RESUMO
BACKGROUND: Some cytokines are strongly implicated in the development of squamous cell carcinoma (SCC) such as the Macrophage migration inhibitory factor (MIF). The haplotype -794 (CATT)5-8 /-173G>C in MIF gene polymorphisms has been associated with some types of cancer. The aim of this study is to establish the possible association between the presence of this haplotype in the MIF gene and its subsequent soluble levels with the susceptibility of SCC in western Mexican population. METHODS: This study included 175 SCC patients and 175 age-sex-matched individuals as a reference group (RG) from western Mexico. Genomic DNA was extracted from peripheral blood leukocytes. Polymorphisms were genotyped by endpoint PCR and PCR-RFLP, and the determination of MIF serum levels was measured by ELISA. Clinical characteristics were evaluated by a group of dermatologists. RESULTS: Analysis of [-794(CATT)5-8 /-173G>C] MIF gene polymorphisms showed that the 5C (OR = 2.7, p = 0.02) and the 7G (OR = 3.39, p < 0.01) haplotypes are associated with susceptibility in SCC. MIF soluble levels in SCC patients showed a median of 13.93 ng/mL, whereas the reference group showed 6.000 ng/mL. CONCLUSIONS: Our findings suggest that 5C and 7G [-794(CATT)5-8 /-173G>C] MIF gene haplotypes are associated with susceptibility to SCC and that SCC patients present increased soluble levels of MIF.
Assuntos
Carcinoma de Células Escamosas , Fatores Inibidores da Migração de Macrófagos , Neoplasias Cutâneas , Humanos , Haplótipos , Carcinoma de Células Escamosas/genética , México , Predisposição Genética para Doença , Neoplasias Cutâneas/genética , Polimorfismo Genético , Fatores Inibidores da Migração de Macrófagos/genética , Oxirredutases Intramoleculares/genéticaRESUMO
BACKGOUND: In the workup of follicular lymphoma (FL), bone marrow biopsy (BMB) assessment is a key component of FLIPI and FLIPI2, the most widely used outcome scores. During the previous decade, several studies explored the role of FDG-PET/CT for detecting nodal and extranodal disease, with only one large study comparing both techniques. METHODS: The aim of our study was to evaluate the diagnostic accuracy and the prognostic impact of both procedures in a retrospective cohort of 299 FL patients with both tests performed at diagnosis. In order to avoid a collinearity bias, FLIPI2 was deconstructed in its founding parameters, and the bone marrow involvement (BMI) parameter separately included as: a positive BMB, a positive PET/CT, the combined "PET/CT and BMB positive" or "PET/CT or BMB positive". These variables were also confronted independently with the POD24 in 233 patients treated with intensive regimens. RESULTS: In the total cohort, bone marrow was involved in 124 and 60 patients by BMB and PET/CT, respectively. In terms of overall survival, age > 60 y.o. and the combined "PET/CT or BMB positive" achieved statistical independence as a prognostic factor. In patients treated with an intensive regimen, only the combined "PET/CT or BMB positive" added prognostic value for a shorter overall survival, when confronted with the POD24. CONCLUSION: Our results show that in FL both BMB and PET/CT should be considered at diagnosis, as their combined assessment provides independent prognostic value in the context of the most widely use clinical scores.
Assuntos
Linfoma Folicular , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Humanos , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada/métodos , Fluordesoxiglucose F18 , Linfoma Folicular/diagnóstico por imagem , Linfoma Folicular/patologia , Medula Óssea/diagnóstico por imagem , Medula Óssea/patologia , Prognóstico , Estudos de Coortes , Estudos Retrospectivos , Tomografia por Emissão de Pósitrons/métodos , BiópsiaRESUMO
BACKGROUND: Lymphocytoma cutis (LC) is a benign reactive lymphoproliferative B-cell process. It has two variants: localized type with solitary lesions and miliarial type with numerous lesions. The objective was to investigate the characteristics of LC with emphasis on the miliarial type. METHODS: Retrospective study, patients with clinical and histopathological diagnosis of LC were included. Age, sex, evolution time, affected site, and type of treatment were investigated. In miliarial-type LC, the histological and immunohistochemical characteristics were also investigated. RESULTS: In an 18-year period, there were 102 patients found with LC: 72 (71%) corresponded to females, the median age was 45 years, the median evolution time was 4 months, and the face was the most predominant affected area in 81 (79%) cases. Localized-type LC corresponded to 88 (86%) cases, and miliarial type in 14 (14%). The most common treatment was surgery, which was used in 32 (31%) patients, all of whom had localized type (P < 0.01). The most frequent treatment for miliarial-type LC was corticosteroids in five (36%, P = 0.32), the predominant histopathological pattern was nodular in 10 (71%) specimens, and immunohistochemistry was performed in 11 (79%), where all were positive for CD20 with polyclonality to kappa and lambda light chains. CONCLUSIONS: The importance of LC lies in that it can be clinically and histopathologically confused with cutaneous lymphoma and that it is a rare entity, with its miliarial variant being rarer still. This study provides information on the clinical-histological characteristics of LC and its immunohistochemistry.
Assuntos
Pseudolinfoma , Neoplasias Cutâneas , Diagnóstico Diferencial , Feminino , Humanos , Imuno-Histoquímica , Pessoa de Meia-Idade , Pseudolinfoma/diagnóstico , Estudos RetrospectivosRESUMO
Lanzhousaurus magnidens, a large non-hadrosauriform iguanodontian dinosaur from the Lower Cretaceous Hekou Group of Gansu Province, China has the largest known herbivorous dinosaur teeth. Unlike its hadrosauriform relatives possessing tooth batteries of many small teeth, Lanzhousaurus utilized a small number (14) of very large teeth (~10 cm long) to create a large, continuous surface for mastication. Here we investigate the significance of Lanzhousaurus in the evolutionary history of iguanodontian-hadrosauriform transition by using a combination of stable isotope analysis and CT imagery. We infer that Lanzhousaurus had a rapid rate of tooth enamel elongation or amelogenesis at 0.24 mm/day with dental tissues common to other Iguanodontian dinosaurs. Among ornithopods, high rates of amelogenesis have been previously observed in hadrosaurids, where they have been associated with a sophisticated masticatory apparatus. These data suggest rapid amelogenesis evolved among non-hadrosauriform iguanodontians such as Lanzhousaurus, representing a crucial step that was exapted for the evolution of the hadrosaurian feeding mechanism.
Assuntos
Amelogênese/fisiologia , Esmalte Dentário/metabolismo , Dinossauros/metabolismo , Fósseis , Animais , China , Isótopos/análise , Isótopos/metabolismoRESUMO
We designed and conducted a series of primordial-soup Miller-Urey style experiments with deuterated gases and reagents to compare the spark-discharge products of a "deuterated world" with the standard reaction in the "hydrogenated world". While the deuteration of the system has little effect on the distribution of amino acid products, significant differences are seen in other regions of the product-space. Not only do we observe about 120â new species, we also see significant differences in their distribution if the two hydrogen isotope worlds are compared. Several isotopologue matches can be identified in both, but a large proportion of products have no equivalent in the corresponding isotope world with ca. 43â new species in the D world and ca. 39â new species in the H world. This shows that isotopic exchange (the addition of only one neutron) may lead to significant additional complexity in chemical space under otherwise identical reaction conditions.
RESUMO
A large number of flavoproteins catalyze the oxidation of amines. Because of the importance of these enzymes in metabolism, their mechanisms have previously been studied using deuterium, nitrogen, and solvent isotope effects. While these results have been valuable for computational studies to distinguish among proposed mechanisms, a measure of the change at the reacting carbon has been lacking. We describe here the measurement of a 13C kinetic isotope effect for a representative amine oxidase, polyamine oxidase. The isotope effect was determined by analysis of the isotopic composition of the unlabeled substrate, N, N'-dibenzyl-1,4-diaminopropane, to obtain a pH-independent value of 1.025. The availability of a 13C isotope effect for flavoprotein-catalyzed amine oxidation provides the first measure of the change in bond order at the carbon involved in this carbon-hydrogen bond cleavage and will be of value to understanding the transition state structure for this class of enzymes.
Assuntos
Isótopos de Carbono/química , Flavinas/química , Monoaminoxidase/química , Animais , Escherichia coli/metabolismo , Flavoproteínas/química , Concentração de Íons de Hidrogênio , Cinética , Espectrometria de Massas , Camundongos , Oxirredutases/química , Oxirredutases atuantes sobre Doadores de Grupo CH-NH/química , Poliaminas/química , Temperatura , Poliamina OxidaseRESUMO
We report a method for the preparation of ordered patterns of Pd species on a substrate based on the use of polystyrene-block-poly(ethylene oxide) copolymer (PS-b-PEO) templates and selective inclusion of palladium (Pd) species in the PEO domains. PS-b-PEO samples of different total molecular masses self-assemble in a cylindrical microphase-separated morphology, in which vertically aligned PEO cylinders, with different diameters depending on the molecular mass, are organized in a hexagonal array of different lateral spacings. The cylindrical nanostructure is maintained after the selective inclusion of Pd species (Pd acetate and Pd nanoparticles (NPs) after reduction of Pd ions of the salt) in the PEO cylinders so that the characteristic sizes (diameters and lateral spacings) of the included Pd species are tuned by the characteristic sizes of the block copolymer (BCP) template, which are regulated by molecular mass. Treatment of nanocomposites at elevated temperatures in air removes the polymer matrix and leads to the formation of arrays of palladium oxide (PdO) NPs covering a solid support. The patterns of PdO NPs are characterized by different particle diameters and gap distances, mirroring the patterns and characteristic nanodimensions of the parent BCPs used as templates.
RESUMO
Chitosan and gelatin are biodegradable and biocompatible polymers which may be used in the preparation of 3D scaffolds with applications in biomedicine. Chitosan/gelatin scaffolds crosslinked with glutaraldehyde were prepared by ice segregation induced self-assembly (ISISA); a unidirectional freezing at -196°C followed freeze-drying to produce macroporous materials with a well-patterned structure. This process may be included within the green chemistry by the preparation of the porous structures without using organic solvents, moreover is a versatile, non-difficult and cheap process. The scaffolds prepared by ISISA were characterized by scanning electron microscopy, attenuated total reflectance Fourier transform infrared spectroscopy, thermal gravimetric analysis, differential scanning calorimetry, and their stability was evaluated by degree swelling and degradation tests. The scaffolds present properties as high porosity, high degree swelling and good stability which make them suitable of applications as biomaterials.
Assuntos
Quitosana/química , Gelatina/química , Hidrogéis/síntese química , Alicerces Teciduais/química , Biocatálise , Reagentes de Ligações Cruzadas/química , Congelamento , Química Verde , Hidrogéis/química , Hidrólise , Interações Hidrofóbicas e Hidrofílicas , Muramidase/metabolismo , PorosidadeRESUMO
Many high-yielding reactions for forming peptide bonds have been developed but these are complex, requiring activated amino-acid precursors and heterogeneous supports. Herein we demonstrate the programmable one-pot dehydration-hydration condensation of amino acids forming oligopeptide chains in around 50% yield. A digital recursive reactor system was developed to investigate this process, performing these reactions with control over parameters such as temperature, number of cycles, cycle duration, initial monomer concentration and initial pH. Glycine oligopeptides up to 20 amino acids long were formed with very high monomer-to-oligomer conversion, and the majority of these products comprised three amino acid residues or more. Having established the formation of glycine homo-oligopeptides, we then demonstrated the co-condensation of glycine with eight other amino acids (Ala, Asp, Glu, His, Lys, Pro, Thr and Val), incorporating a range of side-chain functionality.
Assuntos
Técnicas de Química Sintética/métodos , Oligopeptídeos/síntese química , Aminoácidos , Automação , Cromatografia Líquida de Alta Pressão , Cromatografia de Fase Reversa , Espectrometria de Massas , Fenômenos de Química OrgânicaRESUMO
The GB virus C/hepatitis G virus (GBV C/HGV) is a Flaviviridae member that despite its non pathogenicity, has become of great interest given that it could inhibit the replication of the human immunodeficiency virus (HIV). Therefore, a better knowledge of the virus peptides involved in the cellular membrane fusion mechanism has become our aim. The selected peptide, named E2(347-363), corresponds to the GBV-C/HGV E2 protein and has been synthesized in order to study its interaction with in vitro membrane models. Two phospholipids, varying the charge and the unsaturations of the hydrocarbon chain have been chosen: 1,2-dipalmitoyl-sn-glycero-3-phosphocholine (DPPC) and 1,2-dioleoyl-sn-glycero-3-[phospho-rac-(1-glycerol)] (sodium salt) (DOPG). For our porpoise, we have used the Langmuir monolayer technique and Brewster angle microscopy (BAM) to gain deeper insight into the peptide/lipid interactions. The results obtained allow us to argue in favour of considering E2(347-363) a success candidate for developing further experiments in order to determine its potential role in the GBV C/HGV virus/cell membrane fusion process.
Assuntos
1,2-Dipalmitoilfosfatidilcolina/metabolismo , Membranas Artificiais , Fragmentos de Peptídeos/metabolismo , Fosfatidilgliceróis/metabolismo , Proteínas do Envelope Viral/metabolismo , Vírus GB C , Modelos Moleculares , Pressão , Propriedades de Superfície , Proteínas do Envelope Viral/síntese químicaRESUMO
Antipsychotic-induced D2 receptor occupancy values tend to be lower when measured with [(123)I]IBZM SPECT than with [(11)C]Raclopride PET. To clarify this issue, D2 receptor occupancy was measured in the same subjects using both techniques. Twenty patients with schizophrenia on monotherapy with risperidone (n=7; 3-9 mg/d), olanzapine (n=5; 5-20 mg/d) or clozapine (n=8; 150-450 mg/d) at stable doses, and ten healthy volunteers (HV) underwent both a [(123)I]IBZM SPECT and a [(11)C]Raclopride PET examinations in random order on different days within a week. Patients with schizophrenia were scanned at a fixed interval after last dose administration. Quantification of receptor availability was performed using the most conventional methods from the literature: the tissue ratio derived specific uptake ratios (SUR) were used for SPECT, and simplified reference tissue model (SRTM) derived binding potentials (BP(ND)) for PET. Analysis was performed using both occipital cortex and cerebellum as reference regions for both modalities. Striatal D2 receptor occupancy was measured as the percentage reduction of [(123)I]IBZM SUR or [(11)C]Raclopride BP(ND) compared to the population average measured in HV using the same modality. Occupancy values measured by SPECT were lower than those measured with PET, by 12.4% and 13.8% when occipital cortex and cerebellum were used as reference regions. This difference should be taken in consideration when interpreting reported antipsychotic striatal D2 receptor occupancy values from the literature.
Assuntos
Benzamidas/farmacocinética , Corpo Estriado/diagnóstico por imagem , Corpo Estriado/metabolismo , Pirrolidinas/farmacocinética , Racloprida/farmacocinética , Receptores de Dopamina D2/metabolismo , Adulto , Feminino , Humanos , Masculino , Tomografia por Emissão de Pósitrons/métodos , Compostos Radiofarmacêuticos/farmacocinética , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Distribuição TecidualRESUMO
The 3D phase formation was monitored in relaxation experiments of the collapsed Langmuir monolayers of selected partially fluorinated tetracosanes, that is, F6H18, F8H16, and F10H14. To carry out these experiments, the classical method of surface manometry, such as pi-A isotherms registration and the molecular area-time dependencies, under quasi-static monitoring conditions were applied. The evolution of 3D structures at the water/air interface was observed with Brewster angle microscopy (BAM). The obtained data were interpreted according to the nucleation-growth-collision theory model. It occurred that, even though the investigated chemicals are not classical surfactants and do not possess any polar headgroup, their evolution from a 2D monolayer to 3D structures can be successfully modeled with the above-mentioned theory. The influence of the subphase temperature on the nucleation process is also discussed.
RESUMO
RATIONALE: To assess the paroxetine-induced serotonin transporter (SERT) occupancy (SERTocc) using in vivo (123)I-ADAM SPECT. OBJECTIVES: (123)I-ADAM SPECT was used to investigate the SERTocc induced by paroxetine in major depression disorder (MDD) patients, to compare the SERT availability in drug-free MDD patients and healthy volunteers, and to study the relationship between paroxetine plasma concentrations (Cp) and SERTocc. MATERIALS AND METHODS: Measures of SERT availability by means of (123)I-ADAM SPECT were obtained in ten MDD patients before and after 4- to 6-week treatment with paroxetine 20 mg/day. (123)I-ADAM SPECT measures of SERT availability from a group of ten previously studied age-matched healthy volunteers were used for comparison. The relationship between percentages of SERTocc and paroxetine Cp was studied using an E (max) model. RESULTS: Mean SERTocc values were 66.4 +/- 9.5% in midbrain, 63.0 +/- 9.6% in thalamus, and 61.3 +/- 10.9% in striatum. No significant differences in SERTocc were found among these three regions. No significant differences in mean SERT availability were found in any region between drug-free MDD patients (midbrain = 1.14 +/- 0.15; thalamus = 0.85 +/- 0.13; striatum = 0.70 +/- 0.07) and healthy volunteers (midbrain = 1.19 +/- 0.22; thalamus = 0.96 +/- 0.14; striatum = 0.67 +/- 0.15). The E (max) model returned a SERTocc(max) = 70.5% and a Cp(50) = 2.7 ng/ml. CONCLUSIONS: Using (123)I-ADAM SPECT, treatment with paroxetine 20 mg/day leads to more than 60% SERTocc on average in cerebral regions with known high SERT density. Data from this study do not support the existence of SERT availability differences between drug-free MDD patients and healthy volunteers. Finally, the E (max) model is suitable for the study of paroxetine Cp relationship to (123)I-ADAM SPECT-measured SERTocc. This approach may be useful for pharmacokinetic-pharmacodynamic relationships in drug development.
Assuntos
Encéfalo/metabolismo , Transtorno Depressivo/metabolismo , Paroxetina/farmacologia , Proteínas da Membrana Plasmática de Transporte de Serotonina/metabolismo , Adulto , Encéfalo/efeitos dos fármacos , Cinanserina/análogos & derivados , Cinanserina/metabolismo , Corpo Estriado/efeitos dos fármacos , Corpo Estriado/metabolismo , Transtorno Depressivo/tratamento farmacológico , Transtorno Depressivo/patologia , Feminino , Humanos , Radioisótopos do Iodo , Masculino , Mesencéfalo/efeitos dos fármacos , Mesencéfalo/metabolismo , Pessoa de Meia-Idade , Paroxetina/sangue , Paroxetina/uso terapêutico , Ensaio Radioligante/métodos , Antagonistas da Serotonina/farmacologia , Inibidores Seletivos de Recaptação de Serotonina/sangue , Inibidores Seletivos de Recaptação de Serotonina/farmacologia , Inibidores Seletivos de Recaptação de Serotonina/uso terapêutico , Tálamo/efeitos dos fármacos , Tálamo/metabolismo , Tomografia Computadorizada de Emissão de Fóton Único , Resultado do TratamentoRESUMO
Gramicidin A, a polypeptide antibiotic forming transmembrane ion channels, has been incorporated into a Langmuir monolayer formed by a semifluorinated alkane (SFA). In this work, partially fluorinated tetracosane, perfluorohexyloctadecane (F6H18), has been applied, aiming at finding a suitable matrix for gramicidin A to be transferred onto solid support for a biosensor design. For this purpose, the physiological conditions were of special interest (mixed monolayers containing low gramicidin proportion and the surface pressure of 30 mN/m). Mixed monolayers of gramicidin and SFA were found to be miscible within the whole range of mole fractions. A very significant increase of the stability of SFA monolayer has been found in the presence of gramicidin, even at such a low proportion as X(gramicidin) = 0.1, which is reflected in a 3.5-fold increase of the collapse pressure value of mixed monolayer as compared to the film from pure SFA. This interesting phenomenon has been interpreted as being due to the existence of a strong dipole-dipole interaction between both film-forming molecules. Opposite sign of the measured electric surface potential for gramicidin and SFA, resulting from different directions of the dipole moment vectors in both film molecules, implies that the ordered, antiparallel orientation of the dipole moments in the mixed gramicidin/SFA system can be responsible for its extremely high stability.
Assuntos
Antibacterianos/química , Físico-Química/métodos , Gramicidina/química , Tensoativos/química , Alcanos/química , Técnicas Biossensoriais , Química Farmacêutica/métodos , Eletroquímica/métodos , Íons , Modelos Químicos , Pressão , Eletricidade Estática , Propriedades de SuperfícieRESUMO
Se realiza un estudio de 155 niños, procedentes del cuerpo de guardia del Hospital Docente "José Ramón Martínez" de Guanajay, con el diagnóstico de asma bronquial, ingresados en el Servicio de Respiratorio para identificar posibles complicaciones según el juicio clínico del médico. En el 12,9 por ciento de los pacientes se detectó la atelectasia como complicación, las manifestaciones clínicas de ésta quedaron enmascaradas por las de la crisis de asma bronquial. El pulmón derecho resultó ser el más afectado y la forma lobulillar fue la variedad que predominó. Se identificó un sobre diagnóstico de neumopatías inflamatorias, que se confundió con la atelectasia, lo cual trajo como resultado el uso indiscriminado de agentes antimicrobianos(AU)
Assuntos
Criança , Asma/complicações , Atelectasia Pulmonar/etiologia , Serviço Hospitalar de EmergênciaRESUMO
Se realiza un estudio de 155 ninos, procedentes del cuerpo de guardia del Hospital Docente "Jose Ramon Martinez" de Guanajay, con el diagnostico de asma bronquial, ingresados en el Servicio de Respiratorio para identificar posibles complicaciones segun el juicio clinico del medico. En el 12,9 por ciento de los pacientes se detecto la atelectasia como complicacion, las manifestaciones clinicas de esta quedaron enmascaradas por las de la crisis de asma bronquial. El pulmon derecho resulto ser el mas afectado y la forma lobulillar fue la variedad que predomino. Se identifico un sobre diagnostico de neumopatias inflamatorias, que se confundio con la atelectasia, lo cual trajo como resultado el uso indiscriminado de agentes antimicrobianos