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1.
Arch Biochem Biophys ; 731: 109424, 2022 11 30.
Article in English | MEDLINE | ID: mdl-36220378

ABSTRACT

As in most enveloped RNA viruses, the Respiratory Syncytial Virus Matrix (RSV-M) protein plays key roles in viral assembly and uncoating. It also plays non-structural roles related to transcription modulation through nucleo-cytoplasmic shuttling and nucleic acid binding ability. We dissected the structural and conformational changes underlying the switch between multiple functionalities, identifying Ca2+ binding as a key factor. To this end, we tackled the analysis of M's conformational stability and equilibria. While in silico calculations predict two potential calcium binding sites per protomer, purified RSV-M dimer contains only one strongly bound calcium ion per protomer. Incubation of RSV-M in the presence of excess Ca2+ leads to an increase in the thermal stability, confirming additional Ca2+ binding sites. Moreover, mild denaturant concentrations trigger the formation of higher order oligomers which are otherwise prevented under Ca2+ saturation conditions, in line with the stabilizing effect of the additional low affinity binding site. On the other hand, Ca2+ removal by chelation at pH 7.0 causes a substantial decrease in the thermal stability leading to the formation of amorphous, spherical-like aggregates, as assessed by TEM. Even though the Ca2+ content modulates RSV-M oligomerization propensity, it does affect its weak RNA binding ability. RSV-M undergoes a substantial conformational change at pHs 4.0 to 5.0 that results in the exposure of hydrophobic surfaces, an increase beta sheet content but burial of tryptophan residues. While low ionic strength promotes dimer dissociation at pH 4.0, physiological concentrations of NaCl lead to the formation of soluble oligomers smaller than 400 kDa at pH 4.0 or insoluble aggregates with tubular morphology at pH 5.0, supporting a fine tuning by pH. Furthermore, the dissociation constants estimated for the low- and high affinity calcium binding sites are 13 µM and 58 nM, respectively, suggesting an intracellular calcium sensing mechanism of RSV-M upon infection. We uncover a finely tuned interplay between calcium binding, ionic strength, and pH changes compatible with the different cellular compartments where M plays key roles, revealing diverse conformational equilibria, oligomerization, and high order structures, required to stabilize the virion particle by a layer of molecules positioned between the membrane and the nucleocapsid.


Subject(s)
Calcium , Respiratory Syncytial Virus, Human , Protein Subunits , Respiratory Syncytial Virus, Human/chemistry , Virus Assembly , Osmolar Concentration , Protein Binding
2.
Arch Biochem Biophys ; 671: 77-86, 2019 08 15.
Article in English | MEDLINE | ID: mdl-31229488

ABSTRACT

Virus from the Mononegavirales order share common features ranging from virion structure arrangement to mechanisms of replication and transcription. One of them is the way the nucleoprotein (N) wraps and protects the RNA genome from degradation by forming a highly ordered helical nucleocapsid. However, crystal structures from numerous Mononegavirales reveal that binding to the nucleoprotein results in occluded nucleotides that hinder base pairing necessary for transcription and replication. This hints at the existence of alternative conformations of the N protein that would impact on the protein-RNA interface, allowing for transient exposure of the nucleotides without complete RNA release. Moreover, the regulation between the alternative conformations should be finely tuned. Recombinant expression of N from the respiratory syncytial virus form regular N/RNA common among all Mononegavirales, and these constitute an ideal minimal unit for investigating the mechanisms through which these structures protect RNA so efficiently while allowing for partial accessibility during transcription and replication. Neither pH nor high ionic strength could dissociate the RNA but led to irreversible aggregation of the nucleoprotein. Low concentrations of guanidine chloride dissociated the RNA moiety but leading to irreversible aggregation of the protein moiety. On the other hand, high concentrations of urea and long incubation periods were required to remove bound RNA. Both denaturants eventually led to unfolding but converged in the formation of an RNA-free ß-enriched intermediate species that remained decameric even at high denaturant concentrations. Although the N-RNA rings interact with the phosphoprotein P, the scaffold of the RNA polymerase complex, this interaction did not lead to RNA dissociation from the rings in vitro. Thus, we have uncovered complex equilibria involving changes in secondary structure of N and RNA loosening, processes that must take place in the context of RNA transcription and replication, whose detailed mechanisms and cellular and viral participants need to be established.


Subject(s)
Nucleocapsid Proteins/metabolism , RNA, Viral/metabolism , Hydrogen-Ion Concentration , Molecular Dynamics Simulation , Nucleic Acid Conformation , Nucleocapsid Proteins/chemistry , Osmolar Concentration , Protein Binding , Protein Structure, Secondary , RNA Stability , RNA, Viral/chemistry , Respiratory Syncytial Virus, Human/chemistry , Temperature , Thermodynamics
3.
Rev Port Pneumol (2006) ; 22(4): 202-8, 2016.
Article in English | MEDLINE | ID: mdl-27052354

ABSTRACT

UNLABELLED: Sleep disturbance has been described in cystic fibrosis (CF) patients as relevant to clinical and lung function predictive factors helping to improve the diagnosis and early intervention. Related paediatric studies are scarce. OBJECTIVE: To describe respiratory sleep disturbance (RSD) and its association with spirometric indices in a population of CF children. A second aim was to determine if spirometric indices and wake-time SpO2 are predictors of sleep disturbance. METHODS: A cross-sectional study involving 33CF paediatric patients. All participants underwent in-lab polysomnography (PSG), pulse oximetry and spirometry. A standardized sleep questionnaire was completed for each patient. Two subgroups were considered: I - Normal (FEV1>-1.64 z-score); II - Obstructed (FEV1≤-1.64 z-score). RESULTS: Participant's median age was 12 (6-18) years, 16 (48.5%) were male. Twenty-nine patients (87.9%) presented sleep complaints. Sleep efficiency was reduced; sleep latency and waking after sleep onset (WASO) increased. N1 increased, N2, N3, REM and awakenings were normal. The apnoea-hypopnoea index was 0.6/h (sd 0.9); respiratory disturbance index (RDI) was 6.6/h (sd 5.2). Mean awaking (97% (sd 1.1)) and sleep SpO2 (95% (sd 2.7)) were normal; mean nocturnal oximetry desaturation index was 2.36/h; minimal nocturnal SpO2 was 89% (sd 4.1). We found associations between mean nocturnal SPO2 and mean values of FEV1 (r=0.528; p=0.002) and FEF25-75 (r=0.426; p=0.013). There were significant differences in nocturnal SpO2 between normal and obstructed patients (p<0.000). PSG data correlated with the questionnaire answers for night awakenings and WASO (p=0.985) and difficult breathing during sleep and RDI (p=0.722). This study points to most CF children having sleep complaints, and highlights the correlation between subjective assessment of sleep and PSG and spirometric results. Awake-time SpO2 and spirometric values are possible risk predictors for nocturnal desaturation.


Subject(s)
Cystic Fibrosis/complications , Respiration Disorders/etiology , Sleep Wake Disorders/etiology , Adolescent , Child , Cross-Sectional Studies , Cystic Fibrosis/physiopathology , Female , Humans , Male , Oximetry , Polysomnography , Prospective Studies , Respiration Disorders/physiopathology , Sleep Wake Disorders/physiopathology , Spirometry
4.
J Clin Pediatr Dent ; 39(1): 27-9, 2014.
Article in English | MEDLINE | ID: mdl-25631722

ABSTRACT

The aim of the present study was to describe a clinical protocol for the treatment of white spots with the use of an abrasive material. A four-year-old patient presented with a white spot on tooth 51 and a white spot associated with a carious lesion in the cervical region of tooth 52. Treatment was planned with microabrasion and restoration of the upper right lateral incisor. Prophylaxis was first performed, followed by protection with a dental dam and the application of the abrasive material (silicon carbide and hydrochloric acid 6%). Five applications were needed to remove the spots. The restoration of the upper right lateral incisor was then performed with a resin composite. A good esthetic outcome was achieved and both the patient and her guardians were satisfied with the results. Microabrasion is a conservative treatment option that achieves satisfactory results with regard to tooth color.


Subject(s)
Dental Caries/therapy , Enamel Microabrasion/methods , Carbon Compounds, Inorganic/therapeutic use , Child, Preschool , Clinical Protocols , Composite Resins/chemistry , Dental Materials/chemistry , Dental Prophylaxis , Dental Restoration, Permanent/instrumentation , Dental Restoration, Permanent/methods , Esthetics, Dental , Humans , Hydrochloric Acid/therapeutic use , Incisor/pathology , Male , Rubber Dams , Silicon Compounds/therapeutic use , Tooth Cervix/pathology
5.
Appl Radiat Isot ; 82: 322-4, 2013 Dec.
Article in English | MEDLINE | ID: mdl-24140984

ABSTRACT

[(99m)Tc]pentetate ([(99m)Tc]DTPA) is the most commonly used radiopharmaceutical renography agent. The aim of this work was to validate an alternative method for assessing [(99m)Tc]DTPA radiochemical purity (RCP), according to the ICH Q2(R1) guidance: "Validation of Analytical Procedures". The proposed method is composed of two chromatographic systems. System A is a miniaturized system of thin layer chromatography (TLC) silica gel impregnated aluminum strips as stationary phase (SP) and distilled water as mobile phase (MP). System B consists of Whatman 1 paper strips as SP and methyl ethyl ketone as MP. Results indicate that the proposed RCP method has been validated, as it is specific, precise, accurate, linear and robust. Therefore, it can be used as an alternative method for RCP quality control purposes and as stability indicator as well.


Subject(s)
Radiopharmaceuticals/standards , Technetium Tc 99m Pentetate/standards , Butanones , Chromatography, Paper/methods , Chromatography, Paper/standards , Chromatography, Thin Layer/methods , Chromatography, Thin Layer/standards , Drug Stability , Humans , Quality Control , Radioisotope Renography
6.
Acta Trop ; 128(1): 36-40, 2013 Oct.
Article in English | MEDLINE | ID: mdl-23792228

ABSTRACT

The objective of this study is to describe the nutritional status of adult and elderly patients with American Tegumentary Leishmaniasis (ATL). It was conducted a longitudinal study in 68 adult and elderly patients with ATL treating at the Surveillance Leishmaniasis Laboratory at the Evandro Chagas Clinical Research Institute, Oswaldo Cruz Foundation (Fiocruz), from 2009 to 2012. The nutritional assessment included the body mass index (BMI) and serum albumin levels. The clinical evolution (epithelialization and wound healing) was measured up to two years after ATL treatment. Most of the sample was composed of men (71%), adults (73%), with household income of 1-5 minimum wages (79%), and incomplete elementary school (48.5%). The predominant ATL form was cutaneous (72%), and 39% presented comorbidities, the most frequent was hypertension (30.8%). The most prevalent clinical and nutritional events were: recent decrease in food intake (23.9%); nasal obstruction (22.1%); oral ulcer (14.7%), anorexia and dysphagia (13.2% each) and odynophagia (10.3%). The total healing time was 115.00 (IR=80-230) days for skin lesions, and 120.00 (IR=104.50-223.50) days for mucous membrane lesions. Low body weight in 10%, and hypoalbuminemia in 12% of the patients have been observed. Low body weight was associated with age, mucosal leishmaniasis (ML), nasal obstruction, recent decrease in food intake and hypoalbuminemia. As for serum albumin depletion, association with the ML, dyspnea, dysphagia, odynophagia, recent decrease in food intake, absence of complete healing of the skin lesions, and increased healing time for mucous membrane lesions, was observed. The ML and their events that affect the alimentary intake have been related to the impairment of the nutritional status. Additionally, serum albumin depletion negatively affected the healing of the lesions, suggesting that a nutritional intervention can increase the effectiveness of the ATL treatment.


Subject(s)
Antiprotozoal Agents/therapeutic use , Leishmaniasis, Cutaneous/drug therapy , Leishmaniasis, Cutaneous/pathology , Nutritional Status , Adult , Aged , Aged, 80 and over , Body Mass Index , Female , Humans , Longitudinal Studies , Male , Middle Aged , Serum Albumin/analysis , Treatment Outcome , Wound Healing , Young Adult
7.
Farm Hosp ; 37(1): 65-71, 2013.
Article in Spanish | MEDLINE | ID: mdl-23461502

ABSTRACT

The Spanish Pharmacovigilance System for Medicinal Products for Human Use, integrated by regional centers of pharmacovigilance coordinated by the Spanish Agency for Medicines and Health Products, is responsible for developing the Program of Spontaneous Reporting of Suspected Adverse Drug Reactions in our country. Although, until now, reports were only requesting to health professionals, the current understanding of the role of patients in the clinical setting and the experience gained in other countries of our environment, have demonstrated the convenience of developing active participation systems to patients in the reporting of suspected adverse drug reactions. In addition, this is taking into account in the new European legislation on pharmacovigilance.


Subject(s)
Adverse Drug Reaction Reporting Systems/organization & administration , Drug-Related Side Effects and Adverse Reactions/epidemiology , Patient Participation , Pharmacovigilance , Adverse Drug Reaction Reporting Systems/legislation & jurisprudence , Drug Labeling/legislation & jurisprudence , Europe , Government Agencies/economics , Government Agencies/legislation & jurisprudence , Government Agencies/organization & administration , Humans , Internet , Patient Participation/legislation & jurisprudence , Postal Service , Safety-Based Drug Withdrawals/legislation & jurisprudence , Self Report , Spain/epidemiology , Telephone , World Health Organization
8.
Farm. hosp ; 37(1): 65-71, ene.-feb. 2013. tab
Article in Spanish | IBECS | ID: ibc-115649

ABSTRACT

El Sistema Español de Farmacovigilancia de medicamentos de uso humano, integrado por los centros autonómicos de farmacovigilancia coordinados por la Agencia Española de Medicamentos y Productos Sanitarios, se encarga del desarrollo en nuestro país del Programa de Notificación Espontánea de Sospechas de Reacciones Adversas a Medicamentos. Aunque hasta ahora se solicitaba la notificación únicamente a los profesionales sanitarios, el entendimiento actual del papel de los pacientes en la relación clínica y la experiencia obtenida ya en otros países de nuestro entorno, han puesto de manifiesto la conveniencia de desarrollar sistemas de participación activa de los pacientes en la notificación de sospechas de reacciones adversas a medicamentos. Así lo recoge además la nueva normativa europea en materia de Farmacovigilancia (AU)


The Spanish Pharmacovigilance System for Medicinal Products for Human Use, integrated by regional centers of pharmacovigilance coordinated by the Spanish Agency for Medicines and Health Products, is responsible for developing the Program of Spontaneous Reporting of Suspected Adverse Drug Reactions in our country. Although, until now, reports were only requesting to health professionals, the current understanding of the role of patients in the clinical setting and the experience gained in other countries of our environment, have demonstrated the convenience of developing active participation systems to patients in the reporting of suspected adverse drug reactions. In addition, this is taking into account in the new European legislation on pharmacovigilance (AU)


Subject(s)
Humans , Notification , /epidemiology , Pharmacovigilance , Patient Participation/statistics & numerical data
9.
Maturitas ; 74(1): 74-8, 2013 Jan.
Article in English | MEDLINE | ID: mdl-23121774

ABSTRACT

AIM: To analyze the time trends in anti-osteoporosis medications consumption in Spain between 2000 and 2008 and the influence on such consumption induced by the Information Sheets related to the safety of menopausal hormone therapy and strontium ranelate published by the Spanish Agency of Medicines and Health Products (AEMPS). METHODS: Purchase data of anti-osteoporosis medications from 2000 to 2008 were obtained from the Spanish Ministry of Health. This information includes the pharmacy sales data of medicinal products reimbursed by the Spanish National Health Service. Anti-osteoporosis medications consumption data were expressed as defined daily dose per 1 000 inhabitants per day in women aged 50 or more. RESULTS: During the study period, anti-osteoporosis medications consumption showed a continuous increase. The greatest increase was observed with bisphosphonates, particularly alendronate and risedronate in their weekly formulations. Strontium ranelate consumption was low but continuously increased and new information concerning its safety in 2007 had no effect on its consumption. The use of menopausal hormone therapy remained stable until 2003, and from then presented a continuous decrease until 2008. Raloxifene utilization increased from 2000 to 2004 and decreased thereafter. Calcitonin utilization decreased uninterruptedly and teriparatide was infrequently used. CONCLUSION: This study reports a marked change in osteoporosis treatment in Spain, which includes an important increase in anti-osteoporosis medication use, particularly of bisphosphonates and a decrease in menopausal hormone therapy use secondary to the new information about their safety.


Subject(s)
Bone Density Conservation Agents/therapeutic use , Osteoporosis, Postmenopausal/drug therapy , Estrogen Replacement Therapy , Female , Humans , Middle Aged , Spain
10.
Br J Health Psychol ; 16(4): 779-98, 2011 Nov.
Article in English | MEDLINE | ID: mdl-21988064

ABSTRACT

OBJECTIVES: There is a debate on the determinants of smoking behaviour, their relative impact, and how impacts are exerted. This longitudinal study is on the relations among social influence, intention to smoke, and smoking behaviour, controlling for attitude and self-efficacy. DESIGN AND METHODS: A model combining parents and peers with subjective and descriptive norms, resulting in four factors, was used to assess social influence. Data were collected at the beginning of the 7th(-T1), 8th(-T2), and 9th(-T3) school years, concerning 578 students (M(age) = 13.04 at T1). Structural Equation Modelling was used to test longitudinal effects. RESULTS: Variances explained by the model were high: R(2) (intention-T2) = .65, R(2) (behaviour-T2) = .67, and R(2) (behaviour-T3) = .76. Longitudinal analyses confirmed the effects of social influence on intention and behaviour. These effects on behaviour were direct and indirect (peers' and parents' descriptive norms in both cases). Descriptive norms had a stronger effect on behaviour than subjective norms. Peers' effect on behaviour was stronger than parents', but peers' effect was exerted only through descriptive norms while parents' effect was exerted through both norms. The intention effect on behaviour was not as detached as expected and its role of full mediator between other variables' effects on behaviour was not confirmed, since descriptive norms and self-efficacy had also a mediation role. CONCLUSIONS: Results show direct and indirect effects of social influence on behaviour. Descriptive norms are an important variable to operationalize social influence. Peers and parents exert influence on adolescents' intention and behaviour through different processes. The impact of intention on behaviour is not as important as expected.


Subject(s)
Intention , Parent-Child Relations , Peer Group , Smoking , Adolescent , Adolescent Behavior , Child , Female , Humans , Longitudinal Studies , Male , Models, Statistical , Spain , Surveys and Questionnaires
11.
Pharmacoepidemiol Drug Saf ; 20(10): 1080-7, 2011 Oct.
Article in English | MEDLINE | ID: mdl-21751292

ABSTRACT

PURPOSE: Previous publications have linked Herbalife® products to hepatotoxicity. The identification of earlier cases in which the culprit agent could not be established raised the hypothesis of a possible contamination of some specific batches of Herbalife products. METHODS: We searched the Spanish Pharmacovigilance Centres' database of adverse reactions for reports of liver injury associated with the use of Herbalife products from 2003, when the first case was submitted, through September 2010. RESULTS: The search resulted in 20 reports of liver damage (mean age, 49 years; 16 women), with 12 patients (60%) requiring hospitalization. Hepatocellular damage predominated, and nine (53%) of the hepatocellular cases with bilirubin values were jaundiced, fulfilling the Hy's law criteria, which increases the risk for serious outcomes. Two patients experienced a positive rechallenge. One patient developed cirrhosis, whereas all the others recovered. Causality assessment by the Karch and Lasagna modified algorithm showed a category of definite in 1 case, probable in 14, and possible in 5. Analysis of the different Herbalife products that each patient had taken did not enable us to identify any commonly known hepatotoxic ingredient. CONCLUSIONS: Our results support the relationship between the consumption of Herbalife products and hepatotoxicity, underscore the concern regarding the liver-related safety of this dietary supplement, and emphasize the need to establish further regulatory measures.


Subject(s)
Chemical and Drug Induced Liver Injury/epidemiology , Dietary Supplements/adverse effects , Liver Cirrhosis/etiology , Pharmacovigilance , Adult , Bilirubin/metabolism , Chemical and Drug Induced Liver Injury/etiology , Drug-Related Side Effects and Adverse Reactions/epidemiology , Ephedra/adverse effects , Female , Humans , Liver , Liver Cirrhosis/epidemiology , Male , Middle Aged , Spain/epidemiology
12.
Rev Port Pneumol ; 17(1): 20-6, 2011.
Article in English, Portuguese | MEDLINE | ID: mdl-21251480

ABSTRACT

INTRODUCTION: Tobacco smoke is a risk factor for Chronic Obstructive Pulmonary Disease and a major public health problem. Prenatal maternal smoking and post-natal environmental tobacco smoke (ETS) lead to dose-dependent decrease in lung function and respiratory morbidity. Influence of different socioeconomic indicators and ETS in the home has also been suggested. METHODS: Data on 313 children (52 % male) from 4 public schools in Lisbon was analyzed [1st (46 %) and 4th graders]. ETS assessment and respiratory symptoms were based on a self-answered questionnaire. All children performed standard spirometry in the school setting and 54 % were acceptable according to ATS/ERS criteria. Descriptive and bivariate analysis of the most relevant variables was done, followed by multiple logistic regression analysis adjusted to the variables with clinical/statistical relevance. RESULTS: ETS in the home was found in 41 % (maternal smoking during pregnancy 18 %, smoking mother 32 %, smoking father 38 %). Smoking fathers had lower education and less qualified occupation. Cough was more frequent in children with a smoking mother (adjusted OR = 2.1 95CI 1.1-4.0) and wheezing in children with maternal smoking during pregnancy and smoking parents. All differences were significant (p < 0.05). No association was found between parental education and cough/wheeze or ETS and respiratory infections/asthma/decreased spirometric values. CONCLUSIONS: Children in Lisbon are frequently exposed to ETS which results in significant respiratory morbidity. Targeted interventions must have social conditions in consideration. In this study, field spirometry was not helpful in early detection of lung function disability in children associated with ETS.


Subject(s)
Environmental Exposure/adverse effects , Respiratory Tract Diseases/etiology , Tobacco Smoke Pollution/adverse effects , Adolescent , Air Pollution , Child , Child, Preschool , Environmental Exposure/statistics & numerical data , Female , Humans , Male , Respiratory Tract Diseases/epidemiology , Retrospective Studies , Tobacco Smoke Pollution/statistics & numerical data
13.
J Laryngol Otol ; 124(10): 1056-60, 2010 Oct.
Article in English | MEDLINE | ID: mdl-20537206

ABSTRACT

OBJECTIVE: To evaluate dizziness in patients receiving meglumine antimoniate for the treatment of mucosal leishmaniasis. MATERIALS AND METHODS: We retrospectively studied 127 patients treated at the Laboratory of Leishmaniasis Surveillance, Evandro Chagas Clinical Research Institute, Oswaldo Cruz Foundation, Rio de Janeiro, Brazil, between 1 January 1989 and 31 December 2004. RESULTS: A low dose of meglumine antimoniate (5 mg/kg/day) was used in 86.6 per cent of patients; a dose of 10 mg/kg/day or higher was used in 13.4 per cent of patients. Dizziness was reported by 4.7 per cent of patients. The adjusted odds ratios were 7.37 for dizziness in female patients, 4.9 for dizziness in patients aged 60 years or older, and 7.77 for dizziness in the presence of elevated serum lipase. CONCLUSION: We suggest that dizziness may be a side effect of meglumine antimoniate, particularly in elderly individuals, in females and in patients with elevated serum lipase.


Subject(s)
Antiprotozoal Agents/adverse effects , Dizziness/chemically induced , Leishmaniasis, Mucocutaneous/drug therapy , Meglumine/adverse effects , Organometallic Compounds/adverse effects , Adolescent , Adult , Age Distribution , Aged , Aged, 80 and over , Antiprotozoal Agents/administration & dosage , Brazil/epidemiology , Child , Child, Preschool , Dizziness/epidemiology , Dose-Response Relationship, Drug , Female , Humans , Leishmaniasis, Mucocutaneous/epidemiology , Lipase/blood , Male , Meglumine/administration & dosage , Meglumine Antimoniate , Middle Aged , Odds Ratio , Organometallic Compounds/administration & dosage , Retrospective Studies , Risk Factors , Sex Distribution , Young Adult
14.
Neuroscience ; 168(3): 831-41, 2010 Jul 14.
Article in English | MEDLINE | ID: mdl-20412834

ABSTRACT

Neurotransmitter serotonin (5-HT) released from descending pain modulation pathways to the dorsal horn is crucial to spinal nociception processing. This study sought to gain insight into the modulatory roles of specific serotonin receptor subtypes in experimentally induced neuropathic pain. In rats subjected to spinal nerve ligation (SNL) surgery, we recorded field potentials evoked in the spinal dorsal horn by C fibre-input, during spinal superfusion with subtype-selective drugs. In neuropathic rats, subtype 5-HT1A agonist 8-OH-DPAT (100 nM) was found to potently depress evoked field potentials, as opposed to 5-HT2A or 5-HT2B subtype agonists TCB-2 (100 nM) or BW 723C86 (1 microM), respectively, which consistently enhanced evoked potentials. All three failed to alter spinal field potentials in sham operated rats. CP 94253 (1 microM), WAY 161503 (1 mM) or SR 57227 (at 1 microM in SNL rats, and 100 microM in sham rats), selective agonists for 5-HT1B, 5-HT2C and 5-HT3 receptors, respectively, significantly depressed evoked field potentials in both animal groups. The 5-HT4 agonist RS 67333 (1 microM) was depressant only in sham operated animals. Only after SNL, spinal superfusion with 5-HT1A- or 5-HT1B receptor-antagonists (S)-WAY 100135 (100 microM) or SB 224289 (100 microM), respectively, disinhibited C fibre-evoked potentials, whereas 5-HT2A or 5-HT2B receptor-antagonists 4F 4PP (100 microM) or SB 204741 (100 microM) depressed evoked potentials, suggesting tonic activity of all four subtypes as a consequence of experimental nerve injury. The present findings reveal profound subtype-specific changes in the functional modulatory activities of spinal serotonin receptors following peripheral nerve injury. In particular, spinal hyperexcitation promoted by receptors 5-HT2A and 5-HT2B is suggested as a novel pathogenic pathway contributing to neuropathic pain.


Subject(s)
Nerve Fibers, Unmyelinated/physiology , Pain/physiopathology , Receptors, Serotonin/physiology , Spinal Cord/physiopathology , Spinal Nerves/injuries , Animals , Evoked Potentials , Male , Myelin Sheath/physiology , Neuronal Plasticity , Rats , Rats, Sprague-Dawley , Synaptic Transmission
15.
Parasite Immunol ; 32(4): 285-95, 2010 Apr.
Article in English | MEDLINE | ID: mdl-20398229

ABSTRACT

Skin inflammation plays an important role during the healing of American tegumentary leishmaniasis (ATL), the distribution of cells in active lesions may vary according to disease outcome and parasite antigens in ATL scars have already been shown. We evaluated by immunohistochemistry, 18 patients with 1- or 3-year-old scars and the corresponding active lesions and compared them with healthy skin. Small cell clusters in scars organized as in the active lesions spreaded over the fibrotic tissue were detected, as well as close to vessels and cutaneous glands, despite a reduction in the inflammatory process. Analysis of 1-year-old scar tissue showed reduction of NOS2, E-selectin, Ki67, Bcl-2 and Fas expression. However, similar percentages of lymphocytes and macrophages were detected when compared to active lesions. Only 3-year-old scars showed reduction of CD3(+), CD4(+) and CD8(+)T cells, in addition to reduced expression of NOS2, E-selectin, Ki67 and BCl-2. These results suggest that the pattern of cellularity of the inflammatory reaction observed in active lesions changes slowly even after clinical healing. Analysis of 3-year-old scars showed reduction of the inflammatory reaction as demonstrated by decrease in inflammatory cells and in the expression of cell-activity markers, suggesting that the host-parasite balance was only established after that period.


Subject(s)
Cicatrix/pathology , Inflammation/immunology , Inflammation/pathology , Leishmaniasis, Cutaneous/pathology , Adolescent , Adult , Aged , Animals , Cicatrix/parasitology , Female , Humans , Immunity, Cellular , Immunohistochemistry , Leishmaniasis, Cutaneous/parasitology , Male , Microscopy , Middle Aged , Time Factors , Young Adult
16.
Multivariate Behav Res ; 45(1): 135-52, 2010 Jan 29.
Article in English | MEDLINE | ID: mdl-26789087

ABSTRACT

Connections between graphical Gaussian models and classical single-factor models are obtained by parameterizing the single-factor model as a graphical Gaussian model. Models are represented by independence graphs, and associations between each manifest variable and the latent factor are measured by factor partial correlations. Power calculations for the single-factor graphical Gaussian model are facilitated by expressing the manifest partial correlations as functions of the factor partial correlations. The power of selecting a graphical Gaussian model with an association structure between manifest variables compatible with a single-factor model is investigated. The results are illustrated using 2 examples: the 1st is a hypothetical factor model with parallel measures. The 2nd uses data from the British Household Panel Survey on job satisfaction.

17.
Appl Radiat Isot ; 67(10): 1769-74, 2009 Oct.
Article in English | MEDLINE | ID: mdl-19525118

ABSTRACT

In recent years, specially designed patches containing beta emitters have been developed for contact brachytherapy of skin lesions. The aim of the present work was to evaluate the biological effects of the (32)P-patch on the skin of Sencar mice as a result of a brachytherapy treatment. For this purpose, a (32)P-patch was prepared with Chromic (32)P-phosphate and silicone and the classical model of two-stage skin carcinogenesis was reproduced in Sencar mice. Animals were divided in six groups. Four groups received the contact brachytherapy treatments using a scheme of a single session of 40 and 60Gy (SD40 and SD60) and a scheme of two sessions of 40 and 60Gy each (FD40 and FD60). The other two groups were used as controls of the single (CSD) and the fractionated (CFD) treatments. Radiation doses were estimated with equations derived from the MIRD DOSE scheme, and biologically effective doses (BED) were calculated according to equations derived from the linear-quadratic model. The endpoint to evaluate the treatments effects was tumor size after a follow-up period of 44 days. Finally, animals were sacrificed in order to get samples of all tumors for histological analysis and PCNA staining. Erythema, dermatitis and skin ulceration developed in almost all treated animals, but they gradually healed with regeneration of tissue during the follow-up period. Radiation effects on the skin of SD40, SD60, FD40 and FD60 showed a significant reduction of the tumor size with regard to controls, independently of the scheme and the radiation dose considered. PCNA staining scores of control groups were higher than for treated groups, independently of the scheme and the radiation dose considered. This radioactive (32)P-silicone-patch which is easy to prepare and use in the treatment of skin diseases, seems promising as a radioactive device for clinical use.


Subject(s)
Brachytherapy/methods , Phosphorus Radioisotopes/therapeutic use , Skin Neoplasms/radiotherapy , Skin/radiation effects , Administration, Cutaneous , Animals , Female , Mice , Mice, Inbred SENCAR , Proliferating Cell Nuclear Antigen/metabolism , Radiotherapy Dosage , Skin Neoplasms/metabolism
18.
Br J Health Psychol ; 14(Pt 4): 681-99, 2009 Nov.
Article in English | MEDLINE | ID: mdl-19288976

ABSTRACT

OBJECTIVES: Theory and research suggest that the intention to smoke is the main determinant of smoking initiation and emphasizes the role of cognitive and social factors on the prediction of the intention to smoke. However, extended models such as the I-Change and results from published studies reveal inconsistencies regarding the impact of social influence on the intention to smoke. Possible explanations for this may be the definition and measurement of the constructs that have been used. DESIGN AND METHODS: The current study was designed with two main goals: (i) to test a measurement model for social influence, combining different types of social influence (subjective norms, perceived behaviour, and direct pressure) with various referents of influence (parents, siblings, peers, and teachers); (ii) to investigate the impact of social influence on adolescent intention to smoke, controlling for smoking behaviour. LISREL was used to test these models. The sample includes 3,064 Portuguese adolescents, with a mean age of 13.5 years, at the beginning of the seventh school grade. RESULTS: The hypothesized measurement model of social influence was supported by results and explained 29% of the variance of the intention to smoke. A more extended model, including attitude and self-efficacy, explained 55% of the variance of the intention to smoke. Perceived behaviour of peers, parental norms, and perceived behaviour of parents were the social influence factors with impact on adolescent intention to smoke. CONCLUSIONS: Results suggest that different referents exert their influence through distinct types of social influence and recommend further work on the definition and measurement of social influence.


Subject(s)
Intention , Smoking/psychology , Social Control, Informal , Adolescent , Adolescent Behavior , Female , Humans , Male , Portugal , Surveys and Questionnaires
19.
Exp Parasitol ; 121(4): 317-22, 2009 Apr.
Article in English | MEDLINE | ID: mdl-19135053

ABSTRACT

Analyses of MLEE, RAPD and LSSP-PCR were used to compare the panel of american tegumentary leishmaniasis (ATL) isolates obtained from lesions of patients with rare clinical manifestations of the disease and typical lesions. All of the 34 samples analyzed by MLEE demonstrated similar electromorphic profiles with Leishmania (Viannia) braziliensis reference strain. Through the RAPD analysis, nine genetic profiles (genotypes) were identified. LSSP-PCR corroborates the initial screening and phenetic analysis has grouped the isolates into two major clusters comprising the nine different genotypes. Prevalent genotype defined as LbmtDNAgen1 was detected in the largest number of isolates. There was no association between genotypes and clinical symptoms. However, two different genotypes could be identified in the initial (LbmtDNAGen9) and reactivated lesion (LbmtDNAGen3) of the same patient. Our results support the idea of a less pronounced genotypic diversity among L. (V.) braziliensis circulating in the State of Rio de Janeiro and demonstrate the useful application of these molecular markers in genetics variability studies.


Subject(s)
Genetic Variation , Leishmania braziliensis/classification , Leishmaniasis, Cutaneous/parasitology , Animals , Brazil , Cluster Analysis , DNA, Protozoan/analysis , Electrophoresis/methods , Enzymes/analysis , Female , Genetic Markers , Genotype , Humans , Leishmania braziliensis/enzymology , Leishmania braziliensis/genetics , Leishmaniasis, Mucocutaneous/parasitology , Male , Phylogeny , Polymerase Chain Reaction/methods , Random Amplified Polymorphic DNA Technique
20.
Biol Trace Elem Res ; 127(2): 143-7, 2009 Feb.
Article in English | MEDLINE | ID: mdl-18802669

ABSTRACT

The purpose of the present work was to evaluate the iron bioavailability of a new ferric pyrophosphate salt stabilized and solubilized with glycine. The prophylactic-preventive test in rats, using ferrous sulfate as the reference standard, was applied as the evaluating methodology both using water and yogurt as vehicles. Fifty female Sprague-Dawley rats weaned were randomized into five different groups (group 1: FeSO(4); group 2: pyr; group 3: FeSO(4) + yogurt; group 4: pyr + yogurt and group 5: control). The iron bioavailability (BioFe) of each compound was calculated using the formula proposed by Dutra-de-Oliveira et al. where BioFe % = (HbFef - HbFei) x 100/ToFeIn. Finally, the iron bioavailability results of each iron source were also given as relative biological value (RBV) using ferrous sulfate as the reference standard. The results showed that both BioFe % and RBV % of the new iron source tested is similar to that of the reference standard independently of the vehicle employed for the fortification procedure (FeSO(4) 49.46 +/- 12.0% and 100%; Pyr 52.66 +/- 15.02% and 106%; FeSO(4) + yogurth 54.39 +/- 13.92% and 110%; Pyr + yogurt 61.97 +/- 13.54% and 125%; Control 25.30 +/- 6.60, p < 0.05). Therefore, the stabilized and soluble ferric pyrophosphate may be considered as an optimal iron source for food fortification.


Subject(s)
Diphosphates/chemistry , Food, Fortified , Iron, Dietary/pharmacokinetics , Iron/chemistry , Analysis of Variance , Animals , Biological Availability , Diet , Diphosphates/pharmacokinetics , Female , Ferrous Compounds/chemistry , Ferrous Compounds/pharmacokinetics , Iron/pharmacokinetics , Random Allocation , Rats , Rats, Sprague-Dawley , Reference Standards , Solubility , Water , Yogurt
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