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1.
Langmuir ; 2024 Jul 18.
Artículo en Inglés | MEDLINE | ID: mdl-39024338

RESUMEN

Metal core and dielectric shell nanoparticles (NPs) have garnered considerable attention for their multifaceted properties and extensive applications across diverse fields of nanoscience and nanotechnology. However, a literature gap exists regarding the impact of assembled metallic nanostar cores within a single shell, particularly concerning surface-enhanced Raman scattering (SERS) and electrochemical sensing. In this study, we have demonstrated the better performance of assemblies of gold nanostars (AuNSs) enclosed in single silica shell for SERS enhancement and electrocatalytic activity, particularly in the fields of ascorbic acid (AA) and glucose sensing. We have devised a method to isolate and passivate nanostar assemblies, ranging from 2 to 30 nanostars per assembly, with a functionalized silica (SiO2) shell, facilitating their preservation. The engineered thickness of the silica shell ensures unhindered optical measurements while elucidating the influence of multiple AuNS cores. Due to the formation of nanogaps and nanojunctions between AuNSs within assembly, we have achieved a maximum SERS enhancement factor (EF) of 1.416 × 1010 for the rhodamine 6G analyte. Utilizing assembled AuNS cores within a single silica shell, we have demonstrated AA (sensitivity of 5.278 × 10-5 µA µM-1 cm-2) and glucose (sensitivity of 7.519 × 10-4 µA µM-1 cm-2) sensing via a nonenzymatic electrochemical pathway.

2.
Neurocrit Care ; 40(1): 130-146, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-37160846

RESUMEN

BACKGROUND: Noninvasive neuromonitoring in critically ill children includes multiple modalities that all intend to improve our understanding of acute and ongoing brain injury. METHODS: In this article, we review basic methods and devices, applications in clinical care and research, and explore potential future directions for three noninvasive neuromonitoring modalities in the pediatric intensive care unit: automated pupillometry, near-infrared spectroscopy, and transcranial Doppler ultrasonography. RESULTS: All three technologies are noninvasive, portable, and easily repeatable to allow for serial measurements and trending of data over time. However, a paucity of high-quality data supporting the clinical utility of any of these technologies in critically ill children is currently a major limitation to their widespread application in the pediatric intensive care unit. CONCLUSIONS: Future prospective multicenter work addressing major knowledge gaps is necessary to advance the field of pediatric noninvasive neuromonitoring.


Asunto(s)
Lesiones Encefálicas , Ultrasonografía Doppler Transcraneal , Humanos , Niño , Ultrasonografía Doppler Transcraneal/métodos , Espectroscopía Infrarroja Corta , Enfermedad Crítica , Unidades de Cuidado Intensivo Pediátrico , Estudios Multicéntricos como Asunto
3.
Pediatr Res ; 93(5): 1199-1207, 2023 04.
Artículo en Inglés | MEDLINE | ID: mdl-35273370

RESUMEN

BACKGROUND: Neuroprognostication in neonates with neonatal encephalopathy (NE) may be enhanced by early serial measurement of a panel of four brain-specific biomarkers. METHODS: To evaluate serum biomarkers, 40 NE samples and 37 healthy neonates from a biorepository were analyzed. Blood samples were collected at 0-6, 12, 24, 48, and 96 h of life. MRI provided a short-term measure of injury. Long-term outcomes included death or a Bayley III score at 17-24 months of age. RESULTS: Glial fibrillary acidic protein (GFAP), ubiquitin c-terminal hydrolase-L1 (UCH-L1), and Tau peaked at 0-6 h of life, while neurofilament light chain (NFL) peaked at 96 h of life. These four marker concentrations at 96 h of life differentiated moderate/severe from none/mild brain injury by MRI, while GFAP and Tau showed early discrimination. For long-term outcomes, GFAP, NFL, Tau, and UCH-L1 could differentiate a poor outcome vs good outcome as early as 0-6 h of life, depending on the Bayley domain, and a combination of the four markers enhanced the sensitivity and specificity. Machine learning trajectory analyses identified upward trajectory patients with a high concordance to poor outcomes. CONCLUSION: GFAP, NFL, Tau, and UCH-L1 may be of neuroprognostic significance after NE. IMPACT: Serial measurements of GFAP, NFL, Tau, and UCH-L1 show promise in aiding the bedside clinician in making treatment decisions in neonatal encephalopathy. The panel of four neuroproteins increased the ability to predict neurodevelopmental outcomes. The study utilized a trajectory analysis that enabled predictive modeling. A panel approach provides the bedside clinician with objective data to individualize care. This study provides the foundation to develop a point of care device in the future.


Asunto(s)
Lesiones Encefálicas , Filamentos Intermedios , Recién Nacido , Humanos , Proteína Ácida Fibrilar de la Glía , Ubiquitina Tiolesterasa , Biomarcadores
4.
Environ Res ; 217: 114922, 2023 01 15.
Artículo en Inglés | MEDLINE | ID: mdl-36435492

RESUMEN

Carbon dots (CDs) are an exquisite class of carbon allotrope that is already well nourished for their good biocompatibility, water-solubility, excellent photostability, and magnificent photoluminescence property. Doping strategy with heteroatoms is an efficacious way to modify the physicochemical and optical properties, making the carbon dots an exceedingly potential candidate. This work reports the fabrication and cancer cell imaging application of photoluminescent heteroatom-doped carbon dots by use of cysteine and urea as carbon, nitrogen, and sulphur sources through a straightforward and highly productive hydrothermal procedure. The fabricated luminescent carbon dots are spherical in shape, with an average diameter of 3.5 nm. X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD), and Fourier transform infrared spectroscopy (FTIR) characterization revealed key facts about the surface functional groups and chemical compositions of carbon dots. The excitation-dependent photoluminescence (PL) peak appeared at around 445 nm against the excited wavelength of 350 nm. Moreover, under the provided experimental conditions, all the carbon dots are non-toxic and safe. The cytotoxicity and the safety profiles of the carbon dots were found to be in the bearable range under normal in-vitro experimental circumstances. Cellular uptake was observed by the green fluorescence of carbon dots inside cells. Likewise, the carbon dots did not alter the cell viability of the normal glial cell line. Again, when treated with the carbon dots, there was no notable increase of apoptotic cells in the G2/M phase of cell cycle analysis that confirmed the imaging-trackable ability of the carbon dots.


Asunto(s)
Carbono , Neoplasias , Carbono/química , Nitrógeno , Espectroscopía de Fotoelectrones , Espectroscopía Infrarroja por Transformada de Fourier , Azufre
5.
Childs Nerv Syst ; 38(1): 203-206, 2022 01.
Artículo en Inglés | MEDLINE | ID: mdl-33830323

RESUMEN

INTRODUCTION: Influenza virus has been associated with cases of Parkinsonism, yet a direct relationship has not been confirmed in the literature. Different mechanisms of post-infectious Parkinsonism have been proposed including inflammatory, oxidative stress, and autoimmune. We report a first to our knowledge case of pediatric autoimmune Parkinsonism with autoantibodies to dopamine D2L receptor (anti-DRD2L antibodies), who underwent deep brain stimulation (DBS) of bilateral globus pallidi (GPi). CASE REPORT: A 13-year-old girl presented with Parkinsonism features after a severe case of influenza A. She underwent extensive work-up and was found to have elevated titers for anti-DRD2L antibodies. Patient was initially treated with IVIG and plasmapheresis with mild improvement, but her condition continued to worsen. She was responsive to levodopa; however, she developed severe dyskinesia. Patient underwent DBS implantation resulting in partial improvement in bradykinesia, tremors, and dyskinesia. CONCLUSION: This case is meant to raise awareness of a rare potential autoimmune complication after influenza virus and to share the experience and outcome using DBS to palliate some of the symptoms.


Asunto(s)
Estimulación Encefálica Profunda , Trastornos Parkinsonianos , Adolescente , Niño , Estimulación Encefálica Profunda/métodos , Femenino , Globo Pálido/cirugía , Humanos , Levodopa , Trastornos Parkinsonianos/terapia , Resultado del Tratamiento , Temblor
6.
Chaos Solitons Fractals ; 142: 110377, 2021 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-33100606

RESUMEN

Most of the widely populated countries across the globe have been observing vicious spread and detrimental effects of pandemic COVID-19 since its inception on December 19. Therefore to restrict the spreading of pandemic COVID-19, various researches are going on in both medical and administrative sectors. The focus has been given in this research keeping an administrative point of view in mind. In this paper a dynamic model of infected population due to spreading of pandemic COVID-19 considering both intra and inter zone mobilization factors with rate of detection has been proposed. Few factors related to intra zone mobilization; inter zone mobilization and rate of detection are the key points in the proposed model. Various remedial steps are taken into consideration in the form of operating procedures. Further such operating procedures are applied over the model in standalone or hybridized mode and responses are reported in this paper in a case-studies manner. Further zone-wise increase in infected population due to the spreading of pandemic COVID-19 has been studied and reported in this paper. Also the proposed model has been applied over the real world data considering three states of India and the predicted responses are compared with real data and reported with bar chart representation in this paper.

7.
J Inherit Metab Dis ; 43(6): 1333-1348, 2020 11.
Artículo en Inglés | MEDLINE | ID: mdl-32681751

RESUMEN

Asparagine-linked glycosylation 13 homolog (ALG13) encodes a nonredundant, highly conserved, X-linked uridine diphosphate (UDP)-N-acetylglucosaminyltransferase required for the synthesis of lipid linked oligosaccharide precursor and proper N-linked glycosylation. De novo variants in ALG13 underlie a form of early infantile epileptic encephalopathy known as EIEE36, but given its essential role in glycosylation, it is also considered a congenital disorder of glycosylation (CDG), ALG13-CDG. Twenty-four previously reported ALG13-CDG cases had de novo variants, but surprisingly, unlike most forms of CDG, ALG13-CDG did not show the anticipated glycosylation defects, typically detected by altered transferrin glycosylation. Structural homology modeling of two recurrent de novo variants, p.A81T and p.N107S, suggests both are likely to impact the function of ALG13. Using a corresponding ALG13-deficient yeast strain, we show that expressing yeast ALG13 with either of the highly conserved hotspot variants rescues the observed growth defect, but not its glycosylation abnormality. We present molecular and clinical data on 29 previously unreported individuals with de novo variants in ALG13. This more than doubles the number of known cases. A key finding is that a vast majority of the individuals presents with West syndrome, a feature shared with other CDG types. Among these, the initial epileptic spasms best responded to adrenocorticotropic hormone or prednisolone, while clobazam and felbamate showed promise for continued epilepsy treatment. A ketogenic diet seems to play an important role in the treatment of these individuals.


Asunto(s)
Trastornos Congénitos de Glicosilación/genética , N-Acetilglucosaminiltransferasas/deficiencia , N-Acetilglucosaminiltransferasas/genética , Espasmos Infantiles/genética , Biomarcadores , Preescolar , Trastornos Congénitos de Glicosilación/diagnóstico , Dieta Cetogénica , Femenino , Glicosilación , Humanos , Lactante , Masculino , Mutación , N-Acetilglucosaminiltransferasas/química , Espasmos Infantiles/diagnóstico , Transferrina/metabolismo
8.
Proc Natl Acad Sci U S A ; 114(36): 9707-9712, 2017 09 05.
Artículo en Inglés | MEDLINE | ID: mdl-28827321

RESUMEN

The microtubule-associated protein tau (MAPT, tau) forms neurotoxic aggregates that promote cognitive deficits in tauopathies, the most common of which is Alzheimer's disease (AD). The 90-kDa heat shock protein (Hsp90) chaperone system affects the accumulation of these toxic tau species, which can be modulated with Hsp90 inhibitors. However, many Hsp90 inhibitors are not blood-brain barrier-permeable, and several present associated toxicities. Here, we find that the cochaperone, activator of Hsp90 ATPase homolog 1 (Aha1), dramatically increased the production of aggregated tau. Treatment with an Aha1 inhibitor, KU-177, dramatically reduced the accumulation of insoluble tau. Aha1 colocalized with tau pathology in human brain tissue, and this association positively correlated with AD progression. Aha1 overexpression in the rTg4510 tau transgenic mouse model promoted insoluble and oligomeric tau accumulation leading to a physiological deficit in cognitive function. Overall, these data demonstrate that Aha1 contributes to tau fibril formation and neurotoxicity through Hsp90. This suggests that therapeutics targeting Aha1 may reduce toxic tau oligomers and slow or prevent neurodegenerative disease progression.


Asunto(s)
Proteínas HSP90 de Choque Térmico/metabolismo , Chaperonas Moleculares/metabolismo , Enfermedad de Alzheimer/etiología , Enfermedad de Alzheimer/metabolismo , Enfermedad de Alzheimer/patología , Animales , Encéfalo/metabolismo , Encéfalo/patología , Línea Celular , Modelos Animales de Enfermedad , Femenino , Humanos , Masculino , Ratones , Ratones Transgénicos , Chaperonas Moleculares/antagonistas & inhibidores , Chaperonas Moleculares/genética , Agregado de Proteínas , Agregación Patológica de Proteínas/etiología , Agregación Patológica de Proteínas/metabolismo , Agregación Patológica de Proteínas/prevención & control , Tauopatías/etiología , Tauopatías/metabolismo , Tauopatías/prevención & control , Proteínas tau/química , Proteínas tau/metabolismo
9.
J Am Chem Soc ; 141(44): 17503-17506, 2019 11 06.
Artículo en Inglés | MEDLINE | ID: mdl-31630516

RESUMEN

Herein we report a facile transformation of hydroxylated cucurbit[n]uril (CB[n], n = 6 and 7) to other functionality-conjugated CB[n]s by nucleophilic substitution of the hydroxyl group with a wide range of nitriles and alcohols. The reaction proceeds efficiently via generation of a superelectrophilic carbocation on the CB framework from hydroxylated CB[n]s under superacidic conditions. One of the resulting CB[n] derivatives with reactive functionality, monocarboxylated CB[7], is efficiently conjugated to an enzyme (horseradish peroxidase, HRP) by amide coupling. This provides a CB[7]-conjugated functional biomaterial (CB[7]-HRP) that selectively detects proteins labeled with a guest, adamantylammonium (AdA), based on bioorthogonal high-affinity host-guest interactions between CB[7] and AdA. We demonstrated the potential of overcoming the limitations in preparing reactive functional CB[n] derivatives, enabling the exploration of novel bioapplications of CB[n]-based host-guest chemistry with new CB[n]-conjugated functional materials.

10.
Childs Nerv Syst ; 35(9): 1571-1578, 2019 09.
Artículo en Inglés | MEDLINE | ID: mdl-31278442

RESUMEN

PURPOSE: Infants with brain injury are susceptible to developmental delays. Survivors of neonatal seizures are at risk for developmental delay, epilepsy, and further neurological comorbidities. Despite advances in neonatal critical care, the prevalence of adverse long-term outcomes and seizure recurrence remains unchanged. Our goal is to determine if early treatment of neonatal seizures with phenobarbital or levetiracetam is associated with worse neurodevelopmental outcomes in brain-injured infants. METHODS: We conducted a retrospective cohort study of 119 infants admitted between 2013 and 2017 who were at risk for developmental delay and assessed in our clinic. We compared brain injury infants with neonatal seizures to brain injury infants without neonatal seizures using Bayley scores (BSID III) at 9-14 months gestational age. A comparison of Bayley scores between those exposed to phenobarbital and levetiracetam was conducted. RESULTS: Twenty-two children with neonatal seizures scored lower than 53 children without seizures in all domains with significant values in composite scores for cognitive function (p = 0.003) and language (p = 0.031). We found no difference in scores at 9-14 months between infants exposed to phenobarbital versus levetiracetam. CONCLUSIONS: Our results suggest that in infants with brain injury, the occurrence of neonatal seizures has an adverse effect on neurodevelopmental outcomes. The choice of antiseizure medication may not play a significant role in their outcomes.


Asunto(s)
Lesiones Encefálicas/complicaciones , Discapacidades del Desarrollo/etiología , Convulsiones/etiología , Anticonvulsivantes/uso terapéutico , Estudios de Casos y Controles , Femenino , Edad Gestacional , Humanos , Lactante , Levetiracetam/uso terapéutico , Masculino , Fenobarbital/uso terapéutico , Estudios Retrospectivos , Convulsiones/tratamiento farmacológico
11.
Angew Chem Int Ed Engl ; 58(47): 16850-16853, 2019 Nov 18.
Artículo en Inglés | MEDLINE | ID: mdl-31544353

RESUMEN

Transient self-assembling systems often suffer from accumulation of chemical wastes that interfere with the formation of pristine self-assembled products in subsequent cycles. Herein, we report the transient crystallization of a cucurbit[8]uril-based host-guest complex, preventing the accumulation of chemical wastes. Base-catalyzed thermal decarboxylation of trichloroacetic acid that chemically fuels the crystallization process dissolves the crystals, and produces volatile chemical wastes that are spontaneously removed from the solution. With such self-clearance process, no significant damping in the formation of the crystals was observed. The morphology and structural integrity of the crystals was also maintained in subsequent cycles. The concept may be further extended to obtain other temporally functional materials, quasicrystals, etc., based on stimuli-responsive guest molecules.

12.
J Biol Chem ; 291(16): 8309-23, 2016 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-26872972

RESUMEN

Heat shock protein 90 (HSP90) is a molecular chaperone that is up-regulated in cancer and is required for the folding of numerous signaling proteins. Consequently, HSP90 represents an ideal target for the development of new anti-cancer agents. The human HSP90 isoform, glucose-regulated protein 94 (GRP94), resides in the endoplasmic reticulum and regulates secretory pathways, integrins, and Toll-like receptors, which contribute to regulating immunity and metastasis. However, the cellular function of GRP94 remains underinvestigated. We report that GRP94 knockdown cells are defective in intracellular transport and, consequently, negatively impact the trafficking of F-actin toward the cellular cortex, integrin α2 and integrin αL toward the cell membrane and filopodia, and secretory vesicles containing the HSP90α-AHA1-survivin complex toward the leading edge. As a result, GRP94 knockdown cells form a multipolar spindle instead of bipolar morphology and consequently manifest a defect in cell migration and adhesion.


Asunto(s)
Movimiento Celular , Polaridad Celular , Proteínas HSP90 de Choque Térmico/metabolismo , Glicoproteínas de Membrana/metabolismo , Proteínas de Neoplasias/metabolismo , Neoplasias/metabolismo , Línea Celular Tumoral , Proteínas HSP90 de Choque Térmico/genética , Humanos , Cadenas alfa de Integrinas/genética , Cadenas alfa de Integrinas/metabolismo , Glicoproteínas de Membrana/genética , Proteínas de Neoplasias/genética , Neoplasias/genética , Neoplasias/patología , Transporte de Proteínas , Huso Acromático/genética , Huso Acromático/metabolismo
13.
Childs Nerv Syst ; 33(2): 329-335, 2017 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-27988879

RESUMEN

INTRODUCTION: Therapeutic hypothermia for the treatment of moderate to severe neonatal hypoxic ischemic encephalopathy has been shown to reduce death and disability, but the effects on seizures after discharge from the Neonatal ICU are not known. METHODS: A retrospective cohort study was conducted involving 56 neonates admitted to the Neonatal ICU at Children's Hospital of Orange County, CA from January 1, 2007 to September 1, 2013 with hypoxic ischemic encephalopathy who met criteria for selective brain cooling. Fifteen patients received supportive care. Forty-one patients received cooling, of whom 25 were included for analysis. Sixteen patients from the hypothermia group and 12 from the no hypothermia group developed clinical seizures while inpatient. Up to 6 months, four patients (16%) had continued seizures in the therapeutic hypothermia group compared to eight (53%) patients who did not receive hypothermia. DISCUSSION: Our study shows an association between therapeutic hypothermia and reduced seizures after discharge from the neonatal intensive care unit. The short duration of follow-up, 6 months, is a limitation of this study. Another limitation is its observational nature, where reasons for treatment selection and exclusions are unmeasurable confounding factors. Further studies are needed to determine long-term effects.


Asunto(s)
Hipotermia Inducida/métodos , Hipoxia-Isquemia Encefálica/complicaciones , Unidades de Cuidado Intensivo Neonatal , Alta del Paciente/estadística & datos numéricos , Convulsiones/complicaciones , Convulsiones/terapia , Preescolar , Estudios de Cohortes , Femenino , Humanos , Lactante , Recién Nacido , Masculino
14.
Mol Pharmacol ; 88(1): 121-30, 2015 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-25939977

RESUMEN

The 90-kDa heat-shock protein (Hsp90) assists in the proper folding of numerous mutated or overexpressed signal transduction proteins that are involved in cancer. Inhibiting Hsp90 consequently is an attractive strategy for cancer therapy as the concomitant degradation of multiple oncoproteins may lead to effective antineoplastic agents. Here we report a novel C-terminal Hsp90 inhibitor, designated KU675, that exhibits potent antiproliferative and cytotoxic activity along with client protein degradation without induction of the heat-shock response in both androgen-dependent and -independent prostate cancer cell lines. In addition, KU675 demonstrates direct inhibition of Hsp90 complexes as measured by the inhibition of luciferase refolding in prostate cancer cells. In direct binding studies, the internal fluorescence signal of KU675 was used to determine the binding affinity of KU675 to recombinant Hsp90α, Hsp90ß, and Hsc70 proteins. The binding affinity (Kd) for Hsp90α was determined to be 191 µM, whereas the Kd for Hsp90ß was 726 µM, demonstrating a preference for Hsp90α. Western blot experiments with four different prostate cancer cell lines treated with KU675 supported this selectivity by inducing the degradation of Hsp90α -: dependent client proteins. KU675 also displayed binding to Hsc70 with a Kd value at 76.3 µM, which was supported in cellular by lower levels of Hsc70-specific client proteins on Western blot analyses. Overall, these findings suggest that KU675 is an Hsp90 C-terminal inhibitor, as well as a dual inhibitor of Hsc70, and may have potential use for the treatment of cancer.


Asunto(s)
Antineoplásicos/farmacología , Cumarinas/farmacología , Proteínas del Choque Térmico HSC70/antagonistas & inhibidores , Proteínas HSP90 de Choque Térmico/antagonistas & inhibidores , Novobiocina/análogos & derivados , Compuestos de Fenilurea/farmacología , Neoplasias de la Próstata/metabolismo , Antineoplásicos/síntesis química , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Cumarinas/síntesis química , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Humanos , Masculino , Compuestos de Fenilurea/síntesis química , Unión Proteica
15.
PLoS Genet ; 7(11): e1002365, 2011 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-22125491

RESUMEN

The budding yeast spindle pole body (SPB) is anchored in the nuclear envelope so that it can simultaneously nucleate both nuclear and cytoplasmic microtubules. During SPB duplication, the newly formed SPB is inserted into the nuclear membrane. The mechanism of SPB insertion is poorly understood but likely involves the action of integral membrane proteins to mediate changes in the nuclear envelope itself, such as fusion of the inner and outer nuclear membranes. Analysis of the functional domains of the budding yeast SUN protein and SPB component Mps3 revealed that most regions are not essential for growth or SPB duplication under wild-type conditions. However, a novel dominant allele in the P-loop region, MPS3-G186K, displays defects in multiple steps in SPB duplication, including SPB insertion, indicating a previously unknown role for Mps3 in this step of SPB assembly. Characterization of the MPS3-G186K mutant by electron microscopy revealed severe over-proliferation of the inner nuclear membrane, which could be rescued by altering the characteristics of the nuclear envelope using both chemical and genetic methods. Lipid profiling revealed that cells lacking MPS3 contain abnormal amounts of certain types of polar and neutral lipids, and deletion or mutation of MPS3 can suppress growth defects associated with inhibition of sterol biosynthesis, suggesting that Mps3 directly affects lipid homeostasis. Therefore, we propose that Mps3 facilitates insertion of SPBs in the nuclear membrane by modulating nuclear envelope composition.


Asunto(s)
Puntos de Control de la Fase M del Ciclo Celular/genética , Proteínas de la Membrana/genética , Microtúbulos/genética , Proteínas Nucleares/genética , Proteínas de Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/genética , Alelos , Proliferación Celular , Homeostasis , Metabolismo de los Lípidos , Proteínas de la Membrana/metabolismo , Proteínas Mutantes/genética , Proteínas Mutantes/metabolismo , Membrana Nuclear/genética , Membrana Nuclear/metabolismo , Proteínas Nucleares/metabolismo , Estructura Terciaria de Proteína , Saccharomyces cerevisiae/metabolismo , Proteínas de Saccharomyces cerevisiae/metabolismo
16.
Org Lett ; 26(4): 792-797, 2024 Feb 02.
Artículo en Inglés | MEDLINE | ID: mdl-38252507

RESUMEN

In the present work, we demonstrate a regioselective [2 + 2 + 2] cyclotrimerization of 1,3-diynes catalyzed by Ni0 to provide hexasubstituted benzenes (HSBs). HSBs have significant applications as functional materials and pharmaceuticals. The present protocol exhibited remarkable versatility, transforming 1,3-diynes with diverse alkyl, aryl, and heterocyclic groups to the corresponding HSBs. With the help of control experiments and density functional theory (DFT), the mechanism of the reaction and the origin of regioselectivity were elucidated.

17.
Org Lett ; 26(15): 2987-2992, 2024 Apr 19.
Artículo en Inglés | MEDLINE | ID: mdl-38563803

RESUMEN

A regioselective coupling of ortho-heteroaryl anilines and 7-oxabenzonorbornadienes has been developed by leveraging free amine-directed redox-neutral Ru(II) catalysis. This protocol facilitates formal C-2 arylation of the indole moiety under mild conditions to offer valuable heterobiaryls in high yields. The reaction displays a broad substrate generality and scalability and retains efficacy in the presence of diverse pharmacophore scaffolds. Moreover, products bearing a free amine group were successfully employed in Mg(NTf2)2-catalyzed double Michael addition cascade, which led to the synthesis of intricate indole- and pyrrole-fused azaheterocycles.

18.
ACS Biomater Sci Eng ; 10(2): 1112-1127, 2024 02 12.
Artículo en Inglés | MEDLINE | ID: mdl-38163852

RESUMEN

Measurement of pH in living cells is a great and decisive factor for providing an early and accurate diagnosis factor. Along with this, the multimodal transverse and longitudinal relaxivity enhancement potentiality over single modality within a single platform in the magnetic resonance imaging (MRI) field is a very challenging issue for diagnostic purposes in the biomedical field of application. Therefore, this work aims to design a versatile platform by fabricating a novel nanoprobe through holmium- and manganese-ion doping in carbon quantum dots (Ho-Mn-CQDs), which can show nearly neutral intracellular pH sensing and MRI imaging at the same time. These manufactured Ho-Mn-CQDs acted as excellent pH sensors in the near-neutral range (4.01-8.01) with the linearity between 6.01 and 8.01, which could be useful for the intracellular pH-sensing capability. An innumerable number of carboxyl and amino groups are present on the surface of the prepared nanoprobe, making it an excellent candidate for pH sensing through fluorescence intensity quenching phenomena. Cellular uptake and cell viability experiments were also executed to affirm the intracellular accepting ability of Ho-Mn-CQDs. Furthermore, with this pH-sensing quality, these Ho-Mn-CQDs are also capable of acting as T1-T2 dual modal imaging contrast agents in comparison with pristine Ho-doped and Mn-doped CQDs. The Ho-Mn-CQDs showed an increment of r1 and r2 relaxivity values simultaneously compared with only the negative contrast agent, holmium in holmium-doped CQDs, and the positive contrast agent, manganese in manganese-doped CQDs. The above-mentioned observations elucidate that its tiny size, excitation dependence of fluorescence behavior, low cytotoxicity, and dual modal contrast imaging capability make it an ideal candidate for pH monitoring in the near-neutral range and also as a dual modal MRI imaging contrast enhancement nanoprobe at the same time.


Asunto(s)
Medios de Contraste , Manganeso , Carbono , Holmio , Concentración de Iones de Hidrógeno
19.
Pediatr Neurol ; 155: 133-140, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38640862

RESUMEN

BACKGROUND: Children with congenital heart disease (CHD) have a higher prevalence of motor impairment secondary to brain injury, resulting in cerebral palsy (CP). The purpose of this study is to determine the prevalence of CP in CHD in a single-center cohort, stratify risk based on surgical mortality using Society of Thoracic Surgeons-European Association for Cardio-Thoracic Surgery (STAT) categories and identify risk factors. METHODS: Retrospective cohort study of pediatric patients registered in the University of Florida (UF) Society of Thoracic Surgeons Congenital Heart Surgery database from 2006 to 2017 with a diagnosis of CHD who continued follow-up for more than two years at UF. RESULTS: A total of 701 children with CHD met inclusion criteria. Children identified to have CP were 54 (7.7%). Most common presentation was spastic hemiplegic CP with a Gross Motor Function Classification System of level 2. Analysis of surgical and intensive care factors between the two groups showed that children with CHD and CP had longer time from admission to surgery (P = 0.003), higher STAT categories 4 and 5 (P = 0.038), and higher frequency of brain injury and seizures (P < 0.001). Developmental disabilities and rehabilitation needs were significantly greater for children with CHD and CP when compared with those with CHD alone (P < 0.001). CONCLUSIONS: In our cohort, 7.7% children with CHD develop CP; this is significantly higher than the 2010 US population estimate of 0.3%. Our study suggests higher STAT categories, brain injury, and seizures are associated with developing CP in children with CHD.


Asunto(s)
Parálisis Cerebral , Cardiopatías Congénitas , Humanos , Parálisis Cerebral/epidemiología , Parálisis Cerebral/complicaciones , Parálisis Cerebral/etiología , Masculino , Femenino , Cardiopatías Congénitas/cirugía , Cardiopatías Congénitas/complicaciones , Cardiopatías Congénitas/mortalidad , Estudios Retrospectivos , Prevalencia , Factores de Riesgo , Lactante , Preescolar , Niño , Adolescente
20.
World Neurosurg ; 181: e809-e819, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37923012

RESUMEN

OBJECTIVE: Craniopharyngioma (CP) is a benign neuroepithelial tumor generally treated with maximal safe resection and radiation therapy (RT) in incompletely resected CP or in recurrent tumors to achieve long-term control. We analyzed the clinical outcomes of patients with CPs treated with a multimodality approach. PATIENTS AND METHODS: A retrospective clinical audit of histologically proven CPs registered between 2008 and 2019 at a specialized neuro-oncology center in India was performed. Time-to-event outcomes (overall survival [OS] and progression-free survival [PFS]) were analyzed. RESULTS: One hundred and twenty-two patients with CP were analyzed. The median age of the population was 14 years (interquartile range [IQR], 8-26) with a significant male preponderance. Gross total resection was achieved in only 25% of patients. At a median follow-up of 57.1 months (IQR, 27.8-87.8), 5-year estimates of PFS and OS were 52% (95% confidence interval, 46%-63.4%) and 85.8% (95% confidence interval, 78.6%-93%), respectively. Recurrence or progression was observed in 48 of 122 patients (39.3%) at a median time of 84.4 months (IQR, 24.7-174.8). On multivariate analysis, the absence of residual disease (P = 0.004), near-total resection (P = 0.035), and use of up-front adjuvant RT (P < 0.001) significantly improved the 5-year PFS, whereas the absence of extracavernous extension (P = 0.058) and any use of postoperative RT (P = 0.026) significantly improved the 5-year OS. CONCLUSIONS: This study represents one of the largest single-institutional series of CPs, showing improved PFS with up-front adjuvant RT in most cases of CP. Deferring adjuvant RT should be considered only in patients with no evidence of residual disease (as shown on dedicated sellar imaging) after primary surgery.


Asunto(s)
Craneofaringioma , Neoplasias Hipofisarias , Humanos , Masculino , Adolescente , Resultado del Tratamiento , Estudios Retrospectivos , Craneofaringioma/radioterapia , Craneofaringioma/cirugía , Neoplasias Hipofisarias/radioterapia , Neoplasias Hipofisarias/cirugía , Recurrencia Local de Neoplasia
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