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1.
Carbohydr Polym ; 339: 122245, 2024 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-38823913

RESUMEN

The high structural anisotropy and colloidal stability of cellulose nanofibrils' enable the creation of self-standing fibrillar hydrogel networks at very low solid contents. Adding methacrylate moieties on the surface of TEMPO oxidized CNFs allows the formation of more robust covalently crosslinked networks by free radical polymerization of acrylic monomers, exploiting the mechanical properties of these networks more efficiently. This technique yields strong and elastic networks but with an undefined network structure. In this work, we use acrylate-capped telechelic polymers derived from the step-growth polymerization of PEG diacrylate and dithiothreitol to crosslink methacrylated TEMPO-oxidized cellulose nanofibrils (MATO CNF). This combination resulted in flexible and strong hydrogels, as observed through rheological studies, compression and tensile loading. The structure and mechanical properties of these hydrogel networks were found to depend on the dimensions of the CNFs and polymer crosslinkers. The structure of the networks and the role of individual components were evaluated with SAXS (Small-Angle X-ray Scattering) and photo-rheology. A thorough understanding of hybrid CNF/polymer networks and how to best exploit the capacity of these networks enable further advancement of cellulose-based materials for applications in packaging, soft robotics, and biomedical engineering.

2.
Cureus ; 16(5): e59660, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38836154

RESUMEN

Mucinous cystic neoplasms (MCNs) are rare tumors primarily observed in the pancreas but occasionally found in other locations such as the retroperitoneum, ovary, liver, and spleen. These neoplasms are histologically classified based on the degree of dysplasia, with some associated with invasive carcinoma. Colorectal surgeons infrequently encounter MCNs. Mesenteric MCNs pose a diagnostic challenge secondary to their atypical location, subtle histology, and lack of specific biochemical markers. In this context, we present a case involving a 68-year-old female who initially presented with an assumed ovarian mass. Subsequent exploration revealed a 12 cm MCN situated in the sigmoid mesentery, a location seldom associated with these tumors. The patient underwent laparotomy with successful resection and recovery. Histopathological analysis confirmed the neoplasm's mucinous epithelium with a complex papillary architecture. Immunohistochemical staining supported the diagnosis, revealing positivity for CK7, SATB2, and CDX2.

3.
Arch. argent. pediatr ; 122(3): e202310130, jun. 2024. tab, graf
Artículo en Inglés, Español | LILACS, BINACIS | ID: biblio-1554608

RESUMEN

Introducción. Durante 2020 y 2021, la circulación de los virus influenza se mantuvo por debajo de lo esperado en todo el mundo. En Argentina, en el año 2022 observamos una circulación ininterrumpida de influenza todo el año. Nuestros objetivos fueron describir los patrones de circulación y las características clínicas de niños internados con influenza. Población y métodos. Estudio retrospectivo, analítico, observacional. Se incluyeron todos los niños internados en un centro pediátrico con detección del virus influenza durante los años 2019-2022. Resultados. Se internaron 138 pacientes en 4 años; en 2019 se observó una tasa del 4,5/1000 egresos hospitalarios mientras que en 2022, fue del 15,1/1000. En 2020 y 2021 no hubo casos. En el 2019 la mayoría de los casos ocurrieron en invierno, la causa de la internación fue la infección respiratoria aguda baja (IRAB) en el 79 % y se detectó influenza A en el 92 % de los casos. En el 2022, la mayoría de los casos ocurrieron en primavera, el 62 % presentó IRAB y en el 56 % se detectó influenza A. Ambos períodos tuvieron similares frecuencias de vacunación y de comorbilidades. Conclusiones. En el 2022 se registraron más internaciones por influenza, lo que podría corresponder a que se realizaron métodos diagnósticos moleculares, que son más sensibles, y se observó un cambio en la estacionalidad con más casos en primavera. En 2019 predominó influenza A en infecciones del tracto respiratorio inferior, mientras que en el 2022 influenza A y B fueron similares, y hubo más formas extrapulmonares.


Introduction. During 2020 and 2021, the circulation of influenza virus remained below expectations worldwide. In Argentina, in 2022, we observed an uninterrupted circulation of influenza all year round. Our objectives were to describe the circulation patterns and clinical characteristics of hospitalized children with influenza. Population and methods. Retrospective, analytical, observational study. All children with influenza virus admitted to a children's hospital during the 2019­2022 period were included. Results. A total of 138 patients were admitted over 4 years; in 2019, the rate of hospital discharges was 4.5/1000, compared to 15.1/1000 in 2022. No cases were recorded in 2020 and 2021. In 2019, most cases were observed in the winter; in 79%, the cause was acute lower respiratory tract infection (ALRTI); influenza A was detected in 92%. In 2022, most cases occurred in the spring; 62% developed ALRTI; and influenza A was detected in 56%. Similar rates of vaccination and comorbidities were observed in both periods. Conclusions. In 2022, more hospitalizations due to influenza were recorded, which may have correlated with the use of more sensitive molecular diagnostic testing and a change in seasonality, with more cases observed in the spring. In 2019, influenza A predominated in lower respiratory tract infections, while in 2022, cases of influenza A and B were similar, with more extra-pulmonary forms.


Asunto(s)
Humanos , Preescolar , Niño , Infecciones del Sistema Respiratorio/epidemiología , Gripe Humana/diagnóstico , Gripe Humana/epidemiología , COVID-19/diagnóstico , COVID-19/epidemiología , Argentina/epidemiología , Estudios Retrospectivos , Pandemias , Hospitalización , Hospitales
4.
Arch. argent. pediatr ; 122(3): e202310204, jun. 2024. tab, gráf
Artículo en Inglés, Español | LILACS, BINACIS | ID: biblio-1554934

RESUMEN

Introducción. El descenso de las coberturas de vacunación fue muy significativo en la última década. Los pediatras son una pieza fundamental para recuperar coberturas y aumentar la confianza en la vacunación. Objetivos. Describir la percepción de los pediatras acerca del conocimiento y prácticas sobre vacunas, e identificar barreras en el acceso. Métodos. Estudio analítico observacional, mediante encuesta en línea. Se incluyeron variables del perfil del profesional, capacitación y barreras en inmunizaciones. Resultados. Participaron 1696 pediatras (tasa de respuesta: 10,7 %), media de 50,4 años. El 78,7 % fueron mujeres. El 78,2 % contaba con ≥10 años de ejercicio profesional. El 78,4 % realizaba atención ambulatoria y el 56,0 % en el subsector privado. El 72,5 % realizó una capacitación en los últimos 2 años. Se manifestaron "capacitados" para transmitir a sus pacientes los beneficios de las vacunas: 97,2 %; objetivos de campañas: 87,7 %; contraindicaciones: 82,4 %; efectos adversos: 78,9 %; recupero de esquemas: 71,2 %; notificación de ESAVI: 59,5 %. La proporción fue estadísticamente superior, en todos los aspectos, en pediatras con ≥10 años de ejercicio y en aquellos con capacitación reciente (p ≤ 0,01). Barreras identificadas en el acceso a la vacunación: falsas contraindicaciones (62,3 %); falta temporaria de vacunas (46,4 %); motivos culturales (41,4 %); horario restringido del vacunatorio (40,6 %). Conclusiones. La percepción del grado de capacitación fue variable según el aspecto de la vacunación. Aquellos con mayor tiempo de ejercicio profesional y con actualización reciente se manifestaron con mayor grado de capacidad. Se identificaron múltiples barreras frecuentes asociadas al acceso en la vacunación.


Introduction. The decline in vaccination coverage has been very significant in the past decade. Pediatriciansplay a key role in catching-up coverage and increasing confidence in vaccination. Objectives. To describe pediatricians' perceptions of vaccine knowledge and practices and to identify barriers to access. Methods. Observational, analytical study using an online survey. Variables related to professional profile, training and barriers to vaccination were included. Results. A total of 1696 pediatricians participated (response rate: 10.7%). Their mean age was 50.4 years; 78.7% were women; 78.2% had ≥ 10 years of experience; 78.4% provided outpatient care and 56.0%, in the private subsector; and 72.5% received training in the past 2 years. Respondents described themselves as "trained" in convey the following aspects to their patients: benefits of vaccines: 97.2%; campaign objectives: 87.7%; contraindications: 82.4%; adverse effects: 78.9%; catchup vaccination: 71.2%; reporting of events supposedly attributable to vaccination or immunization: 59.5%. The proportion was statistically higher in all aspects, among pediatricians with ≥ 10 years of experience and those who received training recently (p ≤ 0.01). The barriers identified in access to vaccination were false contraindications (62.3%), temporary vaccine shortage (46.4%), cultural reasons (41.4%), and restricted vaccination center hours (40.6%). Conclusions. The perception of the level of training varied depending on the vaccination-related aspect. Pediatricians with more years of professional experience and those who received recent updates perceivedthemselves as more trained. Multiple barriers associated with access to vaccination were identified.


Asunto(s)
Humanos , Persona de Mediana Edad , Vacunas , Vacunación , Percepción , Argentina , Encuestas y Cuestionarios , Pediatras
5.
Bioelectron Med ; 10(1): 12, 2024 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-38745334

RESUMEN

Electrical stimulation of spinal neurons has emerged as a valuable tool to enhance rehabilitation after spinal cord injury. In separate parameterizations, it has shown promise for improving voluntary movement, reducing symptoms of autonomic dysreflexia, improving functions mediated by muscles of the pelvic floor (e.g., bowel, bladder, and sexual function), reducing spasms and spasticity, and decreasing neuropathic pain, among others. This diverse set of actions is related both to the density of sensorimotor neural networks in the spinal cord and to the intrinsic ability of electrical stimulation to modulate neural transmission in multiple spinal networks simultaneously. It also suggests that certain spinal stimulation parameterizations may be capable of providing multi-modal therapeutic benefits, which would directly address the complex, multi-faceted rehabilitation goals of people living with spinal cord injury. This review is intended to identify and characterize reports of spinal stimulation-based therapies specifically designed to provide multi-modal benefits and those that report relevant unintended effects of spinal stimulation paradigms parameterized to enhance a single consequence of spinal cord injury.

6.
Ocul Immunol Inflamm ; : 1-7, 2024 May 17.
Artículo en Inglés | MEDLINE | ID: mdl-38759224

RESUMEN

BACKGROUND: To analyze the clinical course and outcomes of autoimmune vs. non-autoimmune surgically induced scleral necrosis (SISN). METHODS: Multicentric, retrospective, comparative cohort study. Eighty-two eyes of 70 patients with SISN were classified according to pathogenic mechanism into autoimmune vs. non-autoimmune. Main outcome measures included necrosis onset, type of surgery, associated systemic disease, visual acuity, and treatment were analysed in patients followed for ≥ 6 months. RESULTS: Forty-six (65.7%) patients were women, and the median age was 66 (range: 24-90) years. Most patients (82.9%) had unilateral disease. The median time between surgery and SISN onset was 58 (1-480) months. Thirty-one (37.8%) eyes were classified as autoimmune, and 51 (62.2%) as non-autoimmune SISN. Autoimmune SISN was associated with a shorter time between the surgical procedure and SISN onset than non-autoimmune cases (median of 26 vs. 60 months, p = 0.024). Also, autoimmune SISN was associated with cataract extraction (93.5% vs. 25.5%, p < 0.001), severe scleral inflammation (58.1% vs. 17.6%, p < 0.001), and higher incidence of ocular complications (67.7% vs. 33.3%, p = 0.002) than non-autoimmune cases. Remission was achieved with medical management alone in 44 (86.3%) eyes from the non-autoimmune and in 27 (87.1%) from the autoimmune group (p = 0.916). Surgical management was required in 11 (13.4%) eyes, including two requiring enucleations due to scleral perforation and phthisis bulbi. CONCLUSIONS: Eyes with autoimmune SISN had a higher rate of cataract surgery, severe scleral inflammation, and ocular complications. Early SISN diagnosis and appropriate management, based on clinical features and pathogenic mechanisms, are critical to avoid sight-threatening complications.

7.
Biochem Pharmacol ; 225: 116266, 2024 May 06.
Artículo en Inglés | MEDLINE | ID: mdl-38710333

RESUMEN

Cancer continues to be a serious threat to human health worldwide. Lung, prostate and triple-negative breast cancers are amongst the most incident and deadliest cancers. Steroidal compounds are one of the most diversified therapeutic classes of compounds and they were proven to be efficient against several types of cancer. The epoxide function has been frequently associated with anticancer activity, particularly the 1,2-epoxide function. For this reason, three 1,2-epoxysteroid derivatives previously synthesised (EP1, EP2 and EP3) and one synthesised for the first time (oxysteride) were evaluated against H1299 (lung), PC3 (prostate) and HCC1806 (triple-negative breast) cancer cell lines. A human non-tumour cell line, MRC-5 (normal lung cell line) was also used. EP2 was the most active compound in all cell lines with IC50 values of 2.50, 3.67 and 1.95 µM, followed by EP3 with IC50 values of 12.65, 15.10 and 14.16 µM in H1299, PC3 and HCC1806 cells, respectively. Additional studies demonstrated that EP2 and EP3 induced cell death by apoptosis at lower doses and apoptosis/necrosis at higher doses, proving that their effects were dose-dependent. Both compounds also exerted their cytotoxicity by ROS production and by inducing double-strand breaks. Furthermore, EP2 and EP3 proved to be much less toxic against a normal lung cell line, MRC5, indicating that both compounds might be selective, and they also demonstrated suitable in silico ADME and toxicity parameters. Finally, none of the compounds induced haemoglobin release. Altogether, these results point out the extreme relevance of both compounds, especially EP2, in the potential treatment of these types of cancer.

8.
FEBS J ; 2024 May 22.
Artículo en Inglés | MEDLINE | ID: mdl-38775144

RESUMEN

Clostridioides (formerly Clostridium) difficile is a leading cause of infectious diarrhea associated with antibiotic therapy. The ability of this anaerobic pathogen to acquire enough iron to proliferate under iron limitation conditions imposed by the host largely determines its pathogenicity. However, since high intracellular iron catalyzes formation of deleterious reactive hydroxyl radicals, iron uptake is tightly regulated at the transcriptional level by the ferric uptake regulator Fur. Several studies relate lacking a functional fur gene in C. difficile cells to higher oxidative stress sensitivity, colonization defect and less toxigenicity, although Fur does not appear to directly regulate either oxidative stress response genes or pathogenesis genes. In this work, we report the functional characterization of C. difficile Fur and describe an additional oxidation sensing Fur-mediated mechanism independent of iron, which affects Fur DNA-binding. Using electrophoretic mobility shift assays, we show that Fur binding to the promoters of fur, feoA and fldX genes, identified as iron and Fur-regulated genes in vivo, is specific and does not require co-regulator metal under reducing conditions. Fur treatment with H2O2 produces dose-dependent soluble high molecular weight species unable to bind to target promoters. Moreover, Fur oligomers are dithiotreitol sensitive, highlighting the importance of some interchain disulfide bond(s) for Fur oligomerization, and hence for activity. Additionally, the physiological electron transport chain NADPH-thioredoxin reductase/thioredoxin from Escherichia coli reduces inactive oligomerized C. difficile Fur that recovers activity. In conjunction with available transcriptomic data, these results suggest a previously underappreciated complexity in the control of some members of the Fur regulon that is based on Fur redox properties and might be fundamental for the adaptive response of C. difficile during infection.

9.
Lab Anim ; : 236772231163211, 2024 May 23.
Artículo en Inglés | MEDLINE | ID: mdl-38779993

RESUMEN

Melatonin (ML) and dexmedetomidine (DM) are used separately as anesthetic premedication or as an anesthetic in humans and laboratory animals. In this study, we aimed to investigate the anesthetic properties of both drugs combined. The anesthetic effects of several combinations of ML (50 and 100 mg/kg) and DM (50 and 100 µg/kg) were evaluated in rats by observing behavioral manifestations and recording the duration and depth of anesthesia. Five anesthetic intervals were established according to the loss and recovery of reflexes. While each individual drug did not induce an appropriate anesthetic effect at the tested doses, ML50 + DM100, ML100 + DM50 and ML100 + DM100 combinations resulted in surgical anesthesia intervals of 60 to 360 min. Together, our results point that the use of ML allows to decrease the dose of DM, reducing the unwanted anesthetic effects of this α2-agonist.

10.
J AAPOS ; : 103937, 2024 May 19.
Artículo en Inglés | MEDLINE | ID: mdl-38768773

RESUMEN

A 14-year-old boy presented after 2 months of vision loss, redness, and pain in the right eye, initially treated as anterior uveitis with topical corticosteroids. He had a 1-year history of T-cell acute lymphoblastic leukemia, which had been in remission for 6 months. On examination, visual acuity in the right eye was light perception, with 4+ anterior chamber cells, pupillary membrane, and an intumescent cataract. Ultrasound biomicroscopy (UBM) revealed a ciliary body mass and capsular bag rupture. After consultation with his oncologist, he received 10 radiotherapy sessions. At 1 month, UBM showed resolution of the mass. After 1 year of remission, the patient underwent pars plana vitrectomy, pupillary membranectomy, and placement of a scleral-fixated intraocular lens. Thirty months after surgery, visual acuity was 20/25. Leukemic infiltration of the ciliary body is a rare manifestation of the disease that is often misdiagnosed as uveitis.

11.
Int J Mol Sci ; 25(9)2024 Apr 24.
Artículo en Inglés | MEDLINE | ID: mdl-38731872

RESUMEN

Numerous studies suggest the involvement of adenosine-5'-triphosphate (ATP) and similar nucleotides in the pathophysiology of asthma. Androgens, such as testosterone (TES), are proposed to alleviate asthma symptoms in young men. ATP and uridine-5'-triphosphate (UTP) relax the airway smooth muscle (ASM) via purinergic P2Y2 and P2Y4 receptors and K+ channel opening. We previously demonstrated that TES increased the expression of voltage-dependent K+ (KV) channels in ASM. This study investigates how TES may potentiate ASM relaxation induced by ATP and UTP. Tracheal tissues treated with or without TES (control group) from young male guinea pigs were used. In organ baths, tracheas exposed to TES (40 nM for 48 h) showed enhanced ATP- and UTP-evoked relaxation. Tetraethylammonium, a K+ channel blocker, annulled this effect. Patch-clamp experiments in tracheal myocytes showed that TES also increased ATP- and UTP-induced K+ currents, and this effect was abolished with flutamide (an androgen receptor antagonist). KV channels were involved in this phenomenon, which was demonstrated by inhibition with 4-aminopyridine. RB2 (an antagonist of almost all P2Y receptors except for P2Y2), as well as N-ethylmaleimide and SQ 22,536 (inhibitors of G proteins and adenylyl cyclase, respectively), attenuated the enhancement of the K+ currents induced by TES. Immunofluorescence and immunohistochemistry studies revealed that TES did not modify the expression of P2Y4 receptors or COX-1 and COX-2, while we have demonstrated that this androgen augmented the expression of KV1.2 and KV1.5 channels in ASM. Thus, TES leads to the upregulation of P2Y4 signaling and KV channels in guinea pig ASM, enhancing ATP and UTP relaxation responses, which likely limits the severity of bronchospasm in young males.


Asunto(s)
Adenosina Trifosfato , Adenilil Ciclasas , Relajación Muscular , Músculo Liso , Testosterona , Tráquea , Uridina Trifosfato , Animales , Uridina Trifosfato/farmacología , Uridina Trifosfato/metabolismo , Cobayas , Relajación Muscular/efectos de los fármacos , Masculino , Adenosina Trifosfato/metabolismo , Tráquea/metabolismo , Tráquea/efectos de los fármacos , Testosterona/farmacología , Testosterona/metabolismo , Adenilil Ciclasas/metabolismo , Músculo Liso/metabolismo , Músculo Liso/efectos de los fármacos , Canales de Potasio con Entrada de Voltaje/metabolismo , Transducción de Señal/efectos de los fármacos , Receptores Purinérgicos P2/metabolismo
12.
bioRxiv ; 2024 May 06.
Artículo en Inglés | MEDLINE | ID: mdl-38766060

RESUMEN

Glioblastoma (GBM) is the most common primary brain tumor in adults with a poor prognosis despite aggressive therapy. A recent, retrospective clinical study found that administering Temozolomide in the morning increased patient overall survival by 6 months compared to evening. Here, we tested the hypothesis that daily host signaling regulates tumor growth and synchronizes circadian rhythms in GBM. We found daily Dexamethasone promoted or suppressed GBM growth depending on time of day of administration and on the clock gene, Bmal1. Blocking circadian signals, like VIP or glucocorticoids, dramatically slowed GBM growth and disease progression. Finally, mouse and human GBM models have intrinsic circadian rhythms in clock gene expression in vitro and in vivo that entrain to the host through glucocorticoid signaling, regardless of tumor type or host immune status. We conclude that GBM entrains to the circadian circuit of the brain, which modulates its growth through clockcontrolled cues, like glucocorticoids.

14.
Artículo en Inglés, Español | MEDLINE | ID: mdl-38697283

RESUMEN

INTRODUCTION AND OBJECTIVES: The multiparametric implantable cardioverter-defibrillator HeartLogic index has proven to be a sensitive and timely predictor of impending heart failure (HF) decompensation. We evaluated the impact of a standardized follow-up protocol implemented by nursing staff and based on remote management of alerts. METHODS: The algorithm was activated in HF patients at 19 Spanish centers. Transmitted data were analyzed remotely, and patients were contacted by telephone if alerts were issued. Clinical actions were implemented remotely or through outpatient visits. The primary endpoint consisted of HF hospitalizations or death. Secondary endpoints were HF outpatient visits. We compared the 12-month periods before and after the adoption of the protocol. RESULTS: We analyzed 392 patients (aged 69±10 years, 76% male, 50% ischemic cardiomyopathy) with implantable cardioverter-defibrillators (20%) or cardiac resynchronization therapy defibrillators (80%). The primary endpoint occurred 151 times in 86 (22%) patients during the 12 months before the adoption of the protocol, and 69 times in 45 (11%) patients (P<.001) during the 12 months after its adoption. The mean number of hospitalizations per patient was 0.39±0.89 pre- and 0.18±0.57 postadoption (P<.001). There were 185 outpatient visits for HF in 96 (24%) patients before adoption and 64 in 48 (12%) patients after adoption (P<.001). The mean number of visits per patient was 0.47±1.11 pre- and 0.16±0.51 postadoption (P<.001). CONCLUSIONS: A standardized follow-up protocol based on remote management of HeartLogic alerts enabled effective remote management of HF patients. After its adoption, we observed a significant reduction in HF hospitalizations and outpatient visits.

15.
Bioresour Bioprocess ; 11(1): 52, 2024 May 20.
Artículo en Inglés | MEDLINE | ID: mdl-38767776

RESUMEN

The transformation of biomasses from agro-industrial waste can significantly impact the production of green chemicals from sustainable resources. Pectin is a biopolymer present in lignocellulosic biomass as Orange Peel Waste (OPW) and has possibilities for making platform compounds such as furfural for sustainable chemistry. In this work, we studied the transformation to furfural of OPW, pectins, and D-galacturonic acid (D-GalA), which is the main component (65 wt%) of pectin. We analyzed pectins with different degrees of esterification (45, 60 and 95 DE) in a one-pot hydrolysis reaction system and studied the differences in depolymerization and dehydration of the carbohydrates. The results show that the production of furfural decreases as the DE value increases. Specifically, low DE values favor the formation of furfural since the decarboxylation reaction is favored over deesterification. Interestingly, the furfural concentration is dependent upon the polysaccharide composition of pentoses and uronic acid. The obtained concentrations of furfural (13 and 14 mmol/L), D-xylose (6.2 and 10 mmol/L), and L-arabinose (2.5 and 2.7 mmol/L) remained the same when the galacturonic acid was fed either as a polymer or a monomer under the same reaction conditions (0.01 M SA, 90 min and 433 K). OPW is proposed as a feedstock in a biorefinery, in which on a per kg OPW dry basis, 90 g of pectin and 15 g of furfural were produced in the most favorable case. We conclude that the co-production of pectin and furfural from OPW is economically feasible.

16.
J Agric Food Chem ; 72(21): 12281-12294, 2024 May 29.
Artículo en Inglés | MEDLINE | ID: mdl-38747520

RESUMEN

This study investigated the effect of AgNPs and AgNO3, at concentrations equivalent, on the production of primary and secondary metabolites on transgenic soybean plants through an NMR-based metabolomics. The plants were cultivated in a germination chamber following three different treatments: T0 (addition of water), T1 (addition of AgNPs), and T2 (addition of AgNO3). Physiological characteristics, anatomical analyses through microscopic structures, and metabolic profile studies were carried out to establish the effect of abiotic stress on these parameters in soybean plants. Analysis of the 1H NMR spectra revealed the presence of amino acids, organic acids, sugars, and polyphenols. The metabolic profiles of plants with AgNP and AgNO3 were qualitatively similar to the metabolic profile of the control group, suggesting that the application of silver does not affect secondary metabolites. From the PCA, it was possible to differentiate the three treatments applied, mainly based on the content of fatty acids, pinitol, choline, and betaine.


Asunto(s)
Glycine max , Espectroscopía de Resonancia Magnética , Metabolómica , Nanopartículas del Metal , Plantas Modificadas Genéticamente , Plata , Glycine max/metabolismo , Glycine max/genética , Glycine max/química , Glycine max/efectos de los fármacos , Glycine max/crecimiento & desarrollo , Plata/metabolismo , Plata/química , Nanopartículas del Metal/química , Espectroscopía de Resonancia Magnética/métodos , Plantas Modificadas Genéticamente/genética , Plantas Modificadas Genéticamente/metabolismo , Plantas Modificadas Genéticamente/química , Aminoácidos/metabolismo , Ácidos Grasos/metabolismo , Ácidos Grasos/química
17.
bioRxiv ; 2024 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-38798329

RESUMEN

In response to environmental stress, chloroplasts generate reactive oxygen species, including singlet oxygen (1O2), which regulates nuclear gene expression (retrograde signaling), chloroplast turnover, and programmed cell death (PCD). Yet, the central signaling mechanisms and downstream responses remain poorly understood. The Arabidopsis thaliana plastid ferrochelatase two (fc2) mutant conditionally accumulates 1O2 and involves Plant U-Box 4 (PUB4), a cytoplasmic E3 ubiquitin ligase, in propagating these signals. To gain insights into 1O2 signaling pathways, we compared transcriptomes of fc2 and fc2 pub4 mutants. The accumulation of 1O2 in fc2 plants broadly repressed genes involved in chloroplast function and photosynthesis, while 1O2 induced genes and transcription factors involved in abiotic and biotic stress, the biosynthesis of jasmonic acid (JA), and Salicylic acid (SA). Elevated JA and SA levels were observed in stressed fc2 plants, but were not responsible for PCD. pub4 reversed the majority of 1O2-induced gene expression in fc2 and reduced the JA content, but maintained elevated levels of SA even in the absence of 1O2 stress. Reducing SA levels in fc2 pub4 restored 1O2 signaling and light sensitivity. Together, this work demonstrates that SA plays a protective role during photo-oxidative stress and that PUB4 mediates 1O2 signaling by modulating its levels.

18.
Nanomedicine ; 58: 102749, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38719107

RESUMEN

New adjuvant strategies are needed to improve protein-based subunit vaccine immunogenicity. We examined the potential to use nanostructure of 6-O-ascorbyl palmitate to formulate ovalbumin (OVA) protein and an oligodeoxynucleotide (CpG-ODN) (OCC). In mice immunized with a single dose, OCC elicited an OVA-specific immune response superior to OVA/CpG-ODN solution (OC). Rheological studies demonstrated OCC's self-assembling viscoelastic properties. Biodistribution studies indicated that OCC prolonged OVA and CpG-ODN retention at injection site and lymph nodes, reducing systemic spread. Flow-cytometry assays demonstrated that OCC promoted OVA and CpG-ODN co-uptake by Ly6ChiCD11bhiCD11c+ monocytes. OCC and OC induced early IFN-γ in lymph nodes, but OCC led to higher concentration. Conversely, mice immunized with OC showed higher serum IFN-γ concentration compared to those immunized with OCC. In mice immunized with OCC, NK1.1+ cells were the IFN-γ major producers, and IFN-γ was essential for OVA-specific IgG2c switching. These findings illustrate how this nanostructure improves vaccine's response.


Asunto(s)
Nanoestructuras , Oligodesoxirribonucleótidos , Ovalbúmina , Vacunas de Subunidad , Animales , Nanoestructuras/química , Vacunas de Subunidad/inmunología , Vacunas de Subunidad/química , Vacunas de Subunidad/farmacocinética , Ratones , Oligodesoxirribonucleótidos/química , Oligodesoxirribonucleótidos/farmacocinética , Ovalbúmina/inmunología , Ovalbúmina/química , Femenino , Ratones Endogámicos C57BL , Adyuvantes Inmunológicos/química , Adyuvantes Inmunológicos/farmacocinética , Interferón gamma/metabolismo , Distribución Tisular , Ácido Ascórbico/análogos & derivados
19.
Sci Rep ; 14(1): 10241, 2024 05 03.
Artículo en Inglés | MEDLINE | ID: mdl-38702365

RESUMEN

Within the bloodstream, monocytes must traverse the microvasculature to prevent leukostasis, which is the entrapment of monocytes within the confines of the microvasculature. Using the model cell line, THP-1, and VCAM-1 coated channels to simulate the microvasculature surface, we demonstrate that monocytes predominantly adopt an amoeboid phenotype, which is characterized by the formation of blebs. As opposed to cortical actin flow in leader blebs, cell movement is correlated with myosin contraction at the cell rear. It was previously documented that cofilin-1 promotes cortical actin turnover at leader bleb necks in melanoma cells. In monocytes, our data suggest that cofilin-1 promotes the local upregulation of myosin contractility through actin cytoskeleton remodeling. In support of this concept, cofilin-1 is found to localize to a single cell edge. Moreover, the widespread upregulation of myosin contractility was found to inhibit migration. Thus, monocytes within the microvasculature may avoid entrapment by adopting an amoeboid mode of migration.


Asunto(s)
Citoesqueleto de Actina , Movimiento Celular , Cofilina 1 , Monocitos , Humanos , Citoesqueleto de Actina/metabolismo , Actinas/metabolismo , Cofilina 1/metabolismo , Monocitos/metabolismo , Miosinas/metabolismo , Células THP-1 , Molécula 1 de Adhesión Celular Vascular/metabolismo
20.
Molecules ; 29(10)2024 May 12.
Artículo en Inglés | MEDLINE | ID: mdl-38792145

RESUMEN

The Cupressaceae family includes species considered to be medicinal. Their essential oil is used for headaches, colds, cough, and bronchitis. Cedar trees like Chamaecyparis lawsoniana (C. lawsoniana) are commonly found in urban areas. We investigated whether C. lawsoniana exerts some of its effects by modifying airway smooth muscle (ASM) contractility. The leaves of C. lawsoniana (363 g) were pulverized mechanically, and extracts were obtained by successive maceration 1:10 (w:w) with methanol/CHCl3. Guinea pig tracheal rings were contracted with KCl, tetraethylammonium (TEA), histamine (HIS), or carbachol (Cch) in organ baths. In the Cch experiments, tissues were pre-incubated with D-600, an antagonist of L-type voltage-dependent Ca2+ channels (L-VDCC) before the addition of C. lawsoniana. Interestingly, at different concentrations, C. lawsoniana diminished the tracheal contractions induced by KCl, TEA, HIS, and Cch. In ASM cells, C. lawsoniana significantly diminished L-type Ca2+ currents. ASM cells stimulated with Cch produced a transient Ca2+ peak followed by a sustained plateau maintained by L-VDCC and store-operated Ca2+ channels (SOCC). C. lawsoniana almost abolished this last response. These results show that C. lawsoniana, and its active metabolite quercetin, relax the ASM by inhibiting the L-VDCC and SOCC; further studies must be performed to obtain the complete set of metabolites of the extract and study at length their pharmacological properties.


Asunto(s)
Calcio , Chamaecyparis , Contracción Muscular , Músculo Liso , Extractos Vegetales , Quercetina , Tráquea , Animales , Cobayas , Músculo Liso/efectos de los fármacos , Músculo Liso/metabolismo , Contracción Muscular/efectos de los fármacos , Quercetina/farmacología , Quercetina/química , Tráquea/efectos de los fármacos , Tráquea/metabolismo , Extractos Vegetales/farmacología , Extractos Vegetales/química , Chamaecyparis/química , Calcio/metabolismo , Masculino , Bloqueadores de los Canales de Calcio/farmacología , Histamina/metabolismo , Canales de Calcio Tipo L/metabolismo , Hojas de la Planta/química
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