Nanodisc-embedded cytochrome P450 P3A4 binds diverse ligands by distributing conformational dynamics to its flexible elements.

Cytochrome P450 3A4 (CYP3A4) metabolizes a wide range of drugs and toxins. Interactions of CYP3A4 with ligands are difficult to predict due to promiscuity and conformational flexibility. To better understand CYP3A4 conformational responses to ligands we use hydrogen deuterium exchange mass spectrometry (HDX-MS) to investigate the effect of ligands on nanodisc-embedded CYP3A4.

Reversibility and Low Commitment to Forward Catalysis in the Conjugation of Lipid Alkenals by Glutathione Transferase A4-4.

High concentrations of electrophilic lipid alkenals formed during oxidative stress are implicated in cytotoxicity and disease. However, low concentrations of alkenals are required to induce antioxidative stress responses. An established clearance pathway for lipid alkenals includes conjugation to glutathione (GSH) via Michael addition, which is catalyzed mainly by glutathione transferase isoform A4 (GSTA4-4).

Dynamics and Mechanism of Binding of Androstenedione to Membrane-Associated Aromatase.

Aromatase (CYP19A1) catalyzes the synthesis of estrogens from androgens and is an invaluable target of pharmacotherapy for estrogen-dependent cancers. CYP19A1 is also one of the most primordial human CYPs and, to the extent that its fundamental dynamics are conserved, is highly relevant to understanding those of the more recently evolved and promiscuous enzymes. A complementary approach employing molecular dynamics simulations and hydrogen-deuterium exchange mass spectrometry (HDX-MS) was employed to interrogate the changes in CYP19A1 dynamics coupled to binding androstenedione (ASD).

Identification and control of a multiplace hyperbaric chamber.

This work presents the automation of a multiplace hyperbaric chamber. It includes the system modeling, identification, controller calculation and system validation. With the proposed approach a good pressure profile tracking and repeatability are achieved.

Expression and Functional Characterization of Breast Cancer-Associated Cytochrome P450 4Z1 in .

CYP4Z1 is an "orphan" cytochrome P450 (P450) enzyme that has provoked interest because of its hypothesized role in breast cancer through formation of the signaling molecule 20-hydroxyeicosatetraenoic acid (20-HETE). We expressed human CYP4Z1 in and evaluated its catalytic capabilities toward arachidonic and lauric acids (AA and LA). Specific and sensitive mass spectrometry assays enabled discrimination of the regioselectivity of hydroxylation of these two fatty acids.

Membrane Fluidity Modulates Thermal Stability and Ligand Binding of Cytochrome P4503A4 in Lipid Nanodiscs.

Cytochrome P4503A4 (CYP3A4) is a peripheral membrane protein that plays a major role in enzymatic detoxification of many drugs and toxins. CYP3A4 has an integral membrane N-terminal helix and a localized patch comprised of the G' and F' helix regions that are embedded in the membrane, but the effects of membrane composition on CYP3A4 function are unknown. Here, circular dichroism and differential scanning calorimetry were used to compare the stability of CYP3A4 in lipid bilayer nanodiscs with varying ratios of 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphocholine to 1,2-dimyristoyl-sn-glycero-3-phosphocholine (DMPC).

MHC class I molecules act as tumor suppressor genes regulating the cell cycle gene expression, invasion and intrinsic tumorigenicity of melanoma cells.

The alteration of MHC class I (MHC-I) expression is a frequent event during cancer progression, allowing tumor cells to evade the immune system. We report that the loss of one major histocompatibility complex haplotype in human melanoma cells not only allowed them to evade immunosurveillance but also increased their intrinsic oncogenic potential. A second successive defect in MHC-I expression, MHC-I total downregulation, gave rise to melanoma cells that were more oncogenic per se in vivo and showed a higher proliferation rate and greater migratory and invasive potential in vitro.

Catalase-like activity of bovine met-hemoglobin: interaction with the pseudo-catalytic peroxidation of anthracene traces in aqueous medium.

Hemoglobin is a member of the hemoprotein superfamily whose main role is to transport O(2) in vertebrate organisms. It has two known promiscuous enzymatic activities, peroxidase and oxygenase. Here we show for the first time that bovine hemoglobin also presents a catalase-like activity characterized by a V(max )of 344 microM/min, a K(M )of 24 mM and a k(cat) equal to 115/min.

Total loss of HLA class I expression on a melanoma cell line after growth in nude mice in absence of autologous antitumor immune response.

Loss of HLA class I expression on tumor cells is a frequent event as an immune escape mechanism. Seven different altered HLA phenotypes have been defined in tumors. Various molecular mechanisms have been described as responsible for HLA class I loss.

Genetic diversity and the reproductive system in related species of antirrhinum.

Background And Aims: Seven related species of Antirrhinum (A. siculum, A. majus, A.

LOH at 6p21.3 region and HLA class I altered phenotypes in bladder carcinomas.

Alterations in HLA class I antigen expression have been frequently described in different epithelial tumors and are thought to favor tumor immune escape from T lymphocyte recognition. Multiple molecular mechanisms are responsible for these altered HLA class I tumor phenotypes. Some are structural defects that produce unresponsiveness to treatment with interferons.

A new extract of the plant Calendula officinalis produces a dual in vitro effect: cytotoxic anti-tumor activity and lymphocyte activation.

Background: Phytopharmacological studies of different Calendula extracts have shown anti-inflammatory, anti-viral and anti-genotoxic properties of therapeutic interest. In this study, we evaluated the in vitro cytotoxic anti-tumor and immunomodulatory activities and in vivo anti-tumor effect of Laser Activated Calendula Extract (LACE), a novel extract of the plant Calendula Officinalis (Asteraceae).

Methods: An aqueous extract of Calendula Officinalis was obtained by a novel extraction method in order to measure its anti-tumor and immunomodulatory activities in vitro.

Human leukocyte antigen-DQB1 and -DRB1 associations in patients with idiopathic sudden sensorineural hearing loss from a defined population of Northwest Spain.

Conclusion: The results of this study support the assertion that Southern European individuals have a genetically mediated predisposition to develop idiopathic sudden sensorineural hearing loss (SNHL).

Objective: To assess the influence of human leukocyte antigen (HLA)-DQB1 and -DRB1 alleles on the susceptibility to and the severity of idiopathic sudden SNHL.

Material And Methods: A prospective study of patients diagnosed with idiopathic sudden SNHL between October 2000 and September 2002 was conducted.

Association of a functional inducible nitric oxide synthase promoter variant with susceptibility to biopsy-proven giant cell arteritis.

Objective: To assess the contribution of 2 polymorphisms within the inducible nitric oxide (NOS2A) promoter region to susceptibility to giant cell arteritis (GCA).

Methods: One hundred three patients with biopsy-proven GCA and 198 ethnically matched controls from the Lugo region (Northwest Spain) were studied. Patients and controls were genotyped using polymerase chain reaction techniques for a multiallelic (CCTTT)n and for the TAAA repeat polymorphism in the promoter region of the NOS2A gene.

Analysis of a GT microsatellite in the promoter of the foxp3/scurfin gene in autoimmune diseases.

The aim of this study was to assess the possible association of the functional (GT)(n) microsatellite polymorphism in the FOXP3 gene with predisposition to several autoimmune diseases such as systemic lupus erythematosus (SLE), rheumatoid arthritis (RA), ulcerative colitis (UC), Crohn's disease, and celiac disease. We analyzed a case-control cohort composed of 231 SLE patients, 293 RA patients, 528 inflammatory bowel disease (354 Crohn's disease patients and 260 UC patients) patients, 103 celiac disease patients, and 274 healthy controls ethnically matched. Genotyping of (GT)(n) microsatellite was performed by polymerase chain reaction (PCR)-based method combined with fluorescent technology.

Interleukin 12 (IL12B) and interleukin 12 receptor (IL12RB1) gene polymorphisms in rheumatoid arthritis.

The aim of this study was to assess the possible association between the IL12B and the IL12RB1 gene polymorphisms and the systemic autoimmune disease rheumatoid arthritis (RA). Our study population consisted of 545 patients with RA and 393 healthy subjects. All the individuals were of white Spanish origin.

Interleukin 12 (IL12B), interleukin 12 receptor (IL12RB1) and interleukin 23 (IL23A) gene polymorphism in systemic lupus erythematosus.

Objective: The aim of this study was to assess the possible association between the interleukin-12B (IL12B) and interleukin-12 receptor beta 1 (IL12RB1) gene polymorphisms with systemic lupus erythematosus (SLE). In addition, we have undertaken a systematic search for genetic variants of interleukin 23 (IL23A).

Methods: The study was conducted on 559 SLE patients and 603 ethnically matched healthy controls.

Inducible nitric oxide synthase polymorphism is associated with susceptibility to Henoch-Schönlein purpura in northwestern Spain.

Objective: To assess the contribution of 2 polymorphisms within the inducible nitric oxide (NOS2A) promoter region to the susceptibility to Henoch-Schönlein purpura (HSP), and to determine if implications exist with severe systemic complications of HSP, in particular with severe renal involvement and permanent renal dysfunction (renal sequelae).

Methods: Fifty-eight patients from Northwest Spain with primary cutaneous vasculitis classified as HSP were studied. All patients were required to have had at least 2 years' followup.

A functional polymorphism of the NFKB1 promoter is not associated with ulcerative colitis in a Spanish population.

Background: This study investigated the influence of the NFKB1-94ins/delATTG in the susceptibility/phenotype to ulcerative colitis.

Methods: We analyzed the distribution of -94ins/delATTG NFKB1 in 258 patients and 264 healthy controls from southern Spain by a polymerase chain reaction-fluorescent method.

Results: The genotype and allele frequencies of -94ins/delATTG did not significantly differ between patients and controls.

Analysis of the functional NFKB1 promoter polymorphism in rheumatoid arthritis and systemic lupus erythematosus.

Nuclear factor (NF)-kappaB plays an important role in inflammatory diseases such as rheumatoid arthritis (RA) and systemic lupus erythematosus (SLE). A functional insertion/deletion polymorphism (-94ins/delATTG) has been identified in the promoter of the NFKB1 gene. In addition, a polymorphic dinucleotide repeat (CA) has been identified in proximity to the coding region of the human NFKB1 gene.

Systemic lupus erythematosus in southern Spain: a comparative clinical and genetic study between Caucasian and Gypsy patients.

We evaluated the influence of the hereditary make-up on the development of systemic lupus erythematosus (SLE) in two ethnic groups [Gypsy and white Caucasian Mediterranean (WCM) populations], living in the same geographic area. We compared 81 WCM and 25 Gypsy patients with SLE. The control group consisted of 185 healthy unrelated individuals, 105 WC and 80 Gypsies.

Allozymic differentiation of the Antirrhinum majus and A. siculum species groups.

Background And Aims: Fifty-two populations were sampled in order to establish the taxonomic delimitation and relationships of eight taxa belonging to the A. majus L. and A.

High frequency of homozygosity of the HLA region in melanoma cell lines reveals a pattern compatible with extensive loss of heterozygosity.

Malignant transformation of cells is frequently associated with abnormalities in human leukocyte antigen (HLA) expression. MHC class I loss or down-regulation in cancer cells is a major immune escape route used by a large variety of human tumours to evade antitumour immune responses mediated by cytotoxic T lymphocytes. The goal of our study was to explore HLA genotyping and phenotyping in a variety of melanoma tumour cell lines.

Distribution of HLA class I altered phenotypes in colorectal carcinomas: high frequency of HLA haplotype loss associated with loss of heterozygosity in chromosome region 6p21.

HLA class I loss or down-regulation is a widespread mechanism used by tumor cells to avoid tumor recognition by cytotoxic T lymphocytes, and thus favor tumor immune escape. Multiple mechanisms are responsible for these HLA class I alterations. In different epithelial tumors, loss of heterozygosity (LOH) at chromosome region 6p21.

A functional variant of IFNgamma gene is associated with coeliac disease.

In coeliac disease (CD) a profile of proinflammatory cytokines are secreted interferon gamma (IFNgamma) being one of the most important. A dinucleotide polymorphism consisting of a variable number of CA repeats related with IFNgamma production levels, has been reported on the first intron of the IFNgamma gene. The aim of this study was to analyse the influence of the functional IFNgamma CA repeats in CD predisposition through familial and case-control studies.