the T stage and for the final therapy (local excision or radical surgery). RESULTS: In 8 years, 70 patients were enrolled, and all underwent both exams. MCE and ERUS showed an accuracy of 94.3% and 85.7%, sensitivity of 83.7 and 93.3%, specificity of 96.4 and 83.6%, PPV of 86.7 and 60.9%, and NPV of 96.4 and 97.9%, respectively. Kappa for T stage assessed through ERUS was 0.64 and 0.83 for MCE. CONCLUSION: MCE and 3D-ERUS had good diagnostic performance, but the endoscopic method had higher accuracy. Both methods reliably assessed lesion extension, circumferential involvement, and distance from the anal verge.


Assuntos
Endossonografia , Neoplasias Retais , Humanos , Endossonografia/métodos , Estadiamento de Neoplasias , Neoplasias Retais/patologia , Ultrassonografia/métodos , Canal Anal
15.
BMC Musculoskelet Disord ; 24(1): 914, 2023 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-38012614

RESUMO

BACKGROUND: The self-perceived health status of patients undergoing total hip and knee arthroplasty (THA and TKA) might differ post-operatively due to gender, age, or comorbidities. Patient-reported outcome measures (PROMs) such as the EQ-5D-5L measure the self-perceived health status. This study investigates whether the index score of the EQ-5D-5L is a valid tool for interpreting gender differences in outcomes for patients undergoing THA and TKA. METHODS: Routine and PROM-data of elective primary THA or TKA patients in two German hospitals between 2016 and 2018 were analyzed. Univariate analysis with Pearson's chi-square was conducted to identify control variables for gender. To quantify the association between gender and the EQ-5D-5L dimensions, a cumulative odds ordinal logistic regression with proportional odds was conducted. RESULTS: Two thousand three hundred sixty-eight​​ THA patients (m = 978; f = 1390) and 1629 TKA patients (m = 715; f = 914) were considered. The regression analysis of the individual EQ-5D-5L dimensions showed that female gender was significantly associated with better self-care (THA and TKA) and better post-operative mobility (THA). In contrast, male gender was significantly associated with less pain/discomfort (TKA) and less anxiety/depression (THA) pre-surgery and 3-months post-surgery. CONCLUSION: Our results confirmed that the self-perceived health status improved after surgery. However, due to the different associations of gender to the individual dimensions of the EQ-5D-5L, the weighted index score clouds the comparability between patients with different gender undergoing THA or TKA. Therefore, we argue to use the individual five dimensions for health status analysis, to reveal relevant additional information.


Patients undergoing total hip and knee arthroplasty (THA and TKA) can fill out standardized questionnaires pre- and post-surgery, such as the EQ-5D-5L, to measure the improvement in the self-perceived health status. The EQ-5D-5L includes mobility, self-care, usual activity, pain/discomfort, and anxiety/depression. We do not know whether male and female patients experience the same improvement in the dimensions or whether significant differences exist. Currently, only index scores of the EQ-5D-5L are used for the comparison of pre- and post-operative health status. However, due to the questionnaire's weighted composition, relevant changes in individual dimensions might be easily missed. Thus, we investigated whether significant differences between gender and the EQ-5D-5L dimensions in patients undergoing TKA and TKA are observable. We found that female patients reported significantly better scores in self-care (THA and TKA) and post-operative mobility (THA). In contrast, male gender was significantly associated with less pain/discomfort (TKA) and less anxiety/depression (THA) pre-surgery and 3-months post-surgery. The EQ-5D-5L's weighted index score, however, does not directly represent these differences. Therefore, we argue to use the individual five dimensions for health status analysis, as relevant additional information on improvement over time would otherwise be missed.


Assuntos
Artroplastia de Quadril , Artroplastia do Joelho , Humanos , Masculino , Feminino , Artroplastia do Joelho/efeitos adversos , Artroplastia de Quadril/efeitos adversos , Qualidade de Vida , Estudos Retrospectivos , Nível de Saúde , Inquéritos e Questionários
16.
Cureus ; 15(10): e47920, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-38034146

RESUMO

We describe a case of a 28-year-old male who presented with general malaise, fatigue, anorexia, occasional epigastric pain, and vomiting a few days after a mild severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. Clinical evolution led to weight loss (6 kg in six months) and craving for salty foods. Physical examination revealed dehydration, hypotension, and hyperpigmentation of the skin and mucosal surfaces. Laboratory tests demonstrated normocytic normochromic anemia, acute kidney injury, hyperkalemia, hyponatremia, and compensated metabolic acidosis. Adrenal workup allowed us to establish a diagnosis of adrenal insufficiency (AI) due to autoimmune adrenalitis, considering findings of a low cortisol and positive 21-hydroxylase antibodies (21OH-Abs), as well as high serum renin and adrenocorticotropic hormone (ACTH). Atypical presentations and comorbidities may appear regarding coronavirus disease 2019 (COVID-19), such as the association between COVID-19 and the hypothalamic-pituitary-adrenal (HPA) axis, which may be affected in any patient with SARS-CoV-2 infection, thus making adrenal insufficiency a diagnosis to consider.

17.
Sensors (Basel) ; 23(17)2023 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-37687788

RESUMO

This paper presents the development and application of an optical fiber-embedded tendon based on biomimetic multifunctional structures. The tendon was fabricated using a thermocure resin (polyurethane) and the three optical fibers with one fiber Bragg grating (FBG) inscribed in each fiber. The first step in the FBG-integrated artificial tendon analysis is the mechanical properties assessment through stress-strain curves, which indicated the customization of the proposed device, since it is possible to tailor the Young's modulus and strain limit of the tendon as a function of the integrated optical fibers, where the coated and uncoated fibers lead to differences in both parameters, i.e., strain limits and Young's modulus. Then, the artificial tendon integrated with FBG sensors undergoes three types of characterization, which assesses the influence of temperature, single-axis strain, and curvature. Results show similarities in the temperature responses in all analyzed FBGs, where the variations are related to the heterogeneity on the polyurethane matrix distribution. In contrast, the FBGs embedded in the tendon presented a reduction in the strain sensitivity when compared with the bare FBGs (i.e., without the integration in the artificial tendon). Such results demonstrated a reduction in the sensitivity as high as 77% when compared with the bare FBGs, which is related to strain field distributions in the FBGs when embedded in the tendon. In addition, the curvature tests indicated variations in both optical power and wavelength shift, where both parameters are used on the angle estimation using the proposed multifunctional artificial tendon. To that extent, root mean squared error of around 3.25° is obtained when both spectral features are considered. Therefore, the proposed approach indicates a suitable method for the development of smart structures in which the multifunctional capability of the device leads to the possibility of using not only as a structural element in tendon-driven actuators and devices, but also as a sensor element for the different structures.

18.
J Colloid Interface Sci ; 652(Pt B): 2159-2166, 2023 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-37713952

RESUMO

HYPOTHESIS: Measuring rotational and translational Brownian motion of single spherical particles reveals dissipations due to the interaction between the particle and the environment. EXPERIMENTS: In this article, we show experiments where the in-plane translational and the two rotational drag coefficients of a single spherical Brownian particle can be measured. These particle drags are functions of the particle size and of the particle-wall distance, and of the viscous dissipations at play. We measure drag coefficients for Janus particles close to a solid wall and close to a lipid bilayer membrane. FINDINGS: For a particle close to a wall, we show that according to hydrodynamic models, particle-wall distance and particle size can be determined. For a particle partially wrapped by lipid membranes, in absence of strong binding interactions, translational and rotational drags are significantly larger than the ones of non-wrapped particles. Beside the effect of the membrane viscosity, we show that dissipations in the deformed membrane cap region strongly contribute to the drag coefficients.

19.
Clinics (Sao Paulo) ; 78: 100278, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37639912

RESUMO

Fecal Immunochemical Test (FIT) followed by a colonoscopy is an efficacious strategy to improve the adenoma detection rate and Colorectal Cancer (CRC). There is no organized national screening program for CRC in Brazil. The aim of this research was to describe the implementation of an organized screening program for CRC through FIT followed by colonoscopy, in an urban low-income community of São Paulo city. The endpoints of the study were: FIT participation rate, FIT positivity rate, colonoscopy compliance rate, Positive Predictive Values (PPV) for adenoma and CRC, and the rate of complications. From May 2016 to October 2019, asymptomatic individuals, 50-75 years old, received a free kit to perform the FIT. Positive FIT (≥ 50 ng/mL) individuals were referred to colonoscopy. 10,057 individuals returned the stool sample for analysis, of which (98.2%) 9,881 were valid. Women represented 64.8% of the participants. 55.3% of individuals did not complete elementary school. Positive FIT was 7.8% (776/9881). The colonoscopy compliance rate was 68.9% (535/776). There were no major colonoscopy complications. Adenoma were detected in 63.2% (332/525) of individuals. Advanced adenomatous lesions were found in 31.4% (165/525). CRC was diagnosed in 5.9% (31/525), characterized as adenocarcinoma: in situ in 3.2% (1/31), intramucosal in 29% (9/31), and invasive in 67.7% (21/31). Endoscopic treatment with curative intent for CRC was performed in 45.2% (14/31) of the cases. Therefore, in an urban low-income community, an organized CRC screening using FIT followed by colonoscopy ensued a high participation rate, and high predictive positive value for both, adenoma and CRC.


Assuntos
Colonoscopia , Neoplasias Colorretais , Detecção Precoce de Câncer , Sangue Oculto , Idoso , Feminino , Humanos , Pessoa de Meia-Idade , Adenocarcinoma/diagnóstico , Adenocarcinoma/cirurgia , Brasil , Neoplasias Colorretais/diagnóstico , Neoplasias Colorretais/cirurgia , Adenoma/diagnóstico , Adenoma/cirurgia , Masculino
20.
Adv Exp Med Biol ; 1423: 303-315, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37525058

RESUMO

Chronic stress and high levels of the main stress hormones, and glucocorticoids (GC), are implicated in susceptibility to brain pathologies such as depression and Alzheimer's disease (AD), as they promote neural plasticity damage and glial reactivity, which can lead to dendritic/synaptic loss, reduced neurogenesis, mood deficits, and impaired cognition. Moreover, depression is implicated in the development of AD with chronic stress being a potential link between both disorders via common neurobiological underpinnings. Hereby, we summarize and discuss the clinical and preclinical evidence related to the detrimental effect of chronic stress as a precipitator of AD through the activation of pathological mechanisms leading to the accumulation of amyloid ß (Aß) and Tau protein. Given that the modern lifestyle increasingly exposes individuals to high stress loads, it is clear that understanding the mechanistic link(s) between chronic stress, depression, and AD pathogenesis may facilitate the treatment of AD and other stress-related disorders.


Assuntos
Doença de Alzheimer , Humanos , Doença de Alzheimer/metabolismo , Peptídeos beta-Amiloides/metabolismo , Depressão , Proteínas tau/metabolismo , Glucocorticoides/efeitos adversos , Plasticidade Neuronal
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