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1.
J Trace Elem Med Biol ; 85: 127473, 2024 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-38795413

RESUMO

INTRODUCTION: Zinc (Zn) deficiency has been described not only on general human health but also within the sports context -as negatively affecting performance-. Thus, Zn status assessment is of great interest for athletes, especially in order to correct deficiency states of this mineral. OBJECTIVE: The overall objective of this work was to assess Zn status in professional handball players during the competitive period (through plasma levels, dietary intake and gene expression of the Zn transporters), as well as to determine the effect of Zn supplementation. METHODS: A total of twenty-two participants were recruited, -twelve belonged to the Control Group (CG) and ten male handball players comprised the experimental group (ATH-G)-, being monitored over a 2-month period with 2 evaluation moments: baseline (i.e., initial conditions) and follow-up (i.e., after 8 weeks of training and competition). Zn intake, plasma Zn levels, and gene expression of Zn transporters were obtained. RESULTS: Plasma Zn levels were higher in ATH-G than in CG at the end of Zn intervention (p ≤ 0.010). Moreover, differences in the gene expression profile of Zn transporters were observed in ATH-G -with the down-regulation of several Zn transporters-, compared to the CG at baseline (p ≤ 0.05). Likewise, differences in the Zn transporters expression were observed in ATH-G at 8 weeks (all, p ≤ 0.001) -with ZnT2, ZnT5, ZIP3, ZIP5, ZIP11, ZIP13 and ZIP14 transporters being up-regulated-. CONCLUSION: Handball players seemed to have different nutritional needs for Zn, with differences in the gene expression of Zn transporters compared to controls. Zn intervention in our athletes may have influenced the expression of Zn transporters, indicating a potential increase in Zn transporters expression to mobilize Zn at the cellular level at 8 weeks of Zn intervention.

2.
Fam Cancer ; 2024 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-38753287

RESUMO

The Spanish Familial Pancreatic Cancer Registry (PANGENFAM) was established in 2009 and aims to characterize the genotype and phenotype of familial pancreatic cancer (FPC). Furthermore, an early detection screening program for pancreatic ductal adenocarcinoma (PDAC) is provided to healthy high-risk individuals from FPC and hereditary pancreatic cancer families (first-degree relatives). This article describes our experience over the last 10 years in high-risk screening. Hereditary and familial pancreatic cancer families were identified through the oncology and gastroenterology units. High-risk individuals underwent annual screening with endoscopic ultrasound (EUS) and magnetic resonance (MRI) from age 40 or 10 years younger than the youngest affected family member. Results: PANGENFAM has enrolled 290 individuals from 143 families, including 52 PDAC cases and 238 high-risk individuals. All high-risk individuals eligible for screening were offered to enter the surveillance program, with 143 currently participating. Pancreatic abnormalities were detected in 94 individuals (median age 53 years (29-83), with common findings including cystic lesions and inhomogeneous parenchyma. Imaging test concordance was 66%. Surgical intervention was performed in 4 high-risk individuals following highly suspicious lesions detected by imaging. PANGENFAM is a valuable resource for science innovation, such as biobanking, with clinical and imaging data available for analysis. For high-risk families, it may offer a potential for early diagnosis. Collaboration with other national and international registries is needed to increase our understanding of the disease biology and to standardize criteria for inclusion and follow-up, optimizing cost-effectiveness and efficacy.

3.
Fam Cancer ; 2024 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-38780705

RESUMO

Pancreatic ductal adenocarcinoma (PDAC) is the fourth leading cause of cancer-related death in the Western world. The number of diagnosed cases and the mortality rate are almost equal as the majority of patients present with advanced disease at diagnosis. Between 4 and 10% of pancreatic cancer cases have an apparent hereditary background, known as hereditary pancreatic cancer (HPC) and familial pancreatic cancer (FPC), when the genetic basis is unknown. Surveillance of high-risk individuals (HRI) from these families by imaging aims to detect PDAC at an early stage to improve prognosis. However, the genetic basis is unknown in the majority of HRIs, with only around 10-13% of families carrying known pathogenic germline mutations. The aim of this study was to assess an individual's genetic cancer risk based on sex and personal and family history of cancer. The Best Linear Unbiased Prediction (BLUP) methodology was used to estimate an individual's predicted risk of developing cancer during their lifetime. The model uses different demographic factors in order to estimate heritability. A reliable estimation of heritability for pancreatic cancer of 0.27 on the liability scale, and 0.07 at the observed data scale as obtained, which is different from zero, indicating a polygenic inheritance pattern of PDAC. BLUP was able to correctly discriminate PDAC cases from healthy individuals and those with other cancer types. Thus, providing an additional tool to assess PDAC risk HRI with an assumed genetic predisposition in the absence of known pathogenic germline mutations.

4.
J Hum Kinet ; 92: 147-159, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38736594

RESUMO

The present study aimed to analyse the relationship between functional movement and strength variables upon linear speed (Ls) and change of direction (COD) based on gender. It also aimed to identify the determinants of performance of Ls and COD according to gender. Fifty basketball players (54% female) completed the assessment in which the weight-bearing dorsiflexion test, the Y-balance test, the unilateral countermovement jump, the unilateral drop jump, the unilateral triple hop test, Ls and CODs were performed. Speed variables were divided according to time execution into "low-performance" and "high-performance" to establish a comparison between performance groups. Strength variables significantly influenced speed tests' performance in both genders (p < 0.05). For males, the greater the Ls, the higher the change of direction deficit (p < 0.001). Multiple regression analysis revealed that a long and vertical stretch-shortening cycle (SSC) was the most influential physical ability for speed performance in females (45-65% variance explained; p < 0.001), while in males, a short and horizontal SSC played a significant role (30-61% variance explained; p < 0.022). These results suggest that gender should be considered in programming strength training to improve speed, as each gender will benefit most from the application of different force-orientations and different SSC. Also, the faster the male players were in Ls, the less efficient they were in the COD performance. This is why for men, it would be recommended to perform eccentric exercises along with deceleration and technique drills to improve COD speed.

5.
J Sports Sci ; : 1-8, 2024 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-38739494

RESUMO

Change of direction deficit (CODD) offers valuable insights into a player's balance between linear and multidirectional speed. However, there are still no established reference values for CODD. The objectives of this study were to determine CODD thresholds for various change of direction angles in basketball players according to gender and analyse the relationships between CODD and execution time in speed tests. One hundred and thirty basketball players (46% female; age: 23.7 ± 5.29 years; height: 189.1 ± 11.1 cm; body mass: 84.3 ± 15.7 kg) undertook 10-m linear and change of direction speed test at 45º, 90º and 180º. A k-means cluster analysis was conducted to standardise CODD thresholds and a one-way analysis of variance to identify the differences between clusters. The results revealed angulation-specific CODD thresholds, ranging from 3% to 8%, 17% to 25% and 43% to 51% for 45º, 90º and 180º cutting angles, respectively for the pooled sample. Furthermore, differences inter-clusters (p < 0.05) were observed for execution time at all cutting angles for both genders. Therefore, strength and conditioning coaches are encouraged to assess CODD as a highly valid variable for evaluating change of direction performance and to use current CODD thresholds to tailor training programmes according to each athlete's needs.

6.
Rev. esp. quimioter ; 37(2): 176-179, abr. 2024. tab
Artigo em Inglês | IBECS | ID: ibc-231652

RESUMO

Objectives. Our observational, retrospective study aimed to determine the correlation between bacteria isolated from bronchial aspirates of pediatric ICU patients (PICU) with respiratory infections and those obtained from conjunctival swabs of the same patients exhibiting clinical conjunctivitis. Material and methods. Throughout the period from 2015 to 2022, we reviewed all clinically significant bronchial aspirates (≥105 CFU/mL) and positive conjunctival swabs obtained from PICU patients. These records were retrieved from the microbiology database, cross-referencing the data to identify patients who tested positive for both during the same clinical episode. Results. The median age of the patients was 5 months (interquartile range: 1-7). Among the cohort, twenty-one patients exhibited positivity in both bronchial aspirate and conjunctival swab samples, showcasing a microbial match in 85.71% of cases (18 out of 21). The most frequently isolated microorganisms were Haemophilus influenzae (55.6%), followed by Pseudomonas aeruginosa (14.3%), Klebsiella aerogenes (9.5%), and Escherichia coli, Stenotrophomonas maltophilia, and Enterobacter cloacae, each accounting for 4.8% of the isolates. Conclusions. Our study demonstrates a strong concordance between the isolated microorganisms from both samples in patients presenting clear symptoms of clinical conjunctivitis. These findings provide a basis for future prospective studies that may leverage conjunctival swabs as a predictive tool for identifying microorganisms involved in respiratory infections. (AU)


Objetivos. Nuestro estudio observacional y retrospectivo tuvo como objetivo determinar la correlación entre las bacterias aisladas de aspirados bronquiales de pacientes de UCI pediátrica (UCIP) con infecciones respiratorias y las obtenidas de hisopos conjuntivales de los mismos pacientes que presentaban conjuntivitis clínica. Material y métodos. A lo largo del periodo comprendido entre 2015 y 2022, se revisaron todos los aspirados bronquiales clínicamente significativos (≥105 UFC/mL) y los hisopos conjuntivalespositivos obtenidos de pacientes de UCIP. Estos registros se recuperaron de la base de datos de microbiología, cruzando los datos para identificar a los pacientes que dieron positivo en ambos durante el mismo episodio clínico. Resultados. La mediana de edad de los pacientes fue de 5 meses (rango intercuartílico: 1-7). Entre la cohorte, veintiún pacientes presentaron positividad tanto en las muestras de aspirado bronquial como en las de hisopo conjuntival, mostrando una coincidencia microbiana en el 85,71% de los casos (18 de 21). Los microorganismos más frecuentemente aislados fueron Haemophilus influenzae (55,6%), seguido de Pseudomonas aeruginosa (14,3%), Klebsiella aerogenes (9,5%) y Escherichia coli, Stenotrophomonas maltophiliay Enterobacter cloacae, cada uno de los cuales representó el 4,8% de los aislamientos. Conclusiones. Nuestro estudio demuestra una fuerte concordancia entre los microorganismos aislados de ambas muestras en pacientes que presentan síntomas claros de conjuntivitis clínica. Estos hallazgos proporcionan una base para futuros estudios prospectivos que podrían aprovechar los hisopos conjuntivales como herramienta predictiva para identificar microorganismos implicados en infecciones respiratorias. (AU)


Assuntos
Humanos , Lactente , Pré-Escolar , Olho , Brônquios , Unidades de Terapia Intensiva Pediátrica , Infecções Respiratórias , Conjuntivite , Microbiologia , Estudos Retrospectivos
7.
Front Public Health ; 12: 1363015, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38566792

RESUMO

Background: Excessive sedentary time has been negatively associated with several health outcomes, and physical activity alone does not seem to fully counteract these consequences. This panorama emphasizes the essential of sedentary time interruption programs. "The Up Project" seeks to assess the effectiveness of two interventions, one incorporating active breaks led by a professional and the other utilizing a computer application (self-led), of both equivalent duration and intensity. These interventions will be compared with a control group to evaluate their impact on physical activity levels, sedentary time, stress perception, occupational pain, and cardiometabolic risk factors among office workers. Methods: This quasi-experimental study includes 60 desk-based workers from universities and educational institutes in Valparaiso, Chile, assigned to three groups: (a) booster breaks led by professionals, (b) computer prompts that are unled, and (c) a control group. The intervention protocol for both experimental groups will last 12 weeks (only weekdays). The following measurements will be performed at baseline and post-intervention: cardiometabolic risk based on body composition (fat mass, fat-free mass, and bone mass evaluated by DXA), waist circumference, blood pressure, resting heart rate, and handgrip strength. Physical activity and sedentary time will be self-reported and device-based assessed using accelerometry. Questionnaires will be used to determine the perception of stress and occupational pain. Discussion: Governments worldwide are addressing health issues associated with sedentary behavior, particularly concerning individuals highly exposed to it, such as desk-based workers. Despite implementing certain strategies, there remains a noticeable gap in comprehensive research comparing diverse protocols. For instance, studies that contrast the outcomes of interventions led by professionals with those prompted by computers are scarce. This ongoing project is expected to contribute to evidence-based interventions targeting reduced perceived stress levels and enhancing desk-based employees' mental and physical well-being. The implications of these findings could have the capacity to lay the groundwork for future public health initiatives and government-funded programs.


Assuntos
Força da Mão , Local de Trabalho , Humanos , Exercício Físico/fisiologia , Ocupações , Dor
8.
Obes Surg ; 34(6): 2101-2110, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38619771

RESUMO

PURPOSE: The feasibility of early telerehabilitation after bariatric surgery is unknown. The objective of this study was to assess the feasibility and perception of engaging in the online exercise protocol in patients during the first month after bariatric surgery. MATERIAL AND METHODS: A total of 67 patients, enrolled in a telerehabilitation program following bariatric surgery, completed a survey assessing their perception of the intensity, discomfort, and safety during exercise sessions. RESULTS: Forty percent of participants began exercising between 5 and 10 days after surgery. Seventy-one percent of patients did not experience discomfort during the first month of exercise, and those who reported discomfort mainly mentioned dizziness and abdominal pain. No significant differences were found in the presence of discomfort among different types of surgeries performed. There was a significant difference in the presence of discomfort between patients who started exercising before and after 15 days of surgery, with less discomfort reported in the group that started after 15 days. Ninety-eight percent of patients felt safe during online exercise sessions. Most participants perceived the intensity of the sessions as moderate. The most frequently mentioned benefits of exercise were increased energy, mood, and feeling more active. CONCLUSION: Telerehabilitation conducted during the first month after bariatric surgery was feasible and well tolerated by patients, providing a safe alternative for those patients who face difficulties with in-person interventions.


Assuntos
Cirurgia Bariátrica , Terapia por Exercício , Estudos de Viabilidade , Obesidade Mórbida , Telerreabilitação , Humanos , Feminino , Masculino , Cirurgia Bariátrica/reabilitação , Adulto , Pessoa de Meia-Idade , Obesidade Mórbida/cirurgia , Obesidade Mórbida/psicologia , Terapia por Exercício/métodos , Inquéritos e Questionários , Satisfação do Paciente
9.
Neuroradiol J ; : 19714009241247459, 2024 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-38613202

RESUMO

Dilated perivascular spaces (PVSs) are common and easily recognized on imaging. However, rarer giant tumefactive PVSs (GTPVSs) can have unusual multilocular cystic configurations, and are often confused for other pathologic entities, including neoplasms, cystic infarctions, and neuroepithelial cysts. Because GTPVSs are scarcely encountered and even more infrequently operated upon, many radiologists are unaware of the imaging and pathologic features of these lesions. Here, a case of a resected GTPVS is presented, highlighting both its radiologic and histologic characteristics, and discussing how such lesions can be differentiated from their closest mimickers on imaging.

10.
J Travel Med ; 2024 Apr 13.
Artigo em Inglês | MEDLINE | ID: mdl-38613442

RESUMO

We present the case of a 75-year-old patient diagnosed with malaria, a native of Zaragoza, Spain, despite having no travel history to malaria-endemic regions. Following an extensive investigation, transfusion emerged as the most probable mode of transmission.

11.
Cureus ; 16(3): e55963, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38601395

RESUMO

Isolated spinal pachymeningitis is rarely encountered in clinical practice. Narrowing down the specific cause in individual patients is challenging as the possible etiologies are broad, there is substantial overlap in clinical presentation, and obtaining adequate data is complex, often affected by prior empiric treatments, including steroids. Here, we describe a rare patient with spinal pachymeningitis resulting in subacute to chronic progressive lower extremity weakness and eventually paraplegia. We discuss how we obtained the final diagnosis, provide our diagnostic framework, and offer practical advice in evaluating these patients.

12.
Reprod Toxicol ; 126: 108584, 2024 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-38561096

RESUMO

In the domain of medical advancement, nanotechnology plays a pivotal role, especially in the synthesis of biocompatible materials for therapeutic use. Superparamagnetic Iron Oxide Nanoparticles (SPIONs), known for their magnetic properties and low toxicity, stand at the forefront of this innovation. This study explored the reproductive toxicological effects of Sodium Citrate-functionalized SPIONs (Cit_SPIONs) in adult male mice, an area of research that holds significant potential yet remains largely unknown. Our findings reveal that Cit_SPIONs induce notable morphological changes in interstitial cells and the seminiferous epithelium when introduced via intratesticular injection. This observation is critical in understanding the interactions of nanomaterials within reproductive biological systems. A striking feature of this study is the rapid localization of Cit_SPIONs in Leydig cells post-injection, a factor that appears to be closely linked with the observed decrease in steroidogenic activity and testosterone levels. This data suggests a possible application in developing nanostructured therapies targeting androgen-related processes. Over 56 days, these nanoparticles exhibited remarkable biological distribution in testis parenchyma, infiltrating various cells within the tubular and intertubular compartments. While the duration of spermatogenesis remained unchanged, there were many Tunel-positive germ cells, a notable reduction in daily sperm production, and reduced progressive sperm motility in the treated group. These insights not only shed light on the intricate mechanisms of Cit_SPIONs interaction with the male reproductive system but also highlight the potential of nanotechnology in developing advanced biomedical applications.

13.
J Appl Clin Med Phys ; 25(5): e14360, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38648734

RESUMO

PURPOSE: Breast density is a significant risk factor for breast cancer and can impact the sensitivity of screening mammography. Area-based breast density measurements may not provide an accurate representation of the tissue distribution, therefore volumetric breast density (VBD) measurements are preferred. Dual-energy mammography enables volumetric measurements without additional assumptions about breast shape. In this work we evaluated the performance of a dual-energy decomposition technique for determining VBD by applying it to virtual anthropomorphic phantoms. METHODS: The dual-energy decomposition formalism was used to quantify VBD on simulated dual-energy images of anthropomorphic virtual phantoms with known tissue distributions. We simulated 150 phantoms with volumes ranging from 50 to 709 mL and VBD ranging from 15% to 60%. Using these results, we validated a correction for the presence of skin and assessed the method's intrinsic bias and variability. As a proof of concept, the method was applied to 14 sets of clinical dual-energy images, and the resulting breast densities were compared to magnetic resonance imaging (MRI) measurements. RESULTS: Virtual phantom VBD measurements exhibited a strong correlation (Pearson's r > 0.95 $r > 0.95$ ) with nominal values. The proposed skin correction eliminated the variability due to breast size and reduced the bias in VBD to a constant value of -2%. Disagreement between clinical VBD measurements using MRI and dual-energy mammography was under 10%, and the difference in the distributions was statistically non-significant. VBD measurements in both modalities had a moderate correlation (Spearman's ρ $\rho \ $ = 0.68). CONCLUSIONS: Our results in virtual phantoms indicate that the material decomposition method can produce accurate VBD measurements if the presence of a third material (skin) is considered. The results from our proof of concept showed agreement between MRI and dual-energy mammography VBD. Assessment of VBD using dual-energy images could provide complementary information in dual-energy mammography and tomosynthesis examinations.


Assuntos
Densidade da Mama , Neoplasias da Mama , Mamografia , Imagens de Fantasmas , Imagem Radiográfica a Partir de Emissão de Duplo Fóton , Humanos , Mamografia/métodos , Feminino , Neoplasias da Mama/diagnóstico por imagem , Imagem Radiográfica a Partir de Emissão de Duplo Fóton/métodos , Mama/diagnóstico por imagem , Processamento de Imagem Assistida por Computador/métodos , Algoritmos , Imageamento por Ressonância Magnética/métodos
14.
Adv Exp Med Biol ; 3234: 73-88, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38507201

RESUMO

The specific kinetics and thermodynamics of protein-protein interactions underlie the molecular mechanisms of cellular functions; hence the characterization of these interaction parameters is central to the quantitative understanding of physiological and pathological processes. Many methods have been developed to study protein-protein interactions, which differ in various features including the interaction detection principle, the sensitivity, whether the method operates in vivo, in vitro, or in silico, the temperature control, the use of labels, immobilization, the amount of sample required, the number of measurements that can be accomplished simultaneously, or the cost. Bio-Layer Interferometry (BLI) is a label-free biophysical method to measure the kinetics of protein-protein interactions. Label-free interaction assays are a broad family of methods that do not require protein modifications (other than immobilization) or labels such as fusions with fluorescent proteins or transactivating domains or chemical modifications like biotinylation or reaction with radionuclides. Besides BLI, other label-free techniques that are widely used for determining protein-protein interactions include surface plasmon resonance (SPR), thermophoresis, and isothermal titration calorimetry (ITC), among others.


Assuntos
Proteínas , Ressonância de Plasmônio de Superfície , Ligação Proteica , Termodinâmica , Proteínas/química , Interferometria/métodos , Cinética
15.
PeerJ Comput Sci ; 10: e1770, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38435615

RESUMO

Overexploitation of fisheries is a worldwide problem, which is leading to a large loss of diversity, and affects human communities indirectly through the loss of traditional jobs, cultural heritage, etc. To address this issue, governments have started accumulating data on fishing activities, to determine biomass extraction rates, and fisheries status. However, these data are often estimated from small samplings, which can lead to partially inaccurate assessments. Fishing can also benefit of the digitization process that many industries are undergoing. Wholesale fish markets, where vessels disembark, can be the point of contact to retrieve valuable information on biomass extraction rates, and can do so automatically. Fine-grained knowledge about the fish species, quantities, sizes, etc. that are caught can be therefore very valuable to all stakeholders, and particularly decision-makers regarding fisheries conservation, sustainable, and long-term exploitation. In this regard, this article presents a full workflow for fish instance segmentation, species classification, and size estimation from uncalibrated images of fish trays at the fish market, in order to automate information extraction that can be helpful in such scenarios. Our results on fish instance segmentation and species classification show an overall mean average precision (mAP) at 50% intersection-over-union (IoU) of 70.42%, while fish size estimation shows a mean average error (MAE) of only 1.27 cm.

16.
Molecules ; 29(5)2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38474634

RESUMO

The inclusion of protein in the regular human diet is important for the prevention of several chronic diseases. In the search for novel alternative protein sources, plant-based proteins are widely explored from a sustainable and ecological point of view. Duckweed (Lemna minor), also known as water lentil, is an aquatic plant with potential applications for human consumption due to its protein content and carbohydrate contents. Among all the conventional and novel protein extraction methods, the utilization of ultrasound has attracted the attention of scientists because of its effects on improving protein extraction and its functionalities. In this work, a Box-Behnken experimental design was proposed to optimize the alkaline extraction of protein from duckweed. In addition, an exploration of the effects of ultrasound on the morphological, structural, and functional properties of the extracted protein was also addressed. The optimal extraction parameters were a pH of 11.5 and an ultrasound amplitude and processing time of 60% and 20 min, respectively. These process conditions doubled the protein content extracted in comparison to the value from the initial duckweed sample. Furthermore, the application of ultrasound during the extraction of protein generated changes in the FTIR spectra, color, and structure of the duckweed protein, which resulted in improvements in its solubility, emulsifying properties, and foaming capacity.


Assuntos
Araceae , Poluentes Químicos da Água , Humanos , Poluentes Químicos da Água/análise , Água/metabolismo
17.
Dalton Trans ; 53(14): 6423-6435, 2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38506269

RESUMO

Combining the experimental techniques of high-resolution X-ray diffraction, magnetometry, specific heat measurement, and X-ray photoelectron, Raman and dielectric spectroscopy techniques, we have studied the influence of La and Cr doping on the crystal structure and magnetism of the room temperature Aurivillius multiferroic Bi5Ti3FeO15 by investigating the physical properties of (Bi4La)Ti3FeO15 and Bi5Ti3 (Fe0.5Cr0.5)O15. The parent (Bi5Ti3FeO15) and the doped ((Bi4La)Ti3FeO15 and Bi5Ti3(Fe0.5Cr0.5)O15) compounds crystallize in the A21am space group, which is confirmed through our analysis of high-resolution synchrotron X-ray diffraction data obtained on phase-pure polycrystalline powders. We determined the oxidation states of the metal atoms in the studied compounds as Fe3+, Ti4+, Cr3+, and La3+ through the analysis of X-ray photoelectron spectroscopy data. The magnetic susceptibilities of the three compounds are marked by the absence of a long-range ordered ground state, but dominated by superparamagnetic clusters with dominant antiferromagnetic interactions. This signature of short-range magnetism is also seen in specific heat as a low temperature enhancement which is suppressed upon the application of external magnetic fields up to 8 T. Our dielectric spectroscopy experiments showed that the three studied compounds display similar features in the dielectric constant measured as a function of frequency. However, upon doping La at the Bi site, the width of the ferroelectric hysteresis loop increases for (Bi4La)Ti3FeO15 compared to that of the parent compound Bi5Ti3FeO15, and with Cr doping, Bi5Ti3(Fe0.5Cr0.5)O15 becomes a leaky dielectric. The resilience of the Aurivillius crystal structure towards doping of La at the Bi site and Cr at the Fe site is clearly seen in the bulk properties of magnetic susceptibility, specific heat and the average crystal structure. The relevance of changes in the local structure is evident from our Raman spectroscopy and X-ray pair distribution function studies.

18.
J Med Biochem ; 43(1): 133-143, 2024 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-38496020

RESUMO

Background: Establishing reference intervals (RIs) in clinical laboratories is essential, as these can vary due to inter-individual variability as well as the analytical methods used. The purpose of this study was to determine RIs for markers and ratios biochemical in apparently healthy Chilean adults. Methods: A sample of 1,143 data was selected from the Universidad Católica de Temuco, Clinical Laboratory database, La Araucanía Region, Chile, which were analysed by sex. The Tukey's Fences was used to detect outliers and the RIs were established using the non-parametric method.

19.
Rev. esp. quimioter ; 37(1): 88-92, Feb. 2024. tab
Artigo em Inglês | IBECS | ID: ibc-230426

RESUMO

The new automated systems designed for rapid performance of AST have significantly reduced the response time for susceptibility testing of microorganisms causing bacteremia and sepsis. The Accelerate Pheno® system (AAC) is one such system. Our objective for this study was to determine whether the AAC system is capable of providing an accurate susceptibility profile to infer resistance mechanisms in different carbapenemase-producing isolates when compared to the MicroScan WalkAway System (MWS). Disk diffusion method was also performed on all isolates as a reference method. Additionally, we compared the results obtained with the routine AST production system. We selected 19 isolates from the cryobank of the Microbiology department, all of which were carbapenemase-producing gram-negative bacilli. AAC was able to identify and infer the resistance of a total of 10 isolates, with an EA and CA of 84.2% for meropenem and 88.2% and 64.7% for ertapenem EA and CA, respectively. If we consider the disk diffusion technique, the CA was 57.9% and 76.5% for meropenem and ertapenem. However, in the presence of carbapenemases, AAC was not able to provide adequate MICs or infer the resistance mechanisms of the isolates accurately. Further studies with a larger number of isolates, including the new antibiotics ceftolozane/tazobactam and ceftazidime/avibactam, are needed for a more comprehensive comparison. (AU)


Los nuevos sistemas automatizados diseñados para la realización rápida de antibiogramas han reducido significativamente el tiempo de respuesta para las pruebas de susceptibilidad de los microorganismos causantes de bacteriemia y sepsis. El sistema Accelerate Pheno® (AAC) es uno de ellos. Nuestro objetivo para este estudio era determinar si el sistema AAC es capaz de proporcionar un perfil de sensibilidad preciso para inferir mecanismos de resistencia en diferentes aislados productores de carbapenemasas en comparación con el sistema MicroScan WalkAway (MWS). El método de disco difusión fue incluido también en todos los aislados como método de referencia. Además, comparamos los resultados obtenidos con el sistema rutinario de producción de antibiogramas rápidos. Seleccionamos 19 aislados del criobanco del departamento de Microbiología, todos ellos bacilos gramnegativos productores de carbapenemasas. AAC fue capaz de identificar e inferir la resistencia de un total de 10 aislados, con una EA y CA del 84,2% para el meropenem y del 88,2% y 64,7% para la EA y CA del ertapenem, respectivamente. Si consideramos la técnica de disco difusión, la CA fue de un 57.9% y de un 76.5% para meropenem y ertapenem. Sin embargo, en presencia de carbapenemasas, AAC no fue capaz de proporcionar CMIs adecuadas ni de inferir con precisión los mecanismos de resistencia de los aislados. Se necesitan más estudios con un mayor número de aislados incluyendo también los nuevos antibióticos ceftolozano/tazobactam y ceftazidima/avibactam para una comparación más exhaustiva. (AU)


Assuntos
Humanos , Anti-Infecciosos/uso terapêutico , /métodos , Antibacterianos/farmacologia , Resistência a Medicamentos , Resistência Microbiana a Medicamentos , Ertapenem , Bactérias Gram-Negativas , Testes de Sensibilidade Microbiana
20.
mSystems ; 9(3): e0123123, 2024 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-38323815

RESUMO

The ability of many human pathogens to infect requires their ability to adhere to the host surfaces as a first step in the process. Porphyromonas gingivalis, a keystone oral pathogen, uses adhesins to adhere to the surface of the gingival epithelium and other members of the oral microbiome. In a previous study, we identified several proteins potentially linked to virulence whose mRNA levels are regulated by CRISPR-Cas type I-C. Among those, PGN_1547 was highly upregulated in the CRISPR-Cas 3 mutant. PGN_1547 is annotated as a hypothetical protein. Employing homology searching, our data support that PGN_1547 resembles an auto-transporter adhesin of P. gingivalis based on containing the DUF2807 domain. To begin to characterize the function of PGN_1547, we found that a deletion mutant displayed a significant decrease in virulence using a Galleria mellonela model. Furthermore, this mutant was significantly impaired in forming biofilms and attaching to the macrophage-like cell THP-1. Luminex revealed that the PGN_1547 mutant elicited a less robust cytokine and chemokine response from THP-1 cells, and TLR2 predominantly sensed that recombinant PGN_1547. Taken together, these findings broaden our understanding of the toolbox of virulence factors possessed by P. gingivalis. Importantly, PGN_1547, a hypothetical protein, has homologs in another member of the order Bacteroidales whose function is unknown, and our results could shed light on the role of this family of proteins as auto-transport adhesins in this phylogenetic group.IMPORTANCEPeriodontal diseases are among humans' most common infections, and besides their effect on the oral cavity, they have been associated with systemic inflammatory conditions. Among members of the oral microbiome implicated in the development of periodontitis, Porphyromonas gingivalis is considered a keystone pathogen. We have identified a new adhesin that acts as a virulence factor, PGN_1547, which contains the DUF2807 domain, which belongs to the putative auto-transporter adhesin, head GIN domain family. Deletion of this gene lowers the virulence of P. gingivalis and impacts the ability of P. gingivalis to form biofilm and attach to host cells. Furthermore, the broad distribution of these receptors in the order Bacteroidales suggests their importance in colonization by this important group of organisms.


Assuntos
Sistemas CRISPR-Cas , Porphyromonas gingivalis , Humanos , Virulência/genética , Porphyromonas gingivalis/genética , Sistemas CRISPR-Cas/genética , Filogenia , Adesinas Bacterianas/genética , Fatores de Virulência/genética
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