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1.
J Pediatr Gastroenterol Nutr ; 76(4): 447-450, 2023 04 01.
Artículo en Inglés | MEDLINE | ID: mdl-36580889

RESUMEN

A retrospective chart review was completed to examine psychological treatment duration and response among pediatric patients with a disorder of gut-brain interaction including functional abdominal pain and irritable bowel syndrome. Cognitive behavioral therapy (CBT) was delivered via telehealth with a licensed psychologist or supervised psychology trainee embedded in a pediatric gastroenterology clinic. Participants were 22 youth (mean age = 14.36 years) who received CBT via telehealth between February and September of 2021, after completing an initial evaluation between February and July of 2021. Patients completed reliable and valid self-report measures of functional disability and pain during treatment. A unique CBT model was employed with an initial focus on psychoeducation and function regardless of level of severity of functional impairment. Consistent with study hypotheses, nonparametric statistical analyses demonstrated statistically significant reductions in functional disability and pain following implementation of the CBT model via telehealth. Contrary to predictions, there was no relation found between severity of functional impairment and duration of treatment.


Asunto(s)
COVID-19 , Telemedicina , Adolescente , Humanos , Niño , Estudios Retrospectivos , Pandemias , Dolor Abdominal/etiología , Dolor Abdominal/terapia , Encéfalo , Resultado del Tratamiento
2.
Plant Physiol ; 185(4): 1559-1573, 2021 04 23.
Artículo en Inglés | MEDLINE | ID: mdl-33793956

RESUMEN

The presence of mixed-linkage (1,3;1,4)-ß-d-glucan (MLG) in plant cell walls is a key feature of grass species such as cereals, the main source of calorie intake for humans and cattle. Accumulation of this polysaccharide involves the coordinated regulation of biosynthetic and metabolic machineries. While several components of the MLG biosynthesis machinery have been identified in diverse plant species, degradation of MLG is poorly understood. In this study, we performed a large-scale forward genetic screen for maize (Zea mays) mutants with altered cell wall polysaccharide structural properties. As a result, we identified a maize mutant with increased MLG content in several tissues, including adult leaves and senesced organs, where only trace amounts of MLG are usually detected. The causative mutation was found in the GRMZM2G137535 gene, encoding a GH17 licheninase as demonstrated by an in vitro activity assay of the heterologously expressed protein. In addition, maize plants overexpressing GRMZM2G137535 exhibit a 90% reduction in MLG content, indicating that the protein is not only required, but its expression is sufficient to degrade MLG. Accordingly, the mutant was named MLG hydrolase 1 (mlgh1). mlgh1 plants show increased saccharification yields upon enzymatic digestion. Stacking mlgh1 with lignin-deficient mutations results in synergistic increases in saccharification. Time profiling experiments indicate that wall MLG content is modulated during day/night cycles, inversely associated with MLGH1 transcript accumulation. This cycling is absent in the mlgh1 mutant, suggesting that the mechanism involved requires MLG degradation, which may in turn regulate MLGH1 gene expression.


Asunto(s)
Pared Celular/metabolismo , Oscuridad , Glucanos/metabolismo , Hidrolasas/metabolismo , Hojas de la Planta/metabolismo , Polisacáridos/metabolismo , Zea mays/genética , Zea mays/metabolismo , Pared Celular/genética , Productos Agrícolas/genética , Productos Agrícolas/metabolismo , Regulación de la Expresión Génica de las Plantas , Genes de Plantas , Variación Genética , Genotipo , Glucanos/genética , Hidrolasas/genética , Mutación , Hojas de la Planta/genética , Polisacáridos/genética
3.
J Pediatr Gastroenterol Nutr ; 75(1): 52-55, 2022 07 01.
Artículo en Inglés | MEDLINE | ID: mdl-35621993

RESUMEN

Increased utilization of pediatric psychology services has been demonstrated following integration into urban pediatric gastroenterology clinics; however, examination within rural health systems is lacking. Utilization of pediatric psychology services was assessed through a retrospective analysis of Electronic Health Record data contrasting referrals occurring six months pre- and post-integration of pediatric psychology in an outpatient pediatric gastroenterology clinic within a rural setting. Significant increases in the number of referrals to pediatric psychology and number of billed initial visits were observed after integration, as was a significant decrease in time to be seen. Patients with public insurance were 3.1 times more likely to complete a billed initial visit compared with patients with nonpublic insurance. The current findings support the integration of pediatric psychology within rural outpatient pediatric gastroenterology clinics to increase utilization and allow more traditionally underserved families to benefit from these services.


Asunto(s)
Gastroenterología , Salud Rural , Niño , Humanos , Pacientes Ambulatorios , Psicología Infantil , Estudios Retrospectivos
4.
Dis Esophagus ; 35(10)2022 Oct 14.
Artículo en Inglés | MEDLINE | ID: mdl-35265973

RESUMEN

Eosinophilic Esophagitis (EoE) is an esophageal allergic inflammatory disorder triggered by food proteins. Symptoms of EoE are variable within and between individuals. Presenting symptoms may include dysphagia, food bolus impaction, dyspepsia, or more subtle symptoms such as feeding disorders, regurgitation sensation, or nausea. The development and validation of a pediatric EoE patient self-reported and parent proxy-reported outcome symptom scoring tool was created by Franciosi et al. published in BMJ 2011, titled the Pediatric Eosinophilic Esophagitis Symptom Score (PEESS™ v2.0). To date, its use is largely for research purposes. We propose to evaluate the implementation of the PEESS™ v2.0 in a prospective interventional controlled clinical practice. The study included 620 patients over an 18-month period. Surveys were delivered and administered digitally every month through the MyGeisinger.org Patient Portal. Our analysis demonstrated symptom severity and symptom frequency scores significantly improved over time. However, counter to our hypothesis, patients who completed the PEESS™v2.0 ultimately had higher EoE-related health care utilization of office visits and endoscopies compared with those who did not complete the PEESS™v2.0. This could be related to greater awareness of disease activity and/or increased willingness to seek care. Our study, in the context of mobile health tool and patient-reported outcome trends, represents an opportunity for improved disease monitoring at-home within the field of eosinophilic gastrointestinal diseases.


Asunto(s)
Trastornos de Deglución , Esofagitis Eosinofílica , Niño , Trastornos de Deglución/etiología , Enteritis , Eosinofilia , Esofagitis Eosinofílica/complicaciones , Esofagitis Eosinofílica/diagnóstico , Esofagitis Eosinofílica/terapia , Gastritis , Humanos , Náusea , Medición de Resultados Informados por el Paciente , Estudios Prospectivos
5.
FASEB J ; 33(2): 1711-1726, 2019 02.
Artículo en Inglés | MEDLINE | ID: mdl-30188757

RESUMEN

Sphingosine-1-phosphate (S1P) is involved in the regulation of important cellular processes, including immune-cell trafficking and proliferation. Altered S1P signaling is strongly associated with inflammation, cancer progression, and atherosclerosis; however, the mechanisms underlying its pathophysiologic effects are only partially understood. This study evaluated the effects of S1P in vitro and in vivo on the biosynthesis of leukotrienes (LTs), which form a class of lipid mediators involved in the pathogenesis of inflammatory diseases. Here, we report for the first time that S1P potently suppresses LT biosynthesis in Ca2+-ionophore-stimulated intact human neutrophils. S1P treatment resulted in intracellular Ca2+ mobilization, perinuclear translocation, and finally irreversible suicide inactivation of the LT biosynthesis key enzyme 5-lipoxygenase (5-LO). Agonist studies and S1P receptor mRNA expression analysis provided evidence for a S1P receptor 4-mediated effect, which was confirmed by a functional knockout of S1P4 in HL60 cells. Systemic administration of S1P in wild-type mice decreased both macrophage and neutrophil migration in the lungs in response to LPS and significantly attenuated 5-LO product formation, whereas these effects were abrogated in 5-LO or S1P4 knockout mice. In summary, targeting the 5-LO pathway is an important mechanism to explain S1P-mediated pathophysiologic effects. Furthermore, agonism at S1P4 represents a novel effective strategy in pharmacotherapy of inflammation.-Fettel, J., Kühn, B., Guillen, N. A., Sürün, D., Peters, M., Bauer, R., Angioni, C., Geisslinger, G., Schnütgen, F., Meyer zu Heringdorf, D., Werz, O., Meybohm, P., Zacharowski, K., Steinhilber, D., Roos, J., Maier, T. J. Sphingosine-1-phosphate (S1P) induces potent anti-inflammatory effects in vitro and in vivo by S1P receptor 4-mediated suppression of 5-lipoxygenase activity.


Asunto(s)
Antiinflamatorios/farmacología , Araquidonato 5-Lipooxigenasa/efectos de los fármacos , Lisofosfolípidos/farmacología , Receptores de Lisoesfingolípidos/fisiología , Esfingosina/análogos & derivados , Animales , Araquidonato 5-Lipooxigenasa/biosíntesis , Araquidonato 5-Lipooxigenasa/metabolismo , Ácido Araquidónico/metabolismo , Calcio/metabolismo , Línea Celular , Femenino , Humanos , Lisofosfolípidos/metabolismo , Ratones , Ratones Endogámicos C57BL , Neutrófilos/enzimología , Neutrófilos/metabolismo , Neumonía/metabolismo , Especies Reactivas de Oxígeno/metabolismo , Receptores de Lisoesfingolípidos/genética , Receptores de Lisoesfingolípidos/metabolismo , Transducción de Señal , Esfingosina/metabolismo , Esfingosina/farmacología , Especificidad por Sustrato
6.
Dis Esophagus ; 33(10)2020 Oct 12.
Artículo en Inglés | MEDLINE | ID: mdl-32696950

RESUMEN

Eosinophilic esophagitis (EoE) is an esophageal allergic inflammatory disorder often presenting with infant/toddler gastroesophageal reflux symptoms refractory to treatment, including acid suppression trials with histamine H2 antagonists and proton pump inhibitors. We propose to evaluate the impact of infant acid suppressant exposure in EoE. Geisinger's pediatric EoE cases were matched to controls (1:5 EoE case control ratio) using age, race, sex, and ages at other diagnoses of asthma, eczema, and environmental allergies, totaling 526 EoE cases and 2,630 controls. Comparisons between EoE cases and matched controls were tested with regard to rates of acid suppression use with H2 antagonists and PPIs during infancy. Our analyses found the use of acid suppression in infancy was positively associated with EoE: PPI (5.7% EoE cases vs. 1.6% controls; P < 0.0001), H2 antagonists (8.8% EoE cases vs. 4.5% controls; P < 0.0001). Additionally, analysis of EoE cases using acid suppression during infancy indicated a likelihood for the diagnosis with EoE at an earlier age. Early acid suppression use in infants is significantly associated with the diagnosis of EoE in childhood in this well-matched retrospective cohort study. The potential link warrants additional investigation. Our study further reinforces the evidence-based stewardship of acid suppressant use, especially in our most vulnerable populations.


Asunto(s)
Esofagitis Eosinofílica , Estudios de Casos y Controles , Niño , Esofagitis Eosinofílica/tratamiento farmacológico , Esofagitis Eosinofílica/epidemiología , Antagonistas de los Receptores H2 de la Histamina/uso terapéutico , Humanos , Lactante , Inhibidores de la Bomba de Protones/efectos adversos , Estudios Retrospectivos
7.
Rapid Commun Mass Spectrom ; 33 Suppl 1: 40-49, 2019 May.
Artículo en Inglés | MEDLINE | ID: mdl-29964304

RESUMEN

RATIONALE: Matrix-assisted laser desorption/ionization mass spectrometry (MALDI-MS) analysis of covalent 5-lipoxygenase inhibitors is challenging due to unknown amino acid specificity and low posttranslational modification (PTM)-identification rates. The analysis of the amino-acid specificity and of the characteristic fragmentation of chemically modified peptides is considered to improve knowledge for the analysis of chemically modified peptides and proteins by MALDI-MS. METHODS: Various compounds were used to investigate the modification of synthetic peptides carrying reactive amino acid residues. Mass spectra were recorded using a MALDI-LTQ Orbitrap XL for high-resolution mass spectrometry and ion trap MALDI-MS2 . UV-Vis-based reduction and radical scavenging analysis was conducted. The on-plate digestion method described by Rühl et al was utilized for modification-site analysis at 5-lipoxygenase. RESULTS: The analysis of amino-acid-specific reactivity revealed the reactivity of quinones towards cysteine residues and the potential occurrence of a subsequent oxidative process was observed by an UV-Vis-based reduction assay. MALDI collision-induced dissociation tandem mass spectrometry (CID-MS2 ) indicated a prominent fragmentation mechanism of modified cysteine and histidine residues. Fragmentation included highly abundant neutral-loss signals which could be used to identify new modifications induced by chemical modifiers at the cysteine-159 residue of 5-lipoxygenase. CONCLUSIONS: Specificity and fragmentation analysis provides crucial information for the analysis of chemically modified cysteines and histidines by MALDI-MS. Elucidation of binding sites by MALDI-MS has been significantly improved using an easy-to-run peptide assay and gives background information for the analysis in the case of chemically modified 5-lipoxygenase.


Asunto(s)
Péptidos/química , Proteínas/química , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción/métodos , Espectrometría de Masas en Tándem/métodos , Sitios de Unión , Cisteína/análisis , Cisteína/química , Cisteína/metabolismo , Histidina/análisis , Histidina/química , Histidina/metabolismo , Lipooxigenasa , Inhibidores de la Lipooxigenasa , Fragmentos de Péptidos/análisis , Fragmentos de Péptidos/química , Péptidos/análisis , Péptidos/metabolismo , Unión Proteica , Proteínas/análisis , Proteínas/metabolismo , Quinonas/química
8.
J Biol Chem ; 291(10): 5385-95, 2016 Mar 04.
Artículo en Inglés | MEDLINE | ID: mdl-26742840

RESUMEN

Flavonols are a group of secondary metabolites that affect diverse cellular processes. They are considered putative negative regulators of the transport of the phytohormone auxin, by which they influence auxin distribution and concomitantly take part in the control of plant organ development. Flavonols are accumulating in a large number of glycosidic forms. Whether these have distinct functions and diverse cellular targets is not well understood. The rol1-2 mutant of Arabidopsis thaliana is characterized by a modified flavonol glycosylation profile that is inducing changes in auxin transport and growth defects in shoot tissues. To determine whether specific flavonol glycosides are responsible for these phenotypes, a suppressor screen was performed on the rol1-2 mutant, resulting in the identification of an allelic series of UGT89C1, a gene encoding a flavonol 7-O-rhamnosyltransferase. A detailed analysis revealed that interfering with flavonol rhamnosylation increases the concentration of auxin precursors and auxin metabolites, whereas auxin transport is not affected. This finding provides an additional level of complexity to the possible ways by which flavonols influence auxin distribution and suggests that flavonol glycosides play an important role in regulating plant development.


Asunto(s)
Proteínas de Arabidopsis/metabolismo , Arabidopsis/metabolismo , Flavonoles/metabolismo , Glucosiltransferasas/metabolismo , Hexosiltransferasas/metabolismo , Ácidos Indolacéticos/metabolismo , Secuencia de Aminoácidos , Arabidopsis/genética , Arabidopsis/crecimiento & desarrollo , Proteínas de Arabidopsis/química , Proteínas de Arabidopsis/genética , Secuencia de Bases , Glucosiltransferasas/genética , Hexosiltransferasas/química , Hexosiltransferasas/genética , Homeostasis , Datos de Secuencia Molecular , Desarrollo de la Planta , Ramnosa/metabolismo
9.
Plant J ; 84(1): 202-15, 2015 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-26315512

RESUMEN

The wheat gene Lr34 encodes an ABCG-type transporter which provides durable resistance against multiple pathogens. Lr34 is functional as a transgene in barley, but its mode of action has remained largely unknown both in wheat and barley. Here we studied gene expression in uninfected barley lines transgenic for Lr34. Genes from multiple defense pathways contributing to basal and inducible disease resistance were constitutively active in seedlings and mature leaves. In addition, the hormones jasmonic acid and salicylic acid were induced to high levels, and increased levels of lignin as well as hordatines were observed. These results demonstrate a strong, constitutive re-programming of metabolism by Lr34. The resistant Lr34 allele (Lr34res) encodes a protein that differs by two amino acid polymorphisms from the susceptible Lr34sus allele. The deletion of a single phenylalanine residue in Lr34sus was sufficient to induce the characteristic Lr34-based responses. Combination of Lr34res and Lr34sus in the same plant resulted in a reduction of Lr34res expression by 8- to 20-fold when the low-expressing Lr34res line BG8 was used as a parent. Crosses with the high-expressing Lr34res line BG9 resulted in an increase of Lr34sus expression by 13- to 16-fold in progenies that inherited both alleles. These results indicate an interaction of the two Lr34 alleles on the transcriptional level. Reduction of Lr34res expression in BG8 crosses reduced the negative pleiotropic effects of Lr34res on barley growth and vigor without compromising disease resistance, suggesting that transgenic combination of Lr34res and Lr34sus can result in agronomically useful resistance.


Asunto(s)
Resistencia a la Enfermedad/genética , Hordeum/metabolismo , Hordeum/fisiología , Triticum/metabolismo , Triticum/fisiología , Hordeum/genética , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Plantas Modificadas Genéticamente/genética , Plantas Modificadas Genéticamente/metabolismo , Triticum/genética
10.
BMC Plant Biol ; 15: 155, 2015 Jun 24.
Artículo en Inglés | MEDLINE | ID: mdl-26099801

RESUMEN

BACKGROUND: Leucine-rich repeat extensins (LRXs) are extracellular proteins consisting of an N-terminal leucine-rich repeat (LRR) domain and a C-terminal extensin domain containing the typical features of this class of structural hydroxyproline-rich glycoproteins (HRGPs). The LRR domain is likely to bind an interaction partner, whereas the extensin domain has an anchoring function to insolubilize the protein in the cell wall. Based on the analysis of the root hair-expressed LRX1 and LRX2 of Arabidopsis thaliana, LRX proteins are important for cell wall development. The importance of LRX proteins in non-root hair cells and on the structural changes induced by mutations in LRX genes remains elusive. RESULTS: The LRX gene family of Arabidopsis consists of eleven members, of which LRX3, LRX4, and LRX5 are expressed in aerial organs, such as leaves and stem. The importance of these LRX genes for plant development and particularly cell wall formation was investigated. Synergistic effects of mutations with gradually more severe growth retardation phenotypes in double and triple mutants suggest a similar function of the three genes. Analysis of cell wall composition revealed a number of changes to cell wall polysaccharides in the mutants. CONCLUSIONS: LRX3, LRX4, and LRX5, and most likely LRX proteins in general, are important for cell wall development. Due to the complexity of changes in cell wall structures in the lrx mutants, the exact function of LRX proteins remains to be determined. The increasingly strong growth-defect phenotypes in double and triple mutants suggests that the LRX proteins have similar functions and that they are important for proper plant development.


Asunto(s)
Proteínas de Arabidopsis/genética , Arabidopsis/crecimiento & desarrollo , Arabidopsis/genética , Pared Celular/metabolismo , Regulación de la Expresión Génica de las Plantas , Glicoproteínas/genética , Leucina/metabolismo , Secuencia de Aminoácidos , Proteínas de Arabidopsis/metabolismo , Glicoproteínas/metabolismo , Datos de Secuencia Molecular , Alineación de Secuencia
11.
J Thromb Haemost ; 22(3): 686-699, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38072376

RESUMEN

BACKGROUND: A safe and efficacious hemostatic product with a long shelf-life is needed to reduce mortality from hemorrhage due to trauma and improve surgical outcomes for persons with platelet deficiency or dysfunction. Thrombosomes, a trehalose-stabilized, leukoreduced, pooled blood group-O freeze-dried platelet-derived hemostatic (FPH) with a 3-year shelf-life, may satisfy this need. OBJECTIVES: To characterize the mechanism of action of FPH. METHODS: FPH's ability to adhere to collagen, aggregate with and without platelets, and form clots was evaluated in vitro. Nonobese diabetic-severe combined immunodeficiency mouse models were used to assess circulation persistence and hemostatic efficacy. RESULTS: FPH displays the morphology and surface proteins of activated platelets. FPH adheres to collagen, aggregates, and promotes clots, producing an insoluble fibrin mesh. FPH is rapidly cleared from circulation, has hemostatic efficacy comparable to apheresis platelets in a murine tail-cut, and acts in a dose-dependent manner. CONCLUSION: FPH is a first-in-class investigational treatment and shows strong potential as a hemostatic agent that is capable of binding exposed collagen, coaggregating with endogenous platelets, and promoting the coagulation cascade. These properties may be exploited to treat active platelet-related or diffuse vascular bleeding. FPH has the potential to fulfill a large unmet patient need as an acute hemostatic treatment in severe bleeding, such as surgery and trauma.


Asunto(s)
Hemostáticos , Trombosis , Humanos , Animales , Ratones , Hemostáticos/farmacología , Hemostasis , Plaquetas/metabolismo , Coagulación Sanguínea , Hemorragia/metabolismo , Colágeno/metabolismo , Trombosis/metabolismo
12.
PLoS One ; 19(6): e0304603, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38870196

RESUMEN

Iatrogenic transmission of prions, the infectious agents of fatal Creutzfeldt-Jakob disease, through inefficiently decontaminated medical instruments remains a critical issue. Harsh chemical treatments are effective, but not suited for routine reprocessing of reusable surgical instruments in medical cleaning and disinfection processes due to material incompatibilities. The identification of mild detergents with activity against prions is therefore of high interest but laborious due to the low throughput of traditional assays measuring prion infectivity. Here, we report the establishment of TESSA (sTainlESs steel-bead Seed Amplification assay), a modified real-time quaking induced cyclic amplification (RT-QuIC) assay that explores the propagation activity of prions with stainless steel beads. TESSA was applied for the screening of about 70 different commercially available and novel formulations and conditions for their prion inactivation efficacy. One hypochlorite-based formulation, two commercially available alkaline formulations and a manual alkaline pre-cleaner were found to be highly effective in inactivating prions under conditions simulating automated washer-disinfector cleaning processes. The efficacy of these formulations was confirmed in vivo in a murine prion infectivity bioassay, yielding a reduction of the prion titer for bead surface adsorbed prions below detectability. Our data suggest that TESSA represents an effective method for a rapid screening of prion-inactivating detergents, and that alkaline and oxidative formulations are promising in reducing the risk of potential iatrogenic prion transmission through insufficiently decontaminated instrument surfaces.


Asunto(s)
Priones , Acero Inoxidable , Instrumentos Quirúrgicos , Animales , Ratones , Acero Inoxidable/química , Descontaminación/métodos , Síndrome de Creutzfeldt-Jakob/transmisión , Síndrome de Creutzfeldt-Jakob/prevención & control , Desinfección/métodos , Detergentes/química , Detergentes/farmacología , Humanos , Desinfectantes/farmacología , Oxidación-Reducción
13.
Thromb Res ; 238: 67-77, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38678865

RESUMEN

INTRODUCTION: A freeze-dried, platelet-derived hemostatic agent (FPH) was developed for acute hemorrhage. The canine product (cFPH) was developed for use in preclinical models supporting human product (hFPH) investigations. MATERIALS AND METHODS: A carotid artery bypass graft (CABG) study in dogs compared 3 dosages of cFPH to canine liquid stored platelets (cLSP) and vehicle (VEH) control groups. Histopathological analysis and blood loss assessments were completed. A separate ex-vivo synthetic graft study assessed thrombogenicity via blood from human and canine donors that was combined with species-specific FPH or apheresis platelets. Characterization of cFPH and hFPH included thrombin generation, total thrombus formation, and scanning electron microscopy. RESULTS: Blood loss was reduced in CABG dogs receiving standard of care (cLSP) or cFPH treatment compared to VEH control; a cFPH dose effect signal was observed. Further, cFPH dosing up to 5 × 109 cells/kg was not associated with increased mortality or occlusion of the anastomosis sites, and histopathologic evidence of off-target thrombosis was not detected. When passed through a synthetic graft (ex vivo), whole blood combined with species-specific FPH did not result in thrombosis beyond that of whole blood control. In vitro testing and imaging of cFPH and FPH were comparable. CONCLUSIONS: A single dose of cFPH or cLSP reduced blood loss in a pilot surgical study and was well tolerated with no related adverse events. Further, the hemostatic activity and characteristics of cFPH are comparable to that of hFPH, suggesting that research findings from the canine product are likely to inform the development of the human product.


Asunto(s)
Plaquetas , Liofilización , Hemorragia , Hemostáticos , Perros , Animales , Hemostáticos/uso terapéutico , Hemostáticos/farmacología , Humanos , Modelos Animales de Enfermedad , Masculino , Pérdida de Sangre Quirúrgica/prevención & control , Femenino
14.
J Trauma Acute Care Surg ; 96(3): 364-370, 2024 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-38011031

RESUMEN

BACKGROUND: Hemorrhage accounts for the most preventable deaths after trauma. Resuscitation is guided by studies that demonstrate improved outcomes in patients receiving whole blood or balanced administration of blood products. Platelets present a logistical challenge due to short shelf life and need for refrigeration. Platelet-derived extracellular vesicles (PEVs) are a possible platelet alternative. Platelet-derived extracellular vesicles are secreted from platelets, have hemostatic effects and mitigate inflammation and vascular injury, similar to platelets. This pilot study aimed to elucidate the therapeutic effects of PEVs in a rat model of uncontrolled hemorrhage. METHODS: Male rats were anesthetized and femoral vessels cannulated. Vital signs (MAP, HR, and RR) were monitored. Electrolytes, lactate and ABG were obtained at baseline, 1-hour and 3-hours post injury. Laparotomy was performed, 50% of the middle hepatic lobe excised and the abdomen packed with gauze. Rats received 2 mL PEVs or lactated Ringers (LR) over 6 minutes immediately after injury. Peritoneal blood loss was quantified using preweighed gauze at 5 minutes, 15 minutes, 30 minutes, 45 minutes, and 60 minutes. Laparotomy was closed 1-hour postinjury. Animals were monitored for 3 hours postinjury then euthanized. Generalized Linear Mixed Effects models were performed to assess effects of treatment and time on lactate and MAP. RESULTS: Twenty-one rats were included (11 LR, 10 PEV). Overall blood loss was between 6 mL and 10 mL and not significantly different between groups. There was a 36% mortality rate in the LR group and 0% mortality in the PEV group ( p = 0.03). The LR group had significantly higher lactates at 1 hour ( p = 0.025). At 15 minutes, 45 minutes, 60 minutes, and 180 minutes, the MAP of the PEV group was significantly higher than the LR group. CONCLUSION: Early studies are encouraging regarding the potential use of PEVs in uncontrolled hemorrhagic shock based on improved survival and hemodynamics.


Asunto(s)
Vesículas Extracelulares , Choque Hemorrágico , Humanos , Ratas , Masculino , Animales , Choque Hemorrágico/tratamiento farmacológico , Proyectos Piloto , Hemorragia/tratamiento farmacológico , Resucitación , Ácido Láctico , Soluciones Isotónicas/farmacología , Soluciones Isotónicas/uso terapéutico , Modelos Animales de Enfermedad
15.
Front Plant Sci ; 14: 1099009, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36959947

RESUMEN

The development of efficient pipelines for the bioconversion of grass lignocellulosic feedstocks is challenging due to the limited understanding of the molecular mechanisms controlling the synthesis, deposition, and degradation of the varying polymers unique to grass cell walls. Here, we describe a large-scale forward genetic approach resulting in the identification of a collection of chemically mutagenized maize mutants with diverse alterations in their cell wall attributes such as crystalline cellulose content or hemicellulose composition. Saccharification yield, i.e. the amount of lignocellulosic glucose (Glc) released by means of enzymatic hydrolysis, is increased in two of the mutants and decreased in the remaining six. These mutants, termed candy-leaf (cal), show no obvious plant growth or developmental defects despite associated differences in their lignocellulosic composition. The identified cal mutants are a valuable tool not only to understand recalcitrance of grass lignocellulosics to enzymatic deconstruction but also to decipher grass-specific aspects of cell wall biology once the genetic basis, i.e. the location of the mutation, has been identified.

16.
Plant Physiol ; 156(2): 585-95, 2011 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-21502189

RESUMEN

Flavonoids represent a class of secondary metabolites with diverse functions in plants including ultraviolet protection, pathogen defense, and interspecies communication. They are also known as modulators of signaling processes in plant and animal systems and therefore are considered to have beneficial effects as nutraceuticals. The rol1-2 (for repressor of lrx1) mutation of Arabidopsis (Arabidopsis thaliana) induces aberrant accumulation of flavonols and a cell-growth phenotype in the shoot. The hyponastic cotyledons, aberrant shape of pavement cells, and deformed trichomes in rol1-2 mutants are suppressed by blocking flavonoid biosynthesis, suggesting that the altered flavonol accumulation in these plants induces the shoot phenotype. Indeed, the identification of several transparent testa, myb, and fls1 (for flavonol synthase1) alleles in a rol1-2 suppressor screen provides genetic evidence that flavonols interfere with shoot development in rol1-2 seedlings. The increased accumulation of auxin in rol1-2 seedlings appears to be caused by a flavonol-induced modification of auxin transport. Quantification of auxin export from mesophyll protoplasts revealed that naphthalene-1-acetic acid but not indole-3-acetic acid transport is affected by the rol1-2 mutation. Inhibition of flavonol biosynthesis in rol1-2 fls1-3 restores naphthalene-1-acetic acid transport to wild-type levels, indicating a very specific mode of action of flavonols on the auxin transport machinery.


Asunto(s)
Arabidopsis/metabolismo , Flavonoles/metabolismo , Ácidos Indolacéticos/metabolismo , Alelos , Arabidopsis/citología , Proteínas de Arabidopsis/metabolismo , Transporte Biológico , Vías Biosintéticas , Forma de la Célula , Cotiledón/citología , Cotiledón/metabolismo , Difusión , Prueba de Complementación Genética , Proteínas Fluorescentes Verdes/metabolismo , Células del Mesófilo/citología , Células del Mesófilo/metabolismo , Mutación/genética , Fenotipo , Protoplastos/citología , Protoplastos/metabolismo , Proteínas Recombinantes de Fusión/metabolismo , Supresión Genética
17.
J Pediatr Gastroenterol Nutr ; 55(1): 32-43, 2012 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-22197944

RESUMEN

OBJECTIVES: Genotypic variation in signal transducer and activator of transcription 3 (STAT3) increases risk for inflammatory bowel disease (IBD), and STAT3-dependent inflammatory networks are induced in the colon in these patients. We hypothesized that STAT3 "A" risk allele carriage would be associated with increased cellular STAT3 activation and colon leukocyte recruitment. METHODS: Colonic expression of genes regulating STAT3 signaling and leukocyte recruitment and function was measured in pediatric patients with Crohn disease (CD) stratified by STAT3 genotype. The frequency of colonic pSTAT3* and CXCR2* neutrophils was determined using immunohistochemistry. STAT3 tyrosine phosphorylation (pSTAT3) was measured in circulating leukocytes by flow cytometry, and mechanisms regulating STAT3 activation were tested in IBD Epstein-Barr virus (EBV)-transformed lymphocytes (EBL). RESULTS: Colonic expression of interleukin 6 (IL-6), the STAT3 target gene SOCS3, the neutrophil chemoattractants IL-8, CXCL1, and CXCL3, and the neutrophil products S100A8, S100A9, and S100A12 were increased in patients carrying the STAT3 "A" risk allele. The frequency of neutrophils expressing the cognate receptor for IL-8, CXCR2, was increased in colonic biopsies from patients carrying the risk allele, and the frequency of pSTAT3* or CXCR2* neutrophils correlated with histologic severity. The frequency of CD4 lymphocytes and granulocytes expressing pSTAT3 was increased in patients carrying the STAT3 "A" risk allele. EBLs from patients carrying the STAT3 "A" risk allele exhibited increased basal and IL-6-stimulated STAT3 tyrosine phosphorylation, increased transcription of STAT3 and SOCS3 after IL-6 stimulation, and increased membrane localization of the IL-6 receptor, GP130, and Janus-associated kinase 2. CONCLUSIONS: The STAT3 "A" risk allele is associated with increased cellular STAT3 activation and upregulation of pathways that promote recruitment of CXCR2* neutrophils to the gut.


Asunto(s)
Colon/metabolismo , Enfermedad de Crohn/genética , Enfermedad de Crohn/metabolismo , Neutrófilos/metabolismo , Factor de Transcripción STAT3/genética , Transducción de Señal/genética , Adolescente , Alelos , Linfocitos B/metabolismo , Linfocitos T CD4-Positivos , Calgranulina A/metabolismo , Calgranulina B/metabolismo , Células Cultivadas , Quimiocina CXCL1/metabolismo , Quimiocinas CXC/genética , Quimiocinas CXC/metabolismo , Niño , Colon/inmunología , Colon/patología , Enfermedad de Crohn/patología , Femenino , Expresión Génica , Variación Genética , Genotipo , Humanos , Interleucina-1/metabolismo , Interleucina-6/genética , Interleucina-6/metabolismo , Interleucina-8/genética , Interleucina-8/metabolismo , Janus Quinasa 2/metabolismo , Recuento de Linfocitos , Masculino , Fosforilación , Polimorfismo de Nucleótido Simple , Receptores de Interleucina-8B/metabolismo , Proteínas S100/metabolismo , Proteína S100A12 , Factor de Transcripción STAT3/metabolismo , Proteína 3 Supresora de la Señalización de Citocinas , Proteínas Supresoras de la Señalización de Citocinas/genética , Proteínas Supresoras de la Señalización de Citocinas/metabolismo , Tirosina/metabolismo , Regulación hacia Arriba
18.
Cells ; 10(3)2021 03 19.
Artículo en Inglés | MEDLINE | ID: mdl-33808926

RESUMEN

Plant cells are encapsulated by cell walls whose properties largely determine cell growth. We have previously identified the rol1-2 mutant, which shows defects in seedling root and shoot development. rol1-2 is affected in the Rhamnose synthase 1 (RHM1) and shows alterations in the structures of Rhamnogalacturonan I (RG I) and RG II, two rhamnose-containing pectins. The data presented here shows that root tissue of the rol1-2 mutant fails to properly differentiate the cell wall in cell corners and accumulates excessive amounts of callose, both of which likely alter the physical properties of cells. A surr (suppressor of the rol1-2 root developmental defect) mutant was identified that alleviates the cell growth defects in rol1-2. The cell wall differentiation defect is re-established in the rol1-2 surr mutant and callose accumulation is reduced compared to rol1-2. The surr mutation is an allele of the cyclin-dependent kinase 8 (CDK8), which encodes a component of the mediator complex that influences processes central to plant growth and development. Together, the identification of the surr mutant suggests that changes in cell wall composition and turnover in the rol1-2 mutant have a significant impact on cell growth and reveals a function of CDK8 in cell wall architecture and composition.


Asunto(s)
Proteínas de Arabidopsis/metabolismo , Arabidopsis/genética , Arabidopsis/metabolismo , Diferenciación Celular/fisiología , Quinasa 8 Dependiente de Ciclina/metabolismo , Proteínas de Arabidopsis/genética , Pared Celular/metabolismo , Quinasa 8 Dependiente de Ciclina/genética , Raíces de Plantas/genética , Ramnosa/análisis , Plantones/genética
19.
Front Pharmacol ; 11: 1297, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-33013366

RESUMEN

Nitro fatty acids (NFAs) are endogenously generated lipid mediators deriving from reactions of unsaturated electrophilic fatty acids with reactive nitrogen species. Furthermore, Mediterranean diets can be a source of NFA. These highly electrophilic fatty acids can undergo Michael addition reaction with cysteine residues, leading to post-translational modifications (PTM) of selected regulatory proteins. Such modifications are capable of changing target protein function during cell signaling or in biosynthetic pathways. NFA target proteins include the peroxisome proliferator-activated receptor γ (PPAR-γ), the pro-inflammatory and tumorigenic nuclear factor-κB (NF-κB) signaling pathway, the pro-inflammatory 5-lipoxygenases (5-LO) biosynthesis pathway as well as soluble epoxide hydrolase (sEH), which is essentially involved in the regulation of vascular tone. In several animal models of inflammation and cancer, the therapeutic efficacy of well-tolerated NFA has been demonstrated. This has already led to clinical phase II studies investigating possible therapeutic effects of NFA in subjects with pulmonary arterial hypertension. Albeit Michael acceptors feature a broad spectrum of bioactivity, they have for a rather long time been avoided as drug candidates owing to their presumed unselective reactivity and toxicity. However, targeted covalent modification of regulatory proteins by Michael acceptors became recognized as a promising approach to drug discovery with the recent FDA approvals of the cancer therapeutics, afatanib (2013), ibrutinib (2013), and osimertinib (2015). Furthermore, the Michael acceptor, neratinib, a dual inhibitor of the human epidermal growth factor receptor 2 and epidermal growth factor receptor, was recently approved by the FDA (2017) and by the EMA (2018) for the treatment of breast cancer. Finally, a number of further Michael acceptor drug candidates are currently under clinical investigation for pharmacotherapy of inflammation and cancer. In this review, we focus on the pharmacology of NFA and other Michael acceptor drugs, summarizing their potential as an emerging class of future antiphlogistics and adjuvant in tumor therapeutics.

20.
Biochem Pharmacol ; 155: 48-60, 2018 09.
Artículo en Inglés | MEDLINE | ID: mdl-29909078

RESUMEN

Nitro-fatty acids (NFAs) are endogenously occurring lipid mediators exerting strong anti-inflammatory effects and acting as anti-oxidants in a number of animal models of inflammation. These NFA effects are mediated by targeting important regulatory proteins involved in inflammatory processes, such as 5-lipoxygenase, soluble epoxide hydrolase, or NF-κB. In the present study, we investigated the anti-tumorigenic effects of NFAs on colorectal cancer (CRC) cells in cell culture-based experiments and in a murine xenograft model of human CRC. We could show that 9-NOA suppresses the viability of CRC cells (HCT-116 and HT-29) by inducing a caspase-dependent apoptosis via the intrinsic apoptotic pathway. Co-treatment with the pan-caspase inhibitor Q-VD-OPH counteracted the NFA-mediated apoptosis in both cell lines. Furthermore, NFAs affected the cell cycle transition and reduced the oxygen consumption rate (OCR) immediately. On the contrary to their well-known anti-oxidative properties, NFAs mediated the generation of mitochondrial oxidative stress in human CRC cells. Additionally, similar to the cytostatic drug mitomycin, 9-NOA significantly reduced tumor growth in a murine xenograft model of human colorectal cancer. In contrast to the established cytostatic drug, 9-NOA treatment was well tolerated by mice. This study delivers a novel mechanistic approach for nitro-fatty acid-induced inhibition of CRC cell growth by targeting mitochondrial functions such as the mitochondrial membrane potential and mitochondrial respiration. We suggest these naturally occurring lipid mediators as a new class of well tolerated chemotherapeutic drug candidates for treatment of CRC or potentially other inflammation-driven cancer types.


Asunto(s)
Antiinflamatorios/metabolismo , Apoptosis/fisiología , Proliferación Celular/fisiología , Neoplasias Colorrectales/metabolismo , Ácidos Grasos/metabolismo , Mitocondrias/metabolismo , Animales , Antiinflamatorios/farmacología , Apoptosis/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Ácidos Grasos/farmacología , Células HCT116 , Células HEK293 , Células HT29 , Humanos , Masculino , Ratones , Ratones Endogámicos ICR , Mitocondrias/efectos de los fármacos
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