Myosin light chains and muscle pathology

We evaluated the isoform composition of heavy and light chains of myosin in single muscle fibers from patients with Duchenne dystrophy, myotonic dystrophy, or polymyositis. In all myopathic muscles, there was an increase in the proportion of intermediate fibers which, by analysis of myosin isoforms, fell into two subpopulations, one that contained both fast and slow myosin and another that contained myosin molecular hybrids. The increased proportion of intermediate (or transitional) fibers suggests changes in the equilibrium between fast and slow motor units. These changes could result from regeneration and subsequent maturation of fibers or from direct transformation of mature fibers of one type into the opposite.     

Carcinoma of the gallbladder

Gallbladder carcinoma is the fourth commonest gastrointestinal malignancy. Its growth is insidious and the majority of cases are advanced at the time of diagnosis. The recognized radiological features occur only in those with advanced disease. Cholecystectomy may be curative when carcinoma is confined to the gallbladder but the place of extensive surgery, chemotherapy or radiotherapy is unproven.     

A traveling exhibit: "Protecting the hands at work"

Information is an important and even essential step in the prevention process. An exhibition, which traditionally favours a visual approach, is a way of providing information for the public at large. The exhibition, the first to be produced under the auspices of the Claude Verdan foundation, tackles the issue in a general way. The aim is to: make people aware and encourage prevention in the work environment; situate the hand in a preventive context; show the importance of the hand as a work-tool; present the quantitative and qualitative extent of diseases and accidents of the hand; make the interest and difficulties in collecting information known (especially about professional diseases and workers not affiliated to the CNA); stimulate continuing search of information about prevention in the work environment. The exhibition presents certain aspects of the history of prevention in the working world, Swiss institutions involved, notions of epidemiology of professional diseases and accidents of the hand (obtained from the CNA files), as well as different types of available prevention. The material used is light (posters, slides, video) and thus transportable, and so can be widely used for the people concerned at their place of work....     

Dissociative anesthesia and striatal neuronal electrophysiology.

Compared with results obtained in locally anesthetized, paralyzed rats, the dissociative anesthetic ketamine did not alter either the number of spontaneously active striatal neurons or the basal firing rate of striatal neurons; 90% of these cells exhibited the type I striatal neuron waveform. Chloral hydrate anesthesia suppressed both the occurrence and the firing rate of spontaneously active type I cells, but did not alter the activity of type II striatal neurons. Cortical stimulation preferentially activated type II cells in paralyzed rats and in chloral hydrate-anesthetized rats. Thus, under dissociative anesthesia it is possible to study spontaneously active type I striatal neurons. However, a method of activation such as cortical stimulation is necessary to study type II striatal neurons.     

Ubiquitin in motor neuron disease: study at the light and electron microscope.

Several neurodegenerative diseases, including motor neuron disease (MND), are characterized by formation of abnormal cytoskeleton-derived inclusions which contain ubiquitin (Ubq). We have studied the distribution of Ubq in 26 cases of MND with light and electron microscopic immunocytochemistry. Ubiquitin-positive inclusions were found in neurons of anterior horns in most cases of amyotrophic lateral sclerosis (ALS) but were not present in other forms of MND. Ubiquitin immunoreactivity was observed in 10-15 nm intraneuronal filaments, which were not stained by antibodies to neurofilaments, and on dense bodies of dystrophic neurites throughout the neuropil of anterior horns and pyramidal tracts. Data analysis showed a trend toward lower percentage of Ubq-positive neurons in cases with longer duration of illness or lower number of neurons. A high percentage of Ubq-positive inclusions occurred in cases with an aggressive clinical course, suggesting that ubiquitination takes place at early stages of the disease.     

Urine screening practices in methadone maintenance clinics. A survey of how the results are used

The urinalysis practices of 324 methadone maintenance clinics were surveyed using a brief self-report questionnaire. Results indicate that there is wide variability in collection practices and clinic responses to positive findings. Virtually all clinics provide counseling and revocation of take-home methadone doses as a response to positive urinalysis results. However, increase in urine screening frequency, methadone dose adjustments, contingency contracting, group therapy, and eventual discharge are interventions also used. The implementation of different interventions varied as a function of clinic size, city size, region of the country, and program funding source.     

Intrafollicular blood flow during human ovulation.

Transvaginal ultrasonography with color flow mapping has been used to study changes in intrafollicular blood flow and morphology during follicular rupture and presumed ovulation in one human volunteer. Detailed monitoring started on day 11 of the menstrual cycle and the follicle began to rupture at 14.30 on day 13. This event was preceded by a defined rise and peak in the level of immunoreactive serum luteinizing hormone (LH) by 42 h and 17 h 20 min, respectively. Blood vessels were clearly visible in the inner ring of the follicle (the granulosa layer) at the time of the LH peak and part of the granulosa (probably containing the oocyte) started to detach before the follicle ruptured. The maximum value for the peak blood velocity in the inner vessels was observed 10 s after the start of follicular rupture and there was a concurrent increase in the impedance to blood flow, as reflected by the resistance index and the pulsatility index. The follicle took 14 min 29 s to empty and the corpus haemorrhagicum started to form about 1 min later. These preliminary data suggest that intrafollicular angiogenesis and changes in blood flow can be monitored by a relatively non-invasive technique. Changes in vascularity might be used to predict imminent ovulation and could possibly be identified or modified biochemically to help achieve or avoid a pregnancy.