PubMed Health⌕ Search

Biomedical subjects

F Raimondi

Publications and source records attributed to F Raimondi.

At least 19 recordsLinked to original sources

Iloprost treatment in patients with Raynaud's phenomenon secondary to systemic sclerosis and the quality of life: a new therapeutic protocol.

OBJECTIVES: To evaluate the clinical efficacy and the effects on the quality of life of iloprost, a prostacyclin analogue, used according to a new protocol in patients with Raynaud's phenomenon secondary to systemic sclerosis. METHODS: In this randomized study, we treated 30 patients with iloprost, given by intravenous infusion, at progressively increasing doses (from 0.5 to 2 ng/kg/min) over a period of 6 h each day for 10 days in two consecutive weeks, with repeated cycles at regular intervals of 3 months for 18 months. The results were compared with those obtained in 30 other patients who received the same drug but with different dosing schemes. RESULTS: The total average daily duration of the attacks, the average duration of a single attack and the average daily frequency of the attacks were reduced significantly in all treatment groups, but the comparison between the groups demonstrated significant differences between patients treated with the new protocol and the others at later times (12 and 18 months). The effects on the quality of life in the group treated with the new protocol, evaluated with the Short Form-36, demonstrated a marked improvement regarding both the scale relating to the physical aspect of the illness and, especially, the scale relating to the mental aspect. CONCLUSIONS: In patients with systemic sclerosis, cyclic intravenous iloprost infusion is efficacious in the treatment of Raynaud's phenomenon. The protocol that we used, compared with others, not only has favourable clinical effects but also leads to a marked improvement in the quality of life.

Adult↗

Changes of arterial hemodynamics in patients with type 2 diabetes mellitus or impaired glucose tolerance.

AIM: The aim of our study was to evaluate the arterial hemodynamics in patients with type 2 diabetes mellitus or impaired glucose tolerance without clinical or Doppler evidence of peripheral arterial disease, in order to early detect vascular damage. METHODS: We studied 20 subjects (12 men and 8 women, aged between 48 and 62 years) with type 2 diabetes mellitus (Group 1), 20 subjects (11 men and 9 women, aged between 49 and 61 years) with reduced glucose tolerance (Group 2), and 20 normal subjects (10 men and 10 women, aged between 48 and 62 years) (Group 3). Each subject underwent strain-gauge plethysmography and the following parameters were evaluated: rest flow (RF); peak flow (PF); PF/RF ratio; time to peak flow (tPF); half-time (t 1/2) and total time (tT) of hyperemic response; basal vascular resistances (BVR) and minimal vascular resistances (MVR). RESULTS: There was no difference among groups in RF, but maximal postischemic flow was reduced in patients with diabetes and with impaired glucose tolerance. The MVR showed a similar behavior, while the basal ones were increased only in the diabetic group. Finally, the t1/2 and the tT of the hyperemic response, that reflect arteriolar reactivity, were significantly reduced, if compared with controls. No significant differences between Group 1 and 2 were found. CONCLUSIONS: These results confirm the presence of hemodynamic modifications in the vascular bed of both diabetics and patients with impaired glucose tolerance, as compared with normal subjects.

Analysis of Variance↗

The psychotic spectrum: validity and reliability of the Structured Clinical Interview for the Psychotic Spectrum.

This study evaluates the validity and the reliability of a new instrument developed to assess the psychotic spectrum: the Structured Clinical Interview for the Psychotic Spectrum (SCI-PSY). The instrument is based on a spectrum model that emphasizes soft signs, low-grade symptoms, subthreshold syndromes, as well as temperamental and personality traits comprising the clinical and subsyndromal psychotic manifestations. The items of the interview include, in addition to a subset of the DSM-IV criteria for psychotic syndromes, a number of features derived from clinical experience and from a review of the phenomenological descriptions of psychoses. Study participants were enrolled at 11 Italian Departments of Psychiatry located at 9 sites and included 77 consecutive patients with schizophrenia or schizoaffective disorder, 66 with borderline personality disorder, 59 with psychotic mood disorders, 98 with non-psychotic mood disorders and 57 with panic disorder. A comparison group of 102 unselected controls was enrolled at the same sites. The SCI-PSY significantly discriminated subjects with any psychiatric diagnosis from controls and subjects with from those without psychotic disorders. The hypothesized structure of the instrument was confirmed empirically.

Adolescent↗

Absorption of fumonisin B1 and aminopentol on an in vitro model of intestinal epithelium; the role of P-glycoprotein.

The aim of the present paper is to evaluate the absorption of fumonisin B1 and its principal metabolite, aminopentol on a human intestinal model, Caco-2 cells, cultured on semi-permeable inserts, that reproduces the two different intestinal compartments: luminal (apical) and serosal (basolateral) side. Following separate exposure in apical and in basolateral compartments, aminopentol passage through the cell layer (in particular from basolateral to apical direction) was shown, while it was not observed for the parent compound. The different aminopentol distribution between the two compartments of the culture system, and its variation in presence of verapamil or probenecid (P-gp and MRP inhibitors respectively), strongly suggests the involvement of P-glycoprotein in the influx/efflux mechanisms of aminopentol in the intestinal cells, reducing its oral bioavailability.

ATP Binding Cassette Transporter, Subfamily B, Mem↗

Prevention of nosocomial infection in the ICU setting.

The aim of this review is to focus the epidemiology and preventing measures of nosocomial infections that affect the critically ill patients. Most of them (over 80%) are related to the device utilization needed for patient life support but responsible for such complications as ventilator-associated pneumonia (VAP), catheter-related bloodstream infections (CRBSI), surgical site infections (SSI) and urinary tract infections (UTI). General recommendations include staff education and use of a surveillance program with a restrictive antibiotic policy. Adequate time must be allowed for hand washing and barrier precautions must always be used during device manipulation. The routine changing of central catheters is not necessary and increases costs; it is necessary to decrease the handling of administration sets, to use a more careful insertion technique and less frequent set replacement. Specific measures for VAP prevention are: 1). use of multi-use, closed-system suction catheters; 2). no routine change of the breathing circuit; 3). lubrication of the the endotracheal tube cuff with a water-soluble gel; 4). maintenance of patient in semi-recumbent position to improve chest physiotherapy. Specific measures for UTI prevention include: 1). use of a catheter-valve instead of a standard drainage system; 2). use of a silver-alloy, hydro gel-coated latex urinary catheter instead of uncoated catheters. By implementing effective preventive measures and maintaining strict surveillance of ICU infections, we hope to affect the associated morbidity, mortality, and cost that our patients and society bare. More clinical trials are needed to verify the efficacy of prevention measures of ICU infections.

Catheterization↗

"Safe" hyperbilirubinemia is associated with altered neonatal behavior.

Treatment of neonatal jaundice is currently recommended for higher bilirubinemia levels than before. Using the Brazelton Neonatal Behavior Assessment Scale, we found that a series of 28 healthy, untreated, term neonates with moderate bilirubinemia scored significantly less than an equal number of appropriately matched controls with low bilirubinemia for visual and auditory items, both inanimate and animate. Also, a greater lability of state, a lower self-quieting ability and more frequent tremors were found in the jaundiced group. We conclude that hyperbilirubinemia per se, even in the concentration range where phototherapy is not currently recommended, can give rise to alterations in neonatal behavior.

Acoustic Stimulation↗

[Infection control and prevention in intensive care: environmental aspects].

Surveillance is understood as the monitoring over time of the onset of preventable infection and/or microbial colonization in patients in intensive care units (ICU), where the prevalence of nosocomial infections, particularly those caused by microorganisms multiresistant to antibiotics, is alarmingly high. Surveillance deals with: 1) pathogens responsible for infection and their patterns of antibiotic resistance; 2) epidemics; 3) endemic infections selected according to predictability; 4) frequency of use of specific invasive procedures, where the greater the use, the higher the frequency of nosocomial infections associated with them; 5) use of antibiotics. Surveillance is operated through: 1) the microbiology laboratory, which is responsible for accurate surveillance of hospital infections; 2) the active surveillance on the wards, which concerns: a) identification of infections either on admission or during hospitalization or both, b) use of invasive procedures, control of parameters, and data collection, c) type of patients treated, identification of infected patients and data analysis and interpretation. Infection prevention complementary to surveillance starts with the adoption of strategies and interventions based on the application of universal precautions and/or on the route of transmission. A crucial point is the sterilization and disinfection of medical devices. In recent years there has been a steady rise in the number of infections caused by medical devices, most likely because of the increasing use of sophisticated and complex equipment that is often difficult to decontaminate and because of the rise in the number of immunocompromised patients or those susceptible to infections.

Critical Care↗

Enteropathogenic Escherichia coli strain RDEC-1 produces a novel electrogenic factor active on rabbit ileum in vitro.

BACKGROUND: Attaching and effacing Escherichia coli demonstrate marked species specificity in inducing diarrhea, although its mechanism remains largely unclear. The purpose of this study was to investigate the existence of a soluble, species-specific factor that induces diarrhea in an in vitro model. METHODS: Stripped rabbit ileum was mounted in Ussing chambers, and changes in potential difference and short-circuit current were monitored after the addition of bacterial culture supernatant. RESULTS: The culture supernatant from rabbit-specific strain RDEC-1, but not from human-specific enteropathogenic Escherichia coli strain E2348/69, induced an increase in potential difference and short-circuit current in rabbit ileum mounted in Ussing chambers. This electrical signal was related to chloride ion secretion, was absent in colonic tissue, and was retained in the 30 to 100-KDa fraction of the supernatant. Preliminary experiments failed to show an involvement of calcium or cyclic nucleotides as intracellular messengers. RDEC-1 cured of a 42-MDa plasmid lost the enterotoxicity whereas conjugation of the plasmid into the negative E. coli recipient HB101 resulted in the expression of toxicity. CONCLUSIONS: The authors describe a novel, species-specific factor that helps to explain RDEC-1 diarrhea, which may be relevant to the pathogenesis of enteropathogenic Escherichia coli infection.

Animals↗

FAS engagement drives apoptosis of enterocytes of coeliac patients.

BACKGROUND: Villus atrophy is the most distinctive sign of untreated coeliac disease (CD) and epithelial apoptosis is considered to be involved in this stage of the coeliac lesion. The extent of villus atrophy is, however, not homogeneous and patients with patchy or mild lesions have been described. AIMS: To address: (a) the degree of "patchiness" in untreated CD patients; and (b) to clarify if apoptosis, and eventually which trigger drives it, causes epithelial damage. PATIENTS: Twenty of 40 untreated, 14 treated coeliac patients, and 15 controls received five or more multiple duodenal biopsies; the remaining 20 untreated CD patients had no more than three biopsies. METHODS: All biopsies were analysed to monitor the presence of a "flat" mucosa. Biopsies of 14 untreated, 10 treated coeliacs, and seven controls were cultured with or without gliadin. DNA fragmentation was studied by terminal deoxynucleotidyl transferase (TdT) mediated dUTP digoxigenin nick end labelling (TUNEL), and FAS and Ki67 expression by immunohistochemistry. Antiendomysium antibodies (EMA) were surveyed in biopsy culture supernatants. RESULTS: A pattern of patchy duodenal lesions was observed in all untreated CD patients biopsied up to five times. High enterocyte FAS expression, and a high number of TUNEL+ and Ki67+ enterocytes were detected in areas with villus atrophy but not in those with a normal morphology (p<0.001). Conversely, EMA in culture supernatants and signs of immunological activation were present in all untreated CD biopsies. In vitro gliadin challenge increased the number of TUNEL+ and Ki67+ enterocytes (p<0.001 v cultures with medium alone) only in "flat" biopsies. Neutralising anti-FAS monoclonal antibodies were found to control gliadin induced enterocyte apoptosis (p>0.01) while agonist anti-FAS monoclonal antibody increased it (p<0.001). CONCLUSIONS: Patchy lesions are observed in untreated CD mucosa and epithelial FAS engagement is a key trigger in driving villus atrophy in CD.

Adolescent↗

Enterotoxicity and cytotoxicity of Vibrio parahaemolyticus thermostable direct hemolysin in in vitro systems.

Vibrio parahaemolyticus is a marine bacterium known to be a common cause of seafood gastroenteritis worldwide. The thermostable direct hemolysin (TDH) has been proposed to be a major virulence factor of V. parahaemolyticus. TDH causes intestinal fluid secretion as well as cytotoxicity in a variety of cell types. In this study, we investigated the interplay between the hemolysin's enterotoxic and cytotoxic effects by using both human and rat cell monolayers. As revealed by microspectrofluorimetry, the toxin causes a dose-dependent increase in intracellular free calcium in both Caco-2 and IEC-6 cells. This effect was reversible only when low toxin concentrations were tested. The TDH-activated ion influx pathway is not selective for calcium but admits ions such sodium and manganese as well. Furthermore, in the same range of concentration, the hemolysin triggers a calcium-dependent chloride secretion. At high concentrations, TDH induces a dose-dependent but calcium-independent cell death as assessed by functional, biochemical, and morphological assays.

Animals↗

Leukocyte rheology before and after chemotactic activation in some venous diseases.

OBJECTIVE: to evaluate leukocyte rheology, polymorphonuclear leukocyte (PMN) membrane fluidity and cytosolic Ca2+ concentration in subjects with post-phlebitic leg syndrome (PPS) and acute deep-venous leg thrombosis (DVT). SUBJECTS: twenty-two subjects with leg PPS and 14 subjects with leg DVT. METHODS: we evaluated the leukocyte filtration (unfractionated, mononuclear cells (MN) and PMN), the PMN membrane fluidity and the PMN cytosolic Ca2+ concentration. Subsequently, we evaluated the same PMN variables after in vitro chemotactic activation with 4-phorbol 12-myristate 13-acetate (PMA) and N -formyl-methionyl-leucyl-phenylalanine (fMLP). RESULTS: at baseline we observed a significant difference in the filtration variables of unfractionated and MN cells and in PMN cytosolic Ca2+ concentration. After activation, in normal subjects and subjects with PPS and DVT, a significant variation in PMN filtration at 5 and 15 minutes was evident. In normal subjects, no variation was present in PMN membrane fluidity or cytosolic Ca2+ concentration after activation. In subjects with PPS and DVT, we found a decrease in PMN membrane fluidity and an increase in PMN cytosolic Ca2+ concentration. After PMN activation (at 5 and 15 min) Delta% of IRFR distinguished normal subjects from subjects with PPS and DVT, while no difference was found in Delta% of membrane fluidity or cytosolic Ca2+ concentration. CONCLUSIONS: there is a functional alteration of leukocytes in these patients whose mechanisms are not yet clear.

Calcium↗

Vibrio parahaemolyticus thermostable direct hemolysin modulates cytoskeletal organization and calcium homeostasis in intestinal cultured cells.

Vibrio parahaemolyticus is a marine bacterium known to be the leading cause of seafood gastroenteritis worldwide. A 46-kDa homodimer protein secreted by this microorganism, the thermostable direct hemolysin (TDH), is considered a major virulence factor involved in bacterial pathogenesis since a high percentage of strains of clinical origin are positive for TDH production. TDH is a pore-forming toxin, and its most extensively studied effect is the ability to cause hemolysis of erythrocytes from different mammalian species. Moreover, TDH induces in a variety of cells cytotoxic effects consisting mainly of cell degeneration which often leads to loss of viability. In this work, we examined the cellular changes induced by TDH in monolayers of IEC-6 cells (derived from the rat crypt small intestine), which represent a useful cell model for studying toxins from enteric bacteria. In experimental conditions allowing cell survival, TDH induces a rapid transient increase in intracellular calcium as well as a significant though reversible decreased rate of progression through the cell cycle. The morphological changes seem to be dependent on the organization of the microtubular network, which appears to be the preferential cytoskeletal element involved in the cellular response to the toxin.

Animals↗

Bromelain prevents secretion caused by Vibrio cholerae and Escherichia coli enterotoxins in rabbit ileum in vitro.

BACKGROUND & AIMS: Diarrhea is a major cause of illness and death in children and young animals. The aim of this study was to investigate the possible therapeutic effect of bromelain, a proteolytic extract obtained from pineapple stems on bacterial toxin and second-messenger agonist-induced intestinal secretion. METHODS: The effect of bromelain pretreatment on short-circuit responses to Escherichia coli heat-labile enterotoxin, heat-stable enterotoxin, and Vibrio cholerae cholera toxin was evaluated in rabbit ileum mounted in Ussing chambers. RESULTS: Bromelain was 62% effective in preventing heat-labile enterotoxin-induced secretion, 51% effective against cholera toxin, and 35% effective against heat-stable enterotoxin [corrected]. Bromelain also prevented secretory changes caused by prostaglandin E2, theophylline, calcium-ionophore A23187, 8-bromoadenosine 3':5'-cyclic monophosphate, and 8-bromoguanosine 3':5'-cyclic monophosphate, well-known intracellular mediators of ion secretion. The efficacy of bromelain was not caused by reduced tissue viability resulting from its proteolytic effects on enterocytes, indicated by experiments measuring uptakes of nutrients into intestinal cells and experiments measuring short-circuit responses to glucose. CONCLUSIONS: Bromelain prevents intestinal fluid secretion mediated by secretagogues that act via adenosine 3':5'-cyclic monophosphate, guanosine 3':5'-cyclic monophosphate, and calcium-dependent signaling cascades. It may be clinically useful as an antidiarrheal drug.

Animals↗

Treatment of visceral leishmaniasis in children with liposomal amphotericin B.

We used liposomal amphotericin B as first-choice treatment of visceral leishmaniasis in 106 immunocompetent children who acquired the infection in a temperate region of southern Europe (Italy) where Leishmania infantum visceral leishmaniasis is endemic. The aim of the study was to identify the minimum total dose of liposomal amphotericin B needed to cure the infection in children and reduce the period of hospitalization. We conclude that the optimal regimen in immunocompetent children with L. infantum visceral leishmaniasis to be a total dose of 18 mg/kg of liposomal amphotericin B (3 mg/kg per day for 5 days, followed by 3 mg/kg administered as an outpatient regimen on day 10).

Adolescent↗