Search PubMed⌕ Search

Biomedical subjects

R Fontana

Publications and source records attributed to R Fontana.

156 records · Page 9Linked to original sources
PubMedDate not supplied

Antibacterial and mezlocillin-enhancing activity of pure human pancreatic fluid.

The majority of deaths in severe pancreatitis are the result of superinfection of necrotic tissue. The pathogen most commonly responsible for such infections is Escherichia coli. Antibiotic prophylaxis would appear a logical precaution. The antibacterial drugs of choice should possess two basic characteristics: they must be active against the flora responsible for the infections and must be capable of penetrating into the pancreas at adequate minimum inhibitory concentrations (MICs). Mezlocillin--which is active against E. coli--has been shown to possess the latter requisite, but achieving therapeutic concentrations requires administration at high doses. In the present study, pure human pancreatic fluid showed properties similar to those observed in the dog against E. coli (bacterial colony growth 100 times lower than in a control culture) and produced a 75% reduction in mezlocillin MICs against this organism. These enhancing characteristics might make the commonly used doses sufficient for prophylactic purposes.

Colony Count, Microbial↗
PubMedDate not supplied

Rapid increase of resistance to erythromycin and clindamycin in Streptococcus pyogenes in Italy, 1993-1995. The Italian Surveillance Group for Antimicrobial Resistance.

A survey of antibiotic resistance in Streptococcus pyogenes in Italy showed a sharp increase in erythromycin resistance. In 1993, the incidence of erythromycin-resistant strains was on average 5.1%, with marked variations by geographic area. Two years later, the incidence of these strains had registered a 1.5- to roughly 20-fold increase, with a mean value of 25.9%, exceeding 40% in three centers out of 13 and 30% in another four. For all the strains studied, normal levels of susceptibility to penicillin were reported.

Anti-Bacterial Agents↗
PubMedDate not supplied

Hb-M "Hyde Park": a de novo mutation, identified by mass spectrometry and DNA analysis.

BACKGROUND: Structural hemoglobinopathies usually are inherited as autosomic dominant traits; de novo mutations are uncommon. Analytical and preparative procedures for the characterization of an abnormal hemoglobin are complex and time-consuming. Mass spectrometer analysis allows a rapid identification of the amino acid substitution. METHODS AND RESULTS: A cyanotic 7-year-old girl was found to have 16% methemoglobin. Laboratory data showed the presence of an abnormal hemoglobin, which was isolated by collecting the abnormal peak from DEAE and globin chains from CM52. The amino acid substitution was rapidly identified by FAB mass spectroscopic analysis, leading to the recognition of HbM Hyde Park. These data were confirmed by molecular analysis (Southern blot and DNA sequencing). Neither the parents nor a sister showed any abnormality; non-paternity was excluded by blood group serology and HLA typing. CONCLUSIONS: This is a case of HbM Hyde-Park arising as a de novo mutation. FAB mass spectroscopic analysis is a rapid and useful analytical method for identifying aminoacid substitution.

Blotting, Southern↗
PubMedDate not supplied

[Gastroesophageal reflux and respiratory pathology].

The prevalence of gastroesophageal reflux (GER) in 86 children with respiratory disease (recurrent pneumonia, chronic cough, bronchial asthma) has been evaluated by mean of prolonged (22-24 hours) esophageal pH-monitoring. The following parameters were evaluated: the total percentage of time pH < 4 and the percent time the esophageal pH was < 4 while sleeping. None of the children had gastrointestinal symptoms suggesting GER and no neurological disorder was noted in any of the studied patients. The mean age was 68.98 +/- 46.46 months (range 14-189); 53 (61.6%) males and 33 (38.4%) females were considered in the study. Atopy was evidenced in 42/86 (48.8%) children (total IgE > 2SD in 42/86 and prick tests positiveness in 32/86. A pH-metry indicating pathological GER was present in 52/86 (60.5%) children: 39/62 (62.9%) patients with bronchial asthma, 5/10 (50%) subjects with chronic cough and 8/14 (57.2%) children with recurrent pneumonia. No significant difference in the diagnosis of GER was recorded between atopic or non-atopic patients. The children with abnormal pH-metric recording were also evaluated by upper gastrointestinal series and/or endoscopy. A conventional barium radiology was performed in 44/52 patients and confirmed GER in 19/44 (43.2%). Esophagitis was evidenced in 21/46 (45.7%) studied patients. The presence of esophagitis was significantly (p = 0.032) related to the total percentage of time pH < 4, but the most significant (p = 0.002) association was with the percent time the esophageal pH was < 4 during sleep.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMedDate not supplied

Combined treatment with amphotericin-B and granulocyte transfusion from G-CSF-stimulated donors in an aplastic patient with invasive aspergillosis undergoing bone marrow transplantation.

Granulocyte transfusions from G-CSF stimulated donors were added to standard anti-infective treatment in preparation for and during allogeneic bone marrow transplantation in a young man affected by very severe acute aplastic anemia and invasive aspergillosis. Nine concentrates with a mean neutrophil content of 18.7 x 10(9)/L (2.6 x 10(8)/kg patient b.w.) were transfused before and after marrow infusion. An impressive clinical improvement was noticed after each granulocyte transfusion, although this was not always paralleled by a neutrophil increase in the peripheral blood. Engraftment (N > 0.5 x 10(9)/L and Plt > 25 x 10(9)/L) was verified at +16 and +40 days, respectively. The patient is currently in complete hematological and microbiological remission 14 months after transplantation. Granulocyte apheresis from G-CSF stimulated donors provides a high number of activated neutrophils. At the dose given (300 micrograms/day) donor tolerance to G-CSF was excellent. This new approach is indicated when life-threatening infections develop in patients exposed to prolonged severe neutropenia.

Acyclovir↗