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Biomedical subjects

R Coppola

Publications and source records attributed to R Coppola.

At least 163 records · Page 9Linked to original sources
PubMed1984

Passive-active immunoprophylaxis in newborns to HBsAg carrier mothers liguria--I.

Thirty neonates to HBsAg carrier mothers, two of whom were HBeAg positive, received passive-active immunoprophylaxis. Within 48 hours after birth and at the first month of life these newborns were given HBIG (0.5 ml/Kg) and at the third month of life they were given first vaccination (10 micrograms). "HB-Vax" (M.S.D.) has been employed and its schedule has been performed (2 degrees and 3 degrees injections respectively at 4th and 9th month of life). Blood specimens have been collected in infants at birth and at each HBIG and vaccine administration, two months after the 2nd vaccination, one and six months after the third one. All specimens have been tested for HBV markers: HBsAg, anti-HBs, anti-HBc, anti-HBe and anti-HBc IgM. The anti-HBs titration has been performed according to WHO International Reference anti-HBs Standard. ALT and AST levels were determined in all infants specimens. The newborns did not show clinical signs or lab tests expressing HBV infection during the follow-up period. The anti-HBs geometric mean titres have been the following: 125 mIU/ml at 1 month, 176.4 mIU/ml at 3 months, 64.4 mIU/ml at 4 months, 119 mIU/ml at 6 months, 321 mIU/ml at 9 months, 2580.8 mIU/ml at 10 months and 715.3 mIU/ml at 15 months of life. Finally, side effects were observed for no infants.

Adult↗
PubMed1983

99mTc-diethyl-IDA: the extraction efficiency of the liver.

The extraction efficiencies of the liver were studied in rabbits by injection in the portal vein of 99mTc-IDA and 131I-Rose Bengal in two experimental conditions. In the first experiment blood samples were collected for one minute from a catheter inserted into the vena cava with the tip at the sovrahepatic veins outflow level. The vena cava was ligated upperstream. In the second experiment blood was collected from the general circulation every other minute for 20' after administration. Control experiments were performed in rabbits by administration of 99mTc-Pertechnetate and 99mTc-Albumin. The results showed that the extraction of diethyl-IDA from the blood flowing through the liver is almost total.

Animals↗
PubMed1983

Rupture of multiple hepatic adenoma and oral contraceptive use: a case report.

A 38-year-old woman was seen with a hemoperitoneum caused by rupture of a hepatic adenoma of the right lobe. The patient had been taking oral contraceptives for ten years, but discontinued their use three years previously. During the postoperative course a second adenoma of the contralateral lobe, not diagnosed at the first operation, ruptured. The relationship between oral contraceptive use and hepatic cell adenoma is briefly reviewed.

Adenoma↗
PubMed1982

Computer generation of surface distribution maps of measures of brain activity.

A laboratory computer system in described which will rapidly generate gray-scale maps showing the distribution of measures derived from the electrical activity of the brain, such as the electroencephalogram (EEG) or other biological measures. The system allows flexible description of electrode number and placement, mapping onto any shaped space and rapid generation of maps by integration with the data collection software.

Brain↗
PubMed1982

A new system for gray-level surface distribution maps of electrical activity.

This report describes an integrated anatomical, electrophysiological and data management system for presenting cortical surface distribution maps. Approximately equal area projections (lateral and top) were constructed from a cross-sectional whole head atlas. Anatomical landmarks (major sulcus and gyrus locations) were also located on the outline. The outline and weights for interpolation are stored in the computer, with software for map generation directly from multilead EEG or evoked potential data. Electrode position and number can be easily varied and mapped onto any shaped space using the same program. Data derived from other sources such as xenon blood flow, brain scans or positron emission tomography can similarly be presented. The program uses a laboratory computer and emphasizes simplicity of data management and a mapping algorithm which is applicable to many forms of data.

Brain↗
PubMed1982

The role of the spleen in regulating the plasma levels of factor VIII--von Willebrand's factor after DDAVP.

Organ transplantation and perfusion studied indicate that the spleen plays an important role in the regulation of plasma levels of factor VIII-von Willebrand's factor (FVIII-vWF). To better understand the mechanisms that regulate the FVIII-vWF increases after infusion of 1-deamino-8-D-arginine vasopressin (DDAVP), we have measured factor VIII coagulant activity (FVIII:C) and antigen (FVIII:CAg) and von Willebrand's factor antigen (vWF:Ag) and ristocetin cofactor (vWF:RCof) in 9 asplenic subjects with normal baseline concentrations, in 7 asplenic subjects with high concentrations, and in 14 normal controls with intact spleens. In "normal" aasplenics, all the FVIII-vWF-related measurements increased significantly over baseline values, indicating that responsiveness to DDAVP is not abolished by splenectomy. The maximal vWF:Ag and vWF:RCof responses were no different from those of normal controls, suggesting that DDAVP releases vWF from storage sites other than the spleen. The FVIII:C response was significantly lower than in normal controls, but FVIII:CAg did not differ, making FVIII:CAg higher than FVIII:CAg in "normal" asplenics. These findings suggest that the spleen, rather than being a storage site for FVIII, is the organ in which a partially inactive form of FVIII acquires full coagulant activity. In "high" asplenics, all the FVIII-vWF-related measurements increased less than in "normal" splenics, indicating that long-term elevations of plasma concentrations of FVIII-vWF are accompanied by decreased release from those storage pool(s) mobilized by DDAVP.

Adolescent↗
PubMed1982

Topographic cortical mapping of EEG sleep stages during daytime naps in normal subjects.

Computer-generated cortical maps of power spectral estimates derived from 16 leads were drawn based on daytime sleep recordings in four normal volunteers. These data were compiled from nine 10-s artifact-free, EEG epochs from awake, stages 1-4 and REM sleep in each volunteer. EEG leads were placed on the left hemisphere and midline according to the 10-20 system with four additional interpolated posterior locations. Magnitude spectral estimates with 1 Hz resolution and adjacent frequencies (delta 2-4, alpha 8-12, beta 13-18) were analyzed with two-way ANOVA (lead by sleep stage). Delta activity was relatively uniform and of low amplitude in awake, eyes-closed subjects, and REM. Delta power increased at the vertex in stage 1. With progressing, non-REM sleep stages, it increased in power and enlarged radially to the intraparietal sulcus posteriorly, and the superior frontal gyrus anteriorly. Comparison of maps with ear and a computed average reference yielded similar topographic patterns. Alpha activity was expectedly maximal occipitally in awake subjects, but surprisingly a frontal area appeared in slow wave sleep. Beta activity in awake subjects was low and maximal parietally; stages 1 and REM showed even lower and more uniform distribution. Stage 2 showed the greatest power, concentrated at the vertex, with stages 3 and 4 diminishing. These data suggest that sleep stages are not completely uniform electrophysiologically across the cortex. This opens the possibility for a new method for the diagnosis of sleep disorders and alternatives in sleep staging.

Adult↗
PubMed1981

Somatosensory evoked potentials during whole body hyperthermia in humans.

Somatosensory evoked potentials (SEPs) and body temperature were recorded in patients subjected to induced total hyperthermia for treatment of advanced neoplasms. Elevation of body temperature up to 42 degrees C for 2 h was achieved using a computer-controlled external heating system. SEPs were recorded continuously on-line during the treatment using finger shock stimulation. Evoked potential components later than 160 msec disappeared in the early part of the treatment, but reappeared quickly during cooling. P50 and P50-N70 amplitudes decreased regularly and significantly over the whole duration of the heating period. During the plateau period, no evoked potential peaks could be detected but short latency peaks reappeared as soon as cooling started. The disappearance of SEPs to finger stimulation during sustained hyperthermia at 42 degrees C confirms the findings obtained by EEG recording that a major neuronal dysfunction occurs under these circumstances which subsides quickly as temperature is dropped.

Body Temperature↗
PubMed1981

Alterations of factor VIII von Willebrand factor in clinical conditions associated with an increase in its plasma concentration.

Factor VIII-related antigen (VIIIR:Ag) was consistently higher than factor-VIII procoagulant activity (VIII:C) in 57 patients with clinical conditions characterized by acute-phase reactions. Two different methods for measuring VIII:C (one- and two-stage assays) and VIIIR:Ag (electroimmunodiffusion and immunoradiometric assay) gave concordant results in the majority of cases. In 43% of plasma samples, crossed immunoelectrophoresis in agarose gel was characterized by the appearance of an additional, fast-moving precipitin peak which was immunologically identical with the major, slower-moving VIIIR:Ag peak. The fast-moving peak was detected in all the patients with clinical conditions typically associated with increased plasma proteolysis (DIC, acute pancreatitis, during thrombolytic therapy). It was present in a smaller proportion of cases with liver and renal failure and malignancies and in the post-operative period. The additional VIIIR:Ag peak is thought to be the result of in vivo factor VIII/von Willebrand factor fragmentation by proteolytic enzymes.

Antigens↗
PubMed1981

Factor VIII/von Willebrand factor in glomerular nephropathies.

Levels of factor VIII/von Willebrand factor were measured in 105 patients affected by glomerulonephritis either of primary origin or associated with systemic diseases. The median plasma concentration of factor VIII-related antigen was significantly higher in the patients than in healthy controls. Amongst patients with primary glomerulonephritis, higher levels were observed in minimal change nephropathy than in other types. In patients with secondary glomerulonephritis, plasma factor VIII-related antigen was particularly elevated in lupus nephritis and in renal amyloidosis. Altogether, patients with the nephrotic syndrome showed higher levels than patients with lesser degrees of proteinuria. A negative correlation was found between the plasma concentration of factor VIII-related antigen and that of serum albumin but no correlation was observed with the extent of proteinuria. In 48 patients, plasma factor-VIII procoagulant activity was also measured and found to be elevated to the same extent as factor VIII-related antigen in the majority of cases. The urinary excretion of factor VIII-related antigen, evaluated in 72 patients, was found in variable amounts in 31 cases without any correlation with proteinuria. Glomerular deposits of factor VIII-related antigen were an uncommon finding. After 24 months, there was no clear evidence of an unfavourable association between increased plasma levels of factor VIII-related antigen and the course of the disease. Our findings suggest that the measurement of levels of factor VIII/von Willebrand factor in plasma or urine must be interpreted with caution in predicting the clinical course of patients affected by glomerular disease.

Antigens↗
PubMed1980

Mutagenicity and toxicity of chromyl chloride and its vapours.

Chromyl chloride (CC), a liquid Cr6+ compound suspected of carcinogenic activity, was assayed for mutagenicity in the Ames reversion test. Due to its high volatility and toxic and corrosive properties, handling of CC required particular precautions. The liquid phase of CC elicited dose-related mutations in Salmonella typhimurium, strain TA100, although it had a limited range of activity because of its toxicity to the bacteria. The mutagenic potency and the toxic activity were of the same order of magnitude as all the water-soluble Cr6+ compounds so far tested. Toxic and mutagenic activities could also be clearly detected by using a variety of modifications of the Ames test in CC vapours which indicates the particular danger of this chromium compound. In analogy with the other Cr6+ compounds previously tested in this laboratory, all the effects observed were decreased in the presence of S-9 mix containing rat liver post-mitochondrial fractions.

Chlorides↗
PubMed1979

Urinary excretion of factor VIII after renal transplantation.

The urinary excretion of factor-VIII-related antigen (VIIIRAg) was measured in 72 patients with kidney transplants and compared with that of two end-products of fibrin-fibrinogen lysis (fragments D and E) to assess their usefulness in monitoring the onset of rejection episodes. Specific and sensitive radioimmunoassays were used to measure the three proteins. Unconcentrated urine samples of 24-hour collections were obtained from 20 healthy subjects, 48 patients with stable transplants, and 24 patients with recent transplants serially followed up from the day of transplantation. Factor VIIIRAg and fragments E and D were not detectable in the urine from healthy subjects but were present in 39%, 60%, and 100% respectively of samples from patients with stable transplants. During 33 acute rejection episodes in 19 patients with recent transplants factor VIIIRAg and fragments E and D were significantly increased above the values observed in patients with stable transplants in 82%, 73%, and 64% of samples respectively; in patients with recent transplants showing no clinical sign of rejection increased excretion of these proteins was observed in 11%, 26%, and 22% of samples respectively. The presence of factor VIIIRAg in urine from patients with kidney allografts suggests that endothelial cell-factor VIII-platelet interactions might pay a key part in the pathogenesis of acute rejection. The results suggest that the assay of factor VIIIRAg in urine is more useful than assays of fragments D and E as a corroborative index of transplant rejection.

Antigens↗
PubMed1979

Isolating low frequency activity EEG spectrum analysis.

A method for isolating and removing very slow activity from EEG records prior to spectrum computation is presented. This is accomplished by an autoregressive filter whose frequency transfer characteristic can be easily controlled. Examples of spectra computed for various filter parameter values are shown.

Computers↗
PubMed1979

Reversal of sodium-azide mutagenicity by liver preparations and by gastric juice.

Sodium azide was found to be mutagenic for Salmonella typhimurium by inducing base-pair substitutions that were not enhanced by pKM101 plasmid (R factor). However, the mutagenicity of sodium azide was decreased by enzyme proteins contained in rat-liver post-mitochondrial fractions, depending on the NADPH-generating system. Pre-incubation with human gastric juice also decreased azide mutagenicity. These metabolic effects might explain the conflicting nature of the mutagenicity and carcinogenicity tests reported in the literature. Laboratory reagents containing 0.1% sodium azide as a preservative showed the expected patterns of mutagenicity and of metabolic deactivation, and no aspecific interaction could be detected between azide and the various components, including proteins, of the reagents tested.

Animals↗
PubMed1978

Signal to noise ratio and response variability measurements in single trial evoked potentials.

Techniques were developed for measurement of signal to noise ratio and response variability in single trial evoked potentials. These techniques were extended and verified using a digital computer simulation of signal plus noise trials. When applied to real data the measures appear to have high reliability and to demonstrate that human evoked potentials are more variable than would be expected from background noise variation alone. Empirical equations are presented which can be applied to existing single trial EP data to estimate both signal-to-noise ratio and its expected variance.

Adult↗