76 research outputs found

    PCDD/F formation from chlorophenols by lignin and manganese peroxidases

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    Polychlorinated dibenzo-p-dioxins and polychlorinated dibenzofurans (PCDD/F) formation was studied, in vitro, with two different chlorophenol mixtures (group “di+tri” 2,4-dichlorophenol; 2,3,4-, 2,3,5-, and 3,4,5-trichlorophenols and group “tri+tetra+penta” with 2,4,5-trichlorophenol, 2,3,4,6-tetrachlorophenol and pentachlorophenol) and two different lignolytic enzymes, lignin and manganese peroxidase (LiP and MnP respectively), which can be found during the composting process of sewage sludge. The concentrations of PCDD/F in final samples are compared to the PCDD/F content of the control samples containing the chlorophenols. High increases were observed for experiments with MnP and phosphate buffer. Experiments that contained tri-, tetra- and pentachlorophenol with MnP resulted in more than 8 · 108 ng of OCDD kg−1 chlorophenol which was much higher than the initial amount (1 · 107 ng OCDD kg−1 chlorophenol). In relation to LiP experiments, only those at 37 °C showed a moderate increase (from 1.3 · 107 to 2.6 · 107 ng of OCDD kg−1 chlorophenol). The results agree with the literature in which high amounts of HpCDD and OCDD were found after a composting process and could explain the biogenic formation suggested by others, but the incidence on the total toxicity is less than that expected.The authors want to thank the University of Alicante for their economic support to perform this research and the project CTQ 2008-05520 of the Spanish Ministry of Science and Innovation, Prometeo 2009/043/FEDER of the Valencian Community of Spain

    Analysis of the vaporization process in TG apparatus and its incidence in pyrolysis

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    An analysis of the evaporation process of n-hexadecane in a thermogravimetric apparatus was carried out. n-Hexadecane represents a typical example of a high boiling point compound and its study is interesting for understanding those processes where vaporization takes place in parallel with pyrolysis during thermal treatment. The process has been studied under different operating conditions: nitrogen and air atmospheres, and isothermal and dynamic runs with three different heating rates from 5 K/min to 20 K/min. The experimental data were satisfactorily correlated to a n-order model with zero process order and the same apparent activation energy for all runs, but the exponential factors of the different runs depended on the initial mass and the heating rate. The experimental results were compared with those predicted considering the diffusion process inside the crucible, taking into account the vapor pressure and the diffusion coefficient of n-hexadecane. A parameter, product of these two variables, can be estimated from a single TG run, so the vaporization process in other equipment and/or operating conditions can also be estimated.Support for this work was provided by PROMETEO/2009/043/FEDER and ACOMP2010/075 of Generalitat Valenciana (Spain) and CTQ2008-05520 (Spanish MCI/research)

    Characterization of lorry washing sludge

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    The sludge generated by washing lorry refuse and some fractions of municipal solid waste have been studied, to justify that washing sludge presents no danger and can therefore be managed adequately in a landfill, as well as other municipal solid waste fractions. One problem attributed to this type of sludge is its high level of sulfide content, which causes this waste to be considered hazardous. The determination of sulfide content in the studied samples was carried out according to environmental protection agency methods 9030B and 9034, and the results show that the sulfide concentration in the sludge is less than other fractions of the municipal solid waste treatment plants, which can properly composted, in which sulfides are oxidized to sulfates. Lorry washing sludge could therefore be managed in a municipal solid waste treatment plant

    Immunomodulatory drugs: oral and systemic adverse effects

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    Objectives: The main objectives are to present the different adverses effects of the immunomodulatory drugs that can impair the quality of life of the immunosupressed patients and study the impact of immunomodualtion on oral diseases. Immunomodulatory drugs have changed the treatment protocols of many diseases where immune functions play a central role, such as rheumatic diseases. Their effect on oral health has not been systematically investigated, however. Study Design: We review current data on the new immunomodulatory drugs from the oral health perspective based on open literature search of the topic. Results: These target specific drugs appear to have less drug interactions than earlier immunomodulating medicines but have nevertheless potential side effects such as activating latent infections. There are some data showing that the new immunomodulatory drugs may also have a role in the treatment of certain oral diseases such as lichen planus or ameliorating symptoms in Sjögren´s syndrome, but the results have not been overly promising. Conclusions: In general, data are sparse of the effect of these new drugs vs. oral diseases and there are no properly powered randomized controlled trials published on this topic

    Osteochemonecrosis of the jaws due to bisphosphonate treatments : update

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    Bisphosphonates (BP),were initially used in industry and later as a drug due to their great affinity to osseous tissue, because of their powerful antiresorptive effect as a treatment in various osteopathies, such as osteoporosis, Paget disease or hypercalcemia associated with some malignant tumors, as myeloma or breast cancer. They are administered orally or intravenously, and although well tolerated, the most frequent side effects are gastrointestinal, in addition to osteonecrosis when they are administered via endovenous. The aim of this work has been to evaluate the existing publications in accredited scientific literature on biphosphonates and their action mechanism and the relationship with the appearance of osteonecrosis of the jaws. Although the mechanism by which osteonecrosis of the jaws develops is not known exactly, there seems to be influence by osteoclast inhibiton, antiangiogenic action, an inhibitory effect on the cellular cycle by the keratinocytes, as well as, reinforcement of the chemiotoxic action in oncological patients treated with other drugs. Clinically, it ranges from a non-specificity of symptoms to lesions such as osteomyelitis with necrosis and osseous sequesters that may be accompanied by fetor ex oris, with the appearance of many Actinomyces contaminated lesions. As for published antecedents on osteonecrosis due to bisphosphonate treatment found until 2006: 46.5% had a previous diagnosis of multiple myeloma; 38.8% were patients with metastatic breast cancer; 6.2% patients of metastatic prostate cancer; 4.1% suffered from osteoporosis; 3.5% from other metastatic diseases and 0.8% had Paget disease. The drugs that seem to have the highest incidence of osteochemionecrosis are: zoledronate, pamidronate, alendronate, risendronate and ibandronate, from the greatest to the least. Additionally, the risk of osteonecrosis being produced is accumulative and may reach 21% in the third year of intravenous bisphosphonate use

    Influencia del hábito tabáquico en el postoperatorio de la cirugía del tercer molar inferior

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    Objetivos: Determinar si tras la cirugía del tercer molar inferior el tabaco influye en el postoperatorio (dolor y trismo) y valorar clínicamente el estado de la herida, analizando las posibles diferencias entre fumadores y no fumadores. Diseño del estudio: Los pacientes que participaron en el estudio fueron distribuidos de forma aleatoria en dos grupos: Fumadores y no fumadores. Se les realizó la extracción quirúrgica de los terceros molares inferiores en la Unidad de Cirugía Bucal y Maxilofacial de la Universidad Complutense de Madrid. Las variables registradas fueron el trismo a los 7 días, la intensidad del dolor y la necesidad de medicación de rescate durante un periodo de una semana. Se analizó también el estado de la herida (coloración, presencia de placa, etc.) Resultados: Hubo dos casos de infección postoperatoria en el grupo de pacientes fumadores. El trismo postoperatorio fue mayor en los fumadores (p=0.05) Conclusiones: No hubo diferencias estadísticamente significativas en cuanto a dolor, pero sí se observó un mayor trismo en el grupo de fumadores. El tabaco no influyó en el estado de la herida ( color, inflamación de los bordes, confrontación de los mismos, ulceración, etc.).Objectives: To determine whether smoking influences the postoperative course (pain and trismus) of lower third molar surgery, with a clinical evaluation of surgical wound condition and analysis of the possible differences between smokers and nonsmokers. Design: The study subjects were randomly distributed into two groups (smokers and nonsmokers) and subjected to lower third molar extraction in the Unit of Oral and Maxillofacial Surgery (Madrid Complutense University, Spain). The study variables were trismus after 7 days, the intensity of pain and the need for rescue medication during a period of one week. The surgical wound was also assessed (color, presence of plaque, etc.). Results: Two cases of postoperative infection were documented among the smokers, and postoperative trismus was found to be greater among the latter (p=0.05). Conclusions: There were no statistically significant differences between the two groups in terms of pain, though trismus was greater among the smokers. Smoking did not influence wound condition (color, marginal inflammation, appositioning of the margins, ulceration, etc.)

    Influence of smoking upon the postoperative course of lower third molar surgery

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    Objectives: To determine whether smoking influences the postoperative course (pain and trismus) of lower third molar surgery, with a clinical evaluation of surgical wound condition and analysis of the possible differences between smokers and nonsmokers. Design: The study subjects were randomly distributed into two groups (smokers and nonsmokers) and subjected to lower third molar extraction in the Unit of Oral and Maxillofacial Surgery (Madrid Complutense University, Spain). The study variables were trismus after 7 days, the intensity of pain and the need for rescue medication during a period of one week. The surgical wound was also assessed (color, presence of plaque, etc.). Results: Two cases of postoperative infection were documented among the smokers, and postoperative trismus was found to be greater among the latter (p=0.05). Conclusions: There were no statistically significant differences between the two groups in terms of pain, though trismus was greater among the smokers. Smoking did not influence wound condition (color, marginal inflammation, appositioning of the margins, ulceration, etc.)

    Evaluation of p53, Caspase-3, Bcl-2, and Ki-67 markers in oral squamous cell carcinoma and premalignant epithelium in a sample from Alava Province (Spain)

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    Objectives: The objective of this study was to determine whether alterations in the expression of p53, caspase-3 Bcl-2, and ki-67 appear early in premalignant oral epithelium and show clonal behavior. Study Design: Samples from 41 tumors with their adjacent non-tumor epithelia were immunohistochemically analyzed using monoclonal antibodies that recognize p53, caspase-3, Bcl-2, and Ki-67 Results: A statistically significant association was found between the expression in tumor and adjacent epithelium of p53, caspase-3, and Bcl-2 but not of k-67. A significant association was observed between the expression of ki-67 and p53 in both localizations. In non-tumor (premalignant) epithelium samples, there was a significant inverse relationship between the expressions of p53 and caspase-3 and a significant direct relationship between the expressions of p53 and Bcl-2. Conclusions: Alterations in these proteins appear to operate in combination with premalignant epithelia to create hyperproliferative cell states that favor the acquisition of summative oncogenic errors that confer invasive capacity

    Quantification of Total Phenolic and Carotenoid Content in Blackberries (Rubus Fructicosus L.) Using Near Infrared Spectroscopy (NIRS) and Multivariate Analysis

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    A rapid method to quantify the total phenolic content (TPC) and total carotenoid content (TCC) in blackberries using near infrared spectroscopy (NIRS) was carried out aiming to provide reductions in analysis time and cost for the food industry. A total of 106 samples were analysed using the Folin-Ciocalteu method for TPC and a method based on Ultraviolet-Visible Spectrometer for TCC. The average contents found for TPC and TCC were 24.27 mg·g−1 dw and 8.30 µg·g−1 dw, respectively. Modified partial least squares (MPLS) regression was used for obtaining the calibration models of these compounds. The RPD (ratio of the standard deviation of the reference data to the standard error of prediction (SEP)) values from external validation for both TPC and TCC were between 1.5 < RPDp < 2.5 and RER values (ratio of the range in the reference data to SEP) were 5.92 for TPC and 8.63 for TCC. These values showed that both equations were suitable for screening purposes. MPLS loading plots showed a high contribution of sugars, chlorophyll, lipids and cellulose in the modelling of prediction equations
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