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1.
Nature ; 600(7887): 133-137, 2021 12.
Artículo en Inglés | MEDLINE | ID: mdl-34789872

RESUMEN

Coronaviruses have caused three major epidemics since 2003, including the ongoing SARS-CoV-2 pandemic. In each case, the emergence of coronavirus in our species has been associated with zoonotic transmissions from animal reservoirs1,2, underscoring how prone such pathogens are to spill over and adapt to new species. Among the four recognized genera of the family Coronaviridae, human infections reported so far have been limited to alphacoronaviruses and betacoronaviruses3-5. Here we identify porcine deltacoronavirus strains in plasma samples of three Haitian children with acute undifferentiated febrile illness. Genomic and evolutionary analyses reveal that human infections were the result of at least two independent zoonoses of distinct viral lineages that acquired the same mutational signature in the genes encoding Nsp15 and the spike glycoprotein. In particular, structural analysis predicts that one of the changes in the spike S1 subunit, which contains the receptor-binding domain, may affect the flexibility of the protein and its binding to the host cell receptor. Our findings highlight the potential for evolutionary change and adaptation leading to human infections by coronaviruses outside of the previously recognized human-associated coronavirus groups, particularly in settings where there may be close human-animal contact.


Asunto(s)
Infecciones por Coronavirus/epidemiología , Infecciones por Coronavirus/virología , Deltacoronavirus/aislamiento & purificación , Porcinos/virología , Zoonosis Virales/epidemiología , Zoonosis Virales/virología , Secuencia de Aminoácidos , Animales , Teorema de Bayes , Niño , Chlorocebus aethiops , Secuencia Conservada , Infecciones por Coronavirus/sangre , Deltacoronavirus/clasificación , Deltacoronavirus/genética , Deltacoronavirus/patogenicidad , Femenino , Haití/epidemiología , Humanos , Masculino , Modelos Moleculares , Mutación , Filogenia , Células Vero , Zoonosis Virales/sangre
2.
Inorg Chem ; 63(13): 5783-5804, 2024 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-38502532

RESUMEN

In recent years, organometallic complexes have attracted much attention as anticancer therapeutics aiming at overcoming the limitations of platinum drugs that are currently marketed. Still, the development of half-sandwich organometallic cobalt complexes remains scarcely explored. Four new cobalt(III)-cyclopentadienyl complexes containing N,N-heteroaromatic bidentate, and phosphane ligands were synthesized and fully characterized by elemental analysis, spectroscopic techniques, and DFT methods. The cytotoxicity of all complexes was determined in vitro by the MTS assay in colorectal (HCT116), ovarian (A2780), and breast (MDA-MB-231 and MCF-7) human cancer cell lines and in a healthy human cell line (fibroblasts). The complexes showed high cytotoxicity in cancer cell lines, mostly due to ROS production, apoptosis, autophagy induction, and disruption of the mitochondrial membrane. Also, these complexes were shown to be nontoxic in vivo in an ex ovo chick embryo yolk sac membrane (YSM) assay.


Asunto(s)
Antineoplásicos , Complejos de Coordinación , Neoplasias Ováricas , Animales , Embrión de Pollo , Humanos , Femenino , Línea Celular Tumoral , Antineoplásicos/química , Platino (Metal)/farmacología , Cobalto/farmacología , Complejos de Coordinación/farmacología , Complejos de Coordinación/química , Apoptosis
3.
Neuroradiology ; 66(8): 1251-1265, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38635028

RESUMEN

INTRODUCTION: Diffusion tensor imaging (DTI) is a valuable non-invasive imaging modality for mapping white matter tracts and assessing microstructural integrity, and can be used as a "biomarker" in diagnosis, differentiation, and therapeutic monitoring. Although it has gained clinical importance as a marker of neuropathology, limitations in its interpretation underscore the need for caution. METHODS: This review provides an overview of the principles and clinical applicability of DTI. We focus on major white matter fiber bundles, detailing their normal anatomy and pathological DTI patterns, with emphasis on tracts routinely requested in our neurosurgical department in the preoperative context (uncinate fasciculus, arcuate fasciculus, pyramidal pathway, optic radiation, and dentatorubrothalamic tract). RESULTS: We guide neuroradiologists and neurosurgeons in defining volumes of interest for mapping individual tracts and demonstrating their 3D reconstructions. The intricate trajectories of white matter tracts pose a challenge for accurate fiber orientation recording, with each bundle exhibiting specific characteristics. Tracts adjacent to brain lesions are categorized as displaced, edematous, infiltrated, or disrupted, illustrated with clinical cases of brain neoplasms. To improve structured reporting, we propose a checklist of topics for inclusion in imaging evaluations and MRI reports. CONCLUSION: DTI is emerging as a powerful tool for assessing microstructural changes in brain disorders, despite some challenges in standardization and interpretation. This review serves an educational purpose by providing guidance for fiber monitoring and interpretation of pathological patterns observed in clinical cases, highlighting the importance and potential pitfalls of DTI in neuroradiology and surgical planning.


Asunto(s)
Imagen de Difusión Tensora , Sustancia Blanca , Humanos , Imagen de Difusión Tensora/métodos , Sustancia Blanca/diagnóstico por imagen , Sustancia Blanca/patología , Cuidados Preoperatorios/métodos , Neoplasias Encefálicas/diagnóstico por imagen , Neoplasias Encefálicas/patología , Imagenología Tridimensional/métodos
4.
Telemed J E Health ; 2023 Dec 06.
Artículo en Inglés | MEDLINE | ID: mdl-38054938

RESUMEN

Background: This document represents an updated collaboration between the American Psychiatric Association (APA) and the American Telemedicine Association (ATA) to create a consolidated update of the previous APA and ATA official documents and resources in telemental health, to provide a single guide on clinical best practices for providing mental health services through synchronous videoconference. Methods: A joint writing committee drawn from the APA Committee on Telepsychiatry and the ATA TMH Special Interest Group (TMH SIG). was convened to draft and finalize the guidelines. This document draws directly from the 2018 APA/ATA guide and the ATA s previous guidelines, selecting from key statements/guidelines, consolidating them across documents, and then updating them where indicated. Guideline approval was provided following internal review by the APA, the ATA, the Board of Directors of the ATA, and the Joint Reference Committee of the APA. Results: The guidelines contain requirements, recommendations, and actions that are identified by text containing the keywords "shall," "should," or "may." Conclusions: Compliance with these recommendations will not guarantee accurate diagnoses or successful outcomes. The purpose of this guide is to assist providers in providing effective and safe medical care founded on expert consensus, research evidence, available resources, and patient needs.

5.
Int J Mol Sci ; 24(9)2023 May 03.
Artículo en Inglés | MEDLINE | ID: mdl-37175889

RESUMEN

Urease is a metalloenzyme that catalyzes the hydrolysis of urea, and its modulation has an important role in both the agricultural and medical industry. Even though numerous molecules have been tested against ureases of different species, their clinical translation has been limited due to chemical and metabolic stability as well as side effects. Therefore, screening new compounds against urease would be of interest in part due to rising concerns regarding antibiotic resistance. In this work, we collected and curated a diverse set of 2640 publicly available small-molecule inhibitors of jack bean urease and developed a classifier using a random forest machine learning method with high predictive performance. In addition, the physicochemical features of compounds were paired with molecular docking and protein-ligand fingerprint analysis to gather insight into the current activity landscape. We observed that the docking score could not differentiate active from inactive compounds within each chemical family, but scores were correlated with compound activity when all compounds were considered. Additionally, a decision tree model was built based on 2D and 3D Morgan fingerprints to mine patterns of the known active-class compounds. The final machine learning model showed good prediction performance against the test set (81% and 77% precision for active and inactive compounds, respectively). Finally, this model was employed, as a proof-of-concept, on an in-house library to predict new hits that were then tested against urease and found to be active. This is, to date, the largest, most diverse dataset of compounds used to develop predictive in silico models. Overall, the results highlight the usefulness of using machine learning classifiers and molecular docking to predict novel urease inhibitors.


Asunto(s)
Inhibidores Enzimáticos , Ureasa , Simulación del Acoplamiento Molecular , Ureasa/metabolismo , Inhibidores Enzimáticos/química , Simulación por Computador , Urea
6.
J Child Lang ; 50(1): 27-51, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-36503546

RESUMEN

This study investigates how children aged two to eight years (N = 129) and adults (N = 29) use auditory and visual speech for word recognition. The goal was to bridge the gap between apparent successes of visual speech processing in young children in visual-looking tasks, with apparent difficulties of speech processing in older children from explicit behavioural measures. Participants were presented with familiar words in audio-visual (AV), audio-only (A-only) or visual-only (V-only) speech modalities, then presented with target and distractor images, and looking to targets was measured. Adults showed high accuracy, with slightly less target-image looking in the V-only modality. Developmentally, looking was above chance for both AV and A-only modalities, but not in the V-only modality until 6 years of age (earlier on /k/-initial words). Flexible use of visual cues for lexical access develops throughout childhood.


Asunto(s)
Lectura de los Labios , Percepción del Habla , Adulto , Niño , Humanos , Preescolar , Habla , Desarrollo del Lenguaje , Señales (Psicología)
7.
Plasmid ; 122: 102640, 2022 07.
Artículo en Inglés | MEDLINE | ID: mdl-35870604

RESUMEN

Resistance plasmids mediate the rapid spread of antimicrobial resistance, which poses a threat to veterinary and human healthcare. This study addresses the question whether resistance plasmids from Escherichia coli isolated from foodstuffs always transfer unchanged to recipient E. coli cells, or that genetic editing can occur. Strains containing between one and five different plasmids were co-incubated with a standard recipient strain. Plasmids isolated from transconjugant strains were sequenced using short and long read technologies and compared to the original plasmids from the donor strains. After one hour of co-incubation only a single plasmid was transferred from donor to recipient strains. If the donor possessed several plasmids, longer co-incubation resulted in multiple plasmids being transferred. Transferred plasmids showed mutations, mostly in mobile genetic elements, in the conjugative transfer gene pilV and in genes involved in plasmid maintenance. In one transconjugant, a resistance cluster encoding tetracycline resistance was acquired by the IncI1 plasmid from the IncX1 plasmid that was also present in the donor strain, but that was not transferred. A single plasmid transferred twelve times back and forth between E. coli strains resulted in a fully conserved plasmid with no mutations, apart from repetitive rearrangements of pilV from and back to its original conformation in the donor strain. The overall outcome suggests that some genetic mutations and rearrangements can occur during plasmid transfer. The possibility of such mutations should be taken into consideration in epidemiological research aimed at attribution of resistance to specific sources.


Asunto(s)
Infecciones por Escherichia coli , Escherichia coli , Antibacterianos/farmacología , Conjugación Genética , Escherichia coli/genética , Transferencia de Gen Horizontal , Humanos , Carne , Plásmidos/genética
8.
Nature ; 595(7867): 357-358, 2021 07.
Artículo en Inglés | MEDLINE | ID: mdl-34262217
9.
Bioconjug Chem ; 32(7): 1399-1408, 2021 07 21.
Artículo en Inglés | MEDLINE | ID: mdl-33440122

RESUMEN

The biomedical application of discrete supramolecular metal-based structures, specifically self-assembled metallacages, is still an emergent field of study. Capitalizing on the knowledge gained in recent years on the development of 3-dimensional (3D) metallacages as novel drug delivery systems and theranostic agents, we explore here the possibility to target [Pd2L4]4+ cages (L = 3,5-bis(3-ethynylpyridine)phenyl ligand) to the brain. In detail, a new water-soluble homoleptic cage (CPepH3) tethered to a blood brain barrier (BBB)-translocating peptide was synthesized by a combination of solid-phase peptide synthesis (SPPS) and self-assembly procedures. The cage translocation efficacy was assessed by inductively coupled mass spectrometry (ICP-MS) in a BBB cellular model in vitro. Biodistribution studies of the radiolabeled cage [[99mTcO4]- ⊂ CPepH3] in the CD1 mice model demonstrate its brain penetration properties in vivo. Further DFT studies were conducted to model the structure of the [[99mTcO4]- ⊂ cage] complex. Moreover, the encapsulation capabilities and stability of the cage were investigated using the [ReO4]- anion, the "cold" analogue of [99mTcO4]-, by 1H NMR spectroscopy. Overall, our study constitutes another proof-of-concept of the unique potential of supramolecular coordination complexes for modifying the physiochemical and biodistribution properties of diagnostic species.


Asunto(s)
Barrera Hematoencefálica , Paladio/química , Animales , Teoría Funcional de la Densidad , Sistemas de Liberación de Medicamentos/métodos , Técnicas In Vitro , Ligandos , Espectrometría de Masas/métodos , Ratones , Espectroscopía de Protones por Resonancia Magnética/métodos , Distribución Tisular , Tomografía Computarizada de Emisión de Fotón Único
10.
Invest New Drugs ; 39(2): 400-415, 2021 04.
Artículo en Inglés | MEDLINE | ID: mdl-33063290

RESUMEN

Lactoferrin has gained extensive attention due to its ample biological properties. In this study, recombinant human lactoferrin carrying humanized glycosylation (rhLf-h-glycan) expressed in the yeast Pichia pastoris SuperMan5, which is genetically glycoengineered to efficiently produce functional humanized glycoproteins inclosing (Man)5(GlcNAc)2 Asn-linked glycans, was analyzed, inspecting its potential toxicity against cancer cells. The live-cell differential nuclear staining assay was used to quantify the rhLf-h-glycan cytotoxicity, which was examined in four human cell lines: acute lymphoblastic leukemia (ALL) CCRF-CEM, T-cell lymphoblastic lymphoma SUP-T1, cervical adenocarcinoma HeLa, and as control, non-cancerous Hs27 cells. The defined CC50 values of rhLf-h-glycan in CCRF-CEM, SUP-T1, HeLa, and Hs27 cells were 144.45 ± 4.44, 548.47 ± 64.41, 350 ± 14.82, and 3359.07 ± 164 µg/mL, respectively. The rhLf-h-glycan exhibited a favorable selective cytotoxicity index (SCI), preferentially killing cancer cells: 23.25 for CCRF-CEM, 9.59 for HeLa, and 6.12 for SUP-T1, as compared with Hs27 cells. Also, rhLf-h-glycan showed significant antiproliferative activity (P < 0.0001) at 24, 48, and 72 h of incubation on CCRF-CEM cells. Additionally, it was observed via fluorescent staining and confocal microscopy that rhLf-h-glycan elicited apoptosis-associated morphological changes, such as blebbing, nuclear fragmentation, chromatin condensation, and apoptotic bodies in ALL cells. Furthermore, rhLf-h-glycan-treated HeLa cells revealed shrinkage of the microfilament structures, generating a speckled/punctuated pattern and also caused PARP-1 cleavage, a hallmark of apoptosis. Moreover, in ALL cells, rhLf-h-glycan altered cell cycle progression inducing the G2/M phase arrest, and caused apoptotic DNA fragmentation. Overall, our findings revealed that rhLf-h-glycan has potential as an anticancer agent and therefore deserves further in vivo evaluation.


Asunto(s)
Citoesqueleto de Actina/efectos de los fármacos , Apoptosis/efectos de los fármacos , Puntos de Control del Ciclo Celular/efectos de los fármacos , Lactoferrina/farmacología , Línea Celular Tumoral , Células HeLa , Humanos , Proteínas Recombinantes , Saccharomycetales
11.
AJR Am J Roentgenol ; 216(1): 132-140, 2021 01.
Artículo en Inglés | MEDLINE | ID: mdl-33236946

RESUMEN

OBJECTIVE. The purpose of this study was to determine whether the relative length of protrusion of the second metatarsal, measured on MRI and weight-bearing foot radiography, predicts the diagnosis of second metatarsophalangeal (MTP) joint plantar plate (PP) tear on MRI. MATERIALS AND METHODS. We retrospectively evaluated 166 consecutive patients (211 feet). Patients had undergone weight-bearing foot radiography and forefoot MRI. Using the Coughlin method, two independent observers measured second meta-tarsal protrusion length on radiography and MRI. MRI findings were classified as normal PP, complete PP tear, or degenerative or partial PP tear. RESULTS. Patients had a mean age of 47 ± 14.6 (SD) years, and 131 (78.9%) were women. MRI measurements were highly correlated with radiographic measurements (r = 0.882; 95% CI, 0.866-0.898; p < 0.001). A significant correlation was found between length of protrusion and cases classified as either normal PP or PP tear. Patients with a normal PP had a mean protrusion length of 4.11 ± 1.35 mm on radiographs and 2.61 ± 1.31 mm on MR images, whereas those with a PP tear had a mean protrusion length of 4.75 ± 1.53 and 3.05 ± 1.34 mm, respectively. ROC curve analysis showed that protrusion length cutoff values of 5.47 mm measured on radiographs and 3.17 mm on MR images were correlated with MTP PP tear. CONCLUSION. We identified a linear correlation between second metatarsal protrusion measured on MRI and that measured on radiography, with values about 35% higher for the latter. Our study showed an association between length of protrusion of the second metatarsal and PP rupture and identified a cutoff value for the second meta-tarsal overlength that is associated with these tears.


Asunto(s)
Huesos Metatarsianos/diagnóstico por imagen , Articulación Metatarsofalángica/diagnóstico por imagen , Placa Plantar/diagnóstico por imagen , Placa Plantar/lesiones , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Valor Predictivo de las Pruebas , Curva ROC , Rango del Movimiento Articular , Reproducibilidad de los Resultados , Estudios Retrospectivos , Rotura , Soporte de Peso , Adulto Joven
12.
Biometals ; 34(5): 1029-1042, 2021 10.
Artículo en Inglés | MEDLINE | ID: mdl-34155581

RESUMEN

The interaction between human serum transferrin (hTf) and three promising organometallic Ru (II)- (η5-C5H5) derived complexes, that have already shown strong in vitro cytotoxicity towards human cancer cell lines, has been investigated using fluorescence spectroscopic techniques. The results suggested that the formation of Ru-hTf systems involves a dynamic collision. The binding process occurs spontaneously (ΔG < 0), mainly driven by hydrophobic interactions. Additional docking studies show that all complexes bind preferably to a specific hydrophobic pocket in the C2-subdomain as already observed for other metal-cyclopentadienyl (MCp) complexes and are in agreement with the experimental results. With these studies we hope to contribute to the understanding of the mechanism of action of these promising cytotoxic agents, thus providing clues for a more rational design.


Asunto(s)
Antineoplásicos , Complejos de Coordinación , Rutenio , Antineoplásicos/química , Complejos de Coordinación/química , Humanos , Simulación del Acoplamiento Molecular , Unión Proteica , Rutenio/química , Espectrometría de Fluorescencia , Transferrina/química
13.
Child Dev ; 92(6): 2447-2464, 2021 11.
Artículo en Inglés | MEDLINE | ID: mdl-34406649

RESUMEN

Research has found mixed evidence for the production effect in childhood. Some studies have found a positive effect of production on word recognition and recall, while others have found the reverse. This paper takes a developmental approach to investigate the production effect. Children aged 2-6 years (n = 150) from a predominantly white population in Ottawa, Canada were trained on familiar words which were either seen, heard or produced, followed by a recall task. Results showed a developmental shift: younger participants showed a reverse production effect, recalling more words that were heard during training, while older children showed the typical production effect, recalling more produced words. The effect of production on recall is not unidirectional and varies by age.


Asunto(s)
Recuerdo Mental , Adolescente , Factores de Edad , Canadá , Niño , Humanos
14.
Endocr Pract ; 27(6): 567-570, 2021 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-33798738

RESUMEN

OBJECTIVE: To examine the performance and agreement of 5 modalities for testing sensory neuropathy against a neurothesiometer among Hispanic patients with type 1 diabetes (T1D) in an outpatient setting. METHODS: A cross-sectional study was conducted at a tertiary reference center in Mexico City. Sensitivity, specificity, predictive values, and likelihood ratios were calculated using a VibraTip device, 128 Hz tuning fork, and the Semmes-Weinstein 5.07/10 g monofilament test, Ipswich touch test (IpTT), and pinprick test (PPT). The VPT obtained using a neurothesiometer was used as the standard. Agreement between tests was calculated using kappa coefficients. RESULTS: Our study included 78 patients (156 examinations), of whom 56.4% were females. The mean age was 38.2 ± 13.0 years, and the mean body mass index was 24.6 ± 4.8 kg/m2. The best sensitivity was found for IpTT and VibraTip (89.7% and 79.3%, respectively), while the PPT and IpTT had the highest positive predictive values (94.4% and 92.9%, respectively). The highest kappa coefficients were obtained for the IpTT vs neurothesiometer (kappa coefficient [κ] = 0.893, P < .001), followed by VibraTip vs neurothesiometer (κ = 0.782, P < .001). The VibraTip vs IpTT also had a substantial agreement (κ= 0.713, P < .001). CONCLUSION: Our findings demonstrated that the IpTT had the best diagnostic performance and agreement compared with the standard in this cohort of Hispanic patients with T1D. The IpTT is a useful, simple test for diabetic neuropathy screening. These findings support its inclusion in future guidelines for diabetic foot examination.


Asunto(s)
Diabetes Mellitus Tipo 1 , Neuropatías Diabéticas , Adulto , Estudios Transversales , Diabetes Mellitus Tipo 1/complicaciones , Diabetes Mellitus Tipo 1/diagnóstico , Neuropatías Diabéticas/diagnóstico , Femenino , Humanos , Masculino , México , Persona de Mediana Edad , Vibración
15.
Int J Mol Sci ; 22(17)2021 Aug 26.
Artículo en Inglés | MEDLINE | ID: mdl-34502136

RESUMEN

Plasmids play a crucial role in spreading antimicrobial resistance genes. Plasmids have many ways to incorporate various genes. By inducing amoxicillin resistance in Escherichia coli, followed by horizontal gene transfer experiments and sequencing, we show that the chromosomal beta-lactamase gene ampC is multiplied and results in an 8-13 kb contig. This contig is comparable to a transposon, showing similarities to variable regions found in environmental plasmids, and can be transferred between E. coli cells. As in eight out of nine replicate strains an almost completely identical transposon was isolated, we conclude that this process is under strict control by the cell. The single transposon that differed was shortened at both ends, but otherwise identical. The outcome of this study indicates that as a result of exposure to beta-lactam antibiotics, E. coli can form a transposon containing ampC that can subsequently be integrated into plasmids or genomes. This observation offers an explanation for the large diversity of genes in plasmids found in nature and proposes mechanisms by which the dynamics of plasmids are maintained.


Asunto(s)
Elementos Transponibles de ADN , Proteínas de Escherichia coli/genética , Resistencia betalactámica , beta-Lactamasas/genética , Amoxicilina/toxicidad , Antibacterianos/toxicidad , Escherichia coli , Transferencia de Gen Horizontal
16.
Molecules ; 26(11)2021 May 25.
Artículo en Inglés | MEDLINE | ID: mdl-34070457

RESUMEN

Cisplatin and derivatives are highly effective in the treatment of a wide range of cancer types; however, these metallodrugs display low selectivity, leading to severe side effects. Additionally, their administration often results in the development of chemoresistance, which ultimately results in therapeutic failure. This scenario triggered the study of other transition metals with innovative pharmacological profiles as alternatives to platinum, ruthenium- (e.g., KP1339 and NAMI-A) and gold-based (e.g., Auranofin) complexes being among the most advanced in terms of clinical evaluation. Concerning the importance of improving the in vivo selectivity of metal complexes and the current relevance of ruthenium and gold metals, this review article aims to survey the main research efforts made in the past few years toward the design and biological evaluation of target-specific ruthenium and gold complexes. Herein, we give an overview of the inorganic and organometallic molecules conjugated to different biomolecules for targeting membrane proteins, namely cell adhesion molecules, G-protein coupled receptors, and growth factor receptors. Complexes that recognize the progesterone receptors or other targets involved in metabolic pathways such as glucose transporters are discussed as well. Finally, we describe some complexes aimed at recognizing cell organelles or compartments, mitochondria being the most explored. The few complexes addressing targeted gene therapy are also presented and discussed.


Asunto(s)
Antineoplásicos/farmacología , Complejos de Coordinación/farmacología , Compuestos de Oro/farmacología , Compuestos de Rutenio/farmacología , Antineoplásicos/administración & dosificación , Moléculas de Adhesión Celular/efectos de los fármacos , Línea Celular Tumoral , Complejos de Coordinación/administración & dosificación , Compuestos de Oro/administración & dosificación , Humanos , Receptores Acoplados a Proteínas G/efectos de los fármacos , Receptores de Factores de Crecimiento/efectos de los fármacos , Compuestos de Rutenio/administración & dosificación
17.
Molecules ; 26(1)2021 Jan 03.
Artículo en Inglés | MEDLINE | ID: mdl-33401580

RESUMEN

Lactoferrin is an iron binding glycoprotein with multiple roles in the body. Its participation in apoptotic processes in cancer cells, its ability to modulate various reactions of the immune system, and its activity against a broad spectrum of pathogenic microorganisms, including respiratory viruses, have made it a protein of broad interest in pharmaceutical and food research and industry. In this review, we have focused on describing the most important functions of lactoferrin and the possible mechanisms of action that lead to its function.


Asunto(s)
Antiinfecciosos/metabolismo , Antineoplásicos/metabolismo , Factores Inmunológicos/metabolismo , Lactoferrina/metabolismo , Animales , Humanos
18.
Molecules ; 26(23)2021 Dec 03.
Artículo en Inglés | MEDLINE | ID: mdl-34885928

RESUMEN

Considering our interest in the use of peptides as potential target-specific drugs or as delivery vectors of metallodrugs for various biomedical applications, it is crucial to explore improved synthetic methodologies to accomplish the highest peptide crude purity in the shortest time possible. Therefore, we compared "classical" fluorenylmethoxycarbonyl (Fmoc)-solid phase peptide synthesis (SPPS) with ultrasound(US)-assisted SPPS based on the preparation of three peptides, namely the fibroblast growth factor receptor 3(FGFR3)-specific peptide Pep1 (VSPPLTLGQLLS-NH2) and the novel peptides Pep2 (RQMATADEA-NH2) and Pep3 (AAVALLPAVLLALLAPRQMATADEA-NH2), which are being developed aimed at interfering with the intracellular protein-protein interaction(PPI) RANK-TRAF6. Our results demonstrated that US-assisted SPPS led to a 14-fold (Pep1) and 4-fold time reduction (Pep2) in peptide assembly compared to the "classical" method. Interestingly, US-assisted SPPS yielded Pep1 in higher purity (82%) than the "classical" SPPS (73%). The significant time reduction combined with high crude peptide purity attained prompted use to apply US-assisted SPPS to the large peptide Pep3, which displays a high number of hydrophobic amino acids and homooligo-sequences. Remarkably, the synthesis of this 25-mer peptide was attained during a "working day" (347 min) in moderate purity (approx. 49%). In conclusion, we have reinforced the importance of using US-SPPS towards facilitating the production of peptides in shorter time with increased efficacy in moderate to high crude purity. This is of special importance for long peptides such as the case of Pep3.


Asunto(s)
Péptidos/síntesis química , Técnicas de Síntesis en Fase Sólida/métodos , Humanos , Péptidos/química , Receptor Activador del Factor Nuclear kappa-B/química , Receptores de Factores de Crecimiento de Fibroblastos/química , Sonicación/métodos , Factor 6 Asociado a Receptor de TNF/química
19.
J Infect Dis ; 222(12): 1974-1984, 2020 11 13.
Artículo en Inglés | MEDLINE | ID: mdl-32910175

RESUMEN

BACKGROUND: Convalescent plasma therapy is a leading treatment for conferring temporary immunity to COVID-19-susceptible individuals or for use as post-exposure prophylaxis. However, not all recovered patients develop adequate antibody titers for donation and the relationship between avidity and neutralizing titers is currently not well understood. METHODS: SARS-CoV-2 anti-spike and anti-nucleocapsid IgG titers and avidity were measured in a longitudinal cohort of COVID-19 hospitalized patients (n = 16 individuals) and a cross-sectional sample of convalescent plasma donors (n = 130). Epidemiologic correlates of avidity were examined in donors by linear regression. The association of avidity and a high neutralizing titer (NT) were also assessed in donors using modified Poisson regression. RESULTS: Antibody avidity increased over duration of infection and remained elevated. In convalescent plasma donors, higher levels of anti-spike avidity were associated with older age, male sex, and hospitalization. Higher NTs had a stronger positive correlation with anti-spike IgG avidity (Spearman ρ = 0.386; P < .001) than with anti-nucleocapsid IgG avidity (Spearman ρ = 0.211; P = .026). Increasing levels of anti-spike IgG avidity were associated with high NT (≥160) (adjusted prevalence ratio = 1.58 [95% confidence interval = 1.19-2.12]), independent of age, sex, and hospitalization. CONCLUSIONS: SARS-CoV-2 antibody avidity correlated with duration of infection and higher neutralizing titers, suggesting a potential alternative screening parameter for identifying optimal convalescent plasma donors.


Asunto(s)
Anticuerpos Neutralizantes/administración & dosificación , Anticuerpos Antivirales/administración & dosificación , Afinidad de Anticuerpos , COVID-19/terapia , Inmunoglobulina G/administración & dosificación , SARS-CoV-2 , Adolescente , Adulto , Anticuerpos Neutralizantes/sangre , Anticuerpos Antivirales/sangre , Donantes de Sangre , Estudios de Cohortes , Estudios Transversales , Femenino , Humanos , Inmunización Pasiva , Inmunoglobulina G/sangre , Modelos Lineales , Masculino , Persona de Mediana Edad , Glicoproteína de la Espiga del Coronavirus/inmunología , Adulto Joven , Sueroterapia para COVID-19
20.
Plant J ; 99(2): 270-285, 2019 07.
Artículo en Inglés | MEDLINE | ID: mdl-30900785

RESUMEN

Compartmentation of photosynthetic reactions between mesophyll and bundle sheath cells is a key feature of C4 photosynthesis and depends on the cell-specific accumulation of major C4 enzymes, such as phosphoenolpyruvate carboxylase 1. The ZmPEPC1 upstream region, which drives light-inducible and mesophyll-specific gene expression in maize, has been shown to keep the same properties when introduced into rice (C3 plant), indicating that rice has the transcription factors (TFs) needed to confer C4 -like gene expression. Using a yeast one-hybrid approach, we identified OsbHLH112, a rice basic Helix-Loop-Helix (bHLH) TF that interacts with the maize ZmPEPC1 upstream region. Moreover, we found that maize OsbHLH112 homologues, ZmbHLH80, and ZmbHLH90, also interact with the ZmPEPC1 upstream region, suggesting that these C4 regulators were co-opted from C3 plants. A transactivation assay in maize mesophyll protoplasts revealed that ZmbHLH80 represses, whereas ZmbHLH90 activates, ZmPEPC1 expression. In addition, ZmbHLH80 was shown to impair the ZmPEPC1 promoter activation caused by ZmbHLH90. We showed that ZmbHLH80 and ZmbHLH90 bind to the same cis-element within the ZmPEPC1 upstream region either as homodimers or heterodimers. The formation of homo- and heterodimers with higher oligomeric forms promoted by ZmbHLH80 may explain its negative effect on gene transcription. Gene expression analysis revealed that ZmbHLH80 is preferentially expressed in bundle sheath cells, whereas ZmbHLH90 does not show a clear cell-specific expression pattern. Altogether, our results led us to propose a model in which ZmbHLH80 contributes to mesophyll-specific ZmPEPC1 gene expression by impairing ZmbHLH90-mediated ZmPEPC1 activation in the bundle sheath cells.


Asunto(s)
Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/fisiología , Proteínas de Plantas/fisiología , Zea mays/genética , Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/genética , Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/metabolismo , Regulación de la Expresión Génica de las Plantas , Técnicas de Sonda Molecular , Oryza/genética , Fotosíntesis/genética , Proteínas de Plantas/genética , Regiones Promotoras Genéticas , Zea mays/metabolismo
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