Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 107
Filtrar
Más filtros

Intervalo de año de publicación
1.
J Chem Phys ; 142(10): 104304, 2015 Mar 14.
Artículo en Inglés | MEDLINE | ID: mdl-25770537

RESUMEN

We report theoretical and experimental total cross sections for electron scattering by phenol (C6H5OH). The experimental data were obtained with an apparatus based in Madrid and the calculated cross sections with two different methodologies, the independent atom method with screening corrected additivity rule (IAM-SCAR), and the Schwinger multichannel method with pseudopotentials (SMCPP). The SMCPP method in the Nopen-channel coupling scheme, at the static-exchange-plus-polarization approximation, is employed to calculate the scattering amplitudes at impact energies ranging from 5.0 eV to 50 eV. We discuss the multichannel coupling effects in the calculated cross sections, in particular how the number of excited states included in the open-channel space impacts upon the convergence of the elastic cross sections at higher collision energies. The IAM-SCAR approach was also used to obtain the elastic differential cross sections (DCSs) and for correcting the experimental total cross sections for the so-called forward angle scattering effect. We found a very good agreement between our SMCPP theoretical differential, integral, and momentum transfer cross sections and experimental data for benzene (a molecule differing from phenol by replacing a hydrogen atom in benzene with a hydroxyl group). Although some discrepancies were found for lower energies, the agreement between the SMCPP data and the DCSs obtained with the IAM-SCAR method improves, as expected, as the impact energy increases. We also have a good agreement among the present SMCPP calculated total cross section (which includes elastic, 32 inelastic electronic excitation processes and ionization contributions, the latter estimated with the binary-encounter-Bethe model), the IAM-SCAR total cross section, and the experimental data when the latter is corrected for the forward angle scattering effect [Fuss et al., Phys. Rev. A 88, 042702 (2013)].

2.
J Chem Phys ; 141(5): 051105, 2014 Aug 07.
Artículo en Inglés | MEDLINE | ID: mdl-25106562

RESUMEN

We report on the shape resonance spectra of phenol-water clusters, as obtained from elastic electron scattering calculations. Our results, along with virtual orbital analysis, indicate that the well-known indirect mechanism for hydrogen elimination in the gas phase is significantly impacted on by microsolvation, due to the competition between vibronic couplings on the solute and solvent molecules. This fact suggests how relevant the solvation effects could be for the electron-driven damage of biomolecules and the biomass delignification [E. M. de Oliveira et al., Phys. Rev. A 86, 020701(R) (2012)]. We also discuss microsolvation signatures in the differential cross sections that could help to identify the solvated complexes and access the composition of gaseous admixtures of these species.


Asunto(s)
Gases/química , Hidrógeno/química , Modelos Químicos , Modelos Moleculares , Fenol/química , Solventes/química , Agua/química , Aniones/química , Sitios de Unión , Simulación por Computador , Enlace de Hidrógeno
3.
J Low Genit Tract Dis ; 18(2): E50-4, 2014 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-24270195

RESUMEN

OBJECTIVE: This report describes a case that illustrates the limitations of the vaccination screening process for human papillomavirus (HPV) infection. CASE: We report an unexpected microinvasive adenocarcinoma of the cervix arising in a young woman vaccinated against HPV as part of a clinical trial 6 years previously and followed up annually by cytology. In January 2012, at age 23 years, the patient received a cytological result of atypical squamous cells, cannot exclude high-grade cervical squamous intraepithelial lesion, and colposcopy showed slight abnormalities. Biopsy revealed an adenocarcinoma in situ. Conization of the cervix was performed, and the diagnosis was microinvasive adenocarcinoma. Polymerase chain reaction and immunohistochemical study of conization material showed positivity for HPV-18 L1, p16, and Ki-67. Retrospective analysis of the clinical trial information revealed that 7 HPV tests had been performed, and all were positive for HPV-18, including the sample collected before the first vaccination. CONCLUSIONS: HPV-18 was present in the cervix before vaccination. Persistent detection of HPV-18 should be considered an important factor in treatment planning. This case demonstrates the need to vaccinate women before their first sexual contact and highlights the need for keeping adequate screening even in vaccinated individuals.


Asunto(s)
Adenocarcinoma/diagnóstico , Adenocarcinoma/virología , Papillomavirus Humano 18/aislamiento & purificación , Vacunas contra Papillomavirus/administración & dosificación , Vacunas contra Papillomavirus/inmunología , Neoplasias del Cuello Uterino/diagnóstico , Neoplasias del Cuello Uterino/virología , Adolescente , Adulto , Biopsia , Femenino , Histocitoquímica , Humanos , Inmunohistoquímica
4.
J Conserv Dent Endod ; 27(3): 274-279, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38634029

RESUMEN

Aims: This study evaluated the effectiveness of different mechanical protocols using rotary brush (RB), ultrasonic tip, and oscillatory system (OS) associated with 2.5% sodium hypochlorite (NaOCl) in the removal of residues and dentin permeability in the cervical and apical segments of the post space. Settings and Design: Experimental in vitro study. Methods: Forty roots from human first molars were prepared and divided into four groups according to the cleaning protocols: Control (CO), NaOCl 2.5% conventional irrigation with a syringe; RB associated with NaOCl 2.5%; ultrasonic tip (US) associated with NaOCl 2.5%; OS associated with NaOCl 2.5%. Statistical Analysis Used: The persistence of residues was evaluated by scanning electron microscopy and data submitted to Kruskal-Wallis and Dunn tests, and dentin permeability evaluated by confocal microscopy and date submitted to ANOVA one-way and Tukey's tests (P = 0.05). Results: There were no differences in residue cleaning among the CO, RB, US, and OS groups, regardless of the analyzed root segment (P > 0.05). When comparing groups, dentin permeability in the CO group was significantly lower in the cervical segment (P < 0.05). Conclusions: The OS group promoted the highest permeability value in the apical segment. RB, US, and OS are similar in removing residues from the post space. However, OS results in higher dentin permeability in the apical segment.

5.
Phys Chem Chem Phys ; 15(5): 1682-9, 2013 Feb 07.
Artículo en Inglés | MEDLINE | ID: mdl-23247550

RESUMEN

We report elastic integral, differential and momentum transfer cross sections for low-energy electron scattering by the cellulose components ß-D-glucose and cellobiose (ß(1 → 4) linked glucose dimer), and the hemicellulose component ß-D-xylose. For comparison with the ß forms, we also obtain results for the amylose subunits α-D-glucose and maltose (α(1 → 4) linked glucose dimer). The integral cross sections show double peaked broad structures between 8 eV and 20 eV similar to previously reported results for tetrahydrofuran and 2-deoxyribose, suggesting a general feature of molecules containing furanose and pyranose rings. These broad structures would reflect OH, CO and/or CC σ* resonances, where inspection of low-lying virtual orbitals suggests significant contribution from anion states. Though we do not examine dissociation pathways, these anion states could play a role in dissociative electron attachment mechanisms, in case they were coupled to the long-lived π* anions found in lignin subunits [de Oliveira et al., Phys. Rev. A, 2012, 86, 020701(R)]. Altogether, the resonance spectra of lignin, cellulose and hemicellulose components establish a physical-chemical basis for electron-induced biomass pretreatment that could be applied to biofuel production.


Asunto(s)
Celulosa/química , Polisacáridos/química , Biomasa , Desoxirribosa/química , Electrones , Furanos/química , Modelos Químicos
6.
Polymers (Basel) ; 15(1)2023 Jan 03.
Artículo en Inglés | MEDLINE | ID: mdl-36616585

RESUMEN

Recent formulations of resin-based composites have incorporated different combinations of materials. However, the mechanical and bonding behavior of these materials with intraradicular posts are unclear. This study aimed to evaluate the effect of light-cure and dual-cure resin composite posts on the fracture resistance of endodontically-treated teeth. Materials and Methods: Ninety extracted human upper canines were selected and randomly divided into nine groups (n=10): (G1) endodontically treated teeth without endodontic posts; (G2) glass-fiber post cemented with glass-ionomer cement; (G3) endodontic post by dual-cure composite resin (Rebilda DC); (G4) endodontic post by dual-cure composite resin (Cosmecore); (G5) endodontic post by dual-cure composite resin (Bis-Core); (G6) endodontic post by light-cure composite resin; (G7) glass-fiber post customized with flowable composite resin; (G8) glass-fiber post cemented with light-cure composite resin; (G9) glass-fiber post cemented with self-adhesive resin cement. After the post insertion, all specimens were subjected to mechanical (250,000 cycles) and thermocycling (6000 cycles, 5 °C/55 °C) and immediate loading at 45 degrees in a universal testing machine until fracture. The data were analyzed by one-way ANOVA and multiple comparisons using the Fisher LSD Method (p < 0 05). Results: The mean failure loads (±SD) for the groups ranged from 100.7 ± 22.6 N to 221.9 ± 48.9 N. The G1 group (without endodontic posts) had a higher fracture strength than all experimental groups (p < 0.001). Conclusions: Within the limitations, the light- and dual-cure post technique did not present lower fracture resistance values as compared to the conventional glass-fiber post.

7.
Dent Mater J ; 42(6): 878-885, 2023 Nov 29.
Artículo en Inglés | MEDLINE | ID: mdl-37793825

RESUMEN

The study evaluated the persistence of residues, bond strength and tags formation of a cementation system after post-space irrigation with different sodium hypochlorite-based irrigants. The groups were divided according to the irrigation protocol (DW: distilled water; SHS: sodium hypochlorite solution; SHG: sodium hypochlorite gel; and, SHT: sodium hypochlorite with surfactant). Forty roots (n=10) were used to evaluate the persistence of residues by scanning electron microscopy. Other forty roots were used to the push-out bond strength test, failure mode and tag formation analyses. Non-parametric data were submitted to Kruskal Wallis and Dunn tests, while parametric data were evaluated by one-way ANOVA. No difference was observed in the persistence of residues. DW showed the highest bond strength and tag formation. Type 2 failure mode was the most frequent in the experimental groups. Compared to control, SHT showed the best performance, since less negative effects on adhesive interface was observed.


Asunto(s)
Recubrimiento Dental Adhesivo , Técnica de Perno Muñón , Cementación/métodos , Hipoclorito de Sodio/farmacología , Hipoclorito de Sodio/química , Dentina , Irrigantes del Conducto Radicular , Cementos de Resina/química , Ensayo de Materiales
8.
Braz Dent J ; 34(4): 54-61, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37909642

RESUMEN

This study compared the pH and calcium ion release of calcium silicate- (Bio-C Temp) and calcium hydroxide-based (Ultracal XS) medications. Intracanal remnants of both medications were also evaluated using SEM-EDS after the removal protocol. Thirty-five bovine teeth were prepared. Fifteen were filled with Bio-C Temp and 15 with Ultracal XS. Five remained without intracanal medication (control group). Five samples from each experimental time (i.e.. 24, 72, and 168 hours) were used to measure pH and calcium ions release using a digital pH meter and microplate reader, respectively. Afterward, the peaks of the chemical elements composing both medications were analyzed in SEM-EDS. One-way ANOVA and Tukey's post hoc test analyzed the pH and calcium ion release data. Student's t-test compared the medications in each experimental time. SEM-EDS described the percentage of chemical elements in the samples. Bio-C Temp and Ultracal XS showed a significant pH increase from 24 to 168 hours (p<0.05). Ultracal XS showed a higher pH value at 24 hours than Bio-C Temp (p<0.05) but were similar at 72 and 168h (p > 0.05). Calcium ion release did not depend on the experimental period (p > 0.05). Bio-C Temp showed lower calcium ions release than Ultracal XS at 24 hours (p<0.05). SEM-EDS analyses showed the remains of both medications, but the concentration of Si, Al, and W ions was present only in the calcium silicate-based medication. Bio-C Temp presented alkaline pH and a satisfactory calcium ion release over the time. The remaining of both medications were present after the protocols for paste removal.


Asunto(s)
Calcio , Materiales de Obturación del Conducto Radicular , Animales , Bovinos , Cavidad Pulpar , Hidróxido de Calcio , Concentración de Iones de Hidrógeno , Vendajes , Análisis Espectral , Materiales de Obturación del Conducto Radicular/química
9.
Polymers (Basel) ; 14(19)2022 Sep 26.
Artículo en Inglés | MEDLINE | ID: mdl-36235967

RESUMEN

Resin-based composites (RBCs) have transformed restorative dentistry and its procedures. However, the characteristics of RBCs have been modified over the years to enhance the physical and chemical properties of the materials. This context raises the need for studies that evaluate whether the properties of the RBCs that are commercially available are clinically adequate with different curing modes. This study aimed to evaluate the mechanical behavior of commercial RBCs after undergoing different curing modes. Twenty-three RBCs of different classes were evaluated. For curing the specimens, a microwave (BMS45, Brastemp) (for 3 min at 450 W) and three LED units were used: an Emitter A Fit (Schuster (second generation)) (light-curing for 15 s with an irradiance of 1250 mW/cm2), VALO (Ultradent (third generation)) (light-curing for 15 s with an irradiance of 1100 mW/cm2), and Emitter Now Duo (Schuster (second generation)) (light-curing for 15 s with an irradiance of 1100 mW/cm2). A total of 670 RBC specimens of 8 mm in diameter and 1 mm in depth were obtained. Afterward, a biaxial flexure strength test was performed until the failure of the specimens, using a universal testing machine set at a speed of 0.5 mm/min. The same specimens were subjected to infrared spectroscopy for evaluating the degree of conversion. Tukey's test was used for multiple comparisons at a significance level of 5%. The light-curing mode did not affect the flexure strength of the RBCs (p > 0.05), but the type and shade of RBCs did so (p < 0.05). In conclusion, the type of RBC directly interferes with the mechanical behavior of the material. However, the curing modes within the same RBC did not change the mechanical properties.

10.
Neurophysiol Clin ; 52(4): 333-338, 2022 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-35945094

RESUMEN

We compared the effects of one versus two daily sessions of anodal transcranial direct current stimulation (a-tDCS) delivered to the left dorsolateral prefrontal cortex (DLPFC) for 10 days in a cohort of 30 women (mean age 28.0±6.92) with chronic migraine (CM, disease duration: 37.8±48.41 month). Participants were randomly allocated to three groups: a-tDCS 1-s Group received one daily a-tDCS session; a-tDCS 2-s Group received two daily a-tDCS sessions; Group SHAM received one daily session with a simulated (placebo) current. All participants were assessed before, after and one month after treatment, using the Migraine Disability Assessment, Montreal Cognitive Assessment, d2 Test of Attention, Trail Making Test (part B), Sequence of Letters and Numbers of the Wechsler Adult Intelligence Scale - III, and Nine Hole Peg Test. We found no difference between groups in the cognitive measures and motor dexterity. However, after treatment, a significant decrease in migraine-related disability was found for the a-tDCS 1-s Group. For all variables, no cumulative effects were observed in a-tDCS 2-s compared to the a-tDCS 1-s Group. The study findings provide preliminary results for future clinical trials designed to compare different intervals between tDCS sessions in CM.


Asunto(s)
Trastornos Migrañosos , Estimulación Transcraneal de Corriente Directa , Adulto , Cognición/fisiología , Corteza Prefontal Dorsolateral , Femenino , Humanos , Trastornos Migrañosos/terapia , Dolor , Corteza Prefrontal/fisiología , Estimulación Transcraneal de Corriente Directa/métodos , Adulto Joven
11.
Sci Rep ; 12(1): 1440, 2022 01 27.
Artículo en Inglés | MEDLINE | ID: mdl-35087138

RESUMEN

Neuropathic pain after brachial plexus injury (NPBPI) is a highly disabling clinical condition and is increasingly prevalent due to increased motorcycle accidents. Currently, no randomized controlled trials have evaluated the effectiveness of non-invasive brain stimulation techniques such as repetitive transcranial magnetic stimulation (rTMS) and transcranial direct-current stimulation (tDCS) in patients suffering from NPBPI. In this study, we directly compare the efficacy of 10-Hz rTMS and anodal 2 mA tDCS techniques applied over the motor cortex (5 daily consecutive sessions) in 20 patients with NPBPI, allocated into 2 parallel groups (active or sham). The order of the sessions was randomised for each of these treatment groups according to a crossover design and separated by a 30-day interval. Scores for "continuous" and "paroxysmal" pain (primary outcome) were tabulated after the last stimulation day and 30 days after. Secondary outcomes included the improvement in multidimensional aspects of pain, anxiety state and quality of life from a qualitative and quantitative approach. Active rTMS and tDCS were both superior to sham in reducing continuous (p < 0.001) and paroxysmal (p = 0.002; p = 0.02) pain as well as in multidimensional aspects of pain (p = 0.001; p = 0.002) and anxiety state (p = < 0.001; p = 0.005). Our results suggest rTMS and tDCS are able to treat NPBPI with little distinction in pain and anxiety state, which may promote the use of tDCS in brachial plexus injury pain management, as it constitutes an easier and more available technique.Clinical Trial Registration: http://www.ensaiosclinicos.gov.br/, RBR-5xnjbc - Sep 3, 2018.


Asunto(s)
Ansiedad/terapia , Plexo Braquial/lesiones , Neuralgia/terapia , Estimulación Transcraneal de Corriente Directa/métodos , Estimulación Magnética Transcraneal/métodos , Adulto , Ansiedad/etiología , Ansiedad/psicología , Estudios Cruzados , Método Doble Ciego , Femenino , Humanos , Masculino , Neuralgia/diagnóstico , Neuralgia/etiología , Neuralgia/psicología , Manejo del Dolor/métodos , Dimensión del Dolor/estadística & datos numéricos , Proyectos Piloto , Placebos , Calidad de Vida , Resultado del Tratamiento , Adulto Joven
12.
Brain Stimul ; 15(3): 780-788, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35568312

RESUMEN

BACKGROUND AND PURPOSE: Acute Respiratory Distress Syndrome (ADRS) due to coronavirus disease 2019 (COVID-19) has been associated with muscle fatigue, corticospinal pathways dysfunction, and mortality. High-Definition transcranial Direct Current Stimulation (HD-tDCS) may be used to attenuate clinical impairment in these patients. The HD-RECOVERY randomized clinical trial was conducted to evaluate the efficacy and safety of HD-tDCS with respiratory rehabilitation in patients with moderate to severe ARDS due to COVID-19. METHODS: Fifty-six critically ill patients were randomized 1:1 to active (n = 28) or sham (n = 28) HD-tDCS (twice a day, 30-min, 3-mA) plus respiratory rehabilitation for up to 10 days or until intensive care unit discharge. The primary outcome was ventilator-free days during the first 28 days, defined as the number of days free from mechanical ventilation. Furthermore, secondary outcomes such as delirium, organ failure, hospital length of stay and adverse effects were investigated. RESULTS: Active HD-tDCS induced more ventilator-free days compared to sham HD-tDCS. Patients in the active group vs in the sham group experienced lower organ dysfunction, delirium, and length of stay rates over time. In addition, positive clinical response was higher in the active vs sham group. There was no significant difference in the prespecified secondary outcomes at 5 days. Adverse events were similar between groups. CONCLUSIONS: Among patients with COVID-19 and moderate to severe ARDS, use of active HD-tDCS compared with sham HD-tDCS plus respiratory rehabilitation resulted in a statistically significant increase in the number of ventilator-free days over 28 days. HD-tDCS combined with concurrent rehabilitation therapy is a safe, feasible, potentially add-on intervention, and further trials should examine HD-tDCS efficacy in a larger sample of patients with COVID-19 and severe hypoxemia.


Asunto(s)
COVID-19 , Delirio , Síndrome de Dificultad Respiratoria , Estimulación Transcraneal de Corriente Directa , Enfermedad Crítica/terapia , Delirio/etiología , Humanos , Síndrome de Dificultad Respiratoria/terapia , SARS-CoV-2 , Estimulación Transcraneal de Corriente Directa/efectos adversos
13.
Front Immunol ; 12: 662307, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34354699

RESUMEN

The treatment of multibacillary cases of leprosy with multidrug therapy (MDT) comprises 12 doses of a combination of rifampicin, dapsone and clofazimine. Previous studies have described the immunological phenotypic pattern in skin lesions in multibacillary patients. Here, we evaluated the effect of MDT on skin cell phenotype and on the Mycobacterium leprae-specific immune response. An analysis of skin cell phenotype demonstrated a significant decrease in MRS1 (SR-A), CXCL10 (IP-10) and IFNG (IFN-γ) gene and protein expression after MDT release. Patients were randomized according to whether they experienced a reduction in bacillary load after MDT. A reduction in CXCL10 (IP-10) in sera was associated with the absence of a reduction in the bacillary load at release. Although IFN-γ production in response to M. leprae was not affected by MDT, CXCL10 (IP-10) levels in response to M. leprae increased in cells from patients who experienced a reduction in bacillary load after treatment. Together, our results suggest that CXCL10 (IP-10) may be a good marker for monitoring treatment efficacy in multibacillary patients.


Asunto(s)
Quimiocina CXCL10/sangre , Leprostáticos/uso terapéutico , Lepra/tratamiento farmacológico , Piel/inmunología , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Carga Bacteriana/efectos de los fármacos , Biomarcadores/sangre , Quimiocina CXCL10/inmunología , Quimioterapia Combinada , Femenino , Humanos , Leprostáticos/administración & dosificación , Lepra/inmunología , Masculino , Persona de Mediana Edad , Mycobacterium leprae/inmunología , Piel/microbiología , Piel/patología , Resultado del Tratamiento , Adulto Joven
14.
Nutr Cancer ; 62(3): 336-42, 2010.
Artículo en Inglés | MEDLINE | ID: mdl-20358471

RESUMEN

The aim of this study was to investigate the effect of daily coffee ingestion on hepatocarcinogenesis in rats submitted to the resistant hepatocyte (RH) model. During lactation, the dams were fed a control or a coffee-supplemented diet. After weaning, male pups followed the same dietary protocol and were submitted to the RH model. The animals were sacrificed at 110 days of life. Removal of the medial and left lateral lobes was used as mitogenic stimulus, and the liver regeneration was estimated. Morphometric analyses of preneoplastic lesions were carried out on liver histological sections submitted to the histochemical procedure of the glucose-6-phosphatase activity. The gamma-glutamyltranspeptidase (GGT) activity was analyzed in the homogenate of regenerated livers. Body weight, mass liver regeneration, and hepatic cell architecture were not affected by coffee ingestion. In the group of animals fed the coffee-supplemented diet, the number of persistent and remodeling nodules was reduced (85.5% and 70.5%, respectively). The hepatic area occupied by the persistent nodules was also reduced (92%). There was a reduction of 7.7% in the GGT activity in the group fed the coffee-supplemented diet, although not statistically significant. The results indicate that coffee modulates chemical hepatocarcinogenesis in rats.


Asunto(s)
Café , Neoplasias Hepáticas Experimentales/inducido químicamente , Animales , Peso Corporal , Femenino , Hígado/patología , Regeneración Hepática , Tamaño de los Órganos , Lesiones Precancerosas/inducido químicamente , Ratas , Ratas Wistar , gamma-Glutamiltransferasa/metabolismo
15.
J Chem Phys ; 132(20): 204301, 2010 May 28.
Artículo en Inglés | MEDLINE | ID: mdl-20515089

RESUMEN

We report cross sections for low-energy elastic electron scattering by pyrrole, obtained with the Schwinger multichannel method implemented with pseudopotentials. Our calculations indicate pi( *) shape resonances in the B(1) and A(2) symmetries, and two sigma( *) resonances in the A(1) symmetry (the system belongs to the C(2v) point group). The present assignments of pi( *) resonances are very close to those previously reported for the isoelectronic furan molecule, in agreement with electron transmission spectra. The lowest-lying sigma( *) anion is localized on the N-H bond and provides a dissociation coordinate similar to those found in the hydroxyl groups of organic acids and alcohols. This sigma(NH) ( *) resonance overlaps the higher-lying pi( *) resonance (possibly both pi( *) states) and could give rise to direct and indirect dissociation pathways, which arise from electron attachment to sigma( *) and pi( *) orbitals, respectively. The photochemistry of pyrrole and 9-H adenine is similar, in particular with respect to the photostability mechanism that allows for the dissipation of the photon energy, and we believe pyrrole would also be a suitable prototype for studies of dissociative electron attachment (DEA) to DNA bases. We point out the connection between the mechanisms of photostability and DEA since both arise from the occupation of sigma( *) and pi( *) orbitals in neutral excited states and in anion states, respectively.


Asunto(s)
Electrones/uso terapéutico , Fotoquímica/métodos , Pirroles/química , Simulación por Computador , ADN/química , Metabolismo Energético , Fotones/efectos adversos , Fotones/uso terapéutico
16.
Sci Rep ; 10(1): 18955, 2020 11 03.
Artículo en Inglés | MEDLINE | ID: mdl-33144646

RESUMEN

Transcranial Direct Current Stimulation (tDCS) has been used as an alternative treatment for pain reduction in fibromyalgia. In this study, in addition to behavioral measures, we analyzed oscillations in alpha 2 frequency band in the frontal, occipital, and parietal regions, in response to the application of two neuromodulation protocols in fibromyalgia. The study was a randomized, double-blind, placebo-controlled clinical trial with 31 women diagnosed with fibromyalgia. The participants were allocated to three groups with the anodic stimulation applied on the left motor cortex: Group 1, for five consecutive days; Group 2, for 10 consecutive days; and Group 3, sham stimulation for five consecutive days. Statistical analysis showed a reduction in pain intensity after treatment for groups in general [F (1.28) = 8.02; p = 0.008; η2 = 0.223], in addition to a reduction in alpha 2 in the frontal (p = 0.039; d = 0.384) and parietal (p = 0.021; d = 0.520) regions after the treatment on five consecutive days. We conclude that neuromodulation protocols produced similar effects on pain reduction, but differed with respect to the changes in the alpha 2 frequency band in the frontal and parietal regions.


Asunto(s)
Fibromialgia/terapia , Dolor/prevención & control , Adulto , Estimulación Encefálica Profunda , Método Doble Ciego , Estimulación Eléctrica , Terapia por Estimulación Eléctrica/métodos , Electroencefalografía , Electrofisiología , Femenino , Humanos , Persona de Mediana Edad , Neurociencias , Manejo del Dolor/métodos
17.
Chemosphere ; 240: 124910, 2020 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-31561159

RESUMEN

The micronucleus test has been applied for more than three decades in tadpoles, generating an early warning of environmental quality. In this study, we reviewed 48 articles on the micronucleus test in tadpoles, published between 1987 and 2018. The findings reveal that pesticides have been the main topic discussed in the induction of micronucleus and other nuclear abnormalities in anuran larvae to the detriment of the widespread use of compounds used in agriculture. In addition to pesticides, a number of other xenobiotic agents have been targeted for genotoxic damage, such as heavy metals, radiation and wastewater. An appeal is reported to environmental contaminants, which when released naturally into the environment or because of human activities may contaminate aquatic habitats, threatening populations of tadpoles that depend on these environments for their survival. Larvae can bioaccumulate these contaminants that cause progressive impacts, ranging from DNA damage to metamorphosis delays, as well as malformations. We found that Argentina is the main driving force for the application of this test in anuran larvae along with Brazil. Different erythrocyte malformations have been reported for the erythrocyte nuclear abnormalities test, binucleated cells, nuclear buds, notched, lobed, reniform, nuclear bebbled, anucleated, picnotic and apoptotic cells are the most cited. In summary, the presence of chemical or physical agents, along with other disturbances of the habitat, can have a significant impact on the life history of the species, contributing to the decline of anuran populations.


Asunto(s)
Anuros/genética , Ecotoxicología/tendencias , Eritrocitos/efectos de los fármacos , Larva/efectos de los fármacos , Larva/genética , Pruebas de Micronúcleos , Agricultura , Animales , Argentina , Brasil , Daño del ADN , Ecosistema , Monitoreo del Ambiente/métodos , Contaminación Ambiental , Eritrocitos/patología , Eritrocitos/fisiología , Metales Pesados/toxicidad , Metamorfosis Biológica/efectos de los fármacos , Publicaciones Seriadas , Contaminantes Químicos del Agua/toxicidad
18.
Front Immunol ; 11: 1493, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32849508

RESUMEN

In HIV-infected individuals, a paradoxical clinical deterioration may occur in preexisting leprosy when highly active antiretroviral therapy (HAART)-associated reversal reaction (RR) develops. Leprosy-HIV co-infected patients during HAART may present a more severe form of the disease (RR/HIV), but the immune mechanisms related to the pathogenesis of leprosy-HIV co-infection remain unknown. Although the adaptive immune responses have been extensively studied in leprosy-HIV co-infected individuals, recent studies have described that innate immune cells may drive the overall immune responses to mycobacterial antigens. Monocytes are critical to the innate immune system and play an important role in several inflammatory conditions associated with chronic infections. In leprosy, different tissue macrophage phenotypes have been associated with the different clinical forms of the disease, but it is not clear how HIV infection modulates the phenotype of innate immune cells (monocytes or macrophages) during leprosy. In the present study, we investigated the phenotype of monocytes and macrophages in leprosy-HIV co-infected individuals, with or without RR. We did not observe differences between the monocyte profiles in the studied groups; however, analysis of gene expression within the skin lesion cells revealed that the RR/HIV group presents a higher expression of macrophage scavenger receptor 1 (MRS1), CD209 molecule (CD209), vascular endothelial growth factor (VEGF), arginase 2 (ARG2), and peroxisome proliferator-activated receptor gamma (PPARG) when compared with the RR group. Our data suggest that different phenotypes of tissue macrophages found in the skin from RR and RR/HIV patients could differentially contribute to the progression of leprosy.


Asunto(s)
Terapia Antirretroviral Altamente Activa/efectos adversos , Infecciones por VIH/inmunología , VIH-1/fisiología , Lepra/inmunología , Macrófagos/inmunología , Monocitos/inmunología , Mycobacterium leprae/fisiología , Adulto , Anciano , Diferenciación Celular , Coinfección , Progresión de la Enfermedad , Femenino , Infecciones por VIH/complicaciones , Infecciones por VIH/terapia , Humanos , Lepra/complicaciones , Lepra/terapia , Masculino , Persona de Mediana Edad , Receptores Depuradores de Clase A/metabolismo
19.
Anal Biochem ; 385(1): 65-8, 2009 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-19027708

RESUMEN

We describe an assay for the enzyme Na/K-ATPase in intact guinea pig livers perfused through the portal vein with modified Hank's solution. The model uses the measurement of non-radioactive rubidium ion incorporation by liver cells, both in the absence and in the presence of the specific Na/K-ATPase inhibitor ouabain, followed by a rinsing procedure with cold saline. The concentration of Rb+ in acid-digested liver lobes was measured by atomic emission spectrometry and Na/K pump activity was calculated by the difference between the incorporation of Rb+ in the absence and in the presence of ouabain. The optimal conditions for Rb+ incorporation were: perfusion flow rate, 3 ml/min per liver; perfusion time at 37 degrees C, 60 min; rinsing time with cold saline, 5-10 min; and concentration of ouabain, 3 mM. The calculated ouabain IC(50) was 100 microM. The major advantage of this model is the possibility of testing experimental drugs affecting this enzyme in conditions close to those in the intact organ.


Asunto(s)
Hígado/enzimología , ATPasa Intercambiadora de Sodio-Potasio/metabolismo , Animales , Inhibidores Enzimáticos/farmacología , Cobayas , Soluciones Isotónicas , Hígado/irrigación sanguínea , Ouabaína/farmacología , Flujo Sanguíneo Regional , Rubidio/análisis , Rubidio/metabolismo , ATPasa Intercambiadora de Sodio-Potasio/antagonistas & inhibidores , Espectrofotometría Atómica , Factores de Tiempo
20.
Eur J Obstet Gynecol Reprod Biol ; 139(1): 79-85, 2008 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-17933453

RESUMEN

BACKGROUND: The objective of this study was to evaluate the correlation between the 2001 Bethesda classification of endocervical glandular abnormalities and histological diagnosis. STUDY DESIGN: A series of 155 women with endocervical glandular abnormalities on cervical smears were included: 91 with atypical glandular cells (AGC) not otherwise specified (NOS), 15 with AGC-favor neoplastic (FN); 35 with AGC associated with high-grade squamous intraepithelial lesion (HSIL) as combined diagnosis and 14 with adenocarcinoma in situ (AIS). RESULTS: Histological outcome of squamous neoplasias (CIN 2 or worse) and adenocarcinoma were significantly associated with AGC-FN and AIS, taking as reference AGC-NOS, and more associated with AIS than AGC-FN. Similar associations were observed for histological outcome of adenocarcinoma, but no association was observed for only squamous neoplasia. Histological outcome of CIN2 or worse was strongly associated with AGC when HSIL was also present, but no association was observed with only for adenocarcinoma histological outcome. CONCLUSIONS: AGC-NOS, AGC-FN and AIS cytological diagnosis represent a progressively increasing association with neoplastic diagnosis, due to progressively increasing association with adenocarcinoma. Histological outcome of squamous neoplasia is frequent but does not differ with these cytological interpretations. The presence of HSIL associated with AGC represents greater probability of squamous neoplasia but not adenocarcinoma.


Asunto(s)
Adenocarcinoma/patología , Carcinoma de Células Escamosas/patología , Displasia del Cuello del Útero/patología , Neoplasias del Cuello Uterino/patología , Adenocarcinoma/diagnóstico , Carcinoma de Células Escamosas/diagnóstico , Femenino , Humanos , Neoplasias del Cuello Uterino/diagnóstico , Frotis Vaginal/métodos , Displasia del Cuello del Útero/diagnóstico
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA