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Biomedical subjects

R Sanz

Publications and source records attributed to R Sanz.

At least 19 recordsLinked to original sources
PubMed2006

Microvascular perfusion 1 week and 6 months after myocardial infarction by first-pass perfusion cardiovascular magnetic resonance imaging.

OBJECTIVE: To characterise the evolution of myocardial perfusion during the first 6 months after myocardial infarction by first-pass perfusion cardiovascular magnetic resonance imaging (CMR) and determine its significance. DESIGN: Prospective cohort design. SETTING: Single-centre study in a teaching hospital in Spain. PATIENTS: 40 patients with a first ST-elevation myocardial infarction, single-vessel disease and thrombolysis in myocardial infarction (TIMI) grade 3 flow (stent in 33 patients) underwent rest and low-dose dobutamine CMR 7 (SD 1) and 184 (SD 11) days after infarction. Microvascular perfusion was assessed at rest by visual assessment and quantitative analysis of first-pass perfusion CMR. Of the 640 segments, 290 segments subtended by the infarct-related artery (IRA) were focused on. RESULTS: Both 1 week and 6 months after infarction, segments with normal perfusion showed more wall thickening, contractile reserve and wall thickness, and less transmural necrosis, p <0.05 in all cases. Of 76 hypoperfused segments at the first week, 47 (62%) normalised perfusion at the sixth month. However, 42 segments (14% of the whole group) showed chronic abnormal perfusion; these segments showed worse CMR indices in the late phase (p<0.05 in all cases). CONCLUSIONS: In patients with an open IRA, more than half of the segments with abnormal perfusion at the first week are normally perfused after six months. First-pass perfusion CMR shows that in a small percentage of segments, abnormal perfusion may become a chronic phenomenon-these areas have a more severe deterioration of systolic function, wall thickness, contractile reserve and the transmural extent of necrosis.

Cohort Studies↗
PubMed2006

Central role of supporting cells in cochlear homeostasis and pathology.

HYPOTHESIS: Supporting cells have a crucial role in degenerative and regenerative events of primary sensorial hair cells of the organ of Corti. This new role should determine future studies about pathophysiology of hearing loss and its regenerative treatment. SUPPORTING EVIDENCE: Recent findings suggest an active role of supporting cells in the maintenance of hair cell function and structure. Evidences of high energy consumption and close proximity to auditory nervous fibers suggesting K+ active exchange, preferential expression of specific proteins and antigens, presence of glucocorticoids receptors, affinity for cisplatin and regenerative potential give the supporting cells an important role in homeostasis of the organ of Corti and in some specific diseases affecting this structure. CONCLUSION: As well as glial cells provide protection and regeneration to neural tissues, supporting cells may provide the necessary metabolic and electrolitic conditions for hair cells mechanical and bioelectrical function. This opens new possibilities for the treatment of apparently "irreversible" destruction of the inner ear.

Animals↗
PubMed2006

[Varicella-zoster infection with isolated cochleovestibular affectation (without facial palsy)].

Otological complications of Ramsay Hunt syndrome include facial paralysis, tinnitus, hearing loss, vertigo, dysgeusia, and skin eruption. The lower cranial nerves sometimes are affected by this neuritis. A case is reported of a man without immune-system impairment who had a cranial mononeuritis with unilateral involment of the VIII and VII cranial nerves after infection with varicella-zoster without herpetic lesions.

Audiometry, Pure-Tone↗
PubMed2006

Endonasal endoscopic management of a large meningocephalocele in a patient with concomitant middle skull base defect.

The presence of a skull base defect can lead to major complications such as cerebrospinal fluid leak, meningocele, encephalocele and meningitis. It is exceptional to find the existence of two concomitant defects in the skull base. We present the case of a patient with concomitant spontaneous defects of the anterior and middle skull base that were surgically repaired. After 18 years of right rhinorrhea the patient was referred after being diagnosed with a large right nasal fossa meningoencephalocele, which was surgically removed by functional endoscopic sinus surgery. Following the surgery the patient complained about unilateral ear fullness. A paracentesis revealed a highly suspicious cerebrospinal fluid collection. High resolution scans revealed a defect in the mastoid tegmen; subsequently a transmastoid approach was carried out. Greater defects or those lying around the internal auditory canal, are best treated via the middle fossa approach. In the anterior cranial fossa the treatment of choice is provided by endoscopic procedures, but frontal bone craniotomy should be considered if the defect is in the frontal sinus or greater than 5 cm in size.

Cerebrospinal Fluid Rhinorrhea↗
PubMed2005

New approach for the refinement of the location of the X-chromosome breakpoint in a previously described female patient with choroideremia carrying a X;4 translocation.

Choroideremia (CHM) is an X-linked recessive ophthalmic disease characterized by a progressive degeneration of the choroid and the pigmented epithelium of the retina. We present the genetic characterization of a female patient affected with CHM who has been previously studied cytogenetically and showed a balanced translocation between chromosomes X and 4 [46,X,t(X;4)(q21;p16)]. The breakpoint in the X chromosome lies in the locus of CHM gene and for this reason, we have elucidated whether or not CHM was disrupted in the X chromosome involved in the translocation using different techniques. FISH showed that the 3'UTR and the last exons of the CHM were on the der(X) chromosome, and the 5'UTR and first exons of this gene were on the der(4) chromosome. Expression level analysis revealed that the breakpoint in the der(X) was located between exons 8 and 9 of the CHM gene because the expression level decreased from this point onwards. Based on this result the expression level analysis proved to be a valid method to pinpoint the location of breakpoints when the gene being expressed in peripheral blood is disrupted. Our results confirmed that the CHM gene was indeed disrupted in the X chromosome involved in the translocation. Besides, the nonrandom inactivation of the normal X chromosome observed using a methylation-specific polymerase chain reaction (M-PCR) technique explained the CHM in the female patient.

3' Untranslated Regions↗
PubMed2003

Sonication effect on cellular material in sedimentation and gravitational field flow fractionation.

Sonication procedures are generally used prior to field flow fractionation (FFF) separation in order to produce suspensions without aggregates. Yeast cells manufactured in active dry wine yeast (ADWY) were placed in an ultrasound water bath in order to disrupt possible clumps and to obtain a single-cell suspension to be used in optimal conditions during fermentation processes. In order to determine whether this sample preparation procedure meets absolute needs, different yeast samples before and after sonication were analysed by two field flow fractionation techniques. It is shown that 2 min of sonication in the sample preparation process is sufficient to obtain an optimal dispersion of the yeast cells, that is, without critical percentage of aggregates. To demonstrate this effect, photographs of the yeast cell suspensions were performed with non-sonicated and sonicated yeast sample dispersion. The resulting data are compared with the elution profiles obtained from the two different FFF techniques. It is demonstrated that fractogram profiles prove the effectiveness of sonication methodologies.

Fractionation, Field Flow↗
PubMed2002

Improved performance of gravitational field-flow fractionation for screening wine-making yeast varieties.

Performance of gravitational field-flow fractionation (GFFF) is improved here with respect to the ability to fractionate and distinguish different varieties of wine-making yeast from Saccharomyces cerevisiae. A new GFFF channel with non-polar walls has been employed to enhance fractionation selectivity and reproducibility. Since GFFF retention depends from first principles on particle size, Coulter counter measurements were performed in order to compare size distribution profiles with GFFF profiles. From such a comparison, GFFF was shown to be able to reveal differences in yeast cells other than size. This could make use of GFFF for screening different varieties of wine-making yeast towards future quality assessment procedures based on a possible correlation between yeast cell morphology indexes and quality indexes.

Fractionation, Field Flow↗
PubMed2002

Aniridia as part of a WAGR syndrome in a girl whose brother presented hypospadias.

Aniridia can arise as part of the WAGR syndrome (Wilms tumour. aniridia, genitourinary anomalies, and mental retardation), due to a deletion or chromosomal region 11p13. We report a girl with a complete WAGR syndrome, whose brother presented hypospadias. Cytogenetic, FISH and molecular studies showed a deletion in one chromosome 11 of the patient. No cytogenetic rearrangement or deletion affecting the genes included in this region (PAX6 and WT1) were observed in her brother and parents. This excludes a higher risk than that of the general population for developing Wilms tumour in the brother and supports that the presence of WAGR syndrome in the patient and hypospadias in her brother is a chance association. We conclude that the identification and definition of the deletions in the WAGR region, which include the WT1 locus are important in order to identify a high tumour risk in infant patients with aniridia including those without other WAGR anomalies.

Aniridia↗
PubMed2001

Synthesis of functionalized pyrrole and indole derivatives through carbometallation of lithiated double bonds.

Bis(2-lithioallyl)amines derived from bis(2-bromoallyl)amines undergo intramolecular carbometallation of a lithiated double bond, giving dilithiated dihydropyrroles. The cyclizations are promoted by N,N,N',N'-tetramethylethylenediamine (TMEDA). Reaction of these intermediates with electrophiles allows the preparation of some new fused and nonfused five-membered functionalized heterocycles. Although 2-lithioallylamines do not suffer intermolecular carbometallation, dimerization products are obtained with their copper or zirconium derivatives. Finally, the application of this new reaction to 2-lithio-N-(2-lithioallyl)anilines leads to 3-lithiomethylindole derivatives, which are transformed to functionalized indole derivatives by reaction with electrophiles.

Journal Article↗
PubMed2001

Gravitational field-flow fractionation for the characterisation of active dry wine yeast.

Gravitational field-flow fractionation (GrFFF) is applied to the fractionation of active dry wine yeast. An experimental approach to the analysis of the effects that field variation by changing mobile phase composition and flow-rate have on the fractionation process of standard particles (polystyrene) was first developed to further obtain effective fractionation of wine yeast by GrFFF. Scanning electron microscopy and Coulter counter particle size measurements were used to monitor the fractionation extent and capabilities of GrFFF to describe the distribution of yeast cells populations.

Chemical Fractionation↗
PubMed2001

The molecular basis of 3-methylcrotonylglycinuria, a disorder of leucine catabolism.

3-Methylcrotonylglycinuria is an inborn error of leucine catabolism and has a recessive pattern of inheritance that results from the deficiency of 3-methylcrotonyl-CoA carboxylase (MCC). The introduction of tandem mass spectrometry in newborn screening has revealed an unexpectedly high incidence of this disorder, which, in certain areas, appears to be the most frequent organic aciduria. MCC, an heteromeric enzyme consisting of alpha (biotin-containing) and beta subunits, is the only one of the four biotin-dependent carboxylases known in humans that has genes that have not yet been characterized, precluding molecular studies of this disease. Here we report the characterization, at the genomic level and at the cDNA level, of both the MCCA gene and the MCCB gene, encoding the MCC alpha and MCC beta subunits, respectively. The 19-exon MCCA gene maps to 3q25-27 and encodes a 725-residue protein with a biotin attachment site; the 17-exon MCCB gene maps to 5q12-q13 and encodes a 563-residue polypeptide. We show that disease-causing mutations can be classified into two complementation groups, denoted "CGA" and "CGB." We detected two MCCA missense mutations in CGA patients, one of which leads to absence of biotinylated MCC alpha. Two MCCB missense mutations and one splicing defect mutation leading to early MCC beta truncation were found in CGB patients. A fourth MCCB mutation also leading to early MCC beta truncation was found in two nonclassified patients. A fungal model carrying an mccA null allele has been constructed and was used to demonstrate, in vivo, the involvement of MCC in leucine catabolism. These results establish that 3-methylcrotonylglycinuria results from loss-of-function mutations in the genes encoding the alpha and beta subunits of MCC and complete the genetic characterization of the four human biotin-dependent carboxylases.

Adult↗
PubMed2001

Prenatal diagnosis on fetal cells from maternal blood: practical comparative evaluation of the first and second trimesters.

Objectives- Several attempts have been made to determine the gestational period in which the maximum number of fetal cells can be found in maternal blood and consequently which is the best week in which to perform a reliable non-invasive prenatal diagnosis. Most studies conclude that the number of nucleated red blood cells (NRBC) increases in line with gestation, but the number of cells that are fetal in origin (FNRBC) decreases in the third trimester. The aim of the present study was to make a practical comparative evaluation of the first and second trimesters to ascertain the period in which a greater number of FNRBC can be found of the total number of NRBC identified. Methods- Double density gradient and a posterior positive selection (CD71) by magnetic activated cell sorting (MACS) were employed. In the final fraction, erythroblasts were identified using Kleihauer staining and were studied using the fluorescence in situ hybridization (FISH) interphasic technique. Results- There was a significant difference (p<0.05) between the mean number of FNRBC found in the first and second trimesters. Conclusions- The number of FNRBC increases from the first to the second trimester. It appears that the optimum week in which to perform a reliable non-invasive prenatal diagnosis is around the 15th week.

Adult↗
PubMed2001

Association between intimin (eae) and EspB gene subtypes in attaching and effacing Escherichia coli strains isolated from diarrhoeic lambs and goat kids.

Attaching and effacing Escherichia coli (AEEC) strains isolated from diarrhoeic lambs and goat kids were characterized for intimin (eae) and EspB (espB) gene subtypes by PCR and sequencing, and for genetic relatedness by PFGE. Fifty (23 ovine and 27 caprine) AEEC strains of 398 (246 ovine and 152 caprine) analysed were detected by colony blot hybridization. These strains were epidemiologically unrelated since they were isolated from different outbreaks of neonatal diarrhoea over a long period. Ovine AEEC strains belonged to serogroups O2, O4, O26, O80, O91 or were untypable, and caprine strains belonged to serogroups O3, O153 and O163. Two intimin subtypes were detected among the ovine and caprine strains studied. Most of the strains (43/50) had the beta type intimin gene, but seven ovine strains possessed a variant gamma type intimin gene (gamma(V)). Analysis of deduced amino acid sequences of the eae gene revealed that the sequences of beta intimin of ovine and caprine strains were virtually identical to those of beta intimin of rabbit EPEC, human EPEC clone 2 and swine AEEC, whereas the gamma(V) intimin present in seven ovine strains had 75-76% identity with gamma intimin of human EHEC clone 1 strains, and 96% of identity with intimin of the human EHEC strain 95NR1 of serotype O111:H-. A PCR test was developed to identify the three different espB gene subtypes, espB of human EPEC clone 1 (espBalpha), espB of human EHEC clone 1 (espBgamma) and espB of rabbit EPEC and human EPEC clone 2 (espBbeta). There was close correlation between the intimin beta type and the espBbeta gene subtype in the ovine and caprine AEEC strains. The seven ovine strains possessing the gamma(V) intimin gene possessed the espBalpha gene subtype. None of the strains studied possessed the espBgamma gene found in human O157:H7 EHEC strains. PFGE analysis of genomic DNA of selected strains showed a great diversity among strains. Cluster analysis of PFGE patterns showed greater divergence between strains with the gamma(V) intimin gene than between strains with the beta intimin gene. This study showed that most of the AEEC strains isolated from diarrhoeic lambs and goat kids possessed beta intimin and espB genes identical to those of rabbit EPEC, and they may be associated with enteric disease in small ruminants.

Adhesins, Bacterial↗
PubMed2001

A maternal inherited translocation t(1;22)(q11;p11) in two infertile brothers.

We report two infertile brothers presenting with azoospermia and oligozoospermia. Cytogenetic studies using G-banding and FISH analysis on lymphocyte cultures revealed an autosomal balanced reciprocal translocation t(1;22)(q11;p11) in both males. The same translocation was found in their mother, but not in a third fertile brother and maternal uncle suggesting that this translocation might compromise the male but not the female gametogenesis in this family.

Adult↗
PubMed2000

Cryptic 6q subtelomeric deletion associated with a paracentric inversion in a mildly retarded child.

We report on a girl with minor anomalies and developmental delay carrying an apparently balanced paracentric inversion of chromosome 6q (q22qter). Fluorescent in situ hybridization analysis demonstrated a deletion of the subtelomeric region of 6q. This illustrates the use of specific subtelomeric fluorescent in situ hybridization probes to detect cryptic deletions as an important cause of mental retardation in seemingly balanced chromosome rearrangements.

Chromosome Deletion↗
PubMed2000

Rapid identification of a small dicentric supernumerary marker derived from chromosome 16 with a modified FISH technique on amniotic fluid.

Small supernumerary marker chromosomes are seldom found in prenatal diagnosis and the majority of them are difficult to identify. The only possibility to give a more precise prognosis is by establishing its origin. FISH is the best technique to identify the chromosomal origin, but in the majority of cases large amounts of chromosomal material are needed and this is time consuming. We have used a modification of the FISH technique that allows the hybridization of several probes on one slide. Using this method, we have identified the first de novo mosaic dicentric supernumerary marker derived from chromosome 16 (smaller than chromosome 21) in amniotic fluid. The gestation and the follow-up of the baby were normal.

Adult↗