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1.
Nucleic Acids Res ; 49(11): 6456-6473, 2021 06 21.
Artículo en Inglés | MEDLINE | ID: mdl-34107032

RESUMEN

RNA-protein interactions are central to all gene expression processes and contribute to a variety of human diseases. Therapeutic approaches targeting RNA-protein interactions have shown promising effects on some diseases that are previously regarded as 'incurable'. Here, we developed a fluorescent on-bead screening platform, RNA Pull-Down COnfocal NAnoscanning (RP-CONA), to identify RNA-protein interaction modulators in eukaryotic cell extracts. Using RP-CONA, we identified small molecules that disrupt the interaction between HuR, an inhibitor of brain-enriched miR-7 biogenesis, and the conserved terminal loop of pri-miR-7-1. Importantly, miR-7's primary target is an mRNA of α-synuclein, which contributes to the aetiology of Parkinson's disease. Our method identified a natural product quercetin as a molecule able to upregulate cellular miR-7 levels and downregulate the expression of α-synuclein. This opens up new therapeutic avenues towards treatment of Parkinson's disease as well as provides a novel methodology to search for modulators of RNA-protein interaction.


Asunto(s)
Proteína 1 Similar a ELAV/antagonistas & inhibidores , MicroARNs/antagonistas & inhibidores , Quercetina/farmacología , alfa-Sinucleína/metabolismo , Evaluación Preclínica de Medicamentos/métodos , Proteína 1 Similar a ELAV/metabolismo , Células HEK293 , Células HeLa , Humanos , MicroARNs/metabolismo , Microscopía Confocal , ARN Mensajero/metabolismo , alfa-Sinucleína/genética
2.
Int J Pediatr Otorhinolaryngol ; 139: 110476, 2020 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-33166754

RESUMEN

Calcinosis cutis describes a condition of pathologic calcium deposition in the dermis. Several subtypes exist, including the subepidermal calcified nodule. The oral mucosal calcified nodule (OMCN) was posited in 1992 as a specific term for a subepidermal calcified nodule occurring in the oral cavity, and since that time only six such lesions have been described in the literature. This report explores a case of OMCN on the palate of a 3-month-old infant with the goal of supplementing extant literature, providing a consideration of the differentials of palatal lesions in the pediatric population, and describing a unique instance in which OMCN resulted in a full-thickness defect requiring palatoplasty for repair.


Asunto(s)
Calcinosis , Neoplasias Cutáneas , Calcinosis/cirugía , Niño , Humanos , Lactante , Mucosa Bucal/cirugía , Hueso Paladar
3.
mSystems ; 4(4)2019 Jun 11.
Artículo en Inglés | MEDLINE | ID: mdl-31186336

RESUMEN

Vanillin (4-hydroxy-3-methoxybenzaldehyde) is an economically important flavor compound that can be made in bacterial cell factories, but toxicity is a major problem for cells producing this aromatic aldehyde. Using (i) a global proteomic analysis supported by multiple physiological experiments, mutant analyses, and inferred transcription factor modeling and (ii) adaptive laboratory evolution (ALE) of vanillin tolerance combined with genome-wide analysis of the underlying mutations, mechanisms of vanillin toxicity in Escherichia coli have been elucidated. We identified 147 proteins that exhibited a significant change in abundance in response to vanillin, giving the first detailed insight into the cellular response to this aldehyde. Vanillin caused accumulation of reactive oxygen species invoking adaptations coordinated by a MarA, OxyR, and SoxS regulatory network and increased RpoS/DksA-dependent gene expression. Differential fumarase C upregulation was found to prevent oxidative damage to FumA and FumB during growth with vanillin. Surprisingly, vanillin-dependent reduction pf copper (II) to copper (I) led to upregulation of the copA gene and growth in the presence of vanillin was shown to be hypersensitive to inhibition by copper ions. AcrD and AaeAB were identified as potential vanillin efflux systems. Vanillin-tolerant strains isolated by ALE had distinct nonsynonymous single nucleotide polymorphisms (SNPs) in gltA that led to increased citrate synthase activity. Strain-specific mutations in cpdA, rob, and marC were also present. One strain had a large (∼10-kb) deletion that included the marRAB region. Our data provide new understanding of bacterial vanillin toxicity and identify novel gene targets for future engineering of vanillin-tolerant strains of E. coli IMPORTANCE A particular problem for the biotechnological production of many of the valuable chemicals that we are now able to manufacture in bacterial cells is that these products often poison the cells producing them. Solutions to improve product yields or alleviate such toxicity using the techniques of modern molecular biology first require a detailed understanding of the mechanisms of product toxicity. Here we have studied the economically important flavor compound vanillin, an aromatic aldehyde that exerts significant toxic effects on bacterial cells. We used high-resolution protein abundance analysis as a starting point to determine which proteins are upregulated and which are downregulated by growth with vanillin, followed by gene expression and mutant studies to understand the mechanism of the response. In a second approach, we evolved bacterial strains with higher vanillin tolerance. Their genome sequences have yielded novel insights into vanillin tolerance that are complementary to the proteomics data set.

4.
Invest Ophthalmol Vis Sci ; 58(12): 5347-5360, 2017 10 01.
Artículo en Inglés | MEDLINE | ID: mdl-29053808

RESUMEN

Purpose: The purpose of this study was to evaluate the impact of supplemental macular carotenoids (including versus not including meso-zeaxanthin) in combination with coantioxidants on visual function in patients with nonadvanced age-related macular degeneration. Methods: In this study, 121 participants were randomly assigned to group 1 (Age-Related Eye Disease Study 2 formulation with a low dose [25 mg] of zinc and an addition of 10 mg meso-zeaxanthin; n = 60) or group 2 (Age-Related Eye Disease Study 2 formulation with a low dose [25 mg] of zinc; n = 61). Visual function was assessed using best-corrected visual acuity, contrast sensitivity (CS), glare disability, retinal straylight, photostress recovery time, reading performance, and the National Eye Institute Visual Function Questionnaire-25. Macular pigment was measured using customized heterochromatic flicker photometry. Results: There was a statistically significant improvement in the primary outcome measure (letter CS at 6 cycles per degree [6 cpd]) over time (P = 0.013), and this observed improvement was statistically comparable between interventions (P = 0.881). Statistically significant improvements in several secondary outcome visual function measures (letter CS at 1.2 and 2.4 cpd; mesopic and photopic CS at all spatial frequencies; mesopic glare disability at 1.5, 3, and 6 cpd; photopic glare disability at 1.5, 3, 6, and 12 cpd; photostress recovery time; retinal straylight; mean and maximum reading speed) were also observed over time (P < 0.05, for all), and were statistically comparable between interventions (P > 0.05, for all). Statistically significant increases in macular pigment at all eccentricities were observed over time (P < 0.0005, for all), and the degree of augmentation was statistically comparable between interventions (P > 0.05). Conclusions: Antioxidant supplementation in patients with nonadvanced age-related macular degeneration results in significant increases in macular pigment and improvements in CS and other measures of visual function. (Clinical trial, http://www.isrctn.com/ISRCTN13894787).


Asunto(s)
Antioxidantes/administración & dosificación , Luteína/uso terapéutico , Degeneración Macular/tratamiento farmacológico , Pigmento Macular/uso terapéutico , Agudeza Visual/fisiología , Anciano , Ácido Ascórbico/administración & dosificación , Sensibilidad de Contraste/fisiología , Método Doble Ciego , Quimioterapia Combinada , Femenino , Deslumbramiento , Humanos , Degeneración Macular/fisiopatología , Masculino , Persona de Mediana Edad , Fotometría/métodos , Lectura , Oligoelementos/administración & dosificación , Vitamina E/administración & dosificación , Zeaxantinas/uso terapéutico , Zinc/administración & dosificación
5.
Br J Nutr ; 117(1): 108-123, 2017 01.
Artículo en Inglés | MEDLINE | ID: mdl-28122649

RESUMEN

The macular carotenoids lutein (L), zeaxanthin (Z) and meso-zeaxanthin (MZ) accumulate at the macula, where they are collectively referred to as macular pigment (MP). Augmentation of this pigment, typically achieved through diet and supplementation, enhances visual function and protects against progression of age-related macular degeneration. However, it is known that eggs are a rich dietary source of L and Z, in a highly bioavailable matrix. In this single-blind placebo-controlled study, L- and MZ-enriched eggs and control non-enriched eggs were fed to human subjects (mean age 41 and 35 years, respectively) over an 8-week period, and outcome measures included MP, visual function and serum concentrations of carotenoids and cholesterol. Serum carotenoid concentrations increased significantly in control and enriched egg groups, but to a significantly greater extent in the enriched egg group (P<0·001 for L, Z and MZ). There was no significant increase in MP in either study group post intervention, and we saw no significant improvement in visual performance in either group. Total cholesterol increased significantly in each group, but it did not exceed the upper limit of the normative range (6·5 mmol/l). Therefore, carotenoid-enriched eggs may represent an effective dietary source of L, Z and MZ, reflected in significantly raised serum concentrations of these carotenoids, and consequentially improved bioavailability for capture by target tissues. However, benefits in terms of MP augmentation and /or improved visual performance were not realised over the 8-week study period, and a study of greater duration will be required to address these questions.


Asunto(s)
Dieta , Huevos/análisis , Mácula Lútea/efectos de los fármacos , Xantófilas/farmacología , Adulto , Femenino , Análisis de los Alimentos , Humanos , Masculino , Persona de Mediana Edad , Fenómenos Fisiológicos de la Nutrición , Visión Ocular/efectos de los fármacos , Xantófilas/administración & dosificación , Xantófilas/química
6.
Invest Ophthalmol Vis Sci ; 57(7): 3429-39, 2016 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-27367585

RESUMEN

PURPOSE: The high-performance visual function associated with central vision is mediated by the macula (the central retina), which accumulates three diet-derived pigments (the carotenoids lutein [L], zeaxanthin [Z], and meso-zeaxanthin [MZ]). Our study sought to investigate the impact on visual function, including contrast sensitivity (CS), of supplementation with these naturally occurring carotenoids, in individuals with low retinal concentrations. METHODS: Subjects consumed daily a formulation containing 10 mg L, 2 mg Z, and 10 mg MZ (active group; n = 53) or placebo (n = 52) for a period of 12 months. Study visits were at baseline, 3, 6, and 12 months. Contrast sensitivity at 6 cycles per degree (cpd) was the primary outcome measure (POM). Secondary outcome measures included CS at other spatial frequencies, best-corrected visual acuity (BCVA), glare disability, photostress recovery, and light scatter. Macular pigment optical density (MPOD) was measured using dual-wavelength autofluorescence, and serum carotenoid concentrations were analyzed using high performance liquid chromatography (HPLC). RESULTS: Compared to placebo, statistically significant improvements from baseline CS were detected at 6 (P = 0.002) and 1.2 (P = 0.004) cpd in the active group. Additionally, improvements in CS were commensurate with the observed increases in retinal concentrations of these carotenoids (r = 0.342, P = 0.002 at 6 cpd). CONCLUSIONS: These results indicate that dietary fortification with the macular carotenoids can have meaningful effects on visual function.


Asunto(s)
Sensibilidad de Contraste/efectos de los fármacos , Suplementos Dietéticos , Luteína/farmacología , Pigmento Macular/fisiología , Zeaxantinas/farmacología , Adulto , Análisis de Varianza , Femenino , Humanos , Luteína/administración & dosificación , Luteína/sangre , Mácula Lútea/fisiopatología , Pigmento Macular/metabolismo , Masculino , Persona de Mediana Edad , Recuperación de la Función/efectos de los fármacos , Estrés Psicológico , Agudeza Visual/efectos de los fármacos , Zeaxantinas/administración & dosificación , Zeaxantinas/sangre
7.
J Pediatr Gastroenterol Nutr ; 58(3): 387-90, 2014 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-24553473

RESUMEN

OBJECTIVE: Chronic blood transfusion therapy reduces clinical events in children with sickle cell anemia but increases risk for an iron-related liver injury. Liver biopsy is the gold standard technique for quantifying liver iron content (LIC) and evaluating liver pathology. Ferritin, liver enzymes, and R2* magnetic resonance imaging of the liver are obtained as surrogate markers. In this study we compared surrogate markers with the gold standard, liver biopsy, in assessing liver histology. METHODS: We conducted a retrospective review of 259 liver biopsies in 109 children with sickle cell anemia on chronic transfusion therapy and chelation therapy during a 9-year period at a single center. Liver pathology was compared with LIC, ferritin, and alanine aminotransferase. RESULTS: Ferritin correlates with LIC (r = 0.74, P < 0.001), although there is a broad range of ferritin values for a given LIC. Furthermore, patients with a high LIC (≥7 mg Fe/g dry weight) demonstrated significantly higher ferritin as compared to the patients with lower LIC <7 (P < 0.001). Periportal/portal inflammation also showed a significant relation. There was no significance when comparing ferritin and lobular inflammation or ferritin and alanine aminotransferase. When evaluating LIC in relation to fibrosis, the present study revealed that there was only a significant correlation with severe fibrosis (F = 36, P < 0.001). CONCLUSIONS: The results suggest that although correlations exist among ferritin and LIC and severe fibrosis and LIC, caution should be taken when they are used in isolation. Liver biopsy provides important pathologic information that cannot be obtained through surrogate markers.


Asunto(s)
Anemia de Células Falciformes/terapia , Ferritinas/metabolismo , Hierro/metabolismo , Cirrosis Hepática/etiología , Hígado/patología , Reacción a la Transfusión , Adolescente , Adulto , Alanina Transaminasa/sangre , Anemia de Células Falciformes/sangre , Anemia de Células Falciformes/metabolismo , Anemia de Células Falciformes/patología , Biomarcadores/sangre , Biomarcadores/metabolismo , Biopsia , Terapia por Quelación , Niño , Preescolar , Humanos , Inflamación/metabolismo , Hígado/metabolismo , Cirrosis Hepática/sangre , Cirrosis Hepática/metabolismo , Estudios Retrospectivos , Índice de Severidad de la Enfermedad , Adulto Joven
8.
Food Chem ; 135(2): 787-98, 2012 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-22868160

RESUMEN

Smoke taint in wines from bushfire smoke exposure has become a concern for wine producers. Smoke taint compounds are primarily derived from pyrolysis of the lignin component of fuels. This work examined the influence of the lignin composition of pyrolysed vegetation on the types of putative smoke taint compounds that accrue in wines. At veraison, Merlot vines were exposed to smoke generated from five vegetation types with differing lignin composition. Smoke was generated under pyrolysis conditions that simulated bushfire temperature profiles. Lignin and smoke composition of each fuel type along with putative smoke taint compounds in wines were determined. The results showed that, regardless of fuel type, the commonly reported guaiacyl lignin derived smoke taint compounds, guaiacol and 4-methylguaiacol, represented about 20% of the total phenols in wines. Quantitatively, syringyl lignin derived compounds dominated the total phenol pools in both free and bound forms. The contributions of p-hydroxyphenyls were generally similar to the guaiacyl sources. A further unexpected outcome of the study was that pine smoke affected wines had significantly elevated levels of syringols compared to the controls although pine fuel and its smoke emission lacked syringyl products.


Asunto(s)
Lignina/química , Preparaciones de Plantas/química , Humo/análisis , Vitis/química , Vino/análisis , Fenoles/química
9.
Mol Microbiol ; 74(3): 742-57, 2009 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-19818021

RESUMEN

The food-borne pathogen Campylobacter jejuni possesses no known tungstoenzymes, yet encodes two ABC transporters (Cj0300-0303 and Cj1538-1540) homologous to bacterial molybdate (ModABC) uptake systems and the tungstate transporter (TupABC) of Eubacterium acidaminophilum respectively. The actual substrates and physiological role of these transporters were investigated. Tryptophan fluorescence spectroscopy and isothermal titration calorimetry of the purified periplasmic binding proteins of each system revealed that while Cj0303 is unable to discriminate between molybdate and tungstate (K(D) values for both ligands of 4-8 nM), Cj1540 binds tungstate with a K(D) of 1.0 +/- 0.2 pM; 50 000-fold more tightly than molybdate. Induction-coupled plasma mass spectroscopy of single and double mutants showed that this large difference in affinity is reflected in a lower cellular tungsten content in a cj1540 (tupA) mutant compared with a cj0303c (modA) mutant. Surprisingly, formate dehydrogenase (FDH) activity was decreased approximately 50% in the tupA strain, and supplementation of the growth medium with tungstate significantly increased FDH activity in the wild type, while inhibiting known molybdoenzymes. Our data suggest that C. jejuni possesses a specific, ultra-high affinity tungstate transporter that supplies tungsten for incorporation into FDH. Furthermore, possession of two MoeA paralogues may explain the formation of both molybdopterin and tungstopterin in this bacterium.


Asunto(s)
Transportadoras de Casetes de Unión a ATP/metabolismo , Proteínas Bacterianas/metabolismo , Campylobacter jejuni/metabolismo , Formiato Deshidrogenasas/metabolismo , Tungsteno/metabolismo , Tungsteno/farmacología , Transportadoras de Casetes de Unión a ATP/genética , Secuencia de Aminoácidos , Antígenos Bacterianos/metabolismo , Proteínas Bacterianas/genética , Transporte Biológico , Campylobacter jejuni/efectos de los fármacos , Campylobacter jejuni/enzimología , Clonación Molecular , Escherichia coli/metabolismo , Proteínas de Escherichia coli/metabolismo , Eubacterium/metabolismo , Formiatos/metabolismo , Molibdeno/metabolismo , Proteínas de Unión Periplasmáticas/genética , Proteínas de Unión Periplasmáticas/metabolismo , ARN Bacteriano/metabolismo , Especificidad por Sustrato , Compuestos de Tungsteno/metabolismo
10.
Mol Microbiol ; 69(1): 77-93, 2008 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-18433445

RESUMEN

Amino acids are key carbon and energy sources for the asaccharolytic food-borne human pathogen Campylobacter jejuni. During microaerobic growth in amino acid rich complex media, aspartate, glutamate, proline and serine are the only amino acids significantly utilized by strain NCTC 11168. The catabolism of aspartate and glutamate was investigated. An aspartase (aspA) mutant (unable to utilize any amino acid except serine) and a Cj0762c (aspB) mutant lacking aspartate:glutamate aminotransferase (unable to utilize glutamate), were severely growth impaired in complex media, and an aspA sdaA mutant (also lacking serine dehydratase) failed to grow in complex media unless supplemented with pyruvate and fumarate. Aspartase was shown by activity and proteomic analyses to be upregulated by oxygen limitation, and aspartate enhanced oxygen-limited growth of C. jejuni in an aspA-dependent manner. Stoichiometric aspartate uptake and succinate excretion involving the redundant DcuA and DcuB transporters indicated that in addition to a catabolic role, AspA can provide fumarate for respiration. Significantly, an aspA mutant of C. jejuni 81-176 was impaired in its ability to persist in the intestines of outbred chickens relative to the parent strain. Together, our data highlight the dual function of aspartase in C. jejuni and suggest a role during growth in the avian gut.


Asunto(s)
Aminoácidos/metabolismo , Aspartato Aminotransferasas/metabolismo , Aspartato Amoníaco-Liasa/metabolismo , Proteínas Bacterianas/metabolismo , Campylobacter jejuni/enzimología , Campylobacter jejuni/crecimiento & desarrollo , Oxígeno/metabolismo , Aerobiosis , Animales , Aspartato Aminotransferasas/genética , Aspartato Amoníaco-Liasa/química , Aspartato Amoníaco-Liasa/genética , Ácido Aspártico/metabolismo , Proteínas Bacterianas/genética , Vías Biosintéticas , Infecciones por Campylobacter/microbiología , Infecciones por Campylobacter/veterinaria , Campylobacter jejuni/química , Campylobacter jejuni/genética , Pollos , Medios de Cultivo/química , Transportadores de Ácidos Dicarboxílicos/genética , Transportadores de Ácidos Dicarboxílicos/metabolismo , Fumaratos/metabolismo , Ácido Glutámico/metabolismo , Humanos , Cinética , Mutación , Transcripción Genética
11.
Neurosurgery ; 59(5): 1109-20; discussion 1120-1, 2006 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-17143245

RESUMEN

OBJECTIVE: Although the chemotherapy drug hydroxyurea (HU) and the antiprogesterone mifepristone (RU486) have been used to treat meningiomas for which surgical and radiation therapies have failed, results have been disappointing. The addition of calcium channel antagonists (CCAs) to chemotherapeutic drugs enhances tumor growth inhibition in other tumor types, and the authors demonstrated that CCAs can block meningioma growth in vitro and in vivo. The purpose of this study was to test the effects of the addition of a CCA to HU or RU486 on meningioma growth. METHODS: Primary and malignant (IOMM-Lee) meningioma cell lines were treated with HU, RU486, or either of these plus diltiazem or verapamil. Assays for cell growth, apoptosis, and fluorescent-activated cell sorting were performed on in vitro cultures. Similar cell lines were implanted into nude mice and were treated with HU or RU486, in combination with a CCA. Tumors were analyzed by light microscopy, MIB-1, and factor VIII immunohistochemical staining studies. RESULTS: The addition of diltiazem or verapamil to HU or RU486 augmented meningioma growth inhibition by 20 to 60% in vitro. In vivo, tumors treated with combination drugs were smaller; and immunohistochemical analysis of the IOMM-Lee tumors showed a 10% decrease in the MIB-1 ratio (from 0.41 to 0.30) and an approximate 75% decrease in microvascular density. CONCLUSION: The addition of diltiazem or verapamil to HU or RU486 augments meningioma growth inhibition in vitro by inducing apoptosis and G1 cell-cycle arrest. The combination of HU and diltiazem inhibited the growth of meningiomas in vivo by decreasing proliferation and microvascular density. These results suggest a possible role for these drugs as an additional adjuvant therapy for recurrent or unresectable meningiomas.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/administración & dosificación , Apoptosis/efectos de los fármacos , Neoplasias Meníngeas/tratamiento farmacológico , Neoplasias Meníngeas/fisiopatología , Meningioma/tratamiento farmacológico , Meningioma/fisiopatología , Anciano , Animales , Antineoplásicos/administración & dosificación , Bloqueadores de los Canales de Calcio/administración & dosificación , Proliferación Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Femenino , Humanos , Hidroxiurea/administración & dosificación , Masculino , Neoplasias Meníngeas/patología , Meningioma/patología , Ratones , Ratones Desnudos , Persona de Mediana Edad , Mifepristona/administración & dosificación , Células Tumorales Cultivadas
12.
Curr Opin Clin Nutr Metab Care ; 6(2): 217-22, 2003 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-12589192

RESUMEN

PURPOSE OF REVIEW: This review will attempt to summarize recent clinical and experimental data on glutamine's use in critical illness. It will try to present the concept of glutamine as a 'drug' or 'nutraceutical', given in addition to standard nutritional support. RECENT FINDINGS: Glutamine, traditionally considered to be a nonessential amino acid, is now considered as 'conditionally essential' following critical illness and injury. States of critical illness lead to significant decreases in plasma levels of glutamine and when this decrease is severe it has been correlated with increased mortality. Laboratory data have demonstrated numerous benefits of glutamine in experimental models of critical illness, including attenuated proinflammatory cytokine expression, improved gut barrier function, enhanced ability to mount a stress response, improved immune cell function, and decreased mortality. Over the last 10 years clinical trials of glutamine supplementation in critical illness have shown benefit with regard to mortality, length of stay, and infectious morbidity. However, data demonstrating a lack of benefit with glutamine supplementation in the critically ill have been presented as well. It appears that dose and route of administration clearly influence the benefit observed from glutamine administration, with high-dose, parenteral glutamine demonstrating an advantage over low-dose, enteral glutamine. SUMMARY: High-dose or parenteral (>0.20-0.30 g/kg/day or > or =30 g/day) glutamine appears to demonstrate the greatest potential for benefit in critically ill patients. No evidence of harm has been observed in studies conducted to date, thus further clinical trials utilizing glutamine as a pharmacologic supplement to standard nutrition are warranted.


Asunto(s)
Enfermedad Crítica/terapia , Glutamina/sangre , Glutamina/uso terapéutico , Cuidados Críticos/métodos , Enfermedad Crítica/mortalidad , Relación Dosis-Respuesta a Droga , Mortalidad Hospitalaria , Humanos , Tiempo de Internación , Apoyo Nutricional
13.
Pediatr Neurosurg ; 36(6): 314-9, 2002 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-12077476

RESUMEN

OBJECTIVE: To determine a solution capable of discerning adipose versus nervous tissue, to aid in surgical separation of the adipose tissue which appears to be visually indistinguishable from nervous tissue in lipomyelomeningoceles (LMMs). METHODS: The following solutes (in normal saline) were investigated, both at 25 and 37 degrees C: beta-carotene, vitamin D, vitamin E, lecithin, hydrogen peroxide, lipase, protease, hyaluronidase, partially purified collagenase, purified collagenase, trypsin, trypsin plus purified collagenase and non-solute-containing saline (control). Each solution was applied to a pediatric lipoma to determine gross effects over a period of approximately 30 min. If a solution appeared to affect the adipose tissue grossly, studies of functional in vivo sensory evoked and spontaneous potentials using that particular solution were conducted upon sheep spinal cord, nerve roots, dura and peripheral nerve. Additionally, histological studies were conducted to determine the effect of that solution upon adipose tissue, spinal cord, myelin, dura and nerve roots. RESULTS: Of all solutions investigated, partially purified collagenase type 1 (T1C; Lot M0M4322, Code CLS-1, Worthington Biochemical Corporation, Lakewood, N.J., USA) at 37 degrees C was the most successful in grossly altering the consistency and appearance of adipose tissue. This change was more apparent over 20-30 min following application of the solution to the adipose tissue. Solutions not containing T1C did not show appreciable results; purified collagenase plus trypsin did not appear comparable or superior to T1C. No significant histological or functional change was noted when comparing the spinal cord, nerve rootlets, myelin, dura or peripheral nerve from the T1C-treated group versus normal (untreated) control groups. CONCLUSION: T1C appears to be a potentially effective solution for application during LMM surgery in the acute setting, and such use of an adjunct solution may significantly aid in the safe surgical resection of LMMs. Pending further research, this technique may be applied for other indications which require discernment or alteration of adipose versus nervous tissue.


Asunto(s)
Tejido Adiposo/efectos de los fármacos , Tejido Adiposo/patología , Lipoma/patología , Lipoma/cirugía , Meningomielocele/patología , Meningomielocele/cirugía , Tejido Nervioso/efectos de los fármacos , Tejido Nervioso/patología , Soluciones Farmacéuticas/química , Soluciones Farmacéuticas/farmacología , Tejido Adiposo/cirugía , Quimioterapia Adyuvante , Niño , Colagenasas/química , Colagenasas/farmacología , Colagenasas/uso terapéutico , Humanos , Técnicas In Vitro , Lipoma/tratamiento farmacológico , Meningomielocele/tratamiento farmacológico , Tejido Nervioso/cirugía , Soluciones Farmacéuticas/uso terapéutico , Factores de Tiempo
14.
Ann Surg ; 235(5): 621-9; discussion 629-30, 2002 May.
Artículo en Inglés | MEDLINE | ID: mdl-11981207

RESUMEN

OBJECTIVE: To evaluate whether gastrin-releasing peptide (GRP) and GRP receptor (GRP-R) expression correlate with tumor behavior and to examine the mitogenic actions of GRP on neuroblastomas. SUMMARY BACKGROUND DATA: Neuroblastoma is the most common solid tumor of infants and children. Despite recent advances in multimodality treatment regimens, the survival for advanced-stage tumors remains dismal. Neuroblastomas are known to produce GRP; however, the proliferative effects of GRP on neuroblastomas have not been elucidated. METHODS: Sections of paraffin-embedded neuroblastomas from 33 patients were analyzed for GRP and GRP-R protein expression by immunohistochemistry. Functional binding of GRP-R to the Ca2+ signaling pathway was examined. In addition, the proliferative effect of GRP on neuroblastoma cells (SK-N-SH, IMR-32, SH-SY5Y, LAN-1) was determined. RESULTS: Immunohistochemical analysis showed GRP and GRP-R protein expression in neuroblastomas; an increased expression of GRP-R was noted in a higher percentage of undifferentiated tumors compared with tumors that were benign. GRP-R mRNA was confirmed in neuroblastoma cell lines. GRP treatment resulted in intracellular calcium [Ca2+]i mobilization in two cell lines (SK-N-SH, LAN-1). GRP treatment stimulated growth of all four neuroblastoma cell lines; this effect was inhibited in SK-N-SH cells by pretreatment with GRP antibody. CONCLUSIONS: These findings show increased GRP-R expression in the more aggressive and undifferentiated neuroblastomas. The synchronous expression of GRP and its receptor, GRP-R, suggests a role for these proteins in tumor growth. Moreover, these findings show enhanced proliferation of neuroblastoma cells in vitro after GRP treatment, suggesting that GRP may act as an autocrine and/or paracrine growth factor for neuroblastomas. Treatment with specific GRP-R antagonists may provide novel adjuvant therapy for neuroblastomas in children.


Asunto(s)
Péptido Liberador de Gastrina/fisiología , Sustancias de Crecimiento/fisiología , Neuroblastoma/metabolismo , Receptores de Bombesina/fisiología , Calcio/metabolismo , División Celular , Línea Celular , Preescolar , Péptido Liberador de Gastrina/metabolismo , Humanos , Inmunohistoquímica , Lactante , ARN Mensajero/biosíntesis , Receptores de Bombesina/metabolismo , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Células Tumorales Cultivadas
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