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1.
J Nutr ; 154(3): 908-920, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38253226

RESUMEN

BACKGROUND: Medium-chain fatty acids (MCFAs) are commonly used to enhance the caloric content of infant formulas. We previously reported that pigs fed MCFA developed hepatic steatosis when compared to those fed isocaloric long-chain fatty acid (LCFA) rich formula. OBJECTIVES: The objectives of this study were to investigate: 1) whether MCFA and LCFA feeding affect hepatic fatty acid oxidation, and 2) how fat type alters the expression of hepatic fatty acid metabolic genes. METHODS: Twenty-six, 7-d-old pigs were fed a low-energy control (CONT) formula, or 2 isocaloric high-energy formulas rich in LCFA or MCFA for 22 days. Livers were collected for examining ex vivo fatty acid oxidation, fatty acid content, and mRNA expression of fatty acid metabolic genes. RESULTS: Liver fat was 20% for pigs in the MCFA compared with 2.9% and 4.6% for those in the CONT and LCFA groups (P < 0.05). MCFA-fed pigs had greater amounts of hepatic laurate, myristate, palmitate, and palmitoleate (14, 34, 49, and 9.3 mg · g-1) than those fed LCFA and CONT (1.8, 1.9, 19, 1.5 mg · g-1) formulas (P ≤ 0.05). Hepatic laurate and palmitate oxidation was reduced for pigs fed MCFA (29 mmol · mg-1 · h-1) compared with those fed CONT (54 mmol · mg-1 · h-1) and LCFA (51 mmol · mg-1 · h-1) formulas (P < 0.05). Expression of fatty acid synthase 3 (FASN-3), fatty acid binding protein 1 (FABP-1), and acetyl-CoA carboxylase 1 (ACACA-1) were 8-, 6-, and 2-fold greater for pigs in the MCFA than those in the LCFA and CONT groups (P < 0.05). CONCLUSIONS: Feeding MCFA resulted in hepatic steatosis compared with an isocaloric formula rich in LCFA. Steatosis occurred concomitantly with reduced fatty acid oxidation but greater mRNA expression of fatty acid synthetic and catabolic genes.


Asunto(s)
Hígado Graso , Lauratos , Humanos , Recién Nacido , Animales , Porcinos , Lauratos/metabolismo , Ácidos Grasos/metabolismo , Hígado/metabolismo , Hígado Graso/etiología , Hígado Graso/veterinaria , Hígado Graso/metabolismo , ARN Mensajero/genética , ARN Mensajero/metabolismo , Palmitatos/metabolismo
2.
Biophys J ; 122(21): 4288-4302, 2023 11 07.
Artículo en Inglés | MEDLINE | ID: mdl-37803830

RESUMEN

DNA in sperm undergoes an extreme compaction to almost crystalline packing levels. To produce this dense packing, DNA is dramatically reorganized in minutes by protamine proteins. Protamines are positively charged proteins that coat negatively charged DNA and fold it into a series of toroids. The exact mechanism for forming these ∼50-kbp toroids is unknown. Our goal is to study toroid formation by starting at the "bottom" with folding of short lengths of DNA that form loops and working "up" to more folded structures that occur on longer length scales. We previously measured folding of 200-300 bp of DNA into a loop. Here, we look at folding of intermediate DNA lengths (L = 639-3003 bp) that are 2-10 loops long. We observe two folded structures besides loops that we hypothesize are early intermediates in the toroid formation pathway. At low protamine concentrations (∼0.2 µM), we see that the DNA folds into flowers (structures with multiple loops that are positioned so they look like the petals of a flower). Folding at these concentrations condenses the DNA to 25% of its original length, takes seconds, and is made up of many small bending steps. At higher protamine concentrations (≥2 µM), we observe a second folded structure-the loop stack-where loops are stacked vertically one on top of another. These results lead us to propose a two-step process for folding at this length scale: 1) protamine binds to DNA, bending it into loops and flowers, and 2) flowers collapse into loop stacks. These results highlight how protamine uses a bind-and-bend mechanism to rapidly fold DNA, which may be why protamine can fold the entire sperm genome in minutes.


Asunto(s)
Protaminas , Semillas , Protaminas/química , Protaminas/metabolismo , Semillas/metabolismo , ADN/química , Espermatozoides/metabolismo , Flores/metabolismo
3.
Cleft Palate Craniofac J ; 60(3): 359-366, 2023 03.
Artículo en Inglés | MEDLINE | ID: mdl-35244480

RESUMEN

Oronasal fistula (ONF) is a common complication encountered after palatoplasty. Repair is indicated when symptoms impact speech and swallowing. In spite of the variety of surgical approaches described to repair these defects, recurrence rates remain high. Traditionally, successful closure is said to be achieved in using a double-layered approach due to the three-dimensional aspect of the defect. The extent of the fistula into the nasal cavity has incited an increased curiosity in using local endonasal flaps. In recent years, endonasal reconstructive procedures have seen increased interest and application, from cranial base defect repairs to orbital reconstruction and beyond. The nasoseptal (NSF) and inferior turbinate flaps (ITF) possess a robust arterial supply and an exceptional reach with excellent results demonstrated in large defect repair. However, the use of these flaps in ONF repair is scarcely discussed in the literature, and their effectiveness is relatively undetermined. In this manuscript, we present a series of three patients who underwent a triple layer ONF closure, with the oral portion incorporating a turn-in mucosal flap plus a local palate rotation flap or greater palatine artery pedicled-rotation flap, and a NSF or an ITF for the nasal portion of the defect.


Asunto(s)
Fístula , Enfermedades Nasales , Procedimientos de Cirugía Plástica , Humanos , Fístula/cirugía , Nariz/cirugía , Enfermedades Nasales/cirugía , Fístula Oral/cirugía , Colgajos Quirúrgicos
4.
Nucleic Acids Res ; 48(11): 6108-6119, 2020 06 19.
Artículo en Inglés | MEDLINE | ID: mdl-32392345

RESUMEN

Protamine proteins dramatically condense DNA in sperm to almost crystalline packing levels. Here, we measure the first step in the in vitro pathway, the folding of DNA into a single loop. Current models for DNA loop formation are one-step, all-or-nothing models with a looped state and an unlooped state. However, when we use a Tethered Particle Motion (TPM) assay to measure the dynamic, real-time looping of DNA by protamine, we observe the presence of multiple folded states that are long-lived (∼100 s) and reversible. In addition, we measure folding on DNA molecules that are too short to form loops. This suggests that protamine is using a multi-step process to loop the DNA rather than a one-step process. To visualize the DNA structures, we used an Atomic Force Microscopy (AFM) assay. We see that some folded DNA molecules are loops with a ∼10-nm radius and some of the folded molecules are partial loops-c-shapes or s-shapes-that have a radius of curvature of ∼10 nm. Further analysis of these structures suggest that protamine is bending the DNA to achieve this curvature rather than increasing the flexibility of the DNA. We therefore conclude that protamine loops DNA in multiple steps, bending it into a loop.


Asunto(s)
ADN/química , ADN/efectos de los fármacos , Conformación de Ácido Nucleico/efectos de los fármacos , Protaminas/química , Protaminas/farmacología , ADN/ultraestructura , Microscopía de Fuerza Atómica , Docilidad
5.
Am J Otolaryngol ; 43(2): 103304, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-34896938

RESUMEN

OBJECTIVE: There is a void in the literature describing reliable surgical landmarks that aid in the dissection of the facial recess in the absence of skeletonizing the mastoid segment of the facial nerve. The posterior ligament of the incus is a readily distinguishable "white dot" along the incus buttress that has been used to guide dissection in a safe and efficient manner. The goal of our study is to describe a surgical approach that utilizes this surgical landmark to drill the facial recess and to take anatomical measurements demonstrating the safety and reliability of this approach. MATERIALS AND METHODS: After cortical mastoidectomies were performed in 10 cadaveric temporal bones, the white dot was identified at the junction of short process of the incus and the incus buttress. Using the white dot for anatomical reference, a 2 mm diamond drill bit was used to open the facial recess without first identifying the facial nerve or chorda tympani nerve. After photographs were taken, the facial and chorda tympani nerves were definitively identified and skeletonized to delineate the confines of the facial recess. Photographs were once again acquired in a consistent manner for comparison. Finally, calibrated anatomic measurements were acquired from the 10 distinct image sets. RESULTS: The facial recess was successfully drilled in 10 temporal bones using the posterior ligament as a surgical landmark without injury to the chorda tympani or facial nerve. The median angle taken from the axis of the short process of the incus to the facial nerve - chorda tympani junction was 139.2° (IQR 136.8-141). At the widest point in the facial recess, median distances anterior and posterior to an imaginary line connecting the white dot to the facial nerve - chorda tympani junction were 1.6 mm (IQR 1.5-1.7) and 1.6 mm (IQR 1.6-1.7; p = 0.57), indicating at this point, the white dot reference reliably bisects the facial recess width. Similarly, at the level of the round window niche, median anterior and posterior distances from an imaginary line connecting the white dot to the facial nerve - chorda tympani junction were 1.1 mm (IQR 1.1-1.3) and 1.3 mm (IQR 1.1-1.7; p = 0.07), respectively, once again demonstrating the white dot reliably bisecting the facial recess. CONCLUSIONS: The white dot, representing the posterior ligament of the incus, is a reliable surgical landmark that aids in safe and efficient drilling of the facial recess without first skeletonizing the facial nerve.


Asunto(s)
Implantación Coclear , Yunque , Nervio de la Cuerda del Tímpano/cirugía , Implantación Coclear/métodos , Nervio Facial/cirugía , Humanos , Yunque/cirugía , Ligamentos/cirugía , Reproducibilidad de los Resultados , Ventana Redonda/cirugía , Hueso Temporal/cirugía
6.
Biophys J ; 120(12): 2521-2531, 2021 06 15.
Artículo en Inglés | MEDLINE | ID: mdl-34023297

RESUMEN

DNA looping plays an important role in cells in both regulating and protecting the genome. Often, studies of looping focus on looping by prokaryotic transcription factors like lac repressor or by structural maintenance of chromosomes proteins such as condensin. Here, however, we are interested in a different looping method whereby condensing agents (charge ≥+3) such as protamine proteins neutralize the DNA, causing it to form loops and toroids. We considered two previously proposed mechanisms for DNA looping by protamine. In the first mechanism, protamine stabilizes spontaneous DNA fluctuations, forming randomly distributed loops along the DNA. In the second mechanism, protamine binds and bends the DNA to form a loop, creating a distribution of loops that is biased by protamine binding. To differentiate between these mechanisms, we imaged both spontaneous and protamine-induced loops on short-length (≤1 µm) DNA fragments using atomic force microscopy. We then compared the spatial distribution of the loops to several model distributions. A random looping model, which describes the mechanism of spontaneous DNA folding, fit the distribution of spontaneous loops, but it did not fit the distribution of protamine-induced loops. Specifically, it failed to predict a peak in the spatial distribution of loops at an intermediate location along the DNA. An electrostatic multibinding model, which was created to mimic the bind-and-bend mechanism of protamine, was a better fit of the distribution of protamine-induced loops. In this model, multiple protamines bind to the DNA electrostatically within a particular region along the DNA to coordinate the formation of a loop. We speculate that these findings will impact our understanding of protamine's in vivo role for looping DNA into toroids and the mechanism of DNA condensation by condensing agents more broadly.


Asunto(s)
ADN , Protaminas , Cromosomas/metabolismo , ADN/genética , Represoras Lac/metabolismo , Conformación de Ácido Nucleico
7.
Am J Physiol Cell Physiol ; 318(3): C476-C485, 2020 03 01.
Artículo en Inglés | MEDLINE | ID: mdl-31875698

RESUMEN

Cell migration is centrally involved in a myriad of physiological processes, including morphogenesis, wound healing, tissue repair, and metastatic growth. The bioenergetics that underlie migratory behavior are not fully understood, in part because of variations in cell culture media and utilization of experimental cell culture systems that do not model physiological connective extracellular fibrous networks. In this study, we evaluated the bioenergetics of C2C12 myoblast migration and force production on fibronectin-coated nanofiber scaffolds of controlled diameter and alignment, fabricated using a nonelectrospinning spinneret-based tunable engineered parameters (STEP) platform. The contribution of various metabolic pathways to cellular migration was determined using inhibitors of cellular respiration, ATP synthesis, glycolysis, or glucose uptake. Despite immediate effects on oxygen consumption, mitochondrial inhibition only modestly reduced cell migration velocity, whereas inhibitors of glycolysis and cellular glucose uptake led to striking decreases in migration. The migratory metabolic sensitivity was modifiable based on the substrates present in cell culture media. Cells cultured in galactose (instead of glucose) showed substantial migratory sensitivity to mitochondrial inhibition. We used nanonet force microscopy to determine the bioenergetic factors responsible for single-cell force production and observed that neither mitochondrial nor glycolytic inhibition altered single-cell force production. These data suggest that myoblast migration is heavily reliant on glycolysis in cells grown in conventional media. These studies have wide-ranging implications for the causes, consequences, and putative therapeutic treatments aimed at cellular migration.


Asunto(s)
Movimiento Celular/fisiología , Metabolismo Energético/fisiología , Nanofibras , Animales , Antracenos/farmacología , Movimiento Celular/efectos de los fármacos , Células Cultivadas , Metabolismo Energético/efectos de los fármacos , Galactosa/farmacología , Glucólisis/efectos de los fármacos , Glucólisis/fisiología , Ratones
8.
Int J Sport Nutr Exerc Metab ; 30(2): 165­173, 2020 03 01.
Artículo en Inglés | MEDLINE | ID: mdl-32023539

RESUMEN

The purpose of this study was to evaluate the impact of fall season vitamin D3 supplementation on strength/power, body composition, and anabolic hormones in swimmers with optimal vitamin D status at summer's end. Male and female National Collegiate Athletic Association Division I swimmers (N = 19) with optimal 25-hydroxyvitamin D [25(OH)D] randomly received 5,000 IU of vitamin D3 (VITD) or placebo (PLA) daily for 12 weeks while participating in swimming and strength and conditioning training (August-November). Before and after the intervention, the participants underwent blood sampling for analysis of serum 25(OH)D, parathyroid hormone, total testosterone, free testosterone, sex hormone-binding globulin, and insulin-like growth factor 1, dual-energy X-ray absorptiometry, and strength/power testing (bench press, squat, dead lift, standing broad jump, vertical jump, and dips and pull-ups). Sex was used as a covariate for analyses. The 25(OH)D was decreased by 44% in PLA (p < .05) and increased by 8% in VITD over the 12 weeks. Fat-free mass increased in VITD (56.4-59.1 kg; p < .05), but not PLA (59.4-59.7 kg; p < .01). Significant Group × Time interaction effects were observed for dead lift (F = 21.577, p < .01) and vertical jump (F = 11.219, p < .01), but no other strength/power tests. Total testosterone decreased similarly in both groups, but free testosterone decreased and sex hormone-binding globulin increased only in PLA (p < .01). There were no group differences or changes in insulin-like growth factor 1 with the intervention. The findings suggest that vitamin D supplementation is an efficacious strategy to maintain 25(OH)D during the fall season training and to enhance some aspects of strength/power and fat-free mass in swimmers. Further research on the relationship between vitamin D and anabolic hormones is needed.

9.
J Immunol ; 198(6): 2260-2268, 2017 03 15.
Artículo en Inglés | MEDLINE | ID: mdl-28159898

RESUMEN

Nucleotide oligomerization domain-like receptor X1 (NLRX1) has been implicated in viral response, cancer progression, and inflammatory disorders; however, its role as a dual modulator of CD4+ T cell function and metabolism has not been defined. The loss of NLRX1 results in increased disease severity, populations of Th1 and Th17 cells, and inflammatory markers (IFN-γ, TNF-α, and IL-17) in mice with dextran sodium sulfate-induced colitis. To further characterize this phenotype, we used in vitro CD4+ T cell-differentiation assays and show that NLRX1-deficient T cells have a greater ability to differentiate into an inflammatory phenotype and possess greater proliferation rates. Further, NLRX1-/- cells have a decreased responsiveness to immune checkpoint pathways and greater rates of lactate dehydrogenase activity. When metabolic effects of the knockout are impaired, NLRX1-deficient cells do not display significant differences in differentiation or proliferation. To confirm the role of NLRX1 specifically in T cells, we used an adoptive-transfer model of colitis. Rag2-/- mice receiving NLRX1-/- naive or effector T cells experienced increased disease activity and effector T cell populations, whereas no differences were observed between groups receiving wild-type or NLRX1-/- regulatory T cells. Metabolic effects of NLRX1 deficiency are observed in a CD4-specific knockout of NLRX1 within a Citrobacter rodentium model of colitis. The aerobic glycolytic preference in NLRX1-/- effector T cells is combined with a decreased sensitivity to immunosuppressive checkpoint pathways to provide greater proliferative capabilities and an inflammatory phenotype bias leading to increased disease severity.


Asunto(s)
Citrobacter rodentium/inmunología , Colitis/inmunología , Infecciones por Enterobacteriaceae/inmunología , Enfermedades Inflamatorias del Intestino/inmunología , Proteínas Mitocondriales/metabolismo , Linfocitos T Reguladores/inmunología , Células TH1/inmunología , Células Th2/inmunología , Traslado Adoptivo , Animales , Proliferación Celular/genética , Células Cultivadas , Colitis/inducido químicamente , Sulfato de Dextran , Modelos Animales de Enfermedad , Humanos , Interferón gamma/metabolismo , Interleucina-17/metabolismo , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Proteínas Mitocondriales/genética , Factor de Necrosis Tumoral alfa/metabolismo
10.
Am J Physiol Regul Integr Comp Physiol ; 315(6): R1096-R1106, 2018 12 01.
Artículo en Inglés | MEDLINE | ID: mdl-30256682

RESUMEN

Heat-stressed pigs experience metabolic alterations, including altered insulin profiles, reduced lipid mobilization, and compromised intestinal integrity. This is bioenergetically distinct from thermal neutral pigs on a similar nutritional plane. To delineate differences in substrate preferences between direct and indirect (via reduced feed intake) heat stress effects, skeletal muscle fuel metabolism was assessed. Pigs (35.3 ± 0.8 kg) were randomly assigned to three treatments: thermal neutral fed ad libitum (TN; 21°C, n = 8), heat stress fed ad libitum (HS; 35°C, n = 8), and TN, pair-fed/HS intake (PF; n = 8) for 7 days. Body temperature (TB) and feed intake (FI) were recorded daily. Longissimus dorsi muscle was biopsied for metabolic assays on days -2, 3, and 7 relative to initiation of environmental treatments. Heat stress increased TB and decreased FI ( P < 0.05). Heat stress inhibited incomplete fatty acid oxidation and glucose oxidation ( P < 0.05). Metabolic flexibility decreased in HS pigs compared with TN and PF controls ( P < 0.05). Both phosphofructokinase and pyruvate dehydrogenase (PDH) activities increased in PF ( P < 0.05); however, TN and HS did not differ. Heat stress inhibited citrate synthase and ß-hydroxyacyl-CoA dehydrogenase (ß-HAD) activities ( P < 0.05). Heat stress did not alter PDH phosphorylation or carnitine palmitoyltransferase 1 abundance but reduced acetyl-CoA carboxylase 1 (ACC1) protein abundance ( P < 0.05). In conclusion, HS decreased skeletal muscle fatty acid oxidation and metabolic flexibility, likely involving ß-HAD and ACC regulation.


Asunto(s)
Temperatura Corporal/fisiología , Trastornos de Estrés por Calor , Respuesta al Choque Térmico/fisiología , Músculo Esquelético/metabolismo , Fenómenos Fisiológicos Nutricionales de los Animales/fisiología , Animales , Suplementos Dietéticos/efectos adversos , Ingestión de Alimentos/fisiología , Estrés Fisiológico/fisiología , Porcinos/crecimiento & desarrollo
11.
Molecules ; 23(9)2018 Sep 13.
Artículo en Inglés | MEDLINE | ID: mdl-30216981

RESUMEN

In diabetes mellitus, the excessive rate of glucose production from the liver is considered a primary contributor for the development of hyperglycemia, in particular, fasting hyperglycemia. In this study, we investigated whether kaempferol, a flavonol present in several medicinal herbs and foods, can be used to ameliorate diabetes in an animal model of insulin deficiency and further explored the mechanism underlying the anti-diabetic effect of this flavonol. We demonstrate that oral administration of kaempferol (50 mg/kg/day) to streptozotocin-induced diabetic mice significantly improved hyperglycemia and reduced the incidence of overt diabetes from 100% to 77.8%. This outcome was accompanied by a reduction in hepatic glucose production and an increase in glucose oxidation in the muscle of the diabetic mice, whereas body weight, calorie intake, body composition, and plasma insulin and glucagon levels were not altered. Consistently, treatment with kaempferol restored hexokinase activity in the liver and skeletal muscle of diabetic mice while suppressed hepatic pyruvate carboxylase activity and gluconeogenesis. These results suggest that kaempferol may exert antidiabetic action via promoting glucose metabolism in skeletal muscle and inhibiting gluconeogenesis in the liver.


Asunto(s)
Diabetes Mellitus Experimental/tratamiento farmacológico , Glucosa/metabolismo , Hipoglucemiantes/administración & dosificación , Quempferoles/administración & dosificación , Hígado/metabolismo , Administración Oral , Animales , Diabetes Mellitus Experimental/metabolismo , Regulación de la Expresión Génica/efectos de los fármacos , Gluconeogénesis/efectos de los fármacos , Hexoquinasa/metabolismo , Hipoglucemiantes/farmacología , Quempferoles/farmacología , Hígado/efectos de los fármacos , Masculino , Ratones , Músculos/efectos de los fármacos , Músculos/metabolismo , Piruvato Carboxilasa/metabolismo , Estreptozocina , Resultado del Tratamiento
12.
Am J Physiol Regul Integr Comp Physiol ; 309(3): R304-13, 2015 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-26084695

RESUMEN

Toll-like receptor-4 (TLR-4) is elevated in skeletal muscle of obese humans, and data from our laboratory have shown that activation of TLR-4 in skeletal muscle via LPS results in decreased fatty acid oxidation (FAO). The purpose of this study was to determine whether overexpression of TLR-4 in skeletal muscle alters mitochondrial function and whole body metabolism in the context of a chow and high-fat diet. C57BL/6J mice (males, 6-8 mo of age) with skeletal muscle-specific overexpression of the TLR-4 (mTLR-4) gene were created and used for this study. Isolated mitochondria and whole muscle homogenates from rodent skeletal muscle (gastrocnemius and quadriceps) were investigated. TLR-4 overexpression resulted in a significant reduction in FAO in muscle homogenates; however, mitochondrial respiration and reactive oxygen species (ROS) production did not appear to be affected on a standard chow diet. To determine the role of TLR-4 overexpression in skeletal muscle in response to high-fat feeding, mTLR-4 mice and WT control mice were fed low- and high-fat diets for 16 wk. The high-fat diet significantly decreased FAO in mTLR-4 mice, which was observed in concert with elevated body weight and fat, greater glucose intolerance, and increase in production of ROS and cellular oxidative damage compared with WT littermates. These findings suggest that TLR-4 plays an important role in the metabolic response in skeletal muscle to high-fat feeding.


Asunto(s)
Dieta Alta en Grasa , Mitocondrias/metabolismo , Músculo Esquelético/metabolismo , Obesidad/metabolismo , Receptor Toll-Like 4/metabolismo , Adaptación Fisiológica , Alimentación Animal , Animales , Composición Corporal/fisiología , Peso Corporal/fisiología , Metabolismo Energético/fisiología , Resistencia a la Insulina/fisiología , Masculino , Ratones Endogámicos C57BL
13.
Exp Cell Res ; 319(10): 1431-42, 2013 Jun 10.
Artículo en Inglés | MEDLINE | ID: mdl-23518387

RESUMEN

Tumor cells often exhibit an altered metabolic phenotype. However, it is unclear as to when this switch takes place in ovarian cancer, and the potential for these changes to serve as therapeutic targets in clinical prevention and intervention trials. We used our recently developed and characterized mouse ovarian surface epithelial (MOSE) cancer progression model to study metabolic changes in distinct disease stages. As ovarian cancer progresses, complete oxidation of glucose and fatty acids were significantly decreased, concurrent with increases in lactate excretion and (3)H-deoxyglucose uptake by the late-stage cancer cells, shifting the cells towards a more glycolytic phenotype. These changes were accompanied by decreases in TCA flux but an increase in citrate synthase activity, providing substrates for de novo fatty acid and cholesterol synthesis. Also, uncoupled maximal respiration rates in mitochondria decreased as cancer progressed. Treatment of the MOSE cells with 1.5 µM sphingosine, a bioactive sphingolipid metabolite, decreased citrate synthase activity, increased TCA flux, decreased cholesterol synthesis and glycolysis. Together, our data confirm metabolic changes during ovarian cancer progression, indicate a stage specificity of these changes, and suggest that multiple events in cellular metabolism are targeted by exogenous sphingosine which may be critical for future prevention trials.


Asunto(s)
Progresión de la Enfermedad , Neoplasias Glandulares y Epiteliales/metabolismo , Neoplasias Ováricas/metabolismo , Esfingosina/farmacología , Animales , Carcinoma Epitelial de Ovario , Línea Celular Tumoral , Respiración de la Célula , Colesterol/metabolismo , Citrato (si)-Sintasa/antagonistas & inhibidores , Citrato (si)-Sintasa/metabolismo , Ciclo del Ácido Cítrico/efectos de los fármacos , Medio de Cultivo Libre de Suero , Activación Enzimática , Ácidos Grasos/metabolismo , Glucosa/metabolismo , Glucólisis/efectos de los fármacos , Ácido Láctico/metabolismo , Ratones , Mitocondrias/metabolismo , Neoplasias Glandulares y Epiteliales/patología , Neoplasias Ováricas/patología , Oxidación-Reducción , Oxígeno/metabolismo
14.
Laryngoscope Investig Otolaryngol ; 9(1): e1203, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38362188

RESUMEN

Objectives: Single-use rhinolaryngoscopes were brought to market in 2019 as an alternative to traditional reusable scopes and have garnered interest across settings given portability and potential cost advantages. While single-use was previously evaluated compared to traditional devices, the overall impact to the consult experience for both users and patients has not been captured. Methods: Eighteen residents performed consults with both single-use and reusable rhinolaryngoscope systems on alternating weeks. A five-question cumulative survey administered across three assessment points over a 12-week period using a five-point rating system to rate favorability. Residents and patients also completed four-point scale surveys following procedure(s) to capture the consult experience. Statistical analyses were performed to measure significance differences between survey responses between the two systems. Results: Single-use rhinolaryngoscopes received higher overall ratings compared with reusables across each metric captured including overall consult time (4.3 vs. 2.2, p < .001), multiscope consults (4.4 vs. 3.1, p < .001), patient communication (4.6 vs. 2.1, p < .001), teaching opportunities (4.6 vs. 2.1, p < .001), and overall ease of use (4.7 vs. 2.6, p < .001). Residents rated single-use higher than reusable after each procedure in terms of ease of use (1.07 vs. 2.68, p < .001) and visual clarity (1.27 vs. 1.89, p = .003), while patients rated single-use higher for understanding of illness (3.9 vs. 3.1, p < .001) and understanding of treatment rationale (3.9 vs. 3.1, p < .001). Conclusion: Resident and patient experience feedback favored single-use rhinolaryngoscopes compared to reusable scope technology across multiple surveyed measurables. Single-use rhinolaryngoscopes provide a viable tool for otorhinolaryngologist and other clinicians to perform rhinolaryngoscopy consults. Level of Evidence: 4.

15.
Front Immunol ; 15: 1359534, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38352866

RESUMEN

Introduction: Leaky gut has been linked to autoimmune disorders including lupus. We previously reported upregulation of anti-flagellin antibodies in the blood of lupus patients and lupus-prone mice, which led to our hypothesis that a leaky gut drives lupus through bacterial flagellin-mediated activation of toll-like receptor 5 (TLR5). Methods: We created MRL/lpr mice with global Tlr5 deletion through CRISPR/Cas9 and investigated lupus-like disease in these mice. Result: Contrary to our hypothesis that the deletion of Tlr5 would attenuate lupus, our results showed exacerbation of lupus with Tlr5 deficiency in female MRL/lpr mice. Remarkably higher levels of proteinuria were observed in Tlr5 -/- MRL/lpr mice suggesting aggravated glomerulonephritis. Histopathological analysis confirmed this result, and Tlr5 deletion significantly increased the deposition of IgG and complement C3 in the glomeruli. In addition, Tlr5 deficiency significantly increased renal infiltration of Th17 and activated cDC1 cells. Splenomegaly and lymphadenopathy were also aggravated in Tlr5-/- MRL/lpr mice suggesting impact on lymphoproliferation. In the spleen, significant decreased frequencies of regulatory lymphocytes and increased germinal centers were observed with Tlr5 deletion. Notably, Tlr5 deficiency did not change host metabolism or the existing leaky gut; however, it significantly reshaped the fecal microbiota. Conclusion: Global deletion of Tlr5 exacerbates lupus-like disease in MRL/lpr mice. Future studies will elucidate the underlying mechanisms by which Tlr5 deficiency modulates host-microbiota interactions to exacerbate lupus.


Asunto(s)
Glomerulonefritis , Receptor Toll-Like 5 , Animales , Femenino , Humanos , Ratones , Glomerulonefritis/patología , Riñón/patología , Ratones Endogámicos MRL lpr , Proteinuria
16.
bioRxiv ; 2024 Feb 05.
Artículo en Inglés | MEDLINE | ID: mdl-38370628

RESUMEN

DNA-PAINT combined with total Internal Reflection Fluorescence (TIRF) microscopy enables the highest localization precisions, down to single nanometers in thin biological samples, due to TIRF's unique method for optical sectioning and attaining high contrast. However, most cellular targets elude the accessible TIRF range close to the cover glass and thus require alternative imaging conditions, affecting resolution and image quality. Here, we address this limitation by applying ultrathin physical cryosectioning in combination with DNA-PAINT. With "tomographic & kinetically-enhanced" DNA-PAINT (tokPAINT), we demonstrate the imaging of nuclear proteins with sub-3 nanometer localization precision, advancing the quantitative study of nuclear organization within fixed cells and mouse tissues at the level of single antibodies. We believe that ultrathin sectioning combined with the versatility and multiplexing capabilities of DNA-PAINT will be a powerful addition to the toolbox of quantitative DNA-based super-resolution microscopy in intracellular structural analyses of proteins, RNA and DNA in situ.

17.
J Neurosurg ; : 1-9, 2024 Mar 22.
Artículo en Inglés | MEDLINE | ID: mdl-38518294

RESUMEN

OBJECTIVE: Olfactory neuroblastoma (ONB) is a rare, malignant tumor of the sinonasal tract that arises from olfactory epithelium. Although surgery is the preferred first-line treatment, tumor involvement of adjacent structures may preclude the ability to achieve negative margins during initial resection. Herein, the authors examine the oncological outcomes of patients with positive margins after primary resection of ONB, with the aim of determining predictors of disease progression and patterns of recurrence. METHODS: The authors performed an institutional review of 25 patients with positive-margin ONB after resection. Cox survival analyses were used to determine any statistically significant predictors of worse progression-free survival (PFS) and overall survival (OS). RESULTS: A total of 93 patients who were diagnosed with ONB were identified, of whom 25 patients had positive margins following their primary resection. Eleven (44%) had a delayed finding of positive margins that were initially negative in the operating room but returned as positive on final pathology. Four patients had subtotal resection (STR), whereas the remaining patients underwent gross-total resection. Twenty-four patients received adjuvant radiotherapy (96%), and 15 additionally received adjuvant chemotherapy (60%). Fourteen patients (56%) experienced recurrence/progression at a median time of 35 months following resection (IQR 19-70 months). Local recurrence occurred in 10 patients (40%), regional in 9 (36%), and distant metastasis in 2 (8%). In Cox survival analyses, the 5-year PFS and OS were 55.1% and 79.2%, respectively. Kadish stage D was predictive of worse PFS in univariate (hazard ratio [HR] 15.67, 95% CI 3.38-72.61, p < 0.001) and multivariate (HR 15.46, 95% CI 1.45-164.91, p = 0.023) analyses. Hyams grade, adjuvant chemotherapy, and primary radiotherapy were not associated with PFS. Furthermore, Kadish stage D and STR were predictive of worse OS in univariate analysis (HR 12.64, 95% CI 2.03-78.86, p = 0.007; HR 7.31, 95% CI 1.45-36.84, p = 0.016; respectively). However, local and regional recurrence was not associated with worse OS. CONCLUSIONS: Approximately half of patients with positive-margin ONB may experience disease recurrence. Patients with an advanced disease stage (Kadish D) may have a higher likelihood of developing recurrence/progression. Furthermore, patients with tumor burden following resection (STR and Kadish D) may have worse OS. However, in positive-margin ONB with no gross disease following initial resection, the presence of disease recurrence does not significantly alter survival when receiving salvage therapy.

18.
JAMA Otolaryngol Head Neck Surg ; 149(9): 837-844, 2023 09 01.
Artículo en Inglés | MEDLINE | ID: mdl-37535372

RESUMEN

Importance: Current olfactory neuroblastoma (ONB) staging systems inadequately delineate locally advanced tumors, do not incorporate tumor grade, and poorly estimate survival and recurrence. Objective: The primary aims of this study were to (1) examine the clinical covariates associated with survival and recurrence of ONB in a modern-era multicenter cohort and (2) incorporate Hyams tumor grade into existing staging systems to assess its ability to estimate survival and recurrence. Design, Setting, and Participants: This retrospective, multicenter, case-control study included patients with ONB who underwent treatment between January 1, 2005, and December 31, 2021, at 9 North American academic medical centers. Intervention: Standard-of-care ONB treatment. Main Outcome and Measures: The main outcomes were overall survival (OS), disease-free survival (DFS), and disease-specific survival (DSS) as C statistics for model prediction. Results: A total of 256 patients with ONB (mean [SD] age, 52.0 [15.6] years; 115 female [44.9%]; 141 male [55.1%]) were included. The 5-year rate for OS was 83.5% (95% CI, 78.3%-89.1%); for DFS, 70.8% (95% CI, 64.3%-78.0%); and for DSS, 94.1% (95% CI, 90.5%-97.8%). On multivariable analysis, age, American Joint Committee on Cancer (AJCC) stage, involvement of bilateral maxillary sinuses, and positive margins were associated with OS. Only AJCC stage was associated with DFS. Only N stage was associated with DSS. When assessing the ability of staging systems to estimate OS, the best-performing model was the novel modification of the Dulguerov system (C statistic, 0.66; 95% CI, 0.59-0.76), and the Kadish system performed most poorly (C statistic, 0.57; 95% CI, 0.50-0.63). Regarding estimation of DFS, the modified Kadish system performed most poorly (C statistic, 0.55; 95% CI, 0.51-0.66), while the novel modification of the AJCC system performed the best (C statistic, 0.70; 95% CI, 0.66-0.80). Regarding estimation of DSS, the modified Kadish system was the best-performing model (C statistic, 0.79; 95% CI, 0.70-0.94), and the unmodified Kadish performed the worst (C statistic, 0.56; 95% CI, 0.51-0.68). The ability for novel ONB staging systems to estimate disease progression across stages was also assessed. In the novel Kadish staging system, patients with stage VI disease were approximately 7 times as likely to experience disease progression as patients with stage I disease (hazard ratio [HR], 6.84; 95% CI, 1.60-29.20). Results were similar for the novel modified Kadish system (HR, 8.99; 95% CI, 1.62-49.85) and the novel Dulguerov system (HR, 6.86; 95% CI, 2.74-17.18). Conclusions and Relevance: The study findings indicate that 5-year OS for ONB is favorable and that incorporation of Hyams grade into traditional ONB staging systems is associated with improved estimation of disease progression.


Asunto(s)
Estesioneuroblastoma Olfatorio , Neoplasias Nasales , Humanos , Masculino , Femenino , Persona de Mediana Edad , Estesioneuroblastoma Olfatorio/terapia , Estesioneuroblastoma Olfatorio/mortalidad , Estesioneuroblastoma Olfatorio/patología , Estudios Retrospectivos , Estudios de Casos y Controles , Neoplasias Nasales/patología , Cavidad Nasal , Análisis de Supervivencia , Estadificación de Neoplasias , Progresión de la Enfermedad
19.
Int Forum Allergy Rhinol ; 13(10): 1876-1888, 2023 10.
Artículo en Inglés | MEDLINE | ID: mdl-36841933

RESUMEN

BACKGROUND: Traditional management of olfactory neuroblastoma (ONB) includes margin-negative resection with removal of cribriform plate, dura, and olfactory bulb, regardless of intracranial disease. This approach may be overtreating certain patients. Our investigation examines risk factors associated with occult intracranial disease to optimize therapeutic outcomes. METHODS: This retrospective, multi-institutional cohort study examined clinical covariates associated with occult intracranial involvement. Patient demographics, staging, Hyam's grade, and pathologic involvement of dura, olfactory bulb/tract, and brain were collected. Diagnostic imaging was reviewed. Positive and negative predictive value (NPV) were estimated along with effect size estimates. Cox hazard regression examined associations with overall survival (OS) and disease-free survival (DFS). RESULTS: A total of 224 subjects with new diagnoses of ONB (2005-2021) were identified. Skull base bone involvement on computed tomography (CT) had the highest NPV for pathologic dura (88.0%), olfactory bulb (88%), and brain involvement (97.3%). Hyam's grade category was significantly associated with dural involvement (φC  = 0.26; 95% confidence interval [CI]: 0.16, 0.42). Subjects without radiologic skull base involvement (n = 66) had pathologic positivity of 12.1%. Within this subgroup, Hyam's grade was clinically significant for dural positivity (φ = 0.34; 95% CI: -0.12, 0.71) with 28.6% involvement in high grade tumors. Neither clinical nor pathologic positivity of intracranial structures were associated with significantly different OS or DFS. CONCLUSIONS: Both CT and magnetic resonance imaging (MRI) had reasonably good NPV for involvement of dura and olfactory bulb. Higher Hyam's grade was associated with dural involvement. Patients with low-grade tumors not involving the skull base may be suitable for avoiding skull base resection; however, further investigation is warranted.


Asunto(s)
Estesioneuroblastoma Olfatorio , Neoplasias Nasales , Humanos , Estudios de Cohortes , Estesioneuroblastoma Olfatorio/diagnóstico por imagen , Cavidad Nasal/patología , Neoplasias Nasales/diagnóstico por imagen , Estudios Retrospectivos
20.
J Lipid Res ; 53(10): 2186-2197, 2012 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-22847176

RESUMEN

Fish oil (FO) is a potent anti-inflammatory and lipid-lowering agent. Because inflammation can modulate lipid metabolism and vice versa, we hypothesized that combining FO with cyclooxygenase inhibitors (COXIBs), well-known anti-inflammatory drugs, can enhance the anti-inflammatory and lipid-lowering effect of FO. LDLR(-/-) mice were fed a high-fat diet supplemented with 6% olive oil or FO for 12 wk in the presence or absence of indomethacin (Indo, 6 mg/l drinking water). FO reduced plasma total cholesterol by 30% but, in combination with Indo, exerted a greater decrease (44%). The reduction of liver cholesterol ester (CE) and triglycerides (TG) by FO (63% and 41%, respectively) was enhanced by Indo (80% in CE and 64% in TG). FO + Indo greatly increased the expression of genes modulating lipid metabolism and reduced the expression of inflammatory genes compared with control. The mRNA and/or protein expression of pregnane X receptor (PXR) and cytochrome P450 isoforms that alter inflammation and/or lipid metabolism are increased to a greater extent in mice that received FO + Indo. Moroever, the nuclear level of PXR is significantly increased in FO + Indo group. Combining FO with COXIBs may exert their beneficial effects on inflammation and lipid metabolism via PXR and cytochrome P450.


Asunto(s)
Antiinflamatorios/farmacología , Dislipidemias/metabolismo , Hígado Graso/metabolismo , Aceites de Pescado/farmacología , Hipolipemiantes/farmacología , Indometacina/farmacología , Receptores de LDL/genética , Animales , Sistema Enzimático del Citocromo P-450/genética , Sistema Enzimático del Citocromo P-450/metabolismo , Dislipidemias/tratamiento farmacológico , Femenino , Hígado/metabolismo , Hígado/patología , Ratones , Receptor X de Pregnano , ARN Mensajero/metabolismo , Receptores de LDL/metabolismo , Receptores de Esteroides/genética , Receptores de Esteroides/metabolismo
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