Biomedical subjects

D Lüscher

Publications and source records attributed to D Lüscher.

7 recordsLinked to original sources

PubMed1997

[Why is iodine deficiency once again present in the Berne region?].

Owing to the progressive iodination of salt in Switzerland (5, 10, 20 mg KI/kg in the years 1922, 1965, 1980), iodine deficiency in former endemic goiter regions had nearly disappeared. In several areas of the country, urinary iodine had increased from below 30 micrograms/24 h (1920) to > 100 micrograms/g creatinine (1981-1990). In 1991-1992, however, the 24-h-iodinuria in a subgroup of 160 examinations out of a total of 289 persons in Berne was again insufficient (norm > 150 micrograms J/24 h): mean 121 micrograms/24 h (82 micrograms/l), median 107.8 micrograms/24 h (67 micrograms/l). Follow-up of one proband in 1991-1992 (n = 9) and 1996 (n = 11) yielded average 24-h-iodinurias in the slightly deficient domain of (mean +/- SD) 104 +/- 57 micrograms/ 24 h (75 +/- 30 micrograms/l) and 103 +/- 27 micrograms/24 h (44 +/- 17 micrograms/l) respectively, with a wide range (45-258 micrograms l/24 h globally). Possible reasons for the decreasing iodide intake in recent years, resulting in the 1990s in a marginally deficient supply, are reduced intake of salt in recent decades, increased consumption of foodstuffs prepared with non-iodized salt, dietary diversification, and frequent meals away from the family table. Therefore, intake of non-iodized salt should be avoided in Switzerland.

Adult↗

PubMed1995

The instability of dietary iodine supply over time in an affluent society.

In the Bernese region, where goiter was formerly endemic, alimentary salt has been supplemented by increasing amounts of potassium iodide (KI): 5, 10, 20 mg KI/kg in 1922, 1965 and 1980 respectively. Ioduria rose from < 30 micrograms I/g creatinine in 1920 to > 100 micrograms I/g creatinine in the 1980s. In 1992 ioduria was estimated in 55 healthy volunteers (group A and individual B) and 234 thyroid carcinoma patients after thyroidectomy: hypothyroid patients with (C) and without thyroid remnants (D) and euthyroid patients on T4 substitution (E). The arithmetic mean iodine excretion of the healthy volunteers in group A and individual B was found to be 87 +/- 40 micrograms I/g creatinine. This is insufficient according to the recommendations of the WHO. In all groups, the iodine excretion reached the recommended level only in some members: 24% (A, B), 19% (C), 38% (D) and 81% (E). It was thought in the 1980s that in a formerly iodine-deficient society, iodinated salt would continue to provide an adequate supply of iodine. However, iodine intake in this affluent society has proved to be unstable. This can be attributed to modifications of eating habits, which include a reduction of total salt consumption, combined with a growing consumption of manufactured food of cosmopolitan origin, prepared using salt containing little or no iodine.

Adolescent↗

PubMed1995

Optimal sampling times for OIH-clearance calculations using a two-compartment/two-sample method.

Orthoiodohippurate (OIH) clearance data obtained with the two-compartment/two-sample method of Lear which uses varying sampling time combinations, were compared with those of the reference two-compartment/multi-sample method of Sapirstein. A total of 35 studies were performed in 33 adult patients. The OIH clearance values determined by the reference method ranged from 107 to 883 ml/min/1.73 m2, with a median of 406 ml/min/1.73 m2. It was ascertained that the precision of the Lear method is partially dependent upon the sampling time combination. The most reliable results with the Lear method in this patient population were obtained by taking a first sample at approximately 8 min p.i., and a second sample at 32 min p.i. or later.

Adult↗

PubMed1994

Detection of shigellae, enteroinvasive and enterotoxigenic Escherichia coli using the polymerase chain reaction (PCR) in patients returning from tropical countries.

We have used the polymerase chain reaction (PCR) to detect shigellae, EIEC and ETEC in stool specimens of diarrhoeic patients returning from tropical countries. As compared to culture (7.1% positive specimens), which recognizes only Shigella strains, PCR performed on bacterial growth from directly inoculated MacConkey agar plates and directed against virulence-associated genes present in both Shigella and EIEC was positive in 19.8% of the samples. We assumed that these additional positive results represent true rather than false positive samples because identical results for each single specimen were obtained using two different PCR systems and because positive results (culture as well as PCR) were exclusively found in patients with recent travel but not in those who acquired diarrhoea in a developed country where these organisms are not endemic. PCR detecting LT- and ST-specific sequences was positive in 18.5% of the patients with recent travel. Again no positive cases were identified in controls. Combining PCR and culture results, at least one bacterial pathogen was found in more than 50% of the patients with recent travel. We conclude that PCR is superior to culture methods for the detection of Shigella, EIEC and ETEC in travel-associated diarrhoea.

Aeromonas↗

PubMed1994

Dual-isotope SPET 201Tl rest/99mTc-MIBI stress: one-day protocol for pre-operative myocardial imaging?

We compared the results of a rest 201TI/stress 99mTc-MIBI protocol, both by means of separate single isotope and simultaneous dual isotope acquisition, with a standard stress/rest 99mTc-MIBI 2-day protocol in 11 patients with low probability of CAD and 14 patients with chronic CAD. In patients with CAD 406 segments (sgs) were analysed. In the standard protocol 119 sgs were classified as pathological of which 50.4% were fixed and 49.6% reversible defects. With the MIBI-stress/TI-rest single 33% of 119 pathological sgs were fixed and 67% reversible defects. With the MIBI-stress/TI-rest dual only 20% were fixed and 80% reversible defects. The reversibility of 59 MIBI-stress/MIBI-rest reversible defects was quantified: MIBI-stress/MIBI-rest 35 +/- 16% MIBI-stress/TI-rest single 50 +/- 26% and MIBI-stress/TI-rest dual 48 +/- 22%. The results of 99mTc-MIBI rest and 201TI rest studies in patients with chronic CAD are not the same. Dual-isotope 1-day 201TI-rest/99mTc-MIBI-stress SPET data, acquired separately, may give fast and complete information on myocardial perfusion at stress and rest, respectively, and on myocardial viability.

Female↗

PubMed1992

[Bacterial pathogens in diarrhea: demonstration of verotoxin-producing Escherichia coli using the polymerase chain reaction].

In 23% of 576 diarrhea patients we were able to demonstrate putative bacterial pathogens. Not included in this number is Clostridium difficile which was found in 8 of 48 (8.3%) specimens analyzed. In addition to Salmonella (8.2%), Campylobacter (6.0%), Aeromonas (2.7%), Shigella (1.9%) and Yersinia (0.8%) we identified verotoxin-producing Escherichia coli (VTEC) in 10 patients (1.9%). VTEC were found as frequently as Shigella (occurring exclusively in patients returning from the tropics) and we propose that VTEC should be routinely assayed in patients with travel-associated diarrhea as well as in those with diarrhea presumably acquired in Switzerland. Established methods for identification of E. coli O157:H7, which include screening for sorbitol-negative Enterobacteriaceae and agglutination, are laborious and insensitive (only 1 of 10 patients with proven VTEC infection positive). The other 9 patients were identified by means of the polymerase chain reaction (PCR). In 7 of these 9 patients we were able to isolate a verotoxigenic strain following a positive PCR result by screening large numbers of colonies. None of them belonged to the O157:H7 serogroup and, in addition, all were sorbitol-positive. The polymerase chain reaction as performed in this study is easy to use, is applicable to large numbers of specimens, and can be regarded as the method of choice for demonstration of VTEC in the clinical diagnostic laboratory.

Adult↗

PubMed1992

[Long-term course in differentiated thyroid gland carcinoma].

545 patients with differentiated thyroid carcinoma were followed up for periods ranging up to 25 years after first treatment (mean 8.1 years, 65% for over 5 years). 72% of patients with papillary carcinoma (n = 270), but only 52% with follicular carcinoma (n = 275) remained tumor-free during the further course. Residual malignancies persisted for more than the first year in 6% and 17% of patients respectively; there were tumor recurrences after an apparently tumor-free interval in 22% and 31% respectively, the latest after 12 and 27 years respectively. 6% and 19% of patients respectively died as a direct result of the tumor (and a group of equal size from other causes), half due to residual and half due to recurrent carcinoma. With regard to residual tumors, few significant risk factors were found preoperatively, comprising distant metastases (factor = 34 and 20 for papillary and follicular tumors respectively), age over 50 years (F = 6.4 and 5), infiltrating growth of primary tumor (F = 4 and 4.3), and regional lymph node involvement (F = 1.2 and 2). However, these factors were of little use in predicting the risk of the more frequently observed tumor recurrence, with maximum factors of 2 (for T4 and N+ stage) for papillary thyroid cancers and 1.5 for follicular cancers. At risk for recurrence were patients in whom total thyroidectomy was not performed (F = 2.3 and 2) and those who did not receive postoperative radioiodine treatment (F = 3), irrespective of age and tumor stage. Therefore, any individualizing regimen beginning with the first treatment has a bearing not only on residual tumor's 50% contribution to mortality. The equally large contribution of recurrences to tumor death can be influenced only by thyroidectomy or, more realistically, by strumectomy combined with early ablation of thyroid remnants with radioiodine. Postoperative radiotherapy of the neck region did not prevent tumor recurrence, and although hormonal suppression was never given the results compared well with the best of published long-term follow-up studies. There were no acute or late complications that could be ascribed to radioiodine treatment. However, a strict strategy of the reducing the administered doses was adopted: the ablation dose was half that used previously (1.5 GBq, i.e. 45 mCi on average), tumor treatment was halted even where residual uptake was observed scintigraphically (in 44% of patients treated) and radioiodine was no longer used for follow-up investigations.(ABSTRACT TRUNCATED AT 400 WORDS)

Adenocarcinoma↗