Introducción y objetivos. Se dispone de escasa información sobre el control de la hipertensión ar... more Introducción y objetivos. Se dispone de escasa información sobre el control de la hipertensión arterial en la población de mayor edad. El objetivo de este estudio fue analizar el grado de control de la hipertensión arterial en una amplia muestra de españoles ≥ 65 años asistidos en atención primaria, los factores asociados al mal control y la conducta del médico ante esa situación.
The comparative protective efficacy of culture-derived Babesia bovis and B. bigemina immunogens a... more The comparative protective efficacy of culture-derived Babesia bovis and B. bigemina immunogens against challenge exposure of susceptible crossbred cattle to heterologous strains was examined and correlated with the antigenic threshold requirements for induction of protective immunity. Strong protection was observed in animals vaccinated with 10 ml-equivalent doses of soluble, B. bovis exoantigen-containing supernatant fluids. Similar protective responses to B. bigemina exoantigens were evident even at 1 ml-equivalent dosages. In addition, the efficacy of a combined B. bovis-B. bigemina immunogen was assessed with a dose-response analysis in highly susceptible, purebred cattle. Vaccinated animals were protected against clinical babesiosis, and significant weight gains were recorded after challenge infection with virulent parasites.
Streptococcus pneumoniae colonizes the human upper respiratory tract, and this asymptomatic colon... more Streptococcus pneumoniae colonizes the human upper respiratory tract, and this asymptomatic colonization is known to precede pneumococcal disease. In this report, chemically defined and semisynthetic media were used to identify the initial steps of biofilm formation by pneumococcus during growth on abiotic surfaces such as polystyrene or glass. Unencapsulated pneumococci adhered to abiotic surfaces and formed a three-dimensional structure about 25 m deep, as observed by confocal laser scanning microscopy and low-temperature scanning electron microscopy. Choline residues of cell wall teichoic acids were found to play a fundamental role in pneumococcal biofilm development. The role in biofilm formation of choline-binding proteins, which anchor to the teichoic acids of the cell envelope, was determined using unambiguously characterized mutants. The results showed that LytA amidase, LytC lysozyme, LytB glucosaminidase, CbpA adhesin, PcpA putative adhesin, and PspA (pneumococcal surface protein A) mutants had a decreased capacity to form biofilms, whereas no such reduction was observed in Pce phosphocholinesterase or CbpD putative amidase mutants. Moreover, encapsulated, clinical pneumococcal isolates were impaired in their capacity to form biofilms. In addition, a role for extracellular DNA and proteins in the establishment of S. pneumoniae biofilms was demonstrated. Taken together, these observations provide information on conditions that favor the sessile mode of growth by S. pneumoniae. The experimental approach described here should facilitate the study of bacterial genes that are required for biofilm formation. Those results, in turn, may provide insight into strategies to prevent pneumococcal colonization of its human host.
Biochemical and Biophysical Research Communications, 1989
A new lytic enzyme isolated from Streptococcus ~neumoniae has been purified to electrophoretical ... more A new lytic enzyme isolated from Streptococcus ~neumoniae has been purified to electrophoretical homogeneity.--Tfie-6fi~66~ ~R5~ifi~--a Mr of b4000, ~as been characterized as an endo-~-l,4-N-acetylglucosaminxdase-that requires choline in the teichoic ~i~ -of t~ cell wall substrata for catalytic activity. In vivo experiments demonstrate that the glucosaminidase behaves as an autolytic enzyme.
Oligonucleotide-directed mutagenesis of a plasmid containing the lytA gene coding for the pneumoc... more Oligonucleotide-directed mutagenesis of a plasmid containing the lytA gene coding for the pneumococcal amidase has allowed the separation of the coding sequence of the gene. This sequence has been placed in plasmid pIN-III(lppP-5)-A3 downstream from both a modified lipoprotein promoter and the lactose promoter to construct the recombinant plasmid pGL100. When Escherichia coli RB 791 (pGL100) was grown in the presence of lactose, the pneumococcal amidase accounted for 7% of the total protein present in this strain after 18 h incubation at 37°C. The overproduced amidase was purified in a single-step procedure using a choline-Sepharose 6B column taking advantage of the fact that this enzyme was the unique protein with affinity for choline present in extracts obtained from E. coli RB791 (pGL100). The development of the above design opens up the possibility of studying the mechanism that regulates the activity of this important autolysin by using physicochemical techniques that require the availability of high amounts of purified amidase.
... sequence and expression of the pneumococcal autolysin gene from its own promoter in Escherich... more ... sequence and expression of the pneumococcal autolysin gene from its own promoter in Escherichia coli (Recombinant DNA; ^-lactam antibiotics; hydrophobic regions; ribosome-binding site; plasmids; trans-formation; Streptococcus pneumoniae) Pedro Garcia, Jos Luis Garcia ...
We have used a variety of techniques to correct left ventricular outflow tract obstructions, incl... more We have used a variety of techniques to correct left ventricular outflow tract obstructions, including, in the past, placement of an apicoaortic valved conduit to bypass the outflow tract. Because the operation was technically difficult, it had fallen into disuse. Recently, we used a simplified transthoracic approach to implant apicoaortic conduits in 7 patients with complex lesions of the left ventricular outflow tract. The thoracic cavity was entered through the fifth intercostal space in all 7 patients. The distal end of the valve-containing conduit was attached to the aorta with continuous 3-0 or 4-0 polypropylene sutures after incising the pleura over the distal descending aorta. The pericardium was opened to expose the left ventricular apex, which was cored so that the proximal end of the conduit could be inserted into the left ventricular cavity. Five of the patients recovered completely. The 2 patients who died had severe heart disease and multiple comorbidities. The transthoracic approach gives direct access to the descending aorta and avoids a redo sternotomy. The technique, which is simple to perform, does not compromise major coronary arteries, the conduction system, or other valves; and may be useful in patients who are not good candidates for other, more conventional procedures.
Introducción y objetivos. Se dispone de escasa información sobre el control de la hipertensión ar... more Introducción y objetivos. Se dispone de escasa información sobre el control de la hipertensión arterial en la población de mayor edad. El objetivo de este estudio fue analizar el grado de control de la hipertensión arterial en una amplia muestra de españoles ≥ 65 años asistidos en atención primaria, los factores asociados al mal control y la conducta del médico ante esa situación.
The comparative protective efficacy of culture-derived Babesia bovis and B. bigemina immunogens a... more The comparative protective efficacy of culture-derived Babesia bovis and B. bigemina immunogens against challenge exposure of susceptible crossbred cattle to heterologous strains was examined and correlated with the antigenic threshold requirements for induction of protective immunity. Strong protection was observed in animals vaccinated with 10 ml-equivalent doses of soluble, B. bovis exoantigen-containing supernatant fluids. Similar protective responses to B. bigemina exoantigens were evident even at 1 ml-equivalent dosages. In addition, the efficacy of a combined B. bovis-B. bigemina immunogen was assessed with a dose-response analysis in highly susceptible, purebred cattle. Vaccinated animals were protected against clinical babesiosis, and significant weight gains were recorded after challenge infection with virulent parasites.
Streptococcus pneumoniae colonizes the human upper respiratory tract, and this asymptomatic colon... more Streptococcus pneumoniae colonizes the human upper respiratory tract, and this asymptomatic colonization is known to precede pneumococcal disease. In this report, chemically defined and semisynthetic media were used to identify the initial steps of biofilm formation by pneumococcus during growth on abiotic surfaces such as polystyrene or glass. Unencapsulated pneumococci adhered to abiotic surfaces and formed a three-dimensional structure about 25 m deep, as observed by confocal laser scanning microscopy and low-temperature scanning electron microscopy. Choline residues of cell wall teichoic acids were found to play a fundamental role in pneumococcal biofilm development. The role in biofilm formation of choline-binding proteins, which anchor to the teichoic acids of the cell envelope, was determined using unambiguously characterized mutants. The results showed that LytA amidase, LytC lysozyme, LytB glucosaminidase, CbpA adhesin, PcpA putative adhesin, and PspA (pneumococcal surface protein A) mutants had a decreased capacity to form biofilms, whereas no such reduction was observed in Pce phosphocholinesterase or CbpD putative amidase mutants. Moreover, encapsulated, clinical pneumococcal isolates were impaired in their capacity to form biofilms. In addition, a role for extracellular DNA and proteins in the establishment of S. pneumoniae biofilms was demonstrated. Taken together, these observations provide information on conditions that favor the sessile mode of growth by S. pneumoniae. The experimental approach described here should facilitate the study of bacterial genes that are required for biofilm formation. Those results, in turn, may provide insight into strategies to prevent pneumococcal colonization of its human host.
Biochemical and Biophysical Research Communications, 1989
A new lytic enzyme isolated from Streptococcus ~neumoniae has been purified to electrophoretical ... more A new lytic enzyme isolated from Streptococcus ~neumoniae has been purified to electrophoretical homogeneity.--Tfie-6fi~66~ ~R5~ifi~--a Mr of b4000, ~as been characterized as an endo-~-l,4-N-acetylglucosaminxdase-that requires choline in the teichoic ~i~ -of t~ cell wall substrata for catalytic activity. In vivo experiments demonstrate that the glucosaminidase behaves as an autolytic enzyme.
Oligonucleotide-directed mutagenesis of a plasmid containing the lytA gene coding for the pneumoc... more Oligonucleotide-directed mutagenesis of a plasmid containing the lytA gene coding for the pneumococcal amidase has allowed the separation of the coding sequence of the gene. This sequence has been placed in plasmid pIN-III(lppP-5)-A3 downstream from both a modified lipoprotein promoter and the lactose promoter to construct the recombinant plasmid pGL100. When Escherichia coli RB 791 (pGL100) was grown in the presence of lactose, the pneumococcal amidase accounted for 7% of the total protein present in this strain after 18 h incubation at 37°C. The overproduced amidase was purified in a single-step procedure using a choline-Sepharose 6B column taking advantage of the fact that this enzyme was the unique protein with affinity for choline present in extracts obtained from E. coli RB791 (pGL100). The development of the above design opens up the possibility of studying the mechanism that regulates the activity of this important autolysin by using physicochemical techniques that require the availability of high amounts of purified amidase.
... sequence and expression of the pneumococcal autolysin gene from its own promoter in Escherich... more ... sequence and expression of the pneumococcal autolysin gene from its own promoter in Escherichia coli (Recombinant DNA; ^-lactam antibiotics; hydrophobic regions; ribosome-binding site; plasmids; trans-formation; Streptococcus pneumoniae) Pedro Garcia, Jos Luis Garcia ...
We have used a variety of techniques to correct left ventricular outflow tract obstructions, incl... more We have used a variety of techniques to correct left ventricular outflow tract obstructions, including, in the past, placement of an apicoaortic valved conduit to bypass the outflow tract. Because the operation was technically difficult, it had fallen into disuse. Recently, we used a simplified transthoracic approach to implant apicoaortic conduits in 7 patients with complex lesions of the left ventricular outflow tract. The thoracic cavity was entered through the fifth intercostal space in all 7 patients. The distal end of the valve-containing conduit was attached to the aorta with continuous 3-0 or 4-0 polypropylene sutures after incising the pleura over the distal descending aorta. The pericardium was opened to expose the left ventricular apex, which was cored so that the proximal end of the conduit could be inserted into the left ventricular cavity. Five of the patients recovered completely. The 2 patients who died had severe heart disease and multiple comorbidities. The transthoracic approach gives direct access to the descending aorta and avoids a redo sternotomy. The technique, which is simple to perform, does not compromise major coronary arteries, the conduction system, or other valves; and may be useful in patients who are not good candidates for other, more conventional procedures.
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Papers by Rubén López