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2.
Toxicology ; 508: 153919, 2024 Aug 11.
Artículo en Inglés | MEDLINE | ID: mdl-39137829

RESUMEN

Nephrotoxicity, including electrolytic disorders and acute kidney injury (AKI), limits the clinical dosage and utility of platinated antineoplastics such as cisplatin. Cisplatin nephrotoxicity embodies a tubulopathy involving the medullary S2 and S3 segments of the proximal and the distal tubules. Higher dosage extends damage over the cortical S1 segment and intensifies overall injury. However, the standard diagnosis based on plasma creatinine as well as novel injury biomarkers lacks enough pathophysiological specificity. Further granularity in the detection of renal injury would help understand the implications of individual damage patterns needed for personalized patient handling. In this article, we studied the association of urinary ganglioside GM2 activator protein (GM2AP) with the patterns of tubular damage produced by 5 and 10 mg/kg cisplatin in rats. Our results show that GM2AP appears in the urine only following damage to the cortical segment of the proximal tubule. The information provided by GM2AP is not redundant with but distinct and complementary to that provided by urinary neutrophil gelatinase-associated lipocalin (NGAL). Similarly, treatment with 150 mg/kg/day gentamicin damages the renal cortex and increases GM2AP urinary excretion; whereas renal ischemia, which does not affect the cortex, has no effect on GM2AP. Because of the key role of the cortical proximal tubule in renal function, we contend GM2AP as a potential diagnostic biomarker to stratify AKI patients according to the underlying damage and follow their evolution and prognosis. Prospectively, urinary GM2AP may help grade the severity of platinated antineoplastic nephrotoxicity by forming part of a non-invasive liquid biopsy.

3.
J Environ Manage ; 368: 122104, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-39121620

RESUMEN

A ca. 76% decrease in gross alpha activity levels, measured in surface aerosols collected in the city of Santa Cruz de Tenerife (Spain), has been explained in the present study in connection with the reduction of activities, and eventual closure, of an oil refinery in the city. Gross Alpha in surface aerosols, collected at weekly intervals over a period of 22 years (2001-2022), was used for the analysis. The dynamic behaviour of the gross alpha time series was studied using statistical wavelet, multifractal analysis, empirical decomposition method, multivariate analysis, principal component, and cluster analyses approaches. This was performed to separate the impact of other sources of alpha emitting radionuclides influencing the gross alpha levels at this site. These in-depth analyses revealed a noteworthy shift in the dynamic behaviour of the gross alpha levels following the refinery's closure in 2013. This analysis also attributed fluctuations and trends in the gross alpha levels to factors such as the 2008 global economic crisis and the refinery's gradual reduction of activity leading up to its closure. The mixed-model approach, incorporating multivariate regression and autoregressive integrated moving average methods, explained approximately 84% of the variance of the gross alpha levels. Finally, this work underscored the marked reduction in alpha activity levels following the refinery's closure, alongside the decline of other pollutants (CO, SO2, NO, NO2, Benzene, Toluene and Xylene) linked to the primary industrial activity in the municipality of Santa Cruz de Tenerife.


Asunto(s)
Petróleo , España , Monitoreo del Ambiente , Aerosoles/análisis , Industria del Petróleo y Gas
4.
Chem Biodivers ; : e202401331, 2024 Jun 21.
Artículo en Inglés | MEDLINE | ID: mdl-39031675

RESUMEN

The flowers of Yucca aloifolia ("flor de izote") are considered a millenary food in the Northeastern Highlands of Puebla, Mexico. The present investigation reports on the chemical and biological activities of the hydroalcoholic extract (YAHF) obtained from this edible source. HPLC-MS profiling revealed twenty bioactive phenolic compounds with chlorogenic acid (16.5 mg g-1 DW), quercetin (9.5 mg g-1 FW), and their glycosides (rutin and quercitrin), as well as caffeic acid (8.4 mg g-1 DW) and ferulic acid (7.9 mg g-1 DW) as major compounds dissolved in YAHF. Six metabolites had potent anti-lipase (IC50<100 µg mL-1) and anti-ornithine decarboxylase activity (IC50<100 µg mL-1), whereas thirteen exerted strong anti-alpha-glucosidase properties (IC50<100 µg mL-1). The evaluation of YAHF in mice subjected to standard oral glucose tolerance tests and prolonged administration of hypercaloric/atherogenic diet (30 days), unraveled their ability to improve glucose and lipid profiles. YAHF and six phenolic compounds significantly reduced DLD-1 cell viability (IC50, 117.9 µg mL-1) and avoided polyamine accumulation linked to anti-ornithine decarboxylase activity. YAHF and its twenty constituents exerted low toxicity in probiotics (>1000 µg mL-1) and 3T3 fibroblasts (>2.5 mg-mL-1), sustaining their safeness for human consumption.

5.
Small ; : e2402940, 2024 Jul 14.
Artículo en Inglés | MEDLINE | ID: mdl-39004867

RESUMEN

Iron oxide nanoparticles (IONPs) are widely used for biomedical applications due to their unique magnetic properties and biocompatibility. However, the controlled synthesis of IONPs with tunable particle sizes and crystallite/grain sizes to achieve desired magnetic functionalities across single-domain and multi-domain size ranges remains an important challenge. Here, a facile synthetic method is used to produce iron oxide nanospheres (IONSs) with controllable size and crystallinity for magnetic tunability. First, highly crystalline Fe3O4 IONSs (crystallite sizes above 24 nm) having an average diameter of 50 to 400 nm are synthesized with enhanced ferrimagnetic properties. The magnetic properties of these highly crystalline IONSs are comparable to those of their nanocube counterparts, which typically possess superior magnetic properties. Second, the crystallite size can be widely tuned from 37 to 10 nm while maintaining the overall particle diameter, thereby allowing precise manipulation from the ferrimagnetic to the superparamagnetic state. In addition, demonstrations of reaction scale-up and the proposed growth mechanism of the IONSs are presented. This study highlights the pivotal role of crystal size in controlling the magnetic properties of IONSs and offers a viable means to produce IONSs with magnetic properties desirable for wider applications in sensors, electronics, energy, environmental remediation, and biomedicine.

6.
J Pers Med ; 14(7)2024 Jun 27.
Artículo en Inglés | MEDLINE | ID: mdl-39063946

RESUMEN

Serum neurofilament light chain (sNfL) levels have been proposed as a biomarker of the clinical activity, disability progression, and response to treatment of people with multiple sclerosis (PwMS); however, questions remain about its implementation in clinical practice. Ocrelizumab (OCR) has proven effective in improving clinical and radiological outcomes and reducing sNfL levels. This real-life study followed the sNfL levels of 30 PwMS treated for 12 months with OCR and evaluated the usefulness of this biomarker for their short-term prognosis, considering expanded disability status scale (EDSS), annualized relapse rate (ARR), radiological activity, and NEDA-3 values. OCR reduced ARR in 83% of PwMS and radiological activity in 80%. EDSS was maintained, while NEDA-3 was achieved in 70% at 12 months. OCR produced an early reduction in sNfL levels (at 3 months). At baseline, greater MRI-evaluated radiological activity was associated with higher sNfL levels. sNfL levels over the first 12 months of treatment did not predict a suboptimal response or sustained control of the disease. Longer-term studies are needed to explore the predictive usefulness of sNfL levels in PwMS treated with high-efficacy drugs.

7.
Biomed Pharmacother ; 178: 117152, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-39047420

RESUMEN

Acute kidney injury (AKI) is the most common complication of cardiac surgery. Cardiac surgery-associated AKI (CSA-AKI) is caused by systemic and renal hemodynamic impairment and parenchymal injury. Prophylaxis of CSA-AKI remains an unmet priority, for which preventive strategies based on drug therapies, hydration procedures, and remote ischemic preconditioning (RIPC) have been tested in pre-clinical and clinical studies, with variable success. Contradicting reports and scarce or insufficiently pondered information have blurred conclusions. Therefore, with an aim to contribute to consolidating the available information, we carried out a wide scope, pan-comparative meta-analysis including the accessible information about the most relevant nephroprotective approaches assayed. After a thorough examination of 1892 documents retrieved from PubMed and Web of Science, 150 studies were used for the meta-analysis. Individual odds ratios of efficacy at reducing AKI incidence, need for dialysis, and plasma creatinine elevation were obtained for each alleged protectant. Also, the combined class effect of drug families and protective strategies was also meta-analyzed. Our results show that no drug family or procedure affords substantial protection against CSA-AKI. Only, a mild but significant reduction in the incidence of CSA-AKI by preemptive treatment with dopaminergic and adrenergic drugs, vasodilators, and the RIPC technique. The integrated analysis suggests that single-drug approaches are unlikely to cope with the variety of individual pathophysiological scenarios potentially underlying CSA-AKI. Accordingly, a theragnostic approach involving the etiopathological diagnosis of kidney frailty is necessary to guide research towards the development of pharmacological combinations concomitantly and effectively addressing the key mechanisms of CSA-AKI.


Asunto(s)
Lesión Renal Aguda , Procedimientos Quirúrgicos Cardíacos , Lesión Renal Aguda/prevención & control , Lesión Renal Aguda/etiología , Humanos , Procedimientos Quirúrgicos Cardíacos/efectos adversos , Precondicionamiento Isquémico/métodos , Resultado del Tratamiento
8.
Foods ; 13(12)2024 Jun 19.
Artículo en Inglés | MEDLINE | ID: mdl-38928880

RESUMEN

Fruits and vegetables make up a significant section of the food supply chain and are essential for optimum health and nutrition worldwide [...].

10.
Patient Prefer Adherence ; 18: 1163-1171, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38863945

RESUMEN

Purpose: Shared decision-making is critical in multiple sclerosis (MS) due to the uncertainty of the disease trajectory over time and the large number of treatment options with differing efficacy, safety and administration characteristics. The aim of this study was to assess patients' decisional conflict regarding the choice of a disease-modifying therapy and its associated factors in patients with mid-stage relapsing-remitting multiple sclerosis (RRMS). Methods: A multicenter, non-interventional study was conducted. Adult patients with a diagnosis of RRMS (2017 revised McDonald criteria) and disease duration of 3 to 8 years were included. The level of uncertainty experienced by a patient when faced with making a treatment choice was assessed using the 4-item Decisional Conflict Scale. A battery of patient-reported and clinician-rated measures was administered to obtain information on symptom severity, illness perception, illness-related uncertainty, regret, MS knowledge, risk taking behavior, preferred role in the decision-making process, cognition, and self-management. Patients were recruited during routine follow-up visits and completed all questionnaires online using electronic tablets at the hospital. A multivariate logistic regression analysis was conducted. Results: A total of 201 patients were studied. Mean age (Standard deviation) was 38.7 (8.4) years and 74.1% were female. Median disease duration (Interquartile range) was 6.0 (4.0-7.0) years. Median EDSS score was 1.0 (0-2.0). Sixty-seven (33.3%) patients reported a decisional conflict. These patients had lower MS knowledge and more illness uncertainty, anxiety, depressive symptoms, fatigue, subjective symptom severity, a threatening illness perception, and poorer quality of life than their counterparts. Lack of decisional conflict was associated with MS knowledge (Odds ratio [OR]=1.195, 95% CI 1.045, 1.383, p=0.013), self-management (OR=1.049, 95% CI 1.013, 1.093, p=0.018), and regret after a healthcare decision (OR=0.860, 95% CI 0.756, 0.973, p=0.018) in the multivariate analysis. Conclusion: Decisional conflict regarding the selection of a disease-modifying therapy was a common phenomenon in patients with mid-stage RRMS. Identifying factors associated with decisional conflict may be useful to implement preventive strategies that help patients better understand their condition and strengthen their self-management resources.

11.
Math Biosci Eng ; 21(4): 5826-5837, 2024 Apr 28.
Artículo en Inglés | MEDLINE | ID: mdl-38872560

RESUMEN

In the present work, both direct and inverse problems are considered for a Fisher-type fractional diffusion equation, which is proposed to describe the phenomenon of cell migration. For the direct problem, a solution is given via the Fourier method and the Laplace transform. On the other hand, we solved the inverse problem from a Bayesian statistical framework using a set of data that are the result of a cell migration experiment on a wound closure assay. We estimated the parameters of the mathematical model via Markov Chain Monte Carlo methods.


Asunto(s)
Teorema de Bayes , Movimiento Celular , Cadenas de Markov , Modelos Biológicos , Método de Montecarlo , Humanos , Simulación por Computador , Algoritmos , Difusión , Análisis de Fourier , Animales
12.
Acta Physiol (Oxf) ; 240(8): e14181, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38808913

RESUMEN

Surrogate measures of glomerular filtration rate (GFR) continue to serve as pivotal determinants of the incidence, severity, and management of acute kidney injury (AKI), as well as the primary reference point underpinning knowledge of its pathophysiology. However, several clinically important deficits in aspects of renal excretory function during AKI other than GFR decline, including acid-base regulation, electrolyte and water balance, and urinary concentrating capacity, can evade detection when diagnostic criteria are built around purely GFR-based assessments. The use of putative markers of tubular injury to detect "sub-clinical" AKI has been proposed to expand the definition and diagnostic criteria for AKI, but their diagnostic performance is curtailed by ambiguity with respect to their biological meaning and context specificity. Efforts to devise new holistic assessments of overall renal functional compromise in AKI would foster the capacity to better personalize patient care by replacing biomarker threshold-based diagnostic criteria with a shift to assessment of compromise along a pathophysiological continuum. The term AKI refers to a syndrome of sudden renal deterioration, the severity of which is classified by precise diagnostic criteria that have unquestionable utility in patient management as well as blatant limitations. Particularly, the absence of an explicit pathophysiological definition of AKI curtails further scientific development and clinical handling, entrapping the field within its present narrow GFR-based view. A refreshed approach based on a more holistic consideration of renal functional impairment in AKI as the basis for a new diagnostic concept that reaches beyond the boundaries imposed by the current GFR threshold-based classification of AKI, capturing broader aspects of pathogenesis, could enhance AKI prevention strategies and improve AKI patient outcome and prognosis.


Asunto(s)
Lesión Renal Aguda , Tasa de Filtración Glomerular , Lesión Renal Aguda/fisiopatología , Lesión Renal Aguda/metabolismo , Lesión Renal Aguda/diagnóstico , Humanos , Tasa de Filtración Glomerular/fisiología , Riñón/fisiopatología , Riñón/metabolismo , Biomarcadores/metabolismo , Animales
13.
Clin Ther ; 46(6): 509-514, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38762398

RESUMEN

PURPOSE: The pillar for therapeutic decisions in the evolution of pulmonary arterial hypertension (PAH) is the patients' prognostic stratification. METHODS: A retrospective cohort study was conducted in a Spanish real-world setting to assess the clinical improvement of PAH patients treated with selexipag measured as changes in the risk profile. Secondary objectives were to describe their baseline characteristics, initial risk status, and variables used to assess patient survival and adverse events. FINDINGS: Total 42 patients (mean age 52.36 [SD: 15.09] years) were included. All had received initial endothelin receptor antagonist treatment and 95.2% dual therapy with phosphodiesterase-5 inhibitor or riociguat. At 6 to 12 months from baseline, patients risk stratification tripled the percentage of patients with low risk, and a trend towards improved risk stratification (P = 0.122). World Health Organization functional class changed, with more patients in milder classes (P = 0.003), and symptom progression slowed down (P < 0.0001). At 3-years, survival was 85.7% and the estimated median survival time was 2.73 years (SD: 1.351; 95% CI: 2.51-2.95). IMPLICATIONS: Selexipag did not achieve a significant improvement in risk profile, although it did show an excellent survival rate, effectively improved functional class, and delayed symptom progression in real life. Selexipag was well tolerated and showed a favorable safety profile, supporting a clinical benefit for PAH patients.


Asunto(s)
Acetamidas , Humanos , Masculino , Femenino , Persona de Mediana Edad , Estudios Retrospectivos , Acetamidas/uso terapéutico , Acetamidas/efectos adversos , Adulto , España , Anciano , Hipertensión Arterial Pulmonar/tratamiento farmacológico , Hipertensión Arterial Pulmonar/fisiopatología , Pirazinas/uso terapéutico , Pirazinas/efectos adversos , Resultado del Tratamiento , Receptores de Epoprostenol/agonistas , Pirazoles/uso terapéutico , Pirazoles/efectos adversos , Antihipertensivos/uso terapéutico , Antihipertensivos/efectos adversos , Antagonistas de los Receptores de Endotelina/uso terapéutico , Antagonistas de los Receptores de Endotelina/efectos adversos , Pirimidinas/uso terapéutico , Pirimidinas/efectos adversos , Inhibidores de Fosfodiesterasa 5/uso terapéutico , Inhibidores de Fosfodiesterasa 5/efectos adversos , Hipertensión Pulmonar/tratamiento farmacológico , Hipertensión Pulmonar/fisiopatología
14.
Foods ; 13(10)2024 May 07.
Artículo en Inglés | MEDLINE | ID: mdl-38790742

RESUMEN

The objective of this work was to gain insight into the operating conditions that affect the efficiency of ultrasound-assisted extraction (UAE) parameters to achieve the best recovery of bioactive compounds from broccoli leaf and floret byproducts. Therefore, total phenolic content (TPC) and the main sulfur bioactive compounds (sulforaphane (SFN) and glucosinolates (GLSs)) were assayed. Distilled water was used as solvent. For each byproduct type, solid/liquid ratio (1:25 and 2:25 g/mL), temperature (25, 40, and 55 °C), and extraction time (2.5, 5, 7.5, 10, 15, and 20 min) were the studied variables to optimize the UAE process by using a kinetic and a cubic regression model. TPC was 12.5-fold higher in broccoli leaves than in florets, while SFN was from 2.5- to 4.5-fold higher in florets regarding the leaf's extracts obtained from the same plants, their precursors (GLS) being in similar amounts for both plant tissues. The most efficient extraction conditions were at 25 °C, ratio 2:25, and during 15 or 20 min according to the target phytochemical to extract. In conclusion, the type of plant tissue and used ratio significantly influenced the extraction of bioactive compounds, the most efficient UAE parameters being those with lower energy consumption.

15.
Sci Total Environ ; 942: 173637, 2024 Sep 10.
Artículo en Inglés | MEDLINE | ID: mdl-38821287

RESUMEN

The long-term variability of a 22-year dataset of 7Be, 210Pb and gross alpha concentrations in surface aerosols collected in the Canary Islands has been analysed in this study. These "time series" were collected on a weekly basis. Various analytical techniques, including Principal Component Analysis (PCA), K-means clustering, correlation analyses, and back-trajectory were used to determine the variability of the data and assess the statistical importance of the source of the air masses reaching the study area. Monthly and annual variations for the time series were also studied. As expected, 7Be, 210Pb time series showed common variability, while gross alpha concentrations were strongly correlated with average PM10 concentration in air. The fractal properties of the time series were studied to gain a deeper understanding of the underlying structure and dynamics of the data. Multifractal Detrended Fluctuation Analysis (MF-DFA) and Multifractal Detrended Cross-Correlation Analysis (MF-DCCA) techniques were also used to detect and analyse the multifractal characteristics of the 7Be, 210Pb, and gross alpha time series. Multifractality was observed, with values of 0.28, 0.67, and 0.61 for 7Be, 210Pb, and gross alpha, respectively. Long-range correlation was found to be the source of the observed multifractality in the three parameters. Multifractal detrended cross-correlation analysis supports the correlation between 7Be - Alpha, 210Pb - Alpha, and 7Be - 210Pb pairs. The results from this study will help model the transport and destiny of natural radionuclides in the atmosphere at this site. The evolution and interactions between 7Be, 210Pb, and gross alpha, reported herein occurred not just locally but also across extensive temporal domains, leading to the emergence of multifractal behaviour in their concentrations. These long-range behaviours/correlations might result from various factors such as atmospheric circulation patterns, global transport mechanisms, or large-scale environmental processes.

16.
mSphere ; 9(5): e0007324, 2024 May 29.
Artículo en Inglés | MEDLINE | ID: mdl-38666797

RESUMEN

The signs of climate change are undeniable, and the impact of these changes on ecosystem function heavily depends on the response of microbes that underpin the food web. Antarctic ice shelf is a massive mass of floating ice that extends from the continent into the ocean, exerting a profound influence on global carbon cycles. Beneath Antarctic ice shelves, marine ice stores valuable genetic information, where marine microbial communities before the industrial revolution are archived. Here, in this proof-of-concept, by employing a combination of single-cell technologiesand metagenomics, we have been able to sequence frozen microbial DNA (≈300 years old) stored in the marine ice core B15 collected from the Filchnner-Ronne Ice Shelf. Metagenomic data indicated that Proteobacteria and Thaumarchaeota (e.g., Nitrosopumilus spp.), followed by Actinobacteria (e.g., Actinomarinales), were abundant. Remarkably, our data allow us to "travel to the past" and calibrate genomic and genetic evolutionary changes for ecologically relevant microbes and functions, such as Nitrosopumilus spp., preserved in the marine ice (≈300 years old) with those collected recently in seawater under an ice shelf (year 2017). The evolutionary divergence for the ammonia monooxygenase gene amoA involved in chemolithoautotrophy was about 0.88 amino acid and 2.8 nucleotide substitution rate per 100 sites in a century, while the accumulated rate of genomic SNPs was 2,467 per 1 Mb of genome and 100 years. Whether these evolutionary changes remained constant over the last 300 years or accelerated during post-industrial periods remains an open question that will be further elucidated. IMPORTANCE: Several efforts have been undertaken to predict the response of microbes under climate change, mainly based on short-term microcosm experiments under forced conditions. A common concern is that manipulative experiments cannot properly simulate the response of microbes to climate change, which is a long-term evolutionary process. In this proof-of-concept study with a limited sample size, we demonstrate a novel approach yet to be fully explored in science for accessing genetic information from putative past marine microbes preserved under Antarctic ice shelves before the industrial revolution. This potentially allows us estimating evolutionary changes as exemplified in our study. We advocate for gathering a more comprehensive Antarctic marine ice core data sets across various periods and sites. Such a data set would enable the establishment of a robust baseline, facilitating a better assessment of the potential effects of climate change on key genetic signatures of microbes.


Asunto(s)
Bacterias , Cambio Climático , Cubierta de Hielo , Metagenómica , Microbiota , Agua de Mar , Regiones Antárticas , Cubierta de Hielo/microbiología , Microbiota/genética , Metagenómica/métodos , Bacterias/genética , Bacterias/clasificación , Agua de Mar/microbiología , Archaea/genética , Archaea/clasificación , Ecosistema , Análisis de la Célula Individual , Filogenia
17.
Artículo en Inglés | MEDLINE | ID: mdl-38592435

RESUMEN

Colloidal quantum dots/graphene (QD/Gr) nanohybrids have been studied intensively for photodetection in a broadband spectrum including ultraviolet, visible, near-infrared, and shortwave infrared (UV-vis-NIR-SWIR). Since the optoelectronic process in the QD/Gr nanohybrid relies on the photogenerated charge carrier transfer from QDs to graphene, understanding the role of the QD-QD and QD-Gr interfaces is imperative to the QD/Gr nanohybrid photodetection. Herein, a systematic study is carried out to probe the effect of these interfaces on the noise, photoresponse, and specific detectivity in the UV-vis-NIR-SWIR spectrum. Interestingly, the photoresponse has been found to be negligible without a 3-mercaptopropionic acid (MPA) ligand exchange, moderate with a single ligand exchange after all QD layers are deposited on graphene, and maximum if it is performed after each QD layer deposition up to five layers of total QD thickness of 260-280 nm. Furthermore, exposure of graphene to C-band UV (UVC) for a short period of 4-5 min before QD deposition leads to improved photoresponse via removal of polar molecules at the QD/Gr interface. With the combination of the MPA ligand exchange and UVC exposure, optimal optoelectronic properties can be obtained on the PbS QD/Gr nanohybrids with high specific detectivity up to 2.6 × 1011, 1.5 × 1011, 5 × 1010, and 1.9 × 109 Jones at 400, 550, 1000, and 1700 nm, respectively, making the nanohybrids promising for broadband photodetection.

18.
Materials (Basel) ; 17(7)2024 Apr 05.
Artículo en Inglés | MEDLINE | ID: mdl-38612181

RESUMEN

The use of titanium as a biomaterial for the treatment of dental implants has been successful and has become the most viable and common option. However, in the last three decades, new alternatives have emerged, such as polymers that could replace metallic materials. The aim of this research work is to demonstrate the structural effects caused by the fatigue phenomenon and the comparison with polymeric materials that may be biomechanically viable by reducing the stress shielding effect at the bone-implant interface. A numerical simulation was performed using the finite element method. Variables such as Young's modulus, Poisson's coefficient, density, yield strength, ultimate strength, and the S-N curve were included. Prior to the simulation, a representative digital model of both a dental implant and the bone was developed. A maximum load of 550 N was applied, and the analysis was considered linear, homogeneous, and isotropic. The results obtained allowed us to observe the mechanical behavior of the dental implant by means of displacements and von Mises forces. They also show the critical areas where the implant tends to fail due to fatigue. Finally, this type of non-destructive analysis proves to be versatile, avoids experimentation on people and/or animals, and reduces costs, and the iteration is unlimited in evaluating various structural parameters (geometry, materials, properties, etc.).

19.
Front Pharmacol ; 15: 1373258, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38601468

RESUMEN

Accumulating evidence suggests that hyperuricemia is a pathological factor in the development and progression of chronic kidney disease. However, the potential benefit afforded by the control of uric acid (UA) is controversial. Individual studies show discrepant results, and most existing meta-analysis, especially those including the larger number of studies, lack a placebo or control group as they aim to compare efficacy between drugs. On these grounds, we performed a me-ta-analysis restricted to studies including the action of any anti-gout therapies referenced to a control or placebo arm. This approach allows for a clearer association between UA reduction and renal effect. Of the twenty-nine papers included, most used allopurinol and febuxostat and, therefore, solid conclusions could only be obtained for these drugs. Both were very effective in reducing UA, but only allopurinol was able to significantly improve glomerular filtration rate (GFR), although not in a dose-dependent manner. These results raised doubts as to whether it is the hypouricemic effect of anti-gout drugs, or a pleiotropic effect, what provides protection of kidney function. Accordingly, in a correlation study that we next performed between UA reduction and GFR improvement, no association was found, which suggests that additional mechanisms may be involved. Of note, most trials show large inter-individual response variability, probably because they included patients with heterogeneous phenotypes and pathological characteristics, including different stages of CKD and comorbidities. This highlights the need to sub classify the effect of UA-lowering therapies according to the pathological scenario, in order to identify those CKD patients that may benefit most from them. Systematic Review Registration: CRD42022306646 https://www.crd.york.ac.uk/prospero/.

20.
Rev. Finlay ; 14(1)mar. 2024.
Artículo en Español | LILACS-Express | LILACS | ID: biblio-1565157

RESUMEN

Fundamento: Las enfermedades cardiovasculares constituyen la principal causa de muerte y discapacidad en el mundo. Su incidencia y prevalencia ha aumentado durante la última década y representa un tercio de todas las muertes. Objetivo: Determinar la asociación de LDL-C y grados de riesgo cardiovascular en adultos mayores de 40 años en la Unidad de Medicina Familiar # 43 del Instituto Mexicano del Seguro Social. Método: Se realizó una investigación con un diseño de casos y controles durante el 2023, mediante la fórmula de relación caso-control 1:1, (230 sujetos) que reunieron los criterios de selección. La recolección de la información se realizó por medio de una base de datos en Excel, el contraste de variables se realizó con la fórmula de X2. Mediante el programa de SPSS versión 25 de Windows. Resultados: El género femenino fue el de mayor frecuencia, la media de edad fue de 62 años, el colesterol total elevado presentó 109 (94,8) pacientes con alto riesgo cardiovascular, se calculó una RM: 43.279, IC: 95 %, (17.347-107.980), el colesterol LDL presentó un 68 % (59,1) con riesgo cardiovascular y una RM: 1.28, IC: 95% (0.760-2.158), la evaluación de los triglicéridos con cifras elevadas presentó un 50,4 % (58), RM: 0.037, IC 95 % (0.013-0.106). Conclusiones: La edad media de los sujetos fue, 62 años, predominó el sexo femenino, con mayor proporción de casados, el nivel de escolaridad que prevaleció fue la preparatoria, la religión católica tuvo mayor frecuencia y los sujetos de la zona urbana. Las variables de lípidos como el colesterol total y LDL-C presentaron significancia estadística en relación a riesgo cardiovascular.


Foundation: Cardiovascular diseases are the main cause of death and disability in the world. Its incidence and prevalence has increased over the last decade and accounts for a third of all deaths. Objective: Determine the association of LDL-C and degrees of cardiovascular risk in adults over 40 years of age in the Family Medicine Unit # 43 of the Mexican Social Security Institute. Method: An investigation was carried out with a case-control design during 2023, using the 1:1 case-control ratio formula, (230 subjects) who met the selection criteria. Information collection was carried out through an Excel database, the contrast of variables was carried out with the X2 formula. Using the SPSS version 25 Windows program. Results: The female gender was the most frequent, the average age was 62 years, elevated total cholesterol presented 109 (94.8) patients with high cardiovascular risk, an MRI was calculated: 43,279, CI: 95 %, (17,347-107,980), LDL cholesterol presented 68 % (59.1) with cardiovascular risk and an MRI: 1.28, CI: 95 % (0.760-2.158), the evaluation of triglycerides with high figures presented 50.4 % (58), OR: 0.037, 95 % CI (0.013-0.106). Conclusions: The average age of the subjects was 62 years, the female sex predominated, with a greater proportion of married people, the level of schooling that predominated was high school, the catholic religion was more frequent and the subjects were from the urban area. Lipid variables such as total cholesterol and LDL-C presented statistical significance in relation to cardiovascular risk.

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