Search results for "Hydroxyproline"

Inhibition of prolyl hydroxylation and procollagen processing in chick-embryo calvaria by a derivative of pyridine-2,4-dicarboxylate. Characterizatio…

1991

The biochemical and morphological consequences of procollagen prolyl 4-hydroxylase inhibition by pyridine-2,4-dicarboxylic acid (2,4-PDCA) and its diethyl ester (diethyl-2,4-PDC) were studied in chick-embryo calvaria, which predominantly synthesize type I collagen. Half-maximal inhibition of tissue hydroxyproline formation required 650 microM-2,4-PDCA, whereas the Ki with respect to chicken prolyl 4-hydroxylase in vitro was 2 microM. In contrast, half-maximal inhibition was caused by 10 microM-diethyl-2,4-PDC in the intact calvaria, although chicken prolyl 4-hydroxylase in vitro was not inhibited even at 1 mM. The collagenous material produced in the presence of diethyl-2,4-PDC showed an al…

Determination of Pyrrole Derivatives and Hydroxyproline with 4-(Dimethylamino)benzaldehyde in a Micellar Medium

1994

Abstract The spectrophotometric determination of pyrrole derivatives and hydroxyproline with 4-(dimethylamino)benzaldehyde (Ehrlich's reagent) in a sodium dodecyl sulphate micellar medium is studied. Pyrrole and pyrrole-2-carboxylic acid were used as model compounds for the optimization of the procedure. In the micellar medium with 0.2 M HCl at 90° C, pyrrole reacts in 15 min, whereas a HCl concentration larger than 5 M is required in the absence of the surfactant. The sensitivity increases from 1.3 to 5.6-fold with respect to the use of a non-micellar medium, for some pyrrole derivatives. The procedure is applied to the determination of hydroxyproline in meat samples.

Different mechanisms generating sequence variability are revealed in distinct regions of the hydroxyproline-rich glycoprotein gene from maize and rel…

1992

The sequences of the genes coding for a hydroxyproline-rich glycoprotein from two varieties of maize (Zea mays, Ac1503 and W22), a teosinte (Zea diploperennis) and sorghum (Sorghum vulgare) have been obtained and compared. Distinct patterns of variability have been observed along their sequences. The 500 bp region immediately upstream of the TATA box is highly conserved in the Zea species and contains stretches of sequences also found in the sorghum gene. Further upstream, significant rearrangements are observed, even between the two maize varieties. These observations allow definition of a 5' region, which is common to the four genes and is probably essential for their expression. The 3' e…

Secretion of Protein-bound Hydroxyproline from Moss Callus Cells

1988

Abstract A glycoprotein rich in hydroxyproline was found in wall preparations of callus cells of the moss Physcomitrium pyriforme Brid. It is apparently attached to the non-cellulosic polysaccharides of the wall, and the majority is extractable by boiling the wall fraction or by using a chaotropic salt at room temperature. A pulse-chase technique was used to study the transport of this protein to the wall. Cytochalasin B seems to inhibit its secretion from the callus cells. Some of this wall-associated protein is probably secreted from the cells into the medium. Electron microscopic evidence shows vesicular activity in the cytoplasm and secretion and incorporation into the wall layers (not …

First Chemosensor for Selective Detection and Quantification of L-4-Hydroxyproline in Collagen and Other Bio Samples.

2017

Amino pyridine-based rhodamine conjugate (APR) has been developed as a first chemosensor for selective detection and quantification of L-4-Hydroxyproline (Hyp). The “turn-on” fluorescence property of the chemosensor makes it unique for easy estimation of Hyp in collagen and biological samples. peerReviewed

Ipriflavone prevents radial bone loss in postmenopausal women with low bone mass over 2 years.

1997

Two hundred and fifty-five postmenopausal women with distal forearm bone mineral density (BMD) 1 SD below the mean value for normal age-matched postmenopausal subjects were randomly allocated to a 2-year treatment with oral ipriflavone (200 mg t.i.d.) or a matched placebo, according to a double-masked, parallel-group design. All patients also received a 1 g/day calcium supplement. Distal radius BMD and bone metabolism markers were measured at baseline, and every 6 months. Blood haematology and chemistry and physical parameters were monitored at the same time. One hundred and ninety-six patients completed 2 years of treatment. BMD changes from baseline were analysed according to valid comple…

Skeletal Muscle Collagen Type 1 mRNA, Prolyl-4-Hydroxylase and Hydroxyproline after Prolonged Physical Training in Hypobaric Hypoxia

1994

Regulation of synthesis of fibrillar collagens in rat skeletal muscle during immobilization in shortened and lengthened positions

2001

Immobilization has been shown to cause muscle atrophy and decreased total collagen synthesis in skeletal muscle. These changes can be counteracted by stretch. The purpose of this study was to find out the early effects of immobilization in shortened and lengthened positions on expression of type I and III collagen at pre- and post-translational level. The mRNA levels of type I and III collagen, prolyl 4-hydroxylase activity, total collagen concentration and the proportions of type I and III collagens were analysed in soleus (SOL), gastrocnemius (GM), extensor digitorum longus and tibialis anterior (TA) muscles during immobilization in shortened and lengthened positions for 1, 3 and 7 days. …

Sequential and combined treatment of prolidase deficiency leg ulcers

2010

Background The Authors report a case of chronic cutaneous lesions in a patient affected by prolidase deficiency, a rare disorder inherited through an autosomal recessive gene (50 cases reported ). The enzyme prolidase is widely distributed throughout the body and it is important in the recycling of proline and hydroxyproline. Among the clinical presentations, the most striking manifestation is the skin fragility with leg ulceration (see Table ​Table11) Table 1 Clinical signs of prolidase deficiency The deficiency of the enzyme prolidase is responsible for massive loss of proline in the urine which is estimated to be as high as 3 g/die. The diagnosis is ascertained by iminopeptiduria greater…

Temporary warm ischaemia, 5/6 nephrectomy and single uranylnitrate administration — comparison of three models intended to cause renal fibrosis in ra…

2001

In patients the progression of pathologic renal processes after the treatment of primary disease is a problem of increasing importance and therapeutic strategies are insufficient till now. The aim of this paper was to search for rat models of interstitial fibrosis as a basis for testing therapeutic strategies to prevent end-stage renal failure. Experiments were done on adult female Wistar rats (Han:Wist) to investigate long-term consequences of temporary warm ischaemia, 5/6 nephrectomy (5/6 NX) and single uranyl nitrate (UN) administration (0.3 or 0.5 mg/ 100 g body wt. intraperitoneally). Observation time was 20 weeks after injury in each group. Creatinine clearance, urinary protein excret…