Structural and oxo-transfer reactivity differences of hexacoordinate and pentacoordinate (nitro)(tetraphenylporphinato)cobalt(III) derivatives

The oxo-transfer catalyst (nitro)(pyridyl)cobalt(III) tetraphenylporphyrin has been reinvestigated by substitution of the distal pyridine ligand with 4-N,N-dimethylaminopyridine and 3,5-dichloropyridine. Differences in their structures and in the reactivity of the compounds toward catalytic secondary oxo transfer were investigated by FT-IR and UV-visible spectroscopy, cyclic voltammetry, X-ray diffraction, semiempirical calculations, and reactions with alkenes in dichloromethane solution. Very modest differences in the hexacoordinate compounds' structures were predicted and observed, but the secondary oxo-transfer reactivity at the nitro ligand varies markedly with the basicity of the pyridine ligand and the position of the coordination equilibrium. Oxo transfer occurs rapidly through the pentacoordinate species (nitro)cobalt(III) tetraphenylporphyrin that is generated by dissociation of the pyridine ligand and therefore is strongly related to the Hammett parameters of these nitrogenous bases. The reactive pentacoordinate species CoTPP(NO(2)) can be generated in solution by addition of lithium perchlorate to (py)CoTPP(NO(2)) by Lewis acid-base interactions or more simply by using the weaker Lewis base Cl(2)py instead of py as the distal ligand. In contrast to pentacoordinate (nitro)iron porphyrins, disproportionation reactions of CoTPP(NO(2)) compound are not evident. This pentacoordinate derivative, CoTPP(NO(2)), is reactive enough to stoichiometrically oxidize allyl bromide in minutes. Preliminary catalytic oxidation reaction studies of alkenes also indicate the involvement of both radical and nonradical oxo-transfer steps in the mechanism, suggesting formation of a peroxynitro intermediate in the reaction of the reduced CoTPP(NO) with O(2).

Efficacy and safety of zonisamide: results of a multicenter study

The safety and efficacy of zonisamide (ZNS), a new antiepileptic drug, was tested in 167 adult participants who entered a historical-controlled 16-week open label, multicenter study. The median percent reduction from baseline of partial seizures was 51.8% in the fourth month of the study (baseline median = 11.5 sz/month; treatment weeks 13-16 = 5.5 sz/month). Persons completing the efficacy study successfully were eligible for a long-term safety study; 113 entered this study. Adverse effects involved principally the CNS and were similar to those seen with other antiepileptic drugs. Four persons (3.7%) developed kidney stones and were withdrawn from the study 250-477 days after starting ZNS. Because of the high percentage of kidney stones, development of ZNS was stopped in the United States but was continued in Japan.

Bone diminution of osteoporotic females at different skeletal sites

The bone mineral density (BMD) of the radius and spine was determined by photo absorptiometry in a large number of controls (radius: n = 111; spine: n = 85; age range: 50-79 years) and osteoporotic women (radius: n = 98; spine n = 140; age range: 50-79 years) with at least one "atraumatic" vertebral compression fracture. Compared to age-matched controls, the BMD of the osteoporotic women showed the following diminutions: sixth decade: radius: -9.1%; spine: -25%; femur: -33%; seventh decade: radius: -16%; spine: -19%; femur: -23%; eighth decade: radius: -21%; spine: -20%; femur: -24%. The BMD was significantly diminished at all sites in all decades but in contrast to the radius, the difference from controls was bigger in the spine and femur in the sixth decade than in the seventh and eighth decade. In the osteoporotic women there was a significant correlation between radius BMD and age (r = -0.56; P less than 0.01) but not between spine or femoral BMD and age. The femoral neck BMD was also determined in a subset group of female controls (n = 68), patients with crush fractures of the spine without a fracture of the hip (n = 46), and in patients with fractures of the proximal femur (n = 21). There was no difference among these groups in mean age (64 +/- 7, range: 50-79 years). Patients with hip fracture and spine fracture showed bone diminution in all three regions that was significantly below controls (P less than 0.001).(ABSTRACT TRUNCATED AT 250 WORDS)

The influence of barbiturates on cerebral metabolism in patients with borderline cerebrovascular reserve during intraoperative transient carotid occlusion

Sixty patients with borderline or frank insufficiency of their cerebrovascular reserve undergoing carotid endarterectomy were given enough short acting barbiturates, during cross clamping of the internal carotid artery, to cause EEG burst suppression. Arterial and venous concentrations of lactate were measured in blood samples taken before, 30 min after occlusion of the artery and 10 min after reperfusion. The amount of lactate produced depended on the length of time of burst suppression; the shorter it lasted, the larger the amount of lactate produced. Only in patients with the shortest burst suppression times did the blood lactate levels rise above normal levels. The lactate levels can be used as indicators of how effective barbiturates are being in preventing ischaemia during the time of carotid artery occlusion.

Cortical bone mineral content in primary hyperparathyroidism. Changes after parathyroidectomy

The bone mineral content (BMC) of 35 patients with primary hyperparathyroidism (PHPT) was measured at the mid radius (95% cortical bone) by photon absorptiometry of a 241Am source. The majority of the patients had an overt disease of moderate to severe degree. Average serum calcium of the group was 12.3 mg/100 ml (range 10.6 to 18.0 mg/100 ml). The percentage of normality of the BMC was (Av +/- 1 SD) 75.1 +/- 13.0% for the whole group. The average increment of BMC in 14 patients 9 to 26 months after parathyroidectomy was 9.9%, with a wide dispersion. However a highly significant negative correlation (r: 0.83; P less than 0.01) was found between the initial bone mass and the percentage increment per month after surgery. No further gain was observed 2 years after parathyroidectomy except in one patient with an extremely severe bone loss. In spite of the gain obtained after surgery the bone mass remained markedly diminished in most patients showing that the cortical bone loss caused by PHPT is mainly irreversible.

[Amniotic fluid embolism with coagulation disorder--a case report (author's transl)]

A case of amniotic fluid embolism during the delivery of a twin pregnancy is reported. After immediate resuscitation with artificial ventilation the mother and the neonates survived the acute episode. As a result of hyperfibrinolysis with premature separation of the placenta a dramatic postpartum haemorrhage occurred, which could be controlled by Fritsch' manoeuvre. Meanwhile it was possible to restore the coagulation disorder with fresh whole blood, fibrinogen and an antifibrinolytic agent (Aprotinin).

An unusual case of paroxysmal facial pain

Paroxysmal facial pain is a rare sequel to brainstem infarction. This is a report of a patient who developed paroxysmal facial pain with the exceptional features of a trigger zone and relative refractory pain-free periods in an area previously anesthetic after infarction of the brainstem. The characteristic of this patient's pain is compared with the pain is compared with the pain of trigeminal neuralgia and possible similar pathogenetic mechanisms.