Abnormal formation of collagen cross-links in skin fibroblasts cultured from patients with Ehlers-Danlos syndrome type VI

Ehlers-Danlos syndrome type VI (EDS VI) is an autosomal recessive disorder of connective tissue characterized by hyperextensible, friable skin and joint hypermobility. Severe scoliosis and ocular fragility are present in some patients. This disease is caused by defective collagen lsyl hydroxylase, a vitamin C-dependent enzyme that converts lysyl residues to hydroxylysine on procollagen peptides. Hydroxylysine is essential for the formation of the covalent pyridinium cross-links pyridinoline (Pyr) and deoxypyridinoline (Dpyr), among mature collagen molecules. Pyr derives from three hydroxylysyl residues, whereas Dpyr derives from one lysyl and two hydroxylysyl residues. Patients with EDS VI have high urinary excretion of Dpyr, resulting in a high ratio of Dpyr-Pyr. In this study, we evaluate content and production of pyridinium cross-links in the skin and cultured fibroblasts from patients with EDS VI. The skin of normal controls contained both Pyr and Dpyr, with a marked predominance of Pyr as observed in normal urine. The skin of patients with EDS VI had reduced total content of pyridinium cross-links, with the presence of Dpyr but not Pyr. Long-term cultures of control fibroblasts produced both Pyr and Dpyr, with a pattern resembling that of normal skin. By contrast, cross-links were not detected in dermal fibroblasts cultured from patients with EDS VI. Vitamin C, which improves the clinical manifestations of some patients with EDS VI, decreased Dpyr accumulation though only minimally affecting Pyr content in control cells. By contrast, addition of vitamin C to fibroblasts from patients with EDS VI stimulated the formation of Dpyr more than that of Pyr and greatly increased total pyridinium cross-link formation. These results indicate that qualitative and quantitative alterations of pyridinium cross-links occur in skin and in cultured dermal fibroblasts of patients with EDS VI and may be responsible for their abnormal skin findings. The vitamin C-stimulated production of Dpyr and Pyr in fibroblasts from patients with EDS VI may explain at least in part the therapeutic effects of this vitamin in EDS VI.

Intravenous versus oral calcitriol therapy in renal osteodystrophy: results of a prospective, pulsed and dose-comparable study

Intravenous calcitriol is generally considered to be more efficient than oral administration in the treatment of secondary hyperparathyroidism of chronic renal failure, although a comparative and prospective study employing the same doses and modality of drug administration is lacking. We therefore evaluated 12 hemodialysis (HD) patients (51.7 +/- 9.4 years, mean +/- SD, HD for 8.7 +/- 4.7 years) with marked secondary hyperparathyroidism. Based on basal humoral and bone histologic parameters, we divided these patients into 2 comparable groups. Calcitriol (0.015 micrograms/kg) was given at the end of each dialysis intravenously in group A and orally in group B. Humoral parameters were evaluated basally and after 1, 2, 4 and 8 months. Ax bone biopsy was taken at the start and at the end of the study. From the first month of treatment, group A showed an increment in ionized calcium (from 1.28 +/- 0.08 to 1.37 +/- 0.12 mmol/l, p < 0.01), with a reduction in intact parathyroid hormone (from 470.1 +/- 349.5 to 255.5 +/- 256.5 pg/ml; p < 0.0003) and alkaline phosphatase (from 615.1 +/- 696.3 to 445.3 +/- 577.7 mU/ml, p < 0.001). The occurrence of hypercalcemia prompted a reduction in dialysate calcium content in 4 of 6 patients after 4 months, and of the calcitriol dose in 2 of 4 patients after 6 months. Ionized calcium then turned to 1.32 +/- 0.11 (p = n.s. compared to basal) while the intact parathyroid hormone concentration tended to revert (363.3 +/- 360 pg/ml, p = n.s. compared to basal) and alkaline phosphatase remained low (420 +/- 638 mU/ml, p < 0.0005).(ABSTRACT TRUNCATED AT 250 WORDS)

Two-site immunoradiometric intact parathyroid hormone assay versus C-terminal parathyroid hormone in predicting osteodystrophic bone lesions in predialysis chronic renal failure

Intact parathyroid hormone (iPTH) radioimmunoassay represents an important advancement in the measurement of serum PTH levels, permitting the evaluation of the actual rate of secretion of the parathyroid glands. The aim of the study was to compare the value of intact and C-terminal PTH measurements in predicting the osteodystrophic bone lesion in predialysis patients with chronic renal failure (CRF). We have studied 37 subjects with CRF who were receiving conservative treatment. In each subject a transiliac bone biopsy for histomorphometric examination was performed in addition to the assay of serum intact and C-terminal PTH, osteocalcin, and alkaline phosphatase. Serum C-terminal and intact PTH levels were closely correlated, both showing a high degree of correlation with serum osteocalcin. Similar degrees of correlation were observed between the two PTH assays and the histologic parameters osteoblastic surface (ObS/BS) and osteoclastic surface (OcS/BS). The evaluation of specificity and sensitivity of the two PTH assays in selecting patients with normal or pathologic histomorphometric parameters gave an equivalent number of false positive and negative cases. Based on discriminant analysis of histomorphometric parameters, intact PTH shows a higher discriminant power when compared with C-terminal PTH assay for the parameters OcS/BS and eroded surface (ES/BS), but without practical clinical value. In conclusion, in analogy to the short lived N-terminal PTH fragment assay, prediction of elementary hyperparathyroid bone lesions in predialysis CRF is not improved by the use of intact PTH as compared to the more traditional C-terminal assay.

[Prevalence of some cardiovascular risk factors in a sample of the aged population]

The distribution of some cardiovascular risk factors in a cohort of elderly population is reported. The study population consisted of 427 males aged 71-91, examined in 1991 and belonging to the Italian rural section of the Seven Countries Study on Cardiovascular Diseases. Systolic blood pressure shows an increasing trend with age, with mean levels greater than 160 mmHg in each quinquennium, while the prevalence of hypertension ranges between 60 and 75%. Other risk factors considered such as serum cholesterol, triglycerides, weight, height and smoking habit show decreasing levels with ageing. This trend is clear also for fasting glucose from the age group 76-80.

Biologic effect of 1,24(R)(OH)2D3 versus 1,25(OH)2D3 administration in chronic renal failure

1,24(R)(OH)2D3 is a synthetic analogue of 1,25(OH)2D3 which binds to the same receptors as the physiologic metabolite with a lower affinity. The aim of the present study was to compare the activity of 1,24(R)(OH)2D3 and 1,25(OH)2D3 on several target organs in patients with chronic renal failure. Treatment with 1,24(R)(OH)2D3 at doses of either 1 or 2 micrograms daily was carried out in two groups of 9 patients, with serum creatinine of 4.61 +/- 1.59 and 4.66 +/- 1.46 mg/dl, respectively. Doses of 1,25(OH)2D3 were 0.5 and 1 microgram daily and were administered to 9 and 13 patients, serum creatinine of 4.52 +/- 1.67 and 4.3 +/- 1.16 mg/dl, respectively. Treatment periods were of 2 weeks. Administration of 1,25(OH)2D3, 1 microgram, induced significant increments of intestinal calcium absorption (ICA), ionized calcium, osteocalcin, serum creatinine, urine Ca/GFR, and a decrease in iPTH. 1,25(OH)2D3, 0.5 microgram, induced a significant increase in ICA and osteocalcin and a decrease in iPTH. Similarly 1,24(OH)2D3, 2 micrograms daily, significantly stimulated ICA and raised serum levels of osteocalcin and creatinine while lowering serum iPTH. In addition, 1,24(R)(OH)2D3 administration induced a significant fall of serum 1,25(OH)2D3. Following 1 microgram, only osteocalcin increased. Therefore, the dose of 2 micrograms of 1,24(R)(OH)2D3 has biologic activity similar to 0.5 microgram 1,25(OH)2D3 (4:1). However the activity ratio on osteocalcin production appears to be 2:1. In addition, 1,24(R)(OH)2D3 is able to inhibit renal tubular 1 alpha-hydroxylase. In conclusion 1,24(R)(OH)2D3 may prove to be useful in the treatment of metabolic bone disease.

Procollagen type I C-terminal extension peptide in predialysis chronic renal failure

Collagen type 1 is the most abundant protein of bone. Serum levels of type 1 procollagen carboxy-terminal extension peptide (Procoll-1-C) may give a measure of the rate of synthesis of the collagen of bone and be therefore a marker of bone turnover. We have studied 38 patients with predialysis chronic renal failure; 14 of them were under long-term treatment with 1,25-dihydroxyvitamin D3 [1,25(OH)2D3] for prevention of secondary hyperparathyroidism. In all patients a transiliac bone biopsy for histomorphometry and determination of dynamic parameters was performed following double tetracycline labeling. In addition serum Procoll-1-C, intact and C-terminal parathyroid hormone (PTH), osteocalcin and alkaline phosphatase were determined. In the patients not receiving 1,25(OH)2D3, serum levels of Procoll-1-C were higher than normal. Procoll-1-C did not correlate with any of the humoral parameters, including serum creatinine, nor with static histomorphometric parameters. Contrarily to osteocalcin, the collagen type 1 marker correlated significantly with all dynamic parameters. Treatment with 1,25(OH)2D3 was accompanied by lower levels of osteocalcin, iPTH (n.s.), osteoblastic surface and by normal levels of Procoll-1-C (p < 0.001, compared to untreated patients), without substantial change in bone formation parameters (bone formation rate). In conclusion Procoll-1-C in predialysis chronic renal failure is a marker of bone turnover unparalleled by other markers. 1,25(OH)2D3 administration is associated with lower serum levels of the peptide unaccompanied by a decrement of bone formation parameters, therefore with an apparently better utilization of collagen type 1 in the mineralization process.(ABSTRACT TRUNCATED AT 250 WORDS)

Deferoxamine test and PTH serum levels are useful not to recognize but to exclude aluminum-related bone disease

The use of noninvasive diagnostic tools, like the deferoxamine (DFO) test and serum iPTH, to identify aluminum-related bone disease has proved to be inadequate due to false-negative cases; therefore, bone biopsy becomes a necessary diagnostic procedure. Our purpose was to verify whether these non-invasive parameters, appropriately used, may result valid in the identification of patients not at risk of Al toxicity, therefore restricting the need for histologic evaluation. We studied 68 hemodialyzed patients, aged 49.0 +/- 11.6 years, with a M/F ratio of 37/31 and a dialytic age of 85.0 +/- 47.0 months, by means of bone biopsy, DFO test and serum C-PTH. 19.1% of the cases had positive stainable Al and/or high bone Al content (greater than 60 mg/kg/dw) and could be intoxicated. To obtain the highest sensitivity, we selected the following limit values: the lower limit of increment so far proposed for DFO test positivity (greater than 150 micrograms/l) and a value capable of selecting patients with pathologic osteoclasia for C-PTH (greater than 15 ng/ml). With these limits, four different groups of patients were recognized: group A, DFO test positive and PTH high, n = 12; group B, DFO test positive and PTH low, n = 6; group C, DFO test negative and PTH high, n = 30; group D, DFO test negative and PTH low, n = 20. In group B, which could be anticipated as being at higher risk, we actually found the highest (p less than 0.05) bone Al content as compared to other groups, associated with a reduced bone formation rate.(ABSTRACT TRUNCATED AT 250 WORDS)

Levels of zinc and thymulin in plasma from patients with Crohn's disease

Levels of zinc in plasma from patients with Crohn's disease were significantly lower than those of sex and age matched controls. We also measured the level of plasmic thymulin, a hormone released by the thymus gland, which in its active form binds one zinc molecule. The zinc unbound form of thymulin is biologically inactive and its level in the blood is a very sensitive marker of even marginal zinc deficiency. Levels of active thymulin were significantly reduced in plasma from patients with Crohn's disease, whereas plasma concentrations of the inactive form was higher than in controls. The in vitro addition of zinc ions restored thymulin activity in plasma from patients with Crohn's disease, and induced the disappearance of the inactive form. These findings suggest the existence of a zinc dependent alteration regarding the biological function of thymic hormones in patients with Crohn's disease. Such a defect might explain some of the immunological abnormalities observed in these pathological conditions.

[Clinico-functional evaluation of flunisolide + salbutamol combination (VAL 679/A) vs salbutamol in pediatric patients]

To establish the effectiveness of flunisolide + salbutamol vs salbutamol alone administered by metered aerosol in the phlogistic obstructive diseases, 18 children were evaluated. The treatments were evaluated on the basis of ventilatory function parameters and of tolerance. The results proved positive for all drugs, though the combination flunisolide + salbutamol produced a greater ventilatory and clinical effect.

Osteocalcin, iPTH, alkaline phosphatase and hand X-ray scores as predictive indices of histomorphometric parameters in renal osteodystrophy

To evaluate the relationship between hyperparathyroid bone X-ray lesion, biochemical parameters and bone histology in chronic renal failure, 59 patients (52 +/- 14.9 years; Crs 4.7 +/- 2.2 mg/dl, mean +/- SD) on conservative treatment and 103 (48 +/- 14 years) on hemodialysis (from 48.4 +/- 36.7 months) were studied. Right-hand X-ray was carried out for evaluation of the scores (0-3) of acroosteolysis (score A) and subperiosteal resorption (score B). Serum iPTH, osteocalcin and alkaline phosphatase (AP) were measured. In addition in a subset of 53 patients, 30 in predialysis and 23 in dialysis, a bone biopsy was performed for histomorphometry. In predialysis the scores A and B correlated with bone GLA protein (BGP) (p less than 0.01), AP (p less than 0.05) and osteoid surface (p less than 0.05) and 0.01 respectively). In hemodialysis the same level of significant correlation (p less than 0.001) was found between the scores and the three humoral parameters. Score A correlated with active osteoblastic surface and active resorption surface while score B correlated with active osteoblastic surface (p less than 0.01), osteoid surface and active resorption surface (p less than 0.05). Multiple regression analysis carried out to establish the predictive variables of bone histologic lesions (active resorption surface and active osteoblastic surface) singled out BGP in predialysis and AP and the two scores in dialysis. We conclude that serum BGP, as compared to PTH and AP, prevails as a valid marker of hyperparathyroid bone lesion in predialysis, while in dialysis it does not seem to add further information to that carried by other variables.(ABSTRACT TRUNCATED AT 250 WORDS)

Detection of Lewisaantigen in sera of ovarian carcinoma patients by MOv2-MOv8 double-determinant radioimmunoassay

The monoclonal antibodies MOv2 and MOv8, raised against ovarian carcinoma, were found to be directed against two non-crossreacting epitopes expressed on the same molecule. Immunochemical analysis of the MOv8 recognized epitope showed that the Leaoligosaccharide, or commercial anti-LeaMAb, but not the anti-LebMAb, prevented MOv8 binding to the reference target cell line (SW626), indicating that it is carried by the Leaantigen. Since we previously reported that MOv2 also recognises the Leaantigen, these data suggest that Mov8 and Mov2 were directed against different epitopes on the same oligosaccharide chain. Bearing in mind the knowledge of the biochemical nature of the monoclonal antibody recognized epitopes (CaMOv2 and CaMOv8), the presence of the circulating molecules recognized by them was analyzed by double determinant immunoradiometric assay (DDIRMA) in 103 sera from ovarian carcinoma patients. Patients with clinical evidence of the disease (ED) with MOv2 and MOv8 reactive and negative tumors had sera reactivity in 67% and 19% respectively. Also, 26% of the patients with no clinical evidence of disease (NED) had positive sera. When we investigated the relationship between MOv2-MOv8 DDIRMA sera positivity and red blood cells (RBC) Lewis phenotype, a strong correlation was found between the Lea+phenotype and DDIRMA sera reactivity in healthy donors (6/6) and in ovarian carcinoma patients (9/10) whatever their clinical condition. No Leahealthy donors gave evidence of MOv2-MOv8 reactive sera. In contrast, 33% and 57% of the sera from ED carcinoma patients with respectively Leab+and Leabphenotype were positive.

In conclusion, the percentage of DDIRMA positive cases previously reported in healthy donors and found here in ovarian carcinoma patients with MOv2 and MOv8 negative tumors or NED, was in agreement with Lea +phenotype frequency in the normal Caucasian population. However the Lewisacould represent a tumor-associated antigen in ED patients with Leaphenotype and MOv2-MOv8 DDIRMA might be useful for monitoring the disease

HIV antibody screening and confirmatory testing of Italian blood donors. One-year experience of a reference center

During the first year (1986) of blood donor screening for antibody to HIV, 201,750 subjects were tested in 40 blood banks of Lombardia (Italy). All sera repeatedly positive by ELISA were submitted to our reference center for confirmation by Western blot (WB). Only 40 (0.02%) of 286 repeatedly reactive donors were positive by WB, whereas another 45 (0.022%) gave atypical antibody reactivities on WB, mainly directed against HIV core proteins. Of the 16 donors with inconclusive WB results followed for 4-12 months, 3 developed a full-blown antibody response, 5 maintained the anti-core reactivity throughout the follow-up period, and 8 lost all reactivities. The use of recombinant env and core antigen ELISAs seems to decrease the proportion of sera with inconclusive WB reactions, and to identify as true positive all seroconverting donors in advance of the WB test. The large majority (35 out of 40) of WB-positive donors and all seroconverters for antibody to HIV admitted to belong to a group at risk for AIDS. Among the 19 first-time donors with HIV infection, we found 3 subjects with serological evidence of LAV-2 infection. We describe also the diagnostic and ethical issues when a donor notification policy is based on WB confirmatory procedures.

The antitumor monoclonal antibody MOv2 recognizes the Lewis A hapten

Monoclonal antibody MOv2, produced against ovarian carcinoma, was previously found to bind a carbohydrate epitope (CAMOv2) present on mucins, glycoproteins and a neutral glycolipid. In this paper, the structure of the carbohydrate epitope is determined by immunological reactivity with purified glycolipids and oligosaccharides. Using solid-phase radioimmunoassay and immunostaining of thin layer chromatograms, MOv2 binds strongly to Le(a)-active pentasaccharide ceramide. A smaller neutral glycolipid also weakly binds MOv2. Fifty percent inhibition of binding to Le(a)-active pentasaccharide ceramide is achieved with approximately 8 microM concentration of lacto-N-fucopentaose II (LNF II). Lacto-N-tetraose (LNT) also partially inhibits at about 10(3) times higher concentration suggesting that the faster migrating glycolipid antigen contains this carbohydrate sequence. Binding to Le(a)-active hapten is further confirmed by the specific inhibition of binding by authentic anti-Le(a) monoclonal antibodies but not by anti-Le(b) MOv2 antibody in a serum assay among healthy blood donors also supports these results. In conclusion, we have obtained direct evidence from several independent experiments that antibody MOv2 recognizes the Le(a)-active hapten.

Prognosis of lean and fat hypertensives

A population sample of 1,645 men aged 40-59 at entry examination has been followed up for 25 years. When hypertensives (160 and/or 95 mm Hg or more; n = 432) were divided into fat and lean on the basis of body mass index (cut off at 24.9), the latter group showed a nonsignificant higher risk of dying during the subsequent 25 years (relative risk = 1.15). Univariate and multivariate analyses suggest that among lean people there is an excess of smokers partly explaining the excess risk of lean hypertensives. Both univariate and multivariate analyses also proved that the relationship of fatness-leanness indicators to total mortality is U-shaped and applies to hypertensives as well as to nonhypertensives, and to the whole population. Evidence has been given that changing the definition of fatness-leanness (cutoff of body mass index of 27.9) the relative risk of lean versus fat hypertensives may reverse (0.93). This suggests that a large part of the problem is artificial and should not be tackled without considering the parabolic relationships of indicators of obesity to mortality.

Recent trends in coronary heart disease and other cardiovascular diseases in Italy

Trends in death rates from coronary heart disease (CHD) in Italy in the period 1970-1979 suggest a continuous rising of mortality in males until 1976-1977 followed by a plateau or a slight decrease in the next 2 years; whereas an 11.5% decrease has been observed in females aged 35-74. Looking at the whole group of cardiovascular diseases it appears that a continuous and clear decline in stroke mortality (-14.6% in males and -22.0% in females aged 35-74) explains almost completely the overall decrease of cardiovascular mortality observed during the period 1970-1979 which corresponds to -8.4% in males and -24.3% in females. Limited and unrepresentative data from population samples studied between 1960 and 1980 suggest an increasing incidence of CHD which is compatible with parallel changes of some risk factor levels. In the 1970s a continuous increase of fat consumption and of cigarette consumption has been balanced by an increase of prevalence of controlled hypertensives, by an increase of leisure physical activity, by an increasing availability of coronary care units and consumption of beta-blockers. It is likely that in the late 1970s a plateau was reached in the coronary epidemic.