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1.
Mol Biochem Parasitol ; 260: 111650, 2024 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-39151473

RESUMO

Most protocols used to study the dynamics of calcium (Ca2+) in the malaria parasite are based on dyes, which are invasive and do not allow discrimination between the signal from the host cell and the parasite. To avoid this pitfall, we have generated a parasite line expressing the genetically encoded calcium sensor GCaMP3. The PfGCaMP3 parasite line is an innovative tool for studying spontaneous intracellular Ca2+ oscillations without external markers. Using this parasite line, we demonstrate the occurrence of spontaneous Ca2+ oscillations in the ring, trophozoite, and schizont stages in Plasmodium falciparum. Using the Fourier transform to fluorescence intensity data extracted from different experiments, we observe cytosolic Ca2+ fluctuations. These spontaneous cytosolic Ca2+ oscillations occur in the three intraerythrocytic stages of the parasite, with most oscillations occurring in the ring and trophozoite stages. A control parasite line expressing only a GFP control did not reveal such fluctuations, demonstrating the specificity of the observations. Our results clearly show dynamic, spontaneous Ca2+ oscillations during the asexual stage in P. falciparum, independent from external stimuli.

2.
Sensors (Basel) ; 24(15)2024 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-39123868

RESUMO

Social interactions are characterized by being very diverse and changing over time. Understanding this diversity and dynamics, as well as their emerging patterns, is of great interest from social, health, and educational perspectives. The development of new devices has been made possible in recent years by advances in applied technology. This paper presents the design and development of a novel device composed of several sensors. Specifically, we propose a proximity sensor integrated by three devices: a Bluetooth sensor, a global positioning system (GPS) unit and an accelerometer. By means of this sensor it is possible to detect the presence of neighboring sensors in various configurations and operating conditions. Profiles based on the Received Signal Strength Indicator (RSSI) exhibit behavior consistent with that reported by empirical relationships. The present sensor is functional in detecting the proximity of other sensors and is thus useful for the identification of interactions between people in relevant contexts such as schools.

3.
J Food Sci ; 2024 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-39126699

RESUMO

Time-temperature data for queso fresco (QF) cheese varieties stored in a residential refrigerator operating at 5°C and a predictive microbiology secondary model for Listeria monocytogenes in QF were used to estimate a refrigerator performance indicator (RPI) of microbial preservation. RPI values were used to assess how compressor technology (single [SS] and variable speed [VS]), ambient temperature (21.1°C [LT] and 32.2°C [HT]), and refrigerator load (22.5 kg regular load and 39 kg higher load) affected preservation performance. All deterministic and probabilistic RPI estimations slightly exceeded the desirable 1.0 value, i.e., the variable temperatures for the QF kept in the refrigerator were worse than keeping it constantly at the temperature recommended by food safety agencies for QF. Furthermore, the mean comparison of estimates of the time-temperature equivalent indicator previously developed by French researchers showed similar behavior to those observed for RPI. Finally, statistical analysis showed that Tambient was the factor with the highest impact on refrigerator performance because of its impact on the sample temperature increase during door openings and when exposed to ambient temperature during product use. This highlights the need to reduce the time for product temperature recovery by improving the compressor operation logic. Also important are consumer behavior changes such as a reduction in product exposure to ambient temperature and in the door opening duration and frequency. PRACTICAL APPLICATION: This study demonstrated how a quantitative tool (RPI) can assess refrigerator preservation performance. Although the findings presented can be applied to any cold chain segment, the data used was collected for its weakest link, the domestic refrigerator. Surveys show that 77% of them operate above the recommended 4°C. The RPI methodology is ready for use by refrigerator designers to assess performance improvements possible by modifications of the compressor operation logic. Moreover, it can be integrated into smart-hubs monitoring the frequency and duration of refrigerator door openings to inform consumers when their habits are compromising the preservation performance of the refrigerator.

4.
Data Brief ; 55: 110692, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-39071959

RESUMO

This paper describes a data collection experiment focused on researching indoor positioning systems using Bluetooth Low Energy (BLE) devices. The study was conducted in a real-world scenario with 150 test points and collected signals from 11 mobile devices. The dataset contains RSSI values from the mobile devices in relation to 15 fixed anchor nodes in the experimentation scenario. The dataset includes data on device identification, labels and coordinates of test points, and the room where the data was collected. The data is organized as CSV files and offers valuable information for researchers developing and assessing location models. By sharing this dataset, we aim to support the creation of robust and precise indoor localization models.

5.
Ther Adv Endocrinol Metab ; 15: 20420188241252546, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38827386

RESUMO

Introduction: There are multiple mechanisms by which HbA1c values can be altered in chronic kidney disease (CKD), which limits its usefulness as a strategy to assess glycemic control in this population. Methods: Concordance and agreement study between two diagnostic tests: HbA1c and glucose management indicator (GMI) measured by intermittently scanned continuous glucose monitoring (isCGM), based in a prospective cohort of patients with diabetes, CKD (glomerular filtration rate between 15 and 60 ml/min/1.73 m²), and anemia. The isCGM was performed for 3 months, and the GMI was compared with the HbA1c levels taken at the end of isCGM. Agreement was evaluated using Bland-Altman graph analysis and Lin's concordance correlation coefficient (CCC). The concordance of the measures with good glycemic control (<7%) was also evaluated. Results: A total of 74 patients were enrolled (median age 68.5 years, 51.3% female, 64.9% with CKD stage 3, hemoglobin 11.1 ± 1.2 g/l). The Bland-Altman analysis shows a mean difference between GMI and HbA1c of 0.757 ± 0.687% (95% limits of agreement: -0.590 and 2.105). Difference was greater as the values of GMI and HbA1c increased. The agreement was poor [CCC 0.477; 95% confidence interval (CI): 0.360-0.594], as well as the concordance of values with good glycemic control according to GMI versus HbA1c (67.5% versus 29.7%, p < 0.001) (Kappa 0.2430; 95% CI: 0.16-0.32). Conclusion: The HbA1c overestimates the GMI values with highly variable ranges of difference, which prevents a precise correction factor. isCGM probably is a safer option for monitoring and decision-making in this population, especially in patients treated with insulin where the risk of hypoglycemia is greater.

6.
Environ Sci Pollut Res Int ; 31(22): 32060-32071, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38648005

RESUMO

The Sr/Ca and 87Sr/86Sr ratios are used as natural indicators (geomarkers) in fish to reveal migratory patterns, due to significant relationships between these ratios measured in the water and in the fish calcified structures (otoliths, bones). The aim of this study was to assess the potential use of the Limnoperna fortunei shell as a proxy for monitoring the spatial and temporal variability of Sr/Ca and 87Sr/86Sr in water. These ratios were compared in water samples and bivalve shells proceeding from eight sites of four hydrogeological regions of the La Plata Basin (Argentina and Uruguay), collected in two hydrological periods (winter and summer) in order to depict the pattern of geographical and temporal variability and to evaluate the relationship between both matrices. Significant positive linear relationships were found between shell edge and water for 87Sr/86Sr (R2 = 0.96-0.97, p < 0.005) and Sr/Ca (R2 = 0.83-0.86, p < 0.05) in summer and winter. Slopes did not differ significantly from 1 (p > 0.05) for 87Sr/86Sr, while they differed from 1 for Sr/Ca in both seasons (p < 0.05), indicating that the elemental ratio would be influenced by endogenous/exogenous factors. No significant seasonal differences were found for both natural tags (p > 0.05), except for the lower Uruguay River (87Sr/86Sr) and outer estuary (Sr/Ca). These results indicate that the L. fortunei shell could be a valuable tool for monitoring spatio-temporal variations in water 87Sr/86Sr. Shell Sr/Ca shows high potential utility as a geomarker in freshwater, but additional assessments are needed to understand the impact of temperature and growth on this ratio.


Assuntos
Bivalves , Monitoramento Ambiental , Animais , Monitoramento Ambiental/métodos , Estações do Ano , Argentina , Uruguai
7.
Explor Res Clin Soc Pharm ; 14: 100441, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38665264

RESUMO

Background: Key performance indicators (KPIs) are a set of indicators that improve the quality of services provided by pharmacists. They enable the monitoring and evaluation of result progress and optimize decision-making for stakeholders. Currently, there is no systematic review regarding KPIs for pharmaceutical services. Objectives: To identify and assess the quality of KPIs developed for pharmaceutical services. Methods: A systematic review was conducted in PubMed, Scopus, EMBASE, and LILACS from the inception of the database until February 5th, 2024. Studies that developed a set of KPIs for pharmaceutical services were included. The indicators were evaluated using the Appraisal of Indicators through Research and Evaluation (AIRE) instrument. Two independent reviewers performed the study selection, data extraction, and quality assessment. Results: Fifteen studies were included. The studies were conducted in different regions, most of which were developed for clinical services in hospitals or ambulatory settings, and used similar domains for the development of KPIs such as medication review, patient safety, and patient counseling. Literature review combined with the Delphi technique was the method most used by the studies, with content validity by inter-rater agreement. Regarding methodological quality, most studies described information on the purpose, definition, and stakeholders' involvement in the set of KPIs. However, little information was observed on the strategy for risk adjustment, instructions for presenting and interpreting the indicator results, the detailed description of the numerator and denominator, evidence scientific, and the feasibility of the set of KPIs. Only one study achieved a high methodological quality in all domains of the AIRE tool. Conclusion: Our findings showed the potential of KPIs to monitor and assess pharmacy practice quality. Future studies should expand KPIs for other settings, explore validity evidence of the existing KPIs, provide detailed descriptions of evidence, formulation, and usage, and test their feasibility in daily practice.

8.
Braz J Microbiol ; 55(2): 1703-1714, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38592593

RESUMO

The microbiological quality of meat is influenced by the conditions of hygiene prevailing during production and handling. Thus, this study aimed to assess the prevalence of Salmonella enterica and its antimicrobial resistance, load of hygiene indicator bacteria including E. coli (ECC), coliforms (CC), total coliform (TCC), Enterobacteriaceae (EB) and aerobic plate count (APC), and meat handler's food safety knowledge and hygiene practices in butcher shops in two cities, Addis Ababa and Hawassa in Ethiopia, during 2020 and 2021. A total of 360 samples of beef carcasses (n = 120), knives (n = 60), chopping boards (n = 60), weighing balance (n = 60), and personnel's hands (n = 60) were randomly collected for microbial analysis. Besides, 120 participants were selected to participate in a food safety knowledge and hygiene practices assessment. The S. enterica isolates were identified by agglutination test followed by qPCR targeting invA gene. Phenotypic antimicrobial resistance profiles of S. enterica were determined using disk diffusion assays as described in CLSI. The ECC, CC, TCC, EB, and APC populations were quantified by plating onto petrifilm plates. A structured questionnaire was used to determine food safety knowledge and hygiene practices of participants. Overall prevalence of S. enterica was 16.7% (95% CI, 8.3-26.7) and location seems to have no effect (p = 0.806). Only 20% of the S. enterica were resistant to ampicillin and tetracycline. However, the majority (80%) of S. enterica isolates were susceptible to the panel of 11 antimicrobials tested. The overall mean ± SD (log CFU/cm2) of ECC, CC, TCC, EB, and APC were 4.31 ± 1.15; 4.61 ± 1.33; 4.77 ± 1.32; 4.59 ± 1.38 and 5.87 ± 1.52, respectively. No significant difference (p = 0.123) in E. coli contamination was observed between samples of beef carcasses and chopping boards. The EB contamination showed no significant difference (p > 0.05) among sample sources. The APC contamination levels on beef carcass were significantly higher (p > 0.05) than other sample sources. A total of 56% (95% CI: 46.7 - 65.0) of the participants had poor knowledge and 65% (95% CI: 56.7 - 73.3) had poor hygiene practices towards food safety. This study highlighted the poor hygiene status of butcher facilities with a potential risk of beef safety. Thus, appropriate food safety control strategies and inspection is needed at retail establishments.


Assuntos
Antibacterianos , Farmacorresistência Bacteriana , Higiene , Salmonella enterica , Etiópia/epidemiologia , Salmonella enterica/efeitos dos fármacos , Salmonella enterica/genética , Salmonella enterica/isolamento & purificação , Animais , Bovinos , Humanos , Antibacterianos/farmacologia , Microbiologia de Alimentos , Carne Vermelha/microbiologia , Adulto , Inocuidade dos Alimentos , Manipulação de Alimentos , Masculino , Feminino , Testes de Sensibilidade Microbiana , Adulto Jovem
9.
Polymers (Basel) ; 16(6)2024 Mar 17.
Artigo em Inglês | MEDLINE | ID: mdl-38543434

RESUMO

In this work, a colorimetric indicator based on gold nanoparticles (AuNP) and a biodegradable and eco-friendly polymer (sodium alginate, Alg.), was developed for the real-time detection of fish spoilage products. The AuNPs and the colorimetric indicator were characterized using UV-VIS, FTIR spectroscopies, TGA, DSC, XRD, TEM, and colorimetry. The UV-VIS spectrum and TEM showed the successful synthesis, the spherical shape, and the size of AuNPs. The results indicated color changes of the indicator in packaged fish on day 9 of storage at a refrigerated temperature (5 °C. These results showed the successful application of the colorimetric indicator in the detection of TVB-N in packaged fish.

10.
Int J Biol Macromol ; 263(Pt 1): 130513, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38428758

RESUMO

Anthocyanins (ACNs) are natural compounds with potential applications due to their colorimetric response to pH. Due to their sensitivity to various environmental factors, nanoencapsulation with biopolymers is a successful strategy for stabilizing ACNs. In this work ACNs were extracted from grape skins and encapsulated into chitosan (CS) nanoparticles by ionic gelation using sodium tripolyphosphate (TPP) as a cross-linking agent. CS nanoparticles loaded with ACNs had particle sizes between 291 and 324 nm and polydispersity index around 0.3. The encapsulation efficiency of ACNs was approximately 60 %; and encapsulated anthocyanins (ACN-NPs) exhibited color change properties under different pH conditions. pH-sensitive labels based on polyvinyl alcohol (PVA) were prepared by the casting method. The effect of incorporating ACN-NPs on the physical, structural, and pH-sensitive properties of PVA labels was evaluated, and its application as shrimp freshness indicator was studied. The nanoencapsulation protected ACNs against heat and light treatments, preserving the original purple color. When applying the label, visible changes from red to blue until reaching yellow were observed with the change in the quality of the shrimp at the refrigeration temperature. The results suggest that PVA labels containing ACNs encapsulated in C-NPs can be used as smart packaging labels in the food industry.


Assuntos
Quitosana , Nanopartículas , Vitis , Quitosana/química , Álcool de Polivinil/química , Antocianinas/química , Nanopartículas/química , Extratos Vegetais/química , Embalagem de Alimentos/métodos , Concentração de Íons de Hidrogênio
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