Biomedical subjects
Publications and source records attributed to M Ferrari.
Adsorption layers of n-dodecanol at the water/air interface show phase transitions at low temperatures [Vollhardt, Fainerman, Emrich, J. Phys. Chem. B 104 (2000) 8536]. Using a drop shape technique it is shown that the dilational elasticity disappears in the coexistence region of the adsorption layer. The relaxation time between the condensed and liquid-like surface states is in the sub-second time range.
A bovine herpesvirus-1 (BHV-1) vaccine expressing glycoprotein D, the form with the transmembrane anchor removed, was evaluated for inducing immunity in calves. The plasmid encoding gD of BHV-1 was injected three times to nine calves, using three animals for each of the following routes: intramuscularly (i.m.), intradermally (i.d.), or intranasally (i.n.). Three additional calves were given the plasmid vector only and served as unvaccinated controls. When calves were subjected to challenge infection with BHV-1, all vaccinated calves as well as the controls developed a typical severe form of infectious bovine rhinotracheitis. However, compared to the controls, the vaccinated calves showed earlier clearance of challenge virus. Moreover, the calves given the vaccine i.m. developed neutralizing antibody to BHV-1 between 21 and 42 days following the first injection of vaccine, whereas in calves vaccinated either i.d. or i.n., as well as the controls, antibody first appeared in their sera 14 days post-challenge infection.
BACKGROUND: The organ shortage mandates that grafts with complex vascular lesions be considered for graft rescue. METHODS: Surgical graft rescue was attempted in 8 patients bearing 8 kidneys and 2 pancreata that showed complex vascular lesions deemed not suitable for interventional radiology procedures. RESULTS: All procedures but 1 were performed under elective conditions. Seven grafts were repaired in situ, while cooling the organ through retrograde venous perfusion, and 3 kidneys were explanted, repaired extracorporeally, and retransplanted. All vascular reconstructions remain patent after a mean follow-up period of 3.3 years (+/-2.1 years). CONCLUSIONS: Careful patient selection, multidisciplinary evaluation, and personalized surgical technique may allow the rescue of kidney and pancreas grafts with complex vascular lesions that, otherwise, would be lost.
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BACKGROUND: Variations in the prevalence of respiratory symptoms according to geo-climatic factors could provide important clues to the knowledge of the aetiology of asthma. METHODS: Geo-climatic variations in the prevalence of current asthma, allergic rhinitis and chronic cough, and phlegm were assessed on a random sample of 18 873 subjects (response rate = 72.7%) from different climatic regions of Italy. An ecological analysis, supported by robust statistical methods, was employed to investigate potential trends. RESULTS: The prevalence of all symptoms was significantly heterogeneous throughout the peninsula. Only asthma-like symptoms showed a north-south trend: the prevalence increased at a decreasing latitude [odds ratio (OR) varies from 0.92 to 0.96, P < 0.05], at a decreasing distance from the sea (OR: 0.90-0.93 for 30 km distance, P < 0.05), at higher annual mean temperatures (OR: 1.11-1.14, P < 0.05) and at smaller annual temperature ranges (OR: 0.94-0.95, P < 0.05). Of the geo-climatic variables considered, temperature range had the greatest influence on most asthma-like symptoms. No association was found between geo-climatic variables and allergic rhinitis or chronic cough and phlegm. CONCLUSIONS: Asthma prevalence seems to be significantly affected by climate as asthma-like symptoms were more common in central-southern Italy, with a Mediterranean climate, than in areas with a continental climate (northern Italy).
We conducted a case-control study to evaluate the relationship between ischemic stroke in young adults (<45 years of age) and plasma homocysteine (Hcy), plasma folate and vitamin B(12), after a methionine load. We studied 42 patients with a history of ischemic stroke and 29 controls with a negative clinical history of cardio- or cerebrovascular diseases, venous thrombosis and renal disease. A fasting blood sample was drawn from each participant; the second and third samples were collected, respectively, 120 and 240 min after the methionine load. Whilst there was no difference between controls and patients in basal total homocysteine (tHcy), we found a statistically significant difference in both the 120- and 240-min samples. We compared the basal and 240-min tHcy in patients and controls. We obtained a median value of 17.8 and 11.6 micromol/l in patients and controls, respectively. The difference between these two values was highly significant. The methionine loading test (MLT) reveals Hcy metabolism abnormalities that were not revealed by the basal sample. MLT may help identify and treat this new risk factor, which seems to be both atherogenic and prothrombotic, and is hypothesized to operate through various mechanisms.
BACKGROUND: Lymphoscintigraphy (LS) and sentinel lymph node biopsy (SLNB) have typically been contraindicated for pregnant patients diagnosed with breast cancer because they are considered unsafe. PATIENTS AND METHODS: Twenty-six premenopausal non-pregnant patients who were candidates for LS underwent peritumoral injection of approximately 12 MBq of 99mTc-HSA nanocolloids. Static [15 min and 16 h post-injection (p.i.)] and whole-body (16 h p.i.) scintigraphic images were acquired. Activity concentration in the urine (0-2, 2-4, 4-8, 8-16 h p.i.) was evaluated by a gamma-counter. Activity in the bloodstream was measured at 4 and 16 h p.i. Thermoluminescent dosimeters (TLD) were placed, before tracer injection, on the injection site, between injection site and epigastrium (two points), and on the epigastrium, umbilicus and hypogastrium, and were removed before surgery. RESULTS: Scintigraphic images showed no radiotracer concentration except in the injection site and in the sentinel node. In all patients, the total activity excreted within the first 16 h was <2% of the injected activity. Activity in the blood pool was, at each time point, <1% of the injected activity. In 23 of 26 patients, all absorbed dose measurements were lower than the sensitivity of the TLD (<10 microGy); in the remaining three patients, the absorbed doses at the level of epigastrium, umbilicus and hypogastrium were in the following ranges: 40-320, 120-250 and 30-140 microGy, respectively. CONCLUSIONS: According to our standard technique (12 MBq of 99mTc-HAS), LS and SLNB can be performed safely during pregnancy, since the very low prenatal doses from this diagnostic procedure, when properly performed, do not significantly increase the risk of prenatal death, malformation or mental impairment.
AIM: To evaluate the ability of two luting procedures for bonding translucent fibre posts to form resin tags, adhesive lateral branches, and resin dentine interdiffusion zones (RDIZ). METHODOLOGY: Forty root filled teeth, extracted for periodontal reasons, were selected for the study. The teeth were randomly divided into four groups of 10 each. Group 1: One Step, light-cured (LC) 20 s + dual link resin cement (LC 20 s); group 2: One Step, not light-cured (NLC) + dual link resin cement (LC 30 s); group 3: One Step (NLC) + dual link resin cement (LC 60 s); group 4: One Step (NLC) + dual link resin cement (LC 90 sec). Forty translucent fibre posts (DT posts, RTD) were inserted. Then, root specimens were processed for scanning electron microscope (SEM) observations to assess the continuity of the RDIZ, the presence or absence of gaps and the density and morphology of resin tags using a four-step scale method. RESULTS: With all luting procedures the formation of a RDIZ occurred. However, the microscopic examination of adhesive interfaces revealed that the percentage of RDIZ was significantly higher in group 1 than in the other three groups (P < 0.05). Group 4 had a higher percentage of RDIZ than group 3, which in turn exhibited a greater percentage than group 2, but these differences were not statistically significant (P > 0.05). Resin tag formation was evident in all the groups. The characteristic reverse cone shape of resin tags was always noted in the coronal and middle third of all groups, and in the apical third of group 1. In the apical third a shorter length and a less uniform appearance of resin tags were noted in groups 2, 3 and 4. CONCLUSIONS: In this laboratory study, when bonding a translucent fibre post into a root canal, the luting procedure including light curing of the adhesive solution before the placement of the cement was more satisfactory, from a SEM standpoint, than the procedure involving the simultaneous curing of adhesive and cement (one step procedure).
OBJECTIVE: To assess the potential for recovery of impaired microvascular function in collateral dependent myocardium after recanalisation of a chronic total coronary occlusion and the determinants of this recovery. PATIENTS AND DESIGN: 120 patients underwent a successful recanalisation of a chronic total coronary occlusion (duration > 2 weeks) and a follow up angiography after a mean (SD) of 5.0 (1.2) months. The coronary flow velocity reserve (CFVR) and the fractional flow reserve were measured after recanalisation and at follow up. Global and regional left ventricular (LV) function were analysed by quantitative angiography. RESULTS: Microvascular dysfunction, defined by a CFVR < 2.0 and a fractional flow reserve > or = 0.75, was observed in 55 (46%) patients after recanalisation. Microvascular function improved during follow up in 24 (20%). The CFVR increased during follow up from 2.01 (0.58) to 2.50 (0.79) (p < 0.001), due to a decrease in basal average peak velocity from 30.7 (14.9) cm/s to 25.5 (13.3) cm/s (p = 0.001). Improved microvascular function was associated with an improved regional LV function, shown by a correlation between increased wall motion severity index and increased CFVR (r = 0.38, p = 0.003). The major determinant of microvascular dysfunction at baseline was the presence of diabetes mellitus (odds ratio 4.3, 95% confidence interval 1.8 to 10.2), which remained so at follow up (odds ratio 4.1, 95% confidence interval 1.3 to 13.4). Improvement of LV function was not impaired by the presence of microvascular dysfunction after recanalisation. CONCLUSIONS: The frequently observed microvascular dysfunction after recanalisation of a chronic total coronary occlusion is a transient phenomenon in most patients and is influenced by the presence of diabetes mellitus. It does not impede the recovery of LV function. Improved regional LV function is associated with improved microvascular function.
OBJECTIVES: To evaluate the feasibility of percutaneous aortic valve replacement without cardiac arrest in animal experiments. METHODS: A self expanding nitinol stent, containing pulmonary valves from pigs in its proximal part, was implanted in six pigs (94-118 kg) by means of a 25 French catheter through the left subclavian artery under guidance of fluoroscopy and transoesophageal echocardiography. During stent deployment the original aortic valve was pushed against the aortic wall by the self expanding force of the stent while the new valve was expanded. RESULTS: It was possible to replace the aortic valve in the beating heart in four pigs (67%) with no complication or relevant drop in blood pressure. The procedure failed in two pigs (33%) due to dysfunction of the catheter device in one case and to problems with correct positioning in the left ventricular outflow tract in the other. After successful stent valve implantation, dopamine was infused in doses of 5 microg/kg/min, 10 microg/kg/min, and 15 microg/kg/min. Cardiac output increased from 4.4 to 8.8 l/min and the mean arterial pressure rose from 79 to 105 mm Hg. The maximum peak to peak pressure gradient across the valve carrying stent reached a maximum of 8 mm Hg under dopamine infusion. All pigs were killed six hours after transvascular aortic valve replacement. The chest was opened, and the left ventricle and the ascending aorta were carefully inspected. There were no signs of malfunction of the implant, of damage of the aortic vessel wall, or of obstruction of the coronary ostia. CONCLUSIONS: Percutaneous aortic valve replacement with a self expanding nitinol stent in the beating heart is possible. The device was safe under pharmacological stress test. After successful chronic animal experiments, this concept may become a feasible option for treating patients with relevant aortic valve disease but where open heart surgery would be risky.
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Endodontically treated teeth restored with posts are susceptible to coronal leakage after long-term function. We hypothesize that demineralized collagen matrices (DCMs) created in dentin by acidic zinc phosphate cement within the dowel spaces degrade with time. Forty-two post-restored teeth were extracted after three periods of clinical service and were examined, by means of scanning and transmission electron microscopy, for the status of the DCMs. SEM revealed a progressive degradation of the DCMs, becoming less dense after 3 to 5 years, losing structural integrity after 6 to 9 years, and partially disappearing after 10 to 12 years. TEM revealed evidence of collagenolytic activity within the DCMs, with loss of cross-banding and unraveling into microfibrils, and gelatinolytic activity that resulted in disintegration of the microfibrils. Bacterial colonization and the release of bacterial enzymes and of host-derived matrix metalloproteinases may contribute to the degradation of collagen fibrils in root dentin after clinical function.
Adhesive dentistry should effectively restore the peripheral seal of dentin after enamel removal. We hypothesize that non-rinsing, simplified, one-step self-etch adhesives are effective for minimizing dentin permeability after tooth preparation procedures. Crown preparations in vital human teeth were sealed with Adper Prompt, Xeno III, iBond, or One-Up Bond F. Epoxy resin replicas were produced from polyvinyl siloxane impressions for SEM examination. Dentin surfaces from extracted human teeth were bonded with these adhesives and connected to a fluid-transport model for permeability measurements and TEM examination. Dentinal fluid droplets were observed from adhesive surfaces in resin replicas of in vivo specimens. In vitro fluid conductance of dentin bonded with one-step self-etch adhesives was either similar to or greater than that of smear-layer-covered dentin. TEM revealed water trees within the adhesives that facilitate water movement across the polymerized, highly permeable adhesives. Both in vitro and in vivo results did not support the proposed hypothesis.
Fetal DNA in maternal plasma may represent a source of genetic material for prenatal noninvasive diagnosis of genetic diseases. We evaluated a cohort of physiological pregnancies to determine if fetal DNA can be retrieved at any gestational week in sufficient quantity to be analyzed with advanced mutation detection technologies. We performed fetal DNA quantification by real-time polymerase chain reaction (PCR) on the SRY gene in 356 women sampled from 6 to 40 gestational weeks. Fetal DNA was retrieved at any week. All female fetuses were correctly identified. In 5 of 188 (2.6%) male-bearing pregnancies, no amplification was obtained. For noninvasive testing, complete clearance of fetal DNA after delivery is mandatory. Long-term persistence was not detected in women with previous sons or abortions. These findings confirm that maternal plasma may represent the optimal source of fetal genetic material. For noninvasive diagnosis of genetic diseases, we evaluated microchip technology. The detection limit for a minority allele determined by diluting a mutated DNA into a wild-type plasma sample was 5 genome equivalents, indicating that the test might be applied to the identification of paternally inherited fetal alleles in maternal plasma. The addition of peptide nucleic acids (PNAs) to either the PCR reaction or the chip hybridization mixture allowed approximately 50% inhibition of wild-type allele signals.
In a limited study, comprising only ten patients, we have previously reported that allogeneic irradiated RCC-cell-line cells, engineered to produce IL-2 (ACHN-IL-2), admixed with autologous metastatic formalin-treated tumour cells were used to vaccinate MRCC patients in progression of disease and also receiving IL-2 immunotherapy. The cells, admixed to autologous TC, were administered subcutaneously. We now report an extended study on thirty patients and one hundred thirty-one controls. Patients received 4-20 injections (mean 10 +/- 4), containing an average of 92 x 10(6) +/- 45 x 10(6) ACHN-IL-2 transfected cells (a minimum of 25 x 10(6), and a maximum of 200 x 10(6)). Autologous TC, admixed to allogeneic, were also administered by 4-16 s.c. injections (mean 7 +/- 3), i.e. a total of 12 x 10(6)-160 x 10(6) cells. Vaccination was administered during 73-1451 (307 +/- 316) days, and the follow-up continued for 1122 +/- 1240 days (106-5137). Throughout this period, the patients continued receiving the previously set immunotherapy treatment. No adverse side effects related to the treatment were noticed. One complete and four partial tumour responses were observed, as well as nine cases of stable disease. Thirteen patients died in the treated group (43%) and 63 (44%) in the control group. Responding patients resumed progression in 4-11 months and died 18 and 36 months after beginning the vaccine therapy. The Gehan Wilcoxon's test showed a significantly (P < 0.01) better survival in the vaccinated patients compared to that of the controls. Thus, we confirm, in an increased number of patients and an extensive follow-up, that our vaccination protocol is safe, devoid of adverse side effects, and promising.
The authors carried out genetic analyses and visual electrophysiologic evaluations in six asymptomatic sons and daughters of patients with symptomatic cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL). Three subjects showed Notch3 Cys146Tyr missense mutation and a dysfunction of the outer, middle, and innermost retinal layers, with normal neural conduction in postretinal visual pathways, whereas in the remaining subjects without genetic mutations, no electrophysiologic abnormalities were found. An early vascular retinal impairment in CADASIL may precede the onset of clinical manifestations.
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