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1.
J Lipid Res ; 65(3): 100512, 2024 03.
Artículo en Inglés | MEDLINE | ID: mdl-38295986

RESUMEN

Ebola virus (EBOV) causes severe hemorrhagic fever in humans and is lethal in a large percentage of those infected. The EBOV matrix protein viral protein 40 kDa (VP40) is a peripheral binding protein that forms a shell beneath the lipid bilayer in virions and virus-like particles (VLPs). VP40 is required for virus assembly and budding from the host cell plasma membrane. VP40 is a dimer that can rearrange into oligomers at the plasma membrane interface, but it is unclear how these structures form and how they are stabilized. We therefore investigated the ability of VP40 to form stable oligomers using in vitro and cellular assays. We characterized two lysine-rich regions in the VP40 C-terminal domain (CTD) that bind phosphatidylinositol-4,5-bisphosphate (PI(4,5)P2) and play distinct roles in lipid binding and the assembly of the EBOV matrix layer. The extensive analysis of VP40 with and without lipids by hydrogen deuterium exchange mass spectrometry revealed that VP40 oligomers become extremely stable when VP40 binds PI(4,5)P2. The PI(4,5)P2-induced stability of VP40 dimers and oligomers is a critical factor in VP40 oligomerization and release of VLPs from the plasma membrane. The two lysine-rich regions of the VP40 CTD have different roles with respect to interactions with plasma membrane phosphatidylserine (PS) and PI(4,5)P2. CTD region 1 (Lys221, Lys224, and Lys225) interacts with PI(4,5)P2 more favorably than PS and is important for VP40 extent of oligomerization. In contrast, region 2 (Lys270, Lys274, Lys275, and Lys279) mediates VP40 oligomer stability via lipid interactions and has a more prominent role in release of VLPs.


Asunto(s)
Ebolavirus , Fiebre Hemorrágica Ebola , Humanos , Ebolavirus/metabolismo , Fiebre Hemorrágica Ebola/metabolismo , Lisina/metabolismo , Sitios de Unión , Lípidos , Unión Proteica
2.
Ann Rheum Dis ; 82(2): 262-271, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-36109140

RESUMEN

OBJECTIVES: Osteoarthritis (OA) features ageing-related defects in cellular homeostasis mechanisms in articular cartilage. These defects are associated with suppression of forkhead box O (FoxO) transcription factors. FoxO1 or FoxO3 deficient mice show early onset OA while FoxO1 protects against oxidative stress in chondrocytes and promotes expression of autophagy genes and the essential joint lubricant proteoglycan 4 (PRG4). The objective of this study was to identify small molecules that can increase FoxO1 expression. METHODS: We constructed a reporter cell line with FoxO1 promoter sequences and performed high-throughput screening (HTS) of the Repurposing, Focused Rescue and Accelerated Medchem (ReFRAME) library . Hits from the HTS were validated and function was assessed in human chondrocytes, meniscus cells and synoviocytes and following administration to mice. The most promising hit, the histone deacetylase inhibitor (HDACI) panobinostat was tested in a murine OA model. RESULTS: Among the top hits were HDACI and testing in human chondrocytes, meniscus cells and synoviocytes showed that panobinostat was the most promising compound as it increased the expression of autophagy genes and PRG4 while suppressing the basal and IL-1ß induced expression of inflammatory mediators and extracellular matrix degrading enzymes. Intraperitoneal administration of panobinostat also suppressed the expression of mediators of OA pathogenesis induced by intra-articular injection of IL-1ß. In a murine OA model, panobinostat reduced the severity of histological changes in cartilage, synovium and subchondral bone and improved pain behaviours. CONCLUSION: Panobinostat has a clinically relevant activity profile and is a candidate for OA symptom and structure modification.


Asunto(s)
Cartílago Articular , Osteoartritis , Humanos , Ratones , Animales , Factores de Transcripción Forkhead , Inhibidores de Histona Desacetilasas/metabolismo , Panobinostat/metabolismo , Osteoartritis/patología , Envejecimiento , Condrocitos/metabolismo , Cartílago Articular/metabolismo , Interleucina-1beta/metabolismo
3.
Health Promot Pract ; 24(1_suppl): 125S-127S, 2023 05.
Artículo en Inglés | MEDLINE | ID: mdl-36999492

RESUMEN

Rural residents tend to eat less fruits and vegetables, placing them at higher risk of chronic diseases compared with urban residents. Farmers' markets can provide increased access to fresh produce for rural communities. Encouraging markets to accept Supplemental Nutrition Assistance Program (SNAP) benefits through Electronic Benefit Transfer (EBT) can expand access to healthy foods to low-income residents. Rural markets are less likely to accept SNAP compared with urban markets. Rural producers have identified lack of knowledge and limited support about the application process as barriers for accepting SNAP. This case study details how our Extension program helped a rural producer through the SNAP application process. We started with a workshop to inform rural producers about the benefits of accepting SNAP. After the workshop, we provided hands-on support and assistance to help one producer navigate the EBT application process as well as how to implement and advertise SNAP at the market. Implications for practitioners about tips to help producers overcome challenges and barriers for EBT acceptance are discussed.


Asunto(s)
Agricultores , Asistencia Alimentaria , Humanos , Tennessee , Población Rural , Abastecimiento de Alimentos , Frutas , Verduras
4.
Glia ; 70(7): 1337-1358, 2022 07.
Artículo en Inglés | MEDLINE | ID: mdl-35373853

RESUMEN

Survival motor neuron (SMN) protein deficiency results in loss of alpha motor neurons and subsequent muscle atrophy in patients with spinal muscular atrophy (SMA). Reactive microglia have been reported in SMA mice and depleting microglia rescues the number of proprioceptive synapses, suggesting a role in SMA pathology. Here, we explore the contribution of lymphocytes on microglia reactivity in SMA mice and investigate how SMN deficiency alters the reactive profile of human induced pluripotent stem cell (iPSC)-derived microglia. We show that microglia adopt a reactive morphology in spinal cords of SMA mice. Ablating lymphocytes did not alter the reactive morphology of SMA microglia and did not improve the survival or motor function of SMA mice, indicating limited impact of peripheral immune cells on the SMA phenotype. We found iPSC-derived SMA microglia adopted an amoeboid morphology and displayed a reactive transcriptome profile, increased cell migration, and enhanced phagocytic activity. Importantly, cell morphology and electrophysiological properties of motor neurons were altered when they were incubated with conditioned media from SMA microglia. Together, these data reveal that SMN-deficient microglia adopt a reactive profile and exhibit an exaggerated inflammatory response with potential impact on SMA neuropathology.


Asunto(s)
Células Madre Pluripotentes Inducidas , Atrofia Muscular Espinal , Deficiencia de Proteína , Animales , Modelos Animales de Enfermedad , Humanos , Células Madre Pluripotentes Inducidas/metabolismo , Ratones , Microglía/metabolismo , Neuronas Motoras/patología , Atrofia Muscular Espinal/genética , Atrofia Muscular Espinal/metabolismo , Atrofia Muscular Espinal/patología , Deficiencia de Proteína/metabolismo , Deficiencia de Proteína/patología , Proteína 1 para la Supervivencia de la Neurona Motora/genética , Proteína 1 para la Supervivencia de la Neurona Motora/metabolismo
5.
Chembiochem ; 23(9): e202200012, 2022 05 04.
Artículo en Inglés | MEDLINE | ID: mdl-35235240

RESUMEN

Small-molecule splicing modulators exemplified by an FDA-approved drug, risdiplam, are a new pharmacological modality for regulating the expression and stability of splice isoforms. We report a CRISPR-mediated enzyme fragment complementation (EFC) assay to quantify the splice isoform stability. The EFC assay harnessed a 42 amino acid split of a ß-galactosidase (designate α-tag), which could be fused at the termini of the target genes using CRISPR/cas9. The α-tagged splice isoform would be quantified by measuring the enzymatic activity upon complementation with the rest of ß-galactosidase. This EFC assay retained all the sequences of introns and exons of the target gene in the native genomic environment that recapitulates the cell biology of the diseases of interest. For a proof-of-concept, we developed a CRISPR-mediated EFC assay targeting the exon 7 of the survival of motor neuron 2 (SMN2) gene. The EFC assay is compatible with 384-well plates and robustly quantified the splicing modulation activity of small molecules. In this study, we also discovered that a coumarin derivative, compound 4, potently modulated SMN2 exon 7 splicing at as low as 1.1 nM.


Asunto(s)
Pruebas de Enzimas , Exones/genética , Mutación , Isoformas de Proteínas , beta-Galactosidasa
6.
Bioorg Med Chem Lett ; 60: 128571, 2022 03 15.
Artículo en Inglés | MEDLINE | ID: mdl-35065233

RESUMEN

In immunoglobulin light chain (LC) amyloidosis, the misfolding, or misfolding and misassembly of LC a protein or fragments thereof resulting from aberrant endoproteolysis, causes organ damage to patients. A small molecule "kinetic stabilizer" drug could slow or stop these processes and improve prognosis. We previously identified coumarin-based kinetic stabilizers of LCs that can be divided into four components, including a "linker module" and "distal substructure". Our prior studies focused on characterizing carbamate, hydantoin, and spirocyclic urea linker modules, which bind in a solvent-exposed site at the VL-VL domain interface of the LC dimer. Here, we report structure-activity relationship data on 7-diethylamino coumarin-based kinetic stabilizers. This substructure occupies the previously characterized "anchor cavity" and the "aromatic slit". The potencies of amide and urea linker modules terminating in a variety of distal substructures attached at the 3-position of this coumarin ring were assessed. Surprisingly, crystallographic data on a 7-diethylamino coumarin-based kinetic stabilizer reveals that the urea linker module and distal substructure attached at the 3-position bind a solvent-exposed region of the full-length LC dimer distinct from previously characterized sites. Our results further elaborate the small-molecule binding surface of LCs that could be occupied by potent and selective LC kinetic stabilizers.


Asunto(s)
Cumarinas/farmacología , Cadenas Ligeras de Inmunoglobulina/química , Urea/química , Sitios de Unión/efectos de los fármacos , Cumarinas/síntesis química , Cumarinas/química , Relación Dosis-Respuesta a Droga , Humanos , Cinética , Estructura Molecular , Estabilidad Proteica , Relación Estructura-Actividad
7.
Mult Scler ; 27(5): 742-754, 2021 04.
Artículo en Inglés | MEDLINE | ID: mdl-32672101

RESUMEN

BACKGROUND: Relapsing-remitting multiple sclerosis (RRMS) usually evolves into secondary progressive multiple sclerosis (SPMS). Recognition of SPMS is important because of prognostic and treatment implications. OBJECTIVE: The objective of this study is to determine distributions of patient-reported outcomes (PROs) and the Timed 25-Foot Walk (T25FW) at SPMS diagnosis and describe the evolution of these metrics in patients with SPMS. METHODS: A tertiary MS center clinical database was queried to identify patients with RRMS and SPMS. PRO data including performance scales (PS), Patient Health Questionnaire-9 (PHQ-9), European Quality of Life-5-Dimensions (EQ-5D), and the T25FW were extracted. Descriptive statistics were calculated at SPMS diagnosis, and score trajectories were modeled. Cox proportional hazards modeling was used to estimate hazard ratios for time to SPMS diagnosis. RESULTS: Among 5,558 patients identified, 164 were diagnosed with SPMS between January 2008 and June 2016. At SPMS diagnosis, the mean outcome values were T25FW = 12.5 seconds (standard deviation, SD = 10.7), PS = 15.6 (SD = 6.5), PHQ-9 = 6.8 (SD = 4.2), and EQ-5D = 0.63 (SD = 0.20). Distinct patterns were observed in the measures leading up to SPMS diagnosis. Higher age, male gender, longer disease duration, and greater disability were associated with an increased hazard of SPMS diagnosis. CONCLUSION: Longitudinal monitoring of PROs and performance metrics may help identify those at higher risk of near-term SPMS.


Asunto(s)
Esclerosis Múltiple Crónica Progresiva , Esclerosis Múltiple Recurrente-Remitente , Esclerosis Múltiple , Benchmarking , Progresión de la Enfermedad , Humanos , Masculino , Esclerosis Múltiple Crónica Progresiva/diagnóstico , Esclerosis Múltiple Recurrente-Remitente/diagnóstico , Medición de Resultados Informados por el Paciente , Calidad de Vida
8.
Am J Public Health ; 111(S3): S215-S223, 2021 10.
Artículo en Inglés | MEDLINE | ID: mdl-34709876

RESUMEN

Public Health 3.0 approaches are critical for monitoring disparities in economic, social, and overall health impacts following the COVID-19 pandemic and its associated policy changes to slow community spread. Timely, cross-sector data as identified using this approach help decisionmakers identify changes, track racial disparities, and address unintended consequences during a pandemic. We applied a monitoring and evaluation framework that combined policy changes with timely, relevant cross-sector data and community review. Indicators covered unemployment, basic needs, family violence, education, childcare, access to health care, and mental, physical, and behavioral health. In response to increasing COVID-19 cases, nonpharmaceutical intervention strategies were implemented in March 2020 in King County, Washington. By December 2020, 554 000 unemployment claims were filed. Social service calls increased 100%, behavioral health crisis calls increased 25%, and domestic violence calls increased 25%, with disproportionate impact on communities of color. This framework can be replicated by local jurisdictions to inform and address racial inequities in ongoing COVID-19 mitigation and recovery. Cross-sector collaboration between public health and sectors addressing the social determinants of health are an essential first step to have an impact on long-standing racial inequities. (Am J Public Health. 2021;111(S3):S215-S223. https://doi.org/10.2105/AJPH.2021.306422).


Asunto(s)
COVID-19 , Política de Salud , Accesibilidad a los Servicios de Salud , Disparidades en el Estado de Salud , Salud Pública , COVID-19/economía , COVID-19/prevención & control , Humanos , Salud Mental , Vigilancia de la Población , Desempleo/estadística & datos numéricos , Washingtón
9.
Arch Phys Med Rehabil ; 102(5): 865-873, 2021 05.
Artículo en Inglés | MEDLINE | ID: mdl-33278365

RESUMEN

OBJECTIVES: To investigate whether the urogenital and bowel functional gains previously demonstrated post-locomotor step training after chronic spinal cord injury could have been derived due to weight-bearing alone or from exercise in general. DESIGN: Prospective cohort study; pilot trial with small sample size. SETTING: Urogenital and bowel scientific core facility at a rehabilitation institute and spinal cord injury research center in the United States. PARTICIPANTS: Men and women (N=22) with spinal cord injury (American Spinal Injury Association Impairment Scale grades of A-D) participated in this study. INTERVENTIONS: Approximately 80 daily 1-hour sessions of either stand training or nonweight-bearing arm crank ergometry. Comparisons were made with previously published locomotor training data (step; N=7). MAIN OUTCOME MEASURES: Assessments at both pre- and post-training timepoints included cystometry for bladder function and International Data Set Questionnaires for bowel and sexual functions. RESULTS: Cystometry measurements revealed a significant decrease in bladder pressure and limited improvement in compliance with nonweight-bearing exercise but not with standing. Although International Data Set questionnaires revealed profound bowel dysfunction and marked deficits in sexual function pretraining, no differences were identified poststand or after nonweight-bearing exercise. CONCLUSIONS: These pilot trial results suggest that, although stand and weight-bearing alone do not benefit pelvic organ functions after spinal cord injury, exercise in general may contribute at least partially to the lowering of bladder pressure and the increase in compliance that was seen previously with locomotor training, potentially through metabolic, humoral, and/or cardiovascular mechanisms. Thus, to maximize activity-based recovery training benefits for functions related to storage and emptying, an appropriate level of sensory input to the spinal cord neural circuitries controlling bladder and bowel requires task-specific stepping.


Asunto(s)
Terapia por Ejercicio/métodos , Intestino Neurogénico/rehabilitación , Disfunciones Sexuales Fisiológicas/rehabilitación , Traumatismos de la Médula Espinal/rehabilitación , Vejiga Urinaria Neurogénica/rehabilitación , Adulto , Estudios de Cohortes , Femenino , Humanos , Masculino , Persona de Mediana Edad , Proyectos Piloto , Estudios Prospectivos , Recuperación de la Función , Encuestas y Cuestionarios , Adulto Joven
10.
Proc Natl Acad Sci U S A ; 115(20): E4604-E4612, 2018 05 15.
Artículo en Inglés | MEDLINE | ID: mdl-29712837

RESUMEN

RG-7916 is a first-in-class drug candidate for the treatment of spinal muscular atrophy (SMA) that functions by modulating pre-mRNA splicing of the SMN2 gene, resulting in a 2.5-fold increase in survival of motor neuron (SMN) protein level, a key protein lacking in SMA patients. RG-7916 is currently in three interventional phase 2 clinical trials for various types of SMA. In this report, we show that SMN-C2 and -C3, close analogs of RG-7916, act as selective RNA-binding ligands that modulate pre-mRNA splicing. Chemical proteomic and genomic techniques reveal that SMN-C2 directly binds to the AGGAAG motif on exon 7 of the SMN2 pre-mRNA, and promotes a conformational change in two to three unpaired nucleotides at the junction of intron 6 and exon 7 in both in vitro and in-cell models. This change creates a new functional binding surface that increases binding of the splicing modulators, far upstream element binding protein 1 (FUBP1) and its homolog, KH-type splicing regulatory protein (KHSRP), to the SMN-C2/C3-SMN2 pre-mRNA complex and enhances SMN2 splicing. These findings underscore the potential of small-molecule drugs to selectively bind RNA and modulate pre-mRNA splicing as an approach to the treatment of human disease.


Asunto(s)
Empalme Alternativo , ADN Helicasas/genética , Proteínas de Unión al ADN/genética , Atrofia Muscular Espinal/genética , Precursores del ARN/genética , Proteínas de Unión al ARN/genética , Bibliotecas de Moléculas Pequeñas/farmacología , Transactivadores/genética , ADN Helicasas/química , ADN Helicasas/metabolismo , Proteínas de Unión al ADN/química , Proteínas de Unión al ADN/metabolismo , Exones , Humanos , Atrofia Muscular Espinal/metabolismo , Atrofia Muscular Espinal/patología , Conformación de Ácido Nucleico , Proteómica , Proteínas de Unión al ARN/química , Proteínas de Unión al ARN/metabolismo , Proteína 2 para la Supervivencia de la Neurona Motora/química , Proteína 2 para la Supervivencia de la Neurona Motora/genética , Proteína 2 para la Supervivencia de la Neurona Motora/metabolismo , Transactivadores/química , Transactivadores/metabolismo
11.
J Biol Chem ; 294(46): 17289-17300, 2019 11 15.
Artículo en Inglés | MEDLINE | ID: mdl-31597703

RESUMEN

Recent studies using two cholesterol-binding bacterial toxin proteins, perfringolysin O (PFO) and domain 4 of anthrolysin O (ALOD4), have shown that cholesterol in the plasma membranes (PMs) of animal cells resides in three distinct pools. The first pool comprises mobile cholesterol, accessible to both PFO and ALOD4, that is rapidly transported to the endoplasmic reticulum (ER) to signal cholesterol excess and maintain cholesterol homeostasis. The second is a sphingomyelin (SM)-sequestered pool inaccessible to PFO and ALOD4 but that becomes accessible by treatment with SM-degrading sphingomyelinase (SMase). The third is an essential pool also inaccessible to PFO and ALOD4 that cannot be liberated by SMase treatment. The accessible cholesterol pool can be trapped on PMs of live cells by nonlytic ALOD4, blocking its transport to the ER. However, studies of the two other pools have been hampered by a lack of available tools. Here, we used ostreolysin A (OlyA), which specifically binds SM/cholesterol complexes in membranes, to study the SM-sequestered cholesterol pool. Binding of nonlytic OlyA to SM/cholesterol complexes in PMs of live cells depleted the accessible PM cholesterol pool detectable by ALOD4. Consequently, transport of accessible cholesterol from PM to ER ceased, thereby activating SREBP transcription factors and increasing cholesterol synthesis. Thus, OlyA and ALOD4 both control movement of PM cholesterol, but through different lipid-binding mechanisms. We also found that PM-bound OlyA was rapidly internalized into cells, whereas PM-bound ALOD4 remained on the cell surface. Our findings establish OlyA and ALOD4 as complementary tools to investigate cellular cholesterol transport.


Asunto(s)
Proteínas Bacterianas/genética , Toxinas Bacterianas/genética , Colesterol/genética , Proteínas Hemolisinas/genética , Glicoproteínas de Membrana/genética , Animales , Proteínas Bacterianas/química , Toxinas Bacterianas/química , Toxinas Bacterianas/metabolismo , Transporte Biológico/genética , Células CHO , Membrana Celular/genética , Membrana Celular/metabolismo , Colesterol/biosíntesis , Colesterol/metabolismo , Cricetinae , Cricetulus , Retículo Endoplásmico/metabolismo , Proteínas Fúngicas/química , Proteínas Fúngicas/genética , Proteínas Hemolisinas/química , Proteínas Hemolisinas/metabolismo , Homeostasis , Metabolismo de los Lípidos/genética , Espectrometría de Masas , Glicoproteínas de Membrana/química , Esfingomielina Fosfodiesterasa/química , Esfingomielina Fosfodiesterasa/genética , Esfingomielinas/genética , Esfingomielinas/metabolismo , Proteínas de Unión a los Elementos Reguladores de Esteroles/genética
12.
J Biol Chem ; 294(2): 502-519, 2019 01 11.
Artículo en Inglés | MEDLINE | ID: mdl-30420430

RESUMEN

Formation of membrane pores/channels regulates various cellular processes, such as necroptosis or stem cell niche signaling. However, the roles of membrane lipids in the formation of pores and their biological functions are largely unknown. Here, using the cellular stress model evoked by the sphingolipid analog drug FTY720, we show that formation of ceramide-enriched membrane pores, referred to here as ceramidosomes, is initiated by a receptor-interacting Ser/Thr kinase 1 (RIPK1)-ceramide complex transported to the plasma membrane by nonmuscle myosin IIA-dependent trafficking in human lung cancer cells. Molecular modeling/simulation coupled with site-directed mutagenesis revealed that Asp147 or Asn169 of RIPK1 are key for ceramide binding and that Arg258 or Leu293 residues are involved in the myosin IIA interaction, leading to ceramidosome formation and necroptosis. Moreover, generation of ceramidosomes independently of any external drug/stress stimuli was also detected in the plasma membrane of germ line stem cells in ovaries during the early stages of oogenesis in Drosophila melanogaster Inhibition of ceramidosome formation via myosin IIA silencing limited germ line stem cell signaling and abrogated oogenesis. In conclusion, our findings indicate that the RIPK1-ceramide complex forms large membrane pores we named ceramidosomes. They further suggest that, in addition to their roles in stress-mediated necroptosis, these ceramide-enriched pores also regulate membrane integrity and signaling and might also play a role in D. melanogaster ovary development.


Asunto(s)
Membrana Celular/metabolismo , Ceramidas/metabolismo , Neoplasias Pulmonares/metabolismo , Proteínas Motoras Moleculares/metabolismo , Cadenas Pesadas de Miosina/metabolismo , Necrosis/metabolismo , Proteína Serina-Treonina Quinasas de Interacción con Receptores/metabolismo , Células A549 , Animales , Línea Celular , Membrana Celular/patología , Drosophila melanogaster/crecimiento & desarrollo , Femenino , Humanos , Neoplasias Pulmonares/patología , Simulación del Acoplamiento Molecular , Necrosis/patología , Oogénesis , Ovario/crecimiento & desarrollo
13.
Plant Cell ; 29(6): 1388-1405, 2017 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-28584166

RESUMEN

During cytokinesis in plants, trans-Golgi network-derived vesicles accumulate at the center of dividing cells and undergo various structural changes to give rise to the planar cell plate. However, how this conversion occurs at the molecular level remains elusive. In this study, we report that SH3 Domain-Containing Protein 2 (SH3P2) in Arabidopsis thaliana plays a crucial role in converting vesicles to the planar cell plate. SH3P2 RNAi plants showed cytokinesis-defective phenotypes and produced aggregations of vesicles at the leading edge of the cell plate. SH3P2 localized to the leading edge of the cell plate, particularly the constricted or curved regions of the cell plate. The BAR domain of SH3P2 induced tubulation of vesicles. SH3P2 formed a complex with dynamin-related protein 1A (DRP1A) and affected DRP1A accumulation to the cell plate. Based on these results, we propose that SH3P2 functions together with DRP1A to convert the fused vesicles to tubular structures during cytokinesis.


Asunto(s)
Proteínas de Arabidopsis/metabolismo , Arabidopsis/citología , Arabidopsis/metabolismo , Proteínas Portadoras/metabolismo , Arabidopsis/genética , Proteínas de Arabidopsis/genética , Proteínas Portadoras/genética , Citocinesis/genética , Citocinesis/fisiología , Dinaminas/genética , Dinaminas/metabolismo , Plantas Modificadas Genéticamente/citología , Plantas Modificadas Genéticamente/genética , Plantas Modificadas Genéticamente/metabolismo , Red trans-Golgi/metabolismo , Red trans-Golgi/fisiología
14.
J Immunol ; 200(5): 1671-1681, 2018 03 01.
Artículo en Inglés | MEDLINE | ID: mdl-29374074

RESUMEN

CD22 (Siglec-2) is a critical regulator of B cell activation and survival. CD22-/- mice generate significantly impaired Ab responses to T cell-independent type 2 (TI-2) Ags, including haptenated Ficoll and pneumococcal polysaccharides, Ags that elicit poor T cell help and activate BCR signaling via multivalent epitope crosslinking. This has been proposed to be due to impaired marginal zone (MZ) B cell development/maintenance in CD22-/- mice. However, mice expressing a mutant form of CD22 unable to bind sialic acid ligands generated normal TI-2 Ab responses, despite significantly reduced MZ B cells. Moreover, mice treated with CD22 ligand-binding blocking mAbs, which deplete MZ B cells, had little effect on TI-2 Ab responses. We therefore investigated the effects of CD22 deficiency on B-1b cells, an innate-like B cell population that plays a key role in TI-2 Ab responses. B-1b cells from CD22-/- mice had impaired BCR-induced proliferation and significantly increased intracellular Ca2+ concentration responses following BCR crosslinking. Ag-specific B-1b cell expansion and plasmablast differentiation following TI-2 Ag immunization was significantly impaired in CD22-/- mice, consistent with reduced TI-2 Ab responses. We generated CD22-/- mice with reduced CD19 levels (CD22-/-CD19+/-) to test the hypothesis that augmented B-1b cell BCR signaling in CD22-/- mice contributes to impaired TI-2 Ab responses. BCR-induced proliferation and intracellular Ca2+ concentration responses were normalized in CD22-/-CD19+/- B-1b cells. Consistent with this, TI-2 Ag-specific B-1b cell expansion, plasmablast differentiation, survival, and Ab responses were rescued in CD22-/-CD19+/- mice. Thus, CD22 plays a critical role in regulating TI-2 Ab responses through regulating B-1b cell signaling thresholds.


Asunto(s)
Antígenos T-Independientes/inmunología , Linfocitos B/inmunología , Lectina 2 Similar a Ig de Unión al Ácido Siálico/inmunología , Linfocitos T/inmunología , Animales , Antígenos CD19/inmunología , Diferenciación Celular/inmunología , Proliferación Celular/fisiología , Activación de Linfocitos/inmunología , Ratones , Ratones Endogámicos C57BL , Receptores de Antígenos de Linfocitos B/inmunología , Transducción de Señal/inmunología
15.
Phys Chem Chem Phys ; 22(42): 24226-24235, 2020 Nov 14.
Artículo en Inglés | MEDLINE | ID: mdl-33084667

RESUMEN

We present a quantitative study comparing the binding of 4-methoxypyridine, MeOPy, ligand to Co(ii)octaethylporphyrin, CoOEP, at the phenyloctane/HOPG interface and in toluene solution. Scanning tunneling microscopy (STM) was used to study the ligand binding to the porphyrin receptors adsorbed on graphite. Electronic spectroscopy was employed for examining this process in fluid solution. The on surface coordination reaction was completely reversible and followed a simple Langmuir adsorption isotherm. Ligand affinities (or ΔG) for the binding processes in the two different chemical environments were determined from the respective equilibrium constants. The free energy value of -13.0 ± 0.3 kJ mol-1 for the ligation reaction of MeOPy to CoOEP at the solution/HOPG interface is less negative than the ΔG for cobalt porphyrin complexed to the ligand in solution, -16.8 ± 0.2 kJ mol-1. This result indicates that the MeOPy-CoOEP complex is more stable in solution than on the surface. Additional thermodynamic values for the formation of the surface ligated species (ΔHc = -50 kJ mol-1 and ΔSc = -120 J mol-1) were extracted from temperature dependent STM measurements. Density functional computational methods were also employed to explore the energetics of both the solution and surface reactions. At high concentrations of MeOPy the monolayer was observed to be stripped from the surface. Computational results indicate that this is not because of a reduction in adsorption energy of the MeOPy-CoOEP complex. Nearest neighbor analysis of the MeOPy-CoOEP in the STM images revealed positive cooperative ligand binding behavior. Our studies bring new insights to the general principles of affinity and cooperativity in the ligand-receptor interactions at the solution/solid interface. Future applications of STM will pave the way for new strategies designing highly functional multisite receptor systems for sensing, catalysis, and pharmacological applications.

16.
J Am Pharm Assoc (2003) ; 60(6): e246-e251, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32861616

RESUMEN

OBJECTIVES: This study aimed to determine the impact of a pharmacist-led antimicrobial stewardship program (ASP) intervention on outpatient antibiotic prescribing for upper respiratory tract infections (URIs) and urinary tract infections (UTIs) in a primary care office. The primary outcome of this study was to characterize antibiotic prescribing over time. Secondary outcomes included describing ambulatory care pharmacist (ACP) workload and types of feedback given. METHODS: A retrospective pilot study was conducted within a primary care office. The office included a 0.6 full-time equivalent ACP and is part of a health system supported by a pharmacist and a physician co-led ASP. Education and guidelines were provided by the ACP and ASP leads before the intervention period August 2017-February 2018. The ACP provided bi-weekly audit of all URI and UTI prescriptions and written feedback to prescribers. RESULTS: During the 7-month intervention period, 1107 prescriptions were audited by the ACP, 825 URI and 282 UTI. The most common reasons for feedback included inappropriate agent (26.3%) or prolonged duration of therapy (24.3%). Guideline-concordant agent prescribed for a UTI increased from 20% at baseline to a median of 69.2%, whereas duration increased from 55% to 70.4%. Guideline-concordant agent prescribed for a URI increased from 43.3% to 86.8%, whereas the median duration of therapy decreased from 10 to 7 days. CONCLUSION: An ACP-led ASP intervention within a primary care office incorporating audit and feedback improved antibiotic prescribing for URIs and UTIs, including prescribing antibiotics when indicated, guideline-concordant antibiotic selection, and duration of therapy. Pharmacists practicing in ambulatory care settings may serve a vital role in leading successful outpatient ASP interventions.


Asunto(s)
Programas de Optimización del Uso de los Antimicrobianos , Farmacéuticos , Atención Ambulatoria , Antibacterianos/uso terapéutico , Retroalimentación , Humanos , Prescripción Inadecuada , Pacientes Ambulatorios , Proyectos Piloto , Atención Primaria de Salud , Estudios Retrospectivos
17.
Langmuir ; 35(15): 5271-5280, 2019 Apr 16.
Artículo en Inglés | MEDLINE | ID: mdl-30945877

RESUMEN

This study explores directed noncovalent bonding in the self-assembly of nonplanar aromatic carboxylic acids on gold and graphite surfaces. It is the first step in developing a new design strategy to create two-dimensional surface metal-organic frameworks (SURFMOFs). The acid molecules used are tetraphenylethene-based and are typically employed in the synthesis of three-dimensional (3D) MOF crystalline solids. They include tetraphenylethene tetracarboxylic acid, tetraphenylethene bisphenyl carboxylic acid, and tetraphenylethene tetrakis-phenyl carboxylic acid. The two-dimensional structures formed from these molecules on highly ordered pyrolytic graphite (HOPG) and Au(111) are studied by scanning tunneling microscopy in a solution environment. The process of monolayer formation and final surface linker structures are found to be strongly dependent on the combination of the molecule and substrate used and are discussed in terms of intermolecular and molecule-substrate interactions, bonding geometry, and symmetry of the acid molecules. In the case of linker self-assembly on HOPG, the molecule-substrate interactions play a significant role in the resulting surface structure. When the acid molecules are adsorbed on Au(111), the intermolecular interactions tend to dominate over the weaker molecule-substrate bonding. Additionally, the interplay of π-π interactions and hydrogen bonding that directs the surface self-assembly on different supports can be modified by varying the linker concentration. This is particularly applicable for the case of the acid molecules adsorbing on the Au(111) substrate. Precise control over predesigned surface structures and orientation of the nonplanar aromatic carboxylic linkers open up an exciting prospect for manipulating the direction of SURFMOF growth in two dimensions and potentially in 3D.

18.
BMC Neurol ; 19(1): 258, 2019 Oct 28.
Artículo en Inglés | MEDLINE | ID: mdl-31660897

RESUMEN

BACKGROUND: Multiple sclerosis (MS) is prevalent among working age individuals (20-60 years), leading to high burden on work productivity. Few data are available about the absenteeism and presenteeism in employed individuals with MS in comparison to non-MS personnel. This study aimed to quantify the burden of illness of employed US adults with relapsing-remitting multiple sclerosis (RRMS) and examine burden by levels of work impairment. METHODS: A retrospective cross-sectional analysis was conducted using patient-reported responses from the US National Health and Wellness Survey (NHWS). Data from NHWS 2015-2016 were analyzed from 196 employed RRMS respondents who were matched 1:4 to employed respondents without MS based on demographic and general health characteristics. Demographic and general health characteristics for employed RRMS individuals were analyzed by levels of work impairment (none, 1-30%; 31-68%; 69-100%). Work productivity (absenteeism, presenteeism, and work impairment), decrements in health-related quality of life (HRQoL) (short form-36, EQ-5D), and healthcare resource utilization (HCRU) were compared to determine the burden of RRMS. RESULTS: After propensity score matching, the levels of absenteeism and presenteeism were 2 and 1.8 times higher in the employed RRMS population than the employed non-MS population, respectively (P < 0.001 for both). HRQoL was significantly lower in employed respondents with RRMS than those without MS (P < 0.001 for all). Employed respondents with RRMS had significantly more HCRU over 6 months compared to those without MS (P < 0.001). Furthermore, among employed RRMS respondents, greater levels of impairment were associated with increasing disease severity, greater healthcare resource use, fatigue, and cognitive impairment and inversely associated with mental and physical HRQoL (P < 0.0001 for all). CONCLUSIONS: Among employed individuals, respondents with RRMS had lower, work productivity, HRQoL, and higher HCRU as compared with those without MS. Given the large impact RRMS has on work impairment, a need exists to manage individuals on therapies that improve HRQoL, reduce symptoms, and improve their ability to perform in the workforce.


Asunto(s)
Absentismo , Costo de Enfermedad , Esclerosis Múltiple Recurrente-Remitente , Aceptación de la Atención de Salud/estadística & datos numéricos , Adulto , Estudios Transversales , Empleo/estadística & datos numéricos , Femenino , Encuestas Epidemiológicas , Humanos , Masculino , Persona de Mediana Edad , Esclerosis Múltiple Recurrente-Remitente/complicaciones , Calidad de Vida/psicología , Estudios Retrospectivos , Estados Unidos
19.
Proc Natl Acad Sci U S A ; 113(41): 11501-11506, 2016 10 11.
Artículo en Inglés | MEDLINE | ID: mdl-27663736

RESUMEN

A variable region fusion strategy was used to generate an immunosuppressive antibody based on a novel "stalk-knob" structural motif in the ultralong complementary-determining region (CDR) of a bovine antibody. The potent Kv1.3 channel inhibitory peptides Moka1-toxin and Vm24-toxin were grafted into different CDRs of the humanized antibodies BVK and Synagis (Syn) using both ß-sheet and coiled-coil linkers. Structure-activity relationship efforts led to generation of the fusion protein Syn-Vm24-CDR3L, which demonstrated excellent selectivity and potency against effector human memory T cells (subnanomolar to picomolar EC50 values). This fusion antibody also had significantly improved plasma half-life and serum stability in rodents compared with the parent Vm24 peptide. Finally, this fusion protein showed potent in vivo efficacy in the delayed type hypersensitivity in rats. These results illustrate the utility of antibody CDR fusions as a general and effective strategy to generate long-acting functional antibodies, and may lead to a selective immunosuppressive antibody for the treatment of autoimmune diseases.


Asunto(s)
Anticuerpos Bloqueadores/farmacología , Diseño de Fármacos , Inmunosupresores/farmacología , Canal de Potasio Kv1.3/antagonistas & inhibidores , Secuencia de Aminoácidos , Animales , Células CHO , Bovinos , Regiones Determinantes de Complementariedad/química , Cricetinae , Cricetulus , Células HEK293 , Humanos , Activación de Linfocitos/efectos de los fármacos , Ratas , Proteínas Recombinantes de Fusión/química , Proteínas Recombinantes de Fusión/farmacología
20.
Pain Manag Nurs ; 20(1): 25-31, 2019 02.
Artículo en Inglés | MEDLINE | ID: mdl-29501361

RESUMEN

BACKGROUND: Pain is one of the most feared of all symptoms for the cancer patient. Some studies estimate that up to 90% of all cancer patients experience pain. Advances in pharmaceuticals and expert provider knowledge have improved pain management overall for the patient with cancer; however, complementary therapies can synergize medications to provide optimal pain relief while decreasing the side effect profile. Despite this, nurses may have limited access to such resources. Many therapies can be administered directly by the bedside/chairside nurse with minimal training and the nurse can then teach the patient and family how to use the selected complementary therapy after leaving the hospital or clinic. OBJECTIVES: The oncology nurse will be able to identify several easy-to-implement complementary therapies that can supplement pharmacologic pain management for cancer patients. METHODS: As a quality project, comfort kits, containing such items as handheld massagers, guided imagery audiotapes, and aromatherapy essential oils, were distributed for use with patients through unit-based pain resource nurses. ANALYSIS: More than 500 comfort kit items were tracked by the pain clinical nurse specialist during the comfort kit trial, both by medical record review and by follow-up phone calls to patients. During the comfort kit trial, average pain intensity decreased by 2.25 points on a 0-10 scale in the 24-hour period after use of the item from the comfort kit. Patients also had an overall decrease in the use of pharmacologic pain interventions and an increase in ambulation in the 24-hour period after implementation. CONCLUSIONS: Comfort kits allow nurses easy access to inexpensive tools to supplement pharmaceutical pain management. Optimizing nonpharmacologic pain management can increase patient and nurse satisfaction, improve overall pain management, and decrease untoward side effects.


Asunto(s)
Neoplasias/terapia , Manejo del Dolor/normas , Comodidad del Paciente/métodos , Adulto , Terapias Complementarias/enfermería , Humanos , Neoplasias/complicaciones , Enfermería Oncológica/métodos , Manejo del Dolor/métodos , Comodidad del Paciente/normas , Encuestas y Cuestionarios
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