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1.
Eur Radiol ; 31(3): 1608-1619, 2021 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-32827266

RESUMEN

OBJECTIVES: To analyse the predictive value of the volume of enhancement of disease (VED), based on the CT arterial enhancement coefficient (ΔArt%), in the evaluation of the sorafenib response in patients with advanced hepatocellular carcinoma (HCC). METHODS: Patients with sorafenib-treated advanced HCC, who underwent a multiphase contrast-enhanced CT before (T0) and after 60-70 days of starting therapy (T1), were included. The same target lesions utilised for the response evaluation according to modified Response Evaluation Criteria in Solid Tumors criteria were retrospectively used for the ΔArt% calculation ([(HUarterial phase - HUunenhanced phase) / HUunenhanced phase] × 100). ΔArt% was weighted for the lesion volume to obtain the VED. We compared VEDT0 and VEDT1 values in patients with clinical benefit (CB) or progressive disease (PD). The impact of VED, ancillary imaging findings, and blood chemistries on survival probability was evaluated. RESULTS: Thirty-two patients (25 men, mean age 65.8 years) analysed between 2012 and 2016 were selected. At T1, 8 patients had CB and 24 had PD. VEDT0 was > 70% in 8/8 CB patients compared with 12/24 PD patients (p = 0.011). Patients with VEDT0 > 70% showed a significantly higher median survival than those with lower VEDT0 (451.5 days vs. 209.5 days, p = 0.032). Patients with VEDT0 > 70% and alpha-fetoproteinT0 ≤ 400 ng/ml had significantly longer survival than all other three combinations. In multivariate analysis, VEDT0 > 70% emerged as the only factor independently associated with survival (p = 0.037). CONCLUSION: In patients with advanced HCC treated with sorafenib, VED is a novel radiologic parameter obtained by contrast-enhanced CT, which could be helpful in selecting patients who are more likely to respond to sorafenib, and with a longer survival. KEY POINTS: • To achieve the best results of treatment with sorafenib in advanced HCC, a strict selection of patients is needed. • New radiologic parameters predictive of the response to sorafenib would be essential. • Volume of enhancement of disease (VED) is a novel radiologic parameter obtained by contrast-enhanced CT, which could be helpful in selecting patients who are more likely to respond to therapy, and with a longer survival.


Asunto(s)
Antineoplásicos , Carcinoma Hepatocelular , Neoplasias Hepáticas , Anciano , Antineoplásicos/uso terapéutico , Carcinoma Hepatocelular/diagnóstico por imagen , Carcinoma Hepatocelular/tratamiento farmacológico , Humanos , Neoplasias Hepáticas/diagnóstico por imagen , Neoplasias Hepáticas/tratamiento farmacológico , Masculino , Niacinamida/uso terapéutico , Compuestos de Fenilurea/uso terapéutico , Estudios Retrospectivos , Sorafenib/uso terapéutico , Tomografía Computarizada por Rayos X , Resultado del Tratamiento
3.
Biochim Biophys Acta ; 916(3): 411-8, 1987 Dec 18.
Artículo en Inglés | MEDLINE | ID: mdl-3689800

RESUMEN

In the present paper we report the structural characterization of two genetic mutants of human serum albumin: albumin Vanves, a very rare, electrophoretically fast variant of French origin, and albumin Verona, a slow-migrating variant which is the most frequently observed in Italy and which possesses the same electrophoretic mobility as albumin B. Both variants were isolated from the sera of healthy heterozygous subjects. Analysis of CNBr fragments by isoelectric focusing allowed us to localize the mutation to the COOH-terminal region of the molecule (residues 549-585) in both cases. The modified fragments were then isolated on a preparative scale by HPLC and subjected to tryptic digestion. Sequential analysis of the abnormal tryptic peptide, purified by HPLC, established the mutation responsible for albumin Vanves as 574 Lys----Asn and the molecular defect of albumin Verona as 570 Glu----Lys, both probably due to point mutations in the structural genes. The amino-acid substitutions found in albumins Verona and Vanves are consistent with the electrophoretic mobilities observed for the native proteins at pH 8.6.


Asunto(s)
Albúmina Sérica/genética , Aminoácidos/análisis , Cromatografía Líquida de Alta Presión , Electroforesis en Gel de Poliacrilamida , Humanos , Concentración de Iones de Hidrógeno , Mapeo Peptídico , Albúmina Sérica/análisis
4.
Minerva Stomatol ; 64(6): 309-21, 2015 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-26486205

RESUMEN

AIM: The aim of this study was the clinical and radiological evaluation in severe mandibular atrophy (class V-VI Cadwood-Howell) of bone grafts with homologous fresh frozen bone (FFB) in patients with dysesthesia of the inferior alveolar nerve with or without transposition of the NAI in order to perform a proper implant-prosthetic rehabilitation. METHODS: This article presents our experience in mandibular reconstructions performed in 12 patients with severe mandibular atrophy and dysesthesia performing onlay grafts with FFB and subsequent implant-prosthetic rehabilitation. RESULTS: The surgical protocol of homologous bone graft in symptomatic patients with severe mandibular atrophy presented an excellent clinical outcome with disappearance of dysesthesia in all patients treated, good graft integration and a complete implant-prosthetic rehabilitation with loss of only 3 implants at the 24-36 month follow up visit. CONCLUSION: Homologous bone grafting in patients with severe mandibular atrophy may be a viable therapeutic option in cases of prosthetic reconstruction in those symptomatic patients who cannot tolerate removable dentures, reducing intraoperative time, patient morbidity and the complications in common sites of autologous bone graft removal.


Asunto(s)
Aumento de la Cresta Alveolar/métodos , Trasplante Óseo/métodos , Implantación Dental Endoósea/métodos , Arcada Edéntula/cirugía , Mandíbula/cirugía , Anciano , Aloinjertos , Atrofia , Criopreservación , Femenino , Humanos , Ilion , Masculino , Mandíbula/patología , Nervio Mandibular/cirugía , Persona de Mediana Edad , Transferencia de Nervios , Neuralgia/etiología , Preservación de Órganos , Oseointegración , Parestesia/etiología , Estudios Retrospectivos , Traumatismos del Nervio Trigémino/complicaciones , Traumatismos del Nervio Trigémino/cirugía
5.
Minerva Stomatol ; 64(6): 283-93, 2015 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-26486203

RESUMEN

AIM: Aim of the study was to present a follow-up on 46 cases in which pedical buccal fat pad (BFP) flaps were used to repair oral defects without any additional local flaps or skin grafts. METHODS: The study comprised 46 patients, 31 men and 15 women, with an age range of 30-78 years (mean age 57.3 years). They were treated with a pedicled flap to repair defects of the ipsilateral maxilla (anterior or posterior), soft palate or retromolar mandibular area following tumor resection, osteonecrosis or the closure of oro-antral fistulae. The defects ranged from 2 × 2.5 cm to 4.5 × 5 cm. All patients were treated under general anesthesia. RESULTS: The flap fully covered the intraoral defect with any aesthetic deficits. After one month, the flap was fully epithelialized and of adequate thickness in all cases. Three postoperative complications were reported: one superficial necrosis and two small fistulae. CONCLUSION: Although the BFP has long been recognized and despite the simplicity of preparing the flap itself, numerically significant reports concerning the use of this technique in reconstructive facial surgery have only recently been published. The pedicled buccal fat flap is convenient and reliably repairs oral defects up to 4.5 cm in diameter on the ipsilateral side of the soft and hard palate, posterior alveolar region of the maxilla and the retromolar mandibular area. The surgical procedure is simple and morbidity at the donor site in not significant.


Asunto(s)
Tejido Adiposo/trasplante , Procedimientos Quirúrgicos Orales/métodos , Procedimientos de Cirugía Plástica/métodos , Colgajos Quirúrgicos , Adulto , Anciano , Mejilla/cirugía , Femenino , Humanos , Masculino , Maxilar/cirugía , Persona de Mediana Edad , Neoplasias de la Boca/cirugía , Fístula Oroantral/cirugía , Osteonecrosis/cirugía , Paladar Blando/cirugía , Estudios Retrospectivos
6.
FEBS Lett ; 208(2): 364-8, 1986 Nov 24.
Artículo en Inglés | MEDLINE | ID: mdl-3780972

RESUMEN

Albumin Tagliacozzo is a fast-moving genetic variant of human serum albumin found in 19 unrelated families. The protein was isolated from the serum of a heterozygous healthy subject. Analysis of CNBr fragments by isoelectric focusing allowed us to localize the mutation to CNBr fragment IV (residues 299-329). This fragment was isolated on a preparative scale and subjected to tryptic digestion. Sequential analysis of the abnormal tryptic peptide, purified by RP-HPLC, revealed the variant was caused by 313 Lys----Asn substitution, probably due to a point mutation in the structural gene. The lack of a lysine residue accounts for the electrophoretic behavior of albumin Tagliacozzo.


Asunto(s)
Albúmina Sérica/genética , Secuencia de Aminoácidos , Cromatografía Líquida de Alta Presión , Humanos , Mutación , Fragmentos de Péptidos/análisis , Albúmina Sérica/aislamiento & purificación
7.
FEBS Lett ; 233(1): 100-4, 1988 Jun 06.
Artículo en Inglés | MEDLINE | ID: mdl-2898383

RESUMEN

Albumin Roma is an electrophoretically slow moving genetic variant of human serum albumin found in 22 unrelated families. The protein was isolated from the serum of a healthy, heterozygous subject. Analysis of CNBr fragments by isoelectric focusing allowed us to localize the mutation to fragment CNBr IV (residues 299-329). This fragment was isolated on a preparative scale by RP-HPLC and subjected to tryptic digestion. Sequential analysis of two abnormal tryptic peptides, purified by RP-HPLC, revealed that the variant arises from the substitution of glutamic acid 321 by lysine. This amino acid replacement, probably resulting from a point mutation in the structural gene, causes a change in the net charge of +2 units which is in keeping with the decreased electrophoretic mobility of the native protein.


Asunto(s)
Glutamatos , Lisina , Albúmina Sérica , Secuencia de Aminoácidos , Cromatografía Líquida de Alta Presión , Cromatografía por Intercambio Iónico , Bromuro de Cianógeno , Ácido Glutámico , Heterocigoto , Humanos , Concentración de Iones de Hidrógeno , Focalización Isoeléctrica , Masculino , Mutación , Fragmentos de Péptidos/aislamiento & purificación , Albúmina Sérica/genética , Albúmina Sérica/aislamiento & purificación , Albúmina Sérica Humana , Tripsina
8.
Transplantation ; 26(3): 150-2, 1978 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-705871

RESUMEN

A standardized procedure is proposed for deliberate immunizations against human major histocompatibility complex determinants. The data presented demonstrate its effectiveness and, by using a number of necessary precautions, this procedure has proven to be very safe. The following points are especially important: (1) exclusive utilization of regular blood donors as immunizers; (3) use of whole blood as an immunizing agent; and (3) use of small immunizing stimuli rather than large transfusions. This procedure can be recommended for the production of monospecific anti-HLA antisera and it may be useful if and when a deliberate transfusion policy for prospective kidney recipients is adopted.


Asunto(s)
Transfusión Sanguínea , Inmunización/métodos , Complejo Mayor de Histocompatibilidad , Transfusión Sanguínea/métodos , Femenino , Antígenos HLA , Humanos
9.
Chest ; 98(2): 505-7, 1990 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-2376192

RESUMEN

A case of coronary occlusion occurred seven days after successful percutaneous transluminal coronary angioplasty. The acute complication occurred shortly after a negative exercise stress test and was resolved with intracoronary urokinase.


Asunto(s)
Angioplastia Coronaria con Balón , Enfermedad Coronaria/etiología , Prueba de Esfuerzo/efectos adversos , Terapia Trombolítica , Activador de Plasminógeno de Tipo Uroquinasa/uso terapéutico , Angiografía Coronaria , Enfermedad Coronaria/tratamiento farmacológico , Humanos , Masculino , Persona de Mediana Edad , Factores de Tiempo
10.
Arch Dermatol ; 123(4): 493-9, 1987 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-3827281

RESUMEN

Prolidase deficiency occurred in two sisters suffering from recurrent leg ulcers that appeared in early childhood. The patients presented the typical clinical symptoms of the disease, including characteristic facies, dermatologic manifestations of the lower extremities, splenomegaly, and hematologic anomalies. Large amounts of iminodipeptides were excreted into the urine, and prolidase activity in their erythrocytes was virtually absent. Changes associated with a connective-tissue disorder were demonstrated by light and electron microscopic studies of the patients' apparently normal skin. Collagen fibers were smaller than in controls and were irregularly packed; the fibrils had normal aspect but were significantly smaller than in one age-matched control. Elastin fibers appeared altered both in size and structure.


Asunto(s)
Dipeptidasas/deficiencia , Úlcera de la Pierna/genética , Adulto , Enfermedad Crónica , Colágeno , Elastina , Eritrocitos/metabolismo , Femenino , Humanos , Hidroxiprolina/orina , Úlcera de la Pierna/metabolismo , Úlcera de la Pierna/patología , Piel/patología , Piel/ultraestructura
11.
Coron Artery Dis ; 7(7): 535-40, 1996 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-8913672

RESUMEN

OBJECTIVE: To assess whether and to what extent elective coronary stenting is associated with biochemical evidence of minor myocardial damage (MMD), as defined by the detection of abnormal post-procedural serum levels of one more among the following markers of ischaemic injury: creatine kinase (CK)-MB mass, troponin T (Tn-T) and troponin I (Tn-I). METHODS: Nineteen elective procedure of coronary stenting were compared with a matched group of 25 conventional percutaneous transluminal coronary angioplasty (PTCA) procedures performed in our laboratory from March to June 1995. Cases with evolving or recent (< 2 weeks) myocardial infarction, chronic total occlusions and dilation of saphenous vein grafts were excluded. By definition, all of the patients had undergone uneventful deployment of a single palmaz-Schatz stent, with no chest pain and no persistent ECG changes after the procedure. Serum levels of CK-MB mass, Tn-T and Tn-I were determined at baseline and 6, 12 and 24 h after the procedure. The frequency of abnormal results was determined for each marker. Baseline and peak post-procedural levels in the two groups were compared and related to procedural variables. RESULTS: Baseline values were normal in all cases. The quantitative analysis showed that post-procedural levels of each marker (including total CK) were significantly higher with respect to baseline in both groups. In the stent group, two patients had positive CK-MB mass, four positive Tn-T and seven positive Tn-I. Absolute changes in Tn-T and Tn-I were closely related to changes in CK-MB mass (r = 0.76, P < 0.0001; r = 0.90, P < 0.0001), respectively). Three of these patients developed clinically silent side-branch occlusion. All of them were positive for troponins and two were positive for CK-MB. No correlation was found between procedural variables and the results of biochemical assays. In the PTCA group, three patients were positive for Tn-I, whereas the CK-MB mass and Tn-T remained constantly normal. No side-branch occlusion was observed. The peak CK-MB mass and Tn-I were significantly higher in the stent group than they were in the PTCA group (3.04 +/- 4.1 versus 1.27 +/- 1.3 ng/ml, P = 0.046; 0.78 +/- 1.17 versus 0.28 +/- 0.3 ng/ml, P = 0.046, respectively). This difference was no longer apparent when patients with side-branch occlusion were excluded. CONCLUSIONS: In our series, Tn-I measurement shows the highest ability to detect MMD, being positive in 37% of stent and 14% of PTCA cases. Elective coronary stenting associated with greater release of CK-MB mass and Tn-I than is conventional PTCA. This finding is mainly determined by cases of side branch occlusion, which account for most, but not all, periprocedural MMD in the stent group.


Asunto(s)
Enfermedad Coronaria/sangre , Enfermedad Coronaria/terapia , Creatina Quinasa/sangre , Stents , Troponina I/sangre , Troponina/sangre , Adulto , Anciano , Angioplastia Coronaria con Balón , Biomarcadores/sangre , Angiografía Coronaria , Enfermedad Coronaria/fisiopatología , Femenino , Humanos , Isoenzimas , Masculino , Análisis por Apareamiento , Persona de Mediana Edad , Troponina T
12.
Perit Dial Int ; 13 Suppl 2: S254-6, 1993.
Artículo en Inglés | MEDLINE | ID: mdl-8399581

RESUMEN

During the period 1986-1991, 140 pediatric patients [age < or = 15 years at the start of chronic peritoneal dialysis (CPD)], belonging to 15 dialysis centers, were enrolled in the Italian Registry of Pediatric Chronic Peritoneal Dialysis. Data on 188 peritoneal catheters were collected: 161 catheters were Tenckhoff (144 double-cuff, 17 single-cuff), and 27 were two-cuff Valli-type catheters. All catheters were surgically inserted; the entry site was in the midline in 84 cases and paramedian in 104. An omentectomy was performed in 78.8% of the cases. Apart from peritonitis, there were 161 catheter-related complications (103 exit-site infections, 17 leakages, 15 obstructions, 15 outer-cuff extrusions, 5 hemoperitoneum, 6 others) observed during 2687.5 dialysis-months, with an incidence of one complication every 16.7 dialysis-months. Fifty-five catheters (29.2%) were removed; infection (39 cases) was the main cause for removal, followed by obstruction (9 cases), dislocation, and outer-cuff extrusion (2 cases each). Actuarial survival of all catheters was 79.7% at 1 year, 66.6% at 2 years, 42.8% at 3 years, and 39.8% at 4 years. No difference in catheter survival was observed according to the entry site. When considering the age of the patients at catheter insertion, a difference close to statistical significance was found (p = 0.06).


Asunto(s)
Catéteres de Permanencia/efectos adversos , Diálisis Peritoneal/efectos adversos , Análisis Actuarial , Adolescente , Niño , Preescolar , Humanos , Lactante , Infecciones/etiología
13.
Ital J Biochem ; 28(3): 163-72, 1979.
Artículo en Inglés | MEDLINE | ID: mdl-553900

RESUMEN

In the present paper a relatively rapid and simple method for estimating the ratio of collagen type III to type I in soft tissues is proposed. The ratio Gly/Ala is determined in pure collagen samples obtained from pepsin digests of the tissues. Since this ratio varies linearly depending on the composition of the mixtures of the two collagen types, it is shown that the percentage content of the two collagen types is easily calculated.


Asunto(s)
Colágeno/análisis , Piel/análisis , Adulto , Aminoácidos/análisis , Electroforesis en Gel de Poliacrilamida , Humanos , Recién Nacido , Pulmón/análisis , Métodos
14.
Ital J Biochem ; 33(2): 117-27, 1984.
Artículo en Inglés | MEDLINE | ID: mdl-6735684

RESUMEN

Hydroxylysine diglycoside was prepared from hydrolyzed sponge by a combination of ion-exchange chromatography and gel filtration. The product obtained was chemically pure on amino acid analyzer and was active as substrate of the enzyme alpha-(1----2)glucosidase. Hyl monoglycoside was prepared by mild acid hydrolysis from diglycoside. A reverse phase HPLC system was devised for Hyl glycosides, hydroxylysine and other basic amino acids. The separation was achieved using an octadecyl bonded silica column on the compounds derivatized with dabsyl chloride to produce di-dabsyl derivatives. Elution was followed in the visible region at 436 nm. In the conditions used no or very low amount of mono-dabsyl derivatives was observed. Hyl di- and monoglycoside resulted a mixture of two diastereoisomers, which form during the alkaline hydrolysis. The separation of the diastereoisomers of each compound depended on pH and ionic strength of the eluent in the HPLC column, whereas they were not separated by our short column on amino acid analyzer. The HPLC system was also used for the analysis of Hyl glycosides on two collagen preparations.


Asunto(s)
Hidroxilisina/análogos & derivados , Animales , Cromatografía Líquida de Alta Presión/métodos , Hidroxilisina/síntesis química , Hidroxilisina/aislamiento & purificación , Microquímica , Poríferos , Relación Estructura-Actividad
15.
Ital J Biochem ; 29(5): 337-50, 1980.
Artículo en Inglés | MEDLINE | ID: mdl-7203991

RESUMEN

Urinary GAGs from patients affected with Osteogenesis Imperfecta (O.I.) type I, type II and type III - according to Sillence et al. (1979) - have been investigated. Galactosamine to glucosamine ratio resulted significantly decreased in O.I. type II and III, whereas smaller differences in the mildest type of the disease were observed. Cellulose polyacetate electrophoresis of urinary GAGs purified from some patients showed the presence of a slowly moving polysaccharide substance, which did not appear in normal subjects. Moreover some pathological fractions, mainly constituted of ChS on the basis of chemical analysis and electrophoretic behaviour, were not digested by testicular hyaluronidase and presented anomalous structures as compared with the corresponding normal ones. These results seem to indicate that in some forms of O.I. the metabolic defect(s) not only affects the synthesis or the catabolism of a particular type of collagen, but also involves the proteoglycan component of the connective tissue.


Asunto(s)
Glicosaminoglicanos/orina , Osteogénesis Imperfecta/metabolismo , Adolescente , Adulto , Amino Azúcares/análisis , Animales , Bovinos , Niño , Preescolar , Condroitín Liasas , Cromatografía por Intercambio Iónico , Humanos , Hialuronoglucosaminidasa , Lactante , Osteogénesis Imperfecta/orina , Ácidos Urónicos/análisis
16.
Ital J Biochem ; 32(6): 418-30, 1983.
Artículo en Inglés | MEDLINE | ID: mdl-6373663

RESUMEN

Hydroxylysine (Hyl) glycosides were determined both on the collagen produced by in-vitro cultures of human skin fibroblasts and pig articular chondrocytes and on the insoluble collagen extracted from bovine cornea and sclera. The disorganized collagen present in the culture medium showed a Hyl di- to mono-glycoside ratio markedly higher than the molecules extracted from the cell layer, where electron microscopy investigations demonstrated the real presence of collagen fibres. Moreover in bovine cornea the insoluble collagen showed a ratio Hyl di- to mono-glycoside significantly higher than in sclera, which, on the contrary, possesses fibres with larger mean diameter. The possible conversion of Hyl diglycoside to monoglycoside was suggested by the demonstration of an alpha (1----2) glucosidase activity on Hyl diglycoside , in an enzyme extract from cultured human skin fibroblasts. A role for the processes of collagen glycosylation and deglycosylation was thus considered.


Asunto(s)
Cartílago/ultraestructura , Colágeno , Glicósidos/análisis , Animales , Animales Recién Nacidos , Fenómenos Químicos , Química , Córnea/análisis , Fibroblastos , Porcinos , alfa-Glucosidasas/análisis
17.
Ital J Biochem ; 36(4): 256-66, 1987.
Artículo en Inglés | MEDLINE | ID: mdl-3429209

RESUMEN

A case of severe non-lethal Osteogenesis imperfecta was studied. The patient's cultured skin fibroblasts synthesised a mixed population of type I collagen chains some of which showed abnormal behaviour on sodium dodecyl sulfate-polyacrylamide gel electrophoresis. Further analysis revealed that two types of alpha 1(I) chains were synthesised, both an abnormal, slower migrating and a normal species. A small defect in one allele of one of the type I procollagen chains could lead to the larger size of the abnormal chains, probably caused by overmodifications of the triple helical region. CNBr peptide mapping allowed us to localise the defect midway along the triple helix: the defect site could be assigned to the region between the alpha 1(I)CB-3 and CB-7 peptides. The abnormal alpha 1(I) chains synthesised by the patient's cells had a melting temperature which was about 2 degrees C lower than normal chains. The results appear to be in agreement with the defect localisation and the phenotype.


Asunto(s)
Fibroblastos/metabolismo , Osteogénesis Imperfecta/metabolismo , Procolágeno/análisis , Aminoácidos/análisis , Niño , Colágeno/análisis , Colágeno/biosíntesis , Humanos , Masculino , Osteogénesis Imperfecta/genética , Mapeo Peptídico , Procolágeno/biosíntesis , Procolágeno/genética
18.
Ital J Biochem ; 35(5): 296-303, 1986.
Artículo en Inglés | MEDLINE | ID: mdl-3804697

RESUMEN

Kinetic parameters and regulatory properties of UDPGDH extracted from cultured human skin fibroblasts were determined and compared with those of UDPGDH from cornea and epiphysial-plate cartilage. Fibroblast enzyme showed an affinity for UDPG 7 times higher than cartilage enzyme and 42 times higher than cornea enzyme. UDP-xylose acted as a co-operative allosteric inhibitor, but under the same experimental conditions fibroblast enzyme was significantly less inhibited. These results were in agreement with the different GAG production of the cells we studied. Fibroblast UDPGDH activity was regulated by the NAD/NADH ratio and it was also affected by modifications of extracellular matrix composition. A significant increase of UDPGDH affinity for UDPG was observed after the treatment of the monolayers with Chase ABC.


Asunto(s)
Fibroblastos/metabolismo , Uridina Difosfato Ácido Glucurónico/biosíntesis , Azúcares de Uridina Difosfato/biosíntesis , Células Cultivadas , Condroitín Liasas/farmacología , Fibroblastos/efectos de los fármacos , Glicosaminoglicanos/metabolismo , Humanos , Concentración de Iones de Hidrógeno , Cinética , NAD/farmacología , Piel/citología , Uridina Difosfato Ácido Glucurónico/fisiología , Uridina Difosfato Xilosa/farmacología , Ácidos Urónicos/biosíntesis
19.
Ital J Biochem ; 38(5): 360-8, 1989.
Artículo en Inglés | MEDLINE | ID: mdl-2632462

RESUMEN

UDP-glucose dehydrogenase (UDPGDH) was extracted and partially purified from different rat tissues and the kinetic parameters and some properties of the enzyme were determined and compared. The pH optimum ranged between 8.6 and 9.4 for liver and kidney UDPGDH and between 8.4 and 8.6 for skin and lung UDPGDH. Liver and kidney enzymes showed a similar affinity for both UDPG and NAD. Lung and skin enzymes also showed similar affinity for both substrates, which differed however from that of liver and kidney UDPGDH. Both liver and kidney enzymes had a higher heat stability and a different electrophoretic mobility compared to skin and lung UDPGDH. These data suggest the existence of different tissue specific forms of the enzyme.


Asunto(s)
Deshidrogenasas de Carbohidratos/análisis , Glicosaminoglicanos/biosíntesis , Isoenzimas/análisis , Uridina Difosfato Glucosa Deshidrogenasa/análisis , Animales , Electroforesis en Acetato de Celulosa , Estabilidad de Enzimas , Femenino , Calor , Concentración de Iones de Hidrógeno , Especificidad de Órganos , Ratas , Ratas Endogámicas
20.
Ital J Biochem ; 33(6): 403-12, 1984.
Artículo en Inglés | MEDLINE | ID: mdl-6526643

RESUMEN

The PGs produced in the growth medium by skin fibroblast cultures from two O.I. affected patients were investigated. After density gradient centrifugation, in the most dense fraction two main families of molecules appeared. The patient with the more severe clinical picture showed a lower content of the PGs with the highest molecular weight. The GAG composition of PGs was different in the two patients. The more severely affected one showed an increase of HS and a decrease of ChS content, in agreement with the lower value of galactosamine to glucosamine ratio in urinary GAGs.


Asunto(s)
Osteogénesis Imperfecta/metabolismo , Proteoglicanos/metabolismo , Células Cultivadas , Centrifugación por Gradiente de Densidad , Preescolar , Medios de Cultivo , Fibroblastos/metabolismo , Humanos , Concentración de Iones de Hidrógeno , Lactante , Masculino , Piel/metabolismo
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