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1.
Proc Natl Acad Sci U S A ; 121(9): e2304643121, 2024 Feb 27.
Artículo en Inglés | MEDLINE | ID: mdl-38377210

RESUMEN

Generating strong rapid adhesion between hydrogels has the potential to advance the capabilities of modern medicine and surgery. Current hydrogel adhesion technologies rely primarily on liquid-based diffusion mechanisms and the formation of covalent bonds, requiring prolonged time to generate adhesion. Here, we present a simple and versatile strategy using dry chitosan polymer films to generate instant adhesion between hydrogel-hydrogel and hydrogel-elastomer surfaces. Using this approach we can achieve extremely high adhesive energies (>3,000 J/m2), which are governed by pH change and non-covalent interactions including H-bonding, Van der Waals forces, and bridging polymer entanglement. Potential examples of biomedical applications are presented, including local tissue cooling, vascular sealing, prevention of surgical adhesions, and prevention of hydrogel dehydration. We expect these findings and the simplicity of this approach to have broad implications for adhesion strategies and hydrogel design.


Asunto(s)
Adhesivos , Polímeros , Humanos , Adherencias Tisulares/prevención & control , Adhesivos/química , Elastómeros , Hidrogeles/química
2.
Ann Surg ; 2024 Jun 28.
Artículo en Inglés | MEDLINE | ID: mdl-38939929

RESUMEN

OBJECTIVE: To propose to our community a common language about extreme liver surgery. BACKGROUND: The lack of a clear definition of extreme liver surgery prevents convincing comparisons of results among centers. METHODS: We used a two-round Delphi methodology to quantify consensus among liver surgery experts. For inclusion in the final recommendations, we established a consensus when the positive responses (agree and totally agree) exceeded 70%. The study steering group summarized and reported the recommendations. In general, a five-point Likert scale with a neutral central value was used, and in a few cases multiple choices. Results are displayed as numbers and percentages. RESULTS: A two-round Delphi study was completed by 38 expert surgeons in complex hepatobiliary surgery. The surgeon´s median age was 58 years old (52-63) and the median years of experience was 25 years (20-31). For the proposed definitions of total vascular occlusion, hepatic flow occlusion and inferior vein occlusion, the degree of agreement was 97%, 81% and 84%, respectively. In situ approach (64%) was the preferred, followed by ante situ (22%) and ex situ (14%). Autologous or cadaveric graft for hepatic artery or hepatic vein repair were the most recommended (89%). The use of veno-venous bypass or portocaval shunt revealed the divergence depending on the case. Overall, 75% of the experts agreed with the proposed definition for extreme liver surgery. CONCLUSION: Obtaining a consensus on the definition of extreme liver surgery is essential to guarantee the correct management of patients with highly complex hepatobiliary oncological disease. The management of candidates for extreme liver surgery involves comprehensive care ranging from adequate patient selection to the appropriate surgical strategy.

3.
Int J Clin Pharmacol Ther ; 61(8): 376, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-37366553

RESUMEN

Cecilia Fernández Del Valle-Laisequilla, Cristian Trejo-Jasso, Juan Carlos Huerta-Cruz, Lina Marcela Barranco-Garduño, Juan Rodríguez-Silverio, Héctor Isaac Rocha-González, Juan Gerardo Reyes-García. Efficacy and safety of a fixed-dose combination of D-norpseudoephedrine, triiodothyronine, atropine, aloin, and diazepam in obese patients. Int J Clin Pharmacol Ther. 2018; 56: 531-538. doi: 10.5414/CP203292. Note from the authors: We realized only now that the affiliation of Cecilia Fernández Del Valle-Laisequilla was indicated in the title page, but due to an unintentional mistake in the final version, the affiliation was not declared in the conflict of interest section, which should read: "Cecilia Fernández Del Valle-Laisequilla is Medical Director of Productos Medix S.A. de C.V."

4.
Microsc Microanal ; 29(3): 938-952, 2023 Jun 09.
Artículo en Inglés | MEDLINE | ID: mdl-37749697

RESUMEN

In this study, a methodology for assessing the thickness of titanium nitride (TiN) coatings by energy dispersive X-ray spectroscopy (EDS) in the scanning electron microscope is explored. A standardless method is applied, where the film thickness (th) is related to the microscope accelerating voltage (V0), the type of substrate and the ratio between the more intense peaks in the EDS spectrum, arising from both the substrate and the coating (afterwards called the I-ratio, IR). Three different substrates covered with TiN were studied, namely, silicon, glass, and stainless steel. Monte Carlo simulations enabled to state an analytic equation, which allows assessing the coating thickness as follows:th=thcr⋅exp[-ßIR1/n]where IR = Iksubstrate/Ikcoating, thcr (critical thickness) is the largest coating thickness, which is assessable at a fixed V0, ß is a multiplication factor, and n is an exponent, where thcr, ß and n are assessable from V0 and substrate type. Interpolation via the equation presented, using reference thicknesses, allowed thickness predictions with around 80% of datapoints differing less than around 2% from the reference value. A procedure for detecting variations as low as 1.0% in coating thickness regarding the nominal thickness is presented.

5.
Pain Manag Nurs ; 24(4): 436-441, 2023 08.
Artículo en Inglés | MEDLINE | ID: mdl-36890094

RESUMEN

BACKGROUND: Somatic symptom disorder is described as excessive thoughts, feelings, or behaviors related to physical symptoms. The presence of somatic symptoms has been associated with depression, alexithymia, and the presence of chronic pain. Individuals with somatic symptom disorder are frequent attenders of primary health care services. AIM: We focused on investigating if the presence of psychological symptoms, alexithymia, or pain could be risk factors for somatic symptoms in a secondary health care service. METHODS: A cross-sectional and observational study. A total of 136 Mexican individuals who regularly attend a secondary health care service were recruited. The Visual Analogue Scale for Pain Assessment, the Symptom Checklist 90, and the Patient Health Questionnaire-15 were applied. RESULTS: Of all the participants, 45.2% showed somatic symptoms. We observed that these individuals more frequently presented with complaints of pain (χ2 = 18.4, p < .001), as well as more severe (t = -4.6, p < .001), and prolonged (χ2 = 4.9, p = 0.02). They also exhibited higher severity in all psychological dimensions assessed (p < .001). Finally, cardiovascular disease (t = 2.52, p = .01), pain intensity (t = 2.94, p = .005), and SCL-90 depression (t = 7.58, p < .001) were associated with somatic symptoms. CONCLUSIONS: In this study, we observed a high frequency of somatic symptoms in outpatients attending secondary health care services. They may be accompanied by comorbid cardiovascular conditions, higher pain intensity, and other mental health-related symptoms, which may aggravate the general clinical picture presented by the patient seeking health care. The presence and severity of somatization should be taken into consideration in the first and second level health care services for an early mental state evaluation and treatment of these outpatients to have a better clinical assessment and health outcome.


Asunto(s)
Dolor Crónico , Síntomas sin Explicación Médica , Humanos , Adulto , Dolor Crónico/complicaciones , Dolor Crónico/epidemiología , Depresión/complicaciones , Depresión/terapia , Pacientes Ambulatorios , Estudios Transversales , Atención a la Salud
6.
Int J Mol Sci ; 24(19)2023 Oct 09.
Artículo en Inglés | MEDLINE | ID: mdl-37834467

RESUMEN

Autophagy is a catabolic process that is essential to the maintenance of homeostasis through the cellular recycling of damaged organelles or misfolded proteins, which sustains energy balance. Additionally, autophagy plays a dual role in modulating the development and progression of cancer and inducing a survival strategy in tumoral cells. Programmed cell death-ligand 1 (PD-L1) modulates the immune response and is responsible for maintaining self-tolerance. Because tumor cells exploit the PD-L1-PD-1 interaction to subvert the immune response, immunotherapy has been developed based on the use of PD-L1-blocking antibodies. Recent evidence has suggested a bidirectional regulation between autophagy and PD-L1 molecule expression in tumor cells. Moreover, the research into the intrinsic properties of PD-L1 has highlighted new functions that are advantageous to tumor cells. The relationship between autophagy and PD-L1 is complex and still not fully understood; its effects can be context-dependent and might differ between tumoral cells. This review refines our understanding of the non-immune intrinsic functions of PD-L1 and its potential influence on autophagy, how these could allow the survival of tumor cells, and what this means for the efficacy of anti-PD-L1 therapeutic strategies.


Asunto(s)
Antígeno B7-H1 , Neoplasias , Humanos , Antígeno B7-H1/metabolismo , Ligandos , Inmunoterapia , Autofagia , Apoptosis
7.
J Stroke Cerebrovasc Dis ; 32(6): 107138, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-37087772

RESUMEN

OBJECTIVE: The purpose of this study was to evaluate the impact of COVID-19 pandemic public health restrictions on our drip and ship mechanical thrombectomy program in Santiago Chile. MATERIALS AND METHODS: This was a retrospective analysis of a prospectively collected database comparing two cohorts, one during a two-year period before COVID-19 and the second during the two years of the pandemic at our metropolitan stroke program. RESULTS: A total of 100 patients were included in the pre COVID-19 cohort (cohort 1) and 121 in the COVID-19 cohort (cohort 2). There was a significant difference between cohorts, with older patients, different occlusion sites and higher door to arterial puncture time during the COVID-19 period. A non-significant trend for worse 90-day outcomes and higher mortality was present in cohort 2. There were no statistical differences in safety treatment parameters. CONCLUSIONS: COVID-19 pandemic has had a measurable impact on our mechanical thrombectomy program. Results showed similarities to other reported Latin American series, where less robust health systems could adapt less efficiently compared to developed countries. After two years of public health restrictions, there were changes in the treatment population characteristics, delay in some internal management metrics and a non-significant trend to worse 90-day outcomes and higher mortality.


Asunto(s)
Isquemia Encefálica , COVID-19 , Accidente Cerebrovascular , Humanos , Síndrome Post Agudo de COVID-19 , Isquemia Encefálica/terapia , Trombectomía/efectos adversos , Trombectomía/métodos , Estudios Retrospectivos , COVID-19/epidemiología , Pandemias , Salud Pública , Resultado del Tratamiento , Accidente Cerebrovascular/diagnóstico , Accidente Cerebrovascular/terapia , Accidente Cerebrovascular/epidemiología
8.
Int J Mol Sci ; 24(5)2023 Feb 27.
Artículo en Inglés | MEDLINE | ID: mdl-36902058

RESUMEN

Whether neuroinflammation leads to dopaminergic nigrostriatal system neurodegeneration is controversial. We addressed this issue by inducing acute neuroinflammation in the substantia nigra (SN) with a single local administration (5 µg/2 µL saline solution) of lipopolysaccharide (LPS). Neuroinflammatory variables were assessed from 48 h to 30 days after the injury by immunostaining for activated microglia (Iba-1 +), neurotoxic A1 astrocytes (C3 + and GFAP +), and active caspase-1. We also evaluated NLRP3 activation and Il-1ß levels by western blot and mitochondrial complex I (CI) activity. Fever and sickness behavior was assessed for 24 h, and motor behavior deficits were followed up until day 30. On this day, we evaluated the cellular senescence marker ß-galactosidase (ß-Gal) in the SN and tyrosine hydroxylase (TH) in the SN and striatum. After LPS injection, Iba-1 (+), C3 (+), and S100A10 (+) cells were maximally present at 48 h and reached basal levels on day 30. NLRP3 activation occurred at 24 h and was followed by a rise of active caspase-1 (+), Il-1ß, and decreased mitochondrial CI activity until 48 h. A significant loss of nigral TH (+) cells and striatal terminals was associated with motor deficits on day 30. The remaining TH (+) cells were ß-Gal (+), suggesting senescent dopaminergic neurons. All the histopathological changes also appeared on the contralateral side. Our results show that unilaterally LPS-induced neuroinflammation can cause bilateral neurodegeneration of the nigrostriatal dopaminergic system and are relevant for understanding Parkinson's disease (PD) neuropathology.


Asunto(s)
Inflamasomas , Trastornos Parkinsonianos , Ratas , Animales , Inflamasomas/metabolismo , Lipopolisacáridos/farmacología , Proteína con Dominio Pirina 3 de la Familia NLR/metabolismo , Enfermedades Neuroinflamatorias , Trastornos Parkinsonianos/metabolismo , Sustancia Negra/metabolismo , Neuronas Dopaminérgicas/metabolismo , Caspasa 1/metabolismo , Dopamina/metabolismo , Microglía/metabolismo
9.
HPB (Oxford) ; 25(10): 1235-1246, 2023 10.
Artículo en Inglés | MEDLINE | ID: mdl-37407399

RESUMEN

BACKGROUND: It is not known if the inflammatory phenomena related to highly accelerated regeneration activate any signaling pathways that are associated with a major stimulus to colorectal liver metastases (CRLM) disease in tourniquet associating liver partition and portal vein ligation for staged hepatectomy (T-ALPPS) compared to two stage hepatectomy (TSH). METHODS: Between January 2012 and April 2018, we prospectively performed biopsies from future liver remnant and deportalized lobe in CRLM patients undergoing T-ALPPS in both stages. Immunohistopathological analysis was performed on the above tissue samples and compared to biopsy samples from patients who underwent TSH for CRLM at our center between September 2000 and August 2011. RESULTS: A total of 42 patients (20 TSH and 22 T-ALPPS) were included. There were no differences in the rates of recurrence, overall survival or any of the factors analyzed relating to tumor progression between stages 1 and 2. Regarding the anti-tumor effect, there was a significant reduction in the number of T-CD8 infiltrates in the second stage of TSH (12.5 vs. 5.5, p = 0.02). CONCLUSION: The results suggest that liver regeneration with T-ALPPS does not induce higher tumor progression or significant immunological changes in the tumor environment when compared to classical TSH.


Asunto(s)
Neoplasias Colorrectales , Neoplasias Hepáticas , Humanos , Hepatectomía/métodos , Vena Porta/cirugía , Vena Porta/patología , Torniquetes , Neoplasias Colorrectales/patología , Hígado/cirugía , Hipertrofia/patología , Hipertrofia/cirugía , Tirotropina , Ligadura , Resultado del Tratamiento
10.
J Mammary Gland Biol Neoplasia ; 27(1): 19-36, 2022 03.
Artículo en Inglés | MEDLINE | ID: mdl-35195812

RESUMEN

Leptin is a cytokine-like hormone that functions as a link between obesity and breast cancer (BC). Leptin treatment induces Epithelial to Mesenchymal Transition (EMT) in BC cell lines. In non-tumoral breast epithelial MCF10A cells, acute leptin treatment induces partial EMT. However, the effect of chronic leptin treatment on EMT in non-tumorigenic breast cells has not been fully explored. This study aimed to evaluate the effect of chronic leptin treatment on the induction of EMT in MCF10A cells. We found that chronic leptin treatment induces a switch from an epithelial to a mesenchymal morphology, partial loss of E-cadherin and gain of vimentin expression. Immunolocalization experiments showed a partial loss of E-cadherin at cell junctions and increased cytoplasmic localization of vimentin in leptin-treated cells. Moreover, chronic leptin treatment increased collective cell migration and invasion. Furthermore, when cultured in non-adherent conditions leptin treated cells exhibited reduced cell aggregation, increased survival, and decreased apoptosis, which correlates with increased FAK and AKT phosphorylation. Finally, bioinformatic analysis in two publicly available RNAseq datasets from normal breast tissue shows that high levels of leptin mRNA correlate positively with the expression of mesenchymal markers, and negatively with epithelial markers. Thus, our results demonstrate that chronic leptin treatment induces EMT in non-tumorigenic MCF10A cells and suggest that high leptin expression in normal breast tissue may induce EMT and contribute to increased risk of breast cancer.


Asunto(s)
Neoplasias de la Mama , Transición Epitelial-Mesenquimal , Neoplasias de la Mama/tratamiento farmacológico , Neoplasias de la Mama/metabolismo , Cadherinas/metabolismo , Línea Celular , Línea Celular Tumoral , Células Epiteliales/metabolismo , Femenino , Humanos , Leptina/metabolismo , Leptina/farmacología , Vimentina/genética , Vimentina/metabolismo , Vimentina/farmacología
12.
Liver Int ; 42(12): 2815-2829, 2022 12.
Artículo en Inglés | MEDLINE | ID: mdl-35533020

RESUMEN

BACKGROUND: While ALPPS triggers a fast liver hypertrophy, it is still unclear which factors matter most to achieve accelerated hypertrophy within a short period of time. The aim of the study was to identify patient-intrinsic factors related to the growth of the future liver remnant (FLR). METHODS: This cohort study is composed of data derived from the International ALPPS Registry from November 2011 and October 2018. We analyse the influence of demographic, tumour type and perioperative data on the growth of the FLR. The volume of the FLR was calculated in millilitre and percentage using computed-tomography (CT) scans before and after stage 1, both according to Vauthey formula. RESULTS: A total of 734 patients were included from 99 centres. The median sFLR at stage 1 and stage 2 was 0.23 (IQR, 0.18-0.28) and 0.39 (IQR: 0.31-0.46), respectively. The variables associated with a lower increase from sFLR1 to sFLR2 were age˃68 years (p = .02), height ˃1.76 m (p ˂ .01), weight ˃83 kg (p ˂ .01), BMI˃28 (p ˂ .01), male gender (p ˂ .01), antihypertensive therapy (p ˂ .01), operation time ˃370 minutes (p ˂ .01) and hospital stay˃14 days (p ˂ .01). The time required to reach sufficient volume for stage 2, male gender accounts 40.3% in group ˂7 days, compared with 50% of female, and female present 15.3% in group ˃14 days compared with 20.6% of male. CONCLUSIONS: Height, weight, FLR size and gender could be the variables that most constantly influence both daily growths, the interstage increase and the standardized FLR before the second stage.


Asunto(s)
Hepatectomía , Neoplasias Hepáticas , Humanos , Masculino , Femenino , Hepatectomía/métodos , Regeneración Hepática , Vena Porta/diagnóstico por imagen , Vena Porta/cirugía , Vena Porta/patología , Estudios de Cohortes , Neoplasias Hepáticas/diagnóstico por imagen , Neoplasias Hepáticas/cirugía , Neoplasias Hepáticas/patología , Ligadura , Hipertrofia/cirugía , Sistema de Registros
13.
Age Ageing ; 51(2)2022 02 02.
Artículo en Inglés | MEDLINE | ID: mdl-35150580

RESUMEN

BACKGROUND: With implementation of stricter blood pressure (BP) treatment targets, potential for excessive BP lowering becomes an important issue, especially in older patients. OBJECTIVES: Assess the magnitude, indicators and detection effort of BP levels below-target-range (BTR-BP) recommended by the European hypertension guidelines in older treated hypertensive patients (130-139/70-79 mmHg). DESIGN: Cross-sectional, retrospective study (Seniors-ENRICA-2 cohort). SETTING: General population. SUBJECTS: 1,329 treated hypertensive patients aged ≥65, assessed with three home casual BP measurements and 24-hour ambulatory BP monitoring (ABPM). METHODS: Based on the European hypertension guidelines and the literature, BTR-BPs were defined as mean BP <130/70, <125/65, <130/70 and <110/55 mmHg, for casual BP, 24-hour BP, daytime BP and nighttime BP, respectively, and hypotension as <110/70, <105/65, <110/70 and <90/55 mmHg, respectively. RESULTS: Participants' mean age was 72 ± 4.4 (50.3%, women). Based on casual BP, 7.2% of patients were in target range (130-139/70-79 mmHg), 44.3% in BTR-BP (<130/70) and 20.8% hypotensive (<110/70). Some 44.9, 54.9 and 22.0% of patients were in BTR-BP for 24-hour BP, daytime BP and nighttime BP, respectively, and 11.0, 21.1 and 5.6%, respectively, were hypotensive. The number of patients needed for ABPM to detect one case of 24-hour-, daytime-, and nighttime-BTR-BP was 3, 2 and 5, respectively, and 10, 5 and 18, respectively, for detecting one hypotensive case. Cardiovascular disease and female sex were associated with both BTR-BP and hypotension, and the number of antihypertensive drugs was only associated with hypotension. CONCLUSIONS: BTR-BP levels were common in older treated patients at home and in everyday life, more frequent than many trials report, and daytime ABPM is highly size-efficient for detecting the low ambulatory BP conditions.


Asunto(s)
Monitoreo Ambulatorio de la Presión Arterial , Hipertensión , Anciano , Presión Sanguínea/fisiología , Estudios Transversales , Femenino , Humanos , Hipertensión/diagnóstico , Hipertensión/tratamiento farmacológico , Hipertensión/epidemiología , Masculino , Estudios Retrospectivos
14.
Int J Clin Pharmacol Ther ; 60(8): 336-345, 2022 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-35770520

RESUMEN

OBJECTIVE: Obesity is the strongest risk factor for type 2 diabetes (T2D). We aimed to explore 7% weight reduction rates of mazindol alone or combined with metformin in non-diabetic obese Mexican subjects who had additional risk factors for T2D. MATERIALS AND METHODS: In this randomized double-blind study, 137 participants received 1 mg mazindol (n = 65) alone or combined with 500 mg metformin (n = 72), twice a day, for 6 months. RESULTS: Mazindol and mazindol-metformin were similarly effective. However, when subjects were subclassified into non-diabetics and prediabetics, according to glycated hemoglobin (HbA1c) - < 5.7% and 5.7 - 6.4%, respectively - and/or fasting plasma glucose (FPG) - < 100 mg/dL and 100 - 125 mg/dL, respectively -, differences were evident. Prediabetics in the mazindol-metformin group had a higher rate of 7% weight reduction (78.4%, n = 37) compared to prediabetics treated with mazindol (48.3%, n = 29). Furthermore, mazindol-metformin treatment induced significant reductions in fasting plasma insulin, HOMA-IR, and HbA1c in prediabetics compared to mazindol. No differences were found in any parameter between non-diabetics treated with mazindol (n = 36) and mazindol-metformin (n = 35). CONCLUSION: Our results highlight the effectiveness of mazindol-metformin to achieve higher rates of 7% weight reduction and to improve the glycemic profile in prediabetic obese subjects, which could be useful to prevent or delay T2D in these subjects.


Asunto(s)
Diabetes Mellitus Tipo 2 , Metformina , Estado Prediabético , Glucemia , Diabetes Mellitus Tipo 2/tratamiento farmacológico , Método Doble Ciego , Hemoglobina Glucada/análisis , Humanos , Hipoglucemiantes/farmacología , Hipoglucemiantes/uso terapéutico , Mazindol , Metformina/farmacología , Metformina/uso terapéutico , Obesidad/complicaciones , Obesidad/tratamiento farmacológico , Estado Prediabético/inducido químicamente , Estado Prediabético/tratamiento farmacológico , Pérdida de Peso
15.
J Stroke Cerebrovasc Dis ; 31(6): 106470, 2022 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-35398625

RESUMEN

OBJECTIVE: To present a rare cause of recurrent posterior embolic strokes originating from a partially thrombosed pseudoaneurysm of a shoulder artery after arthroscopy. MATERIALS AND METHODS: The clinical history, complementary studies and follow-up were reviewed. RESULTS: The patient was successfully embolized and presented no new ischemic episodes at the 3-month follow-up visit. CONCLUSIONS: Shoulder artery pseudoaneurysm should be considered as an unusual source of posterior embolic strokes.


Asunto(s)
Aneurisma Falso , Accidente Cerebrovascular Embólico , Embolia , Embolización Terapéutica , Accidente Cerebrovascular , Aneurisma Falso/complicaciones , Aneurisma Falso/diagnóstico por imagen , Arterias , Infarto Cerebral/complicaciones , Embolia/complicaciones , Embolia/diagnóstico por imagen , Embolización Terapéutica/efectos adversos , Humanos , Accidente Cerebrovascular/diagnóstico por imagen , Accidente Cerebrovascular/etiología , Accidente Cerebrovascular/terapia
16.
Int J Mol Sci ; 23(3)2022 Jan 20.
Artículo en Inglés | MEDLINE | ID: mdl-35163056

RESUMEN

Currently available small diameter vascular grafts (<6 mm) present several long-term limitations, which has prevented their full clinical implementation. Computational modeling and simulation emerge as tools to study and optimize the rational design of small diameter tissue engineered vascular grafts (TEVG). This study aims to model the correlation between mechanical-hemodynamic-biochemical variables on protein adsorption over TEVG and their regenerative potential. To understand mechanical-hemodynamic variables, two-way Fluid-Structure Interaction (FSI) computational models of novel TEVGs were developed in ANSYS Fluent 2019R3® and ANSYS Transient Structural® software. Experimental pulsatile pressure was included as an UDF into the models. TEVG mechanical properties were obtained from tensile strength tests, under the ISO7198:2016, for novel TEVGs. Subsequently, a kinetic model, linked to previously obtained velocity profiles, of the protein-surface interaction between albumin and fibrinogen, and the intima layer of the TEVGs, was implemented in COMSOL Multiphysics 5.3®. TEVG wall properties appear critical to understand flow and protein adsorption under hemodynamic stimuli. In addition, the kinetic model under flow conditions revealed that size and concentration are the main parameters to trigger protein adsorption on TEVGs. The computational models provide a robust platform to study multiparametrically the performance of TEVGs in terms of protein adsorption and their regenerative potential.


Asunto(s)
Prótesis Vascular , Matriz Extracelular/metabolismo , Adsorción , Animales , Simulación por Computador , Hemodinámica , Modelos Anatómicos , Modelos Teóricos , Resistencia a la Tracción
17.
Int J Mol Sci ; 23(18)2022 Sep 14.
Artículo en Inglés | MEDLINE | ID: mdl-36142595

RESUMEN

The gangliosidoses GM2 are a group of pathologies mainly affecting the central nervous system due to the impaired GM2 ganglioside degradation inside the lysosome. Under physiological conditions, GM2 ganglioside is catabolized by the ß-hexosaminidase A in a GM2 activator protein-dependent mechanism. In contrast, uncharged substrates such as globosides and some glycosaminoglycans can be hydrolyzed by the ß-hexosaminidase B. Monogenic mutations on HEXA, HEXB, or GM2A genes arise in the Tay-Sachs (TSD), Sandhoff (SD), and AB variant diseases, respectively. In this work, we validated a CRISPR/Cas9-based gene editing strategy that relies on a Cas9 nickase (nCas9) as a potential approach for treating GM2 gangliosidoses using in vitro models for TSD and SD. The nCas9 contains a mutation in the catalytic RuvC domain but maintains the active HNH domain, which reduces potential off-target effects. Liposomes (LPs)- and novel magnetoliposomes (MLPs)-based vectors were used to deliver the CRISPR/nCas9 system. When LPs were used as a vector, positive outcomes were observed for the ß-hexosaminidase activity, glycosaminoglycans levels, lysosome mass, and oxidative stress. In the case of MLPs, a high cytocompatibility and transfection ratio was observed, with a slight increase in the ß-hexosaminidase activity and significant oxidative stress recovery in both TSD and SD cells. These results show the remarkable potential of CRISPR/nCas9 as a new alternative for treating GM2 gangliosidoses, as well as the superior performance of non-viral vectors in enhancing the potency of this therapeutic approach.


Asunto(s)
Gangliosidosis GM2 , Enfermedad de Tay-Sachs , Desoxirribonucleasa I/metabolismo , Fibroblastos/metabolismo , Proteína Activadora de G (M2) , Gangliósido G(M2)/genética , Gangliósido G(M2)/metabolismo , Gangliosidosis GM2/genética , Gangliosidosis GM2/metabolismo , Gangliosidosis GM2/terapia , Edición Génica , Globósidos/metabolismo , Glicosaminoglicanos/metabolismo , Hexosaminidasa A/metabolismo , Humanos , Lipopolisacáridos/metabolismo , Liposomas/metabolismo , Enfermedad de Tay-Sachs/genética , Enfermedad de Tay-Sachs/metabolismo , Enfermedad de Tay-Sachs/terapia , beta-N-Acetilhexosaminidasas/metabolismo
18.
Molecules ; 27(19)2022 Sep 21.
Artículo en Inglés | MEDLINE | ID: mdl-36234749

RESUMEN

This work studied the feasibility of using a novel microreactor based on torus geometry to carry out a sample pretreatment before its analysis by graphite furnace atomic absorption. The miniaturized retention of total arsenic was performed on the surface of a magnetic sorbent material consisting of 6 mg of magnetite (Fe3O4) confined in a very small space inside (20.1 µL) a polyacrylate device filling an internal lumen (inside space). Using this geometric design, a simulation theoretical study demonstrated a notable improvement in the analyte adsorption process on the solid extractant surface. Compared to single-layer geometries, the torus microreactor geometry brought on flow turbulence within the liquid along the curvatures inside the device channels, improving the efficiency of analyte-extractant contact and therefore leading to a high preconcentration factor. According to this design, the magnetic solid phase was held internally as a surface bed with the use of an 8 mm-diameter cylindric neodymium magnet, allowing the pass of a fixed volume of an arsenic aqueous standard solution. A preconcentration factor of up to 60 was found to reduce the typical "characteristic mass" (as sensitivity parameter) determined by direct measurement from 53.66 pg to 0.88 pg, showing an essential improvement in the arsenic signal sensitivity by absorption atomic spectrometry. This methodology emulates a miniaturized micro-solid-phase extraction system for flow-through water pretreatment samples in chemical analysis before coupling to techniques that employ reduced sample volumes, such as graphite furnace atomic absorption spectroscopy.


Asunto(s)
Arsénico , Grafito , Microextracción en Fase Líquida , Arsénico/análisis , Óxido Ferrosoférrico , Cromatografía de Gases y Espectrometría de Masas , Grafito/química , Microextracción en Fase Líquida/métodos , Fenómenos Magnéticos , Neodimio , Espectrofotometría Atómica/métodos , Agua/química
19.
Can Assoc Radiol J ; 73(3): 557-567, 2022 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-35044276

RESUMEN

Increased intracranial pressure is the most common cause of papilledema. Multiple etiologies such as cerebral edema, hydrocephalus, space occupying lesions, infection, and idiopathic intracranial hypertension among others should be considered. Imaging plays a critical role in the detection of pathologies that can cause papilledema. MRI with contrast and CE-MRV, in particular, are key for the diagnosis of idiopathic intracranial hypertension. This review will focus in common and infrequent causes of papilledema, the role of imaging in patients with papilledema as well as its potential mimickers.


Asunto(s)
Papiledema , Seudotumor Cerebral , Diagnóstico Diferencial , Humanos , Imagen por Resonancia Magnética/efectos adversos , Papiledema/diagnóstico por imagen , Papiledema/etiología , Seudotumor Cerebral/complicaciones , Seudotumor Cerebral/diagnóstico por imagen
20.
Bull Environ Contam Toxicol ; 108(4): 646-651, 2022 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-34807277

RESUMEN

Glyphosate is the most used herbicide in the world. Unfortunately, contamination of water bodies by this herbicide has been reported. A severe concern has been triggered given its detrimental impact on the environment and wildlife. The American horseshoe crab (Limulus polyphemus) is a benthic arthropod that inhabits the Yucatan Peninsula in Southeast Mexico. This study evaluates the glyphosate concentration in 34 recently dead specimens of L. polyphemus from four localities of the Ria Lagartos Biosphere Reserve in Yucatan, Mexico. The analysis was carried out using High-Performance Liquid Chromatography coupled with a Triple Quadrupole Mass Spectrometer. All the samples showed residues of glyphosate in the range from 0.08 to 2.38 ng g-1. These records constitute the first evidence of glyphosate bioaccumulation in this species. Although the scope might be limited, the results demonstrate a potentially prejudicial exposition of the marine biota to glyphosate-based herbicides, given its use in the region.


Asunto(s)
Herbicidas , Cangrejos Herradura , Animales , Glicina/análogos & derivados , Glicina/análisis , Herbicidas/análisis , México , Glifosato
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