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1.
Anal Bioanal Chem ; 2024 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-39251427

RESUMO

Rapid virus identification is crucial for preventing outbreaks. The COVID-19 pandemic has highlighted the critical nature of rapid virus detection. Here, we designed a label-free electrochemical biosensor modified with gold nanoparticles (AuNPs) to detect IgG antibodies from human serum, enabling rapid point-of-care diagnostics. AuNPs were synthesized and characterized. A multivariate optimization was carried out to determine the optimal condition for functionalizing AuNPs with anti-IgG. Subsequently, using a glassy carbon electrode (GCE), a modified AuNPs/GCE electrochemical biosensor was developed for IgG detection. The results indicated that AuNPs displayed a spherical morphology with a size distribution of 19.54 nm. Additionally, the zeta potential was recorded at -7.84 mV. Central composite design (CCD) analysis determined the optimal conditions for functionalizing AuNPs to be an anti-IgG concentration of 320 µg mL-1, a temperature of 25 °C, and pH of 7.4. The characterization study confirmed the successful synthesis and functionalization of AuNPs. Through electrochemical impedance spectroscopy measurement, the biosensor demonstrated a limit of detection (LOD) of 0.2 ng mL-1 and limit of quantification (LOQ) of 0.8 ng mL-1. Furthermore, tests in real samples showed the interaction between IgG antibodies in serum samples and AuNPs/GCE, confirming the biosensor's ability to detect and quantify IgG in clinical samples.

2.
Sci Rep ; 14(1): 21147, 2024 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-39256454

RESUMO

Ensuring artificial intelligence behaves in such a way that is aligned with human values is commonly referred to as the alignment challenge. Prior work has shown that rational agents, behaving in such a way that maximizes a utility function, will inevitably behave in such a way that is not aligned with human values, especially as their level of intelligence goes up. Prior work has also shown that there is no "one true utility function"; solutions must include a more holistic approach to alignment. This paper describes apprehensive agents: agents that are architected in such a way that their effective utility function is an aggregation of a partial utility function (built by designers, to be maximized) and an expectation of negative feedback on given states (reasoned about, to be minimized). Agents are also capable of performing a temporal reasoning process that approximates designers' intentions in function of environment evolution (a necessary feature for severe mis-alignment to occur). We show that an apprehensive agent, behaving rationally, leverages this internal approximation of designers' intentions to predict negative feedback, and, as a consequence, behaves in such a way that maximizes alignment, without actually receiving any external feedback. We evaluate this strategy on simulated environments that expose mis-alignment opportunities: we show that apprehensive agents are indeed better aligned than their base counterparts and, in contrast with extant techniques, chances of alignment actually improve as agent intelligence grows.

3.
An Acad Bras Cienc ; 96(suppl 1): e20240100, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39166613

RESUMO

The use of platelet-rich plasma (PRP) and adipose-derived stromal cells (ADSC) have been investigated as a form of wound healing enhancement. The objective of this work was to evaluate the association of red propolis (RP) and PRP as inducers of ADSC for application in tissue regeneration. Adipose tissue post-collection and post-cryopreservation was isolated with type II collagenase, characterized by flow cytometry, and differentiated into osteogenic, chondrogenic and adipose cell. The viability of ADSC was evaluated when exposed to different concentrations of RP using the MTT and trypan blue assay. Acridine orange and ethidium bromide (AO/EB) was performed to evaluate cell death events. Horizontal migration methods were investigated in ADSC using autologous and homologous PRP associated with RP (PRP/RP). All assays were processed in triplicate. Flow cytometry and cellular differentiation showed that type II collagenase was effective for isolating ADSC post-collection and post-cryopreservation. RP extracts at concentrations of up to 50 µg.mL-1 presented no cytotoxic effects. Association of PRP and RP at 25 and 50 µg.ml-1 influenced ADSC migration, with total closure on the seventh day after exposition. The results here presented could stimulate proliferation of ADSC cells that may contribute directly or indirectly to the reconstructive process of tissue regeneration.


Assuntos
Plasma Rico em Plaquetas , Própole , Células Estromais , Própole/farmacologia , Humanos , Células Estromais/efeitos dos fármacos , Citometria de Fluxo , Diferenciação Celular/efeitos dos fármacos , Terapia Baseada em Transplante de Células e Tecidos/métodos , Regeneração/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Tecido Adiposo/citologia , Sobrevivência Celular/efeitos dos fármacos , Movimento Celular/efeitos dos fármacos , Cicatrização/efeitos dos fármacos , Células Cultivadas
4.
Rev Esc Enferm USP ; 58: e20230398, 2024.
Artigo em Inglês, Português | MEDLINE | ID: mdl-39101809

RESUMO

OBJECTIVES: To describe the historical series of admissions to the Intensive Care Unit of older adults with femoral fractures, and verify the association between age and injury characteristics and treatment, nursing workload, severity, and clinical evolution in the unit. METHOD: Retrospective cohort of 295 older adults (age ≥60 years) admitted to the Intensive Care Unit of a hospital in São Paulo, between 2013 and 2019, and who presented with a femur fracture as the main cause of hospitalization. Variables regarding demographic characteristics, cause, and type of fracture, treatment provided, severity, nursing workload, and medical outcome of patients were analyzed. The Shapiro-Wilk, Wilcoxon-Mann-Whitney, Kruskal-Wallis tests and Pearson correlation were applied. RESULTS: There was an increase in older adults admission to the Intensive Care Unit from 2017 on. Female patients with distal femur fractures who died in the Intensive Care Unit had significantly (p < 0.05) higher median age than men, patients with shaft or proximal femur fractures, and survivors. CONCLUSION: The study findings highlight essential information for structuring care for older adults with femoral fractures who require intensive care.


Assuntos
Fraturas do Fêmur , Unidades de Terapia Intensiva , Humanos , Estudos Retrospectivos , Feminino , Masculino , Idoso , Unidades de Terapia Intensiva/estatística & dados numéricos , Pessoa de Meia-Idade , Idoso de 80 Anos ou mais , Estudos de Coortes , Fatores Etários , Hospitalização/estatística & dados numéricos , Brasil/epidemiologia , Fatores Sexuais , Admissão do Paciente/estatística & dados numéricos
5.
Commun Biol ; 7(1): 1062, 2024 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-39215205

RESUMO

Multiplexed imaging technologies have made it possible to interrogate complex tissue microenvironments at sub-cellular resolution within their native spatial context. However, proper quantification of this complexity requires the ability to easily and accurately segment cells into their sub-cellular compartments. Within the supervised learning paradigm, deep learning-based segmentation methods demonstrating human level performance have emerged. However, limited work has been done in developing such generalist methods within the unsupervised context. Here we present an easy-to-use unsupervised segmentation (UNSEG) method that achieves deep learning level performance without requiring any training data via leveraging a Bayesian-like framework, and nucleus and cell membrane markers. We show that UNSEG is internally consistent and better at generalizing to the complexity of tissue morphology than current deep learning methods, allowing it to unambiguously identify the cytoplasmic compartment of a cell, and localize molecules to their correct sub-cellular compartment. We also introduce a perturbed watershed algorithm for stably and automatically segmenting a cluster of cell nuclei into individual nuclei that increases the accuracy of classical watershed. Finally, we demonstrate the efficacy of UNSEG on a high-quality annotated gastrointestinal tissue dataset we have generated, on publicly available datasets, and in a range of practical scenarios.


Assuntos
Núcleo Celular , Aprendizado Profundo , Humanos , Aprendizado de Máquina não Supervisionado , Processamento de Imagem Assistida por Computador/métodos , Teorema de Bayes , Algoritmos
6.
JBI Evid Implement ; 2024 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-39045842

RESUMO

INTRODUCTION: Patients undergoing intubation and mechanical ventilation in an intensive care unit risk developing post-extubation oropharyngeal dysphagia (PED). PED can lead to aspiration complications, aspiration pneumonia, and prolonged hospitalization, as well as increased repeat intubation and in-hospital morbidity and mortality. OBJECTIVE: This evidence implementation project aimed to promote evidence-based screening and early detection of PED in an adult intensive care unit in a secondary public hospital in Brazil. METHOD: The project followed the seven-phase JBI Evidence Implementation Framework to promote changes at the study site. The JBI Practical Application of Clinical Evidence System (PACES) and Getting Research into Practice (GRiP) approach were also used. The project was developed considering the main barriers to best practices, which were identified through a baseline audit. An educational program was designed to address the identified barriers. Two follow-up audits were then conducted to assess the changes in compliance with the evidence-based practices. RESULTS: The baseline audit showed deficits in current practices. The first follow-up audit indicated improved compliance with best practices, with five of the seven audit criteria showing 100% compliance. The second follow-up audit indicated that compliance remained at 100% for those five criteria and increased for the other two after an additional intervention to address poor results in nursing care documentation. CONCLUSION: The first follow-up audit showed good adherence to the educational program for the screening and detection of PED by nurses. The second follow-up audit, in line with the new strategies, showed improvement in nursing documentation. SPANISH ABSTRACT: http://links.lww.com/IJEBH/A241.

7.
Neurol Genet ; 10(2): e200135, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38496361

RESUMO

Background and Objectives: Pathogenic variants in PI3K-AKT-mTOR pathway and GATOR1 complex genes resulting in hyperactivation of mechanistic target of rapamycin (mTOR) complex 1 are a major cause of drug-resistant epilepsy and focal cortical malformations (FCM). Resective neurosurgery is often required to achieve seizure control in patients with mTORopathies due to lack of effectiveness of nonsurgical therapies, including antiseizure medication and mTOR inhibitors. Elevated hyperpolarization-activated cyclic nucleotide-gated potassium channel isoform 4 (HCN4) has been proposed as a key marker in some mTOR-related brain malformations. This study aimed to investigate HCN4 as a biomarker in the brain across the genetic spectrum of mTORopathies in humans. Methods: Our study investigated the relative steady-state levels and cellular localization of HCN4 in resected human brain tissue from 18 individuals with mTORopathies (3 individuals with tuberous sclerosis complex (TSC) due to TSC2 variants, 5 individuals with focal cortical dysplasia type IIA (FCD IIA) due to genetic variants in MTOR, AKT3, and PIK3CA, and 10 individuals with FCD IIB due to variants in TSC1, MTOR, RHEB, DEPDC5, or NPRL3). Results: Elevated HCN4 was observed to be highly restricted to abnormal cell types (dysmorphic neurons and balloon cells) in brain tissue from all mTORopathy tissues (p < 0.0001) compared with those in controls, regardless of genetic cause or variant allele frequency. Elevated HCN4 was not observed in controls or individuals with non-mTOR-related focal epilepsy due to pathogenic variants in ATP1A3, SLC35A2, or FGFR1. Discussion: HCN4 provides a biomarker for the genetic spectrum of mTORopathies and may present a potential therapeutic target for seizure control in mTOR-related epilepsy.

8.
Int J Biometeorol ; 68(2): 229-236, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38012375

RESUMO

This study aimed to evaluate and compare the physiological performance of different genetic groups of sheep, by physiological variables and serum hormone levels, in a hot weather environment. Thirty sheep from five genetic groups were used: Santa Inês (SI), ½ Dorper + ½ Santa Inês (DO), ½ Ilê de France + ½ Santa Inês (IF), ½ Suffolk + ½ Santa Inês (SK), and ½ Texel + ½ Santa Inês (TX). The readings and records of physiological parameters (respiratory rate (RR), rectal temperature (RT), auricular cavity temperature (ACT), and surface temperature (ST)) were carried out at 7:00 am, 1:00 pm, and 7:00 pm, in 12 non-consecutive days. The collections of blood samples for hormone analysis (triiodothyronine (T3), thyroxine (T4), and cortisol (CORT)) is in four consecutive days. The environmental conditions of the experimental period caused a thermal discomfort in the sheep, but not a state of thermal stress. The thermolysis mechanisms, sensitive (ST and ACT) and latent (RR) processes, were enough to maintain their homeostasis (RT). The results showed that crossbred breeds presented a higher metabolism and were more efficient at dissipating heat through thermolysis than the SI breed. The crossbred breeds were efficient at dissipating heat through the elevation of body surface temperature and respiratory rate, mainly SK and TX, i.e., crossbred breeds, despite the wool cover, used thermoregulatory mechanisms that promoted lower variation of RT. The analysis of variance showed significant effects (P < 0.05) to the time factor in the responses of T4 and T3, and to the breed factor in the responses of CORT, T4, and T3. We did not observe interaction between the factors to any of the hormonal variables. Therefore, we can state that the effect of time was independent of breed and vice versa. Thyroid hormones presented lower blood concentration in the mornings (4.03 ± 0.82, T4; 65.08 ± 10.6, T3), increasing their concentration in the afternoon (4.60 ± 1.03, T4; 70.16 ± 14.17, T3). The thyroid hormones presented a normal circadian rhythm, with the exception of SK. Air temperature (AT) showed greater correlation with physiological variables than enthalpy (H) did, in the experimental conditions. However, H showed correlation with T4 and T3. The adaptive profile of the genetic groups under study are different, but the IF genetic group showed better performance under environmental conditions.


Assuntos
Regulação da Temperatura Corporal , , Ovinos/genética , Animais , Temperatura Corporal , Hormônios Tireóideos , Tri-Iodotironina
9.
Rev. Esc. Enferm. USP ; 58: e20230398, 2024. tab, graf
Artigo em Inglês | LILACS, BDENF - Enfermagem | ID: biblio-1569504

RESUMO

ABSTRACT Objectives: To describe the historical series of admissions to the Intensive Care Unit of older adults with femoral fractures, and verify the association between age and injury characteristics and treatment, nursing workload, severity, and clinical evolution in the unit. Method: Retrospective cohort of 295 older adults (age ≥60 years) admitted to the Intensive Care Unit of a hospital in São Paulo, between 2013 and 2019, and who presented with a femur fracture as the main cause of hospitalization. Variables regarding demographic characteristics, cause, and type of fracture, treatment provided, severity, nursing workload, and medical outcome of patients were analyzed. The Shapiro-Wilk, Wilcoxon-Mann-Whitney, Kruskal-Wallis tests and Pearson correlation were applied. Results: There was an increase in older adults admission to the Intensive Care Unit from 2017 on. Female patients with distal femur fractures who died in the Intensive Care Unit had significantly (p < 0.05) higher median age than men, patients with shaft or proximal femur fractures, and survivors. Conclusion: The study findings highlight essential information for structuring care for older adults with femoral fractures who require intensive care.


RESUMEN Objetivo: Describir la serie histórica de internaciones, en la Unidad de Cuidados Intensivos, de ancianos con fractura de fémur, y verificar la asociación entre la edad y las características y tratamiento de la lesión, carga de trabajo de enfermería, gravedad y evolución clínica en la unidad. Método: Cohorte retrospectiva de 295 ancianos (edad ≥60 años) ingresados en la Unidad de Cuidados Intensivos de un hospital de São Paulo, entre 2013 y 2019, y que presentaron fractura de fémur como principal causa de hospitalización. Se analizaron variables relativas a características demográficas, causa y tipo de fractura, tratamiento realizado, gravedad, carga de trabajo de enfermería y evolución clínica de los pacientes. Se aplicaron las pruebas de Shapiro-Wilk, Wilcoxon-Mann-Whitney, Kruskal-Wallis y correlación de Pearson. Resultados: Hubo aumento de hospitalizaciones de ancianos en Unidad de Cuidados Intensivos desde 2017. Las pacientes del sexo femenino con fracturas de fémur distal que murieron en la Unidad de Cuidados Intensivos tuvieron mediana de edad significativamente (p < 0,05) más alta que los hombres, los pacientes con fracturas de diáfisis o de fémur proximal y los supervivientes. Conclusión: Los hallazgos del estudio resaltan información esencial para estructurar la atención de los ancianos con fracturas femorales que requieren tratamiento intensivo.


RESUMO Objetivos: Descrever a série histórica das internações, na Unidade de Terapia Intensiva, de idosos com fratura de fêmur, e verificar a associação entre idade e as características e tratamento da lesão, carga de trabalho de enfermagem, gravidade e evolução clínica na unidade. Método: Coorte retrospectiva de 295 idosos (idade ≥60 anos) admitidos na Unidade de Terapia Intensiva de hospital em São Paulo, entre 2013 e 2019, e que apresentaram fratura de fêmur como causa principal da internação. Variáveis sobre características demográficas, causa e tipo da fratura, tratamento realizado, gravidade, carga de trabalho de enfermagem e desfecho clínico dos pacientes foram analisadas. Os testes de Shapiro-Wilk, Wilcoxon-Mann-Whitney, Kruskal-Wallis e correlação de Pearson foram aplicados. Resultados: Houve aumento das internações de idosos na Unidade de Terapia Intensiva a partir de 2017. Pacientes do sexo feminino, com fratura distal de fêmur e que morreram na Unidade de Terapia Intensiva apresentaram significativamente (p < 0,05) maior mediana de idade do que homens, pacientes com fratura de diáfise ou proximal do fêmur e sobreviventes. Conclusão: Os achados do estudo evidenciam informações essenciais para estruturação dos cuidados ao idoso com fratura de fêmur que necessita de tratamento intensivo.


Assuntos
Humanos , Masculino , Feminino , Idoso , Idoso de 80 Anos ou mais , Idoso , Enfermagem , Fraturas do Fêmur , Mortalidade , Carga de Trabalho , Unidades de Terapia Intensiva
10.
bioRxiv ; 2023 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-38014263

RESUMO

Multiplexed imaging technologies have made it possible to interrogate complex tumor microenvironments at sub-cellular resolution within their native spatial context. However, proper quantification of this complexity requires the ability to easily and accurately segment cells into their sub-cellular compartments. Within the supervised learning paradigm, deep learning based segmentation methods demonstrating human level performance have emerged. Here we present an unsupervised segmentation (UNSEG) method that achieves deep learning level performance without requiring any training data. UNSEG leverages a Bayesian-like framework and the specificity of nucleus and cell membrane markers to construct an a posteriori probability estimate of each pixel belonging to the nucleus, cell membrane, or background. It uses this estimate to segment each cell into its nuclear and cell-membrane compartments. We show that UNSEG is more internally consistent and better at generalizing to the complexity of tissue samples than current deep learning methods. This allows UNSEG to unambiguously identify the cytoplasmic compartment of a cell, which we employ to demonstrate its use in an example biological scenario. Within the UNSEG framework, we also introduce a new perturbed watershed algorithm capable of stably and accurately segmenting a cell nuclei cluster into individual cell nuclei. Perturbed watershed can also be used as a standalone algorithm that researchers can incorporate within their supervised or unsupervised learning approaches to replace classical watershed. Finally, as part of developing UNSEG, we have generated a high-quality annotated gastrointestinal tissue dataset, which we anticipate will be useful for the broader research community. Segmentation, despite its long antecedents, remains a challenging problem, particularly in the context of tissue samples. UNSEG, an easy-to-use algorithm, provides an unsupervised approach to overcome this bottleneck, and as we discuss, can help improve deep learning based segmentation methods by providing a bridge between unsupervised and supervised learning paradigms.

11.
J Chromatogr A ; 1711: 464466, 2023 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-37897923

RESUMO

Here, a novel nanohybrid material (Ag@CD@ANS) based on oat starch was produced, characterized, and applied to extract persistent organic pollutants in a shrimp sample. By the characterization experiments, Ag@CD@ANS was successfully synthesized. The functionalization of the material by 1,2-naphthoquinone-4-sulphonic acid (ANS) was confirmed using the infrared technique and CHN elemental analysis. The isotherm study showed that the material has a high adsorption capacity for the pesticides of interest (flutriafol, atrazine, heptachlor, DDT and bifenthrin) allowing their extraction from shrimp samples. The optimal condition for extraction was obtained using multivariate analysis. The nature of the elution solvent (hexane, methanol, acetonitrile) and the mass ratio between sample:adsorbent (1:1; 1:5 and 1:10) were the evaluated factors for extraction using Ag@CD@ANS and commercial adsorbents (neutral alumina, octadecyl, silica gel). From the multivariate analysis, it was observed that the optimal condition for pesticide extraction using Ag@CD@ANS was reached, using a 1:5 ratio (sample:adsorbent) and acetonitrile (10 mL) as elution solvent. For the commercial adsorbents, the optimal condition for pesticide extraction was reached, using a 1:3 ratio (sample:adsorbent), acetonitrile (10 mL) and neutral alumina as commercial adsorbent. Ag@CD@ANS efficiency was compared with an optimal commercial adsorbent (neutral alumina). No significant difference (p < 0.05) between neutral alumina and Ag@CD@ANS was observed. Recoveries ranging from 75 to 105 % with coefficients of variation ≤ 15 % (n = 3) were obtained using neutral alumina while using Ag@CD@ANS, recoveries ranging from 73 to 102 %, with coefficient of variation ≤ 13 % (n = 3) were obtained for the target pesticides. Limits of detection ranging from 0.5 to 1.0 µg Kg-1 and limits of quantification ranging from 1.6 to 3.3 µg Kg-1 were reached. The results demonstrated that Ag@CD@ANS can alternatively be used as a support for the extraction of persistent organic pollutants, having the advantage of being reusable for up to three cycles.


Assuntos
Poluentes Orgânicos Persistentes , Praguicidas , Solventes , Óxido de Alumínio , Acetonitrilas , Extração em Fase Sólida/métodos
12.
bioRxiv ; 2023 Aug 29.
Artigo em Inglês | MEDLINE | ID: mdl-37693407

RESUMO

Bifidobacteria commonly represent a dominant constituent of human gut microbiomes during infancy, influencing nutrition, immune development, and resistance to infection. Despite interest as a probiotic therapy, predicting the nutritional requirements and health-promoting effects of Bifidobacteria is challenging due to major knowledge gaps. To overcome these deficiencies, we used large-scale genetics to create a compendium of mutant fitness in Bifidobacterium breve (Bb). We generated a high density, randomly barcoded transposon insertion pool in Bb, and used this pool to determine Bb fitness requirements during colonization of germ-free mice and chickens with multiple diets and in response to hundreds of in vitro perturbations. To enable mechanistic investigation, we constructed an ordered collection of insertion strains covering 1462 genes. We leveraged these tools to improve models of metabolic pathways, reveal unexpected host- and diet-specific requirements for colonization, and connect the production of immunomodulatory molecules to growth benefits. These resources will greatly reduce the barrier to future investigations of this important beneficial microbe.

13.
Int J Biometeorol ; 67(10): 1651-1658, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37474668

RESUMO

A commercial low-profile cross-ventilated system (LPCV) free-stall barn with evaporative cooling pads on the air intake side was used to assess the potential of cross-ventilation with evaporative cooling to alleviate heat stress in lactating dairy cows. A total of 5712 records (238 days × 24 h) of air temperature (AT) and relative humidity (RH) values were collected. In order to state the effectiveness of the ventilation system and potential heat stress, the temperature humidity index (THI) and enthalpy (h) were calculated outside and inside the LPCV barn. The cooling capacity of the LPCV system is greater in conditions of low humidity, and the difference between the values of the internal and external temperature reached -12 °C. The LPCV reduced exposure to heat stress, increasing the time cows spent in thermoneutral conditions. This system could reduce the occurrence of temperature above 25 °C from 33 to 5% and 11% in sections A (represents the inlet side of the barn) and D (represents the outlet side of the barn), respectively. On the other hand, the LPCV kept a high and constant rate of RH throughout the day. The average inside and outside AT were significantly different, but differences in temperature were observed across the width of the barn. Analyzing the barn by the indexes, the THI showed that the barn promoted cows more time confined under non-stressful thermal conditions (between 83.8 and 90% vs 68.7%) and stress period much lower compared to the external environment (between 10 and 16.2% vs. 31.3%). The enthalpy index showed that there was not much difference between the internal and external environments. The LPCV system is another installation alternative for raising dairy cow in a hot and humid climate.


Assuntos
Transtornos de Estresse por Calor , Lactação , Feminino , Bovinos , Animais , Clima , Temperatura , Temperatura Corporal , Umidade , Transtornos de Estresse por Calor/prevenção & controle , Transtornos de Estresse por Calor/veterinária , Temperatura Alta
14.
PeerJ ; 11: e15393, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37250715

RESUMO

Background: The delimitation of cryptic species is a challenge for biodiversity conservation. Anurans show high cryptic diversity levels, and molecular species delimitation methods could help identify putative new species. Additionally, species delimitation approaches can provide important results for cryptic species conservation, with integrative methods adding robustness to results. Ischnocnema manezinho was described from Santa Catarina Island (SCI), southern Brazil. More recently, some inventories indicated continental populations supposedly similar in morphology to it. If these records are confirmed as I. manezinho, it would likely change its endangered status on National Red List, removing the species from conservation agendas. We investigated the threatened frog Ischnocnema manezinho, to evaluate if the continental populations belong to this species or if they form an undescribed species complex. Methods: We used coalescent, distance, and allele-sharing-based species delimitation methods and integrative analyses of morphometric and bioacoustics traits to test evolutionary independence between I. manezinho from SCI, Arvoredo Island, and continental populations. Results: Ischnocnema manezinho is restricted to Santa Catarina Island, while the five remaining lineages should be further investigated through a taxonomic review. Our results point to a small geographic range of Ischnocnema manezinho. Additionally, the species occurs in isolated fragments of forest in SCI surrounded by expanding urban areas, confirming its status as Endangered. Thus, the protection and monitoring of I. manezinho and the taxonomic description of the continental and Arvoredo Island candidate species should be priorities.


Assuntos
Anuros , Florestas , Animais , Filogenia , Anuros/genética , Biodiversidade , Folhas de Planta
15.
Front Pharmacol ; 14: 1159527, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37234718

RESUMO

Changes in Hyperpolarization-Activated Cyclic Nucleotide-Gated (HCN) channel function have been linked to depressive-like traits, making them potential drug targets. However, there is currently no peer-reviewed data supporting the use of a small molecule modulator of HCN channels in depression treatment. Org 34167, a benzisoxazole derivative, has been patented for the treatment of depression and progressed to Phase I trials. In the current study, we analysed the biophysical effects of Org 34167 on HCN channels in stably transfected human embryonic kidney 293 (HEK293) cells and mouse layer V neurons using patch-clamp electrophysiology, and we utilised three high-throughput screens for depressive-like behaviour to assess the activity of Org 34167 in mice. The impact of Org 34167 on locomotion and coordination were measured by performing rotarod and ledged beam tests. Org 34167 is a broad-spectrum inhibitor of HCN channels, slowing activation and causing a hyperpolarising shift in voltage-dependence of activation. It also reduced I h-mediated sag in mouse neurons. Org 34167 (0.5 mg/kg) reduced marble burying and increased the time spent mobile in the Porsolt swim and tail suspension tests in both male and female BALB/c mice, suggesting reduced depressive-like behaviour. Although no adverse effects were seen at 0.5 mg/kg, an increase in dose to 1 mg/kg resulted in visible tremors and impaired locomotion and coordination. These data support the premise that HCN channels are valid targets for anti-depressive drugs albeit with a narrow therapeutic index. Drugs with higher HCN subtype selectivity are needed to establish if a wider therapeutic window can be obtained.

16.
Environ Sci Pollut Res Int ; 30(28): 72319-72335, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37165270

RESUMO

The time data series of weather stations are a source of information for floods. The study of the previous wintertime series allows knowing the behavior of the variables and the result that will be applied to analysis and simulation models that feed variables such as flow and level of a study area. One of the most common problems is the acquisition and transmission of data from weather stations due to atypical values and lost data; this generates difficulties in the simulation process. Consequently, it is necessary to propose a numerical strategy to solve this problem. The data source for this study is a real database where these problems are presented with different variables of weather. This study is based on comparing three methods of time series analysis to evaluate a multivariable process offline. For the development of the study, we applied a method based on the discrete Fourier transform (DFT), and we contrasted it with methods such as the average and linear regression without uncertainty parameters to complete missing data. The proposed methodology entails statistical values, outlier detection, and the application of the DFT. The application of DFT allows the time series completion, based on its ability to manage various gap sizes and replace missing values. In sum, DFT led to low error percentages for all the time series (1% average). This percentage reflects what would have likely been the shape or pattern of the time series behavior in the absence of misleading outliers and missing data.


Assuntos
Tempo (Meteorologia) , Fatores de Tempo , Colômbia , Modelos Lineares , Simulação por Computador
17.
J Healthc Eng ; 2023: 6401673, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36818385

RESUMO

Internet of Things (IoT) technologies allow building a digital representation of people, objects, or physical phenomena to be available on the Internet. Thus, stakeholders can access this information from remote places or computational systems could analyze this data to find patterns, make decisions, or execute actions. For instance, a doctor could diagnose patients by analyzing the received data from an IoT system even when patients are located in a remote place. This article proposes an IoT system for monitoring electrocardiogram (ECG) signal and processing heart data in order to generate an alert when an arrhythmia is present. This system involves a Polar H10 heart sensor, machine-learning models to classify heart events, and communication technology to share and store patient's information. In the first place, the architecture of the IoT monitoring system and the communication between the components are described by discussing the designing criteria. Second, the experimentation process performs the training and the assessment of three classification algorithms, random forest, convolutional neural network, and k-nearest neighbors. The results show that k-nearest neighbor has the best accuracy percentage classifying the arrhythmias under study (premature ventricular contraction 94%, fusion of ventricular beat 81%, and supraventricular premature beat 82%); also, it is able to discern normal and unclassifiable beats with 93% and 97%, respectively.


Assuntos
Internet das Coisas , Complexos Ventriculares Prematuros , Humanos , Algoritmos , Redes Neurais de Computação , Aprendizado de Máquina
18.
J Neurosci ; 43(12): 2199-2209, 2023 03 22.
Artigo em Inglês | MEDLINE | ID: mdl-36813574

RESUMO

Pathogenic variants in HCN1 are associated with a range of epilepsy syndromes including a developmental and epileptic encephalopathy. The recurrent de novo HCN1 pathogenic variant (M305L) results in a cation leak, allowing the flux of excitatory ions at potentials where the wild-type channels are closed. The Hcn1M294L mouse recapitulates patient seizure and behavioral phenotypes. As HCN1 channels are highly expressed in rod and cone photoreceptor inner segments, where they shape the light response, mutated channels are likely to impact visual function. Electroretinogram (ERG) recordings from male and female mice Hcn1M294L mice revealed a significant decrease in the photoreceptor sensitivity to light, as well as attenuated bipolar cell (P2) and retinal ganglion cell responses. Hcn1M294L mice also showed attenuated ERG responses to flickering lights. ERG abnormalities are consistent with the response recorded from a single female human subject. There was no impact of the variant on the structure or expression of the Hcn1 protein in the retina. In silico modeling of photoreceptors revealed that the mutated HCN1 channel dramatically reduced light-induced hyperpolarization, resulting in more Ca2+ flux during the response when compared with the wild-type situation. We propose that the light-induced change in glutamate release from photoreceptors during a stimulus will be diminished, significantly blunting the dynamic range of this response. Our data highlight the importance of HCN1 channels to retinal function and suggest that patients with HCN1 pathogenic variants are likely to have a dramatically reduced sensitivity to light and a limited ability to process temporal information.SIGNIFICANCE STATEMENT Pathogenic variants in HCN1 are emerging as an important cause of catastrophic epilepsy. HCN1 channels are ubiquitously expressed throughout the body, including the retina. Electroretinogram recordings from a mouse model of HCN1 genetic epilepsy showed a marked decrease in the photoreceptor sensitivity to light and a reduced ability to respond to high rates of light flicker. No morphologic deficits were noted. Simulation data suggest that the mutated HCN1 channel blunts light-induced hyperpolarization and consequently limits the dynamic range of this response. Our results provide insights into the role HCN1 channels play in retinal function as well as highlighting the need to consider retinal dysfunction in disease caused by HCN1 variants. The characteristic changes in the electroretinogram open the possibility of using this tool as a biomarker for this HCN1 epilepsy variant and to facilitate development of treatments.


Assuntos
Epilepsia , Canais Disparados por Nucleotídeos Cíclicos Ativados por Hiperpolarização , Humanos , Masculino , Feminino , Camundongos , Animais , Canais Disparados por Nucleotídeos Cíclicos Ativados por Hiperpolarização/genética , Canais Disparados por Nucleotídeos Cíclicos Ativados por Hiperpolarização/metabolismo , Canais de Cátion Regulados por Nucleotídeos Cíclicos/metabolismo , Retina/metabolismo , Eletrorretinografia , Epilepsia/metabolismo , Células Fotorreceptoras Retinianas Cones/metabolismo , Canais de Potássio/fisiologia
19.
J Anim Ecol ; 92(2): 324-337, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36059124

RESUMO

Studying species interactions in nature often requires elaborated logistics and intense fieldwork. The difficulties in such task might hinder our ability to answer questions on how biotic interactions change with the environment. Fortunately, a workaround to this problem lies within scientific collections. For some animals, the inspection of preserved specimens can reveal the scars of past antagonistic encounters, such as predation attempts. A common defensive behaviour that leaves scars on animals is autotomy, the loss of a body appendage to escape predation. By knowing the collection site of preserved specimens, it is possible to assess the influence of organismal biology and the surrounding environment in the occurrence of autotomy. We gathered data on tail loss for 8189 preserved specimens of 33 snake and 11 amphisbaenian species to investigate biological and environmental correlates of autotomy in reptiles. We applied generalized linear mixed effect models to evaluate whether body size, sex, life-stage, habitat use, activity pattern, biome, tropicality, temperature and precipitation affect the probability of tail loss in limbless reptiles. We observed autotomy in 23.6% of examined specimens, with 18.7% of amphisbaenian and 33.4% of snake specimens showing tail loss. The probability of tail loss did not differ between snakes and amphisbaenians, but it was higher among large-sized specimens, particularly in adults and females. Chance of tail loss was higher for diurnal and arboreal species, and among specimens collected in warmer regions, but it was unaffected by biome, precipitation, and tropicality. Autotomy in limbless reptiles was affected by size-dependent factors that interplay with ontogeny and sexual dimorphism, although size-independent effects of life-stage and sex also shaped behavioural responses to predators. The increase in probability of tail loss with verticality and diurnality suggests a risk-balance mechanism between species habitat use and activity pattern. Although autotomy is more likely in warmer regions, it seems unrelated to seasonal differences in snakes and amphisbaenians activity. Our findings reveal several processes related to predator-prey interactions involving limbless reptiles, demonstrating the importance of scientific collections to unveil ecological mechanisms at different spatio-temporal scales.


Assuntos
Lagartos , Feminino , Animais , Lagartos/fisiologia , Cauda/fisiologia , Comportamento Predatório , Cicatriz , Ecossistema
20.
Appl Immunohistochem Mol Morphol ; 31(2): 69-76, 2023 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-36508180

RESUMO

We assessed CD8 + T-cell density in 351 resected stage II to III colon cancers from 2011 to 2015 and correlated the findings with disease-free survival and survival effect of adjuvant chemotherapy. Most tumors (70%) had high/intermediate CD8 + T-cell density, and this was significantly associated with mismatch repair deficiency compared with tumors with low CD8 + T-cell density (28% vs. 13%, P =0.003). Fewer tumors with high/intermediate CD8 + T-cell density had adverse histologic features compared with tumors with low CD8 + T-cell density including high tumor budding (16% vs. 27%) and venous (22% vs. 35%), lymphatic (54% vs. 65%), and perineural (23% vs. 33%) invasion (all with P <0.05). In the stage III cohort, high/intermediate CD8 + T-cell density was an independent predictor of disease-free survival on multivariate analysis (hazard ratio: 0.39, 0.21 to 0.71 95% CI, P =0.002). For stage III patients with high/intermediate CD8 + T-cell density, adjuvant chemotherapy was significantly associated with improved disease-free survival (hazard ratio: 0.28, 0.11 to 0.74 95% CI, P =0.01) whereas stage III patients with low CD8 + T-cell density did not have improved survival with adjuvant chemotherapy. In conclusion, in stage III colon cancer, CD8 + T-cell density is an independent prognostic biomarker for disease-free survival and may help to identify patients who benefit from adjuvant chemotherapy.


Assuntos
Linfócitos T CD8-Positivos , Quimioterapia Adjuvante , Neoplasias do Colo , Neoplasias Colorretais , Humanos , Linfócitos T CD8-Positivos/patologia , Neoplasias do Colo/patologia , Neoplasias do Colo/terapia , Neoplasias Colorretais/patologia , Neoplasias Colorretais/terapia , Intervalo Livre de Doença , Estadiamento de Neoplasias , Modelos de Riscos Proporcionais , Estudos Retrospectivos
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