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V Rizzo

Publications and source records attributed to V Rizzo.

89 records · Page 5Linked to original sources
PubMed1976

[Neuroblastoma. Clinical aspects and therapy].

A general account of questions relating to neuroblastoma is followed by the presentation of 53 personal cases observed between 1955 and 1974. Appraisal of the salient data offers information relating to prognosis and treatment in line with the more extensive series presented in the U.S. literature and elsewhere. Cases diagnosed and treated in the first year of life have a distinctly encouraging prognosis. It is felt that accurate clinical, radiological and laboratory screening should be relied upon in individual cases to decide whether or not surgical management is indicated, whereas the high rate of intra- and post-operative mortality would seem to militate against the resort to desperate attempts to achieve total extirpation, accompanied by damage to essential structures, especially since the pratical results achieved are no more than comparable with those offered by conservative surgery. It is hoped that a strip test suitable for use in routine practice will be evolved, bearing in mind the peculiar features of neuroblastomas.

Abdominal Neoplasms↗
PubMedDate not supplied

Fractionation and characterization of a conjugate between a polymeric drug-carrier and the antitumor drug camptothecin.

A conjugate between the antitumor drug camptothecin and the polymeric drug-carrier poly[N-(2-hydroxypropyl)methacrylamide] was synthesized and fractionated. The conjugate samples, both fractionated and unfractionated, were characterized with a multi-detector SEC system using three on-line detectors: a multi-angle light scattering photometer, a viscometer, and a refractometer. The used mobile phase (DMF + 0.01 M LiBr + 0.05 M CH(3)COOH) derives from previous experience with similar conjugates. Narrow molar mass distribution fractions of the conjugate obtained by means of a semipreparative LC system were used to derive the coefficients of the Mark-Houwink-Sakurada relationship and to check the universal calibration of the SEC system. This study has demonstrated that the conjugate elutes according to the hydrodynamic volume. Thus, a conventional SEC method that uses only an on-line refractometer detector, commercially available narrow standards, and the universal calibration is adequate for the characterization of the molar mass distribution. Also the size and the conformation of the conjugate were studied by means of the gyration radius-molar mass power law.

Antineoplastic Agents↗
PubMedDate not supplied

Characterization of small combinatorial chemistry libraries by (1)H NMR. Quantitation with a convenient and novel internal standard.

A novel silane standard, 1,4-bis(trimethylsilyl)benzene (BTMSB), is introduced for the generic quantitation of small organic molecules in DMSO-d(6) solution by (1)H NMR. This standard is an easily weighable solid and is stable for at least 1 month in DMSO solution, and its (1)H NMR spectrum contains a strong singlet in a region usually free of signals. With a set of certified standards, concentration determination with about 2% precision and accuracy is verified after solution preparation with fully automated procedures, thus making very effective the characterization of small combinatorial chemistry libraries for identity and purity when combined with other physicochemical or biochemical tests. As an example, for a set of about 400 compounds, results of (1)H NMR characterization are compared to the more customary LC-UV-MS method. NMR and MS data agree for identity on the vast majority of cases (84% positive and 5% negative), whereas the remaining cases (11%) are marked as highly impure only after NMR spectra analysis. Most importantly, determination of concentration rather than that of relative purity appears the right choice for a correct evaluation of biochemical potency.

Chromatography, High Pressure Liquid↗
PubMedDate not supplied

Microvascular permselectivity in the chick chorioallantoic membrane during endothelial cell senescence.

The chorioallantoic membrane (CAM) of the chick embryo represents an in vivo model to evaluate microvascular function during the sequential phases of endothelial proliferation (angiogenesis), cytodifferentiation, and senescence. The principal focus of this study was to characterize microvascular barrier functions of the CAM endothelium during its nonproliferating, aging phase (senescence). A graded series of fluorescein isothiocyanate (FITC) dextrans served to index macromolecular selectivity of the senescent capillary endothelium. Extravasation of FITC dextrans 40 and 150 was restricted, while FITC dextran 10 progressively accumulated within the intercapillary interstitia during 15-min perfusion periods. Endothelial vesicle densities were greater in the first- and second-order pre- and first- order postcapillary endothelia (28 +/- 8/micron2) than those recorded for the capillary endothelium (8 +/- 3/micron2). Junctional cleft lengths (luminal to abluminal distances), on the other hand, were greater in the capillary endothelium (1.08 +/- 0.50 microns) than those recorded for the second-order pre- and postcapillaries (0.46 +/- 0.03 micron). Junctional cleft widths were segmentally uniform (20 nm) in the microvascular units. That permselectivity of the segmental microvascular endothelia was homogeneous is ultrastructurally consistent with the uniform junctional cleft widths rather than the heterogeneous cleft lengths and vesicle densities. The CAM serves as the principal respiratory exchange surface of the embryo. Thus, maintenance of colloid oncotic balance across the microvascular endothelium is likely critical to gaseous exchange. The retention of a selective barrier during the senescent phase of the CAM endothelium serves to support this concept.

Allantois↗
PubMedDate not supplied

Interleukin-2 receptor positive cells and circulating soluble interleukin-2 receptors in patients with solid tumors are not correlated.

Activated lymphocytes can release a soluble form of IL-2 receptor (sIL-2R), which retains the capacity to bind IL-2. Abnormally high values of sIL-2R have been observed in patients with advanced solid tumors. In an attempt to further understand the biological significance of sIL-2R in solid tumors, this study investigated the relation between sIL-2R and Tac-positive cells. sIL-2R serum levels and Tac-positive cells were determined in 18 patients with solid tumors metastatic, 108 non-metastatic. Tumor types were: breast 7; lung 6; colon 2; stomach 1; testis 1; larynx 1. No correlation was found between circulating sIL-2R values and Tac-positive cells, and there was no difference between Tac-positive cell mean number in patients with high and normal sIL-2R levels. These preliminary results suggest that different mechanisms are responsible for sIL-2R release in the blood and IL-2 receptor expression on the immune cell surface.

Adult↗
PubMedDate not supplied

Morbidity and mortality associated with vasopressin replacement therapy in children.

OBJECTIVE: To assess the incidence and associated risk factors of adverse reactions of DDAVP treatment of children with diabetes insipidus, comparing different routes of administration. DESIGN: We retrospectively studied 103 children (44 females, 59 males) with cranial diabetes insipidus (mean age 6.9 years at diagnosis) treated with intramuscular (59), intranasal (84) and/or oral (64) DDAVP, over a mean follow-up period of 5.2 years. RESULTS: Eight patients died. For at least two children death was related to water intoxication. Major complications (symptomatic water overload with or without seizures) or asymptomatic hyponatraemia were observed in 33 patients. The incidence of total complications was significantly higher in cortisol deficient patients than in those with normal cortisol reserve (36% vs 6%). In patients on concomitant carbamazapine treatment major complications were more frequent in comparison to the remaining patients (33% vs 10%). Although not achieving significance, there were fewer complications using the oral route. CONCLUSIONS: Caution is needed in managing patients with DI, especially if risk factors such as cortisol deficiency or concomitant carbamazepine treatment are present. The oral route of administration seems to be preferred for both convenience and safety. Major changes in dose and formulation should be undertaken in hospital.

Administration, Intranasal↗
PubMedDate not supplied

[Prevalence of Chlamydia pneumoniae in respiratory infections in children: an ambulatory diagnostic problem].

It has been recently suggested that Chlamydia Pneumoniae infection is a common finding among children with acute respiratory diseases. Chlamydia cell culture is difficult and time-consuming to perform. Polymerase chain reaction (PCR) is a more rapid but also more expensive technique used to identify Chlamydia in pharyngeal swab, but it can be performed only in few specialized laboratories. We tested a rapid enzyme immuno-assay to detect Chlamydia in 20 children with respiratory infections (mean age 3.29 years; male:female ratio = 12:8) and in 21 healthy children (mean age 4.70 years male:female ratio = 15:6). Prevalence of Chlamydia isolation from pharyngeal swab was very high in both patients and healthy children without a significative difference in the two considered groups (45% vs 42%, p = 0.8). Specific Chlamydia IgG antibodies were undetectable in all patients and healthy children. Nine out of 20 patients affected by acute respiratory disease were Chlamydia-positive and 11 out 20 were Chlamydia-negative: these two groups didn't differ in regard to clinical and laboratory features, whereas duration of symptoms was significantly longer in Chlamydia-positive patients (9.3 vs 5.5 days, p = 0.014). Our study suggests a high prevalence of Chlamydia pharyngeal swab positivity in both healthy and sick children. Diagnosis of Chlamydia infection was not feasible on the basis of the considered clinical and laboratory findings.

Acute Disease↗
PubMedDate not supplied

[Evaluation of diosmectite in acute diarrhea in children].

The aim of this case-control study, was to estimate clinical effects, safety and parents' assessment of Diosmectite, in acute infantile diarrhoea. Thirty-five children aged 0-5 years, with acute diarrhoea from at least 5 days received alternatively oral rehydration solution (ORS) and Diosmectite (3 g/day for 3 days in children aged under 3 years and 6 g/day for 3 days in children aged over 3 years) (16 cases) or ORS only (19 cases). At discharge, parents' opinion concerning satisfaction for treatment received was evaluated through a questionnaire. Differences in the amount of liquid intake, weigh recovery, resolution of fever, resolution of vomiting and number of loose stools in the first 48 hours of hospitalization were not significant. Diosmectite was well tolerated and no major side effects were found. Parents' satisfaction for therapy resulted higher in the treated group than in the control group, even if differences were not significant. Treatment with ORS and Diosmectite allowed to shorten the mean duration of hospitalization by 0.4 days/children in the treatment group compared to the control group. Further studies with more cases and with higher does of the drug are necessary to confirm our results.

Acute Disease↗
PubMedDate not supplied

Simultaneous determination of DOPAC, MHPG, 5-HIAA and HVA in CSF by direct injection on a liquid chromatograph with coulometric detection.

We describe a direct analysis for simultaneous determination of 3,4-dihydroxyphenylacetic acid (DOPAC), 3-methoxy-4-hydroxyphenylglycol (MHPG), 5-hydroxyindoleacetic acid (5-HIAA), and 4-hydroxy-3-methoxyphenylacetic acid (HVA). After ultrafiltration the samples are applied directly to a high-performance liquid chromatograph with coulometric detection. The appropriate choice of the potentials of the three-coulometric-electrode system eliminates many possible interfering substances. One chromatographic run requires less than 15 min. By this analytical system the lowest amount of DOPAC, MHPG, 5-HIAA and HVA detectable was 0.16, 0.18, 0.90, and 1.48 ng/ml respectively. Coefficient of variation was less than 5% for "within-run" precision and less than 10% for "between-run" precision.

3,4-Dihydroxyphenylacetic Acid↗
PubMedDate not supplied

[Valley/peak ratio and pressure changes during treatment with fosinopril in hypertensive elderly patients].

Antihypertensive drug therapy uniformity of efficacy was evaluated in a group of elderly hypertensive subjects with trough-to-peak ratio, after a period of antihypertensive drug therapy with ACE-inhibitor fosinopril. An ambulatory blood pressure monitoring (ABPM) with evaluation of blood pressure variability assessed by standard deviation (S.D.) and coefficient of variation (C.V.) were evaluated in each subjects. Our preliminary data showed that the treatment with fosinopril had satisfactory uniformity of efficacy during all the 24-hour period, with both full dose (20 mg) and reduced dose (10 mg); little influence on blood pressure variability was determined by antihypertensive treatment.

Aged↗