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2.
Molecules ; 29(15)2024 Jul 31.
Artículo en Inglés | MEDLINE | ID: mdl-39125036

RESUMEN

Fomitiporia species have aroused the interest of numerous investigations that reveal their biological activity and medicinal potential. The present investigation shows the antioxidant, anticancer, and immunomodulatory activity of acidic polysaccharides obtained from the fungus Fomitiporia chilensis. The acidic polysaccharides were obtained for acidic precipitation with 2% O-N-cetylpyridinium bromide. Chemical analysis was performed using FT-IR and GC-MS methods. The antioxidant capacity of acidic polysaccharides from F. chilensis was evaluated by scavenging free radicals with an ABTS assay. Macrophage proliferation and cytokine production assays were used to determine the immunomodulatory capacity of the polysaccharides. Anti-tumor and cytotoxicity activity was evaluated with an MTT assay in the U-937, HTC-116, and HGF-1 cell lines. The effect of polysaccharides on the cell cycle of the HCT-116 cell line was determined for flow cytometry. Fourier Transform-infrared characterization revealed characteristic absorption peaks for polysaccharides, whereas the GC-MS analysis detected three peaks corresponding to D-galactose, galacturonic acid, and D-glucose. The secreted TNF-α concentration was increased when the cell was treated with 2 mg mL-1 polysaccharides, whereas the IL-6 concentration was increased with all of the evaluated polysaccharide concentrations. A cell cycle analysis of HTC-116 treated with polysaccharides evidenced that the acidic polysaccharides from F. chilensis induce an increase in the G0/G1 cell cycle phase, increasing the apoptotic cell percentage. Results from a proteomic analysis suggest that some of the molecular mechanisms involved in their antioxidant and cellular detoxifying effects and justify their traditional use in heart diseases. Proteomic data are available through ProteomeXchange under identifier PXD048361. The study on acidic polysaccharides from F. chilensis has unveiled their diverse biological activities, including antioxidant, anticancer, and immunomodulatory effects. These findings underscore the promising therapeutic applications of acidic polysaccharides from F. chilensis, warranting further pharmaceutical and medicinal research exploration.


Asunto(s)
Antineoplásicos , Antioxidantes , Polisacáridos Fúngicos , Humanos , Antioxidantes/farmacología , Antioxidantes/química , Antineoplásicos/farmacología , Antineoplásicos/química , Polisacáridos Fúngicos/farmacología , Polisacáridos Fúngicos/química , Proliferación Celular/efectos de los fármacos , Línea Celular Tumoral , Factores Inmunológicos/farmacología , Factores Inmunológicos/química , Animales , Ratones , Polisacáridos/farmacología , Polisacáridos/química , Polisacáridos/aislamiento & purificación , Células HCT116 , Citocinas/metabolismo , Agentes Inmunomoduladores/farmacología , Agentes Inmunomoduladores/química , Espectroscopía Infrarroja por Transformada de Fourier , Apoptosis/efectos de los fármacos
3.
Gels ; 10(8)2024 Aug 03.
Artículo en Inglés | MEDLINE | ID: mdl-39195043

RESUMEN

Due to the increasing prevalence of articular cartilage diseases and limitations faced by current therapeutic methodologies, there is an unmet need for new materials to replace damaged cartilage. In this work, poly(vinyl alcohol) (PVA) hydrogels were reinforced with different amounts of Nomex® (known for its high mechanical toughness, flexibility, and resilience) and sterilized by gamma irradiation. Samples were studied concerning morphology, chemical structure, thermal behavior, water content, wettability, mechanical properties, and rheological and tribological behavior. Overall, it was found that the incorporation of aramid nanostructures improved the hydrogel's mechanical performance, likely due to the reinforcement's intrinsic strength and hydrogen bonding to PVA chains. Additionally, the sterilization of the materials also led to superior mechanical properties, possibly related to the increased crosslinking density through the hydrogen bonding caused by the irradiation. The water content, wettability, and tribological performance of PVA hydrogels were not compromised by either the reinforcement or the sterilization process. The best-performing composite, containing 1.5% wt. of Nomex®, did not induce cytotoxicity in human chondrocytes. Plugs of this hydrogel were inserted in porcine femoral heads and tested in an anatomical hip simulator. No significant changes were observed in the hydrogel or cartilage, demonstrating the material's potential to be used in cartilage replacement.

4.
Bol. latinoam. Caribe plantas med. aromát ; 23(4): 608-635, jul. 2024. tab, ilus, graf, mapas
Artículo en Inglés | LILACS | ID: biblio-1538071

RESUMEN

Chile has two certified origin olive products: Extra-Virgin Olive Oil (EVOO) from Huasco valley and the Azapa variety table olive from the Azapa valley. However, efficient methodologies are needed to determine the varieties and raw materials involved in the end products. In this study, we assessed the size of alleles from ten microsatellites in 20 EVOOs and in leaves and fruits of 16 olive varieties cultivated in Chile to authenticate their origins. The identification of varieties relied on specific allele sizes derived from microsatellites markers UDO99-011 and DCA18-M found in leaves and fruit mesocarp. While most Chilean single-variety EVOOs matched the variety declared on the label, inconsistencies were observed in single-variety EVOOs containing multiple varieties. Our findings confirm that microsatellites serve as a valuable as diagnostic tools for ensuring the quality control of Geographical Indication certification for Azapa olives and EVOO with Designation of Origin from Huasco.


Chile cuenta con dos productos de oliva de origen certificado: El aceite de oliva virgen extra (AOVE) del valle del Huasco y la aceituna de mesa de la variedad Azapa del valle de Azapa. Sin embargo, se necesitan metodologías eficientes para determinar las variedades y materias primas involucradas en los productos finales. En este estudio, evaluamos el tamaño de los alelos de diez microsatélites en 20 AOVEs y en hojas y frutos de 16 variedades de aceituna cultivadas en Chile para autentificar sus orígenes. La identificación de las variedades se basó en los tamaños alélicos específicos derivados de los marcadores microsatélites UDO99-011 y DCA18-M encontrados en las hojas y el mesocarpio de los frutos. Aunque la mayoría de los AOVEs chilenos monovarietales coincidían con la variedad declarada en la etiqueta, se observaron incoherencias en los AOVEs monovarietales que contenían múltiples variedades. Nuestros hallazgos confirman que los microsatélites sirven como valiosas herramientas de diagnóstico para asegurar el control de calidad de la certificación de Indicación Geográfica para aceitunas de Azapa y AOVE con Denominación de Origen de Huasco.


Asunto(s)
Extractos Vegetales/genética , Repeticiones de Microsatélite , Olea/genética , Aceite de Oliva/química , Geografía , Chile
5.
PLoS Comput Biol ; 20(6): e1012166, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38843155

RESUMEN

Despite advances and social progress, the exclusion of diverse groups in academia, especially science, technology, engineering, and mathematics (STEM) fields, across the US and Europe persists, resulting in the underrepresentation of diverse people in higher education. There is extensive literature about theory, observation, and evidence-based practices that can help create a more equitable, inclusive, and diverse learning environment. In this article, we propose the implementation of a Diversity, Equity, Inclusion, and Justice (DEIJ) journal club as a strategic initiative to foster education and promote action towards making academia a more equitable institution. By creating a space for people to engage with DEIJ theories* and strategize ways to improve their learning environment, we hope to normalize the practice and importance of analyzing academia through an equity lens. Guided by restorative justice principles, we offer 10 recommendations for fostering community cohesion through education and mutual understanding. This approach underscores the importance of appropriate action and self-education in the journey toward a more diverse, equitable, inclusive, and just academic environment. *Authors' note: We understand that "DEIJ" is a multidisciplinary organizational framework that relies on numerous fields of study, including history, sociology, philosophy, and more. We use this term to refer to these different fields of study for brevity purposes.


Asunto(s)
Diversidad Cultural , Justicia Social , Humanos , Publicaciones Periódicas como Asunto , Ingeniería/educación , Ciencia/educación , Matemática/educación , Universidades , Diversidad, Equidad e Inclusión
6.
Sci Rep ; 14(1): 13604, 2024 06 13.
Artículo en Inglés | MEDLINE | ID: mdl-38871769

RESUMEN

Neltuma alba (Algarrobo blanco), Neltuma chilensis (Algarrobo Chileno) and Strombocarpa strombulifera (Fortuna) are some of the few drought resistant trees and shrubs found in small highly fragmented populations, throughout the Atacama Desert. We reconstructed their plastid genomes using de novo assembly of paired-end reads from total genomic DNA. We found that the complete plastid genomes of N. alba and N. chilensis are larger in size compared to species of the Strombocarpa genus. The Strombocarpa species presented slightly more GC content than the Neltuma species. Therefore, we assume that Strombocarpa species have been exposed to stronger natural selection than Neltuma species. We observed high variation values in the number of cpSSRs (chloroplast simple sequence repeats) and repeated elements among Neltuma and Strombocarpa species. The p-distance results showed a low evolutionary divergence within the genus Neltuma, whereas a high evolutionary divergence was observed between Strombocarpa species. The molecular divergence time found in Neltuma and Strombocarpa show that these genera diverged in the late Oligocene. With this study we provide valuable information about tree species that provide important ecosystem services in hostile environments which can be used to determine these species in the geographically isolated communities, and keep the highly fragmented populations genetically healthy.


Asunto(s)
Filogenia , Evolución Molecular , Clima Desértico , Genoma de Plastidios , Variación Genética , Composición de Base
7.
Elife ; 122024 Jun 17.
Artículo en Inglés | MEDLINE | ID: mdl-38884443

RESUMEN

Chitin is an abundant biopolymer and pathogen-associated molecular pattern that stimulates a host innate immune response. Mammals express chitin-binding and chitin-degrading proteins to remove chitin from the body. One of these proteins, Acidic Mammalian Chitinase (AMCase), is an enzyme known for its ability to function under acidic conditions in the stomach but is also active in tissues with more neutral pHs, such as the lung. Here, we used a combination of biochemical, structural, and computational modeling approaches to examine how the mouse homolog (mAMCase) can act in both acidic and neutral environments. We measured kinetic properties of mAMCase activity across a broad pH range, quantifying its unusual dual activity optima at pH 2 and 7. We also solved high-resolution crystal structures of mAMCase in complex with oligomeric GlcNAcn, the building block of chitin, where we identified extensive conformational ligand heterogeneity. Leveraging these data, we conducted molecular dynamics simulations that suggest how a key catalytic residue could be protonated via distinct mechanisms in each of the two environmental pH ranges. These results integrate structural, biochemical, and computational approaches to deliver a more complete understanding of the catalytic mechanism governing mAMCase activity at different pH. Engineering proteins with tunable pH optima may provide new opportunities to develop improved enzyme variants, including AMCase, for therapeutic purposes in chitin degradation.


Asunto(s)
Quitina , Quitinasas , Simulación de Dinámica Molecular , Quitinasas/metabolismo , Quitinasas/química , Animales , Concentración de Iones de Hidrógeno , Ratones , Quitina/metabolismo , Quitina/química , Conformación Proteica , Cristalografía por Rayos X , Unión Proteica , Ligandos , Cinética , Acetilglucosamina/metabolismo , Acetilglucosamina/química , Modelos Moleculares
8.
Nat Prod Res ; : 1-6, 2024 Apr 03.
Artículo en Inglés | MEDLINE | ID: mdl-38567750

RESUMEN

Polysaccharides from wood-rooting fungi have attracted attention due to their broad pharmacological properties. Herein, we report the antitumor and immunomodulatory activities of acid polysaccharides isolated from fungi Gloeosoma mirabile. The polysaccharide extracts displayed significant antiproliferative activity against cancer cell lines (MCF-7, HCT-116, U-937) in a dose-dependent manner and induction of IL-6 in macrophage RAW 264.7. Furthermore, flow cytometry analysis showed that high polysaccharide concentrations induced apoptosis by 83% in HL-60 cells. Based on gas chromatography-mass spectrometry (GC-MS) and Fourier transform infra-red (FT-IR) spectroscopy studies, acidic polysaccharides from G. mirabile were mainly composed of arabinose, α-D-galactopyranose and methyl ß-D-galactopyranoside.

9.
Mar Biotechnol (NY) ; 26(2): 324-337, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38430291

RESUMEN

Seaweed from the genus Ulva (Ulvales, Chlorophyta) has a worldwide distribution and represents a potential biomass source for biotechnological applications. In the present study, we investigated the ulvan polysaccharide-rich fraction (UPRF) isolated from two Ulva species (U. rigida and U. pseudorotundata), naturally occurring on the Spanish Mediterranean coast. Chemical characterization of UPRFs was performed in order to explore the polysaccharides' composition. Biological assessments of UPRFs were compared by antioxidant activity and in vitro toxicity tests in the human cell lines: HCT-116 (colon cancer), G-361 (malignant melanoma), U-937 (leukemia), and HaCaT cells (immortalized keratinocytes). Chemical analysis revealed that both UPRFs presented rhamnose as the major relative sugar constituent, followed by glucose in U. rigida and xylose in U. pseudorotundata. Both also presented glucuronic acid, galactose, ribose, and mannose as the remaining monosaccharides. Similar antioxidant activity was obtained, where we observed increased activity in response to increased polysaccharide concentrations. Both UPRFs presented moderate toxicity against HCT-116 cell lines and a selectivity index ≥ 3, suggesting a good potential for use in pharmaceutical products.


Asunto(s)
Antioxidantes , Algas Comestibles , Polisacáridos , Ulva , Ulva/química , Humanos , Polisacáridos/farmacología , Polisacáridos/química , Antioxidantes/farmacología , Antioxidantes/química , Células HCT116 , Línea Celular Tumoral , Antineoplásicos/farmacología , Antineoplásicos/química , Línea Celular , España
10.
Toxicol Mech Methods ; 34(4): 398-407, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38083799

RESUMEN

Liver diseases preceding the occurrence of hepatocellular carcinoma (HCC) play a crucial role in the progression and establishment of HCC, a malignancy ranked as the third deadliest cancer worldwide. Late diagnosis, alongside ineffective treatment, leads patients to a poor survival rate. This scenario argues for seeking novel alternatives for detecting liver alterations preceding the early occurrence of HCC. Experimental studies have reported that ABCC3 protein increases within HCC tumors but not in adjacent tissue. Therefore, we analyzed ABCC3 expression in public databases and investigated the presence of ABCC3 and its isoforms in plasma, urine and its release in extracellular vesicles (EVs) cargo from patients bearing cirrhosis and HCC. The UALCAN and GEPIA databases were used to analyze the expression of ABCC3 in HCC. The results were validated in a case-control study including 41 individuals bearing cirrhosis and HCC, and the levels of ABCC3 in plasma and urine samples, as well as EVs, were analyzed by ELISA and western blot. Our data showed that ABCC3 expression was higher in HCC tissues than in normal tissues and correlated with HCC grade and stage. ABCC3 protein levels were highly increased in both plasma and urine and correlated with liver disease progression and severity. The isoforms MRP3A and MRP3B of ABCC3 were significantly increased in both EVs and plasma/urine of patients bearing HCC. ABCC3 expression gradually increases in HCC tissues, and its protein levels are increased in both plasma and urine of patients with cirrhosis and HCC. MRP3A and MRP3B isoforms have the potential to be prognostic biomarkers of HCC.

11.
bioRxiv ; 2024 Mar 25.
Artículo en Inglés | MEDLINE | ID: mdl-37398339

RESUMEN

Chitin is an abundant biopolymer and pathogen-associated molecular pattern that stimulates a host innate immune response. Mammals express chitin-binding and chitin-degrading proteins to remove chitin from the body. One of these proteins, Acidic Mammalian Chitinase (AMCase), is an enzyme known for its ability to function under acidic conditions in the stomach but is also active in tissues with more neutral pHs, such as the lung. Here, we used a combination of biochemical, structural, and computational modeling approaches to examine how the mouse homolog (mAMCase) can act in both acidic and neutral environments. We measured kinetic properties of mAMCase activity across a broad pH range, quantifying its unusual dual activity optima at pH 2 and 7. We also solved high resolution crystal structures of mAMCase in complex with oligomeric GlcNAcn, the building block of chitin, where we identified extensive conformational ligand heterogeneity. Leveraging these data, we conducted molecular dynamics simulations that suggest how a key catalytic residue could be protonated via distinct mechanisms in each of the two environmental pH ranges. These results integrate structural, biochemical, and computational approaches to deliver a more complete understanding of the catalytic mechanism governing mAMCase activity at different pH. Engineering proteins with tunable pH optima may provide new opportunities to develop improved enzyme variants, including AMCase, for therapeutic purposes in chitin degradation.

12.
Animals (Basel) ; 13(21)2023 Oct 26.
Artículo en Inglés | MEDLINE | ID: mdl-37958080

RESUMEN

The use of functional feeds in aquaculture is currently increasing. This study aimed to assess the combined impact of dietary green microalgae Chlorella fusca and ethanol-inactivated Vibrio proteolyticus DCF12.2 (CVP diet) on thick-lipped grey mullet (Chelon labrosus) juvenile fish. The effects on intestinal microbiota and the transcription of genes related to metabolism, stress, and the immune system were investigated after 90 days of feeding. Additionally, the fish were challenged with Aeromonas hydrophila and polyinosinic-polycytidylic acid (poly I:C) to evaluate the immune response. Microbiota analysis revealed no significant differences in alpha and beta diversity between the anterior and posterior intestinal sections of fish fed the control (CT) and CVP diets. The dominant genera varied between the groups; Pseudomonas and Brevinema were most abundant in the CVP group, whereas Brevinema, Cetobacterium, and Pseudomonas were predominant in the CT group. However, microbial functionality remained unaltered. Gene expression analysis indicated notable changes in hif3α, mhcII, abcb1, mx, and tnfα genes in different fish organs on the CVP diet. In the head kidney, gene expression variations were observed following challenges with A. hydrophila or poly I:C, with higher peak values seen in fish injected with poly I:C. Moreover, c3 mRNA levels were significantly up-regulated in the CVP group 72 h post-A. hydrophila challenge. To conclude, incorporating C. fusca with V. proteolyticus in C. labrosus diet affected the microbial species composition in the intestine while preserving its functionality. In terms of gene expression, the combined diet effectively regulated the transcription of stress and immune-related genes, suggesting potential enhancement of fish resistance against stress and infections.

13.
J Neurooncol ; 165(1): 209-218, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37889443

RESUMEN

PURPOSE: New treatments are needed to improve the overall survival of patients with glioblastoma Metformin is known for anti-tumorigenic effects in cancers, including breast and pancreas cancers. In this study, we assessed the association between metformin use and overall survival in glioblastoma patients. METHODS: We retrospectively studied 241 patients who underwent surgery at diagnosis of glioblastoma between 2014 and 2018. Metformin was used for pre-existing type 2 diabetes mellitus or in the prevention or management of glucocorticoid induced hyperglycemia. Kaplan-Meier curves and log-rank p test were used for univariate analysis. Cox-proportional hazards model was used to generate adjusted hazard ratios for multivariate analysis. RESULTS: Metformin use was associated with longer survival in patients with tumors that had a methylated O6-methylguanine DNA methyltransferase gene (MGMT) promoter (484 days 95% CI: 56-911 vs. 394 days 95% CI: 249-538, Log-Rank test: 6.5, p = 0.01). Cox regression analysis shows that metformin associates with lower risk of death at 2 years in patients with glioblastoma containing a methylated MGMT promoter (aHR = 0.497, 95% CI 0.26-0.93, p = 0.028). CONCLUSION: Our findings suggest a survival benefit with metformin use in patients with glioblastomas having methylation of the MGMT promoter.


Asunto(s)
Neoplasias Encefálicas , Diabetes Mellitus Tipo 2 , Glioblastoma , Metformina , Humanos , Glioblastoma/tratamiento farmacológico , Glioblastoma/genética , Glioblastoma/patología , Metiltransferasas/genética , Estudios Retrospectivos , Metformina/uso terapéutico , Diabetes Mellitus Tipo 2/genética , Metilación de ADN , Metilasas de Modificación del ADN/genética , Neoplasias Encefálicas/tratamiento farmacológico , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/patología , Silenciador del Gen , Enzimas Reparadoras del ADN/genética , Pronóstico , Proteínas Supresoras de Tumor/genética
14.
Molecules ; 28(18)2023 Sep 13.
Artículo en Inglés | MEDLINE | ID: mdl-37764369

RESUMEN

This study reports the use of an inorganic corrosion inhibitor to mitigate dissolved CO2-induced corrosion. Using electrochemical techniques (polarization curves, open circuit potential, polarization resistance, and electrochemical impedance), the effect of adding Nd3+ ions on the corrosion resistance of X52 steel immersed in CO2-saturated brine at 20 °C and 60 °C was evaluated. The polarization curves showed that the Icorr values tend to decrease with increasing Nd3+ ion concentration, up to the optimal inhibition concentration, and that the corrosion potential increases at nobler values. Open circuit potential measurements showed a large increase in potential values immediately after the addition of the Nd3+ ions. Similarly, polarization resistance measurements showed similar trends. It was observed that regardless of temperature, Nd3+ ions can reduce the corrosion rate by more than 97% at doses as low as 0.001 M. Electrochemical impedance measurements confirmed the formation of a protective layer on the steel surface, which caused an increase in the magnitude of the impedance module and phase angle, which indicates an increase in the resistance to charge transfer and capacitive properties of the metallic surface. The characterization of the metallic surface showed that the protective layer was formed by Nd carbonates, whose formation was due to a CO2 capture process.

15.
Microb Ecol ; 86(4): 2802-2818, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37594520

RESUMEN

Coastal areas are often intervened by anthropic activities, which increase the contamination of toxic agents such as heavy metals. This causes adverse morphological effects on benthic microorganisms, such as foraminifera. This group is one of the most susceptible to environmental deterioration, so they can be used as pollution biomarkers by identifying shell abnormalities. Therefore, 28 sediment samples from northern Chile were analyzed, calculating the Abnormality Index-FAI and its spatio-temporal distributions in benthic foraminifera, as well as the minimum and maximum abnormality percentages and their relationship with heavy metal concentrations, using a generalized non-linear model and a principal component analysis. The results indicated a proportion of abnormal shells within the ranges described for polluted areas conditions, revealing environmental stress conditions. This reflected a change in the environmental conditions in the most recent sediments of the bay. The highest FAI values were observed to the southwest of the bay, caused by the local current system. The species Bolivina seminuda, Buliminella elegantissima, and Epistominella exigua presented a greater number of deformities, allowing them to be used as contamination biomarkers. A significant correlation was found between Ti, Mn, Ni, Va, and Ba with decreased chamber sizes, wrong coiling, scars, and number of abnormality types. This suggests the effect of the particular geochemical conditions of the area on the heavy metals that cause toxic effects on foraminifera. These analyses are an efficient tool for identifying the effects of environmental stress before they occur in higher organisms, mitigating the environmental impact on marine biodiversity.


Asunto(s)
Foraminíferos , Metales Pesados , Contaminantes Químicos del Agua , Contaminantes Químicos del Agua/análisis , Sedimentos Geológicos/química , Foraminíferos/química , Monitoreo del Ambiente/métodos , Metales Pesados/toxicidad , Metales Pesados/análisis , Biomarcadores
16.
Front Genet ; 14: 1226052, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37636265

RESUMEN

Chañar (Geoffroea decorticans (Gill., ex Hook. & Arn.) Burkart) has been highly significant for indigenous people in the Atacama Desert for over 3,000 years. Through evolutionary processes, the G. decorticans mitogenome likely underwent changes facilitating its adaptation to the extreme conditions of the Atacama Desert. Here, we compare the mitochondrial genome of G. decorticans with those of other Papilionoideae family species. The complete mitogenome of G. decorticans was sequenced and assembled, making it the first in the genus Geoffroea. The mitogenome contained 383,963 base pairs, consisting of 33 protein coding genes, 21 transfer RNA genes, and 3 ribosomal RNA genes. The Chañar mitogenome is relatively compact, and has two intact genes (sdh4 and nad1) which were not observed in most other species. Additionally, Chañar possessed the highest amount of mitochondrial DNA of plastid origin among angiosperm species. The phylogenetic analysis of the mitogenomes of Chañar and 12 other taxa displayed a high level of consistency in taxonomic classification, when compared to those of the plastid genome. Atp8 was subjected to positive selection, while the ccmFc and rps1 were subjected to neutral selection. This study provides valuable information regarding its ability to survive the extreme environmental conditions of the Atacama Desert.

17.
Neurospine ; 20(2): 478-486, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-37401066

RESUMEN

OBJECTIVE: Lumbar lateral interbody fusion (LLIF) allows placement of large interbody cages while preserving ligamentous structures important for stability. Multiple clinical and biomechanical studies have demonstrated the feasibility of stand-alone LLIF in single-level fusion. We sought to compare the stability of 4-level stand-alone LLIF utilizing wide (26 mm) cages with bilateral pedicle screw and rod fixation. METHODS: Eight human cadaveric specimens of L1-5 were included. Specimens were attached to a universal testing machine (MTS 30/G). Flexion, extension, and lateral bending were attained by applying a 200 N load at a rate of 2 mm/sec. Axial rotation of ± 8° of the specimen was performed at 2°/sec. Three-dimensional specimen motion was recorded using an optical motion-tracking device. Specimens were tested in 4 conditions: (1) intact, (2) bilateral pedicle screws and rods, (3) 26-mm stand-alone LLIF, (4) 26-mm LLIF with bilateral pedicle screws and rods. RESULTS: Compared to the stand-alone LLIF, bilateral pedicle screws and rods had 47% less range of motion in flexion-extension (p < 0.001), 21% less in lateral bending (p < 0.05), and 20% less in axial rotation (p = 0.1). The addition of bilateral posterior instrumentation to the stand-alone LLIF resulted in decreases of all 3 planes of motion: 61% in flexion-extension ( p < 0.001), 57% in lateral bending (p < 0.001), 22% in axial rotation (p = 0.002). CONCLUSION: Despite the biomechanical advantages associated with the lateral approach and 26 mm wide cages, stand-alone LLIF for 4-level fusion is not equivalent to pedicle screws and rods.

18.
World Neurosurg ; 176: 265-271.e2, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-37178910

RESUMEN

OBJECTIVE: The management of external ventricular drains (EVDs) is a critical aspect of patient care in the intensive care setting. However, nurses on the general floor are not commonly exposed to patients with EVD and therefore lack the necessary knowledge and skills to manage and troubleshoot EVDs effectively. The aim of this study was to evaluate the level of knowledge, comfort, and impact of EVD management among nurses on the floor after the implementation of a quality improvement (QI) tool. METHODS: This is a cross-sectional study conducted among registered nurses working on the neurosurgical floors of the Montreal Neurological Hospital. Data were collected using a questionnaire based on the plan-do-study-act model. A survey assessing the level of knowledge and comfort with EVD management was conducted before and after the implementation of the QI tool. RESULTS: Seventy-six nurses completed the questionnaire regarding their knowledge and comfort level in EVD management. Results showed that only 42% of the nurses reported feeling "comfortable" whereas 37% reported feeling "uncomfortable" in caring for patients with an EVD. In addition, only 6.5% reported being "comfortable" in troubleshooting a malfunctioning EVD. However, the level of comfort significantly improved after using the QI project. CONCLUSIONS: The results of this study highlight the need for continued training and education to support the care of patients with EVDs in the ward setting. The implementation of a QI tool can significantly improve nurses' knowledge and comfort level in EVD management, leading to improved patient outcomes and overall quality of care.


Asunto(s)
Atención de Enfermería , Ventriculostomía , Humanos , Ventriculostomía/métodos , Competencia Clínica , Estudios Transversales , Mejoramiento de la Calidad , Drenaje/métodos , Hospitales
19.
Pharmaceuticals (Basel) ; 16(5)2023 Apr 28.
Artículo en Inglés | MEDLINE | ID: mdl-37242444

RESUMEN

One of the main bioactive compounds of interest from the Ulva species is the sulfated polysaccharide ulvan, which has recently attracted attention for its anticancer properties. This study investigated the cytotoxic activity of ulvan polysaccharides obtained from Ulva rigida in the following scenarios: (i) in vitro against healthy and carcinogenic cell lines (1064sk (human fibroblasts), HACAT (immortalized human keratinocytes), U-937 (a human leukemia cell line), G-361 (a human malignant melanoma), and HCT-116 (a colon cancer cell line)) and (ii) in vivo against zebrafish embryos. Ulvan exhibited cytotoxic effects on the three human cancer cell lines tested. However, only HCT-116 demonstrated sufficient sensitivity to this ulvan to make it relevant as a potential anticancer treatment, presenting an LC50 of 0.1 mg mL-1. The in vivo assay on the zebrafish embryos showed a linear relationship between the polysaccharide concentration and growth retardation at 7.8 hpf mL mg-1, with an LC50 of about 5.2 mg mL-1 at 48 hpf. At concentrations near the LC50, toxic effects, such as pericardial edema or chorion lysis, could be found in the experimental larvae. Our in vitro study supports the potential use of polysaccharides extracted from U. rigida as candidates for treating human colon cancer. However, the in vivo assay on zebrafish indicated that the potential use of ulvan as a promising, safe compound should be limited to specific concentrations below 0.001 mg mL-1 since it revealed side effects on the embryonic growth rate and osmolar balance.

20.
Injury ; 2023 Mar 16.
Artículo en Inglés | MEDLINE | ID: mdl-37003872

RESUMEN

INTRODUCTION: Rotatory laxity acceleration still lacks objective classification due to interval grading superposition, resulting in a biased pivot shift grading prior to the Anterior Cruciate Ligament (ACL) reconstruction. However, data analysis might help improve data grading in the operative room. Therefore, we described the improvement of the pivot-shift categorization in Gerdy's acceleration under anesthesia prior to ACL surgery using a support vector machine (SVM) classification, surgeon, and literature reference. METHODS: Seventy-five patients (aged 30.3 ± 10.2 years, and IKDC 52.0 ± 16.5 points) with acute ACL rupture under anesthesia prior to ACL surgery were analyzed. Patients were graded with pivot-shift sign glide (+), clunk (++), and (+++) gross by senior orthopedic surgeons. At the same time, the tri-axial tibial plateau acceleration was measured. Categorical data were statistically described, and the accelerometry and categorical data were associated (α = 5%). A multiclass SVM kernel with the best accuracy trained by orthopedic surgeons and assisted from literature for missing data was compared with experienced surgeons and literature interval grading. The cubic SVM classifier achieved the best grading. RESULTS: The intra-group proportions were different for each grading in the three compared strategies (p < 0.001). The inter-group proportions were different for all comparisons (p < 0.001). There were significant (p < 0.001) associations (Tau: 0.69, -0.28, and -0.50) between the surgeon and SVM, the surgeon and interval grading, and the interval and SVM, respectively. CONCLUSION: The multiclass SVM classifier improves the acceleration categorization of the (+), (++), and (+++) pivot shift sign prior to the ACL surgery in agreement with surgeon criteria.

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