Revascularization of the Posterior Circulation

The primary objective of revascularization procedures in the posterior circulation is the prevention of vertebrobasilar ischemic stroke. Specific anatomical and neurophysiologic characteristics such as posterior communicating artery size affect the susceptibility to ischemia. Current indications for revascularization include symptomatic vertebrobasilar ischemia refractory to medical therapy and ischemia caused by parent vessel occlusion as treatment for complex aneurysms. Treatment options include endovascular angioplasty and stenting, surgical endarterectomy, arterial reimplantation, extracranial-to-intracranial anastomosis, and indirect bypasses. Pretreatment studies including cerebral blood flow measurements with assessment of hemodynamic reserve can affect treatment decisions. Careful blood pressure regulation, neurophysiologic monitoring, and neuroprotective measures such as mild brain hypothermia can help minimize the risks of intervention. Microscope, microinstruments and intraoperative Doppler are routinely used. The superficial temporal artery, occipital artery, and external carotid artery can be used to augment blood flow to the superior cerebellar artery, posterior cerebral artery, posterior inferior cerebellar artery, or anterior inferior cerebellar artery. Interposition venous or arterial grafts can be used to increase length. Several published series report improvement or relief of symptoms in 60 to 100% of patients with a reduction of risk of future stroke and low complication rates.     

Lymphatic absorption and metabolism of orally administered testosterone undecanoate in man

Summary [³H]-testosterone undecanoate ([³H]TU) was administered orally to 4 patients with a thoracic duct catheter after neck dissection surgery.Appearance of radioactivity in lymph, plasma and urine was measured at different times. Metabolites of TU in these fluids were investigated. Peak levels of radioactivity appeared simultaneously in lymph and plasma (2.5–5 h after administration) while the excretion in urine was highest approximately 2 h after the plasma and lymph peak. The main compounds appearing in the lymph were TU and 5-dihydrotestosterone undecanoate (5-DHTU), but 5-DHTU could not be detected. In plasma almost all metabolites were probably conjugated.During the first 24 h approximately 40% of the administered radioactivity was excreted in the urine. The total amount of radioactivity excreted in the urine during the first week was 45–48%. The predominant urinary metabolites were testosterone- and androsterone-glucuronide.The results indicate that TU is metabolized partly in the intestinal wall. The remaining TU and newlyformed 5-DHTU, at least partly, are absorbed via the lymphatic system.     

The Redox Modulating Sonlicromanol Active Metabolite KH176m and the Antioxidant MPG Protect Against Short-Duration Cardiac Ischemia-Reperfusion Injury

Cardiovascular Drugs and Therapy - Sonlicromanol is a phase IIB clinical stage compound developed for treatment of mitochondrial diseases. Its active component, KH176m, functions as an antioxidant,...     

Effect of different growth hormone-releasing factors on the concentrations of growth hormone, insulin and metabolites in the plasma of sheep maintained in positive and negative energy balance

Three experiments were conducted to compare the ability of different preparations of growth hormone-releasing factor (GRF) to stimulate GH secretion in sheep maintained in positive and negative energy balance. In experiment 1 five sheep were injected (i.v.) with three preparations of human pancreatic GRF (hpGRF-44, hpGRF-40, hpGRF-29-NH2) and one preparation of rat hypothalamic GRF (rhGRF-29-NH2) all at 98.0 pmol/kg, or control vehicle, in a Latin square design when the animals either had free access to food or were fed half their maintenance requirements. Analysis of plasma samples, obtained before and for 150 min after injection, revealed that the reduced food intake resulted in the expected changes in body weight and circulating GH, insulin, glucose, urea and non-esterified fatty acids. The maximum post-injection concentrations of GH did not differ between either the two levels of feeding or the four GRF preparations but the mean post-injection concentration of GH was significantly higher for all GRF treatments on the restricted ration (P less than 0.001). The mean post-injection response to rhGRF-29-NH2 was less than that obtained with hpGRF-44 for sheep with food available ad libitum (P less than 0.05) and was clearly more persistent for all GRF treatments in animals fed the reduced diet (P less than 0.001). In experiment 2 the same five sheep were injected i.v. with rhGRF-29-NH2 (98.0 pmol/kg) when they had free access to food and after food had been withdrawn for 3 days.(ABSTRACT TRUNCATED AT 250 WORDS)     

Comparison of assessment tools to score recovery of function after repair of traumatic lesions of the median nerve

In this paper the recovery after repair of the median nerve has been used to compare different assessment tools for evaluation of peripheral nerve function: touch (moving 2-point discrimination (2PD); Semmes-Weinstein (SW) monofilament, motor (Medical Research Council (MRC) scale), combined motor and sensory (Dellon modification of the Moberg pick up test; Moberg Recognition test), and pain (visual analogue scale; pinprick-test). The mean (SD) age of our 28 patients was 28 (12) years. The mean (SD) follow-up period was 5 years, 2 months (2 years, 8 months). On the operated side three patients (11%) had a moving 2PD of less than 4 mm. The results of the moving 2PD were compared with those of the SW monofilaments, but with a poor correlation. The MRC score correlated well with opposition movement of the thumb and muscle wasting (p<0.01). We recommend a number of tests to evaluate (the chronological return of) peripheral nerve function.     

Clinical use of nerve conduits in peripheral-nerve repair: review of the literature

The use of nerve conduits has evolved from a previous experimental idea to a clinical reality over the last ten years. An overview of the literature on the clinical use of nerve conduits in peripheral-nerve repair is presented.