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1.
J Am Chem Soc ; 146(19): 12889-12894, 2024 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-38690854

RESUMEN

We have successfully achieved selective and efficient functionalization of sheet edges in microcrystalline multilayer γ-graphyne through two methods: cross-coupling with residual bromide edge groups and copper-catalyzed azide-alkyne cycloaddition (CuAAC) with edge terminal alkyne groups. This modification significantly enhances the ease of mechanical exfoliation and dispersibility of the sheets of γ-graphyne. Specifically, C18-grafted γ-graphyne forms stable dispersions in compatible organic solvents, allowing for the imaging of atomically thin layers of γ-graphyne for the first time. Additionally, we have discovered that phenylacetylide edge groups alter the preferred stacking mode of γ-graphyne sheets. Few-layer flakes of Ph-edge γ-graphyne exhibit a preference for the R3m space group, contrasting with the aperiodic stacking of Br-edge γ-graphyne. These results open the door for scalable exfoliation of few-layer flakes of γ-graphyne with a high aspect ratio, enabling potential applications in carbon electronics.

2.
J Integr Neurosci ; 23(2): 43, 2024 Feb 20.
Artículo en Inglés | MEDLINE | ID: mdl-38419454

RESUMEN

In the initial assessment of a headache patient, several dangerous secondary etiologies must be considered. A thorough history and physical examination, along with a comprehensive differential diagnosis may alert a physician to the diagnosis of a secondary headache particularly when it is accompanied by certain clinical features. Evaluation and workup include a complete neurological examination, consideration of neuroimaging, and serum/spinal fluid analysis if indicated. Careful attention to the patients' history and physical examination will guide the diagnostic work-up and management. In this review, we summarize the diagnostic workup of various primary and secondary headache etiologies. Although most headaches are primary in nature, it is essential to screen for headache "red flags", as they can suggest life threatening secondary etiologies. When secondary causes are suspected, appropriate neuroimaging can further differentiate the underlying cause. The appropriate imaging is dependent on the most likely secondary etiology, which is deduced from history and physical examination. When no red flags are present, primary headaches are more likely. These can be differentiated by frequency, location, duration, triggers, and presence of aura. The different clinical presentations for secondary headaches, as well as the distinguishing features for primary headaches are outlined in this review.


Asunto(s)
Trastornos de Cefalalgia , Humanos , Cefalea/diagnóstico , Cefalea/etiología , Neuroimagen/efectos adversos , Diagnóstico Diferencial
3.
FASEB J ; 35(4): e21481, 2021 04.
Artículo en Inglés | MEDLINE | ID: mdl-33710668

RESUMEN

The midcycle luteinizing hormone (LH) surge initiates a cascade of events within the ovarian follicle which culminates in ovulation. Only mural granulosa cells and theca cells express large numbers of LH receptors, and LH-stimulated paracrine mediators communicate the ovulatory signal within the follicle. Recent reports identified the neuropeptide neurotensin (NTS) as a product of granulosa cells. Here, we demonstrate that granulosa cells were the primary site of NTS expression in macaque ovulatory follicles. Granulosa cell NTS mRNA and protein increased after human chorionic gonadotropin (hCG) administration, which substitutes for the LH surge. To identify ovulatory actions of NTS, a NTS-neutralizing antibody was injected into preovulatory macaque follicles. hCG administration immediately followed, and ovaries were removed 48 hours later to evaluate ovulatory events. Follicles injected with control IgG ovulated normally. In contrast, 75% of NTS antibody-injected follicles failed to ovulate, containing oocytes trapped within unruptured, hemorrhagic follicles. Serum progesterone was unchanged. Of the three NTS receptors, SORT1 was highly expressed in follicular granulosa, theca, and endothelial cells; NTSR1 and NTSR2 were expressed at lower levels. Excessive blood cells in NTS antibody-injected follicles indicated vascular anomalies, so the response of monkey ovarian endothelial cells to NTS was evaluated in vitro. NTS stimulated endothelial cell migration and capillary sprout formation, consistent with a role for NTS in vascular remodeling associated with ovulation. In summary, we identified NTS as a possible paracrine mediator of ovulation. Further investigation of the NTS synthesis/response pathway may lead to improved treatments for infertility and novel targets for contraception.


Asunto(s)
Células Endoteliales/metabolismo , Células de la Granulosa/metabolismo , Neurotensina/metabolismo , Ovario/metabolismo , Animales , Gonadotropina Coriónica/metabolismo , Femenino , Hormona Luteinizante/sangre , Oocitos/metabolismo , Folículo Ovárico/metabolismo , Ovulación/fisiología
4.
Artículo en Inglés | MEDLINE | ID: mdl-26260898

RESUMEN

Chickens selected for low (LWS) and high (HWS) juvenile body weight (BW) for 55 generations differ in BW by 10-fold at selection age. High (HWR) and low (LWR) body weight-relaxed lines have been random-bred since the 46th generation. Our objective was to evaluate the developmental and nutritional regulation of pancreatic mRNA abundance of pancreatic and duodenal homeobox 1 (PDX1), preproinsulin (PPI), preproglucagon (PPG), and glucose transporter 2 (GLUT2). At day of hatch (DOH) and days 1, 3, 7, and 15 (D1, 3, 7 and 15, respectively), pancreas was collected and real time PCR was performed in Experiment 1. In Experiment 2, HWS and LWS were fed or delayed access to food for 72 h post-hatch, and pancreas collected at D15. There was an interaction of line and age for GLUT2 (P=0.001), PPI (P<0.0001), PPG (P=0.034), and PDX1 (P<0.0001). Expression was greater in chicks from LWR and LWS than HWR and HWS. There was an interaction of line and nutrition on PPG (P<0.0001) and GLUT2 (P=0.001) mRNA, where expression was similar among chicks that were fed but greater in LWS than HWS when chicks were delayed access to food. Thus, the first two weeks is important for maturation of pancreatic endocrine function. Long-term selection for BW is associated with differences in pancreas development, and delaying access to food at hatch may have persisting effects on glucose regulatory function.


Asunto(s)
Proteínas Aviares/genética , Peso Corporal/genética , Pollos/genética , Regulación del Desarrollo de la Expresión Génica , Glucagón/genética , Transportador de Glucosa de Tipo 2/genética , Fenómenos Fisiológicos Nutricionales de los Animales , Animales , Animales Recién Nacidos , Cruzamiento , Pollos/crecimiento & desarrollo , Femenino , Alimentos , Masculino , Páncreas/metabolismo , ARN Mensajero/genética , ARN Mensajero/metabolismo , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Selección Genética , Factores de Tiempo , Regulación hacia Arriba/genética
5.
Front Immunol ; 13: 752315, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35222367

RESUMEN

The EPICC peptides are a family of peptides that have been developed from the sequence of the capsid protein of human astrovirus type 1 and previously shown to inhibit the classical and lectin pathways of complement. The EPICC peptides have been further optimized to increase aqueous solubility and identify additional mechanisms of action. Our laboratory has developed the lead EPICC molecule, PA-dPEG24 (also known as RLS-0071), which is composed of a 15 amino acid peptide with a C-terminal monodisperse 24-mer PEGylated moiety. RLS-0071 has been demonstrated to possess other mechanisms of action in addition to complement blockade that include the inhibition of neutrophil-driven myeloperoxidase (MPO) activity, inhibition of neutrophil extracellular trap (NET) formation as well as intrinsic antioxidant activity mediated by vicinal cysteine residues contained within the peptide sequence. RLS-0071 has been tested in various ex vivo and in vivo systems and has shown promise for the treatment of both immune-mediated hematological diseases where alterations in the classical complement pathway plays an important pathogenic role as well as in models of tissue-based diseases such as acute lung injury and hypoxic ischemic encephalopathy driven by both complement and neutrophil-mediated pathways (i.e., MPO activity and NET formation). Next generation EPICC peptides containing a sarcosine residue substitution in various positions within the peptide sequence possess aqueous solubility in the absence of PEGylation and demonstrate enhanced complement and neutrophil inhibitory activity compared to RLS-0071. This review details the development of the EPICC peptides, elucidation of their dual-acting complement and neutrophil inhibitory activities and efficacy in ex vivo systems using human clinical specimens and in vivo efficacy in animal disease models.


Asunto(s)
Trampas Extracelulares , Péptidos , Secuencia de Aminoácidos , Animales , Antiinflamatorios/farmacología , Antiinflamatorios/uso terapéutico , Vía Clásica del Complemento , Trampas Extracelulares/metabolismo , Péptidos/metabolismo , Agua
6.
G3 (Bethesda) ; 10(3): 1087-1098, 2020 03 05.
Artículo en Inglés | MEDLINE | ID: mdl-31969430

RESUMEN

Limited lifespan and senescence are near-universal phenomena. These quantitative traits exhibit variation in natural populations due to the segregation of many interacting loci and from environmental effects. Due to the complexity of the genetic control of lifespan and senescence, our understanding of the genetic basis of variation in these traits is incomplete. Here, we analyzed the pattern of genetic divergence between long-lived (O) Drosophila melanogaster lines selected for postponed reproductive senescence and unselected control (B) lines. We quantified the productivity of the O and B lines and found that reproductive senescence is maternally controlled. We therefore chose 57 candidate genes that are expressed in ovaries, 49 of which have human orthologs, and assessed the effects of RNA interference in ovaries and accessary glands on lifespan and reproduction. All but one candidate gene affected at least one life history trait in one sex or productivity week. In addition, 23 genes had antagonistic pleiotropic effects on lifespan and productivity. Identifying evolutionarily conserved genes affecting increased lifespan and delayed reproductive senescence is the first step toward understanding the evolutionary forces that maintain segregating variation at these loci in nature and may provide potential targets for therapeutic intervention to delay senescence while increasing lifespan.


Asunto(s)
Envejecimiento/genética , Drosophila melanogaster/genética , Longevidad/genética , Animales , Femenino , Expresión Génica , Genes de Insecto , Masculino , Ovario/metabolismo , Interferencia de ARN , Reproducción/genética
7.
J Multidiscip Healthc ; 10: 271-276, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28860794

RESUMEN

This paper presents the findings from a national survey which the University of Washington conducted among leaders of 32 US academic nursing institutions that are part of academic health centers (AHCs) and complements these findings with results from a separate report by the American Association of Colleges of Nursing. While expressing overall satisfaction with their AHC relationships, these leaders find that nursing is often given greater parity in matters of education and research than in mission setting, financial, and governance matters. AHCs are being asked to meet new health care challenges in new ways, starting with the education of health care professionals. AHCs need to be restructured to give nursing full parity if the nation's and world's needs for preventive and clinical care are to be best met.

8.
Qual Manag Health Care ; 24(1): 45-51, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-25539490

RESUMEN

In an environment where there is increased demand for hospital beds, it is important that inpatient flow from admission to treatment to discharge is optimized. Among the many drivers that impact efficient patient throughput is an effective and timely discharge process. Early morning discharge helps align inpatient capacity with clinical demand, thereby avoiding gridlock that adversely affects scheduled surgical procedures, diagnostic procedures, and therapies. At our large, academic medical center, we hypothesized that an interdisciplinary approach to scheduled discharge order entry would increase the percentage of discharges occurring before 11:00 AM and improve overall discharge time. The pilot study involved moving rate-limiting steps to earlier in the discharge process, specifically medication reconciliation to the night before discharge and "discharge to home" order entry before 9:00 AM the morning of discharge. The baseline rate of discharges before 11:00 AM was 8% and significantly increased to 11% after the intervention (P = .02). Moreover, in the subset of patients (21%) for whom early medication reconciliation and discharge to home order entry were both executed, the percentage of patient discharges occurring before 11:00 AM increased to 29.7%, with an associated average discharge time of more than 3 hours earlier. No patient harm events were associated with this pilot project. There was no significant change in length of stay, and 30-day readmission rate improved significantly from 13.8% to 10.3% (P = .002). Our study demonstrates that a multidisciplinary approach using prescribed order entry and medication reconciliation is a low cost, safe, and effective way to increase early morning discharges and improve patient flow for large hospitals with high volumes of scheduled patient admissions.


Asunto(s)
Centros Médicos Académicos/organización & administración , Continuidad de la Atención al Paciente/organización & administración , Relaciones Interprofesionales , Alta del Paciente , Lista de Verificación , Eficiencia Organizacional , Hospitales con 300 a 499 Camas , Humanos , Tiempo de Internación , Conciliación de Medicamentos/organización & administración , Readmisión del Paciente , Proyectos Piloto
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