Age-related norepinephrine induced lipolytic response of isolated rat adipocytes

1. Groups of male Long Evans rats were sacrificed at the ages of 10, 16, 20, 24, 28, 32, 38 and 45 weeks. 2. The two epididymal fat pads from each rat in each group (4-5 rats) were excised for the preparation of adipocytes. 3. Cell suspensions were incubated in triplicate with each of seven norepinephrine concentrations ranging from 0.5694 to 569,400 nM. 4. Lipolytic responses are expressed as nmol glycerol released/microgram DNA/90 min. 5. The animals reached a peak response between the ages of 20 and 32 weeks. 6. Aging resulted in a gradual increase in the apparent affinity (Km) of the response yielding system for norepinephrine. 7. Initially an increase in the lipolytic capacity of the cells in response to norepinephrine, is observed, as reflected by the Vmax values up to an age of 20 weeks. 8. Vmax then stays relatively constant at elevated levels up to an age of 32 weeks, followed by an abrupt decrease with further aging.     

Prevalence and intensity of Thelazia spp. (Nematoda: Thelazioidea) in a Musca autumnalis (Diptera: Muscidae) population from Central Alberta

A face fly (Musca autumnalis) population near Wetaskiwin, central Alberta, Canada, was sampled 9 times from 26 July to 29 September 1988 for the early larval stages of Thelazia spp. Of 426 female flies examined, 159 (37%) contained Thelazia spp. (almost exclusively T. skrjabini), with an average worm burden of 4.2 larvae per infected fly. Prevalence ranged from 17 to 56% over 9 collections. This is the first report of Thelazia skrjabini in flies from western North America and the highest Thelazia prevalence in face flies yet reported in North America. The face fly population was also parasitized by Heterotylenchus autumnalis, with a prevalence of 5.5%.     

The Structural Organization of the HMGB1 Nuclear Protein and Its Effect on the Formation of Ordered Supramolecular Complexes

Biophysics - HMGB1 is one of the key proteins of the cell. HMGB1 performs its main functions predominantly in the cell nucleus, as an essential component of DNA–protein and multiprotein...     

A Model of Activity Generation in the Epileptic Focus

A model of activity generation in the epileptic focus was proposed based on the ideas that synchronization occurs between the oscillations that arise to regulate the resting potential level and that neuronal discharges are synchronized with slow oscillations. Four phases were identified in seizure development: an increase in slow-wave activity, high-frequency spike activity, synchronization in the presence of sharp peaks, and extinction of the seizure. The model was compared with an intraoperative electrocorticography record.