The penetration of flucloxacillin into cortical and cancellous bone during arthroplasty of the knee

Antibiotic prophylaxis with 2 g flucloxacillin was given 2 h before operation in 23 adult patients undergoing knee replacement operations for rheumatoid arthritis or osteoarthrosis. The mean extracted concentration of flucloxacillin obtained at operation was 12.9 micrograms/ml (SD 5.25) in synovial fluid; 2.9 micrograms/g (SD 3.59) in synovium; 2.0 micrograms/g (SD 1.48) in cancellous bone and 1.3 micrograms/g (SD 1.25) in cortical bone. The minimum inhibiting concentration (MIC) value for flucloxacillin was usually 0.25 micrograms/g against Staphylococcus aureus. Therapeutically active concentrations were thus obtained. There were no adverse reactions from the antibiotic administration.

Cerebral blood-flow tomography: xenon-133 compared with isopropyl-amphetamine-iodine-123: concise communication

Tomographic maps of local cerebral blood flow (CBF) were obtained with xenon-133 and with isopropyl-amphetamine-iodine-123 (IMP) in 11 subjects: one normal, two tumor cases, and eight cerebrovascular cases. A highly sensitive four-face, rapidly rotating, single-photon emission tomograph was used. The Xe-133 flow maps are essentially based on the average Xe-133 concentration over the initial 2 min during and after an inhalation of the inert gas lasting 1 min. These maps agreed very well with the early IMP maps obtained over the initial 10 min following an i.v. bolus injection. The subsequent IMP tomograms showed a slight decrease in contrast amounting to appr. five percentage points in the CBF ratio between diseased and contralateral areas. It is concluded that Xe-133 is more practical: low cost, available on a 7-day basis, easily repeatable, quantifiable without the need for arterial sampling, and with low radiation exposure to patient and personnel. On the other hand, IMP gives an image of slightly higher resolution. It also introduces a new class of iodinated brain-seeking compounds allowing, perhaps, imaging of other functions more important than mere blood flow.

Clinical experience with azlocillin in the treatment of urinary tract infections with Pseudomonas aeruginosa

27 patients, aged 19-23 yr, with symptomatic urinary tract infection or epididymitis due to Pseudomonas aeruginosa were treated with azlocillin. All pseudomonas strains were sensitive to azlocillin. The microorganism was eradicated in 25/26 evaluable patients. 25/27 patients were clinically cured. Bacteriological relapse occurred in 11 patients. No serious drug reactions were noted.

Nutrition of the intervertebral disc: effect of fluid flow on solute transport

Adult dogs were injected intravenously with 35S-sulphate, and moderately exercised for one to six hours to measure isotope concentrations and profiles throughout the intervertebral discs. The isotope profiles were also observed in control animals that had been under anesthesia between injections and death. In both sets of animals, the profiles were in agreement with those expected for isotope transport by diffusion. This agreement indicates that fluid "pumping" during movement has an insignificant effect on transport of nutrients into the disc. Small solutes, e.g., O2, glucose, and sulphate, are transported into the disc chiefly by diffusion. However, calculations show that because of their low diffusivities, "pumping" may increase the rate of transport of large solutes into the disc, as it does in articular cartilage.

Carbohydrate metabolism and concentration profiles of solutes in the canine lumbar intervertebral disc

Utilization of glucose and oxygen by the cells as well as concentration profiles of solutes were studied in the canine intervertebral disc. Cell metabolism in this avascular tissue, being predominantly anaerobic, was found to be dependent on oxygen tension (this being especially pronounced in the region of 0.13-0.4 kPa (1-3 mmHg). A high production rate of lactic acid was found in the nucleus pulposus, whereas towards the periphery of the annulus fibrosus this rate gradually decreased. In the centrally located areas of the disc tissue, far away from the blood circulation, the highest concentrations of lactic acid were found. For the normal disc the energy demands seem to be met as even small amounts of oxygen account for a large energy source, whereas the cellular requirements are balanced up predominantly by glucose. In regions with extremely low oxygen tensions large amounts of glucose are consumed, but an additional potential energy pool of glycogen seems to be available.

Urine microscopy as screening method for bacteriuria

Fresh urine samples from 90 ambulatory patients with urological disorders were examined for leucocytes by counting the number of WBC/mm3 and per high power field (HPF) in sediment. Bacteria could be cultured in 20 samples, 18 of which contained greater than 8 WBC/mm3. Two (3%) of the 63 samples with less than or equal to 8 WBC/mm3 contained bacteria. Bacteriuria was found in two (3%) of 65 samples containing 0--1 WBC/HPF. Microscopic examination of the sediment might be used for the screening of patients with a high frequency and urgency of micturition for bacteriuria. A normal number of urinary leucocytes (less than or equal to 8/mm3) indicates that no bacteria will be found in culture. Leucocyturia indicates a high probability of bacteriuria.

Oxygen tension alterations in the intervertebral disc as a response to changes in the arterial blood

Measurements of oxygen tension in the canine lumbar intervertebral disc, by the use of a polarographic oxygen electrode, were performed. The oxygen tension in the arterial blood was changed by regulating the oxygen concentration in the inspired air. The alterations in oxygen tension in the nucleus pulposus, as a function of distance to the vertebral endplate were determined. The response times registered in the disc matrix were relatively short (within five min.), which implies an efficient solute transport from the vertebral blood pool underneath the hyaline cartilage into the avascular intervertebral disc.

Plasma proteins and anti-kidney antibodies in renal carcinoma

Occurrence of the nephrotic syndrome in association with renal carcinoma has been reported earlier. There is a risk of masking of carcinoma due to symptoms of nephrotic syndrome/glomerulonephritis. In this study the serum protein profile in patients with renal carcinoma was found to be similar to that of patients with glomerulonephritis. However, increased levels of complement factors C3 and C4 were found, indicating low or none complement consumption. Patients with metastasis had higher blood ESR, orosomucoid, CRP, C3 and C4 but lower Hb and albumin than patients without evidence of metastasis. Immunofluorescence examination of kidneys and sera indicated the occurrence of antibodies against glomerular structures, IgG antibodies were demonstrated in most patients, IgA and IgM in some.

Energy metabolism in relation to oxygen partial pressure in human skeletal muscle during exercise

1. The intramuscular oxygen partial pressure (pO2) in human gastrocnemius muscle was monitored during exercise and compared with metabolite concentrations reflecting the energy and the redox state in the tissue. Ten normal subjects and ten patients with peripheral vascular occlusive disease were investigated. 2. In normal subjects the pO2 at the end of exercise was related to the intensity of the exercise, expressed as effect (J/s) per contraction. 3. In both patients and normal subject the pO2 was related to the [ATP]/[ADP] ratio, the [lactate/[pyruvate] ratio and the phosphocreatine concentration in the muscle tissue at rest and during exercise. 4. At each pO2 value, a lower [lactate/[pyruvate] ratio was found in the muscle tissue of the patients compared with that of normal subjects. This was interpreted as a beneficial effect of the higher oxidative-enzyme capacity in the muscle of the patients. 5. The results show the importance of pO2 for the regulation of the energy and the redox state of the tissue. During exercise the changes induced in pO2 and thus the energy state will stimulate the respiratory rate. This might be an important link in triggering the oxidative-enzyme capacity in response to physical training as well as in peripheral vascular occlusive disease.

Exposure to acetone. Uptake and elimination in man

Eight male subjects were exposed to acetone vapor on two occasions for 2 h in the laboratory. On the first occasion they were exposed to about 1,300 mg/m3 during rest and on the second occasion to about 700 mg/m3 during rest (30 min) and exercise at different work loads on a bicycle ergometer (90 min). The total uptake of acetone was 0.6--1.2 g, and the relative uptake was about 45%. The concentration of acetone in alveolar air was 30--40% of that in the inspiratory air, and it was not affected by exposure time or work load. The concentration of acetone in blood increased continuously with increased uptake during exposure, and there was no tendency towards equilibrium. The half-time of acetone in alveolar air as about 4 h, and in venous and arterial blood it was about 6 and 4 h, respectively. The highest concentrations of acetone in urine were measured 3--3.5 h after exposure. The elimination of acetone via the lungs corresponded to about 20% of the total uptake. Only about 1% of the uptake was excreted via urine.

Nutrition of the intervertebral disc: solute transport and metabolism

The metabolism of the canine nucleus pulposus was investigated at different oxygen tensions. It was found that even at high oxygen tensions the metabolism is mainly anaerobic, only approximately 1.5% of the glucose being converted to carbon dioxide. The concentration dependence of oxygen consumption is limited to very low oxygen tensions. Values of oxygen consumption and lactic acid production were used to calculate the concentration profiles of these substances within the nucleus pulposus, using a diffusion theory. The predicted concentration profiles were compared with the experimental measurements of concentration at various positions in the disc. The good agreement in these values found in the nucleus confirms that the main mechanism of metabolite transport is diffusion, and the main route of nutrient supply into the nucleus is via the endplate.

Breath concentration as an index of the health risk from benzene. Studies on the accumulation and clearance of inhaled benzene

Human subjects were exposed to known concentrations of benzene in air for single and repeated daily periods. The breath concentrations measured repeated exposures approached a maximum after 3 d, and this phenomenon indicated that the tissues were approaching saturation under the experimental conditions. The breath concentrations measured after exposure indicated an initial rapid clearance of benzene with a half-time of 2.6 h, followed by a slower phase with a half-time of 24 h. The decay in breath concentration after prolonged occupational exposure appeared to be slower; the difference between the laboratory and industrial studies was, however, not significant. The hygienic significance of these results was discussed, and it was recommended that control measures be employed when a morning breath concentration exceeds 10 ppb.

Cefuroxime treatment of urethritis caused by a beta-lactamase-producing strain of Neisseria gonorrhoeae

A patient who contracted urethritis from a beta-lactamase-producing strain of Neisseria gonorrhoeae was successfully treated with the cephalosporin derivative cefuroxime. As expected, neither cefuroxime nor cefamandole was hydrolysed by plasmid-coded gonococcal beta-lactamase. Cefuroxime ought to be a valuable and efficacious substitute for penicillins in the treatment of gonhorrhoea due to beta-lactamase-producing gonococcal strains.

The role of the synovial fluid and tendon sheath for flexor tendon nutrition. An experimental tracer study on diffusional pathways in dogs

Radioactive tracers were used to analyse nutritional mechanisms of flexor tendons of dogs during various experimental conditions. The transport and distribution of methyl glucose in the tendon was analysed 15 min after intravenous injection during the following experimental conditions: (1) normal state--rest; (2) passive mobilization of the tendon; (3) active mobilization of the tendon; (4) exclusion of exposure to synovial fluid-preservation of vascular supply; (5) exclusion of vascular supply--preservation of exposure to synovial fluid. The results indicate that active mobilization gives a significant increase in tracer concentration in the volar part of the tendon, while passive mobilization has no such effect. Diffusional pathways from the synovial fluid plays a major role for transport of tracer into the tendon, while the intrinsic vascular system apparently is of no or minor importance in this respect. The main mechanism for solute transport within the tendon is passive diffusion. Transport of sulphate in the volar part follows a similar pattern as in other avascular tissues and the incorporation of sulphate by the cells is low and comparable to that in articular cartilage. The results support our previous hypothesis that the flexor tendon system physiologically corresponds to a joint, and that the synovial fluid plays an important role for flexor tendon nutrition.

[Caudal anaesthesia in obstetrics (author's transl)]

The advantages of caudal anaesthesia in obstetrics far outweigh the few disadvantages. The perinatal mortality of premature infants is reduced under caudal anaesthesia. Breech deliveries are easier under caudal anaesthesia. In these cases regional anaesthesia is considered an obstetrical indication. It is possible to carry out all vaginal and abdominal procedures with this anaesthesia. The elimination of pain during labor and delivery permits a more intensive experience of labor and delivery for the mother under caudal anaesthesia.

Effects of low ampicillin concentrations on penicillin sensitive and beta-lactamase producing strains of Neisseria gonorrhoeae

The effects of therapeutic concentrations of ampicillin on non-beta-lactamase and beta-lactamase producing strains of Neisseria gonorrhoeae were studied. A small but significant fraction of bacteria in a gonococcal population was found to respond in a bacteriostatic rather than a bactericidal way upon ampicillin treatment. In agreement with this was the finding of morphologically unaltered cells in the scanning electron microscope after ampicillin exposure. Ampicillin treatment of beta-lactamase producing gonococci caused a significant release of the enzyme into the surrounding growth media. However, initially all beta-lactamase activity was cellbound. The rate of initial ampicillin hydrolysis was much higher in intact cells of N. gonorrhoeae (TEM-1) than in cells of Escherichia coli K-12 (TEM-1). This suggests that the diffusion rate of ampicillin is much higher in the former organism. The viability of gonococci (TEM-1) was unlike E. coli (TEM-1) affected by low concentrations of ampicillin. However, after complete hydrolysis of ampicillin, viable gonococci (probably bacteriostatic reacting cells) were able to initiate new growth. This heterogeneity of the cell population to penicillin killing is probably one reason why beta-lactamase producing gonococci despite a rather low MIC-value to ampicillin cause infections that are not susceptible to therapy by this agent.

The use of co-trimazine and co-trimoxazole in elderly patients with urinary tract infections

In a double-blind study geriatric patients received either 410 mg sulphadiazine plus 90 mg trimethoprim (co-trimazine) or 800 mg sulphamethoxazole plus 160 mg trimethoprim (co-trimoxazole) twice daily. The investigation was carried out in order to compare the clinical efficacy and safety of co-trimazine in relation to co-trimoxazole with special emphasis on laboratory data in elderly patients suffering from uncomplicated urinary tract infections. Two to four weeks after start of treatment the original pathogen was eradicated in 80% of the 40 patients that were assessable for the effect of co-trimazine therapy, and in 77.8% of the 39 assessable patients in the co-trimoxazole group. There were no statistically significant differences between the two treatment groups in terms of laboratory data. Both drugs were well tolerated.

Reaction to cold of patients with coronary insufficiency

Twenty six patients with angina pectoris and coronary insufficiency as judged by an exercise ECG test were examined. About half of the patients had more pronounced ECG changes in a cold room at -15 degrees C than at room temperature. They worked less, their subjective rating of exertion during exercise was higher and the heart performed less work, expressed as the heart rate blood pressure product. The other half of the patients was not much influenced by cold. During an exercise test in the supine position almost all patients got more pronounced ECG changes, worked less and the heart performed less work than in the sitting position. It is suggested that cold exposure as well as a supine body position may to a considerable part exert their effect, i.e. lower the anginal threshold and increase ECG changes, by increasing the central blood volume and the diastolic volume of the left heart and thus ceteres paribus the myocardial oxygen consumption.

Oxygen tension measurements in the intervertebral disc. A methodological and experimental study

A polarographic membrane-covered electrode has been used for measurements of oxygen tension in the intervertebral disc. In vitro studies showed that the method measured partial pressures of oxygen with good reproducibility. However, in long continuous experiments, disc matrix adhering to the membrane influenced the readings negatively. The results of in vivo measurements in canine nucleus pulposus showed tensions of the order of 0.53 - 1.06 KPa (4 - 8 mm Hg). No significant variations between different disc levels were found.

Biological threshold limits for benzene based on pharmacokinetics of inhaled benzene in man

Volunteers were exposed to benzene, 2--10 ppm, under controlled conditions up to 6 h a day during five consecutive days. The accumulation and elimination of benzene was measured by determination of benzene concentration -- down to 0.001 ppm -- in exhaled breath. From these observations, a multicompartment model, which approximately describes the kinetics of benzene elimination and accumulation has been designed. On the basis of this model, benzene concentrations in breath, corresponding to exposure levels of benzene, have been estimated. Thus, at a daily exposure to 10 ppm the exhaled benzene concentration in the morning after a day of exposure will not exceed 0.1 ppm.