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1.
BMC Genet ; 18(1): 4, 2017 01 19.
Artigo em Inglês | MEDLINE | ID: mdl-28103813

RESUMO

BACKGROUND: FTO gene variants have been associated with obesity phenotypes in sedentary and obese populations, but rarely with skeletal muscle and elite athlete phenotypes. METHODS: In 1089 participants, comprising 530 elite rugby athletes and 559 non-athletes, DNA was collected and genotyped for the FTO rs9939609 variant using real-time PCR. In a subgroup of non-resistance trained individuals (NT; n = 120), we also assessed structural and functional skeletal muscle phenotypes using dual energy x-ray absorptiometry, ultrasound and isokinetic dynamometry. In a subgroup of rugby athletes (n = 77), we assessed muscle power during a countermovement jump. RESULTS: In NT, TT genotype and T allele carriers had greater total body (4.8% and 4.1%) and total appendicular lean mass (LM; 3.0% and 2.1%) compared to AA genotype, with greater arm LM (0.8%) in T allele carriers and leg LM (2.1%) for TT, compared to AA genotype. Furthermore, the T allele was more common (94%) in selected elite rugby union athletes (back three and centre players) who are most reliant on LM rather than total body mass for success, compared to other rugby athletes (82%; P = 0.01, OR = 3.34) and controls (84%; P = 0.03, OR = 2.88). Accordingly, these athletes had greater peak power relative to body mass than other rugby athletes (14%; P = 2 x 10-6). CONCLUSION: Collectively, these results suggest that the T allele is associated with increased LM and elite athletic success. This has implications for athletic populations, as well as conditions characterised by low LM such as sarcopenia and cachexia.


Assuntos
Dioxigenase FTO Dependente de alfa-Cetoglutarato/genética , Músculo Esquelético/metabolismo , Polimorfismo de Nucleotídeo Único , Treinamento Resistido , Adolescente , Adulto , Atletas , Futebol Americano , Predisposição Genética para Doença , Genótipo , Humanos , Masculino , Fenótipo , Adulto Jovem
2.
Physiol Genomics ; 48(3): 196-201, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26757799

RESUMO

We aimed to quantify the ACE I/D and ACTN3 R577X (rs1815739) genetic variants in elite rugby athletes (rugby union and league) and compare genotype frequencies to controls and between playing positions. The rugby athlete cohort consisted of 507 Caucasian men, including 431 rugby union athletes that for some analyses were divided into backs and forwards and into specific positional groups: front five, back row, half backs, centers, and back three. Controls were 710 Caucasian men and women. Real-time PCR of genomic DNA was used to determine genotypes using TaqMan probes and groups were compared using χ(2) and odds ratio (OR) statistics. Correction of P values for multiple comparisons was according to Benjamini-Hochberg. There was no difference in ACE I/D genotype between groups. ACTN3 XX genotype tended to be underrepresented in rugby union backs (15.7%) compared with forwards (24.8%, P = 0.06). Interestingly, the 69 back three players (wings and full backs) in rugby union included only six XX genotype individuals (8.7%), with the R allele more common in the back three (68.8%) than controls (58.0%; χ(2) = 6.672, P = 0.04; OR = 1.60) and forwards (47.5%; χ(2) = 11.768, P = 0.01; OR = 2.00). Association of ACTN3 R577X with playing position in elite rugby union athletes suggests inherited fatigue resistance is more prevalent in forwards, while inherited sprint ability is more prevalent in backs, especially wings and full backs. These results also demonstrate the advantage of focusing genetic studies on a large cohort within a single sport, especially when intrasport positional differences exist, instead of combining several sports with varied demands and athlete characteristics.


Assuntos
Actinina/genética , Atletas , Futebol Americano , Estudos de Associação Genética , Mutação INDEL/genética , Peptidil Dipeptidase A/genética , Polimorfismo de Nucleotídeo Único/genética , Adulto , Alelos , Frequência do Gene/genética , Humanos , Masculino
3.
J Pept Res ; 65(3): 322-32, 2005 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-15787962

RESUMO

We previously reported that the novel dynorphin A (Dyn A, Tyr-Gly-Gly-Phe-Leu-Arg-Arg-Ile-Arg-Pro-Lys-Leu-Lys-Trp-Asp-Asn-Gln) analog arodyn (Ac[Phe(1,2,3),Arg(4),d-Ala(8)]Dyn A-(1-11)NH(2), Bennett, M.A., Murray, T.F. & Aldrich, J.V. (2002) J. Med. Chem. vol. 45, pp. 5617-5619) is a kappa opioid receptor-selective peptide [K(i)(kappa) = 10 nm, K(i) ratio (kappa/mu/delta) = 1/174/583] which exhibits antagonist activity at kappa opioid receptors. In this study, a series of arodyn analogs was prepared and evaluated to explore the structure-activity relationships (SAR) of this peptide; this included an alanine scan of the entire arodyn sequence, sequential isomeric d-amino acid substitution in the N-terminal 'message' sequence, NMePhe substitution individually in positions 1-3, and modifications in position 1. The results for the Ala-substituted derivatives indicated that Arg(6) and Arg(7) are the most important residues for arodyn's nanomolar binding affinity for kappa opioid receptors. Ala substitution of the other basic residues (Arg(4), Arg(9) and Lys(11)) resulted in lower decreases in affinity for kappa opioid receptors (three- to fivefold compared with arodyn). Of particular interest, while [Ala(10)]arodyn exhibits similar kappa opioid receptor binding as arodyn, it displays higher kappa vs. mu opioid receptor selectivity [K(i) ratio (kappa/mu) = 1/350] than arodyn because of a twofold loss in affinity at mu opioid receptors. Surprisingly, the Tyr(1) analog exhibits a sevenfold decrease in kappa opioid receptor affinity, indicating that arodyn displays significantly different SAR than Dyn A; [Tyr(1)]arodyn also unexpectedly exhibits inverse agonist activity in the adenylyl cyclase assay using Chinese hamster ovary cells stably expressing kappa opioid receptors. Substitution of NMePhe in position 1 gave [NMePhe(1)]arodyn which exhibits high affinity [K(i)(kappa) = 4.56 nm] and exceptional selectivity for kappa opioid receptors [K(i) ratio (kappa/mu/delta) = 1/1100/>2170]. This peptide exhibits antagonistic activity in the adenylyl cyclase assay, reversing the agonism of 10 nm Dyn A-(1-13)NH(2). Thus [NMePhe(1)]arodyn is a highly kappa opioid receptor-selective antagonist that could be a useful pharmacological tool to study kappa opioid receptor-mediated activities.


Assuntos
Dinorfinas/química , Dinorfinas/farmacologia , Receptores Opioides kappa/antagonistas & inibidores , Alanina/química , Substituição de Aminoácidos , Animais , Células CHO , Cricetinae , Cricetulus , Peptídeos/síntese química , Ensaio Radioligante , Relação Estrutura-Atividade
4.
Inorg Chem ; 40(17): 4271-5, 2001 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-11487332

RESUMO

The binuclear cycloaurated compounds [Au(2)(mu-C(6)H(3)-2-PPh(2)-n-Me)(2)] (n = 5, 1a; n = 6, 1b) react with the digold(I) complexes [Au(2)(mu-S(2)CN(n)()Bu(2))(2)] and [Au(2)(mu-dppm)(2)](PF(6))(2) to give heterobridged dinuclear complexes [Au(2)(mu-C(6)H(3)-2-PPh(2)-n-Me)(mu-S(2)CN(n)Bu(2))] (n = 5, 5a; n = 6, 5b) and [Au(2)(mu-C(6)H(3)-2-PPh(2)-n-Me)(mu-dppm)]PF(6), (n = 5, 9a; n = 6, 9b), respectively. Complex 5a exists in the solid state as an infinite zigzag chain of dimeric units with intramolecular Au-Au separations of 2.8331(3) and 2.8243(3) A for independent molecules and intermolecular Au-Au separations of 3.0653(3) and 3.1304(3) A. Both 5a and 5b undergo oxidative addition with halogens to give the heterovalent, gold(I)-gold(III) compounds [XAu(I)(mu-2-Ph(2)PC(6)H(3)-n-Me)Au(III)X(eta(2)-S(2)CN(n)Bu(2))] [n = 5, X = Cl (6a), I (8a); n = 6, X = Cl (6b), Br (7b), I (8b)]. Compound 8a has been shown by X-ray crystallography to contain a gold(III) atom coordinated in a planar array by bidentate, chelating di-n-butyldithiocarbamate, iodide, and the sigma-aryl carbon atom, together with a gold(I) atom that is linearly coordinated by the phosphorus atom of the arylphosphine and by iodide. The intramolecular gold-gold distance of 3.2201(3) A indicates little or no interaction between the metal atoms. In contrast to the behavior of the homobridged complexes 1a and 1b, the heterobridged dithiocarbamate complexes 5a and 5b give structurally similar products on reaction with halogens, irrespective of the position of the ring methyl substituent. Crystal data for [Au(2)(mu-C(6)H(3)-2-PPh(2)-5-Me)(mu-S(2)CN(n)Bu(2))] (5a): triclinic, space group P1 (No. 2), with a = 11.3398(1), b = 15.9750(2), c = 16.4400(3) A, alpha = 91.0735(9), beta = 109.3130(7), gamma = 90.7666(8) degrees, V = 2809.47(6) A(3), and Z = 4. Crystal data for [IAu(I)(mu-2-Ph(2)PC(6)H(3)-5-Me)Au(III)I(eta(2)- S(2)CN(n)Bu(2))] (8a): triclinic, space group P1 (No. 2), with a = 8.6136(2), b = 9.3273, c = 21.1518(4) A, alpha = 84.008(1), beta = 84.945(1), gamma = 75.181(1) degrees, V = 1630.54(6) A(3), and Z = 2.

5.
EMBO J ; 19(13): 3204-14, 2000 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-10880434

RESUMO

The avrPphF gene was cloned from Pseudomonas syringae pathovar phaseolicola (PPH:) races 5 and 7, based on its ability to confer avirulence towards bean cultivars carrying the R1 gene for halo-blight resistance, such as Red Mexican. avrPphF comprised two open reading frames, which were both required for function, and was located on a 154 kb plasmid (pAV511) in PPH: Strain RW60 of PPH:, lacking pAV511, displayed a loss in virulence to a range of previously susceptible cultivars such as Tendergreen and Canadian Wonder. In Tendergreen virulence was restored to RW60 by avrPphF alone, whereas subcloned avrPphF in the absence of pAV511 greatly accelerated the hypersensitive resistance reaction caused by RW60 in Canadian Wonder. A second gene from pAV511, avrPphC, which controls avirulence to soybean, was found to block the activity of avrPphF in Canadian Wonder, but not in Red Mexican. avrPphF also conferred virulence in soybean. The multiple functions of avrPphF illustrate how effector proteins from plant pathogens have evolved to be recognized by R gene products and, therefore, be classified as encoded by avirulence genes.


Assuntos
Genes Bacterianos , Glycine max/microbiologia , Pseudomonas/patogenicidade , Sequência de Bases , Clonagem Molecular , DNA Bacteriano/genética , Fenótipo , Plasmídeos , Pseudomonas/genética , Análise de Sequência de DNA , Virulência/genética
6.
Gut ; 46(2): 200-4, 2000 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-10644313

RESUMO

AIMS: To examine the relation between the replication error (RER) phenotype and other genetic events, clinical features, and long term survival in patients with Dukes' B stage II (T3,N0,M0) colorectal cancer. METHODS: RER phenotype was investigated in 159 patients by PCR amplification of microsatellite marker loci on chromosomes 5q, 17p, 17q, and 18q from tumour DNA extracted from archival tissue. Data on activating c-Ki-ras mutations were available from a previous study. Immunohistochemical detection of p53 and c-erbB-2 expression was performed on paraffin wax embedded tissue. RESULTS: Of 159 colorectal cancers studied, 22 (14%) were RER+ while 137 (86%) were RER- for two or more loci. RER+ tumours were more commonly located in the right colon, tended to be larger than RER- tumours, and were more often poorly differentiated than RER- cancers. No significant associations were seen between RER status and the presence of a mutant c-Ki-ras gene, or between RER status and p53, c-erbB-2, or c-myc gene expression. Univariate survival analysis showed that outcome was similar in RER+ and RER- cases. Multivariate survival analysis showed that the relative risk of death for patients with RER+ cancers was 0.95 that of patients with RER- cancers. CONCLUSIONS: The results suggest that, while the RER phenotype may be associated with some differences in tumour pathology (site, size, differentiation), it is not associated with the genetic alterations studied or with significant differences in long term survival.


Assuntos
Neoplasias Colorretais/genética , Neoplasias Colorretais/patologia , Replicação do DNA/genética , Idoso , Feminino , Genes ras , Marcadores Genéticos , Humanos , Masculino , Repetições de Microssatélites/genética , Pessoa de Meia-Idade , Mutação , Estadiamento de Neoplasias , Proteínas Proto-Oncogênicas c-myc/análise , Receptor ErbB-2/análise , Estatísticas não Paramétricas , Análise de Sobrevida , Proteína Supressora de Tumor p53/análise
7.
Mol Microbiol ; 29(1): 165-77, 1998 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-9701811

RESUMO

The bean halo blight pathogen, Pseudomonas syringae pv. phaseolicola (Psph), is differentiated into nine races based on the presence or absence of five avirulence (avr) genes in the bacterium, which interact with corresponding resistance genes. R1-R5, in Phaseolus vulgaris. The resistance gene R2 is matched by avrPphE, which is located adjacent to the cluster of hrp genes that are required for pathogenicity of Psph. Although only races 2, 4, 5 and 7 are avirulent on cultivars with R2 (inducing the hypersensitive response; HR), homologues of avrPphE are present in all races of Psph. DNA sequencing of avrPphE alleles from races of Psph has demonstrated two routes to virulence: via single basepair changes conferring amino acid substitutions in races 1, 3, 6 and 9 and an insertion of 104bp in the allele in race 8. We have demonstrated that these base changes are responsible for the difference between virulence and avirulence by generating transconjugants of a virulent race harbouring plasmids expressing the various alleles of avrPphE. Agrobacterium tumefaciens-directed expression of avrPphE from race 4 in bean leaves induced the HR in a resistance gene-specific manner, suggesting that the AvrPphE protein is alone required for HR induction and is recognized within the plant cell. The allele from race 6, which is inactive if expressed in Psph, elicited a weak HR if expressed in planta, whereas the allele from race 1 did not. Our results suggest that the affinity of interaction between AvrPphE homologues and an unknown plant receptor mediates the severity of the plant's response. Mutation of avrPphE alleles did not affect the ability to colonize bean from a low level of inoculum. The avirulence gene avrPphB, which matches the R3 resistance gene, also caused a gene-specific HR following expression in the plant after delivery by A. tumefaciens.


Assuntos
Alelos , Fabaceae/microbiologia , Genes Bacterianos , Variação Genética , Plantas Medicinais , Pseudomonas/genética , Pseudomonas/patogenicidade , Sequência de Aminoácidos , Sequência de Bases , DNA Bacteriano , Dados de Sequência Molecular , Mutagênese Insercional , Virulência
8.
Hum Pathol ; 29(6): 559-64, 1998 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-9635674

RESUMO

The distribution of p21WAf1/CiP1, MDM2, and Bax/Bcl-2 proteins in ultraviolet (UV)-irradiated and nonirradiated human skin was examined immunohistochemically and compared with p53 protein levels. Sun-protected buttock skin from three volunteers was exposed to solar simulated irradiation, and biopsies were performed 0.5, 1, 2, 4, and 24 hours after irradiation as well as control unirradiated skin from the opposite buttock. A similar staining pattern was observed in each of the three volunteers. P53 protein was detectable in all skin samples examined. P21Waf1/CiP1 protein was visible in the nuclei of cells at 4 hours, and staining intensity increased at 24 hours. MDM2 protein expression was noted in isolated nuclei in the epidermis at 24 hours. Bax cytoplasmic staining was evident in the basal layer of the epidermis of all samples, and this staining appeared to increase in intensity in the 4- and 24-hour specimens. There was no Bcl-2 immunohistochemical staining in any sample. These results suggest that p53 and genes/proteins under the control of p53 are altered/ activated in normal human skin in response to UV exposure.


Assuntos
Ciclinas/metabolismo , Proteínas Nucleares , Proteínas Proto-Oncogênicas/metabolismo , Lesões Experimentais por Radiação/metabolismo , Pele/efeitos da radiação , Proteína Supressora de Tumor p53/metabolismo , Idoso , Animais , Inibidor de Quinase Dependente de Ciclina p21 , Inibidores Enzimáticos/metabolismo , Feminino , Humanos , Imuno-Histoquímica , Masculino , Pessoa de Meia-Idade , Proteínas de Neoplasias/metabolismo , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Proteínas Proto-Oncogênicas c-mdm2 , Lesões Experimentais por Radiação/etiologia , Lesões Experimentais por Radiação/patologia , Pele/metabolismo , Pele/patologia , Raios Ultravioleta/efeitos adversos , Proteína X Associada a bcl-2
9.
Adv Wound Care ; 10(5): 16-9, 1997 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-9362572

RESUMO

The National Pressure Ulcer Advisory Panel appointed a task force to review the definition of Stage I pressure ulcers, specifically to assess its adequacy in people with darkly pigmented skin. The process used by the task force to draft a new definition is described in this preliminary report of their work. The proposed definition and initial critique of it are given.


Assuntos
Guias de Prática Clínica como Assunto , Úlcera por Pressão/classificação , Úlcera por Pressão/diagnóstico , Pigmentação da Pele , Humanos
12.
Diabet Med ; 14(1): 82-5, 1997 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-9017359

RESUMO

Sudden death at night is known to occur in young patients with insulin-dependent (Type 1) diabetes mellitus (IDDM) but the aetiology is uncertain. A cardiac arrhythmia has been postulated, but there has been little evidence to support this. We present the case of a 31-year-old man with IDDM of 17 years duration, who died suddenly while asleep. Over preceding months, he had had strict glycaemic control (HbA1 8.9%), normal 24 h blood pressure (mean 131 +/- 2.1/76 +/- 2.2 mmHg), no evidence of microangiopathy or endothelial dysfunction and normal standard clinical tests of autonomic function. An electrocardiogram was similarly unremarkable, with a QTc interval of 0.414 s, and an echocardiogram had demonstrated normal left ventricular mass index (96.4 g m-2). However, there was no nocturnal dip in heart rate (daytime 74 +/- 2.7, and nocturnal 68 +/- 1.6 beats min-1), and he had grossly impaired baroreflex sensitivity during Phase 4 of the valsalva manoeuvre (0.5 ms mmHg-1), with power spectral analysis studies suggesting an abnormality of parasympathetic function. The coroner's autopsy demonstrated no structural abnormalities. We hypothesize that abnormal baroreflex sensitivity could either predict a risk of or account for some of the unexplained deaths in IDDM, in that relative overactivity of the sympathetic nervous system could cause ventricular arrhythmias.


Assuntos
Barorreflexo/fisiologia , Morte Súbita/etiologia , Diabetes Mellitus Tipo 1/mortalidade , Adulto , Diabetes Mellitus Tipo 1/fisiopatologia , Frequência Cardíaca/fisiologia , Humanos , Masculino
13.
J Hypertens ; 14(3): 389-97, 1996 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-8723994

RESUMO

OBJECTIVE: To examine the effects of different types of antihypertensive treatment on endothelium-dependent relaxation in resistance arteries from spontaneously hypertensive rats (SHRs). DESIGN AND METHODS: Three-week-old SHRs were treated with the angiotensin converting enzyme (ACE) inhibitor perindopril (1 mg/kg/day) or quinapril (3 mg/kg/day) or the vasodilator hydralazine (50 mg/kg/day) or the calcium antagonist amlodipine (10 mg/kg/day). Control SHRs and Wistar-Kyoto (WKY) rats were treated with water. After 21 weeks rats were culled and mesenteric resistance arteries were mounted in a myograph. Relaxation responses to the endothelium-dependent vasodilators acetylcholine (ACh) and bradykinin were recorded before and after incubation with the nitric oxide synthase inhibitor NG-nitro-L-arginine (L-NOARG), as was the relaxation response to the nitric oxide donor sodium nitroprusside (SNP). RESULTS: All drugs prevented the rise in blood pressure found in the untreated SHRs. ACh-induced relaxation was significantly impaired in the untreated SHRs compared with the WKY rats. Treatment with either ACE inhibitor prevented the development of this impaired response. ACE inhibitor treatment significantly increased the relaxation response to bradykinin. Despite lowering blood pressure, hydralazine or amlodipine had no effect on ACh- or bradykinin-induced relaxation. Responses to SNP were not different between untreated SHRs and WKY rats and were not affected by drug treatment. CONCLUSION: Specific properties of certain antihypertensive drugs may play an important role in restoring endothelium-dependent relaxation in the small arteries that regulate peripheral resistance in the SHR.


Assuntos
Anlodipino/farmacologia , Anti-Hipertensivos/farmacologia , Endotélio Vascular/fisiologia , Hidralazina/farmacologia , Hipertensão/tratamento farmacológico , Indóis/farmacologia , Isoquinolinas/farmacologia , Tetra-Hidroisoquinolinas , Vasodilatação/efeitos dos fármacos , Acetilcolina/farmacologia , Animais , Arginina/análogos & derivados , Arginina/farmacologia , Bradicinina/farmacologia , Relação Dose-Resposta a Droga , Hipertensão/fisiopatologia , Artérias Mesentéricas/efeitos dos fármacos , Artérias Mesentéricas/fisiologia , Nitroarginina , Perindopril , Quinapril , Ratos , Ratos Endogâmicos SHR , Ratos Endogâmicos WKY
14.
Clin Sci (Lond) ; 90(1): 21-9, 1996 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-8697701

RESUMO

1. This study was designed to examine the effect of angiotensin-converting enzyme inhibitors on resistance artery structure and endothelium-dependent relaxation in Goldblatt two-kidney, one-clip hypertensive rats. Four weeks after clipping, hypertensive and sham rats were treated with either perindopril (1 mg day-1 kg-1) or quinapril (3 or 30 mg day-1 kg-1). After 6 weeks mesenteric resistance arteries were mounted in a myograph for measurements of vascular structure. The endothelium-dependent relaxation response to acetylcholine and bradykinin and the response to the nitric oxide donor sodium nitroprusside were recorded. 2. All treatment regimes lowered the blood pressure and reversed both cardiac and resistance artery hypertrophy. Two-kidney, one-clip rats treated with quinapril showed a dose-dependent reduction in media cross-sectional area and media to lumen ratio. 3. Hypertension of 10 weeks' duration was associated with an impaired endothelium-dependent relaxation response to acetylcholine and bradykinin. Treatment with perindopril and either dose of quinapril prevented the development of impaired endothelium-dependent relaxation but had no effect on the response to sodium nitroprusside. Treatment had no effect on endothelium-dependent relaxation in sham rats. 4. Angiotensin-converting enzyme inhibitor treatment is effective in normalizing blood pressure and cardiovascular structural changes. Angiotensin-converting enzyme inhibitor treatment prevented the development of impaired endothelium-dependent relaxation to both acetylcholine and bradykinin. The ability of angiotensin-converting enzyme inhibitors to reverse cardiovascular structural changes and prevent the development of abnormal endothelium-dependent relaxation may contribute to the overall effect of this type of antihypertensive drug.


Assuntos
Inibidores da Enzima Conversora de Angiotensina/farmacologia , Anti-Hipertensivos/farmacologia , Hipertensão Renovascular/tratamento farmacológico , Tetra-Hidroisoquinolinas , Resistência Vascular/efeitos dos fármacos , Acetilcolina/farmacologia , Animais , Pressão Sanguínea/efeitos dos fármacos , Bradicinina/farmacologia , Constrição , Endotélio Vascular/efeitos dos fármacos , Endotélio Vascular/fisiopatologia , Hipertensão Renovascular/patologia , Hipertensão Renovascular/fisiopatologia , Indóis/farmacologia , Isoquinolinas/farmacologia , Masculino , Relaxamento Muscular/efeitos dos fármacos , Músculo Liso Vascular/efeitos dos fármacos , Perindopril , Quinapril , Ratos , Ratos Wistar
15.
Clin Mol Pathol ; 48(6): M310-5, 1995 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-16696029

RESUMO

Aims-To determine possible associations between p53 allelic deletion, c-Ki-ras mutational activation, immunohistochemical detection of p53 and ras proteins, various clinicopathological variables, and patient outcome in 168 Dukes' stage B colorectal carcinomas.Methods-Allelic deletion at the p53 tumour suppressor gene locus was detected using polymerase chain reaction (PCR) based loss of heterozygosity (LOH) assays. Overexpressed proteins were detected using the CM1 polyclonal antibody. A PCR based assay was used to detect the presence of activating mutations at codon 12 of c-Ki-ras. Immunostaining was carried out using a monoclonal antibody to p21(ras).Results-p53 LOH, CM1 immunostaining, c-Ki-ras mutational activation, and p21(ras) immunostaining were not predictive of survival by logrank analysis. Multivariate analysis using Cox regression did not predict survival in this group of tumours.Conclusions-Aberrations in ras and p53 are unlikely to play an important role in the subdivision of patients with Dukes' stage B colorectal carcinoma into more accurate prognostic strata. It is possible that later genetic events are more important in conferring a specific phenotype on the resultant Dukes' stage B tumour.

16.
Br J Pharmacol ; 116(8): 3251-9, 1995 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-8719804

RESUMO

1. Previous studies have shown that endothelium-dependent relaxation in the aorta of spontaneously diabetic bio bred rats (BB) is impaired. 2. We have investigated noradrenaline (NA) contractility, endothelium-dependent acetylcholine (ACh) and bradykinin (BK) relaxation, and endothelium-independent sodium nitroprusside (SNP) relaxation in mesenteric resistance arteries of recent onset BB rats and established insulin treated BB rats, compared to their age-matched non diabetic controls. 3. There was no significant difference in the maximum contractile response or sensitivity to noradrenaline in either of the diabetic groups compared to their age-matched controls. 4. Incubation with the nitric oxide synthetase inhibitor NG-nitro-L-arginine (L-NOARG) resulted in a significant increase in maximum contractile response to noradrenaline in the recent onset age-matched control group (P < 0.05). Analysis of the whole dose-response curve (using ANOVA for repeated measures with paired t test) showed a significant left-ward shift following the addition of L-NOARG (P < 0.001). A similar but less marked shift (P < 0.01) was evident in vessels from recent onset diabetics. An overall shift in both sensitivity and maximum response was also evident in the age-matched non diabetic controls of the insulin-treated group (P < 0.05). However, by contrast, there was no significant change in sensitivity in the insulin-treated diabetic rats. 5. ACh-induced endothelium-dependent relaxation was significantly impaired in the recent onset diabetic rats compared to their age-matched controls (47 +/- 11% versus 92 +/- 2%, P < 0.05, n = 6), and in the insulin treated diabetic rats (34 +/- 5% versus 75 +/- 6%, P < 0.05, n = 6). The relaxation responses to BK also were significantly impaired in the diabetic rats compared to their age-matched controls (recent onset: 20 +/- 3% versus 72 +/- 7%, P < 0.05, n = 6; insulin treated: 12 +/- 9% versus 68 +/- 7%, P < 0.05, n = 7). 6. Incubation with either the nitric oxide synthetase substrate, U-arginine, or the free radical scavenging enzyme superoxide dismutase (150 mu ml-1) failed to improve the attenuated response of acetylcholine-induced relaxation in the diabetic vessels. 7. Endothelium-dependent relaxation mediated by ACh and BK was significantly attenuated in both the diabetic and control vessels after incubation with L-NOARG. 8. Pretreatment with a cyclo-oxygenase inhibitor, indomethacin, significantly enhanced the relaxation to ACh in both the recent onset and insulin treated diabetic rats (42 +/- 10%, n = 7 versus 64 +/- 7%, n = 7, P < 0.05, and 40 +/- 5%, n = 7 versus 65 +/- 9%, n = 6, P < 0.05). 9. Following endothelium removal, there was a marked impairment in endothelium-dependent relaxation responses to ACh and BK in both the diabetic and control vessels. 10. Incubation with the thromboxane A2 receptor antagonist SQ29548, did not significantly improve the ACh endothelium-dependent relaxation response in the diabetic vessels. 11. Endothelium-independent relaxation to sodium nitroprusside was significantly impaired in the first group of diabetic vessels studied; however, subsequent studies showed no impairment of the sodium nitroprusside response in the diabetic vessels. 12. In conclusion, the ability of the endothelium to regulate vascular contractility is reduced in recent onset diabetic vessels, and significantly impaired in established insulin treated diabetics. Relaxation to the endothelium-dependent vasodilators ACh and BK was impaired in both the recent onset and the established insulin treated diabetics, and the ACh response was significantly improved following pretreatment with indomethacin, suggesting a role for a cyclo-oxygenase-derived vasoconstrictor. Preliminary studies with a thromboxane A2, receptor antagonist, SQ29548 did not significantly improve the impaired relaxation to ACh, indicating that the vasoconstrictor prostanoid is not thromboxane A2.


Assuntos
Acetilcolina/farmacologia , Agonistas alfa-Adrenérgicos/farmacologia , Diabetes Mellitus Tipo 1/fisiopatologia , Endotélio Vascular/efeitos dos fármacos , Nitroprussiato/farmacologia , Norepinefrina/farmacologia , Circulação Esplâncnica/efeitos dos fármacos , Vasodilatadores/farmacologia , Animais , Arginina/análogos & derivados , Arginina/farmacologia , Bradicinina/farmacologia , Diabetes Mellitus Tipo 1/tratamento farmacológico , Endotélio Vascular/fisiopatologia , Técnicas In Vitro , Insulina/administração & dosagem , Microcirculação/efeitos dos fármacos , Óxido Nítrico Sintase/antagonistas & inibidores , Nitroarginina , Ratos , Ratos Endogâmicos BB
18.
Mol Plant Microbe Interact ; 7(6): 726-39, 1994.
Artigo em Inglês | MEDLINE | ID: mdl-7873779

RESUMO

The avirulence gene matching the R2 gene for resistance to halo-blight disease in Phaseolus was cloned and sequenced from race 4 strain 1302A of Pseudomonas syringae pv. phaseolicola. The predicted 41-kDa AvrPphE protein is hydrophilic, has no features that indicate function, and no similarity to other protein sequences. The promoter region of avrPphE contains a "harp box" motif. The gene was expressed more strongly in minimal than in nutrient-rich media. Lower concentrations of the phytoalexin phaseollin accumulated in tissue undergoing the hypersensitive reaction (HR) determined by avrPphE than by avrPphB. Homologs of avrPphE were detected in strains representing eight races of P. s. pv. phaseolicola including those virulent on cultivars with the R2 resistance gene, and in P. s. pv. tabaci but not in P. cichorii or P. s. pvs. coronafaciens, glycinea, maculicola, pisi, or syringae. Disruption of avrPphE prevented induction of the HR but did not appear to affect basic pathogenicity. Transposon mutagenesis and DNA sequencing showed that avrPphE was linked to hrpY a hrp locus identified at the left end of the hrp gene cluster. Sequence analysis showed that the region linked to avrPphE was very similar to DNA containing hrp genes from P. s. pv. syringae including hrpJ, hrpL, and hrpK.


Assuntos
Genes Bacterianos , Pseudomonas/genética , Sequência de Aminoácidos , Sequência de Bases , Clonagem Molecular , DNA Bacteriano , Fabaceae/microbiologia , Ligação Genética , Dados de Sequência Molecular , Doenças das Plantas/microbiologia , Plantas Medicinais , Pseudomonas/patogenicidade , Homologia de Sequência de Aminoácidos , Virulência/genética
19.
Leuk Lymphoma ; 14 Suppl 1: 33-9, 1994.
Artigo em Inglês | MEDLINE | ID: mdl-7820051

RESUMO

Hairy cell leukemia (HCL) is a chronic lymphoproliferative disorder of the B cell lineage. In the search for specific markers with prognostic significance we evaluated the clinical value of IL-1 beta and sIL-2R levels in HCL patients. HCL patients (25) were classified according to their clinical status as "active", "non active" disease or partial or complete remission and response treatment. We found a good correlation between IL-1 beta or IL-2R levels and disease activity: improved clinical status or response to different therapies were associated with decreasing IL-1 beta or sIL-2R levels. In contrast, lack of response to therapy or disease progression was reflected in increases in both IL-1 beta and sIL-2R levels. In some patients increases of both cytokines preceded clinical symptoms. In conclusion our results show that IL-1 beta and s-IL-2R levels may be used as reliable markers for monitoring HCL activity, assessing response to treatment and predicting early progression of disease.


Assuntos
Biomarcadores Tumorais/sangue , Interleucina-1/sangue , Leucemia de Células Pilosas/sangue , Leucemia de Células Pilosas/patologia , Receptores de Interleucina-2/metabolismo , Progressão da Doença , Humanos , Solubilidade
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