The basic anatomic and physiologic properties of human upper extremity muscles have been elucidated using a novel intraoperative sarcomere length measuring device in conjunction with quantitative anatomic and biomechanic models of these same muscles. We reviewed the genesis of these studies which began with development of the optical tools, validation using animal models, and application to hum...

The small hive beetle (Aethina tumida Murray) is a serious threat to beekeeping and crops that rely on honeybees for pollination. not only causes significant damage by feeding pollen honey, attacking bee brood causing stored honey ferment, but also might serve as vector of diseases. In addition, the has developed resistance pyrethroid organophosphate insecticides registered control honeybee pes...

Chronic muscle loading (overload) induces skeletal muscles to undergo hypertrophy and increase glucose uptake. Although AMP-activated protein kinase (AMPK) reportedly serves as a negative regulator of positive uptake, its role in overload-induced uptake is unclear. This study aimed determine whether AMPK regulates muscles. To this end, overload was induced through unilateral synergist ablations...

The relation between local circulation and alternate muscle activity among knee extensor synergists was determined during low-level sustained knee extension at 2.5% of maximal voluntary contraction for 60 min in seven subjects. Blood volume of rectus femoris (RF) and vastus lateralis (VL) was assessed by using near-infrared spectroscopy. Surface electromyogram (EMG) was recorded from RF, VL, an...

During the process of compensatory muscle hypertrophy, satellite cells are thought to proliferate, differentiate, and then fuse with existing myofibers. We hypothesized that early in this process changes occur in the expression of cellular markers indicative of the onset of myogenic processes. The plantaris muscles of rats were overloaded via the unilateral ablation of synergists. Groups of rat...

BACKGROUND Widespread residential pesticide use throughout the United States has resulted in ubiquitous, low-level pesticide exposure. The mix of active pesticide ingredients is changing in response to 2000-2001 regulations restricting use of the organophosphorus insecticides chlorpyrifos and diazinon. OBJECTIVES We aimed to determine the impact of U.S. Environmental Protection Agency regulat...

Interactions of peripheral inputs to the motoneuron of the kitten fetus as young as 3 weeks prenatal were studied by reflex discharge from the ventral root as well as by recording from single motoneurons. Facilitation was found between two synergists in fetuses 1 to 2 weeks before birth. Intracellular recording showed that the facilitation could be explained by summation of excitatory postsynap...

The leading edge of the response of Limulus ventral photoreceptors to brief flashes was investigated using a voltage clamp. The leading edge of responses increases linearly with flash intensity when dim flashes produce less than one photoisomerization per square micron of cell surface. Brighter flashes accelerate the initial portion of the response, resulting in a fourth-power relationship betw...