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1.
Sci Total Environ ; 671: 452-465, 2019 Jun 25.
Artículo en Inglés | MEDLINE | ID: mdl-30933801

RESUMEN

We quantify main ecosystem services (i.e. the contribution of ecosystems to human well-being) provided by rivers, lakes, coastal waters and connected ecosystems (riparian areas and floodplains) in Europe, including water provisioning, water purification, erosion prevention, flood protection, coastal protection, and recreation. We show European maps of ecosystem service capacity, flow (actual use), sustainability and efficiency. Then we explore the relationship between the services and the ecosystem condition at the European scale, considering the ecological status of aquatic ecosystems, reported under the EU Water Framework Directive, as a measure of the ecosystem integrity and biodiversity. Our results indicate that a higher delivery of the regulating and cultural ecosystem services analysed is mostly correlated with better conditions of aquatic ecosystems. Conversely, the use of provisioning services can result in pressures on the ecosystem. This suggests the importance of maintaining good ecological condition of aquatic ecosystems to ensure the delivery of ecosystem services in the future. These results at the continental scale, although limited to the ecosystem services under analysis, might be relevant to consider when investing in the protection and restoration of aquatic ecosystems called for by the current EU water policy and Biodiversity Strategy and by the United Nations Sustainable Development Goals.

2.
Lupus ; 28(2): 249-252, 2019 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-30616452

RESUMEN

Childhood-onset systemic lupus erythematosus (cSLE) is a chronic inflammatory multisystem autoimmune disease that requires multiple differential diagnoses. Munchausen by proxy syndrome (MBPS) is a form of child abuse, where a caregiver intentionally creates a medical history and induces or fabricates signs or disease in a patient. To our knowledge, there is no case report of MBPS mimicking cSLE diagnosis. We reported herein a 9-year-old male patient, with a history of multiple hospitalizations due to seizures with altered levels of consciousness. The mother reported malar rash, photosensitivity, alopecia, arthralgia, arterial hypertension, macroscopic hematuria, seizure and positive antinuclear antibodies. In the other service, he was treated with intravenous methylprednisolone, prednisone and mycophenolate mofetil. At 8 years and 8 months, he was admitted to our tertiary center with history of fever and macroscopic hematuria. Laboratory examinations were normal, including negative for antinuclear antibodies, anti-double stranded DNA, anticardiolipin, anti-Ro/SSA, anti-La/SSB, anti-RNP and anti-Sm antibodies. Multiple urine cultures revealed the presence of Enterococcus faecium, Acinetobacter sp., Stenotrophomonas maltophilia and Serratia marcescens, without any association with pyuria. At 8 years and 9 months, he was readmitted at emergency room with history of severe fever, headache, vomiting, photophobia, phonophobia and dizziness. The physical examination showed agitation, confusion, ataxic gait, slurred speech, horizontal nystagmus, painful facial expressions, tachycardia and weight loss. Brain magnetic resonance angiography and cerebrospinal fluid analysis were normal. During hospitalization, he had an acute episode of epistaxis and otalgia with excoriation in the auditory canal. At that moment, the suspicion of MBPS mimicking cSLE was raised and phenytoin intoxication was confirmed (peak phenytoin concentration was 45.4 mcg/mL, therapeutic range 10-20 mcg/mL). The mother and the patient were immediately separated, and she was replaced by another legal guardian. One week later, the neurological and other signs and symptoms were completely resolved. The child was placed under paternal custody with a court order and moved to another state. After that, the mother reported phenytoin use for her child and was referred to psychiatric follow-up. In conclusion, the first case of MBPS mimicking cSLE, resulting in multiple unnecessary examinations and treatments with delayed diagnosis was reported.


Asunto(s)
Síndrome de Munchausen Causado por Tercero/diagnóstico , Edad de Inicio , Niño , Diagnóstico Tardío , Diagnóstico Diferencial , Humanos , Lupus Eritematoso Sistémico/diagnóstico , Masculino , Procedimientos Innecesarios
3.
J Viral Hepat ; 25(11): 1244-1250, 2018 11.
Artículo en Inglés | MEDLINE | ID: mdl-29768686

RESUMEN

A novel controlled attenuation parameter (CAP) using FibroScan® has been developed for assessment of liver steatosis. The aim was to evaluate the frequency and associated factors for moderate/severe steatosis evaluated by CAP in CHC patients submitted to transient elastography (TE) by FibroScan® . CHC patients underwent TE with CAP evaluation. The classification of steatosis was defined as: CAP < 222 dB/m  =  S0; CAP ≥ 222 dB/m and <233dB/m  =  S1; ≥233 dB/m < 290dB/m  =  S2 and >= 290 dB/m  =  S3. The prevalence of moderate/severe steatosis (CAP ≥ S2) and the related independent factors were identified by a logistic regression analysis. A significance level of 5% was adopted. 1104 CHC patients, 85% genotype-1 were included (mean age 55 ± 11 years; 46% male, mean BMI 25 ± 4 Kg/m2 ). Systemic arterial hypertension and type 2 diabetes mellitus prevalences were 39% and 17%, respectively. Liver stiffness measurement ≥ 9.5 kPa was observed in 39% of patients and steatosis was identified in 50% (S1 = 7%, S2 = 28% and S3 = 15%). The variables independently associated with moderate/severe steatosis were: male gender (OR=1.35; P = .037; 95% CI:1.01-1.81); systemic arterial hypertension (OR=1.57; P = .002; 95% CI:1.17-2.10) and BMI (OR=1.17; P < .01;95% CI:1.12-1.22). In conclusion, when CAP was adopted as a tool to detect steatosis, genotype 1 CHC patients presented a high prevalence of moderate/advanced steatosis. In these patients, liver steatosis was associated mostly to metabolic factors (arterial hypertension and high BMI).


Asunto(s)
Diagnóstico por Imagen de Elasticidad , Hepatitis C Crónica/diagnóstico por imagen , Hepatitis C Crónica/epidemiología , Enfermedad del Hígado Graso no Alcohólico/diagnóstico por imagen , Enfermedad del Hígado Graso no Alcohólico/epidemiología , Adulto , Anciano , Brasil/epidemiología , Estudios Transversales , Femenino , Hepatitis C Crónica/patología , Hepatitis C Crónica/fisiopatología , Humanos , Hígado/diagnóstico por imagen , Hígado/patología , Masculino , Persona de Mediana Edad , Enfermedad del Hígado Graso no Alcohólico/patología , Enfermedad del Hígado Graso no Alcohólico/fisiopatología , Valor Predictivo de las Pruebas , Prevalencia , Estudios Retrospectivos , Factores de Riesgo
4.
Aliment Pharmacol Ther ; 47(7): 989-1000, 2018 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-29446106

RESUMEN

BACKGROUND: Liver fibrosis is often accompanied by steatosis, particularly in patients with non-alcoholic fatty liver disease (NAFLD), and its non-invasive characterisation is of utmost importance. Vibration-controlled transient elastography is the non-invasive method of choice; however, recent research suggests that steatosis may influence its diagnostic performance. Controlled Attenuation Parameter (CAP) added to transient elastography enables simultaneous assessment of steatosis and fibrosis. AIM: To determine how to use CAP in interpreting liver stiffness measurements. METHODS: This is a secondary analysis of data from an individual patient data meta-analysis on CAP. The main exclusion criteria for the current analysis were unknown aetiology, unreliable elastography measurement and data already used for the same research question. Aetiology-specific liver stiffness measurement cut-offs were determined and used to estimate positive and negative predictive values (PPV/NPV) with logistic regression as functions of CAP. RESULTS: Two thousand and fifty eight patients fulfilled the inclusion criteria (37% women, 18% NAFLD/NASH, 42% HBV, 40% HCV, 51% significant fibrosis ≥ F2). Youden optimised cut-offs were only sufficient for ruling out cirrhosis (NPV of 98%). With sensitivity and specificity-optimised cut-offs, NPV for ruling out significant fibrosis was moderate (70%) and could be improved slightly through consideration of CAP. PPV for significant fibrosis and cirrhosis were 68% and 55% respectively, despite specificity-optimised cut-offs for cirrhosis. CONCLUSIONS: Liver stiffness measurement values below aetiology-specific cut-offs are very useful for ruling out cirrhosis, and to a lesser extent for ruling out significant fibrosis. In the case of the latter, Controlled Attenuation Parameter can improve interpretation slightly. Even if cut-offs are very high, liver stiffness measurements are not very reliable for ruling in fibrosis or cirrhosis.


Asunto(s)
Diagnóstico por Imagen de Elasticidad/métodos , Cirrosis Hepática/diagnóstico , Hígado/diagnóstico por imagen , Adulto , Biopsia , Elasticidad , Femenino , Humanos , Hígado/patología , Cirrosis Hepática/patología , Cirrosis Hepática/fisiopatología , Pruebas de Función Hepática/métodos , Pruebas de Función Hepática/normas , Masculino , Persona de Mediana Edad , Enfermedad del Hígado Graso no Alcohólico/diagnóstico , Enfermedad del Hígado Graso no Alcohólico/patología , Estudios Retrospectivos , Sensibilidad y Especificidad
5.
Int J Cosmet Sci ; 38(5): 481-6, 2016 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-26919038

RESUMEN

OBJECTIVES: The aim of this study was to evaluate by central composite design the influence of colouring agents in lipstick colour, expressed by L*, a*, b* parameters (CIELab system) where L* indicates lightness, and a* and b* are the chromaticity coordinates. The a* indicates colour direction from red to green and b* from yellow to blue. METHODS: Lipsticks were formulated as described by (Recent Adv. Prosp. Potent Med. Plants, 2009 and 39). The combined effect of three variables (dye, pigment and opacifier) was evaluated by different formulations in a central composite design. Colour parameters (L*, a*, b*) were analysed by reflectance spectrophotometry. Lipsticks were characterized by visual analyses and melting point. RESULTS: All formulations were integrate and homogeneous. The pigments and dye do not influence in colour transfer neither in melting point of lipsticks. On the other hand, results indicated that variables studied show influence only in parameter b*, whereas for L* and a* values there was no significant difference (P < 0.05). CONCLUSION: It was possible to verify that only the colour parameter b* was influenced by the variation in colouring agent's concentrations in lipstick formulation, leading to the production of the colour ranging between violet and light red. Such results are useful for developing new lipstick formulations to obtain the desired colour in the final product.


Asunto(s)
Colorantes , Cosméticos , Colorimetría/instrumentación
7.
J Viral Hepat ; 19(4): 244-53, 2012 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-22404722

RESUMEN

A novel controlled attenuation parameter (CAP) has been developed for Fibroscan(®) to assess liver steatosis, simultaneously with liver stiffness measurement (LSM). We assessed CAP diagnostic accuracy in a large cohort of patients with chronic hepatitis C (CHC) virus. A total of 615 patients with CHC, who underwent both Fibroscan(®) and liver biopsy, were analysed. Fibrosis was graded using METAVIR score. Steatosis was categorized by visual assessment as S(0) : steatosis in <10% of hepatocytes, S(1) : 11-33%, S(2) : 34-66% and S(3) : 67-100%. Performances of CAP and liver stiffness were determined using receiver operating characteristic (ROC) curve analysis and cross-validated using the bootstrap method. The Obuchowski measure was used to assess overall accuracy of CAP and to differentiate between steatosis grades. In multivariate analysis, CAP was related to steatosis (P < 10(-15) ) independently of fibrosis stage (which was related to LSM). The areas under ROC curves using CAP to detect steatosis were 0.80 (95% CI, 0.75-0.84) for S ≥ S(1) , 0.86 (0.81-0.92) for S ≥ S(2) and 0.88 (0.73-1) S = S(3) . CAP exhibited a good ability to differentiate steatosis grades (Obuchowski measure = 0.92). Performance of LSM for fibrosis assessment confirmed results from previous studies. CAP is a novel tool to assess the degree of steatosis and both fibrosis and steatosis can be evaluated noninvasively during the same procedure using Fibroscan(®) , in patients with CHC.


Asunto(s)
Técnicas de Laboratorio Clínico/métodos , Hígado Graso/diagnóstico , Hígado Graso/patología , Hepatitis C Crónica/complicaciones , Hepatitis C Crónica/patología , Adulto , Biopsia , Diagnóstico por Imagen de Elasticidad , Femenino , Humanos , Hígado/patología , Masculino , Persona de Mediana Edad , Curva ROC , Índice de Severidad de la Enfermedad
8.
Gut ; 58(12): 1662-9, 2009 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-19671541

RESUMEN

BACKGROUND AND AIMS: Hepatitis C virus (HCV) genotype 4 (HCV-4) is increasing in prevalence in Western countries. However, little is known about the severity of the disease and response to treatment. The aim of this study was to assess the predictors (logistic regression) of severe fibrosis (METAVIR score F3-F4), and sustained virological response (SVR) to peginterferon and ribavirin in 226 consecutive HCV-4 patients (Egyptians 40%, Europeans 35% and Africans 24%). PATIENTS AND METHODS: Insulin resistance was assessed using the homeostasis model (HOMA-IR). Serum HCV-RNA level (bDNA) and subtypes of HCV (LiPA) were determined for all patients. RESULTS: Insulin resistance (HOMA-IR >3) was present in 105 patients (46%), and was associated with: age >45 years (OR, 2.614; 95% CI, 1.316 to 5.194), body mass index (BMI) >25 kg/m(2) (OR, 2.105; 95% CI, 1.048 to 4.229), serum HCV-RNA >800 000 IU/ml (OR, 3.143; 95% CI, 1.503 to 6.574), severe fibrosis (OR, 2.657; 95% CI, 1.214 to 5.818), and steatosis >30% (OR, 2.488; 95% CI, 1.105 to 5.602). Severe fibrosis was present in 67 patients (29%) and was associated with Egyptian origin (OR, 5.872; 95% CI, 2.747 to 12.553), excessive alcohol intake (OR, 5.311; 95% CI, 1.287 to 21.924), and HOMA-IR >3 (OR, 3.864; 95% CI, 1.859 to 8.034). 108 patients received a 48 week course of peginterferon plus ribavirin. SVR (undetectable serum HCV-RNA (TMA) 24 weeks after treatment stopping) was achieved in 59 patients (55%) and was associated with Egyptian origin (OR, 13.119; 95% CI, 3.089 to 55.706), HOMA-IR <2 (OR, 5.314; 95% CI, 1.953 to 14.459), and non-severe fibrosis (OR, 8.059; 95% CI, 2.512 to 25.855). CONCLUSION: Insulin resistance and geographical origin are major predictors of liver fibrosis and response to peginterferon and ribavirin in HCV-4 patients. Insulin resistance is frequently encountered in these patients, and correlated independently with serum HCV-RNA.


Asunto(s)
Antivirales/uso terapéutico , Hepatitis C Crónica/complicaciones , Resistencia a la Insulina/etnología , Cirrosis Hepática/virología , Adulto , Población Negra/estadística & datos numéricos , Egipto/etnología , Femenino , Francia/epidemiología , Hepacivirus/clasificación , Hepacivirus/aislamiento & purificación , Hepatitis C Crónica/tratamiento farmacológico , Hepatitis C Crónica/etnología , Hepatitis C Crónica/virología , Humanos , Interferón alfa-2 , Interferón-alfa/uso terapéutico , Cirrosis Hepática/etnología , Cirrosis Hepática/fisiopatología , Masculino , Persona de Mediana Edad , Polietilenglicoles/uso terapéutico , Estudios Prospectivos , ARN Viral/sangre , Proteínas Recombinantes , Ribavirina/uso terapéutico , Resultado del Tratamiento
9.
Mar Environ Res ; 60(5): 594-628, 2005 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-15996728

RESUMEN

Ria de Aveiro is a very important area of the Portuguese coast, which has been under an increasing anthropogenic pressure for several decades and, contributes to the degradation of the lagoon's water quality. This work presents both a characterisation of the water quality of the Ria de Aveiro lagoon, using physical, chemical and biological experimental data, and an implementation of a numerical model for the water quality of the lagoon. The ultimate goal is to obtain an accurate numerical model able to simulate major water quality features of the lagoon under the influence of different forcing conditions. Data analysis reveals good correlations between the salinity and almost all the water quality variables as well as between the different variables. The maximum biochemical oxygen demand concentration (BOD) depends on the light intensity, the temperature and the river inputs. The main vulnerable areas of the lagoon, from the water quality point of view, seem to be the far end of the main channels, where low dissolved oxygen concentration (DO) and high BOD concentrations are observed. The numerical model of the Ria de Aveiro has reproduced both winter-spring and spring-summer events related to the lagoon water quality as well as its main pattern. Both data and modelling results show that the BOD5 concentrations (where the subscript '5' means that the BOD measurements were conducted for five days, without inhibitor of nitrification) are driven by the river influence, during the winter-spring period, and by the biological activity during the spring-summer period. The DO concentrations show high values in the spring-summer period and smaller concentrations in the winter-spring period at the far end of the lagoon. The application of the model to the study of scenarios has demonstrated the role of nutrients and light in the phytoplankton growth, the relationship between DO and phytoplankton concentrations, as well as the effect of the BOD degradation in the ammonia (NH4) regeneration.


Asunto(s)
Modelos Teóricos , Contaminantes del Agua/análisis , Monitoreo del Ambiente , Oxígeno/metabolismo , Portugal , Control de Calidad , Reproducibilidad de los Resultados , Ríos , Estaciones del Año , Movimientos del Agua
10.
Water Sci Technol ; 49(7): 169-77, 2004.
Artículo en Inglés | MEDLINE | ID: mdl-15195435

RESUMEN

The Water Framework Directive (WFD) is a new legislative framework to manage, use, protect, and restore surface water and groundwater resources and coastal waters in the European Union (EU). The aim is to ensure sustainable water management and to reach good water quality by 2015. The assessment of the ecological status and setting of the practical management goals require several steps. The process has started with the characterisation of the river basins including identification of surface water bodies and types, and identification of significant anthropogenic pressures and impacts. The water bodies will be classified in five quality classes (high, good, moderate, poor, bad) based on the Ecological Quality Ratio, which is a ratio between reference conditions and measured status of the biological quality elements. The normative criteria for high, good and moderate ecological status described in the WFD need to be made operational because those will be used to set the practical quality targets for surface water management. National ecological assessment systems and classifications will be harmonised through the WFD intercalibration exercise in order to ensure an equal level of ambition in achieving good surface waters status all over Europe.


Asunto(s)
Ecología , Contaminación del Agua/prevención & control , Abastecimiento de Agua/normas , Calibración , Monitoreo del Ambiente , Europa (Continente) , Valores de Referencia
11.
Arq Neuropsiquiatr ; 59(3-B): 676-80, 2001 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-11593263

RESUMEN

OBJECTIVE: Clinical and surgical outcome of patients with subarachnoid hemorrhage (SAH) due to ruptured aneurysm were assessed in comparison to pre-operative data and risk factors such as previous medical history, clinical presenting condition, CT findings and site of bleeding. METHODS: We evaluated 100 consecutive patients with aneurysmal SAH. Gender, color, history of hypertension, smoking habit, site and size of aneurysm, admittance and before surgery Hunt Hess scale, need for cerebro-spinal fluid shunt, presence of complications during the surgical procedure, Glasgow Outcome Scale, presence of vasospasm and of rebleeding were assessed and these data matched to outcome. For statistical analysis, we applied the chi-squared test or Fisher's test using the pondered kappa coefficient. Kruskal-Wallis test was used for comparison of continue variables. Tendency of proportion was analyzed through Cochran-Armitage test. Significance level adopted was 5%. RESULTS: Patients studied were mainly white, female, without previous history of hypertension and non-smokers. Upon hospital admittance, grade 2 of Hunt-Hess scale was most frequently observed (34%), while grade 3 of Fisher scale was the most prevalent. Single aneurysms were most frequent at anterior circulation, between 12 and 24 mm. The most frequent Glasgow Outcome Scale observed was 5 (60%). Hunt Hess upon the moment of surgery and presence of complications during surgical procedure showed positive correlation with clinical outcome (p=0.00002 and p=0.001, respectively). Other variables were not significantly correlated to prognosis. Tendency of proportion was observed between Hunt-Hess scale and Fisher scale. CONCLUSION: Among variables such as epidemiological data, previous medical history and presenting conditions of patients with ruptured aneurysms, the Hunt-Hess scale upon the moment of surgery and the presence of surgical adversities are statistically related to degree of disability.


Asunto(s)
Hemorragia Subaracnoidea/cirugía , Brasil/epidemiología , Femenino , Escala de Coma de Glasgow , Humanos , Aneurisma Intracraneal/epidemiología , Aneurisma Intracraneal/cirugía , Masculino , Persona de Mediana Edad , Complicaciones Posoperatorias , Cuidados Preoperatorios , Estudios Prospectivos , Factores de Riesgo , Estadísticas no Paramétricas , Hemorragia Subaracnoidea/epidemiología , Resultado del Tratamiento
12.
Sci Total Environ ; 268(1-3): 31-45, 2001 Mar 14.
Artículo en Inglés | MEDLINE | ID: mdl-11315745

RESUMEN

The aim of the present study was the evaluation of methods for estimating the content of bio-physical parameters in lake water on the basis of spectral reflectance measured above water surface, in particular the estimation of chlorophyll-a (chl-a) concentrations. Data sets considered refer to some sampling point located in the sub-alpine meso-eutrophic Lake Iseo, surveyed six times over the period March-July and once in November 1998, as these months were very important for the characterization of the springtime algal bloom, which affect the lake waters yearly. At each point station, limnological observations (chlorophyll, total suspended solids, Secchi disk depth) were conducted simultaneously with optical measurements. The latter consisted of water leaving radiance measured by means of a spectroradiometer above the water surface; moreover, a standard reflector radiance was also measured to obtain the water reflectance. Reflectance spectra were transformed according to two well-documented models and correlated to water quality parameters, to investigate their performances as retrieval algorithms under different conditions and referring to different analytical methods. Results outline the sensitivity of the models to chl-a concentrations, different phytoplankton composition, and the sampling depth.


Asunto(s)
Clorofila/análisis , Monitoreo del Ambiente/métodos , Fitoplancton , Nave Espacial , Clorofila A , Simulación por Computador , Óptica y Fotónica , Agua , Contaminantes del Agua/análisis
13.
Spine (Phila Pa 1976) ; 25(2): 260-4, 2000 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-10685492

RESUMEN

STUDY DESIGN: Four cadavers had cervical foraminotomies performed at noncontiguous levels using either the standard open technique or the microendoscopic technique. OBJECTIVES: To evaluate the feasibility of using a minimally invasive technique for posterior decompression of cervical disc disease. SUMMARY OF BACKGROUND DATA: Even though the anterior approach is more commonly performed for the treatment of cervical disc disease, the posterior approach has distinct advantages in selected cases of foraminal stenosis and posterolateral disc herniation. Current technique, however, requires extensive muscle dissection, and is, therefore, subject to significant morbidity. METHODS: Each of four cadavers had posterior cervical foraminotomies performed using either the MICROENDOSCOPIC (MED) technique, or the standard open technique. Three noncontiguous levels were decompressed using one technique, and the other technique was used for the adjacent contralateral decompression. Each specimen was then evaluated with postoperative myelogram/CT and open dissection. Laminotomy size, length of root decompressed, and percentage of facet removed were measured. RESULTS: Average vertical diameter decompression and percentage of facet removed were significantly greater for the MED technique than for the open technique. Transverse diameter of the laminotomy area and the average length of decompressed root were not significantly different between the techniques. CONCLUSION: Posterior cervical foraminotomy, using the microendoscopic technique, is technically feasible and may be applicable to the treatment of foraminal stenosis and laterally located cervical disc herniation. Studies in live animals are currently examining techniques for hemostasis.


Asunto(s)
Vértebras Cervicales/cirugía , Discectomía/métodos , Endoscopía/métodos , Disco Intervertebral/cirugía , Compresión de la Médula Espinal/cirugía , Anciano , Estudios de Factibilidad , Humanos , Persona de Mediana Edad
14.
Pract Periodontics Aesthet Dent ; 12(2): 223-8; quiz 230, 2000 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-11404963

RESUMEN

Lesions that result from dental erosion can be difficult to recognize--particularly when abrasion and attrition are also present. Consequently, dental erosion is often misdiagnosed and mistreated by radical restorative modalities that compromise the vitality of the pulp. This article provides clinicians with knowledge concerning the diagnosis of the complex lesions of dental wear and demonstrates the conservative treatment of this condition. Two cases that exhibit marked tooth wear in anterior teeth and their subsequent restoration utilizing occlusal principles and composite resin are presented.


Asunto(s)
Restauración Dental Permanente/métodos , Erosión de los Dientes/diagnóstico , Grabado Ácido Dental , Adulto , Bebidas/efectos adversos , Bruxismo/complicaciones , Relación Céntrica , Niño , Resinas Compuestas , Recubrimientos Dentinarios , Diagnóstico Diferencial , Humanos , Incisivo , Masculino , Ajuste Oclusal , Abrasión de los Dientes/diagnóstico , Atrición Dental/diagnóstico , Erosión de los Dientes/terapia , Vino/efectos adversos
15.
Neurosurgery ; 45(3): 549-91; discussion 591-2, 1999 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-10493377

RESUMEN

OBJECTIVE: We review the anatomy of the mesial temporal lobe region, establishing the relationships among the intraventricular, extraventricular, and surrounding vascular structures and their angiographic characterization. We also demonstrate the clinical application of these anatomic landmarks in an anatomic temporal lobectomy plus amygdalohippocampectomy. METHODS: Fifty-two adult cadaveric hemispheres and 12 adult cadaveric heads were studied, using a magnification ranging from 3x to 40x, after perfusion of the arteries and veins with colored latex. RESULTS: The intraventricular elements are the hippocampus, fimbria, amygdala, and choroidal fissure; the extraventricular elements are the uncus and parahippocampal and dentate gyri. The uncus has an anterior segment, an apex, and a posterior segment that has an inferior and a posteromedial surface; the uncus is related medially to cisternal elements and laterally to intraventricular elements. The anterior segment is related to the proximal sylvian fissure, internal carotid artery, proximal M1 segment of the middle cerebral artery, proximal cisternal anterior choroidal artery, and amygdala. The apex is related to the oculomotor nerve, uncal recess, and amygdala; the posteromedial surface is related to the P2A segment of the posterior cerebral artery inferiorly, to the distal cisternal anterior choroidal artery superiorly, and to the head of the hippocampus and amygdala intraventricularly. The choroidal fissure is located between the thalamus and fimbria; it begins at the inferior choroidal point behind the head of the hippocampus and constitutes the medial wall of the posterior two-thirds of the temporal horn. CONCLUSION: Not only is the knowledge of these relations useful to angiographically characterize the mesial temporal region, but it has also proven to be of extreme value during microsurgeries involving this region.


Asunto(s)
Amígdala del Cerebelo/anatomía & histología , Amígdala del Cerebelo/cirugía , Arterias Cerebrales/anatomía & histología , Venas Cerebrales/anatomía & histología , Hipocampo/anatomía & histología , Hipocampo/cirugía , Lóbulo Temporal/anatomía & histología , Lóbulo Temporal/cirugía , Adulto , Amígdala del Cerebelo/irrigación sanguínea , Amígdala del Cerebelo/diagnóstico por imagen , Encéfalo/anatomía & histología , Encéfalo/cirugía , Cadáver , Hipocampo/irrigación sanguínea , Hipocampo/diagnóstico por imagen , Humanos , Microcirugia , Procedimientos Neuroquirúrgicos , Radiografía , Lóbulo Temporal/irrigación sanguínea , Lóbulo Temporal/diagnóstico por imagen
16.
J Prosthet Dent ; 82(3): 312-6, 1999 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-10479258

RESUMEN

STATEMENT OF THE PROBLEM: Gold screw loosening is a frequent problem that affects dental implants. PURPOSE: This study determined the effect of spring washers on gold screw displacements during applied removal torque in dental implants. MATERIAL AND METHODS: A 3-unit fixed partial denture was cast in semiprecious alloy and fixed to 2 dental implants with gold-retaining screws. Implants were embedded in acrylic resin and restrained from movement. A miniature load sensor was attached to a torque controller handpiece to accurately measure the time and torque needed to completely loosen the gold screws. Rotational displacements were calculated for 4 experimental setups, involving washers placed on (a) both, (b) the mesial, (c) the distal, and (d) no implants. Screw displacement data were compared between implants in all 4 combinations by means of paired t tests. RESULTS: Gold screws with underlying conical spring washers underwent on average up to 35% (14.1 microm) more rotational displacement during applied removal torque than those without washers. CONCLUSION: Inclusion of a conical spring washer significantly increased the amount of rotational displacement needed to completely loosen an implant gold retaining screw.


Asunto(s)
Prótesis Dental de Soporte Implantado , Análisis del Estrés Dental , Retención de Dentadura/instrumentación , Aleaciones de Oro , Dentadura Parcial Fija , Humanos , Torque
17.
Int J Oral Maxillofac Implants ; 14(3): 337-41, 1999.
Artículo en Inglés | MEDLINE | ID: mdl-10379106

RESUMEN

Gold screw loosening is a problem that frequently affects dental implants. The application of a preload has been the main means of preventing loosening. However, this measure has not been able to eliminate its occurrence. In this study the effect of a washer in a Brånemark-type implant on the loosening conditions of the retaining screw was investigated using a finite element simulation. The simulation indicated that a washer may significantly increase the tolerance of a screw against loosening. This is accomplished by increasing the tolerance of the implant against deformation. The addition of a customized washer to a dental implant system may offer a very simple and inexpensive solution for the persistent problem of screw loosening.


Asunto(s)
Implantación Dental Endoósea/instrumentación , Implantes Dentales , Retención de Prótesis Dentales/instrumentación , Pilares Dentales , Pins Dentales , Análisis del Estrés Dental , Análisis de Elementos Finitos , Humanos , Análisis Numérico Asistido por Computador
18.
FEBS Lett ; 383(3): 277-83, 1996 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-8925913

RESUMEN

We report here the cloning and the characterization of the T. pyriformis CCT eta gene (TpCCT eta) and also a partial sequence of the corresponding T. thermophila gene (TtCCT eta). The TpCCt eta gene encodes a protein sharing a 60.3% identity with the mouse CCT eta. We have studied the expression of these genes in Tetrahymena exponentially growing cells, cells regenerating their cilia for different periods and during different stages of the cell sexual reproduction. These genes have similar patterns of expression to those of the previously identified TpCCt gamma gene. Indeed, the Tetrahymena CCT eta and CCT gamma genes are up-regulated at 60-120 min of cilia recovery, and in conjugation when vegetative growth was resumed and cell division took place. Our results seem to indicate that both CCT subunits play an important role in the biogenesis of the newly synthesized cilia of Tetrahymena and during its cell division.


Asunto(s)
Chaperoninas/biosíntesis , Regulación de la Expresión Génica , Genes Protozoarios , Proteínas Protozoarias , Tetrahymena pyriformis/fisiología , Secuencia de Aminoácidos , Animales , Secuencia de Bases , División Celular , Chaperonina con TCP-1 , Clonación Molecular , Cartilla de ADN , Sustancias Macromoleculares , Ratones , Datos de Secuencia Molecular , Proteínas Recombinantes/biosíntesis , Reproducción , Homología de Secuencia de Aminoácido , Tetrahymena pyriformis/genética , Tetrahymena pyriformis/metabolismo , Tetrahymena thermophila/genética , Tetrahymena thermophila/fisiología
19.
Caries Res ; 30(5): 373-8, 1996.
Artículo en Inglés | MEDLINE | ID: mdl-8877092

RESUMEN

The erosion caused in vitro by cola-type and guaraná-type beverages (the latter is a soft drink sold in Brazil), and a canned lemon juice on the enamel of human deciduous teeth was analyzed. Morphological analysis of affected enamel was done using stereomicroscopy and scanning electron microscopy (SEM). The harmful effect of all test products on deciduous enamel was clearly demonstrated. Stereomicroscopy showed loss of gloss and an alteration in normal color of enamel, with irregular loss of dental tissue in variable degrees. Such a loss became more serious as the time of incubation increased. Different degrees of solubilization of enamel prisms were demonstrated by SEM, affecting initially the sheaths and the heads of prisms and later their tails. Areas of erosion increased in proportion to the time of incubation. All the products showed a great erosive potential on human deciduous dental enamel.


Asunto(s)
Bebidas/efectos adversos , Erosión de los Dientes/patología , Diente Primario/patología , Preescolar , Citrus , Esmalte Dental/patología , Esmalte Dental/ultraestructura , Solubilidad del Esmalte Dental , Frutas , Humanos , Concentración de Iones de Hidrógeno , Microscopía/métodos , Microscopía Electrónica de Rastreo , Erosión de los Dientes/etiología
20.
Quintessence Int ; 25(12): 835-8, 1994 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-7568692

RESUMEN

A technique used to repair the abutment tooth of a fixed partial metal-ceramic prosthesis is described. This prosthesis extended from the maxillary central incisor to the left canine. The whole porcelain facial aspect of the central incisor had been fractured. Following a reduction of the metallic structure, a single porcelain crown was bonded to that area. The repair was quick, less expensive and less difficult than removal of the prosthesis and fabrication of a replacement, and provided excellent esthetic and functional results.


Asunto(s)
Pilares Dentales , Porcelana Dental , Reparación de Prótesis Dental , Dentadura Parcial Fija , Adulto , Coronas , Cementos de Ionómero Vítreo , Humanos , Masculino , Aleaciones de Cerámica y Metal
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