Prevalence of and factors associated with molar-incisor hypomineralisation in schoolchildren in the canton of Basel-Landschaft, Switzerland.

OBJECTIVES: As prevalence of molar-incisor hypomineralisation varies considerably in different countries and regions, the aim of this study was to obtain representative epidemiological data for schoolchildren living in the canton of Basel-Landschaft, Switzerland. MATERIAL AND METHODS: A representative population of schoolchildren of three different age groups, i.e. 1st grade (mean age: 7.4 years), 6th grade (mean age: 12.6 years), and 9th grade (mean age: 15.7 years) visiting compulsory schools in the canton of Basel-Landschaft, Switzerland, was examined. The presence or absence of molar-incisor hypomineralisation at time of examination was recorded as well as potential influencing factors such as age group, gender, nationality, or the children's place of residence. RESULTS: A total of 1252 schoolchildren could be included. On average, the prevalence of MIH in the study population was 14.8%. No statistically significant differences were found for nationality, gender, or place of residence. Although not statistically significant, children from the youngest age group had the highest while children from the oldest age group had the lowest MIH prevalence. CONCLUSION: With a mean value of 14.8%, MIH prevalence among schoolchildren living in the canton of Basel-Landschaft, Switzerland, is comparable to mean values recorded globally. CLINICAL RELEVANCE: This study represents the first study on MIH prevalence in Switzerland and also provides further evidence on potential influencing factors.

[Learning while studying dentistry]. / Lernen im Zahnmedizinstudium.

The aim of the present study was to gain a better understanding of the significance, use and prevalence of digital as well as analog learning and teaching aids within dentistry studies at the University Center of Dental Medicine Basel (UZB) regarding sociodemographic aspects. A questionnaire was distributed among the three upper years of dental students at the UZB in the autumn semester before the corona pandemic. The results showed that all students use digital devices. The most often used devices in connection with academic studies were portable devices such as laptops or smartphones. It is to mention that students younger than 25 years used smartphones more often as learning aids than their older classmates. The devices were used on average 57 % of the total daily use time for study purposes, whereas private usage time decreased with age and progression of studies. In order to acquire theoretical knowledge, analog and digital formats were equally important. Digital learning aids were mainly used as digitalized lecture notes or for internet research. Advantages were especially seen in timesaving and organizational aspects. The analog learning aids were appreciated for their better learning and less tiring effect. The high prevalence and usage of mobile internet connectable devices as well as the high availability of the internet may indicate a tendency toward mobile learning.

Biosensors for detecting estrogen-like molecules and protein biomarkers.

A novel evanescent-based biosensor (Endotect, ThreeFold Sensors, Inc.) was developed with laser-based fiber optics using fluorescent dye-labeled recombinant human estrogen receptor-alpha (rhERalpha) and hERbeta as probes. A three-tiered approach evaluating various steps in the formation of the estrogen-receptor complex and its subsequent activity was developed for instrument calibration to detect estrogen mimics in biological samples, water and soil. Using this approach, binding affinities and activities of certain known estrogen mimics were determined for their use as calibrator molecules. Results indicated rhERalpha and rhERbeta may be employed as probes to distinguish estrogen mimics with a broad range of affinities. In addition, application of the biosensor for detecting DNA-binding proteins in human tissue extracts was demonstrated. The later studies suggest the biosensor may be used as a clinical laboratory tool for assessing tumor marker proteins.

Low levels of sodium and potassium in the water from wetlands in Minnesota that contained malformed frogs affect the rate of Xenopus development.

Water samples were collected between 1999 and 2000 from wetlands in Minnesota that contained malformed frogs. The water samples were analyzed for 14 minerals/ions and screened for the presence of biologically active compounds using Xenopus laevis. Results indicated that water from two sites, CWB and ROI2, induced severe retardation with embryo lengths reduced 20% after 96 hr of development. The developmental delay observed with water from ROI2 was alleviated by supplementation with sodium, while both sodium and potassium alleviated the developmental delay observed with water whose mineral content mimicked that of CWB. Seasonal fluctuations in the sodium and potassium content at ROI2 and NEY correlated with changes in the rates of Xenopus development. Xenopus embryos reared on water from ROI2 for 120 hr displayed gut malformations not present in embryos reared on a synthetic media designed to mimic the mineral content of the water from ROI2. Embryos reared on water from ROI2 supplemented with minerals at levels comparable to that routinely employed in the rearing of Xenopus were neither retarded nor malformed. It is proposed that climate driven hydrology may influence the mineral composition at selected wetlands and delay development which may alter window(s) of susceptibility towards biologically active agents and the occurrence of malformed frogs.