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Biomedical subjects

Carmen Galán

Publications and source records attributed to Carmen Galán.

8 recordsLinked to original sources
PubMed2006

Construction of a severe acute respiratory syndrome coronavirus infectious cDNA clone and a replicon to study coronavirus RNA synthesis.

The engineering of a full-length infectious cDNA clone and a functional replicon of the severe acute respiratory syndrome coronavirus (SARS-CoV) Urbani strain as bacterial artificial chromosomes (BACs) is described in this study. In this system, the viral RNA was expressed in the cell nucleus under the control of the cytomegalovirus promoter and further amplified in the cytoplasm by the viral replicase. Both the infectious clone and the replicon were fully stable in Escherichia coli. Using the SARS-CoV replicon, we have shown that the recently described RNA-processing enzymes exoribonuclease, endoribonuclease, and 2'-O-ribose methyltransferase were essential for efficient coronavirus RNA synthesis. The SARS reverse genetic system developed as a BAC constitutes a useful tool for the study of fundamental viral processes and also for developing genetically defined vaccines.

Animals↗
PubMed2005

The use of discriminant analysis and neural networks to forecast the severity of the Poaceae pollen season in a region with a typical Mediterranean climate.

Biological particles in the air such as pollen grains can cause environmental problems in the allergic population. Medical studies report that a prior knowledge of pollen season severity can be useful in the management of pollen-related diseases. The aim of this work was to forecast the severity of the Poaceae pollen season by using weather parameters prior to the pollen season. To carry out the study a historical database of 21 years of pollen and meteorological data was used. First, the years were grouped into classes by using cluster analysis. As a result of the grouping, the 21 years were divided into 3 classes according to their potential allergenic load. Pre-season meteorological variables were used, as well as a series of characteristics related to the pollen season. When considering pre-season meteorological variables, winter variables were separated from early spring variables due to the nature of the Mediterranean climate. Second, a neural network model as well as a discriminant linear analysis were built to forecast Poaceae pollen season severity, according to the three classes previously defined. The neural network yielded better results than linear models. In conclusion, neural network models could have a high applicability in the area of prevention, as the allergenic potential of a year can be determined with a high degree of reliability, based on a series of meteorological values accumulated prior to the pollen season.

Climate↗
PubMed2005

A point mutation within the replicase gene differentially affects coronavirus genome versus minigenome replication.

During the construction of the transmissible gastroenteritis virus (TGEV) full-length cDNA clone, a point mutation at position 637 that was present in the defective minigenome DI-C was maintained as a genetic marker. Sequence analysis of the recovered viruses showed a reversion at this position to the original virus sequence. The effect of point mutations at nucleotide 637 was analyzed by reverse genetics using a TGEV full-length cDNA clone and cDNAs from TGEV-derived minigenomes. The replacement of nucleotide 637 of TGEV genome by a T, as in the DI-C sequence, or an A severely affected virus recovery from the cDNA, yielding mutant viruses with low titers and small plaques compared to those of the wild type. In contrast, T or A at position 637 was required for minigenome rescue in trans by the helper virus. No relationship between these observations and RNA secondary-structure predictions was found, indicating that mutations at nucleotide 637 most likely had an effect at the protein level. Nucleotide 637 occupies the second codon position at amino acid 108 of the pp1a polyprotein. This position is predicted to map in the N-terminal polyprotein papain-like proteinase (PLP-1) cleavage site at the p9/p87 junction. Replacement of G-637 by A, which causes a drastic amino acid change (Gly to Asp) at position 108, affected PLP-1-mediated cleavage in vitro. A correlation was found between predicted cleaving and noncleaving mutations and efficient virus rescue from cDNA and minigenome amplification, respectively.

Animals↗
PubMed2004

Analysis of the particles transported with dust-clouds reaching Cordoba, southwestern Spain.

Dust-cloud episodes were detected in summer 1999 in the city of Cordoba, southwestern Spain, with a higher frequency than usual. Solid airborne particles were collected using a suction volumetric sampler and analyzed to determine both their nature and their origin. Nonbiological material was mostly identified as mineral sand and partially burned remains of hydrocarbons and stubble. Amounts were estimated in terms of the percentage of microscopic field of view covered. Biological materials, in this case pollen grains, were identified and classified as belonging to either autochthonous or remote flora; in the latter case, the possibility was examined that they might originate in North Africa. Some pollen types were also used as tracers to chart the path followed by the sand clouds within the Iberian Peninsula. Meteorological conditions on the days in which episodes occurred were analyzed. In all cases, very dry southwesterly winds were recorded, at moderate to high speeds, together with temperatures of over 35 degrees C. The increase in airborne pollen detected, together with the large amount of particles collected, could have an adverse effect on health, particularly in pollen allergy sufferers, for whom dust-clouds represent an added risk.

Air Pollutants↗
PubMed2004

The nucleoprotein is required for efficient coronavirus genome replication.

The construction of a set of transmissible gastroenteritis coronavirus (TGEV)-derived replicons as bacterial artificial chromosomes is reported. These replicons were generated by sequential deletion of nonessential genes for virus replication, using a modified TGEV full-length cDNA clone containing unique restriction sites between each pair of consecutive genes. Efficient activity of TGEV replicons was associated with the presence of the nucleoprotein provided either in cis or in trans. TGEV replicons were functional in several cell lines, including the human cell line 293T, in which no or very low cytopathic effect was observed, and expressed high amounts of heterologous protein.

Base Sequence↗
PubMed2003

Meningeal carcinomatosis as the first manifestation of a transitional cell carcinoma of the bladder.

Meningeal carcinomatosis (MC) as first manifestation of a transitional cell carcinoma (TCC) of the bladder is rare. We report a 66-year-old man, smoker, who presented with two episodes of secondarily generalized partial motor seizures. The routine blood test, brain computed tomography (CT) scan, brain magnetic resonance imaging and electroencephalogram were normal. Cerebral spinal fluid (CSF) revealed a significant pleocytosis and a morphology compatible with non-differentiated non-small cell carcinoma. Broncofiberscopy, gastrofiberscopy, thoracicoabdominopelvic CT-scan and bone scintigraphy were normal but the urine cytology revealed malignant cells similar to those found in the CSF. TCC was diagnosed by cystoscopy and later necropsy confirmed the MC of this tumor. In this report we review the literature and analyze patient survival.

Aged↗