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PubMed2001

[Study on the muscarinic receptor and its subtypes in patients with chronic obstructive pulmonary disease].

OBJECTIVE: To investigate the M receptor and its subtypes in the lung tissue of patients with chronic obstructive pulmonary disease (COPD). METHODS: Muscarinic cholinergic receptors have been identified and characterized by radioligand binding assay in the lung tissue specimens of patients with COPD. Competitive binding experiments with pirenzepine and methoctramine were used to characterize muscarinic subtypes. RESULTS: The contents of M-receptor were (64 +/- 10), (42 +/- 18) fmol/mg. protein in normal group and COPD patients respectively. No significant difference was observed in antagonist affinity (K(D)) among normal group and COPD patients. The ratio of subtype M(1) was higher in COPD patients (67.2 +/- 2.7)% than in normal group (74.2 +/- 4.8)%, M(2) was lower [(29.3 +/- 1.7)% vs (16.8 +/- 4.4)%] and M(3) was higher [(3.6 +/- 2.9) % vs (9.3 +/- 4.1)%] respectively. CONCLUSION: The number of muscarinic cholinergic receptors is decreased in COPD patients, but the ratios of subtype M(1) and M(3) are increased and the subtype M(2) is decreased. The changes of the distribution of the subtypes of M-receptors is an important pathophysiologic change of COPD.

Female↗
PubMed2002

Modulation of bladder alpha1-adrenergic receptor subtype expression by bladder outlet obstruction.

PURPOSE: alpha1-Adrenergic receptor (alpha1AR) antagonists are effective for relieving obstructive and irritative symptoms in patients with bladder outlet obstruction. While the alpha1aAR is responsible for prostate smooth muscle relaxation and outlet obstruction relief, to our knowledge the mechanisms underlying the relief of irritative symptoms remain to be determined. Therefore, we investigated mechanisms by which bladder alpha1AR subtypes may be involved in this process. MATERIALS AND METHODS: We studied 42 rats, including 6 unoperated controls, 17 sham operated controls and 19 obstructed animals. Animals were characterized for baseline voiding pattern, followed by surgical intervention or sham surgery to establish obstruction (1.09 mm. restricted opening). After 6 weeks to enable the development of detrusor hypertrophy, voiding behavior was reexamined, the animals were sacrificed and bladder tissue was immediately placed in liquid nitrogen. alpha1AR subtype messenger (m)RNA was quantitated using quantitative competitive reverse transcriptase-polymerase chain reaction and protein expression was determined using radioligand binding with the alpha1AR antagonist [125iodine]2-(-[4-hydroxyphenyl]-ethyl-aminomethyl)tetralone (saturation analysis for total alpha1AR density and competition analysis with BMY7378 and 5-methylurapidel to determine alpha1AR subtypes). RESULTS: In this model 6-week surgical obstruction produced a 6.3-fold increase in bladder weight versus sham operation (p <0.001), concurrent with increased voiding frequency versus before obstruction (p <0.004). Although bladder alpha1AR density did not increase overall with obstruction, striking changes in alpha1AR subtype expression occurred. In control animals 70% of alpha1AR mRNA was the alpha1a subtype, 5% were alpha1b and 25% were alpha1d, whereas in obstructed animals bladder alpha1AR expression changed to 23% alpha1a, 2% alpha1b and 75% alpha1d. Changes in alpha1AR mRNA expression were of similar magnitude throughout the bladder dome, mid body and base. Parallel changes were also evident at the protein level with 100% alpha1aAR expression in control animals changing to new onset alpha1dAR expression (mean plus or minus standard error of mean 36% +/- 7%) in animals with a 5-fold or greater increase in bladder weight. CONCLUSIONS: Our findings indicate a remarkable increase in bladder alpha1dAR mRNA and protein expression after 6 weeks of obstruction and resultant detrusor hypertrophy. This finding is potentially important since alpha1dARs have 10 to 100-fold higher affinity for the endogenous neurotransmitter norepinephrine than the alpha1a or alpha1bAR subtypes. These findings imply that targeting alpha1d may provide a new therapeutic approach for controlling bladder irritative symptoms and possibly detrusor overactivity associated with bladder outlet obstruction.

Animals↗
PubMed2001

[Genetic subtyping of HIV-1 in Liaoning province of China].

OBJECTIVE: To study the prevalence of HIV-1 in Liaoning province of China. METHODS: Nuclear acids were extracted from blood samples of 16 HIV-1 infected individuals collected locally in Liaoning province of China from Jun. 1997 to Dec. 2000. The 0.7 kb or 1.2 kb segments of HIV-1 env gene were amplified using nested-PCR and the HIV-1 genetic subtypes were then assayed by heteroduplex mobility assay. RESULTS: Fifteen of 16 samples were positive by PCR amplification of HIV-1 env region and samples were found to be genetic subtype A,B',C,E. The proportion due to sexual transmission in all HIV infection was 31.25% (5/15), among which subtype B' (3/5) was the majority. A man who returned from Africa together with his spouse both had type A (2/5) infection. Intravenous drug users (IDUs) took up 31.25% (5/15) of all the HIV infections. Subtype C (2/4) and E were predominant among intravenous drug users. However, there was one IDU with subtype B or E. Nearly all blood recipients and blood donors were B' (4/5) except one with C. CONCLUSION: There have been several subtypes of HIV-1 existed in Liaoning province, demonstrating the complexity of HIV epidemology in Liaoning province and the difficulty conducting prevention and treatment.

Acquired Immunodeficiency Syndrome↗
PubMedDate not supplied

Diversity of HIV-1 subtype E in semen and cervicovaginal secretion.

OBJECTIVES: To characterize human immunodeficiency virus type 1 (HIV-1) subtype E variants in blood and genital fluid of infected Thai couples. STUDY DESIGN/METHODS: Blood and genital fluid were collected from 30 asymptomatic healthy HIV-1 subtype E infected couples from Bangkok, Thailand from 1995 to 1998. RESULTS: All 60 viruses in blood samples were identified as subtype E by heteroduplex mobility assay. The biotype of viruses founded in blood was syncytium-inducing (SI), whereas M-tropic and non-syncytium-inducing (NSI) isolates were predominantly detected in genital fluid. HIV-1 proviral DNA was detected in 43.33% and 56.67%, and viral RNA was detected in 93.33% and 56.67%, of semen (n = 30) and cervicovaginal secretion (n = 30) samples tested, respectively. A higher intersample genetic distance and more positive charge of the V3 loop were found in blood strains composed of genital fluid strains (22.30 +/- 5.92% and 17.96 +/- 6.3%), which was statistically significant (P = 0.003). The env V1-V4 intraperson variation of the HIV-1 subtype E in the blood and genital fluid of each individual was in the range 3.0%-5.7%. We also determined the intrasample variation of HIV-1 from blood and genital fluid by heteroduplex mobility assay. The mean heteroduplex mobility of the HIV-1, V1-V4 region of env gene, in blood (n = 8) and genital fluid (n = 8) was 0.59 +/- 0.06 and 0.74 +/- 0.11 (t test, p = 0.001), respectively. CONCLUSIONS: There was genetic and phenotypic compartmentalization of HIV-1 subtype E in blood and genital fluid with the presence of SI and NSI phenotypic variants as a common property of subtype E isolates from blood and genital fluid, respectively.

Cervix Uteri↗
PubMed2002

Bombesin receptor subtypes in human cancers: detection with the universal radioligand (125)I-[D-TYR(6), beta-ALA(11), PHE(13), NLE(14)] bombesin(6-14).

PURPOSE: Bombesin and bombesin receptors have been shown to play a role in cancer. Whereas the gastrin-releasing peptide (GRP) receptor is a bombesin receptor subtype frequently expressed by tumors, the other three subtypes, the neuromedin B (NMB), BB3, and BB4 receptors, have been poorly investigated in human tissues. EXPERIMENTAL DESIGN: We investigated 161 human tumors for their bombesin receptor subtype expression using in vitro receptor autoradiography with the universal bombesin radioligand (125)I-[D-Tyr(6), beta-Ala(11), Phe(13), Nle(14)]bombesin(6-14) in displacement experiments with unlabeled GRP, bombesin, NMB, and [D-Tyr(6), beta-Ala(11), Phe(13), Nle(14)]bombesin(6-14). The distinct rank order of potencies of these analogues for each receptor subtype allows us to identify the predominant subtype expressed by each tumor. RESULTS: Twelve of 12 prostate cancers, 41 of 57 breast cancers, and 5 of 5 gastrinomas expressed predominantly GRP receptors; 11 of 24 intestinal, 1 of 26 bronchial, and 1 of 1 thymic carcinoids had preferentially NMB receptors; 9 of 26 bronchial carcinoids, 1 large cell neuroendocrine lung carcinoma, and 4 of 9 small cell lung carcinomas had preferentially BB3 receptors, whereas 3 of 9 small cell lung carcinomas had GRP receptors. Renal cell carcinomas had GRP receptors in 6 of 16 cases and BB3 receptors in 4 of 16 cases. Finally, 2 of 10 Ewing sarcomas had BB3 receptors. In situ hybridization detected BB3 receptor mRNA in neuroendocrine tumors expressing the BB3 protein. CONCLUSIONS: This is the first study detecting the proteins of BB3, NMB, and GRP receptors in a group of human tumors using differential binding techniques. Particularly relevant is the BB3 expression in lung carcinoids and other neuroendocrine lung tumors, whereas gastrointestinal carcinoids preferably express NMB receptors. These tumors may be targets for diagnostic and radiotherapeutic applications of subtype-selective bombesin analogues.

Autoradiography↗
PubMed2002

[Application of heteroduplex mobility assay in genetic subtyping on human immunodeficiency virus type 1].

OBJECTIVE: Using heteroduplex mobility assay (HMA) to subtype human immunodeficiency virus type 1 (HIV-1) for the purpose of understanding HIV-1 subtype epidemic in Fujian province. METHODS: DNA fragments of HIV-1 env gene were amplified from peripheral blood mononuclear cell (PBMC) cocultures of HIV-1 infected individuals by nested polymerase chain reaction (PCR). Heteroduplexs were formed through hybridizing PCR products from the samples and reference plasmid. According to the mobility of heteroduplexs in polyacrylamide gel electrophoresis, HIV-1 subtype from that sample was characterized and further confirmed by nucleotide sequencing analysis. RESULTS: Thirteen of 15 (86.67%) samples were successfully subtyped by HMA, except 2 failures. Subtype E and B took up 80% (12/15) and 6.67% (1/15) respectively. Results indicated a high concordance between HMA and nucleotide sequencing analysis and concordance rate was 86.67% (13/15). CONCLUSIONS: Subtype E appeared to be the major epidemic strain of HIV-1 in Fujian. HMA showed the characteristics of fastness, easiness, economic and with high specificity, and can be used in the surviellance for the epidemic strain of HIV-1.

Genotype↗
PubMed2001

Muscarinic receptor subtypes in the heart--how many and why?

Muscarinic receptors are coupled to G proteins and to date, five subtypes have been characterized. These subtypes differ in their effects on second messenger production. Odd-numbered subtypes activate phospholipase C beta, and then they increase the production of inositoltrisphosphate and diacylglycerol. Even-numbered subtypes inhibit adenylylcyclase. The expression of individual subtypes is quite tissue specific. The heart tissue is realized as M2 predominant organ (in mammals; the muscarinic population in birds consist of M2 and M4 receptors). This article focuses on the possibility of existence of further muscarinic receptor subtypes in avian and mammalian heart in consequences with activation of phosphoinositid metabolism in the heart.

Animals↗
PubMed2002

[Clinical impact of gamma-glutamyl transpeptidase messenger RNA subtypes on early diagnosis of hepatocellular carcinoma].

BACKGROUND & OBJECTIVE: It has been reported that hepatocellular carcinoma (HCC) expresses gamma-glutamyl transpeptidase (GGT) with unique carbohydrate moieties compared with normal liver GGT enzymes, this unique GGT was used as a marker for the diagnosis of HCC. However, the genomic changes in GGT relating to the development of HCC are not known. This study was designed to explore the relationship between alteration in GGTmRNA subtypes and the development of HCC, and to seek a new method for early diagnosis of HCC. METHODS: Three GGTmRNA subtypes (F, H, P) were determined bu using RT-PCR in normal liver tissues, diseased liver tissues without HCC, cancerous and noncancerous tissues from the livers with HCC, noncancerous tissues from secondary carcinoma of liver and peripheral blood of all cases. RESULTS: The main subtype of GGTmRNA was type F in normal liver tissues, liver tissues from noncancerous liver diseases and paracancerous tissues from secondary carcinoma of liver. The prevalence of subtype H was significantly higher in cancerous tissues, adjacent paracancerous and distal cancerous tissues from the livers with HCC than that in tissues from normal livers and noncancerous liver diseases (P < 0.05). The prevalence of subtype F in cancerous tissues was significantly lower than that in tissues from normal livers and noncancerous liver diseases (P < 0.05). Among 26 patients with HCC, GGTmRNA-H in peripheral blood was found in 12 cases. In 10 HCC patients with negative AFP, GGTmRNA-H in peripheral blood was found in 5 cases. CONCLUSIONS: The changes of GGTmRNA subtypes are closely related to the development of HCC, and the analysis of GGT genes might be a sensitive assay to monitor the hepatic cell canceration.

Carcinoma, Hepatocellular↗
PubMed2003

Characterization of cAMP accumulation mediated by three alpha1-adrenoceptor subtypes in HEK293 cells.

AIM: To investigate the characterization of cAMP response mediated by alpha1-adrenoceptor (alpha1-AR) subtypes in HEK293 cells. METHODS: (1) Full-length cDNA encoding three alpha1-AR subtypes were transfected into HEK293 cells by the calcium phosphate precipitation method, respectively. (2) The densities of alpha1-AR subtypes expressed in HEK293 cells were measured by radioligand binding assay. (3) cAMP accumulation was measured by [3H]adenine prelabeling method. RESULTS: (1) Activation of each of three subtypes resulted in an increase of cAMP accumulation in HEK293 cells in a dose-dependent manner, which was inhibited by selective alpha1-AR antagonist prazosin. (2) Comparing the pharmacological property, the maximal responses of alpha1A-AR to agonists were the most potent, while the sensitivity of alpha1-AR subtypes to norepinephrine (NE) was the highest. CONCLUSION: Each of three alpha1-AR subtypes can mediate cAMP accumulation in HEK293 cell line, and there are differences in pharmacological property.

Cell Line↗
PubMed1992

Amino terminus of the interleukin-8 receptor is a major determinant of receptor subtype specificity.

Interleukin-8 (IL-8) is a key mediator in the migration of neutrophils from the circulation to the site of inflammation in the tissue. IL-8 is secreted by many cell types in response to proinflammatory stimuli such as interleukin 1, tumor necrosis factor, and lipopolysaccharide and is a potent chemoattractant and activator of neutrophils. Neutrophil activating peptide-2 (NAP-2) and melanoma growth-stimulatory activity (MGSA/GRO) are structurally and functionally related to IL-8 and, like IL-8, bind to specific G protein-coupled receptors on neutrophils. In the present study two closely related cloned IL-8 receptor subtypes are characterized by expression of the cDNA clones in monkey kidney cells (COS-7) or chinese hamster ovary cells and analysis of their ligand binding profiles. Both receptor subtypes bind 125I-labeled IL-8 with similar high affinity, however, the F3R receptor binds IL-8 exclusively, while the 4Ab receptor binds both IL-8 and MGSA/GRO with high affinity and NAP-2 with lesser affinity. Furthermore, we demonstrate with the use of intersubtype chimeric receptors that the specificity of ligand binding to both IL-8 receptor subtypes is dictated by the heterogeneous NH2-terminal domain. The F3R receptor is representative of a restricted IL-8 receptor subtype, and 4Ab represents a nonrestricted receptor subtype. It is proposed that these subtypes be named IL-8 receptors alpha and beta, respectively.

Amino Acid Sequence↗
PubMedDate not supplied

Role of the host microenvironment on the expression of VEGF-subtypes in squamous cell carcinoma.

The phenotypic characteristics and function of microvascular endothelium differs from tissue to tissue because of the organ specific microenvironment. Even the neovasculature in tumors differs depending upon tumor location. These findings indicate that local regulatory pathways modulate endothelial-cell growth and -function in a tissue specific manner. This might be mediated by novel tissue-specific regulators or the tissue specific regulation of known proteins. One of the major proangiogenic factors is VEGF. Its importance for tumor vascularisation and growth has been shown in several studies. VEGF is expressed in several subtypes and its impact on initial tumor growth and tumor progression has been discussed. Many of these results have been obtained by xenotransplantation studies in mice. The influence of the mouse microenvironment on the VEGF-subtype expression has not been previously analyzed. In the present study we analyzed the impact of the nude mouse microenvironment on the expression of the VEGF-subtypes after subcutaneous xenotransplantation. Our study was performed on seven squamous cell carcinoma (SCC) cell lines. We analyzed by quantitative PCR the mRNA-expression levels and the proportion of the subtypes -121, -165, -189, and of VEGF-total of established xenotransplanted tumors and compared them to the cell lines prior to transplantation. We found high VEGF-165 fractions in the cell lines leading to fast growing, large tumors. The proportion of the VEGF-isoforms remaining in the cell lines and xenotransplanted tumors were generally unchanged, but an overall decrease of VEGF by about 50% was observed. We conclude that the VEGF-subtypes expressed by the transplanted tumors are not differentially regulated by the nude mouse subcutaneous microenvironment and that the tumor growth characteristics are not dependent on VEGF-subtype regulation of the host.

Animals↗
PubMed1992

Cloning of two mouse genes encoding alpha 2-adrenergic receptor subtypes and identification of a single amino acid in the mouse alpha 2-C10 homolog responsible for an interspecies variation in antagonist binding.

Molecular cloning and ligand binding studies have shown the alpha 2 class of adrenergic receptor (alpha 2-AR) to be a family of at least three related subtypes in humans. These studies have not, however, identified distinct subtype-specific functions for these receptors in vivo. It should be possible to extend the analysis of alpha 2-AR subtype function to the animal level through the use of experimental mammalian embryology in mice. To begin this process, we have isolated two mouse genomic clones encoding alpha 2-AR subtypes and expressed these genes in COS-7 cells for binding studies. Sequence homology and ligand binding data allow the assignment of one clone (M alpha 2-4H) as the mouse homolog of the human alpha 2-C4 subtype. The other clone (M alpha 2-10H) closely resembles the human alpha 2-C10 subtype in sequence but binds with significantly lower affinity to yohimbine and rauwolscine, members of a distinct class of bulky alpha 2-selective antagonists commonly used to evaluate alpha 2-AR function in vivo. To define the domain(s) responsible for this unusual binding property, we constructed a series of M alpha 2-10H/human alpha 2-C10 chimeric receptors. Analysis of these receptors identified a conservative Cys201 to Ser201 change in the fifth transmembrane domain of M alpha 2-10H as being responsible for the low affinity of the mouse receptor for yohimbine.

Adrenergic alpha-Antagonists↗
PubMed1992

Electrophysiological analyses of serotonergic actions on neurons in hypothalamic ventromedial nucleus in vitro: receptor subtypes involved and implications for regulation of feeding and lordosis behaviors.

Previously, we have shown that serotonin (5-HT) can inhibit, excite, or biphasically inhibit and excite individual neurons of the ventromedial nucleus (VMN) in hypothalamic slices from female rats. In the present study, similar in vitro methods were used to further characterize VMN neurons responsive to 5-HT, and to identify the receptor subtypes involved in mediating these 5-HT actions. Results from a dose-response experiment indicate that increasing the dose of 5-HT can transform an inhibitory response into a biphasic or even an excitatory response. This indicates that modulation of 5-HT release in the VMN could alter the net response of the VMN to this transmitter. By comparing the actions of 5-HT with the effects of selective agonists and antagonists, the inhibitory action was found to be mediated predominantly, if not exclusively, by 5-HT1A receptors, while the excitatory action was mediated predominantly or exclusively through 5-HT2 receptors. There appear to be few, if any, 5-HT3 receptors in the VMN, and their functions are unclear. The inhibitory and the excitatory phases of the biphasic responses were not mediated together by a single receptor subtype but were mediated separately by 5-HT1A and 5-HT2 receptors, respectively. The presence of the biphasic response in a large proportion of neurons, therefore, indicates the coexistence of different subtypes of 5-HT receptors in many individual VMN neurons. The use of selective agonists and antagonists further indicates that the coexistence also occurs in neurons showing monophasic responses, and that the opposite actions mediated by the coexisting receptor subtypes can interact with each other. Therefore, changing the ratio of coexisting receptor subtypes could modify the net output of the VMN response to 5-HT. Together with behavioral studies by others, it emerges from our findings that the inhibitory action of 5-HT on VMN neurons is associated with, and may be responsible for, the stimulation of feeding and inhibition of lordosis, while the excitatory action is related and may lead to the opposite behavioral effects. Finally, with the coexistence in VMN neurons of two receptor subtypes that can mediate 5-HT effects on both feeding and lordosis, the VMN can serve as a substrate for 5-HT to coordinate these two behaviors.

8-Hydroxy-2-(di-n-propylamino)tetralin↗
PubMed2003

Expression of MMP-2 and -9 in short-term cultures of meningioma: influence of histological subtype.

Matrix metalloproteinases (MMPs) belong to a super family of endopeptidases which have been implicated as crucial mediators of angiogenesis and tumour invasion in brain tumours. This study was undertaken in an attempt to establish the relationship between 2 specific MMPs and the main classical subtypes of meningioma. We examined the expression of MMP-2 and -9 (gelatinase-A and -B respectively), by gelatin zymography, in a series of 18 cell cultures derived from human meningiomas of a range of histological subtypes and grades of malignancy, including 7 meningothelial, 6 transitional, 2 fibroblastic and 3 atypical meningiomas. Our findings indicate that generally, the meningothelial subtype, had the weakest expression, the transitional subtype had an intermediate expression whereas the fibroblastic subtype had the strongest expression of both MMP-2 and -9. There was no correlation between other clinicopathological features (age, sex, site of tumour) and the level of MMP-2 and -9 expression. Although, the number of samples in this study is limited, these findings suggest that there may be a trend for association between the expression of these 2 MMPs and the main classical histological subtypes of meningioma.

Adult↗
PubMed2004

Comparison of the pharmacological properties of rat Na(V)1.8 with rat Na(V)1.2a and human Na(V)1.5 voltage-gated sodium channel subtypes using a membrane potential sensitive dye and FLIPR.

A novel, membrane potential sensitive dye and a fluorescence imaging plate reader (FLIPR) have been used to characterize the pharmacological properties of rat Na(v)1.8 voltage-gated sodium channels (VGSC) in parallel with rat Na(v)1.2a and human Na(v)1.5 VGSC subtypes, respectively. The sensitivity of recombinant Na(v)1.2a-CHO, Na(v)1.5-293-EBNA, and Na(v)1.8-F-11 cells to VGSC activators was subtype dependent. Veratridine evoked depolarization of Na(v)1.2a-CHO and Na(v)1.5-293-EBNA cells with pEC(50) values of 4.78 +/- 0.13 and 4.84 +/- 0.12, respectively (n = 3), but had negligible effect on Na(v)1.8-F-11 cells (pEC(50) < 4.5). Type I pyrethroids were without significant effect at all subtypes. In contrast, the type II pyrethroids deltamethrin and fenvalerate evoked direct depolarization of Na(v)1.8-F-11 and Na(v)1.5-293-EBNA cells. Deltamethrin potentiated the veratridine-evoked response in Na(v)1.8-F-11 cells by > or =20-fold, in contrast to a <or =3-fold potentiation of the response in Na(v)1.2a, and Na(v)1.5 cells. Tetrodotoxin (TTX) inhibited VGSC activator-evoked depolarization of Na(v)1.8-F-11 cells with a biphasic concentration-response curve. The calculated pIC(50) values were 8.05 +/- 0.25 (n = 4) and 4.32 +/- 0.21 (n = 4), corresponding to TTX inhibition of endogenous TTX-sensitive (TTX-S), and recombinant Na(v)1.8 TTX-resistant (TTX-R) VGSCs, respectively. With the exception of TTX, the potencies of a number of ion channel blockers for the Na(v)1.8, Na(v)1.2a, and Na(v)1.5 VGSC subtypes were similar. In summary, these high-throughput FLIPR assays represent a valuable tool for the determination of the relative potencies of compounds at different VGSC subtypes and may prove useful for the identification of novel subtype-selective inhibitors.

Animals↗
PubMedDate not supplied

Prevalence of HLA-B27 and subtypes of HLA-B27 associated with ankylosing spondylitis in Galicia, Spain.

OBJECTIVE: To assess the prevalence of HLA-B27 and its subtypes in both the normal population and in patients with Ankylosing Spondylitis (AS) in Galicia, Northwest Spain. METHODS: The prevalence of HLA-B27 in the normal population was determined by checking the number of HLA-B27 positive samples in 308 subjects from different areas of Galicia who had donated organs over a period of 4 years. A total of 106 patients with the diagnosis of AS, according to the modified New York clinical criteria for definitive ankylosing spondylitis, were collected from three very representative areas of Galicia. HLA-B27 was determined by PCR using the primers E91s and E136as, while 11 subtypes of HLA-B27 were analyzed using a commercial kit. RESULTS: The prevalence of HLA-B27 in organ donors was 9.34%. HLA-B27 was present in 94.3% of patients with AS. Subtypes B*2701, B*2709 and B*2710 were not found. The subtypes found in the normal population were; B*2705 (79.5%), B*2702 (18%) and B*2708 (2.5%). The subtypes associated with AS were B*2705 (88%) and B*2702 (12%). CONCLUSION: The prevalence of HLA-B27 in Galicia was 9.34%, which is higher than previously published in Spain. The frequency of the subtypes associated with AS was similar to that reported for other Spanish regions.

DNA↗
PubMed1992

Characterization of renal angiotensin II receptors using subtype selective antagonists.

Two angiotensin II (AII) receptor subtypes, AT1 and AT2, have recently been identified based on their relative affinities for selective peptide and nonpeptide antagonists. In the present study we used various AII peptide analogs, the AT1 subtype selective antagonists, DuP 753 and SK&F 108566, and the AT2 subtype selective antagonists, WL-19 and CGP 42112A, to determine whether AII receptor subtypes exist in the kidney. In agreement with previous studies, octapeptide (Sar1,Ile8-AII) and heptapeptide (AIII and Ile8-AIII) AII analogs displaced [125I]AII bound to rat glomerular membranes with similar affinities. However, in membranes derived from cortical tubules and the outer medulla, the heptapeptide analogs were 20-fold less potent in competing with [125I]AII binding than octapeptide analogs. The AT1 subtype selective nonpeptide AII antagonists, DuP 753 and SK&F 108566, totally displaced [125I]AII binding from all three membrane preparations in a monophasic manner with IC50 values in the 5 to 30 nM range. The AT2 selective peptide antagonist, CGP 42112A, had a low affinity in AII three membranes (IC50 = 450-1050 nM), whereas the nonpeptide AT2 selective antagonist, WL-19, had no activity at concentrations up to 10 microM. Dithiothreitol and the nonhydrolyzable GTP analog, 5'-guanylyl-imidodiphosphate, inhibited AII binding to all three membrane preparations. Based on these results, we conclude that the AII receptors located on glomeruli, tubules and in the outer medulla belong to the AT1 subtype, and that the physiologically important renal actions of AII are mediated through activation of AT1 receptors.

Acrylates↗
PubMed2003

[Common carotid artery intima-media thickness, carotid atherosclerosis and subtypes of ischemic cerebral disease].

INTRODUCTION: Common carotid artery intima-media thickness (CCA-IMT) measurements are widely used to study atherosclerosis. CCA-IMT is a useful outcome measure in clinical studies and intervention trials because it reflects early stages of atherosclerosis and cardiovascular risk. The present study examined the relationship between common carotid artery intima-media thickness and ischemic brain infarction. MATERIAL AND METHODS: The present study examined the association between CCA-IMT and incidence of ischemic stroke and its subtypes in 75 cases and 21 controls. Cases with internal borderzone infarction (IBI) were consecutively recruited and classified into subtypes using CT and Bamford's classification. It classifies cerebral infarctions regarding vascular territory using clinical features to determine the size and site of infarction. These subtypes included: total anterior circulation infarctions (TACIs), partial anterior circulation infarctions (PACIs), posterior circulation infarctions (POCIs), and lacunar infarctions (LACIs). Controls were recruited among individuals hospitalized at the same institution and matched for age and sex. Patients and control subjects underwent B-mode ultrasonographic measurements of IMT of the far wall of both common carotid arteries. RESULTS: Of 75 patients with acute ischemic stroke, 10 (14%) were classified as TACIs, 34 (45%) had PACIs, 12 (16%) had POCIs and 19 (25%) had LACIs. Mean CCA-IMT was higher in investigation group (1.03+/-0.18 mm) than in controls (0.85+/-0.18 mm; p<0.0001). The difference in CCA-IMT between investigation group and controls was significant and the relation between CCA-IMT and IBI remained unchanged after adjustments of main cardiovascular risk factors. Regarding the subtypes of IBI, IMT values were significantly higher in patients with TACIs and PACIs versus those with LACIs and POCIs. CONCLUSIONS: An increased CCA-IMT was established in all subtypes of IBI and was significantly higher in those with anterior circulation infarctions versus posterior circulation and lacunar infarctions. This study points to importance of noninvasive measurement of CCA-IMT with ultrasonographic techniques as a diagnostic tool for selecting patients at high risk for IBI and identifying different subtypes of ischemic stroke.

Arteriosclerosis↗