ABSTRACT
In this study terminal cisternae vesicles from rabbit skeletal muscle were fused into planar bilayers and the effect of calmodulin on single Ca2+ release channel currents was investigated. In the presence of 10(-7) and 10(-9) M free [Ca2+], nanomolar concentrations of calmodulin activated the channel by increasing the open probability of single-channel events in a dose dependent manner. The activatory effect of calmodulin was reversed by 10 microM ruthenium red. At 10(-5) M free [Ca2+], calmodulin (0.1-1 microM) inhibited channel activity. Calmodulin overlays were carried out using concentrations of Ca2+ similar to those used for the planar lipid bilayer assays. In the presence of 10(-7) M [Ca2+], calmodulin bound to the ryanodine receptor, to a region defined by residues 2937-3225 and 3546-3655. These results suggest that calmodulin may activate the Ca(2+)-release channel (ryanodine-receptor) by interacting with binding sites localized in the central portion of the RYR protomer.
Subject(s)
Calcium Channels/metabolism , Calcium/metabolism , Calmodulin/pharmacology , Muscle Proteins/metabolism , Muscle, Skeletal/drug effects , Animals , Calmodulin-Binding Proteins/metabolism , Lipid Bilayers , Muscle, Skeletal/metabolism , Rabbits , Ruthenium Red/pharmacology , Ryanodine Receptor Calcium Release ChannelABSTRACT
The authors report on a new method for arthrodesing both the subtalar and ankle joints simultaneously. The technique uses a cannulated screw driven from the plantar aspect of the calcaneus and directed proximally through the subtalar and ankle joints. An inverted strut graft further supports and reinforces the ankle component anteriorly. Although one patient fractured the calcaneal-talar-tibial screw at 13 months postoperative, overall results of the five cases evaluated were excellent. Patient follow-up ranged from four to 54 months, with an average of 26 months.
Subject(s)
Ankle Joint/surgery , Arthrodesis/methods , Subtalar Joint/surgery , Adult , Aged , Bone Screws , Calcaneus/surgery , Equipment Failure , Fibula/surgery , Follow-Up Studies , Humans , Middle Aged , Talus/surgery , Tibia/surgeryABSTRACT
In our work we have an enumeration of 1527 sedation cases to carry out RM exams with non co-operating patients, most of them in pediatric age. During the examination the patients were monitored using oximeter and observed by closed circuit camera. The meaningless complications head us to think that deep sedation is a reliable procedure which allows us to work out RM exams during a day-hospital regime.
Subject(s)
Conscious Sedation , Magnetic Resonance Imaging , Adolescent , Adult , Aged , Child , Child, Preschool , Evaluation Studies as Topic , Humans , Infant , Infant, Newborn , Middle AgedABSTRACT
The authors report an anomalous tendon during routine cadaver dissection. This accessory peroneus brevis tendon arose with the peroneus brevis muscle. The tendon passed through a channel in the peroneus tertius and inserted into the extensor hood apparatus of the fifth digit.
Subject(s)
Foot Deformities, Congenital/pathology , Tendons/abnormalities , Cadaver , HumansABSTRACT
The rotational pedicle graft, as adapted for use on the plantar aspect of the foot, is a valuable tool for repairing painful defects of the weight-bearing surface. The procedure described here lends itself particularly well to repair of defects beneath the second and third metatarsophalangeal joints, although it also has application on the heel and other weight-bearing surfaces.
