Organization of the trigeminal and facial motor nuclei in the hagfish, Eptatretus burgeri: a retrograde HRP study

We studied the trigeminal and facial motor nuclei of the hagfish by the retrograde HRP method. We distinguished 4 components in a single column of the motor nuclei of the trigeminal nerve and the facial nerve, viz., the pars magnocellularis of the trigeminal motor nucleus (mVm), the anterior part of the pars parvocellularis of the trigeminal motor nucleus (mVp1), the posterior part of the pars parvocellularis of the trigeminal motor nucleus (mVp2) and the facial motor nucleus (mVII). Although in Nissl preparations only the mVm could be distinguished from the rest of the nucleus, the boundaries of the other 3 components were clearly demarcated in HRP preparations. Intramuscular injections into two representative antagonistic jaw muscles revealed that there was no apparent topological organization of the neurons pertaining to the opening and closing muscles in the mVm and mVp1, but both antagonistic muscles were innervated bilaterally. Although the hagfish does possess a cartilaginous jaw, the organization pattern of the motor nuclei of the jaw muscles seems to be the most primitive of all living vertebrates.     

Lack of stereoselectivity in the inotropic and phosphodiesterase inhibitory effects of saterinone enantiomers

The enantiomers of the positive inotropic and a1-adrenoceptor blocking agent saterinone (+/-)-1,2-dihydro-5-[4-[2-hydroxy-3- [4-(2-methoxyphenyl)-1-piperazinyl]propoxy] phenyl]-6-methyl-2-oxo-3-pyridine-carbonitrile, BDF 8634) have been investigated with in vitro and in vivo models in laboratory animals. In the guinea pig papillary muscle, saterinone enantiomers had equipotent inotropic activity and were also as potent as racemic saterinone; the (R)-enantiomer, however, exhibited a greater efficacy than the related compounds. Saterinone and its enantiomers were equipotent in the inhibition of phosphodiesterase PDE III activity in the guinea pig myocardium. The equipotent inotropic effects were also observed after parenteral and enteral administration in cats. In receptor binding studies, (S)-saterinone was 10-fold more potent than (R)-saterinone by inhibiting [3H]-prazosin binding to specific alpha 1-adrenoceptor sites in rat brain cortex membranes. However, in the isolated thoracic aorta of the rabbit, (S)-saterinone was only 3-fold more potent than (R)-saterinone at preventing the pressor effects of phenylephrine. When the enantiomers were tested in vivo against the pressor effects of phenylephrine in the pithed rat, (S)-saterinone was only 2-fold more potent than (R)-saterinone in its alpha 1-adrenoceptor blocking potency. Thus the enantiomers of saterinone do not display enantio-selectivity in their inotropic and PDE III inhibitory effects in vitro, nor in their cardiotonic effects in vivo. There is a slight enantio-selectivity at alpha 1-adrenoceptors in receptor binding studies, but this is reduced to biologically irrelevant magnitude in functional studies in vitro and in vivo.     

Rupture of the supradiaphragmatic inferior vena cava by blunt decelerating trauma: case report

Lacerations of the inferior vena cava resulting from blunt external trauma are relatively rare, but extremely serious. The high lethality is due to the difficulty in diagnosis and technical problems with repair, particularly if the injury is located above the renal veins. During a 12-month period seven patients with inferior vena cava laceration were seen, of whom two presented with laceration of the inferior vena cava above the diaphragm. Both had a deceleration injury while wearing seatbelts. The clinical presentation was similar. The etiology is discussed. Caval continuity should be repaired because acute sudden occlusion at the suprahepatic level is incompatible with survival. Median sternotomy is advised, moreover it provides good exposure for eventual cannulation.     

Parathyroid imaging. Use of dual isotope scintigraphy for the localization of adenomas before surgery.

Seventy-nine patients with primary hyperparathyroidism, whose average preoperative blood calcium level was 11.6 mg/dl, underwent thallium-technetium dual isotope scintigraphy of the thyroid and parathyroids. For patients who had surgery, the detection and localization rate of parathyroid disease or the sensitivity was low (0.53), but the positive predictive value for the location was high (0.80). Correct localization correlated positively with the weight of the tumor but not significantly with the parathyroid hormone blood level nor with the blood calcium level. Unprocessed data alone were sufficient to predict correctly the location in two thirds of the detected cases. Computer processing increased the sensitivity without decreasing the specificity. Those results, at variance with earlier published data but congruent with another more recent study, require a reevaluation of the role of this scintigraphic technique in the management of hyperparathyroidal patients.     

Whole-body inflammation in trauma patients. An autopsy study

In a review of autopsy specimens and reports in 35 trauma cases, we found signs of generalized inflammation and tissue damage with increases in organ weights in organs not primarily injured. These abnormalities occurred independent of the time of death and were also found in patients who died of brain injury alone. The most pronounced signs of inflammation and increases in organ weights were found when the adult respiratory distress syndrome, hypovolemic shock, or multiple organ failure were the causes of death. These findings are similar to those found in several organs of rabbits after four hours of complement activation in combination with 20 minutes of hypoxia. Therefore, the autopsy findings in this series of trauma patients might represent the morphologic features of adult respiratory distress syndrome and multiple organ failure in an early, preclinical stage.     

Monitoring the protective effects of minocycline treatment with radiolabeled annexin V in an experimental model of focal cerebral ischemia.

Minocycline is an antibiotic now recognized to have antiapoptotic and antiinflammatory properties. Because of these properties, minocycline may be of benefit in reducing neuronal apoptosis from ischemia and subsequent postischemic inflammation if administered soon after a stroke. We now explore the feasibility of using (99m)Tc-annexin V, an in vivo marker of apoptosis, with SPECT to monitor the antiapoptotic effects of minocycline therapy. METHODS: CB6/F1 adult male mice underwent unilateral distal middle cerebral artery occlusion (dMCA) occlusion and were imaged and sacrificed at 1, 3, 7, or 30 d after injury. Animals were given minocycline (or vehicle) 30 min and 12 h after dMCA occlusion and then given 22.5 mg/kg twice daily for up to 7 d. Before imaging, behavioral tests were performed to evaluate the neurologic function. After imaging, brains were collected for histology and assessed for the degree of apoptosis and microglial activation. RESULTS: (99m)Tc-Annexin V uptake in injured hemispheres was significantly decreased 2- to 3-fold by minocycline at all time points. Minocyline reduced infarct size as seen histologically and improved behavioral indices as late as 30 d. Infarct volume as seen histologically correlated with radiolabeled annexin V uptake seen by SPECT. In situ fluorescent microscopy demonstrated that annexin V bound primarily to neurons at 1 and 3 d, with a shift toward microglia by 7 and 30 d. CONCLUSION: We found that minocycline significantly reduces neuronal apoptosis and infarct size and improves neurologic outcome in mice after acute focal cortical ischemia.