Health, risk behaviour and consumption of addictive substances among physicians - results of an online survey.

BACKGROUND: Previous studies were able to show that hazardous alcohol and substance abuse among physicians is not rare. Currently no recent data to detect risk groups are available either on the prevalence of hazardous drinking disorders and risky health behaviour among physicians or on influencing factors (age, gender, role, institution, specialization, working hours). METHODS: A 42-item online questionnaire was distributed to 38 university hospitals, 296 teaching hospitals and 1290 physicians in private practice. The questionnaire addressed health behaviour and alcohol/substance consumption as well as demographic and work-related properties. RESULTS: Out of 1338 a total of 920 questionnaires could be evaluated. 90% of physicians estimate their health status as satisfying. 23% of doctors consume hazard quantities of ethanol, 5% are nicotine addicted, and 8% suffer from obesity. Childlessness (p = 0,004; OR = 1,67; KI = 1,17-2,37) for both genders and the role of a resident for females (p = 0,046, OR = 3,10, KI = 1,02-9,40) poses a risk factor for hazardous alcohol consumption. Weekly working hours of more than 50 h (p = 0,009; OR = 1,56; KI = 1,12-2,18) and a surgical profession (p < 0,001; OR = 2,03; KI = 1,47-2,81) may also be a risk factor towards hazardous and risky health behaviour. CONCLUSION: A more structured and frequently repeated education on help offerings and specific institutions for addicted and risk groups seems essential.

Ultrastructural and molecular biologic comparison of classic proprioceptors and palisade endings in sheep extraocular muscles.

PURPOSE: To analyze and compare the structural and molecular features of classic proprioceptors like muscle spindles and Golgi tendon organs (GTOs) and putative proprioceptors (palisade endings) in sheep extraocular muscle (EOMs). METHODS: The EOMs of four sheep were analyzed. Frozen sections or wholemount preparations of the samples were immunohistochemically labeled and analyzed by confocal laser scanning microscopy. Triple labeling with different combinations of antibodies against neurofilament, synaptophysin, and choline acetyltransferase (ChAT), as well as alpha-bungarotoxin and phalloidin, was performed. Microscopic anatomy of the nerve end organs was analyzed by transmission electron microscopy. RESULTS: The microscopic anatomy demonstrated that muscle spindles and GTOs had a perineural capsule and palisade endings a connective tissue capsule. Sensory nerve terminals in muscle spindles and GTOs contained only a few vesicles, whereas palisade nerve terminals were full of clear vesicles. Likewise, motor terminals in the muscle spindles' polar regions were full of clear vesicles. Immunohistochemistry showed that sensory nerve fibers as well as their sensory nerve terminals in muscle spindles and GTOs were ChAT-negative. Palisade endings were supplied by ChAT-positive nerve fibers, and the palisade complexes including palisade nerve terminals were also ChAT-immunoreactive. Motor terminals in muscle spindles were ChAT and alpha-bungarotoxin positive. CONCLUSIONS: The present study demonstrated in sheep EOMs that palisade endings are innervated by cholinergic axons exhibiting characteristics typical of motoneurons, whereas muscle spindles (except the polar regions) and GTOs are supplied by noncholinergic axons. These results raise the question of whether palisade endings are candidates for proprioceptors in EOMs.

Is there a double innervation of the tensor tympani muscle in humans?

The middle ear muscles and their function have not yet been fully explored. The statement of Lawrence, for example, that the tensor tympani muscle of humans might have a dual innervation has never been proven or disproven. The question is of great interest; in our opinion, it represents one of the key questions in the putative afferent feedback loop of the middle ear muscles in humans. A light microscopic study was performed on 16 tensor tympani muscles taken from 11 cadavers. Six muscles were taken out in toto and stained according to the modified method of Sihler. The remaining 10 muscles were dehydrated and embedded in paraffin. In 5 of these muscles, complete transverse serial sections were made on a microtome at 7 microm and alternately stained by silver impregnation, S-100 protein immunohistochemistry, and ferric oxide. In the remaining 5 muscles, complete longitudinal serial sections were made at 10 microm. These sections were alternately stained by the methods of Cason and Maskar. Neither the surgical microscopic investigation nor the light microscopic investigation revealed any innervation to the human tensor tympani muscle other than the one arising from the mandibular branch of the trigeminal nerve. Our findings, apart from the fact that they clearly refute an unproven hypothesis, might represent another small step toward understanding the innervation of the tensor tympani muscle.