Search PubMed⌕ Search

Biomedical subjects

R Urso

Publications and source records attributed to R Urso.

At least 19 recordsLinked to original sources
PubMed2006

Classical and molecular analyses to characterize commercial dry yeasts used in wine fermentations.

AIMS: The aim of the work was to apply PCR-temperature gradient gel electrophoresis (PCR-TGGE) and restriction enzyme analysis (RE) assays to identify commercially available starters of Saccharomyces cerevisiae sensu stricto complex. METHODS AND RESULTS: To characterize an analysed pool of 62 active dry yeasts of different brands used in wine fermentation practices, classical microbiological tests were also performed as well as evaluation of contamination with lactic acid bacteria and non-Saccharomyces yeasts. PCR-TGGE and RE were used in order to provide fast and reliable methods to identify and differentiate enological yeasts. Proposed molecular methods enabled to identify particular strains within 36 h after colony isolation and directly from dry yeast suspension. CONCLUSIONS: The methods are highly recommended to obtain reliable results on yeast strain differentiation in a significantly shorter time if compared to classical fermentation tests. SIGNIFICANCE AND IMPACT OF THE STUDY: The obtaining of yeast strain differentiation in a short time and without plating is a good tool for a rapid discrimination among enological strains used as starters in enological practices.

Colony Count, Microbial↗
PubMed2005

Is a long-term ranitidine-based triple therapy against Helicobacter pylori only a heritage of the past? A prospective, randomized clinicopharmacological study.

BACKGROUND: Acid suppression plus two antibiotics is currently considered the gold standard anti-Helicobacter pylori treatment, but the effective role of gastric antisecretory drugs is still poorly understood. AIMS: To compare a 14-day ranitidine-based triple regimen against Helicobacter pylori with one based on omeprazole, and to study the influence of antisecretory drugs on metronidazole pharmacokinetics in human plasma. METHODS: A total of 150 dyspeptic H. pylori-infected patients were randomized for ranitidine 300 mg b.d. (RCM group) or omeprazole 20 mg b.d. (OCM group) 14-day triple therapy, with clarithromycin 500 mg b.d. and metronidazole 500 mg b.d. On the eighth day of therapy, metronidazole pharmacokinetics was studied in plasma by high-performance liquid chromatography. The pharmacokinetic parameters (terminal half-life, area under the curve, peak-plasma level, peak time) of metronidazole were computed using standard non-compartmental methods. H. pylori status was monitored before and 4 weeks after the end of therapy by histology, serology and rapid urease test. RESULTS: On an intention-to-treat basis, eradication rates were 91 and 76% for the RCM and OCM groups respectively (P < 0.02). Significantly different pharmacokinetic parameters of metronidazole were found between the groups: peak-plasma level (P < 0.01) and area under the curve (P < 0.02). CONCLUSION: Our results show that the RCM regimen was more effective than that based on OCM and that the antisecretory drugs affected metronidazole availability, increasing the efficacy of ranitidine-based regimens.

Adolescent↗
PubMed2005

Pharmacokinetics of mitomycin C after resection of peritoneal carcinomatosis and intraperitoneal chemohyperthermic perfusion.

Over the last few years surgery on patients with abdominal malignancies has become more aggressive but the majority of patients present locoregional recurrence as peritoneal dissemination. Cytoreductive surgery followed by intraperitoneal chemohyperthermic perfusion (ICHP) has been described for treatment and prevention of locoregional cancer spread from various origins. This paper reports our study of the pharmacokinetics of mitomycin C (MMC) administered by intraperitoneal chemohyperthermic perfusion (ICHP) in patients with peritoneal carcinomatosis. 28 patients received MMC 20 mg/m2 intraperitoneally as a perfusion over 60 min. MMC was determined in perfusate, plasma and urine samples with a UV-HPLC method. A compartmental model was used to fit the drug concentrations in plasma and perfusate. Our results showed a mean maximum plasma concentration (Cmax) of 0.14 +/- 0.086 microg/ml with a peak time (Tmax) of 48..7 +/- 5.61 min. The mean area under the curve (AUC) and terminal half-life (t1/2) were 15.8 +/- 9.8 mg x min/L and 83.7 +/- 31.74 min respectively. Clearance (CL) was estimated by fitting the data by a compartmental model and the mean value was 72 +/- 66 L/h. The percent of the dose absorbed was very variable and ranged between 14 and 57% (mean 37 +/- 14%). The mean percentage of dose recovered unchanged in the urine during 24 hours was 7.21 +/- 3.73%. We conclude that ICHP in patients with peritoneal surface malignancies seems to have clinical value since it gives high peritoneal and tumor MMC concentrations with limited systemic exposure and toxicity.

Adult↗
PubMed2004

[Guidelines for the management of HCV infection in HIV-infected patients. Istituto Nazionale per le Malattie Infettive Lazzaro Spallanzani].

It is crucial to ensure an optimal clinical management of HCV infection in HIV-co-infected persons. The reasons for the development of guidelines on HCV-infection treatment in HIV-infected persons arise from the need for a standardised management of HIV/HCV coinfection in our Institute. The aim of these guidelines are: to clarify principles of clinical management of HCV infection in HIV-infected patients to care-providers; to improve the awareness of HIV-infected patients cared for our Institute on current management of HCV infection; to improve the quality of care on this topic. These guidelines, based on Evidence based Medicine principles, have been developed by a panel of experts, who conducted a systematic review of the literature, mainly taking into account current international recommendations. In the present document, the most frequent clinical presentation occurring in the management of HIV/HCV co-infected patients at our Institution are discussed. The adherence to present guidelines and their effectiveness at our Institution, outcome indicators will be evaluated. The present guidelines cannot entirely substitute the judgement of an expert clinician. However, adherence to these guidelines will contribute to the improvement of the standard of care of HIV/HCV-co-infected persons.

Anti-HIV Agents↗
PubMed2000

gammadelta T-cell anergy in human immunodeficiency virus-infected persons with opportunistic infections and recovery after highly active antiretroviral therapy.

gammadelta T lymphocytes recognize non-peptidic microbial antigens without antigen processing and major histocompatibility complex (MHC) restriction, representing an early defence mechanism against invading pathogens. As a defective response to non-peptidic antigens was observed in human immunodeficiency virus-positive (HIV+) persons, the aims of this study were twofold: to analyse the incidence of gammadelta T-cell anergy in HIV+ positive patients with opportunistic infections/co-infections (HIV-OIC), and to investigate the role of highly active antiretroviral therapy (HAART) on gammadelta T-cell functions. Peripheral gammadelta T-cell distribution and in vitro reactivity to a non-peptidic mycobacterial antigen, isopentenyl pyrophosphate (IPP), were analysed. gammadelta T-cell subset distribution was altered more in HIV-OIC patients than in asymptomatic HIV+ subjects (HIV-ASY). Specifically, the Vdelta2/Vdelta1 ratio was inverted as a consequence of a decrease in Vdelta2 T-cell number. Moreover, IPP-stimulated Vdelta2 T cells from the HIV-OIC group displayed a major defect in interferon-gamma (IFN-gamma) production. Interestingly, HAART induced a sustained recovery of naive CD45RA+ and CD62L+ T cells and restored gammadelta T-cell function. Accordingly, in vitro CD45RA depletion resulted in gammadelta T-cell hyporesponsiveness. Altogether, the incidence of gammadelta T-cell anergy was increased in HIV-OIC patients and dependent on CD45RA helper function. Moreover, HAART was able to restore gammadelta T-cell reactivity, extending the immune recovery to non-peptide microbial antigens.

AIDS-Related Opportunistic Infections↗
PubMed2000

[Dysmetabolic syndrome related to HIV-1 protease inhibitors. Review of the literature and personal data].

HIV-positive patients receiving antiretroviral therapy with HIV-1 protease-inhibitors (PI) frequently show insulin-resistance, impaired glucose tolerance, hypertriglyceridaemia and lipodystrophy (LD). LD has often been reported only after the beginning of PI therapy. Some authors link LD to HIV chronic infection, some others suggest that PIs increase pre-existent disturb. Preliminary data of an observational study drawn in IV day-hospital of Spallanzani Institute in Rome showed hypertriglyceridaemia in 36.4% and hyperglycaemia in 11.2% of patients treated with PI. Carr suggests that such drugs should have this lipid-increasing effect because of their inhibition of low density lipoprotein-receptor-related protein, cytoplasmic retinoic-acid binding protein type 1 and P450 3A cytochrome. This theory doesn't explain why both untreated patients and treated with only reverse transcriptase inhibitors show sometimes the same disorders. According to another hypothesis Tumor necrosis factor-alpha, through inhibition of lipoprotein-lipase, would determine high fat-storage in the adipose tissue. Cardiovascular risk factors have always to be assessed before starting a therapy with PI. Glycaemia, triglyceridaemia, cholesterolaemia have to be performed every three months during the treatment and, if necessary, C-Peptide and insulinaemia too. A treatment with lipid-lowering drugs is always recommended in patients with hypertriglyceridaemia > 500 mg/dl and/or hypercholesterolaemia LDL > 190 mg/dl in two following checks. Fibrates have proven to be effective in reducing hypertriglyceridaemia, but there is no certainty that such therapies could have good effects on the LD itself too.

Diabetes Complications↗
PubMed2000

[The correlations between color Doppler using a contrast medium and the neoangiogenesis of small prostatic carcinomas].

PURPOSE: To investigate if the use of a contrast agent (Levovist) improves the specificity of US in the diagnosis of prostate carcinoma, having the results of prostate biopsy as the gold standard. MATERIAL AND METHODS: Thirty patients with physical findings suspicious for prostate carcinoma and PSA ranging 5 ng/mL to 15 ng/mL were examined with transrectal US (TRUS) integrated with the color Doppler mode and contrast agent administration (4 g injected at 4 mL/min: 300 mL concentration). RESULTS: Based on bioptic and surgical results, 14 prostate carcinomas were found, all of them < 1.2 cm. Conventional US recognized the suspected nodule in 11 cases, with 78% sensitivity and 93% specificity. Color Doppler showed color signals in 8/14 cases, which were peripheral to the lesion or intranodular, but did not add any important finding to those of gray-scale US. In contrast, contrast enhanced studies showed 13/14 carcinomas, which improved sensitivity significantly (92%). Particularly, 11/14 lesions had a typical avascular pattern within the strongly enhanced peripheral gland, while 2 small lesions only exhibited intranodular vessels. DISCUSSION AND CONCLUSIONS: We compared our results with the Microscopic Angiogenesis Grading System (MAGS) index and found it exceeded 30 in the 11 avascular lesions value indicates microneoangiogenesis. In the other two cases a value < 30 was correlated with a different type of tumor vascularization typical of macroangiogenesis.

Aged↗
PubMed1998

Pharmacokinetic and immunogenic behavior of three recombinant human GM-CSF-EPO hybrid proteins in cynomolgus monkeys.

MEN 11,300, MEN 11,301, and MEN 11,303 are three recombinant human hybrid proteins that, as has recently been described, induce in vitro erythroid differentiation. This article provides data on their pharmacokinetic and immunogenic behavior after repeated i.v. administration to cynomolgus monkeys at 0.8 or 1.6 micrograms/kg doses. Pharmacokinetic data, obtained after the first administration, showed that the half-life (t1/2) and clearance (CL) values are dose dependent, with no significant differences among the three hybrid proteins. After the tenth administration, MEN 11,300 and MEN 11,301, both a high and low dose, and MEN 11,303 at high dose were undetectable in plasma, whereas MEN 11,303 at the lower dose showed no alteration in its pharmacokinetic profile. Immunologic analyses of plasma provided an explanation for this different pharmacokinetic behavior. In fact, plasma samples from animals treated repeatedly with MEN 11,300 and MEN 11,301 showed specific antibody formation in response to both the high- and the low-dose regimens. These antibodies exerted in vitro a strong neutralizing activity of the hybrid proteins, with a predominant specificity for the erythropoietin (EPO) portion. By contrast, MEN 11,303 at the lower dose did not induce a detectable antibody response whereas the antibodies observed on the high-dose regimen did not exert neutralizing activity against the hybrid proteins nor against granulocyte-macrophage colony-stimulating factor (GM-CSF) or EPO. Hematologic parameters were not affected by the treatments, thus indicating that the anti-EPO neutralizing antibody response does not cross react with the endogenous monkey cytokine. The overall immunogenicity data suggest that among the three fusion proteins, MEN 11,303 could have a lower immunogenic potential.

Animals↗
PubMed1998

Artificial skin equivalent differentiation depends on fibroblast donor site: use of eyelid fibroblasts.

Our objective was to construct and explore human skin equivalents from several normal and pathologic donor skin sites to determine if the fibroblast origin influences epidermal differentiation. Also, we wanted to find out if fibroblasts from some donor sites produced epidermis of superior quality for plastic surgery repairs. Skin equivalents were constructed from 15 normal skin specimens, 9 normal eyelid specimens, 15 lesional skin specimens taken from patients with psoriasis, and 4 specimens from keloid scars. Results show that the tissue origin of the donor fibroblasts determines epidermal differentiation and the time period for regeneration. Eyelid fibroblasts were very dependable in establishing well-differentiated skin equivalents in all nine specimens. Our findings contribute to the accumulated knowledge of wound healing and should also be of value in skin grafting, especially when large areas are denuded as in burns, severe trauma, or cancer ablation.

Adolescent↗
PubMed1998

[Insulin resistance. Receptor and post-receptor abnormalities].

Insulin action starts with binding to a membrane receptor (insulin receptor-tyrosine kinase) and with activating an insulin receptor substrate 1 (IRS-1) and substrate 2 (IRS-2). Insulin receptors interact at least with three cascade reactions, phosphorylating G proteins and IRS-1, that activate PLC "ras" and PI-3-K. NIDDM can be defined as a disease caused by defective transduction of insulin signals and IR as a complex phenotype manifesting itself, emphasized by individual and environmental factors, in the cellular systems of signal transduction. IRS is a syndrome characterized by NIDDM, hypertension, visceral obesity, CHD: the X syndrome. Up to day the described mutations of the insulin-receptor gene are rare (e.g. the leprechaunism): genetic IR. Obesity is the principal cause of IR by receptorial and post-receptorial defects: metabolic IR. The obese skeletal muscle shows a reduction of insulin receptor and IRS-1 phosphorylation and of PI-3-K activation; the scarce expression of these proteins would determine the muscular IR. IR is a pattern of essential hypertension. Hypertension, dyslipidemia and abnormality of glucose metabolism are linked by IR. The so called high erythrocyte Na(+)-Li+ counter-transport is a new biochemical marker for IR and hypertension. These drugs can reduce IR: metformin, sulphonilureas, fibrats, dexfenfluramine, troglitazone, doxazosin, ACE-inhibitors.

Diabetes Mellitus, Type 2↗
PubMed1998

A new model to assess tcpO2 changes during heat-dependent vasodilation: preliminary observations.

The transcutaneous pO2 (tcpO2) changes induced by the increase of temperature to 45 degrees C after electrode stabilization at 37 degrees C were continuously recorded. The mathematical analysis of the curve led us to identify three different parameters: the half-slope "b" time, the angular "mT" coefficient and the angular "mb" parameter, which are not simply the expression of the maximum vasodilation capacity but mainly of the dynamic response of the microcirculatory system to skin heating. These parameters derived from the computerized mathematical analysis of the curve can be also obtained by a graphical approach with a very good approximation. The angular "mb" coefficient was shown to possess the highest statistical power in discriminating the POAD patients from normal controls. The clinical relevance and the possible pathophysiological meaning of these preliminary observations have to be confirmed.

Ankle↗
PubMed1997

Pharmacokinetics of isosorbide dinitrate in healthy volunteers after 24-hour intravenous infusion.

No studies have examined the pharmacokinetics of isosorbide dinitrate (ISDN) after infusion of long duration, even though such infusions are used in patients. We therefore measured ISDN and its active metabolites, isosorbide-5-mononitrate (IS5MN) and isosorbide-2-mononitrate (IS2MN), in plasma of 9 healthy volunteers who received a continuous intravenous infusion of ISDN for 24 hours at a dose rate that lowered diastolic blood pressure by 10% during the first 30 minutes of infusion. All subjects tolerated the infusion except one who experienced intolerable headache. Five subjects received 1 microgram.min-1.kg-1, one 2 micrograms.min-1.kg-1, and two 4 micrograms.min-1.kg-1 ISDN, whereas the full rate of 6 micrograms.min-1.kg-1 was used continuously in one subject. At all infusion rates the plasma concentrations of ISDN were higher at 24 hours than at earlier times, suggesting that a steady-state condition had not been reached at that time. The same was true for the mononitrate metabolites, which reached higher plasma concentrations and were cleared more slowly than the parent compound after the end of the infusion. Apparent elimination half-lives of ISDN, IS2MN, and IS5MN were 67 +/- 10 minutes, 115 +/- 13 minutes, and 272 +/- 38 minutes, respectively. Comparison of low-rate infusions (1 and 2 micrograms.min-1.kg-1) with high-rate infusions (4 and 6 micrograms.min-1.kg-1) showed that the plasma concentration ratios at 24 hours of mononitrate metabolites to parent drug and apparent plasma clearance of ISDN were almost halved at the higher infusion rates.

Adult↗
PubMed1997

Endoscopic approach to traumatic visual loss.

OBJECTIVE: To review our experience with the use of endoscopic optic nerve decompression in traumatic blindness. METHOD: We did a retrospective analysis of patients with traumatic blindness that underwent endoscopic decompression of the optic canal to determine postoperative visual acuity and correlate it to preoperative visual loss and intraoperative findings. The setting was a Level I university trauma center. We identified 8 patients treated with both surgery and steroids over a 10-month period beginning in 1993 (Seven males, one female). RESULTS: Four of six patients with total blindness (no light perception) had improvements in visual acuity. In three patients, visual acuity returned to preinjury levels. One patients with total blindness was operated on 6 weeks after injury and had a visual acuity of 20/800 at 1-year follow-up. Two patients with hand motion preoperatively had improvement in visual acuity. In one patient, vision returned to normal (20/20), and in the other it improved to 20/200). Five patients were operated on after megadose steroid treatment for at least 48 hours failed; four of five noted dramatic improvements in visual acuity. CONCLUSION: The endoscopic approach may be used to successfully decompress the optic nerve in traumatic blindness.

Adolescent↗
PubMed1994

[The pharmacokinetics of antibiotics: parenteral and oral administration, distribution in the organism, elimination].

The efficacy of antimicrobial therapy is largely dependent on the pharmacokinetics of the drug. Pharmacokinetics is the study of the kinetics, that is of the movements of drugs in the body fluids and tissue cells. Often, despite the complexity of mammalian organism, relatively simple compartmental systems are capable to describe the kinetics of many drugs and to provide a rationale in interpreting the experimental results. As most bacterial infections are localized in tissues, the pharmacokinetic modelling of antimicrobial agents should mainly be devoted to clarify the relationship between plasma and tissue drug levels, the former being easily accessible to sampling and the latter more closely related to therapeutic efficacy. In this paper an introduction to pharmacokinetic modelling is presented and the pharmacokinetics of many antimicrobial drugs is discussed.

Animals↗
PubMed1993

Pharmacokinetics of exogenous adenosine in man after infusion.

The plasma kinetics of adenosine was investigated in healthy volunteers after a 1 minute infusion of 2.5, 5 and 10 mg (38.79 and 148 micrograms.kg-1 respectively) and after infusion of 200 micrograms.kg-1 in 10 min followed by 400 micrograms.kg-1 in 10 min. As the dose in the 1 min infusion study was increased the mean CL of adenosine decreased (10.7, 4.70 and 4.14 l.min-1, respectively), its mean half-life increased (0.91, 1.24 and 1.86 min, respectively), and the mean volume of distribution did not show any clear trend (8-13 l). After the 20 minute infusion the plasma level of adenosine reached a peak value comparable to that observed after infusion of 5 mg in 1 min (about 0.5 micrograms.ml-1), but the mean clearance and half-life were significantly different (12.1 l.min-1 and 0.63 min respectively). In all the subjects the plasma concentration of adenosine had returned to the baseline value in 5-15 min after the end of the infusion.

Adenosine↗