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51.
T. Angelone E. Filice A. M. Quintieri S. Imbrogno A. Recchia E. Pulerà C. Mannarino D. Pellegrino M. C. Cerra 《Acta physiologica (Oxford, England)》2008,193(3):229-239
Aims: Using a model of isolated and Langendorff‐perfused rat heart we analysed whether activation of β3‐adrenergic receptors (β3‐ARs) influences ventricular lusitropic performance. We also focused on the NOS/NO/cGMP/PKG cascade as the signal transduction mechanism. Methods: Hearts were treated with increasing concentrations (from 10?12 to 10?6 m ) of BRL37344, a selective β3‐AR agonist, and cardiac performance was evaluated by analysing both lusitropic parameters and coronary motility. Cardiac preparations were also perfused with BRL37344 in the presence of either isoproterenol (ISO) or nadolol, or pertussis toxin (PTx), or selective inhibitors of the NOS/NO/cGMP/PKG pathway. Results: BRL37344 caused a significant concentration‐dependent reduction in (LVdP/dt)min, a decrease in half time relaxation significant starting from 10?12 m , and an increase in (LVdP/dt)max/(LVdP/dt)min ratio (T/?t). BRL37344 abolished the ISO‐mediated positive lusitropism. β3‐AR‐dependent effects on relaxation were insensitive to β1/β2‐AR inhibition by nadolol (100 nm ), and were abolished by Gi/o protein inhibition by PTx (0.01 nm ). NO scavenging by haemoglobin (10 μm ), and nitric oxide synthase (NOS) inhibition by NG‐monomethyl‐l ‐arginine (10 μm ) revealed the involvement of NO signalling in BRL37344 response. Pre‐treatment with inhibitors of either soluble guanylate cyclase (ODQ; 10 μm ) or PKG (KT5823; 100 nm ) abolished β3‐AR‐dependent negative lusitropism. In contrast, anantin (10 nm ), an inhibitor of particulate guanylate cyclase, did not modify the effect of BRL37344 on relaxation. Conclusion: Taken together, our findings provide functional evidence for β3‐AR modulation of ventricular relaxation in the rat heart which involves PTx‐sensitive inhibitory Gi protein and occurs via an NO‐cGMP‐PKG cascade. Whether the effects of β3‐AR stimulation on lusitropism are beneficial or detrimental remains to be established. 相似文献
52.
Amills M Sulas C Sànchez A Bertoni G Zanoni R Obexer-Ruff G 《Molecular immunology》2005,42(3):375-379
The major histocompatibility class II DQ molecules are dimeric glycoproteins involved in antigen presentation to CD4(+) T cells. In the current work, we have performed the molecular analysis of the goat Cahi-DQA1 gene. Sequencing of the Cahi-DQA1 cDNA revealed a single 768bp open reading frame. The alignment of this sequence with its bovine and ovine DQA1 counterparts revealed a remarkable degree of nucleotide identity (92-93% for the most similar bovine and ovine sequences). Moreover, we amplified a region including the 3'-end of intron 1, exon 2 and the 5'-end of intron 2. We identified seven Cahi-DQA1 alleles that likely correspond to four different allelic lineages. The alignment of these seven Cahi-DQA1 alleles revealed the existence of 23 amino acid polymorphic sites, seven of which (alpha(10), alpha(55), alpha(56), alpha(68), alpha(69), alpha(71) and alpha(76)) are highly polymorphic with at least three amino acid substitutions. Ten of the 23 polymorphic amino acid sites were included in the peptide binding region and consequently they might play a crucial role in immunological processes modulating disease pathogenesis. 相似文献
53.
Establishment of the paternal methylation imprint of the human H19 and MEST/PEG1 genes during spermatogenesis 总被引:9,自引:0,他引:9
Kerjean A Dupont JM Vasseur C Le Tessier D Cuisset L Pàldi A Jouannet P Jeanpierre M 《Human molecular genetics》2000,9(14):2183-2187
Parental-specific epigenetic modifications are imprinted on a subset of genes in the mammalian genome during germ cell maturation. However, the precise timing of their establishment remains to be determined. Methylation of CpG dinucleotides has been shown to be a part of the parental imprint. We have examined how the methylation pattern characteristic of the paternal allele in germ cells are established during human spermatogenesis. Two representative imprinted genes, H19 and MEST/PEG1, were studied. The experiments were performed using the bisulphite sequencing method on microdissected individual cells at different stages of male germ cell differentiation. We show that both genes are unmethylated in fetal spermatogonia, suggesting that all pre-existing methylation imprints are already erased by this stage. The MEST/PEG1 gene remains unmethylated at all subsequent post-pubertal stages of spermatogenesis, including mature spermatozoa. The methylation of H19 typical of the paternal allele first appears in a subset of adult spermatogonia and then is maintained in spermatocytes, spermatids and mature spermatozoa. Our results suggest that the methylation imprint inherited from the parents is first erased in the male germ line at an early fetal stage. The paternal-specific imprint is re-established only later, during spermatogonial differentiation in the adult testis. 相似文献
54.
E. Zanette L. Bozzao C. Buttinelli A. Mariottini S. Pappatà G. L. Lenzi 《Acta neurochirurgica》1987,89(1-2):43-47
Summary Tumour growth essentially requires fibrin formation and fibrinopeptide A (FPA) is liberated into the circulation on fibrin formation. In the present study, a possible elevation of serum FPA level was examined in patients with metastatic brain tumour. A significant elevation of serum FPA level was shown in all 6 patients with metastatic brain tumour, when blood was drawn from the internal jugular vein. It was extremely high in 2 patients with rapidly growing tumour. However, such a significant elevation was not shown in 3 cancer patients without brain metastasis or in 1 patient with a huge meningioma. This suggests the possibility that the presence of metastatic brain tumour could be detected by measuring FPA in blood drawn form the internal jugular vein. This also suggests the tendency that elevation of serum FPA is higher in patients with more rapidly growing tumour.Infusion of urokinase into the internal carotid artery resulted in an elevation of serum fibrinopeptide B (1)15–42 (FPB) in 5 patients with metastatic brain tumour, when blood was drawn from the internal jugular vein. This suggests that urokinase could induce fibrinolysis in the tumour tissue, though this remains in conclusive because of the lack of complete controls. 相似文献
55.
56.
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58.
Lorente Nicolas Sherriff Nigel Panochenko Oksana Marcus Ulrich Dutarte Maria Kuske Matthias Aussó Susanna Huber Jörg Krone Michael Schink Susanne Barbara Cawley Caoimhe Casabona Jordi Folch Cinta 《Journal of community health》2021,46(3):545-556
Journal of Community Health - Little is known about Community Health Workers (CHWs) who work in non-clinical settings to provide sexual health support around HIV, viral hepatitis, and other... 相似文献
59.
M. Divizia C. Gnesivo R. Amore Bonapasta G. Morace G. Pisani A. Panà 《European journal of epidemiology》1993,9(2):203-208
From April 28th to May 22nd, 1987, the Medical Authority identified 13 cases (6 symptomatic cases) of hepatitis A (HA) in a school and in a college of Rome.The principal risk factor was determined to be full-time presence at the State school and boarders at the college. The distribution of HA cases suggested a person to person contact; antihepatitis A virus IgM were identified in 12 out of 13 cases with high levels of transaminases.During the disease epidemic, water samples were taken from the well of the college for bacteriological and virological analyses. The water was classified as undrinkable due to the presence of 16 total coliforms/100 ml and 35 total bacteria count at 36° C.Fecal coliforms, fecal streptococci and sulfite reducing clostridia were absent. Two water samples of 100 liters were collected and concentrated by adsorption-elution method on electropositive membranes or by ultrafiltration using a Millipore apparatus.Infectious Hepatitis A virus was only isolated from samples concentrated by adsorption-elution method on electropositive membranes using tissue culture methods and subsequently HA virus was identified by other traditional methods (Elisa and immunofluorescence). In contrast, PCR test performed on the concentrated samples, was positive only for the ultraconcentrated sample. The positivity of the PCR test confirmed the presence of the Hepatitis A virus in the well water. 相似文献
60.
Dominici Carlo Nicotra Maria Rita Alemaà Stefano Bosman Cesare Castello Manuel A. Donfrancesco Alberto Gallo Pietro Natali Pier Giorgio 《Journal of neuro-oncology》1997,31(1-2):57-64
In neuroblastoma, high levels of mRNA for p14h
trkA
and p75
LNGFR
neurotrophin receptors are predictive of favorable outcome. Their evaluation by Northern blot, however, requires substantial amounts of tissue and this prevents their routine evaluation as well as the possibility for multicenter studies to be easily carried out. In an attempt to overcome these limitations, the feasibility and reliability of determining both neurotrophin receptors on cryostat sections by immunohistochemistry were assessed, and these findings were compared to those obtained from Northern blot analysis. Primary tumor samples from 28 untreated patients at all stages were evaluated by using H10 anti-p140
trkA
and ME20.4 anti-p75
LNGFR
mAbs. Although weak, positiveimmunostaining was found in 9 of 28 tumors for p140
trkA
and in 5 of 28 tumors for p75
LNGFR
. As compared to Northern blot, the concordance rate was 79% (22 of 28 cases) for p140
trkA
(p < 0.05) and 71% (20 of 28 cases) for p75
LNGFR
(p < 0.05). No case negative for Northern blot was found to be positive with immunohistochemistry. Since only high mRNA levels for both receptors have been shown to be clinically relevant, their immunohistochemical detection, although less sensitive than Northern blot, can be just as sufficient and reliable as a prognostic tool, and possibly with a better cost-benefit ratio. 相似文献