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1.
EMBO Rep ; 24(11): e57264, 2023 11 06.
Artículo en Inglés | MEDLINE | ID: mdl-37702953

RESUMEN

Cytoplasmic microtubules are tubular polymers that can harbor small proteins or filaments inside their lumen. The identities of these objects and mechanisms for their accumulation have not been conclusively established. Here, we used cryogenic electron tomography of Drosophila S2 cell protrusions and found filaments inside the microtubule lumen, which resemble those reported recently in human HAP1 cells. The frequency of these filaments increased upon inhibition of the sarco/endoplasmic reticulum Ca2+ ATPase with the small molecule drug thapsigargin. Subtomogram averaging showed that the luminal filaments adopt a helical structure reminiscent of cofilin-bound actin (cofilactin). Consistent with this, we observed cofilin dephosphorylation, an activating modification, in cells under the same conditions that increased luminal filament occurrence. Furthermore, RNA interference knock-down of cofilin reduced the frequency of luminal filaments with cofilactin morphology. These results suggest that cofilin activation stimulates its accumulation on actin filaments inside the microtubule lumen.


Asunto(s)
Citoesqueleto de Actina , Citoesqueleto , Humanos , Citoesqueleto/metabolismo , Citoesqueleto de Actina/metabolismo , Actinas/metabolismo , Factores Despolimerizantes de la Actina/metabolismo , Microtúbulos/metabolismo
2.
J Exp Biol ; 227(8)2024 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-38584490

RESUMEN

The mechanical forces experienced during movement and the time constants of muscle activation are important determinants of the durations of behaviours, which may both be affected by size-dependent scaling. The mechanics of slow movements in small animals are dominated by elastic forces and are thus quasistatic (i.e. always near mechanical equilibrium). Muscular forces producing movement and elastic forces resisting movement should scale identically (proportional to mass2/3), leaving the scaling of the time constant of muscle activation to play a critical role in determining behavioural duration. We tested this hypothesis by measuring the duration of feeding behaviours in the marine mollusc Aplysia californica whose body sizes spanned three orders of magnitude. The duration of muscle activation was determined by measuring the time it took for muscles to produce maximum force as A. californica attempted to feed on tethered inedible seaweed, which provided an in vivo approximation of an isometric contraction. The timing of muscle activation scaled with mass0.3. The total duration of biting behaviours scaled identically, with mass0.3, indicating a lack of additional mechanical effects. The duration of swallowing behaviour, however, exhibited a shallower scaling of mass0.17. We suggest that this was due to the allometric growth of the anterior retractor muscle during development, as measured by micro-computed tomography (micro-CT) scans of buccal masses. Consequently, larger A. californica did not need to activate their muscles as fully to produce equivalent forces. These results indicate that muscle activation may be an important determinant of the scaling of behavioural durations in quasistatic systems.


Asunto(s)
Aplysia , Músculos , Animales , Aplysia/fisiología , Microtomografía por Rayos X , Músculos/fisiología , Conducta Alimentaria/fisiología , Deglución/fisiología
3.
Mol Cell Proteomics ; 21(11): 100420, 2022 11.
Artículo en Inglés | MEDLINE | ID: mdl-36182099

RESUMEN

Biomolecular integrity can be compromised when blood plasma/serum (P/S) specimens are improperly handled. Compromised analytes can subsequently produce erroneous results-without any indication of having done so. We recently introduced an LC/MS-based marker of P/S exposure to thawed conditions called ΔS-Cys-Albumin which, aided by an established rate law, quantitatively tracks exposure of P/S to temperatures greater than their freezing point of -30 °C. The purposes of this study were to (1) evaluate ΔS-Cys-Albumin baseline values in gastrointestinal cancer patients and cancer-free control donors, (2) empirically assess the kinetic profiles of ΔS-Cys-Albumin at 23 °C, 4 °C, and -20 °C, and (3) empirically link ΔS-Cys-Albumin to the stability of clinically relevant proteins. ΔS-Cys-Albumin was measured at ≥ 9 different time points per exposure temperature in serum and K2EDTA plasma samples from 24 separate donors in aliquots kept separately at 23 °C, 4 °C, and -20 °C. Twenty-one clinically relevant plasma proteins were measured at four time points per temperature via a multiplexed immunoassay on the Luminex platform. Protein stability was assessed by mixed effects models. Coordinated shifts in stability between ΔS-Cys-Albumin and the unstable proteins were documented by repeated measures and Pearson correlations. Plasma ΔS-Cys-Albumin dropped from approximately 20% to under 5% within 96 h at 23 °C, 28 days at 4 °C, and 65 days at -20 °C. On average, 22% of the 21 proteins significantly changed in apparent concentration at each exposure temperature (p < 0.0008 with >10% shift). A linear inverse relationship was found between the percentage of proteins destabilized and ΔS-Cys-Albumin (r = -0.61; p < 0.0001)-regardless of the specific time/temperature of exposure. ΔS-Cys-Albumin tracks cumulative thawed-state exposure. These results now enable ΔS-Cys-Albumin to approximate the percentage of clinically relevant proteins that have been compromised by incidental plasma exposure to thawed-state conditions.


Asunto(s)
Proteínas Sanguíneas , Plasma , Humanos , Espectrometría de Masas , Cromatografía Liquida , Plasma/metabolismo , Albúmina Sérica , Biomarcadores , Temperatura
4.
BMC Pediatr ; 23(1): 115, 2023 03 08.
Artículo en Inglés | MEDLINE | ID: mdl-36890502

RESUMEN

BACKGROUND: To examine the differential relationships between seven social risk factors (individually and cumulatively) with the prevalence and severity of asthma, attention deficit hyperactivity disorder (ADHD), autism spectrum disorder (ASD), and overweight/obesity in children. METHODS: Using the 2017-2018 National Survey of Children's Health, we examined associations between social risk factors (caregiver education, caregiver underemployment, discrimination, food insecurity, insurance coverage, neighborhood support, and neighborhood safety) and the prevalence and severity of asthma, ADHD, ASD, and overweight/obesity. We used multivariable logistic regression to assess the relationship between individual and cumulative risk factors with each pediatric chronic condition, controlling for child sex and age. RESULTS: Although each social risk factor was significantly associated with increased prevalence and/or severity of at least one of the pediatric chronic conditions we investigated, food insecurity was significantly associated with higher disease prevalence and severity for all four conditions. Caregiver underemployment, low social support, and discrimination were significantly associated with higher disease prevalence across all conditions. For each additional social risk factor a child was exposed to, their odds of having each condition increased: overweight/obesity (aOR: 1.2, 95% CI: [1.2, 1.3]), asthma (aOR: 1.3, 95% CI: [1.2, 1.3], ADHD (aOR: 1.2, 95% CI: [1.2, 1.3]), and ASD (aOR: 1.4, 95% CI: [1.3, 1.5]). CONCLUSIONS: This study elucidates differential relationships between several social risk factors and the prevalence and severity of common pediatric chronic conditions. While more research is needed, our results suggest that social risks, particularly food insecurity, are potential factors in the development of pediatric chronic conditions.


Asunto(s)
Asma , Trastorno por Déficit de Atención con Hiperactividad , Trastorno del Espectro Autista , Obesidad Infantil , Niño , Humanos , Trastorno del Espectro Autista/etiología , Trastorno del Espectro Autista/complicaciones , Estudios Transversales , Sobrepeso/complicaciones , Obesidad Infantil/epidemiología , Obesidad Infantil/complicaciones , Prevalencia , Trastorno por Déficit de Atención con Hiperactividad/etiología , Trastorno por Déficit de Atención con Hiperactividad/complicaciones , Asma/epidemiología , Asma/complicaciones
5.
J Allergy Clin Immunol ; 150(6): 1476-1485.e4, 2022 12.
Artículo en Inglés | MEDLINE | ID: mdl-35839842

RESUMEN

BACKGROUND: Circulating IgE and subsequent severe allergic reactions to peanut are sustained and propagated by recall of peanut allergen-specific memory B cells. OBJECTIVES: This study aimed to determine whether targeting mouse and human CD22 on peanut-specific memory B cells induces tolerance to peanut allergens. METHODS: Siglec-engaging tolerance-inducing antigenic liposomes (STALs) codisplaying peanut allergens (Ara h 1, Ara h 2, or Ara h 3) and high-affinity CD22 ligand (CD22L-STALs) were employed in various mouse models (BALB/cJ, C57BL/6, human CD22 transgenic, and NSG) of peanut allergy. To investigate memory B cells, a conferred memory model was used in which splenocytes from peanut-sensitized mice were transferred into naive animals. Reconstituted mice received either CD22L-STALs or an immunogenic liposome control, followed by a peanut allergen boost and later a challenge with individual peanut allergens. To assess the effects of CD22L-STALs on human B cells, PBMCs were injected into NSG mice, followed by administration of human CD22L-STALs (hCD22L-STALs) and later a whole peanut extract boost. Blood was collected to quantify WPE- and Ara h 1-, 2-, and 3-specific immunoglobulins. RESULTS: Mouse CD22L-STALs (mCD22L-STALs) significantly suppressed systemic memory to Ara h 1, Ara h 2, and Ara h 3 in BALB/cJ and C57BL/6 mice, as demonstrated by reduced allergen-specific IgE, IgG1, and anaphylaxis on challenge. Importantly, 2 doses of mCD22L-STALs led to prolonged tolerance for at least 3 months. hCD22L-STALs displayed similar suppression in mice expressing human CD22 on B cells. Finally, human B cells were tolerized in vivo in NSG mice by hCD22L-STALs. CONCLUSIONS: Antigen-specific exploitation of CD22 on memory B cells can induce systemic immune tolerance.


Asunto(s)
Alérgenos , Arachis , Humanos , Ratones , Animales , Ratones Endogámicos C57BL , Células B de Memoria , Tolerancia Inmunológica , Lectina 2 Similar a Ig de Unión al Ácido Siálico
6.
J Nematol ; 55(1): 20230003, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-36880011

RESUMEN

Specimens of a tylenchid nematode were recovered in 2019 from soil samples collected from a corn field, located in Pickens County, South Carolina, USA. A moderate number of Tylenchus sp. adults (females and males) were recovered. Extracted nematodes were examined morphologically and molecularly for species identification, which indicated that the specimens of the tylenchid adults were a new species, described herein as Tylenchus zeae n. sp. Morphological examination and the morphometric details of the specimens were very close to the original descriptions of Tylenchus sherianus and T. rex. However, females of the new species can be differentiated from these species by body shape and length, shape of excretory duct, distance between anterior end and esophageal intestinal valve, and a few other characteristics given in the diagnosis. Males of the new species can be differentiated from the two closely related species by tail, spicules, and gubernaculum length. Cryo-scanning electron microscopy confirmed head bearing five or six annules; four to six cephalic sensilla represented by small pits at the rounded corners of the labial plate; a small, round oral plate; and a large, pit-like amphidial opening confined to the labial plate and extending three to four annules beyond it. Phylogenetic analysis of 18S rRNA gene sequences placed Tylenchus zeae n. sp. in a clade with Tylenchus arcuatus and several Filenchus spp., and the mitochondrial cytochrome oxidase c subunit 1 (COI) gene region separated the new species from T. arcuatus and other tylenchid species. In the 28S tree, T. zeae n. sp. showed a high level of sequence divergence and was positioned outside of the main Tylenchus-Filenchus clade.

7.
Circulation ; 144(11): 870-889, 2021 09 14.
Artículo en Inglés | MEDLINE | ID: mdl-34229449

RESUMEN

BACKGROUND: Current paradigms suggest that nitric oxide (NO) produced by endothelial cells (ECs) through endothelial nitric oxide synthase (eNOS) in the vessel wall is the primary regulator of blood flow and blood pressure. However, red blood cells (RBCs) also carry a catalytically active eNOS, but its role is controversial and remains undefined. This study aimed to elucidate the functional significance of RBC eNOS compared with EC eNOS for vascular hemodynamics and nitric oxide metabolism. METHODS: We generated tissue-specific loss- and gain-of-function models for eNOS by using cell-specific Cre-induced gene inactivation or reactivation. We created 2 founder lines carrying a floxed eNOS (eNOSflox/flox) for Cre-inducible knockout (KO), and gene construct with an inactivated floxed/inverted exon (eNOSinv/inv) for a Cre-inducible knock-in (KI), which respectively allow targeted deletion or reactivation of eNOS in erythroid cells (RBC eNOS KO or RBC eNOS KI mice) or in ECs (EC eNOS KO or EC eNOS KI mice). Vascular function, hemodynamics, and nitric oxide metabolism were compared ex vivo and in vivo. RESULTS: The EC eNOS KOs exhibited significantly impaired aortic dilatory responses to acetylcholine, loss of flow-mediated dilation, and increased systolic and diastolic blood pressure. RBC eNOS KO mice showed no alterations in acetylcholine-mediated dilation or flow-mediated dilation but were hypertensive. Treatment with the nitric oxide synthase inhibitor Nγ-nitro-l-arginine methyl ester further increased blood pressure in RBC eNOS KOs, demonstrating that eNOS in both ECs and RBCs contributes to blood pressure regulation. Although both EC eNOS KOs and RBC eNOS KOs had lower plasma nitrite and nitrate concentrations, the levels of bound NO in RBCs were lower in RBC eNOS KOs than in EC eNOS KOs. Reactivation of eNOS in ECs or RBCs rescues the hypertensive phenotype of the eNOSinv/inv mice, whereas the levels of bound NO were restored only in RBC eNOS KI mice. CONCLUSIONS: These data reveal that eNOS in ECs and RBCs contribute independently to blood pressure homeostasis.


Asunto(s)
Presión Sanguínea/fisiología , Células Endoteliales/metabolismo , Eritrocitos/metabolismo , Óxido Nítrico Sintasa de Tipo III/metabolismo , Óxido Nítrico/metabolismo , Acetilcolina/farmacología , Animales , Enfermedades de la Aorta/tratamiento farmacológico , Arginina/análogos & derivados , Arginina/farmacología , Presión Sanguínea/efectos de los fármacos , Recuento de Eritrocitos/métodos , Hipertensión/metabolismo , Hipertensión/fisiopatología , Ratones
8.
Artículo en Inglés | MEDLINE | ID: mdl-36208310

RESUMEN

Crickets receive auditory information from their environment via ears located on the front legs. Ascending interneurons forward auditory activity to the brain, which houses a pattern recognition network for phonotaxis to conspecific calling songs and which controls negative phonotaxis to high-frequency sound pulses. Descending brain neurons, however, which are clearly involved in controlling these behaviors, have not yet been identified. We describe a descending auditory-responsive brain neuron with an arborization pattern that coincides with the ring-like auditory neuropil in the brain formed by the axonal arborizations of ascending and local interneurons, indicating its close link to auditory processing. Spiking activity of this interneuron occurs with a short latency to calling song patterns and the neuron copies the sound pulse pattern. The neuron preferentially responds to short sound pulses, but its activity appears to be independent of the calling song pattern recognition process. It also receives a weaker synaptic input in response to high-frequency pulses, which may contribute to its short latency spiking responses. This interneuron could be a crucial part in the auditory-to-motor transformation of the nervous system and contribute to the motor control of cricket auditory behavior.


Asunto(s)
Vías Auditivas , Gryllidae , Animales , Vías Auditivas/fisiología , Gryllidae/fisiología , Potenciales de Acción/fisiología , Interneuronas/fisiología , Encéfalo/fisiología , Estimulación Acústica
9.
BMC Pediatr ; 22(1): 155, 2022 03 24.
Artículo en Inglés | MEDLINE | ID: mdl-35331170

RESUMEN

BACKGROUND: The Supplemental Nutrition Assistance Program (SNAP) has well-established positive impacts on child health outcomes, including increased birth weight and decreased likelihood of underweight status. Studies in adult populations suggest that SNAP is associated with lower health care costs, although less is known in children. METHODS: Retrospective analysis of U.S. children (age <18 years) living in low-income households (< 200% of the federal poverty level) in the 2013-2017 Medical Expenditure Panel Survey. We used multivariable regression, adjusting for sociodemographic and clinical covariates, to model the effect of continuous SNAP enrollment on health expenditures as compared to non-enrollees at 12 and 24 months. RESULTS: The sample included 5,626 children, of whom 49.2% consistently received SNAP for the entire two-year survey period. Compared with SNAP non-recipients, SNAP-recipient households more often had incomes below 100% FPL (78.3% vs 37.9%), and children in SNAP-recipient households were more often publicly insured (94.9% vs 64.5%). Unadjusted expenditures were lower for children in SNAP-recipient households at 12 ($1222 vs $1603) and 24 months ($2447 vs $3009). However, when adjusting for sociodemographic and clinical differences, no statistically significant differences in health care expenditures, including emergency department, inpatient, outpatient, and prescription costs, were identified. CONCLUSION: SNAP participant children experience heightened social hardships across multiple domains. There were no differences in short term health care costs based on SNAP enrollment when accounting for differences in sociodemographic and clinical factors. Despite demonstrated child health benefits, we found that sustained enrollment in SNAP over a two-year period did not generate significant short- term health care cost reductions. Our findings suggest that although SNAP is intended to act as a benefit towards the health and well-being of its recipients, unlike among adults, it may not reduce health care costs among children.


Asunto(s)
Asistencia Alimentaria , Gastos en Salud , Adolescente , Adulto , Niño , Composición Familiar , Humanos , Pobreza , Estudios Retrospectivos
10.
Haematologica ; 106(11): 2971-2985, 2021 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-33979990

RESUMEN

Band 3 (anion exchanger 1; AE1) is the most abundant membrane protein in red blood cells, which in turn are the most abundant cells in the human body. A compelling model posits that, at high oxygen saturation, the N-terminal cytosolic domain of AE1 binds to and inhibits glycolytic enzymes, thus diverting metabolic fluxes to the pentose phosphate pathway to generate reducing equivalents. Dysfunction of this mechanism occurs during red blood cell aging or storage under blood bank conditions, suggesting a role for AE1 in the regulation of the quality of stored blood and efficacy of transfusion, a life-saving intervention for millions of recipients worldwide. Here we leveraged two murine models carrying genetic ablations of AE1 to provide mechanistic evidence of the role of this protein in the regulation of erythrocyte metabolism and storage quality. Metabolic observations in mice recapitulated those in a human subject lacking expression of AE11-11 (band 3 Neapolis), while common polymorphisms in the region coding for AE11-56 correlate with increased susceptibility to osmotic hemolysis in healthy blood donors. Through thermal proteome profiling and crosslinking proteomics, we provide a map of the red blood cell interactome, with a focus on AE11-56 and validate recombinant AE1 interactions with glyceraldehyde 3-phosphate dehydrogenase. As a proof-of-principle and to provide further mechanistic evidence of the role of AE1 in the regulation of redox homeo stasis of stored red blood cells, we show that incubation with a cell-penetrating AE11-56 peptide can rescue the metabolic defect in glutathione recycling and boost post-transfusion recovery of stored red blood cells from healthy human donors and genetically ablated mice.


Asunto(s)
Proteína 1 de Intercambio de Anión de Eritrocito , Eritrocitos , Animales , Proteína 1 de Intercambio de Anión de Eritrocito/química , Bancos de Sangre , Eritrocitos/metabolismo , Hemólisis , Humanos , Ratones , Oxidación-Reducción , Vía de Pentosa Fosfato
11.
Transfusion ; 61(5): 1586-1599, 2021 05.
Artículo en Inglés | MEDLINE | ID: mdl-33830505

RESUMEN

BACKGROUND: During storage, red blood cells (RBCs) undergo significant biochemical and morphologic changes, referred to collectively as the "storage lesion". It was hypothesized that these defects may arise from disrupted oxygen-based regulation of RBC energy metabolism, with resultant depowering of intrinsic antioxidant systems. STUDY DESIGN AND METHODS: As a function of storage duration, the dynamic range in RBC metabolic response to three models of biochemical oxidant stress (methylene blue, hypoxanthine/xanthine oxidase, and diamide) was assessed, comparing glycolytic flux by NMR and UHPLC-MS methodologies. Blood was processed/stored under standard conditions (AS-1 additive solution) with leukoreduction. Over a 6-week period, RBC metabolic and antioxidant status were assessed at baseline and following exposure to the three biochemical oxidant models. Comparison was made of glycolytic flux (1 H-NMR tracking of [2-13 C]-glucose and metabolomic phenotyping with [1,2,3-13 C3 ] glucose), reducing equivalent (NADPH/NADP+ ) recycling, and thiol-based (GSH/GSSG) antioxidant status. RESULTS: As a function of storage duration, we observed the following: (1) a reduction in baseline hexose monophosphate pathway (HMP) flux, the sole pathway responsible for the regeneration of the essential reducing equivalent NADPH; with (2) diminished stress-based dynamic range in both overall glycolytic as well as proportional HMP flux. In addition, progressive with storage duration, RBCs showed (3) constraint in reducing equivalent (NADPH) recycling capacity, (4) loss of thiol based (GSH) recycling capacity, and (5) dysregulation of metabolon assembly at the cytoplasmic domain of Band 3 membrane protein (cdB3). CONCLUSION: Blood storage disturbs normal RBC metabolic control, depowering antioxidant capacity and enhancing vulnerability to oxidative injury.


Asunto(s)
Conservación de la Sangre , Metabolismo Energético , Eritrocitos/metabolismo , Conservación de la Sangre/métodos , Eritrocitos/citología , Glucosa/metabolismo , Disulfuro de Glutatión/metabolismo , Glucólisis , Humanos , Metabolómica , NADP/metabolismo , Estrés Oxidativo
12.
J Exp Biol ; 224(11)2021 06 01.
Artículo en Inglés | MEDLINE | ID: mdl-34114627

RESUMEN

For crickets, which approach singing males by phonotaxis, the female choosiness hypothesis postulates that young females should be more selective of male calling song patterns than older individuals. However, there is no information about the behavioural preferences of females over their complete adulthood. We analysed phonotaxis in female Gryllus bimaculatus throughout their entire adult lifetime and measured the impact of sound amplitude, carrier frequency and the temporal pattern of test songs on their auditory response. Females of all ages demonstrated their best responses to male calling songs with a pulse period of 34-42 ms, a carrier frequency of 4.5 kHz and a sound pressure level of 75 dB. The response profile to somewhat less optimal song types did vary with age, but not in a manner consistent with a simple loosening of selectiveness in older females. Age, however, had an effect on the overall strength of phonotaxis, as very old females showed an overall diminishing response to all song types. Our data suggest that although there are minor changes in the relative preferences of crickets to individual song elements as they age, the breadth of song patterns to which they will perform phonotaxis remains similar across age groups.


Asunto(s)
Gryllidae , Adulto , Anciano , Animales , Percepción Auditiva , Femenino , Humanos , Masculino , Sonido , Vocalización Animal
13.
J Nematol ; 532021.
Artículo en Inglés | MEDLINE | ID: mdl-34881368

RESUMEN

A high number of second stage juveniles of the root-knot nematode were recovered from soil samples collected from a corn field, located in Pickens County, South Carolina, USA in 2019. Extracted nematodes were examined morphologically and molecularly for species identification which indicated that the specimens of root knot juveniles were Meloidogyne hispanica. The morphological examination and morphometric details from second-stage juveniles were consistent with the original description and redescriptions of this species. The ITS rRNA, D2-D3 expansion segments of 28S rRNA, intergenic COII-16S region, nad5 and COI gene sequences were obtained from the South Carolina population of M. hispanica. Phylogenetic analysis of the intergenic COII-16S region of mtDNA gene sequence alignment using statistical parsimony showed that the South Carolina population clustered with Meloidogyne hispanica from Portugal and Australia. To our best knowledge, this finding represents the first report of Meloidogyne hispanica in the USA and North America.

14.
Dev Biol ; 455(2): 409-419, 2019 11 15.
Artículo en Inglés | MEDLINE | ID: mdl-31325455

RESUMEN

Arrestins control signaling via the G protein coupled receptors (GPCRs), serving as both signal terminators and transducers. Previous studies identified several structural elements in arrestins that contribute to their functions as GPCR regulators. However, the importance of these elements in vivo is unclear, and the developmental roles of arrestins are not well understood. We carried out an in vivo structure-function analysis of Kurtz (Krz), the single ortholog of mammalian ß-arrestins in the Drosophila genome. A combination of Krz mutations affecting the GPCR-phosphosensing and receptor core-binding ("finger loop") functions (Krz-KKVL/A) resulted in a complete loss of Krz activity during development. Endosome recruitment and bioluminescence resonance energy transfer (BRET) assays revealed that the KKVL/A mutations abolished the GPCR-binding ability of Krz. We found that the isolated "finger loop" mutation (Krz-VL/A), while having a negligible effect on GPCR internalization, severely affected Krz function, suggesting that tight receptor interactions are necessary for proper termination of signaling in vivo. Genetic analysis as well as live imaging demonstrated that mutations in Krz led to hyperactivity of the GPCR Mist (also known as Mthl1), which is activated by its ligand Folded gastrulation (Fog) and is responsible for cellular contractility and epithelial morphogenesis. Krz mutations affected two developmental events that are under the control of Fog-Mist signaling: gastrulation and morphogenesis of the wing. Overall, our data reveal the functional importance in vivo of direct ß-arrestin/GPCR binding, which is mediated by the recognition of the phosphorylated receptor tail and receptor core interaction. These Krz-GPCR interactions are critical for setting the correct level of Fog-Mist signaling during epithelial morphogenesis.


Asunto(s)
Arrestinas/fisiología , Proteínas de Drosophila/fisiología , Drosophila/fisiología , Receptores Acoplados a Proteínas G/metabolismo , Secuencias de Aminoácidos , Animales , Arrestinas/química , Regulación hacia Abajo , Drosophila/embriología , Proteínas de Drosophila/química , Proteínas de Drosophila/metabolismo , Femenino , Gastrulación , Masculino , Modelos Moleculares , Conformación Proteica , Transducción de Señal , Relación Estructura-Actividad , Alas de Animales/embriología
15.
BMC Med ; 18(1): 198, 2020 07 27.
Artículo en Inglés | MEDLINE | ID: mdl-32713349

RESUMEN

BACKGROUND: Cardiovascular disease is responsible for 31% of all global deaths. Primary prevention strategies are needed to improve longer-term adherence to statins and healthy lifestyle behaviours to reduce risk in people at risk of cardiovascular disease. METHODS: Pragmatic randomised controlled trial recruited between May 2016 and March 2017 from primary care practices, England. Participants (n = 212) prescribed statins for primary prevention of cardiovascular disease with total cholesterol level ≥ 5 mmol/l were randomised: 105 to the intervention group and 107 to the control group, stratified by age and sex. The 3R intervention involved two facilitated, structured group education sessions focusing on medication adherence to statins, lifestyle behaviours and cardiovascular risk, with 44 weeks of medication reminders and motivational text messages and two supportive, coaching phone calls (at approximately 2 weeks and 6 months). The control group continued with usual clinical care. Both groups received a basic information leaflet. The primary outcome was medication adherence to statins objectively measured by a biochemical urine test. Self-reported adherence and practice prescription data provided additional measures. Secondary outcomes included cholesterol profile, blood pressure, anthropometric data, cardiovascular risk score, and self-reported lifestyle behaviours and psychological measures (health/medication beliefs, quality of life, health status). All outcomes were assessed at 12 months. RESULTS: Baseline adherence to statins was 47% (control) and 62% (intervention). No significant difference between the groups found for medication adherence to statins using either the urine test (OR 1.02, 95% CI 0.34 to 3.06, P = 0.968) or other measures. This may have been due to the higher than expected adherence levels at baseline. The adjusted mean difference between the groups (in favour of the intervention group) for diastolic blood pressure (- 4.28 mmHg (95% CI - 0.98 to - 1.58, P = 0.002)) and waist circumference (- 2.55 cm (95% CI - 4.55 to - 0.55, P = 0.012)). The intervention group also showed greater perceived control of treatment and more coherent understanding of the condition. CONCLUSIONS: The 3R programme successfully led to longer-term improvements in important clinical lifestyle indicators but no improvement in medication adherence, raising questions about the suitability of such a broad, multiple risk factor approach for improving medication adherence for primary prevention of CVD. TRIAL REGISTRATION: International Standard Randomized Controlled Trial Number (ISRCTN16863160), March 11, 2006.


Asunto(s)
Enfermedades Cardiovasculares/prevención & control , Prevención Primaria/métodos , Calidad de Vida/psicología , Adulto , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Factores de Riesgo , Adulto Joven
16.
J Am Soc Nephrol ; 30(7): 1261-1270, 2019 07.
Artículo en Inglés | MEDLINE | ID: mdl-31097609

RESUMEN

BACKGROUND: Most patients with CKD are managed in the community. Whether nurse-led CKD management programs improve outcomes in patients with CKD in primary care is unclear. METHODS: To assess the effect of such a program on the rate of renal function decline in patients with CKD (stages 3-5) in primary care in the United Kingdom, we conducted a cluster randomized trial, the Primary-Secondary Care Partnership to Improve Outcomes in Chronic Kidney Disease study. A software program designed for the study created a data file of patients with CKD in participating practices. In 23 intervention practices (11,651 patients), a CKD nurse practitioner worked with nominated practice leads to interpret the data file and implement guideline-based patient-level CKD management interventions. The 23 control practices (11,706 patients) received a data file but otherwise, continued usual CKD care. The primary outcome was defined at the cluster (practice) level as the change from baseline of the mean eGFR of the patients with CKD at 6-month intervals up to 42 months. Secondary outcomes included numbers of patients coded for CKD, mean BP, numbers of patients achieving National Institute for Health and Care Excellence BP targets for CKD, and proteinuria measurement. RESULTS: After 42 months, eGFR did not differ significantly between control and intervention groups. CKD- and proteinuria-related coding improved significantly along with the number of patients achieving BP targets in the intervention group versus usual care. CONCLUSIONS: CKD management programs in primary care may not slow progression of CKD, but they may significantly improve processes of care and potentially decrease the cardiovascular disease burden in CKD and related costs.


Asunto(s)
Atención Primaria de Salud , Insuficiencia Renal Crónica/terapia , Atención Secundaria de Salud , Análisis por Conglomerados , Tasa de Filtración Glomerular , Costos de la Atención en Salud , Humanos , Enfermeras Practicantes , Insuficiencia Renal Crónica/fisiopatología
17.
J Nematol ; 52: 1-4, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32180381

RESUMEN

In the spring of 2019, a cyst nematode was discovered from soil samples collected from an alfalfa field in Millard County, Utah. The soil samples were submitted to one of us (SH), who extracted the nematode cysts and sent them to the USDA-ARS, Mycology and Nematology Genetic Diversity and Biology Laboratory (MNGDBL), Beltsville, MD for morphological and molecular identification. Cysts and living nematode juveniles (J2) recovered from the cysts were examined morphologically and molecularly for species identification which indicated that the specimens were Heterodera medicaginis. This represents the first record of H. medicaginis in Utah and the second report of this nematode in North America.In the spring of 2019, a cyst nematode was discovered from soil samples collected from an alfalfa field in Millard County, Utah. The soil samples were submitted to one of us (SH), who extracted the nematode cysts and sent them to the USDA-ARS, Mycology and Nematology Genetic Diversity and Biology Laboratory (MNGDBL), Beltsville, MD for morphological and molecular identification. Cysts and living nematode juveniles (J2) recovered from the cysts were examined morphologically and molecularly for species identification which indicated that the specimens were Heterodera medicaginis. This represents the first record of H. medicaginis in Utah and the second report of this nematode in North America.

18.
Transfusion ; 59(S2): 1568-1577, 2019 04.
Artículo en Inglés | MEDLINE | ID: mdl-30980740

RESUMEN

BACKGROUND: We set out to define the impact of collection, processing, and storage on plasma product microparticle (MP) abundance, potential for nitric oxide (NO) scavenging, and vasoactivity. STUDY DESIGN AND METHODS: Three currently US licensed products were tested: liquid plasma (LP), fresh frozen plasma (FFP), and solvent detergent plasma (SDP), along with a product under development, spray-dried solvent detergent plasma (SD-SDP) with/without beads. Vasoactivity was assessed in vitro using rabbit aortic vascular rings; MP abundance was determined by flow cytometry; and NO scavenging capacity/rate was determined using a biochemical NO consumption assay. All samples were analyzed unprocessed and following centrifugation at two speeds (2,500× g to remove platelets, and 25,000× g to remove microparticles). RESULTS: Significant differences in vasoactivity were observed, with SD-SDP minus beads demonstrating the greatest constriction and FFP the lowest constriction response. All products exhibited the same total NO scavenging capacity; however, significant differences were observed in the maximal rate of scavenging, with SD-SDP minus beads and FFP reacting fastest and SDP the slowest. Across all products, platelet and microparticle depletion had no effect on vasoactivity or NO scavenging (total or rate). Microparticles (RBC derived) were found only in FFP and LP, with relative abundance (LP > FFP). Additionally, storage had no effect on total or RBC-derived MP abundance, NO scavenging, or vasoactivity. CONCLUSION: Although vasoactivity differed between plasma products, we did not find similar differences in either total or RBC-derived MP abundance or NO scavenging capacity/rate.


Asunto(s)
Aorta/metabolismo , Conservación de la Sangre , Micropartículas Derivadas de Células/química , Eritrocitos/química , Depuradores de Radicales Libres , Plasma/química , Vasoconstrictores , Animales , Aorta/fisiopatología , Depuradores de Radicales Libres/química , Depuradores de Radicales Libres/farmacología , Humanos , Óxido Nítrico/metabolismo , Conejos , Vasoconstrictores/química , Vasoconstrictores/farmacología
19.
EMBO J ; 33(2): 96-8, 2014 Jan 13.
Artículo en Inglés | MEDLINE | ID: mdl-24421323

RESUMEN

Proteins residing at the plus and minus ends of microtubules have been thought not to communicate with each other, but recent findings on bona fide nucleation factors also regulating microtubule dynamics have challenged this notion. New work by Bouissou et al (2014) in The EMBO Journal now reveals that interplay between the nucleation factor γ­TuRC and the plus­end tracking protein EB1 controls mitotic spindle positioning by affecting the stability and dynamics of astral microtubules.


Asunto(s)
Proteínas Asociadas a Microtúbulos/fisiología , Microtúbulos/metabolismo , Huso Acromático/fisiología , Tubulina (Proteína)/fisiología , Animales , Humanos
20.
J Cell Sci ; 129(1): 121-34, 2016 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-26585311

RESUMEN

Coordination between different cytoskeletal systems is crucial for many cell biological functions, including cell migration and mitosis, and also plays an important role during tissue morphogenesis. Proteins of the class of cytoskeletal crosslinkers, or cytolinkers, have the ability to interact with more than one cytoskeletal system at a time and are prime candidates to mediate any coordination. One such class comprises the Gas2-like proteins, combining a conserved calponin-homology-type actin-binding domain and a Gas2 domain predicted to bind microtubules (MTs). This domain combination is also found in spectraplakins, huge cytolinkers that play important roles in many tissues in both invertebrates and vertebrates. Here, we dissect the ability of the single Drosophila Gas2-like protein Pigs to interact with both actin and MT cytoskeletons, both in vitro and in vivo, and illustrate complex regulatory interactions that determine the localisation of Pigs to and its effects on the cytoskeleton.


Asunto(s)
Polaridad Celular , Proteínas de Drosophila/metabolismo , Drosophila melanogaster/metabolismo , Péptidos y Proteínas de Señalización Intracelular/metabolismo , Microtúbulos/metabolismo , Citoesqueleto de Actina/metabolismo , Actinas/metabolismo , Secuencias de Aminoácidos , Animales , Células Cultivadas , Proteínas de Drosophila/química , Proteínas de Drosophila/genética , Péptidos y Proteínas de Señalización Intracelular/química , Péptidos y Proteínas de Señalización Intracelular/genética , Mutación/genética , Unión Proteica , Estructura Terciaria de Proteína
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