The relative bioavailability of metoprolol following oral and rectal administration to volunteers and patients

The pharmacokinetics, efficacy and safety of metoprolol tartrate 25 mg fatty suppositories were studied in 5 healthy volunteers and in 8 patients suffering from instable angina pectoris. Metoprolol 25 mg capsules were used as a control oral dosage form. Metoprolol showed a considerable rectal bioavailability (AUC, C max) and was absorbed quickly from the rectum (T max). In both groups rectal bioavailability was comparable. However, oral bioavailability was much lower in the volunteer group than in the patient group. Furthermore, ratios of metoprolol/aOHmetoprolol concentrations in plasma and urine gave an indication for a partial avoidance of the first pass effect after rectal administration. Further research is necessary to define an exact rectal dosage of metoprolol. In all patients, a substantial drop in heart rate, systolic and diastolic blood pressure was seen after administration of the first suppository. Metoprolol suppositories appear to be an effective, safe and suitable alternative for patients who are in need for beta blocking medication and who are unable to take oral medication for a certain amount of time.     

Patient position reproducibility in fractionated stereotactic radiotherapy: an update after changing dental impression material.

The reproducibility of patient positioning within the Gill-Thomas-Cosman relocatable stereotactic frame was re-evaluated following the substitution of a new, softer, dental impression material for the original hard acrylic compound. The average total displacement for a series of 10 patients was 1.1 mm (+/- 0.6 mm). Rotational discrepancies were small. This technique cannot deliver accurate repositioning in the absence of patient co-operation.     

Hepatic scintigraphy in management of infants and children with liver disease

Scintiscans of liver and spleen using technetium 99m sulphur colloid in 15 infants with extrahepatic biliary atresia and 11 infants with severe obstructive jaundice (7 with genetic deficiency of alpha 1-antitrypsin) showed similar hepatic size, pattern of isotope uptake, and splenic abnormality with no distinguishing features. In 37 older children with a variety of liver disorders, the scan was invaluable in showing filling defects in five instances. Selenomethionine was taken up not only by the two filling defects due to hepatoblastoma but also in a haemangioendothelioma. In the remaining patiens liver scanning confirmed hepatic abnormality and the necessity for more specific invasive diagnostic investigations.     

Perceptual matching in patients with cerebral lesions

Tasks of perceptual matching, including three types of visual stimulus (slope of line, position of dot and size of gap in contour) were devised. Seventy-four patients with unilateral cortical lesions were tested. The right parietal group was impaired on the perceptual matching tasks. There was no association between performance on perceptual matching tasks and tachistoscopic threshold measurements or a test of picture recognition. The relationship between perceptual matching and performance on other more complex visual tasks is discussed.     

Different effects of L-histidinol and homoharringtonine on 5-fluorouracil and bis-chloroethylnitrosourea activity in a murine model.

A comparison of the effects of L-histidinol and homoharringtonine (HHT) on the activity of 5-fluorouracil (FUra) and bis-chloroehtylnitrosourea (BCNU) in C57/BL mice, without or with disseminated B16f10 melanoma, was carried out. Although L-histidinol and HHT are both protein synthesis inhibitors with apparently identical modes of action, these two compounds had very different effects in the test systems. HHT failed to prevent the body weight lose and subsequent death of C57/BL mice treated with supralethal doses of FUra; it was also unable to prevent the toxicity of FUra for bone marrow cells. In contrast, L-histidinol prevented the weight loss, death and bone marrow damage otherwise resulting from identical doses of FUra. Furthermore, L-histidinol was far more effective than HHT in its ability to improve the management of disseminated B16f10 melanoma in C57/BL mice by BCNU, both in terms of reducing pulmonary foci and extending survival.     

SEAT-BELT SYNDROME REVISITED

This report describes a complex syndrome of injuries occurring in a young female who was a back seat passenger wearing a lap-belt restraint in a high-speed road traffic accident. As a consequence of the forced flexion distraction injury of her lumbar spine, she sustained a fracture-subluxation of the first lumbar vertebra in association with a jejunal perforation and extensive small intestinal mesenteric laceration. She also had a large traumatic hernia of the anterior abdominal wall, which was overlooked at primary laparotomy. This report highlights collectively the classical combination of injuries associated with the lap-belt syndrome and demonstrates the importance of carefully inspecting the anterior abdominal wall for deficiencies, because traumatic herniation may be easily overlooked.     

维生素E和冠心病

有各种不同的研究评价过维生素E(VitE)的抗氧化作用在冠心病预防及治疗中的意义.体外研究提示VitE保护LDL,使之不被氧化,减少血管壁上致粥样硬化的oxLDL的沉积.