Valgus knee injuries: evaluation and documentation using a simple technique of stress radiography

Clinical assessment of post traumatic ligament laxity is subjective. Stress radiographs provide an objective and permanent record of the laxity. We describe a simple method of stress radiography to help evaluate and to document valgus knee injuries. In this study we have correlated the X-ray findings with those at arthroscopy. No specialised equipment is required and radiation exposure to the patient and the surgeon is minimal. With the patient under general anaesthesia the injured and the normal knee are firmly bound together. A valgus stress is applied to both the knees simultaneously and a radiograph is taken. The opening of the medial joint space is measured as in the figure 1, i.e. the perpendicular distance between the tangent drawn to the subchondral bone of the femoral condyles, and the most medial point of the tibial plateau. The opening of the medial joint space provides a direct measure of valgus laxity. The ratio of the medial joint opening to the normal knee is calculated. A ratio of two or more is indicative of an associated anterior or posterior cruciate ligament rupture in addition to medial collateral ligament injury.     

A clinical method for locating the femoral head centre during total knee arthroplasty

Localisation of the femoral head centre (FHC) during total knee arthroplasty (TKA) is necessary when assessing the overall alignment of the leg using an extramedullary guide for the femur. On-table radiographs for this purpose are time consuming and inconvenient. We describe a clinical method for estimating the FHC: it is marked 1.5 cm lateral to the point where the femoral artery crosses the line joining the pubic tubercle and the anterior superior iliac spine. Using this method the estimated FHC was within 15 mm of the anatomic centre in 84% of cases, and within 24 mm in 99%. This translates into possible knee alignment errors of 2 degrees and 3 degrees, respectively. As alignment error of up to +/-3 degrees is compatible with satisfactory clinical results of TKA, our method provides useful approximation of the FHC. For greater accuracy however, an on-table radiograph is recommended.     

Ethanol-Induced Stimulation of Hepatic Ornithine Decarboxylase Activity in the Rat

The effect of a single feeding of ethanol on hepatic ornithine decarboxylase (ODC) activity in rats was investigated. Ethanol (7.5 g/kg body weight) was tube-fed to overnight-fasted rats as a 50% (v/v) solution in water 1, 2, 3, 4, 8, 12, or 24 hr before sacrifice. The levels of ODC activity in the livers were assayed in vitro by measuring the release of ¹⁴C0₂ from 0L-1-¹⁴C-ornithine. Hepatic ODC activities were significantly stimulated by ethanol (7.5 g/kg body weight) beginning at 1 hr and reaching a peak at 4 hr (more than a 16-fold increase over zero time controls). Single feedings of varying doses of ethanol (2.5, 5.0, or 7.5 g/kg body weight) to overnight-fasted rats 3 hr before sacrifice also exhibited significant increases (3 to 13-fold) in the hepatic ODC activities. In vitro ¹⁴C-leucir>e incorporation into protein using hepatic microsomes of ethanol-treated rats was decreased in comparison with that of controls. The ethanoMnduced stimulation of hepatic ODC activity was not abolished by pretreatment with pyrazoie, an inhibitor of ethanol metabolism. However, the stimulation of hepatic ODC activity by ethanol was suppressed by actinomycin D or cycloheximide, indicating that the enhancement is attributable to the synthesis of new enzyme protein. Furthermore, abolition of the stimulation of hepatic ODC activity due to ethanol by prior adrenalectomy suggests that the induced increase is probably mediated through stimulation of adrenal hormones. These studies demonstrate that a single dose of ethanol per os can significantly enhance in the rat the activity of hepatic ODC, a key enzyyme in the biosynthesis of polyamines, and that the effect is indirect, via adrenal hormones.     

One-Year Follow-up of Duodenal Ulcers after 1-Wk Triple Therapy for Helicobacter pylori

Objective : to study the ulcer recurrence rate of Helicobacter pylori-positive duodenal ulcers at 1 yr after eradication of the bacteria by triple therapy. Method : Patients with H. pylori-positive duodenal ulcers were randomized to receive either triple therapy for 1 wk plus omeprazole for 4 wk (THple+OMP) (n = 78), or omeprazole alone (OMP) for 4 wk (N = 77). Patients were followed up every 3 months for symptom enquiry. At 1 yr, all asymptomatic patients were invited to attend for gastroscopy. Results : At 8 wk, 16 patients in the OMP group and four in the Triple+OMP group had an ulcer. During the 1-yr period, 12 patients in the OMP group and no patient in the Triple+OMP group developed symptomatic ulcers. At follow-up endoscopy at 1 yr, another 10 ulcers were detected in the OMP group and two in the Triple+OMP group. Fifteen patients in the OMP group and 13 in the Triple+OMP group were lost to follow-up. In total, ulcers were de-tected in 39 of 61 (64%) assessahle patients in the OMP group, and in six of 65 (97o) assessahle patients in the Triple+OMP group after I yr (χ² test: p < 0.001). Of the patients whose H, pytori were successfully eradicated hy Triple+OMP at 8 wk, 90% remained H. pylori negative at 1 yr. Conclusion : Triple therapy for 1 wk eradicates H, pylori infection and significantly reduces duodenal ulcer relapses.     

Effect of covalently bound fatty acids and associated lipids on the viscosity of gastric mucus glycoprotein in cystic fibrosis

The contribution of associated and covalently bound lipids to the viscosity of gastric mucus glycoprotein in healthy and cystic fibrosis (CF) individuals was investigated. While both preparations exhibited similar contents of protein and carbohydrate, the CF glycoprotein contained 1.3 times more associated lipids and 6 times more covalently bound fatty acids. The viscosity of CF mucus glycoprotein was about 1.8 times higher than that of normal glycoprotein. Extraction of associated lipids lead to 3-fold drop in the viscosity of CF glycoprotein and 5-fold drop in the case of normal glycoprotein. Removal of covalently bound fatty acids caused further 1.6-fold reduction in the viscosity of normal mucus glycoprotein and 6-fold in CF glycoprotein. The viscosity of the delipidated and deacylated CF mucus glycoprotein was only about 10% higher than that of the similarly treated normal glycoprotein. The results suggest that the elevated level of covalently bound and associated lipids is responsible for the increased viscosity of CF mucin.     

Effect of tryptophan on the inhibitory action of selected hepatotoxic agents on hepatic protein synthesis

Tryptophan has been demonstrated earlier to induce a rapid stimulation of polyribosomal aggregation and protein synthesis in the livers of rats and mice. Also, tryptophan has been reported to have a corrective effect upon hepatic polyribosomes and protein synthesis when administered in conjunction with some hepatotoxic agents which inhibit protein synthesis by a variety of different mechanisms. This investigation expands the information in regard to whether the inhibitory effects on protein synthesis by a variety of hepatotoxic agents may be ameliorated by tryptophan administration and determines whether tryptophan may act to prevent, to cure, or both in regard to the inhibitory effect of each of the toxic agents. Under the short-term experiments conducted in this study, tryptophan was found to act in a preventive and curative manner with α-amanitin, cordycepin, puromycin, and hypertonic NaCl; only preventive with CCl₄ and NaF; only curative with actinomycin D and ethionine; and neither with sparsomycin. Experiments were conducted to determine whether hepatic mRNA synthesis and nucleocytoplasmic translocation of RNA were affected by tryptophan in rats after treatment with selected hepatotoxic agents and the results revealed, in general, that the effects due to tryptophan occurred only when tryptophan acted in a curative manner. In a few experiments, tryptophan-related compounds, 5-hydroxy-dl-tryptophan, 5-fluorotryptophan, 3-hydroxyanthranilic acid, and indole, were tested, using equimolar amounts to l-tryptophan, with some hepatotoxic agents and in general, they caused some improvement in hepatic polyribosomal aggregation and protein synthesis but usually much less than with l-tryptophan.     

Problems of Psychological Monitoring in Astronaut Training

在进行职业训练时，对受训者的心理变化趋势进行监视是必要的。航天员心理因素的发展水平可通过心理测试来检测，以便能对其重要的心理指标进行评价，并给出综合评价。文中列出应进行测试的心理指标，并根据大量的样本统计给出了经验加权因子。测试结果的积累可以预测航天员将来飞行任务中处理复杂问题的能力，并能帮助改进训练过程及暴露缺点。