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971.
Maria Luisa Brandi Luigi Gennari Marco Matucci Cerinic Lucia Becherini Alberto Falchetti Laura Masi Carlo Gennari Jean-Yves Reginster 《Arthritis research & therapy》2001,3(5):270-11
Osteoarthritis and osteoporosis are the two most common age-related chronic disorders of articular joints and skeleton, representing
a major public health problem in most developed countries. Apart from being influenced by environmental factors, both disorders
have a strong genetic component, and there is now considerable evidence from large population studies that these two disorders
are inversely related. Thus, an accurate analysis of the genetic component of one of these two multifactorial diseases may
provide data of interest for the other. However, the existence of confounding factors must always be borne in mind in interpreting
the genetic analysis. In addition, each patient must be given an accurate clinical evaluation, including family history, history
of drug treatments, lifestyle, and environment, in order to reduce the background bias. Here, we review the impact of recent
work in molecular genetics suggesting that powerful molecular biology techniques will soon make possible both a rapid accumulation
of data on the genetics of both disorders and the development of novel diagnostic, prognostic, and therapeutic approaches. 相似文献
972.
Giuseppe M. Campo Salvatore Campo Alida M. Ferlazzo Rosalia Vinci Alberto Calatroni 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》2001,765(2):151-160
An improved isocratic high-performance liquid chromatography (HPLC) method for the analysis of
-(−)-fucose,
-(+)-galactosamine,
-(+)-glucosamine,
-(+)-galactose, obtained by hydrolysis of glycosaminoglycans (GAGs) and
-(+)-glucose and
-(+)-mannose is described. The presence in circulation of GAGs, acid polysaccharide sequences of alternate monosaccharide units, aminosugar and uronic acid (galactose in keratan sulfate), has been measured in terms of their sugar components. To evaluate concentration of these circulating sugars we considered blood samples obtained from healthy humans. Plasma or serum was filtered through weak anion-exchange Ecteola-cellulose either untreated or after mild alkaline treatment. GAGs adhering to resin were recovered by salt elution, and desalted on Bio-Gel P-2 resin. GAG fractionation by charge was carried out on a strong anion exchanger. GAG composition was evaluated in terms of galactose and aminosugars, measured in HPLC by the proposed procedure using anion-exchange resin and pulsed amperometric detection. The mobile phase consisted of 0.02 M NaOH and elution was carried out at flow-rate of 1.0 ml/min. The amperometric detector was set as follows: t1 (0.5 s), E1 (+0.1 V); t2 (0.09 s), E2 (+0.6 V); t3 (0.05 s), E3 (−0.6 V). The analysis required 14 min. Calibration standard curves for the six analytes were linear from 0.25 to 40 μM. RSD values for intra- and inter-day variabilities were ≤5.3% at concentrations between 0.25 and 40 μM. Accuracy, expressed as percentage error, ranged from −16 to 14%. The method was specific and sensitive with quantitation limits of 1 pmol for
-(−)-fucose,
-galactosamine and
-glucosamine, 3 pmol for
-(+)-galactose and
-(+)-glucose and 5 pmol for
-(+)-mannose. The results of the assay showed higher GAG concentrations in serum than in plasma. 相似文献
973.
Molecular mechanisms underlying SHP-1 gene expression. 总被引:2,自引:0,他引:2
974.
Alberto Luis Cione 《Geobios》2002,35(3):367
The first record of the knifejaw family Oplegnathidae in the Atlantic Ocean and in South America is reported. It comes from the lowermost beds of the Early Miocene Gaiman Formation at the lower Río Chubut valley, central-eastern Patagonia. The family Oplegnathidae does not occur in the Atlantic today, but it was widespread in comparison to other knifejaw fishes, such as scarids and odacids. Several aquatic vertebrates were extirpated from the southern Atlantic Ocean in the Late Neogene. This record establishes a minimal age (Early Miocene) for the extirpation of the family Oplegnathidae in the Atlantic Ocean. 相似文献
975.
Inhibition of human MDA-MB-231 breast cancer cell invasion by matrix metalloproteinase 3 involves degradation of plasminogen. 总被引:7,自引:0,他引:7
Antonietta R Farina Antonella Tacconelli Lucia Cappabianca Alberto Gulino Andrew R Mackay 《European journal of biochemistry》2002,269(18):4476-4483
Matrix metalloproteinase (MMP)-3 inhibited human MDA-MB-231 breast cancer cell invasion through reconstituted basement membrane in vitro. Inhibition of invasion was dependent upon plasminogen and MMP-3 activation, was impaired by the peptide MMP-3 inhibitor Ac-Arg-Cys-Gly-Val-Pro-Asp-NH2 and was associated with: rapid MMP-3-mediated plasminogen degradation to microplasminogen and angiostatin-like fragments; the removal of single-chain urokinase plasminogen activator from MDA-MB-231 cell membranes; impaired membrane plasminogen association; reduced rate of tissue plasminogen activator (t-PA) and membrane-mediated plasminogen activation; and reduced laminin-degrading capacity. Purified human plasminogen lysine binding site-1 (kringles 1-3) exhibited a similar capacity to inhibit MDA-MB-231 invasion, impair t-PA and cell membrane-mediated plasminogen activation and impair laminin degradation by plasmin. Our data provide evidence that MMP-3 can inhibit breast tumour cell invasion in vitro by a mechanism involving plasminogen degradation to fragments that limit plasminogen activation and the degradation of laminin. This supports the hypothesis that MMP-3, under certain conditions, may protect against tumour invasion, which would help to explain why MMP-3 expression, associated with benign and early stage breast tumours, is frequently lost in advanced stage, aggressive, breast disease. 相似文献
976.
Maren Pink Pierre Sutra Vincenzo BalzaniMargherita Venturi Sebastiano CampagnaScolastica Serroni Alberto Juris 《Inorganica chimica acta》2002,333(1):25-31
The structure and reactivity of the complex [Ru(2,3-Medpp)2Cl2](PF6)2 (2,3-Medpp+=2-[2-(1-methylpyridiniumyl)]-3-(2-pyridyl)pyrazine) was investigated by X-ray diffraction (XRD), 1H NMR, redox, and UV-Vis absorption measurements. X-ray analysis shows that crystals obtained from an acetonitrile-toluene solution contain the trans-Cl2, trans-pyrazine isomeric form, while 1H NMR and redox measurements on the main product of the synthetic workup indicate the presence of the trans-Cl2, cis-pyrazine isomer. In the dark at 70 °C, the complex [Ru(2,3-Medpp)2Cl2]2+ reacts slowly in acetonitrile isomerizing to the cis-[Ru(2,3-Medpp)2(CH3CN)Cl]3+ species. Under ambient light in the presence of excess AgNO3 the cis-[Ru(2,3-Medpp)2(CH3CN)2]4+ species is obtained. 相似文献
977.
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