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Biomedical subjects

C Sánchez

Publications and source records attributed to C Sánchez.

At least 19 recordsLinked to original sources

A pilot clinical study of Delta9-tetrahydrocannabinol in patients with recurrent glioblastoma multiforme.

Delta(9)-Tetrahydrocannabinol (THC) and other cannabinoids inhibit tumour growth and angiogenesis in animal models, so their potential application as antitumoral drugs has been suggested. However, the antitumoral effect of cannabinoids has never been tested in humans. Here we report the first clinical study aimed at assessing cannabinoid antitumoral action, specifically a pilot phase I trial in which nine patients with recurrent glioblastoma multiforme were administered THC intratumoraly. The patients had previously failed standard therapy (surgery and radiotherapy) and had clear evidence of tumour progression. The primary end point of the study was to determine the safety of intracranial THC administration. We also evaluated THC action on the length of survival and various tumour-cell parameters. A dose escalation regimen for THC administration was assessed. Cannabinoid delivery was safe and could be achieved without overt psychoactive effects. Median survival of the cohort from the beginning of cannabinoid administration was 24 weeks (95% confidence interval: 15-33). Delta(9)-Tetrahydrocannabinol inhibited tumour-cell proliferation in vitro and decreased tumour-cell Ki67 immunostaining when administered to two patients. The fair safety profile of THC, together with its possible antiproliferative action on tumour cells reported here and in other studies, may set the basis for future trials aimed at evaluating the potential antitumoral activity of cannabinoids.

Adult↗

Growth of Pleurotus ostreatus on wheat straw and wheat-grain-based media: Biochemical aspects and preparation of mushroom inoculum.

Mycelial growth, intracellular activity of proteases, laccases and beta-1,3-glucanases, and cytoplasmic protein were evaluated in the vegetative phase of Pleurotus ostreatus grown on wheat straw and in wheat-grain-based media in Petri dishes and in bottles. The productivity of the wheat straw and wheat-grain-based spawn in cylindrical polyethylene bags containing 5 kg of chopped straw was also determined. We observed high activity of proteases and high content of intracellular protein in cultures grown on wheat straw. This suggests that the proteases are not secreted into the medium and that the protein is an important cellular reserve. On the contrary, cultures grown on wheat straw secreted laccases into the medium, which could be induced by this substrate. P. ostreatus grown on media prepared with a combination of wheat straw and wheat grain showed a high radial growth rate in Petri dishes and a high level of mycelial growth in bottles. The productivities of wheat straw and wheat-grain-based spawn were similar. Our results show that cheaper and more productive mushroom spawn can be prepared by developing the mycelium on wheat straw and wheat-grain-based substrates.

Agaricales↗

Plant regeneration through somatic embryogenesis from tissues of mature oak trees: true-to-type conformity of plantlets by RAPD analysis.

Somatic embryogenesis was induced in expanding leaf explants excised from epicormic shoots forced from branch segments taken at four different times of year from a mature oak (Quercus robur L.). Branch segments 2-4 cm in diameter produced most shoots when collected in March. Somatic embryos were induced on explants derived from branches of all collection dates, although collection in November seemed to afford the best results. Germination and conversion ability of embryos of embryogenic lines derived from six oak trees depended heavily on genotype, conversion rates ranging from 0 to 70%. RAPD analyses found no evidence of genetic variation either within or between the embryogenic lines established from three of these trees, or between these lines and the trees of origin, or between somatic embryo derived plantlets and the trees of origin. The embryogenic system used in this study appears to be suitable for true-to-type clonal propagation of mature oak genotypes.

Culture Media↗

Allele frequencies of the 15 AmpF/Str Identifiler loci in the population of Metztitlán (Estado de Hidalgo), México.

The 15 AmpF/STR Identifiler loci (D8S1179, D21S11, D7S820, CSF1PO, D3S1358, TH01, D13S317, D16S539, D2S1338, D19S433, vWA, TPOX, D18S51, D5S818 and FGA) were analyzed in the sample of 180 unrelated autochthonous healthy adults born in Meztitlán City from the valley of Metztitlán (Estado de Hidalgo, México). The agreement with Hardy-Weinberg equilibrium was confirmed for all loci. From the forensic point of view, the heterozygosity value, power of discrimination and the a priori chance of exclusion were calculated.

DNA Fingerprinting↗

The Bradyrhizobium japonicum napEDABC genes are controlled by the FixLJ-FixK(2)-NnrR regulatory cascade.

Nitrate respiration by the N(2)-fixing symbiotic bacteria Bradyrhizobium japonicum USDA110 is mediated by a Nap (periplasmic nitrate reductase) encoded by the napEDABC genes. Expression of a transcriptional fusion of the nap promoter region to the reporter gene lacZ, P(napE)-lacZ, was very low in aerobically grown cells of USDA110, but expression was induced approx. 3-fold when the cells were cultured under microaerobic conditions, and 12-fold when nitrate was added to the microaerobic incubation medium. The P(napE)-lacZ fusion was not expressed in the fixL 7403, fixJ 7360 and fixK(2) 9043 mutant strains. Microaerobic induction of the P(napE)-lacZ fusion was retained in the nnrR 8678 mutant, but no increase in beta-galactosidase activity was observed upon nitrate addition. Western-blot and Methyl Viologen-dependent nitrate reductase activity assays showed that synthesis and activity of the catalytic NapA subunit in USDA110 was similar to that in the napC 0906 and nirK GRK308 mutant strains incubated microaerobically with nitrate. These results suggest that nitrate and nitrite, which are not reduced by the napC 0906 and nirK GRK308 mutant cells respectively, induced the synthesis and activity of NapA; conversely, formation of endogenous NO was not required for induction of Nap expression.

Bacterial Proteins↗

[Impact of metabolic syndrome on CRP levels].

OBJECTIVE: C-reactive protein (CRP) is considered a marker of subclinical atherosclerosis. The aim of the study was to assess whether the metabolic syndrome (MS) and parameters involved in its diagnosis might influence serum CRP values. PATIENTS AND METHOD: Cross-sectional study in outpatients of a HTA and Vascular Risk clinic. MS was diagnosed according to National Cholesterol Educational Program ATP-III guidelines, and hs-CRP was analyzed by nephelometry. RESULTS: A total of 1,969 patients (47% male) were evaluated and distributed into four groups: 1) 1,220 non-diabetics without MS; 2) 384 non-diabetics with MS; 3) 153 diabetics without MS, and 4) 212 diabetics with MS. Patients with MS had higher CRP in both non-diabetic 3.0 (1.7-4.4) mg/l vs. 1.7 (0.9-3.4) mg/l; p=0.001 (MW), and diabetic patients: 2.8 (1.5-4.6) mg/l vs. 2.2 (0.9-4.3) mg/l; p=0.01 (MW). Diabetic patients without MS had CRP values not different to non-diabetic without MS. CRP values increased in relation to the number of parameters included in the MS from 1.7 (2.2) mg/l, in patients without any parameters, to 4.2 (2.8) mg/l in patients who fulfilled five parameters (p=0.001) (KW). In multiple regression analysis abdominal obesity (p=0.001), TG (p=0.001) and glucose (p=0.02) were associated with CRP levels after correcting for other factors. Abdominal obesity (OR: 1.9; 95% CI: 1.5-2.4; p=0.001) and TG (OR: 1.4; 95% CI: 1.1 -1.7; p=0.003), but not glucose were independent factors related to the presence of high levels of CRP (>3 mg/l) in a logistic regression analysis. CONCLUSIONS: Diabetic and non-diabetic patients with MS have high CRP levels. Of the five components of MS, the most closely related to CRP is abdominal obesity.

Abdomen↗

Fast and stable recording of birefringence and holographic gratings in an azo-polymethacrylate using a single nanosecond light pulse.

Pulsed light-induced recording in azobenzene polymers has recently been studied due to its potential use in optical storage applications. In this paper we study the photoinduced birefringence (Deltan) and holographic grating recording in an azobenzene side chain liquid-crystalline polymethacrylate irradiating with a single 4 ns light pulse at 532 nm. For some irradiation conditions, Deltan grows in less than 50 ns reaching an essentially stable value of about 10(-2). Holographic gratings have been registered using intensity and polarization patterns. Fast response and stability, similar to those of Deltan, was observed in the holographic recording process. Both light-induced anisotropy and relief contributions have been found in the case of gratings recorded using intensity patterns, relief being the dominant contribution at high recording energies. Polarization gratings have been recorded using two orthogonally circularly polarized beams. The resultant gratings showed stable efficiencies up to 0.8% (measured at 633 nm in 1-mum-thick films) and no measurable relief was observed.

Journal Article↗

Solid- and vapor-phase antimicrobial activities of six essential oils: susceptibility of selected foodborne bacterial and fungal strains.

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.

Anethum graveolens↗

Polarized light out-coupling from lightguides for LCDs.

New designs of lightguide systems, which emit linear polarized light with a high efficiency for transmissive and transflective LCD applications, are presented. These systems are equipped with nano- and/or micro-structured films or coatings, which emit highly collimated or diffuse linearly polarized light with a high efficiency. The films are based on polarization-selective scattering, reflection, or diffraction of light and their properties can be tuned to a large extent dependent on their envisioned application. For instance, edge-lit lightguide systems are discussed, which combine a range of desirable features such as a high transparency in direct view, a direct emission of light at normal angles to the plane of the lightguide, and a purely unidirectional out-coupling of light towards the LCD-side.

Journal Article↗

Differential patterns of constitutive intracellular laccases of the vegetative phase of Pleurotus species.

The constitutive intracellular laccase activity of ten strains of Pleurotus spp. was determined in vitro and by zymograms, using different substrates. Differences in the in vitro activities were observed between all the strains; however, zymogram patterns were only similar for strains within same species, independently of any of the three substrate (2,6-dimethoxyphenol, p-anisidine or o-tolidine) used. The differences observed in the number and positions of the isoforms in the gel suggest that laccase zymograms can be used to differentiate species of this organism.

Aniline Compounds↗

The Fang population of Equatorial Guinea characterised by 15 STR-PCR polymorphisms.

Allele frequencies for 15 STR loci (D8S1179, D21S11, D7S820, CSF1PO, D19S433, HUMVWA31A, HUMTPOX, D18S51, D3S1358, HUMTHO1, D13S317, D16S539, D2S1338, D5S818 and HUMFGA) were analysed in the Fang population of Bioko Island, Equatorial Guinea. No deviation from Hardy-Weinberg equilibrium was found for all loci. Statistical parameters demonstrated the forensic utility of the analysed systems.

DNA Fingerprinting↗

Comparison between Haemophilus parasuis infection in colostrums-deprived and sow-reared piglets.

The aim of this study was to compare the development of Glasser's disease in sow-reared and colostrum-deprived piglets. Ninety piglets from a commercial pig farm in Spain were used. The farm was positive for Haemophilus parasuis. Fifty-two pigs were sow-reared (SR) and 38 were colostrum-deprived (CD) piglets. The animals were intratracheally inoculated with H. parasuis serovar 5 and sacrificed at 1, 2 and 3 days post-infection. To assess the development of disease, antibody titers, clinical signs, pathological lesions, microbiological isolation and PCR amplification were compared between the groups. Inoculation of SR pigs did not cause clinical signs or lesions of Glasser's disease. In SR pigs, H. parasuis isolation and specific PCR amplification from tissues showed a very low number of positive samples. In contrast, in CD pigs, inoculation resulted in the typical signs and lesions of Glasser's disease. Positive microbiological isolation and specific PCR products were obtained from the majority of the tissues tested, and no antibodies against H. parasuis were detected. The experimental infection using CD pigs describes a successful method to study this microorganism and confirms the important role that maternal antibodies play in protection against clinical signs and disease.

Animal Husbandry↗

Characterisation of three Amerindian populations from Hidalgo State (Mexico) by 15 STR-PCR polymorphisms.

The purpose of this study is to report allele frequency data of three ethnic Amerindian population samples: the Otomi (Hna-hnu) from eastern Sierra Madre and Ixmiquilpan valley and the Huasteco from La Huasteca. These groups were characterised by 15 STR-PCR polymorphisms (HumTH01, HumvWA, D18S51, HumTPOX, D19S433, D16S539, D13S317, D8S1179, D7S820, D5S818, HumFGA, CSF1PO, D2S1338, D3S1358 and D21S11). No significant deviations in observed allelic frequencies from Hardy-Weinberg equilibrium were found for all the studied systems. From the forensic point of view, the heterozygosity value, power of discrimination and the a priori chance of exclusion were calculated.

DNA Fingerprinting↗

Selectivity of (3)H-MADAM binding to 5-hydroxytryptamine transporters in vitro and in vivo in mice; correlation with behavioural effects.

1. Binding of the novel radioligand (3)H-2-(2-dimethylaminomethyl-phenylsulphanyl)-5-methyl-phenylamine ((3)H-MADAM) to the serotonin transporter (SERT) was used to characterise a range of selective serotonin re-uptake inhibitors (SSRIs) in vitro and in vivo. 2. (3)H-MADAM bound with high affinity in a saturable manner to both human SERT expressed in CHO cells (K(d)=0.20 nm (pK(d)=9.74+/-0.12), B(max)=35+/-4 fmol mg(-1) protein) and mouse cerebral cortex membranes (K(d)=0.21 nm (pK(d)=9.66+/-0.10), B(max)=50+/-24 fmol mg(-1) protein). 3. Binding of (3)H-MADAM was highly selective for SERT in vitro as demonstrated by the in vitro profile of MADAM tested at 75 different receptors, ion channels and transporters. This was further substantiated by the pharmacological profile of the binding. Hence, the binding of (3)H-MADAM was potently inhibited by SSRIs but not by selective inhibitors of noradrenaline transport and dopamine transport. Likewise, a 5-HT(2A/2C) receptor antagonist did not inhibit (3)H-MADAM binding. 4. (3)H-MADAM binding in vivo was inhibited only by compounds which also inhibited the binding of (3)H-MADAM in vitro (the SSRIs, mixed SERT/noradrenaline transport inhibitors and clomipramine), confirming the selectivity of (3)H-MADAM for SERT also in vivo. Moreover, compounds effective in inhibiting (3)H-MADAM binding were the only ones found to be active in the mouse 5-HTP potentiation test confirming the model as a behavioural correlate to in vivo 5-HT uptake. 5. Finally, it was found that a SERT occupancy of 85-95% was necessary to produce 50% of the maximum behavioural response (ED(50)).

5-Hydroxytryptophan↗