The Effect of Different Oxygen Surface Functionalization of Carbon Nanotubes on the Electrical Resistivity and Strain Sensing Function of Cement Pastes.

Different studies in the literature indicate the effectiveness of CNTs as reinforcing materials in cement-matrix composites due to their high mechanical strength. Nevertheless, their incorporation into cement presents some difficulties due to their tendency to agglomerate, yielding a non-homogeneous dispersion in the paste mix that results in a poor cement-CNTs interaction. This makes the surface modification of the CNTs by introducing functional groups on the surface necessary. In this study, three different treatments for incorporating polar oxygen functional groups onto the surface of carbon nanotubes have been carried out, with the objective of evaluating the influence of the type and oxidation degree on the mechanical and electrical properties and in strain-sensing function of cement pastes containing CNTs. One treatment is in liquid phase (surface oxidation with HNO3/H2SO4), the second is in gas phase (O3 treatment at 25 and 160 °C), and a third is a combination of gas-phase O3 treatment plus NaOH liquid phase. The electrical conductivity of cement pastes increased with O3- and O3-NaOH-treated CNTs with respect to non-treated ones. Furthermore, the oxygen functionalization treatments clearly improve the strain sensing performance of the CNT-cement pastes, particularly in terms of the accuracy of the linear correlation between the resistance and the stress, as well as the increase in the gage factor from 28 to 65. Additionally, the incorporation of either non-functionalized or functionalized CNTs did not produce any significant modification of the mechanical properties of CNTs. Therefore, the functionalization of CNTs favours the de-agglomeration of CNTs in the cement matrix and consequently, the electrical conductivity, without affecting the mechanical behaviour.

Chemical characterization of emissions from a municipal solid waste treatment plant.

Gaseous emissions are an important problem in municipal solid waste (MSW) treatment plants. The sources points of emissions considered in the present work are: fresh compost, mature compost, landfill leaks and leachate ponds. Hydrogen sulphide, ammonia and volatile organic compounds (VOCs) were analysed in the emissions from these sources. Hydrogen sulphide and ammonia were important contributors to the total emission volume. Landfill leaks are significant source points of emissions of H2S; the average concentration of H2S in biogas from the landfill leaks is around 1700 ppmv. The fresh composting site was also an important contributor of H2S to the total emission volume; its concentration varied between 3.2 and 1.7 ppmv and a decrease with time was observed. The mature composting site showed a reduction of H2S concentration (<0.1 ppmv). Leachate pond showed a low concentration of H2S (in order of ppbv). Regarding NH3, composting sites and landfill leaks are notable source points of emissions (composting sites varied around 30-600 ppmv; biogas from landfill leaks varied from 160 to 640 ppmv). Regarding VOCs, the main compounds were: limonene, p-cymene, pinene, cyclohexane, reaching concentrations around 0.2-4.3 ppmv. H2S/NH3, limonene/p-cymene, limonene/cyclohexane ratios can be useful for analysing and identifying the emission sources.

Reference values of thyroid volume in a healthy, non-iodine-deficient Spanish population.

Our aim was to assess reference values of thyroid volume by ultrasonography in healthy adult subjects. We conducted an epidemiological cross-sectional study where 880 subjects were randomly selected from the town census of L'Hospitalet de Llobregat after being invited to participate in our study directly by mail and phone call. We made a clinical history of each subject and determined serum thyrotropin, antiperoxidase antibodies, urinary iodine excretion and thyroid volume by ultrasonography. Subjects with thyroid disease were excluded. We finally studied 268 representative subjects. The reference thyroid volume was median 7.31 ml, mean 8.22 ml (Confidence Interval: 7.75 - 8.69 ml). In men: median 9.19 ml, mean 9.87 ml (CI: 9.09 - 10.65 ml); in women: median 6.19 ml, mean 6.57 ml (CI: 6.22 - 9.92 ml) (p < 0.0001). We grouped the subjects into decades, and found that thyroid volume was different (p = 0.0034) in males because the younger group had lower volume. We did not find any differences among age groups in women. The mean of the urinary iodine excretion was 154.23 microg/l. We have determined reference values of thyroid volume measured by ultrasonography in our iodine non-deficient population and prepared tables that distribute thyroid volume by sex and age.

[Early diabetic nephropathy and cardiovascular disease in a Mediterranean population: risk factors and treatment intensity]. / Nefropatía diabética inicial y enfermedad cardiovascular en una población mediterránea: factores de riesgo y grado de tratamiento.

The objective of this cross-sectional study was to evaluate the impact of early diabetic nephropathy on the presence of cardiovascular disease (CVD) in a Mediterranean population, as well as the prevalence in these patients of traditional cardiovascular risk factors and its treatment intensity in accordance with international recommendations. In 123 patients with type 2 diabetes and incipient nephropathy the presence of CVD, smoking, hypertension, dyslipemia, and their treatment was recorded. CVD prevalence was 34%. Age, nephropathy stage (micro/macroalbuminuria), and smoking were associated with the presence of CVD. Hypertension, dyslipemia, and smoking were present in 83%, 81%, and 59%, respectively. Coexistence of several risk factors was frequent and was associated with a higher incidence of CVD. 79% hypertensive patients and 43% dyslipemic patients received pharmacological treatment but only 17% and 9%, respectively, reached a good control of their disease. Patients with known CVD showed also a deficient control. Accordingly, early diabetic nephropathy induces a multiplier effect on the cardiovascular risk of a Mediterranean population. Higher prevalence and association with cardiovascular risk factors, with smoking in a predominant role, are associated with this higher risk. Despite this, the intensity of treatment and control of these risk factors is deficient, which means that a better and more intensive treatment should reduce the morbidity and mortality in these patients.

Ultrasonographic thyroid volume as a reliable prognostic index of radioiodine-131 treatment outcome in Graves' disease hyperthyroidism.

OBJECTIVE: We studied the relationship between thyroid volume, thyroid function and immunological markers of Graves' disease (GD) to determine prognostic factors of treatment response to low-dose radioiodine-131 (131I). MATERIAL AND METHODS: A prospective study of 40 patients with GD hyperthyroidism treated with 131I (141 +/- 85MBq) and 10 GD patients who went spontaneously into remission (controls). Free T4, total T3 and basal TSH levels, TSH-receptor antibodies (TRAb) and anti-thyroid peroxidase antibodies (TPOAb) were studied. Thyroid volume was determined by ultrasonography. Logistic regression models were used to predict the probability of final thyroid status. Receiver-operating characteristics (ROC) curves and Hosmer Lemeshow tests were used to evaluate the final statistical models. RESULTS: Of 40 patients treated with 131I, 16 became euthyroid, 12 hyperthyroid and 12 hypothyroid at 12 months. Median thyroid volume was reduced from 24.8 ml before to 8.5 ml at 12 months (p<0.001). In 10 control patients, the median reduction was from 16.6 ml to 11.3 ml (p=0.029). Thyroid volume reduction was lower in the hyperthyroid than in the euthyroid group, but higher in the hypothyroid group. Thyroid volume at baseline and at 3 months predicted hyperthyroidism outcome with a cut-off of 45 ml and 24.4 ml, respectively (odds ratio 1.074, p=0.003, ROC curve 0.78 and odds ratio 1.182, p=0.012, ROC curve 0.86 respectively). Thyroid volume at 6 months differentiated the hyperthyroid group with a cut-off of 17 ml. Thyroid volume at 3 and 6 months with a cut-off of 8.5 ml and 9.3 ml respectively, predicts permanent hypothyroidism outcome (odds ratio 0.768 and 0.685, p=0.012 and p=0.008, ROC curve 0.89 and 0.88, respectively). Changes in thyroid echogenicity and TRAb and TPOAb levels did not show any predictive value in the follow-up after 131I therapeutic outcome. CONCLUSION: The study shows that the ultrasonographic thyroid volume at 3 and 6 months after low-dose 131I treatment for GD hyperthyroidism could be a reliable prognostic factor of thyroid function outcome in the first year after treatment, and also reveals that the changes in the thyroid echogenicity and in the immunological markers of GD have no prognostic value.

[Anthropometry and the reference values of body composition by bioelectrical impedance in the adult population of L'Hospitalet de Llobregat]. / Antropometría y valores de referencia de la composición corporal por bioimpedanciometría en la población adulta de L'Hospitalet de Llobregat.

BACKGROUND: The aim of the present study was to assess the anthropometric variables and the reference values of body composition in the adult population of L'Hospitalet de Llobregat, due to the lack of epidemiological studies on this matter in Spain. PATIENTS AND METHODS: We studied 234 normal subjects, 134 males, mean age 41.4 years, and 134 females, mean age 40.7 years, selected from the census of L'Hospitalet de Llobregat and representative of its population in sex and age. We determined anthropometric characteristics, body weight, height, body mass index, waist-hip ratio and body composition parameters: total body water, free fat mass, fat mass and body fat by bioelectrical impedance analyzer. RESULTS: Twenty-four males and 33 females were obese, and out of them 2 males and 4 women presented morbid obesity. The body mass index was higher either in males (p = 0.017) or in females (p = 0. 0001) in the last decades in relation to first decade, and in women was as consequence of higher fat mass (p = 0.0001). The waist-hip ratio was 0.93 (0.08) in male and 0.79 (0.07) in female, and it was high in males in the last decades. CONCLUSION: The present study points out the high prevalence of obesity in our city and the anthropometric characteristics and reference values of body composition in the normal population of L'Hospitalet de Llobregat, remarking the high body mass index in the last decades, especially in women due to an increase of fat mass. The waist-hip ratio was high in males in the last decades.

[The efficacy of the radioiodine treatment of toxic thyroid adenoma and multinodular goiter]. / Eficacia del tratamiento con radioyodo del adenoma tiroideo y bocio multinodular tóxicos.

OBJECTIVE: To investigate the effect of radioiodine therapy of thyroid adenoma (TA) and toxic multinodular goitre (TMG) on function and thyroid volume. MATERIALS AND METHODS: Prospective study which includes 14 consecutive patients with TA and 15 with TMG treated with radioiodine and followed for two years. The therapeutic dose was fixed at 15 mCi for TA and 150 microCi x g of thyroid tissue/uptakes at 6 h (mean dose: 14.4 +/- 4.1 mCi) for TMG. Thyroid function and echographic thyroid volume were determined before and at 1, 3, 6, 12 and 24 months. RESULTS: 90% of patients with TA and 80% with TMG recovered euthyroidism at the third month. One patient with TA and three with TMG required two doses. The latter patients were the only ones with hypothyroidism at two years. The TA volume decreased from 20 +/- 8.5 ml to 10.4 +/- 8.1 ml at two years (p = 0.004). The extranodular thyroid volume did not change (initial: 16.4 +/- 10.4 ml versus 15.6 +/- 3.8 ml at the second year). The thyroid volume in TMG decreased from 66.5 +/- 28 ml to 39.8 +/- 13.5 ml at two years (p = 0.006). The largest reductions for TA and TMG were 54% and 38%, respectively, within the first six months. Only one patient with TA and another patient with TMG had their volumes transiently increased, lower than 10%. CONCLUSIONS: Therapy with radioiodine of TA and TMG achieves a rapid recovery of euthyroidism and a gradual decrease in thyroid volume with a low incidence of hypothyroidism, with no additional secondary effects. It has proved to be a valid alternative to surgical therapy.

[Changes in body composition in adult patients with hypopituitarism after substitutive treatment with growth hormone]. / Modificaciones de la composición corporal en pacientes adultos con hipopituitarismo después del tratamiento sustitutivo con hormona del crecimiento.

BACKGROUND: Adult growth hormone (GH) deficiency is associated with changes in body composition, with lower total body water (TBW) and fat free mass (FFM) and higher fat mass (FM). These changes can be modified after sustitutive treatment with GH. PATIENTS AND METHODS: We studied 20 patients, 14 males and 6 females with hypopituitarism and GH deficiency, the mean age was 40.3 years, as well as 20 comparable controls. The diagnosis of GH deficiency was based on the lack of GH response after an hypoglycemic test. We determined body composition by bioelectrical impedance. An initial 6 month double-blind placebo controlled phase was followed by an open treatment phase ending when the patients had received GH for 18 or 24 months. The initial dose was 0.125 U/kg/week during the first month and after 0.25 U/kg/week. RESULTS: The patients showed lower TWB and FFM and higher BF in relation to controls and after 3 months of GH treatment an increase of the TBW, FFM and a decrease in BF and waist/hip ratio was observed with a steady state in the changes of body composition after 3 months that continued 6 months after the GH treatment withdraw. Two patients presented maleolar oedema, 4 arterial hypertension that was settled with GH dose reduction and in the fourth patient the treatment had to be withdraw. Three patients presented carpal tunnel syndrome. In 4 patients the treatment was withdrawn. CONCLUSIONS: In patients with adult GH deficiency, we can observe differences in the body composition that can be significantly modified by GH treatment.

[Changes in the lipid profile and thyroid function in adult patients with hypopituitarism after substitutive treatment with growth hormone]. / Modificaciones del perfil lipídico y de función tiroidea en pacientes adultos con hipopituitarismo tras tratamiento sustitutivo con hormona del crecimiento.

BACKGROUND: Adult growth hormone (GH) deficiency is associated with changes in serum lipid levels that can modify after GH substitution. METHODS: We studied 18 patients with GH deficiency treated with GH for 18 or 24 months. RESULTS: A decrease of total cholesterol, LDL with an increase in HDL without triglycerides changes was observed. T4 levels decreased and T3 increased. CONCLUSIONS: The GH substitution treatment in patients with GH deficiency improves the lipid profile and promotes the T4 to T3 conversion.

[Results of treatment of Graves-Basedow disease with 131I at low calculated doses]. / Resultados del tratamiento de la enfermedad de Graves Basedow con 131I a dosis bajas calculadas.

OBJECTIVE: To evaluate the results of treatment of Graves' disease with 131I at low calculated doses. METHODS: A total of 333 patients with Graves' disease were treated with low calculated doses of 131I on the basis of thyroid size and 131I uptake (mean doses = 6.6 +/- 1.9 mCi). The mean follow-up was 24.4 months (range 12-145). RESULTS: The accumulated likelihood of hypothyroidism at 145 months of follow-up was 89.8% (Kaplan-Meier method) and relapse 26%. Pretreatment levels of T3 above 9 nmol/l were associated with a lower incidence of hypothyroidism (p = 0.049, Mantel-Cox method). Pretreatment levels of T4 above 300 nmol/l were associated with a higher risk of therapy failure (odds ratio 3.27; 95% confidence interval = 1.3-8.2, Cox method). Age, sex, previous therapy with anti-thyroid agents or surgery, 131I uptake, initial and total dose of 131I, number of administered doses and development of transient hypothyroidism were not predictive of the evolution of thyroid function. CONCLUSION: Therapy of hyperthyroidism (Graves' disease) with low calculated doses of 131I shows a high incidence of hypothyroidism, also increasing the cost involved in estimating the dose and long-term follow-up.

[Prevalence and significance of lymphocyte infiltration in papillary carcinoma of the thyroid gland]. / Prevalencia y significado de la infiltración linfocitaria en el carcinoma papilar del tiroides.

OBJECTIVE: We have investigated the prevalence, signification and prognostic value of lymphocytic infiltration associated to differentiated thyroid carcinoma in our series of differentiated carcinoma of the thyroid. METHODS: We studied the presence of lymphocytic infiltration in 223 patients effected of differentiated thyroid carcinoma, 138 of them were papillary carcinoma. The diagnostic was made with optic microscopy and we studied antithyroid antibodies in these patients. In survival analysis we studied all the variables of the patients and the event used as end point was death due to thyroid carcinoma, summarized in Kaplan-Meir curve and Cox method. RESULTS: We found eight patients with differentiated thyroid carcinoma, six with papillary carcinoma, and lymphocytic thyroiditis and in three cases, antithyroid antibodies were present at low levels. We did not found any difference between the two groups and the survival rate was similar. CONCLUSIONS: These data support that in our series the prevalence of lymphocytic infiltration was low and probably without prognostic signification.

[Identification and validation of prognostic factors in differentiated thyroid carcinoma]. / Identificación y validación de factores pronósticos del cáncer diferenciado de tiroides.

BACKGROUND: The aims of this study are to identify prognostic factors of differentiated thyroid carcinoma and to validate the application of prognostic classifications obtained by others studies to another population. PATIENTS AND METHODS: The survival of 208 patients with differentiated thyroid carcinoma (129 papillary and 79 follicular carcinoma) was calculated by the Kaplan-Meier method. The mean follow-up was 7.5 years (1-17.7). Cox-proportional hazard model was used for variables influencing on survival (Mantel-Cox method). In addition, the EORTC, AGES, AJC, AMES and DeGroot classifications were tested. RESULTS: The independent prognostic factors identified were patient age > 60 years, tumor size > 6 cm and the presence of distant metastases. The absence of poor prognostic factors defined the low risk group (153 patients, survival 97% at 17.7 years of follow-up). The application of the other prognostic classifications differentiated several risk groups not in accordance with those obtained in the initial population. CONCLUSIONS: In this series of patients with thyroid carcinoma the main prognostic factors were age, tumor size and the presence of distant metastases. However, there are pitfalls in applying the prognostic classifications of published studies to another population.

Expression of wild-type p53 in human A673 cells suppresses tumorigenicity but not growth rate.

The p53 gene has been found to be mutated in many different kinds of human cancers. In a previous study, expression of exogenous wild-type p53 in human osteosarcoma cells by retrovirus-mediated gene transfer resulted in marked enlargement of cell size, reduced growth rate in culture and loss of tumorigenicity in nude mice. Here we examine the effects of expression of wild-type or mutated p53 on human peripheral neuroepithelioma (PNET) A673 cells; these cells contained apparently normal alleles of the p53 gene but did not express a detectable quantity of p53 protein. Various characteristics of the p53-expressing cells were examined including morphology, growth rate, soft-agar colony formation, and tumorigenicity in nude mice. In contrast to osteosarcoma Saos-2 cells, expression of wild-type or mutant p53 protein in A673 cells had no effect on morphology or growth characteristics. However, clones expressing wild-type p53 protein had reduced ability to form colonies in soft agar and tumors in nude mice. To substantiate the genotype of wild-type p53-expressing cells, the proviral p53-encoding DNA of one cell clone was amplified by the polymerase chain reaction and sequenced. We concluded that expression of a single allele of the wild-type p53 gene was sufficient to suppress PNET A673 tumorigenicity but had no detectable effect on growth rate in culture.