Experimental telemedicine in orthopaedics

An accurate technique that simplifies measurements of two- and three-dimensional specimens is presented. Photomicrographs of a microruler and of the specimens of a research project were made at the same magnification. A ruler with the exact dimensions of the photographic prints of the microruler was generated through computer graphics and printed as a transparency. After verification, the ruler was used to measure specimens directly on the photomicrographs.     

Chronic ulcers and antibiotic treatment

This study analysed 656 wound samples from patients with chronic wounds in order to determine the bacterial flora and patterns of antibiotic use and resistance. Almost all wounds (95.1%) were colonised with at least one bacterial species; 26% of all patients were on antibiotic treatment. The total number of bacterial isolates resistant to antibiotics was low.     

125I-labelling of an internally 75Se-labelled monoclonal antibody--biodistribution in tumour-bearing nude mice

A monoclonal antibody, C215, was first internally labelled with 75Se-methionine and then labelled with 125I. The biodistribution of the dual-labelled [125I][75Se]C215 was studied in tumour-bearing nude mice killed 3 days after injection. The biodistribution of the dual-labelled [125I][75Se]C215 was compared with the biodistribution of single-labelled [131I]C215 and [75Se]C215. Iodine-labelled antibodies seem to be damaged during iodination, affecting the disappearance rate and tumour uptake. There were no signs of dehalogenation of circulating antibodies or antibodies taken up in the tumour.     

Main results of the losartan versus amlodipine (LOA) study on drug tolerability and psychological general well-being. LOA Study Group

OBJECTIVE: To compare two losartan regimens (with and without hydrochlorothiazide) and amlodipine in treating mild-to-moderate hypertension regarding their blood-pressure-lowering effect, drug tolerability and quality of life. DESIGN: A 12-week, randomized, double-blind, parallel-group, multi-centre study. After 4 weeks of placebo, patients with a diastolic blood pressure (DBP) in the range 95-115 mmHg were allocated randomly to be administered 50 mg losartan (increased to 100 mg if the DBP was 90 mmHg or more after 6 weeks), 50 mg losartan (plus 12.5 mg hydrochlorothiazide under the above conditions), or 5 mg amlodipine (increased to 10 mg under the above condition). The tolerability of the treatment and the quality of life were evaluated by spontaneous reporting, active questioning and the Psychological General Well-Being (PGWB) index. STUDY POPULATION: In total 898 hypertensives, mainly referred from primary health care (mean age 57.8 years) of whom 52% were men. RESULTS: Administration of 50 mg losartan (plus 12.5 hydrochlorothiazide if necessary) and of 5 mg amlodipine (or 10 mg if necessary) lowered the blood pressure as well as or better than did 50 mg losartan (or 100 mg if necessary). The incidence of 'any discomfort' and 'swollen ankles' increased with amlodipine but not with losartan treatment. The opposite was found for 'dizziness upon standing'. The incidence of drug-related adverse events and the number of patients withdrawn from therapy were higher with amlodipine than they were with losartan treatment. The PGWB index at week 12 indicated that improvements from baseline had occurred in some domains for the losartan groups whereas it remained unchanged for the amlodipine group. CONCLUSION: Both losartan and amlodipine were effective in lowering the blood pressure and were tolerated well. Administration of 50 mg losartan (plus 12.5 mg hydrochlorothiazide if necessary) and of 5 mg amlodipine (or 10 mg if necessary) lowered the blood pressure equally well or better than did 50 mg losartan (or 100 mg if necessary). Drug-related adverse effects and withdrawal from the study were more common for the amlodipine group. The clinical significance of the improvements in the PGWB index with losartan needs to be studied further.     

Inflammation as a cause of malnutrition, atherosclerotic cardiovascular disease, and poor outcome in hemodialysis patients

Cardiovascular disease (CVD) remains the major cause of morbidity and mortality in end‐stage renal disease (ESRD) patients treated by hemodialysis (HD). Although traditional risk factors are common in dialysis patients, they may not alone be sufficient to account for the unacceptable high prevalence of CVD in this patient group. Recent evidence demonstrates that chronic inflammation, a nontraditional risk factor that is commonly observed in HD patients, may cause malnutrition and progressive atherosclerotic CVD by several pathogenetic mechanisms. The cause(s) of inflammation in HD patients is multifactorial and includes both dialysis‐related (such as graft and fistula infections, bioincompatibility, impure dialysate, and back‐filtration) and dialysis‐unrelated factors. Although inflammation may reflect underlying CVD, an acute‐phase reaction may also be a direct cause of vascular injury. Available data suggest that proinflammatory cytokines play a central role in the genesis of both malnutrition and CVD in ESRD. Thus, it could be speculated that suppression of the vicious cycle of malnutrition, inflammation, and atherosclerosis (MIA syndrome) would improve survival in dialysis patients. As there is not yet any recognized, or even proposed, targeted treatment for ESRD patients with chronic inflammation; it would be of considerable interest to study the long‐term effect of various anti‐inflammatory treatment strategies on nutritional and cardiovascular status as well as outcome in these patients.     

Survival of Lubinus straight (IP) and curved (SP) total hip prostheses in 543 patients after 4-13 years

The clinical outcome and survival of 543 total hip arthroplasties with Lubinus cemented total hip prostheses after a mean of 7.9 years are reported. Clinical evaluation revealed no significant differences between patients with a straight stem and those with a curved anatomic stem. Loosening was statistically associated with young age, male sex, heavy weight, diagnosis other than osteoarthritis and year of operation. Survivorship analysis of the Lubinus IP implant at 8 years revealed a 95% chance of survival. The survival of the SP implant was 96%. After this time point the curve for SP implants began to fall at a faster rate than that for IP implants.     

Increased peritoneal permeability is associated with decreased fluid and small-solute removal and higher mortality in CAPD patients

BACKGROUND: Recent studies suggest that increased peritoneal membrane permeability is associated with higher morbidity and mortality in peritoneal dialysis patients. It is not known, however, whether the difference in clinical outcome among different peritoneal transport groups is due to differences in peritoneal fluid and solute removal. In the present study, we compared the peritoneal fluid and solute transport and clinical outcome in CAPD patients with high (H), high-average (H-A), low-average (L-A) and low (L) peritoneal transport patterns. DESIGN: A 6-h dwell study was performed in 46 patients with frequent dialysate and plasma samples using 2 l of 3.86% glucose dialysate with 131I albumin as an intraperitoneal volume marker. The patients were divided into four transport groups according to their D/P of creatinine at 240 min. RESULTS: The results showed that high transporters had significantly lower peritoneal fluid and small-solute removal but high glucose absorption and high protein loss during a 6-h exchange. The serum albumin was lower and blood pressure and triglycerides were higher in high transporters compared with the other groups. Two-year patient survival from the start of CAPD treatment was significantly lower for high transporters (64, 85, 90 and 100% for H, H-A, L-A and L respectively, P < 0.01). The 1-year patient survival from the dwell study was also significantly lower in high transporters (16, 63, 90 and 100% for each group, P<0.01). CONCLUSION: Our results suggest that high transporters remove less fluid and small solutes and have higher protein loss and increased glucose absorption. These alterations may contribute to fluid overload, malnutrition and lipid abnormalities that perhaps contribute to the increased mortality among the high transporters.     

Two-phase flow in a full-scale loop seal facility

An experimental program has been carried out to study two-phase behaviour of a PWR cold leg loop seal during loss-of-coolant accidents. The experimental facility comprises a full-scale cold leg with a reactor coolant pump simulator. Three separate air/water test series were performed to determine the onset of slugging in the horizontal pipe, the residual water mass and the total two-phase pressure drop in the loop seal.The results of flow regime transition experiments have been compared with smaller-scale experiments and with theoretical predictions to evaluate scaling criteria. The strong hysteresis of transitions found between the stratified and slug flow regimes depends on the loop seal geometry and U-tube oscillations.     

Brain-derived neurotrophic factor promotes the differentiation of various hippocampal nonpyramidal neurons, including Cajal-Retzius cells, in organotypic slice cultures

Brain-derived neurotrophic factor (BDNF) is widely expressed in the central nervous system, where its function is poorly understood. The aim of this study was to investigate the effects of BDNF on the differentiation of hippocampal nonpyramidal neurons using organotypic slice cultures prepared from postnatal rats. The application of BDNF induced an increase in immunostaining for the microtubule-associated protein (MAP)-2 in non-pyramidal neurons of the stratum oriens. BDNF promotes the elongation of the dendrites of these neurons, as demonstrated by analysis after biocytin labeling. Calbindin-D- and calretinin-containing subgroups of nonpyramidal cells in the stratum oriens were responsive to BDNF but not to nerve growth factor, as shown by an increase in the number of neurons immunostained for these proteins. BDNF also induced an increase in neuropeptide Y immunostaining of stratum oriens neurons. In contrast, BDNF had no effect on parvalbumin immunostaining, despite the fact that these cells express the BDNF receptor trkB. In addition, BDNF increased calretinin immunoreactivity in Cajal-Retzius cells situated around the hippocampal fissure. The Cajal-Retzius neurons persisted in slices beyond the time at which they degenerate in vivo. However, BDNF is not required for the survival of these cells, because they also persisted in slices from BDNF knock-out mice. The present results indicate that BDNF exerts an effect on the morphology of stratum oriens nonpyramidal cells and their calcium-binding protein levels. BDNF also regulates the calretinin content of Cajal-Retzius cells but is not necessary for their survival.