Andres Sanchez - Academia.edu (original) (raw)

Papers by Andres Sanchez

International Journal of Dermatology, 2004

Tetracyclines (TCN) were introduced in 1948 as broad-spectrum antibiotics that may be used in the... more Tetracyclines (TCN) were introduced in 1948 as broad-spectrum antibiotics that may be used in the treatment of many common infections in children and adults. One of the side-effects of tetracyclines is incorporation into tissues that are calcifying at the time of their administration.

Laryngoscope, 1989

Laryngeal tuberculosis continues to exist in spite of extensive tuberculosis eradication campaign... more Laryngeal tuberculosis continues to exist in spite of extensive tuberculosis eradication campaigns. We present 19 cases of laryngeal tuberculosis seen in our institution between 1982 and 1987. From the clinical findings it is clear that the localization of the lesions has changed since the preantibiotic era. Today the spread appears to be mainly via lymphatic and hematogenic routes, as opposed to the direct spread more common previously. The fibrosis caused by the lesions is incapacitating and frequently requires surgical correction.

Pace-pacing and Clinical Electrophysiology, 1997

MADRID, A., ET AL.: Dysfunction of Implantable Defibrillators Caused by Slot Macbines. The electr... more MADRID, A., ET AL.: Dysfunction of Implantable Defibrillators Caused by Slot Macbines. The electrogram storage is a feature offered by the last generation of defibrillators, which enables the physician to establish whether the sensed episode and the electrical therapy delivered by the device was appropriate. The incidence of electromagnetic interferences may be higher than initially suspected with the latest generation of defibrillators. Such interference was documented in 4 out of 100 patients over a 24-month period. The electrical interference occurred in all four of them, while they were playing with slot machines. In the RR interval history, irregular QRS sensing of variable frequency was documented in some episodes. The intervals were irregular and nonphysiological, satisfying the rate cut-off criteria in an intermittent and nonsustained way. There maybe high risk of electromagnetic interference between slot machines and defibrillators. Our experience calls for a warning to all defibrillator patients and, perhaps some regulatory intervention. (PACE 1997; 20[Pt. 111:212-214) defibrillators, electromagnetic interference, slot machines

Journal of Chromatography B: Biomedical Sciences and Applications, 1999

The work presents an analytical strategy to detect drugs of abuse in hair. It involves two sequen... more The work presents an analytical strategy to detect drugs of abuse in hair. It involves two sequential steps: a screening by a simple enzyme-linked immunosorbent assay (ELISA) methodology to detect opiates, cocaine and its metabolites, and benzodiacepines, followed by confirmation of opiates and cocaine metabolites in positive samples by gas chromatography coupled to mass spectrometry (GC-MS). In the same GC-MS run other drugs for substitution therapy (e.g. methadone and its main metabolite) can also be detected. After a double washing of hair samples with dichloromethane, hair specimens were cut into small pieces and 10 mg samples were incubated in 2 ml of methanol-trifluoroacetic acid (9:1) mixture, overnight at 37 degrees C. Aliquots of the extract were then evaporated, reconstituted in buffer and analysed according to the ELISA procedure. Confirmation involved solid-phase extraction of another fraction of the extract kept at -20 degrees C, derivatization with heptafluorobutyric anhydride and hexafluoroisopropanol and detection of cocaine, benzoylecgonine, ecgonine methylester, cocaethylene, morphine, codeine, 6-monoacetylmorphine, methadone and 2-ethylidene-1.5-dimethyl-3,3-diphenylpirrolidine (methadone metabolite) by selective ion monitoring after gas chromatographic separation. During the development of the method it was verified that no more than 10% of cocaine, opiates and benzodiacepines were lost when dichloromethane was used to wash real samples. The results also confirmed the increase of extractability power of TFA when it was added to methanol: the recovery for the analytes (cocaine and its metabolites and opiates) added to methanol-TFA alone was of the order of 90% except for benzoylecgonine (75%), and the recovery for the analytes added to methanol-TFA extract of drug-free hair was about 90% for all analytes except for benzoylecgonine and 6-MAM (around 70%). Regarding the stability of labile compounds, only small amounts of ecgonine methylester (2.3%) and morphine (7.2%) were produced, from cocaine and 6-MAM respectively, after the whole extraction procedure and two weeks of storage of methanol-TFA extracts at -20 degrees C. Satisfactory results were obtained when the procedures were applied to the analysis of external proficiency testing hair samples and actual specimens from drug addicts.

New England Journal of Medicine, 1997

It has recently been suggested 2 , 3 that mutations within the sulfonylurea receptor, a subunit o... more It has recently been suggested 2 , 3 that mutations within the sulfonylurea receptor, a subunit of the ATP-sensitive potassium (K atp ) channel present in the plasma membrane of pancreatic beta cells, are associated with ...

Land Use Policy, 2001

Southeastern Spain is the driest region of Western Europe. Rainfall ranges between 200 and 300 mm... more Southeastern Spain is the driest region of Western Europe. Rainfall ranges between 200 and 300 mm/year. Near-desert landscapes, without trees and covered by shrubs, dominate the zone. According to the traditional view, these landscapes existed before any anthropogenic processes of degradation began. However, historical documents and place-names demonstrate that forests played an important role in this territory up to the 19th century and that a great diversity of fauna prevailed, including such forest species as bear, lynx, deer and roe deer. In this paper we will show how economic activities and demographic pressure on these fragile ecosystems changed them irreversibly in a short time. We develop a historical analysis of the relationships between human activities and the environment from the end of the Islamic period (16th century) up until the 20th century, focusing especially on agriculture, mining and demography. The starting point is a sparsely populated territory, inhabited by Muslim peasant communities. Their agriculture was based on the irrigation of small areas and on a system of agroforestry. The continued existence of rich forest ecosystems and fauna in this arid zone could be explained by low demographic pressure and a special land-use system. Beginning in the 16th century enormous socioeconomic changes contributed to the creation of the present desert situation. The formation of today's semi-desert landscapes took place in large part over a brief period (19th century). Mining and the accompanying large consumption of wood, agricultural expansion, and a demographic explosion destroyed the forests and totally altered the ecosystems.

Journal of Agricultural and Food Chemistry, 2005

The antimicrobial activity of essential oils (EOs) of cinnamon (Cinnamon zeylanicum), clove (Syzy... more The antimicrobial activity of essential oils (EOs) of cinnamon (Cinnamon zeylanicum), clove (Syzygium aromaticum), basil (Ocimum basillicum), rosemary (Rosmarinus officinalis), dill (Anethum graveolens), and ginger (Zingiber officinalis) was evaluated over a range of concentrations in two types of contact tests (solid and vapor diffusion). The EOs were tested against an array of four Gram-positive bacteria (Staphylococcus aureus, Bacillus cereus, Enterococcus faecalis, and Listeria monocytogenes), four Gram-negative bacteria (Escherichia coli, Yersinia enterocolitica, Salmonella choleraesuis, and Pseudomonas aeruginosa), and three fungi (a yeast, Candida albicans, and two molds, Penicillium islandicum and Aspergillus flavus). The rationale for this work was to test the possibility of creating a protective atmosphere by using natural compounds that could extend the shelf life of packaged foodstuffs while minimizing organoleptic alterations. In the solid diffusion tests, cinnamon and clove gave the strongest (and very similar) inhibition, followed by basil and rosemary, with dill and ginger giving the weakest inhibition. The fungi were the most sensitive microorganisms, followed by the Gram-positive bacterial strains. The Gram-negative strain P. aeruginosa was the least inhibited. The composition of the atmosphere generated by the EOs, and their minimum inhibitory concentrations (MICs), were determined using a disk volatilization method, in which no inhibition from rosemary or basil was observed. Cinnamon and clove, once again, gave similar results for every microorganism. As a general rule, MIC (fungi) < MIC (bacteria) with no clear differences between Gram-positive or -negative strains except for P. aeruginosa, which was not inhibited by any of the EOs in the vapor phase. The atmosphere generated from the EOs was analyzed by means of solid-phase microextraction combined with gas chromatography-ion trap mass spectrometry. Differences among the volatiles in the EOs, which may be responsible for the differences in their antimicrobial performances, were found.

Energy Conversion and Management, 2008

Postcombustion CO 2 capture is the best suitable capture technology for existing coal power plant... more Postcombustion CO 2 capture is the best suitable capture technology for existing coal power plants. This paper focuses on an emerging technology that involves the separation of CO 2 using the reversible carbonation reaction of CaO to capture CO 2 from the flue gas, and the calcination of CaCO 3 to regenerate the sorbent and produce concentrated CO 2 for storage. We describe the application to this concept to an existing (with today's technology) power plant. The added capture system incorporates a new supercritical steam cycle to take advantage of the large amount of heat coming out from the high temperature capture process (oxyfired combustion of coal is needed in the CaCO 3 calciner). In these conditions, the capture system is able to generate additional power (26.7% efficiency respect to LHV coal input to the calciner after accounting for all the penalties in the overall system), without disturbing the steam cycle of the reference plant (that retains its 44.9 efficiency). A preliminary cost study of the overall system, using well established analogues in the open literature for the main components, yields capture cost around 16 €/ton CO 2 avoided and incremental cost of electricity of just over 1 €/MW h e.

Materials Science Forum, 1996

ABSTRACT A European consortium is designing a supersonic transport aircraft to replace Concorde f... more ABSTRACT A European consortium is designing a supersonic transport aircraft to replace Concorde for which it is currently proposed to use aluminium alloys for the fuselage. The requirement is for a material that has creep resistance and damage tolerance better than the Concorde alloy 2618A and promising results have been obtained with extruded Al-Cu-Mg-Ag alloys hardened mainly by the Ω precipitate. Data is presented which shows that the tensile properties and creep performance of these alloys are generally superior to that of competing commercial alloys of the 2000 series.

Journal of Applied Polymer Science, 2000

ABSTRACT The reactions of two cellulosic materials (an industrial cellulosic by-product from a Kr... more ABSTRACT The reactions of two cellulosic materials (an industrial cellulosic by-product from a Kraft pulp mill facility and a reference material) with three coupling agents, used to improve compatibility between cellulosic reinforcements and thermoplastic matrices, were studied by diffuse reflectance Fourier-transform infrared (DRIFT) spectroscopy and diffuse reflectance ultraviolet-visible spectroscopy. A maleated polypropylene wax (Epolene E-43™) and two silanes (N-2-aminoethyl-3-aminopropyltrimethoxysilane and methyltrimethoxysilane) were used as coupling agents. The two cellulosic materials reacted in a similar way and the three coupling agents were covalently bonded to the cellulose. For the aminosilane, a reaction with cellulose involving a fraction of the amino groups was detected. A simple method, based on the analysis of the oxidation kinetics of treated and untreated materials, was developed to compare the degree of cellulose modification achieved by each coupling agent. The analysis revealed that a reduced fraction of the cellulose reactive groups was converted by esterification with the maleated polypropylene. However, when applied in the appropriate conditions, the two silanes converted most of such cellulose reactive groups. Finally, the reaction of cellulose with mixtures of coupling agents was studied. The aminosilane-treated cellulose reacted with the maleated polypropylene with formation of amide links. © 2000 John Wiley & Sons, Inc. J Appl Polym Sci 75: 256–266, 2000