Developing effective screening strategies in multiple endocrine neoplasia type 1 (MEN 1) on the basis of clinical and sequencing data of German patients with MEN 1.

BACKGROUND: Multiple-endocrine-neoplasia-type-1 (MEN1) is an autosomal-dominant inherited disorder characterized by the combined occurrence of primary hyperparathyroidism (pHPT), gastroenteropancreatic neuroendocrine tumors (GEP), adenomas of the pituitary gland (APA), adrenal cortical tumors (ADR) and other tumors. As the tumors appear in an unpredictable schedule, uncertainty about screening programs is persisting. OBJECTIVE: To optimize screening and to analyze possible differences in sporadic versus familial cases. METHODS: We analyzed data of 419 individuals including 306 MEN-1 patients (138 isolated and168 familial cases out of 102 unrelated families). RESULTS: A total of 683 tumors occurred consisting of 273 pHPT, 138 APA, 166 GEP, 57 ADR, 24 thymic- and bronchial-carcinoids as well as 25 neoplasms of other tissues. The age-related penetrance was determined as 10%, 35%, 67%, 81% and 100% at 20, 30, 40, 50 and 65 years respectively. Although pHPT being the most frequent first manifestation (41%), also GEP (22%) or APA (21%) were found to be the first presentation. APA occurred significantly more frequent (p<0,05) in isolated (n=138) than in familial (n=168) cases, whereas GEP showed a tendency to occur more often in familial cases. Genotype/phenotype correlation in 140 clinically affected MEN-1 cases showed a tendency for truncating mutations, especially nonsense mutations to be associated to GEP and carcinoids of the lungs and thymus. CONCLUSION: In view of the morbidity and frequency in familial cases an effective screening programme should aim at an early diagnosis of GEP particularly when truncating, especially nonsense mutations are found.

Virtual simulation in patients with breast cancer.

BACKGROUND: Investigation of the feasibility and effectiveness of virtual simulation in patients receiving radiotherapy of the breast. METHODS: Twenty-three patients were included in the study. All of them underwent a course of postoperative tangential breast irradiation. The patients were prospectively randomised into two groups. Group A patients (n=11) received a conventional computed tomography -based treatment planning, group B patients (n=12) a virtual simulation. The results of both treatment planning procedures were compared. RESULTS: The treatment planning was feasible in all patients. The time expenditure could be reduced from a median of 45.0 to 16.5 min and from 55.0 to 32.0 min for the technician and physician, respectively, using virtual simulation. Furthermore the treatment planning for the patient could be reduced from a median of 45.0 min in two sessions to 16.5 min in one session. The image quality of the digital reconstructed radiographs was satisfying compared to the simulation films. The incidence and extension of set-up corrections for the patients at the first treatment were comparable in both groups. The time interval between the planning CT and the first treatment could be reduced by 31% using virtual simulation due to the omission of the conventional simulation. CONCLUSION: The virtual simulation is a feasible tool for the treatment planning of patients undergoing tangential irradiation of the breast. Compared with the conventional simulation procedure virtual simulation is superior regarding to the precision of patients marking, the quality of the reference images and, the time expenditure for the patients and medical staff.

Bombardier beetle based biosensor.

A biosensor constructed by combining an oxygen electrode with the liquid ejected by bombardier beetles (Pheropsophus aequinoctialis) immobolized on a collagen membrane is developed for hydrogen peroxide. The sensor presents a linear range of 2.0 x 10(-4)-2.0 x 10(-3) M and a reproductibility of approximately 2%. It shows a better lifetime than similar ones employing purified catalase. The selectivity is good since other enzymes are not present in the natural source employed.

Utah's parent, teacher, and physician sealant awareness surveys.

PURPOSE: The Year 2000 Oral Health Objective 13.8 reads, "Increase to at least 50% the proportion of children who have received protective sealants on the occlusal surfaces of permanent molar teeth." In order to develop the next phase of Utah's continuing sealant promotion program directed towards meeting this objective, the Dental Health Bureau surveyed parents, teachers, and physicians in 1992. METHODS: Parents of 3,355 first- and sixth-grade students in a stratified random sample of 25 Utah urban and rural schools were surveyed to determine sealant awareness and placement. In 20 elementary urban and rural schools, 471 teachers were surveyed to determine their source of dental health knowledge and their dental unit subject matter. Five hundred ninety-six physicians were surveyed to determine their knowledge of sealants. The results of the parent and teacher surveys were analyzed using chi-square to determine statistically significant differences between urban and rural respondents. The physician results are reported in percentages. RESULTS: The parental response rate was 32%, teacher response rate was 37%, and physician response rate was 44%. Between 73% and 81% of the parents knew about sealants and 40% to 47% have had sealants placed on a child's teeth. The most frequently mentioned source of knowledge about sealants was the dentist or dental hygienist. Fewer rural than urban parents had heard about dental sealants and had insurance that covered sealants. Of the teachers who taught dental health, most taught brushing/flossing, sugar avoidance, and annual dental visits. Only a few taught about sealants. Most of the teachers received their information from a Dental Health Bureau newsletter or from their dentist or dental hygienist. When questioned about their knowledge of sealants, 68% of the physicians indicated they were unfamiliar with them. Eighty-four percent requested professional information and 65% requested patient information. CONCLUSIONS: The dental hygienist as a preventive healthcare professional is a frequent source of sealant information. Parents, physicians, and teachers need up-to-date oral health information. Dental hygienists can be instrumental in achieving the Year 2000 Oral Health Objective on dental sealants by promoting awareness in the public sector and by placing dental sealants.

Interaction of urea with lysozyme: study by the far and middle ultraviolet region absorption spectra.

The interaction of urea with lysozyme was studied in the 192-240 nm spectral region by spectrophotometry. The far and middle ultraviolet protein bands records undergo a non-linear "red shift" and "hypochromic effect" under urea titration. These spectral shifts are interpreted basically in terms of decreasing in molar absorptivity due to the binding of the denaturant with the protein chromophores. Two interaction mechanisms with different chromophores involvement are characterized. One of them is noncooperative and its is evidenced by the analysis either of the red shift or of the hypochromic effect showed by the protein far ultraviolet records in urea up to 2 M. This noncooperative effect is represented by two different and independent classes of binding sites in which the tryptophan side chain and the amide peptide bond unit are involved. The calculated stoichiometric constants give the values of 4.61 M-1 for K1 and of 0.078 M-1 for K2, while the site binding constants have the values of 0.852 M-1 for K1 and 0.086 M-1 for K2. The other mechanism which is detected by the middle U.V. band analysis of the protein in urea concentration up to 8 M shows high cooperativity (Hill coefficient of 2.56). Also in this case, tryptophan residues are involved in the binding process. No significant light-scattering influence on absorption measurements is found.