Biomedical subjects

R Martín

Publications and source records attributed to R Martín.

At least 19 recordsLinked to original sources

PubMed2005

Characterization of a reuterin-producing Lactobacillus coryniformis strain isolated from a goat's milk cheese.

Lactobacillus coryniformis CECT 5711, a strain isolated from a goat's milk cheese, displayed a broad-spectrum antimicrobial activity; as a consequence, its ability to produce the antagonistic compounds associated to lactic acid bacteria, including bacteriocins, hydrogen peroxide, lactic acid, acetic acid, and reuterin (3-hydroxypropionaldehyde, 3-HPA) was investigated. Production of bacteriocins or hydrogen peroxide by this strain could not be detected. However, in addition to lactic acid and acetic acid, it produced reuterin and cobalamin, a cofactor required for conversion of glycerol to 3-HPA through a glycerol dehydratase. The gene encoding a glycerol dehydratase subunit was detected by PCR and the corresponding amplicon was sequenced. This strain showed a high survival after exposition to conditions simulating those existing in the gastrointestinal tract as well as a notable ability to adhere to intestinal cells, which suggests that its reuterin-producing ability may be used for the host benefit. In addition, the strain showed a strong beta-galactosidase activity. Production of biogenic amines and degradation of mucin could not be detected.

Aldehydes↗

PubMed2005

Mercury and trace element fractionation in Almaden soils by application of different sequential extraction procedures.

A comparative evaluation of the mercury distribution in a soil sample from Almaden (Spain) has been performed by applying three different sequential extraction procedures, namely, modified BCR (three steps in sequence), Di Giulio-Ryan (four steps in sequence), and a specific SEP developed at CIEMAT (six steps in sequence). There were important differences in the mercury extraction results obtained by the three procedures according to the reagents applied and the sequence of their application. These findings highlight the difficulty of setting a universal SEP to obtain information on metal fractions of different mobility for any soil sample, as well as the requirement for knowledge about the mineralogical and chemical characteristics of the samples. The specific six-step CIEMAT sequential extraction procedure was applied to a soil profile (Ap, Ah, Bt1, and Bt2 horizons). The distribution of mercury and major, minor, and trace elements in the different fractions were determined. The results indicate that mercury is mainly released with 6 M HCl. The strong association of mercury with crystalline iron oxyhydroxides, present in all the horizons of the profile, and/or the solubility of some mercury compounds in such acid can explain this fact. Minor mercury is found in the fraction assigned to oxidizable matter and in the final insoluble residue (cinnabar).

Journal Article↗

PubMed2005

Application of polymerase chain reaction to detect adulteration of sheep's milk with goats' milk.

The polymerase chain reaction has been applied for the specific detection of goats' milk in sheep's milk using primers targeting the mitochondrial 12S ribosomal RNA gene. The use of goat-specific primers yielded a 122-bp fragment from goats' milk DNA, whereas no amplification signal was obtained in sheep's, cows', and water buffaloes' milk DNA. Polymerase chain reaction analysis of raw and heat-treated milk binary mixtures of sheep/goat enabled the specific detection of goats' milk with a sensitivity threshold of 0.1%. This study demonstrates the usefulness of the proposed polymerase chain reaction assay for authentication of milk products in routine analysis.

Animals↗

PubMed2005

[Cervical myelopathy: retrospective analysis of surgical results in 53 cases treated by anterior cervical discectomy and interbody fusion].

PATIENTS AND METHODS: We perform a retrospective analysis of clinical results in 53 consecutive patients surgically treated for cervical myelopathy or myelo-radiculopathy with anterior cervical discectomy and interbody fusion by means of the Cloward procedure. RESULTS: 64.2% of the patients had good outcome as measured by the improvement in one or more grades in the Nurick's scale. No mortality related to the surgical procedure was noted, although 9.4% of the cases suffered neurological deterioration. Correct fusion was achieved in 92.5% of the patients, with a rate of post-surgical kyphosis of 9.4%. Multivariate analysis identified as factors related to the clinical outcome: age (p = 0.008), vascular risk factors (p = 0.031), duration of symptoms (p = 0.002), pre-surgical neurological status (p < 0.001), neuroradiological diagnosis (p = 0.014), intra-medullary high signal intensity changes in T2-weighted images (p = 0.008), prolongation of the central somato-sensory or motor conduction times (p = 0.004) and neurologic complications (p = 0.012) CONCLUSIONS: Treatment optimisation of the patient suffering cervical spondylotic myelopathy requires individualised evaluation. Prospective randomised studies are needed to answer the questions when and how to operate.

Adult↗

PubMed2004

Rapid detection of cows' milk in sheeps' and goats' milk by a species-specific polymerase chain reaction technique.

A polymerase chain reaction (PCR) assay was developed for the specific identification of cows' milk in sheep's and goats' milk by using primers targeting the mitochondrial 12S rRNA gene. The use of a forward primer complementary to a conserved DNA sequence, along with a reverse primer specific for cow, yielded a 223-bp fragment from cows' milk DNA, whereas no amplification signal was obtained in sheep's and goats' milk DNA. The technique was applied to raw, pasteurized, and sterilized milk binary mixtures of cow-sheep and cow-goat, enabling the specific detection of cows' milk with a good sensitivity threshold (0.1%). The proposed PCR assay represents a rapid and straightforward method applicable to the authentication of milk and other dairy products in routine analysis.

Animals↗

PubMed2003

Differentiation of Enterococcus faecium from Lactobacillus delbrueckii subsp. bulgaricus and Streptococcus thermophilus strains by PCR and dot-blot hybridisation.

Variations in length and sequence of the 16S/23S spacer region of Enterococcus faecium provided the basis for development of simple PCR and dot-blot hybridisation assays that enabled the differentiation of potentially probiotic Enterococcus faecium strains from Lactobacillus delbrueckii subsp. bulgaricus and Streptococcus thermophilus. Such assays may be useful for differentiation of yoghurt starter cultures and enterococcal strains when they are simultaneously present in probiotic food products.

Adult↗

PubMed2003

[Gastrointestinal bleeding after endoscopic treatment of polypoid hamartoma (adenoma of Brunner's glands)].

The incidence of polypoidal tumors in the duodenum is scarce and Brunner's gland tumors represent 11% of these proliferations. Brunner's gland polypoid hamartoma or adenoma is a highly infrequent benign polypoid proliferation of Brunner's glands that is usually asymptomatic, although gastrointestinal bleeding or intestinal obstruction may sometimes occur. We present the case of a woman with an incidental diagnosis of duodenal polypoid hamartoma. The lesion was resected with polypectomy loop and at 48 h, the patient presented gastrointestinal bleeding as a complication. We describe the endoscopic treatment of the lesion and this complication.

Adult↗

PubMed2002

[HIV prevalence among homosexual and bisexual men in Spain, 1992-2000].

BACKGROUND: Our purpose was to describe the time trend in HIV seroprevalence among homo/ bisexual men. SUBJECTS AND METHOD: We analyzed 9,383 homo/ bisexual men who had a first voluntary test for HIV in 10 Spanish clinics from 1992 to 2000. RESULTS: HIV prevalence decreased from 20.3% in 1992 to 8.4% in 2000. In the multivariate analysis this decline appeared independently associated with the testing year and the birth cohort. CONCLUSIONS: New generations of voluntarily tested homo/bisexual men are less infected by HIV, but it is yet necessary to intensify the prevention programs.

Adolescent↗

PubMed2002

[Anterior cervical diskectomy and interbody arthrodesis using Cloward technique: retrospective study of complications and radiological results of 167 cases].

PATIENTS AND METHODS: We performed a retrospective analysis of complications and radiological results in 167 patients surgically treated, for discal or spondylotic disease of the cervical spine, with Cloward procedure. Using uni and multivariate analysis, we tried to identify risk factors that might be correlated with surgical complications or radiological results. RESULTS: Surgical treatment was indicated for cervical radiculopathy in 68% of the patients and for myelopathy or radiculomyelopathy in the remaining 32%. The pathologic disease responsible of the symptomatology was soft disk herniation in 59% of the cases and spondylotic changes in 41%. The patients that underwent surgery because of myelopathy were one decade older, had a longer symptomatic period and presented multi-segmentary spondylotic disease with higher frequency than patients affected of radiculopathy. The most common segments operated were CS-C6 (44.3%) and C6-C7 (30.5%). Surgical mortality was 0.6% and morbidity 29.3%. Most of the complications were transient, although 4.8% of the patients developed permanent neurological deterioration. CONCLUSIONS: Complications were most commonly seen in the group of the patients undergoing surgery because of long-lasting myelopathy with multi-segmentary spondylotic disease, in those with vascular risk factors and in those operated of more than one segment. Surgeon anatomic knowledge and experience are critical for diminishing such complications. Non-union rate was 9.6%, and another 9.6% of the patients developed post-surgical kyphosis. Both factors correlated with the need of re-operation.

Adult↗

PubMed2002

[Cauda equina meningioma in a girl: presentation of a case and review of the literature].

Meningiomas are unusual in childhood, and the intraspinal location is very uncommon. Those arising from lumbar dura matter are the most rare among spinal neoplasms of meningeal origin. We present the case of a 12-years-old girl with a cauda equina meningioma. As in previously reported cases, the initial complain was back pain with radicular irradiation. The girl had few neurological findings, with pyramidal signs of both lower limbs as single neurological impairment. She underwent surgical treatment through an open door laminoplasty and the tumour was completely removed without neurological deficit. After 2-year of follow-up she remains asymptomatic.

Back Pain↗

PubMed2002

Recurrent lentigo maligna as amelanotic lentigo maligna melanoma.

Amelanotic lentigo maligna and lentigo maligna melanoma are extremely rare tumours. Even rarer is a recurrent amelanotic lentigo maligna or amelanotic lentigo maligna melanoma at the site of a previously removed pigmented lentigo maligna. We describe two cases of recurrent amelanotic lentigo maligna melanoma manifesting as erythematous plaques evolved from previously excised pigmented lentigo maligna.

Aged↗

PubMed2001

Cadmium chloride-induced dysplastic changes in the ventral rat prostate: an immunohistochemical and quantitative study.

BACKGROUND: Cadmium chloride is an environmental toxic that might be implicated in human prostate carcinogenesis. The study was directed: 1) to evaluate the immunoexpression of markers for cell proliferation, apoptosis, and resistance to apoptosis, and 2) to estimate the size of premalignant cell population in the preneoplastic changes induced in ventral prostates of rats treated with cadmium chloride administered in drinking water. METHODS: The following parameters were calculated in the ventral prostatic lobe of normal rats and rats that received cadmium in drinking water during 18 months: total volume, epithelial volume, total number of epithelial cells, numerical density of epithelial cells, percentage of cells that immunostained to the proliferating cell nuclear antigen (PCNA), percentage of apoptotic cells (evaluated by a DNA fragmentation method), and absolute volume and volume fraction of immunostaining to bcl-2. RESULTS: The percentage of PCNA immunoreactive nuclei, the bcl-2 expression, and the numerical density of epithelial cells were significantly (P < 0.05) increased in the dysplastic prostatic acini of treated rats in comparison with the normal acini of treated rats and control animals. The percentage of apoptotic nuclei from ventral dysplastic acini was significantly (P < 0.05) decreased in comparison with that of normal acini. A negative correlation between proliferation and apoptosis was found in dysplastic lesions. CONCLUSIONS: Prostate epithelial dysplasia induced in rats by cadmium presents an increased proliferative activity and high expression of bcl-2 protein, as was described in human prostate intraepithelial neoplasia. However, the rate of apoptosis in rat dysplasia was importantly decreased, in contrast to that observed in some human preneoplastic changes. This decrease might be related to the increase of bcl-2 expression.

Administration, Oral↗

PubMed2001

Citrate, a possible precursor of astaxanthin in Phaffia rhodozyma: influence of varying levels of ammonium, phosphate and citrate in a chemically defined medium.

The influence of ammonium, phosphate and citrate on astaxanthin production by the yeast Phaffia rhodozyma was investigated. The astaxanthin content in cells and the final astaxanthin concentration increased upon reduction of ammonium from 61 mM to 12.9 mM (from 140 microg/g to 230 microg/g and 1.2 microg/ml to 2.3 microg/ml, respectively). Similarly, both the astaxanthin content and astaxanthin concentration increased by reducing phosphate from 4.8 mM to 0.65 mM (160 microg/g to 215 microg/g and 1.7 microg/ml to 2.4 microg/ml, respectively). Low concentrations of ammonium or phosphate also increased the fatty acid content in cells. By analogy with lipid synthesis in other oleaginous yeasts, an examination of the data for varying nitrogen and phosphate levels suggested that citrate could be the source of carbon for fatty acids and carotenoid synthesis. Supporting this possibility was the fact that supplementation of citrate in the medium at levels of 28 mM or higher notably increased the final pigment concentration and pigment content in cells. Increased carotenoid synthesis at low ammonium or phosphate levels, and stimulation by citrate were both paralleled by decreased protein synthesis. This suggested that restriction of protein synthesis could play an important role in carotenoid synthesis by P. rhodozyma.

Citric Acid↗

PubMed2001

Identification and characterisation of human xCT that co-expresses, with 4F2 heavy chain, the amino acid transport activity system xc-.

We have identified a new human complementary deoxyribonucleic acid (cDNA), for the xc- amino acid transporter (HGMW-approved name SLC7A11; also known as human xCT), that, when co-expressed with the heavy chain of surface antigen 4F2 (4F2hc, also termed CD98), but not with rBAT, (related to the bo,+ amino acid transporter), induces system xc- transport activity in Xenopus oocytes. Human xCT is the seventh human member of the family of amino acid transporters that are subunits of 4F2hc or rBAT and, inview of its amino acid sequence identity (89%) with mouse xCT, is most probably the human orthologue thereof. The amino acid transport activity induced by the co-expression of human 4F2hc and xCT in Xenopus oocytes was sodium independent and specific for L-cystine, L-glutamate and L-aspartate. This activity also functioned in an exchange mode (e.g. cystine/glutamate) with a substrate stoichiometry of 1:1. Expression of human xCT alone in oocytes did not induce amino acid transport activity and the expressed xCT protein was localised intracellularly. When human xCT was co-expressed with 4F2hc, the former localised to the oocyte plasma membrane. Tissue-expression studies showed that human SLC7A11 mRNA is expressed mainly in the brain, but also in pancreas and in cultured cell lines. The transport characteristics of human xCT and the distribution of its tissue expression strongly suggest that it corresponds to the human amino acid transporter system xc-.

Amino Acid Sequence↗

PubMed2001

PCR-SSCP: a simple method for the authentication of grouper (Epinephelus guaza), wreck fish (Polyprion americanus), and Nile perch (Lates niloticus) fillets.

A method of DNA analysis has been developed to verify the authenticity of grouper (Epinephelus guaza), wreck fish (Polyprion americanus), and Nile perch (Lates niloticus) fillets. A short fragment (208 bp) of the mitochondrial 12S rRNA gene was amplified by the polymerase chain reaction and analyzed by single-strand conformation polymorphism to get species-specific patterns of single-stranded DNA (ssDNA). DNA strands were separated by native polyacrylamide gel electrophoresis and visualized by silver staining. Discrimination among the three fish species studied was possible, because each one expressed a specific ssDNA pattern.

Animals↗

PubMed2001

Identification of goose (Anser anser) and mule duck (Anasplatyrhynchos x Cairina moschata) foie gras by multiplex polymerase chain reaction amplification of the 5S RDNA gene.

Polymerase chain reaction (PCR) amplification of the nuclear 5S rDNA gene has been used for the identification of goose and mule duck foie gras. Two species-specific reverse primers were designed and used in a multiplex reaction, together with a forward universal primer, to amplify specific fragments of the 5S rDNA in each species. The different sizes of the species-specific amplicons, separated by agarose gel electrophoresis, allowed clear identification of goose and mule duck foie gras samples. This genetic marker can be useful for detecting fraudulent substitution of the duck liver for the more expensive goose liver.

Animals↗

PubMed2001

Activation of defence-related genes during senescence: a correlation between gene expression and cellular damage.

The correlation between activation of defence-related gene expression and plant senescence was investigated by evaluating the presence of specific transcripts in various leaves of tobacco senescing plants. Expression of most genes examined was found to be induced shortly after flowering; however, each gene had its own characteristic timing of expression and level of RNA accumulation. Studies of the symptoms developed in senescing leaves responding to bacterial inoculation suggest that the accumulation of defence-related transcripts in these tissues might be related with the mechanism of senescence rather than with protection of the plant against pathogen infection. We observed that the high level of GUS expression directed by the beta-1,3-glucanase gn1 promoter, in senescing leaves of transgenic tobacco plants. decreased after bacterial inoculation, in correlation with the formation of symptoms. Reduction of gene expression was likely to be the reflection of the additional damage caused by the bacteria in the senescent tissues inoculated.

Gene Expression Regulation, Developmental↗

PubMed2001

In vitro activity of linezolid and 11 other antimicrobials against 566 clinical isolates and comparison between NCCLS microdilution and Etest methods.

The in vitro activity of linezolid and 11 other antimicrobials was determined for 566 clinical isolates of Staphylococcus aureus, Staphylococcus epidermidis, Enterococcus spp., Streptococcus pyogenes, Streptococcus agalactiae, Streptococcus pneumoniae, Haemophilus influenzae and Moraxella catarrhalis, some of them resistant to several antibiotics, using a broth microdilution method and the Etest method. All Gram-positive organisms tested were inhibited by a concentration of <or=4 mg/L of linezolid, including methicillin-resistant staphylococci, vancomycin- and ampicillin-resistant enterococci, and penicillin-intermediate and -resistant pneumococci. MICs of linezolid by the Etest method were usually one to two dilution values lower than those obtained by microdilution.

Acetamides↗