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Notizen: Cast and rapidly quenched samples of ternary system GaTeSn in the Te rich corner were studied by means of x-ray diffraction, 119Sn Mössbauer spectrometry at 77 K, and differential scanning calorimetry. The crystallization products, the activation energy, the crystallization enthalpy, and the crystallization and glass temperatures of the amorphous phases are reported. The addition of Sn to GaTe increases the glass forming range of the binary system and the thermal stability of the amorphous phase. In the crystalline samples the divalent Sn atoms are always surrounded by Te in octahedrally coordinated environments. It is observed that the addition of Sn, above a threshold concentration, stabilizes the high temperature phase Ga2Te5 at room temperature. The Mössbauer spectra obtained on amorphous samples indicate two kinds of environments at Sn sites: one ascribed to the octahedral coordination, the other one to Sn surrounded by Te with tetrahedral coordination. The Mössbauer results are related to the calorimetric measurements: the role of Sn to stabilize the amorphous structure is discussed. The first steps of the crystallization of pure Te are modeled assuming homogeneous nucleation followed by three-dimensional interface-controlled growth of the crystal. © 2000 American Institute of Physics.

Notizen: Aim : To asses the efficacy and safety of ciclosporin in a paediatric population with inflammatory bowel disease.Patients and methods : Twenty-three Italian children treated with ciclosporin were studied retrospectively. The indications for treatment were severe unresponsive colitis, chronic active colitis or severe fistulizing Crohn's disease. The treatment duration, follow-up and causes of drug discontinuation were assessed.Results : Sixteen patients were treated intravenously for a mean time of 10 ± 7 days (1–24 days) and 19 orally for a mean time of 133 days (17–660 days). The mean follow-up of all patients was 13.2 months. Ciclosporin was totally ineffective, being discontinued for surgery, in nine of 23 patients (39%); it was discontinued for partial response in three patients (13%). During treatment, clinical remission was achieved in eight children (35%) and maintained after drug withdrawal in four (17%). In severe unresponsive colitis, urgent colectomy was avoided in 12 (85%) of 14 patients who tolerated the drug. Side-effects appeared in six of 23 patients (26%), and three (13%) required ciclosporin to be discontinued due to neurotoxicity.Conclusions : Ciclosporin shows disappointing long-term results in the treatment of refractory inflammatory bowel disease, but can play an important role in preventing urgent surgery in unresponsive severe colitis. Severe side-effects can occur.

Notizen: Nutrient malabsorption is a negative prognostic factor in acquired immunodeficiency syndrome and recent studies have shown that pancreatic insufficiency is a codetermining factor of malabsorption.〈section xml:id="abs1-2"〉〈title type="main"〉Aims:To evaluate the effectiveness of open-label oral pancreatic enzyme supplementation therapy in acquired immunodeficiency syndrome patients with fat malabsorption.〈section xml:id="abs1-3"〉〈title type="main"〉Patients and methods:Twenty-four consecutive patients with human immunodeficiency virus infection and fat malabsorption were recruited (11 males, 13 females; median age, 9.1 years). Faecal fat loss was evaluated by steatocrit assay at entry to the study (T-0), after 2 weeks (T-1) without pancreatic enzyme treatment and after a further 2 weeks (T-2) of treatment with pancreatic extracts (Creon 10 000 at a dose of 1000 units of lipase per gram of ingested dietary fat). Faecal elastase-1 and chymotrypsin were assayed at entry.〈section xml:id="abs1-4"〉〈title type="main"〉Results:Six patients (25%) had abnormally low elastase-1 and/or chymotrypsin faecal concentration. In all patients, steatocrit values were elevated at both T-0 and T-1. Five patients proved intolerant to pancreatic enzyme treatment because of the onset of abdominal pain, and therapy was discontinued. In the 19 patients who concluded the study, steatocrit values during pancreatic enzyme treatment (T-2) were significantly lower than at entry (P 〈 0.0001). At T-2, in eight of 19 patients, steatocrit values were within the normal limit and the frequency of cases cured or improved on pancreatic enzyme therapy (at T-2) was significantly higher than that observed during the previous study period without enzyme treatment (T-1) (P 〈 0.01). A positive significant correlation was found between steatocrit values at entry and the Centers for Disease Control class (P 〈 0.0005); also, the decrease in steatocrit values during pancreatic enzyme therapy (difference between steatocrit value at T-2 and steatocrit value at T-0) positively correlated with the Centers for Disease Control class (P 〈 0.05).〈section xml:id="abs1-5"〉〈title type="main"〉Conclusions:This pilot, open-label study showed that pancreatic enzyme supplementation therapy is highly effective in reducing faecal fat loss in human immunodeficiency virus-infected patients with nutrient malabsorption. Further double-blind studies must be undertaken to verify these results and, if they are confirmed, pancreatic enzymes can be added to our weapons in the fight against human immunodeficiency virus-associated nutrient malabsorption.