Qualitative study of antibiotic prescription patterns and associated drivers in Sudan, Guinea-Bissau, Central African Republic and Democratic Republic of Congo

OBJECTIVES

The objective of this study was to address the knowledge gap regarding antibiotic use in Medecins Sans Frontiéres (MSF) projects located in Africa by exploring antibiotic prescription and consumption habits and their drivers at different healthcare levels.

DESIGN

This study used an exploratory study design through thematic analysis of semistructured, in-depth interviews, focus group discussions (FGDs) and field observations in order to understand the main drivers influencing current antibiotics prescription habits and consumption habits of patients in different geographical settings.

SETTING

The study took place in MSF centres and towns across four countries: Guinea-Bissau, Central African Republic (CAR), Democratic Republic of Congo (DRC) and Sudan.

PARTICIPANTS

384 respondents participated in the study, which includes project staff, prescribers, community members, patients, among other groups.

RESULTS

Treatment protocols were physically present in all countries except DRC, but compliance to protocols varied across contexts. A failing health system and barriers to accessing healthcare were perceived as major drivers of overuse and inconsistent prescription practices. Patient demands influenced prescription decisions, and self-medication was commonly reported in the context of failing health systems. Additionally, there was a strong demand for quick cures and communities preferred injections over pills. Patients tended to stop antibiotic treatment once symptoms abated and had major gaps in understanding antibiotic intake instructions and functions.

CONCLUSIONS

While there were specific findings in each context, the larger trend from these four MSF projects in Africa indicates widespread use of antibiotics based on unclear assumptions, which are often influenced by patient demands. There needs to be a broader focus on the balance between access and excess, especially in such fragile contexts where access to healthcare is a real challenge.

Regulation of electrolyte and fluid metabolism in multi-stage ultra-marathoners

The purposes of this study were (i) to determine the prevalence of exercise-associated hyponatremia (EAH) in multi-stage ultra-marathoners and (ii) to gain more insight into fluid and electrolyte regulation during a multi-stage race. Body mass, sodium concentration ([Na⁺]), potassium concentration ([K⁺]), creatinine, urea, specific gravity, and osmolality in urine were measured in 25 male ultra-marathoners in the 'Swiss Jura Marathon' 2008 with 11,000 m gain of altitude over 7 stages covering 350 km, before and after each stage. Haemoglobin, haematocrit, creatinine, urea, [Na⁺], [K⁺], and osmolality were measured in plasma before stage 1 and after stages 1, 3, 5, and 7. Two athletes (8%) showed plasma [Na⁺] <135 mmol/l. Body mass, plasma [Na⁺], and plasma [K⁺] remained unchanged (p>0.05). Urine specific gravity (p<0.001) and osmolality in both plasma (p<0.01) and urine (p<0.001) were increased and haematocrit (p<0.0001), haemoglobin (p<0.0001) and plasma albumin were decreased (p<0.001). Plasma volume (p<0.01) and plasma urea (p<0.001) were increased. The K⁺/Na⁺ ratio in urine increased >1.0 after each stage and returned to <1.0 the morning of the next stage (p<0.001). To summarize, more sodium than potassium was excreted during rest. The increased urinary sodium losses during rest are compatible with the syndrome of inappropriate secretion of antidiuretic hormone (SIADH) or the cerebral salt-wasting syndrome (CSWS). Further studies are needed to determine the antidiuretic hormone (ADH) and both the atrial natriuretic peptide (ANP) and the brain natriuretic peptide (BNP) during multi-stage races.

Effect of a multistage ultraendurance triathlon on aldosterone, vasopressin, extracellular water and urine electrolytes

Prolonged endurance exercise over several days induces increase in extracellular water (ECW). We aimed to investigate an association between the increase in ECW and the change in aldosterone and vasopressin in a multistage ultraendurance triathlon, the 'World Challenge Deca Iron Triathlon' with 10 Ironman triathlons within 10 days. Before and after each Ironman, body mass, ECW, urinary [Na(+)], urinary [K(+)], urinary specific gravity, urinary osmolality and aldosterone and vasopressin in plasma were measured. The 11 finishers completed the total distance of 38 km swimming, 1800 km cycling and 422 km running within 145.5 (18.8) hours and 25 (22) minutes. ECW increased by 0.9 (1.1) L from 14.6 (1.5) L prerace to 15.5 (1.9) L postrace (P < 0.0001). Aldosterone increased from 70.8 (104.5) pg/mL to 102.6 (104.6) pg/mL (P = 0.033); vasopressin remained unchanged. The increase in ECW was related neither to postrace aldosterone nor to postrace vasopressin. In conclusion, ECW and aldosterone increased after this multistage ultraendurance triathlon, but vasopressin did not. The increase in ECW and the increase in aldosterone were not associated.

Swimming in ice cold water

INTRODUCTION

We investigated two athletes swimming in 4°C for 23 min (1.3 km, swimmer 1) and 42 min (2.2 km, swimmer 2), respectively.

MATERIALS AND METHODS

Pre swim, percent body fat was determined; post swim, core temperature was measured.

RESULTS

The core temperature of swimmer 2 was: 37.0°C immediately before the start, 32°C 20 min after getting out of the water, and 35.5°C 80 min after finishing the swim.

CONCLUSION

We assume that the higher skin-fold thickness and body fat of swimmer 2 enabled him to perform longer. In addition to this, mental power and experience in cold water swimming must be considered. In any athlete aiming at swimming in water of less than 5°C, body core temperature and heart rate should be continuously monitored in order to detect a body core temperature below 32°C and arrhythmia to pull the athlete out of the water before life-threatening circumstances occur.

[Change of body composition in an 81 year old runner in a 100 km run]

An 81-year-old runner completed successfully a 100-km-run within 19 h 45 min one year after coronary artery bypass surgery in recently diagnosed atherosclerotic coronary heart disease. Prior and shortly after the run, percent body fat, lean body mass, skeletal muscle mass and percent body water were determined non invasively both by the bioelectrical impedance analysis (BIA) and the traditional anthropometrical method. In addition, blood and urine samples were collected in order to evaluate fluid homeostasis. Proton nuclear magnetic resonance ((1)H-NMR) spectroscopy of the urine was performed in order to detect changes in metabolites of carbohydrate, fat and protein metabolism. Body mass increased by 1.9 kg, calculated skeletal muscle mass increased by 0.1 kg, calculated fat mass from anthropometric method decreased by 0.2 kg and from BIA by 3.1 kg. Calculated body water from BIA increased by 1.2 l and plasma volume decreased by 19%. Haematocrit, nitrogen urea, urinary specific gravity decreased whilst sodium increased. (1)H-NMR spectroscopy revealed an increase of ketone bodies after the run. To demonstrate a decrease of skeletal muscle mass after a 100-km-run, we should wait with the measurements of body masses until body water has reached pre race value. The increase of body water is unclear. In future studies, additional methods should be performed to provide information whether skeletal muscle mass decreased after endurance performance and whether metabolites of skeletal muscle mass degradation may impair renal function.

[The effect of a multi-stage ultra-endurance triathlon over ten times an iron-man-triathlon on fat mass and skeletal muscle mass--the world challenge deca iron 2006]

The present study investigated the change of body composition in 8 ultra-endurance triathletes during a multi-stage ultra-endurance triathlon, where athletes had to perform one Ironman distance over 3.8 km swimming, 180 km cycling and 42.2 km running per day for 10 consecutive days. In the only 8 male successful finishers, body mass, skin fold thicknesses and circumferences of extremities were measured pre and post race in order to calculate skeletal muscle mass, percent body fat and fat mass. Bioelectrical impedance analysis was performed at the same time to determine lean body mass, percent body fat and total body water. Body mass did not change (p > 0.05), whereas skeletal muscle mass statistically significantly decreased by 1.1 kg (p < 0.05) and fat mass significantly decreased by 0.9 kg (p < 0.05).

[Traumatic rupture of the triceps brachii tendon and ipsilateral Achilles tendon]

We report on a 71-year-old male farmer who sustained an injury to the tendons of the triceps brachii and the Achilles tendon on the left side. The diagnosis was based on clinical investigations and ultrasound. The triceps brachii tendon was repaired with open transosseous sutures. Six weeks after the operation we only allowed passive mobilization. The Achilles tendon rupture was treated with a semi-open procedure. Four weeks after the operation the ankle was fixed in 30 degrees plantar flexion, followed by 2 weeks in neutral position. Full weight bearing was allowed. Six months after the operation the patient no longer had any problems with his injury. Injuries of the tendon of the triceps brachii are very rare, with an incidence of 0.8%. We could not find case reports of a simultaneous injury to another tendon in the literature.

Upper arm circumference is associated with race performance in ultra-endurance runners

OBJECTIVE

To investigate the association of anthropometric parameters to race performance in ultra-endurance runners in a multistage ultra-endurance run.

DESIGN

Descriptive field study.

SETTING

The Deutschlandlauf 2006 race in Germany, where athletes had to run 1200 km within 17 consecutive days. There were no interventions.

SUBJECTS

In total, there were 19 male Caucasian ultra-endurance runners (mean (SD) 46.2 (9.6) years, 71.8 (5.2) kg, 179 (6) cm, BMI 22.5 (1.9) kg/m(2)).

MAIN OUTCOME MEASUREMENTS

Determination of body mass, body height, length of lower limbs, skin-fold thicknesses, circumference of limbs, body mass index (BMI), percentage skeletal muscle mass (%SM), and percentage body fat (%BF) in 19 successful finishers in order to correlate anthropometric parameters with running performance.

RESULTS

A significant association of upper arm circumference with the total running time was found (p<0.05, r2 = 0.26). No significant association was found with the directly measured anthropometric properties body height, body mass, average skin-fold thickness and the circumference of thigh and calf (p>0.05). Furthermore, no significant association was observed between the running time and the calculated parameters BMI, %BF, and %SM (p>0.05).

CONCLUSIONS

In an ultra-endurance run over 1200 km within 17 consecutive days, circumference of the upper arm was the only factor associated with performance in well-experienced ultra-endurance runners. Body mass, BMI, body height, length of limbs, skin-fold thicknesses, circumference of limbs and the calculated percentage body composition of skeletal muscle mass and body fat showed no association with running performance.

[Swimming for 12 hours leads to no reduction of adipose subcutaneous tissue--a case study]

In a 12-hour swimming event, an athlete with constant body weight lost 1.1 kg of muscle mass and 21 of total body fluids whereas fat mass remained stable. Based both on the urine's specific gravity and haematological parameters, the athlete did not suffer from dehydration. We assume that loss of skeletal muscle mass occurred due to degradation of intramyocellular lipids and muscle glycogen. In order to confirm these results obtained in a case study regarding the decrease of skeletal muscle mass with stable fat mass during prolonged swimming exercise, a larger number of athletes would have to be analyzed.

[12 hours running results in a decrease of the subcutaneous adipose tissue]

A runner has completed 80 km in a 12-hour run. Prior and shortly after the run, fat and skeletal muscle mass were determined non invasively both by the bioelectrical impedance analysis and the classic skin fold method. In addition, blood and urine samples were taken in order to assess fluid balance. By applying the bioelectrical impedance analysis, the runner has increased body mass by 1.5 kg, fat-free body mass by 4.2 kg and muscle mass by 1.0 kg, whereas fat mass decreased by 4.4 kg. Since body water increased by 4.9 l, the determination of haematocrit, haemoglobin and sodium showed a haemodilution and the specific gravity of urine indicated no dehydration, we assume a substantial decrease of subcutaneous adipose tissue for energy production and intracellular oedemas. The difference between determining fat mass with the skin fold method or with the bioelectrical impedance analysis is discussed.

Effects of a Deca Iron Triathlon on body composition: a case study

We investigated energy balance and change of body composition in one athlete in a multistage triathlon, the World Challenge Deca Iron Triathlon 2006, where athletes had to perform one Ironman triathlon of 3.8 km swimming, 180 km cycling and 42.195 km running per day for ten consecutive days. In one well-experienced male ultra-endurance triathlete, we measured body mass, skinfold thicknesses and perimeters of extremities, in order to calculate skeletal muscle mass, fat mass and percentage of body fat. Energy intake was measured by analysis of nutrition, and energy expenditure was calculated using a portable heart rate monitor. This was performed to quantify energy deficit. In addition, bio-impedance measurements were performed to determine fluid metabolism. The athlete finished the race in 128 hours, 22 minutes and 42 seconds in 3rd position. Body mass decreased by 1 kilogram, skeletal muscle mass decreased by 0.9 kilograms and calculated fat mass decreased by 0.8 kilograms. Total body water increased by 2.8 liters. Total energy expenditure for the Deca Iron was 89,112 kilocalories and a total energy deficit of 11,480 kilocalories resulted. We presume that energy deficit was covered by consumption of adipose subcutaneous tissue as well as skeletal muscle mass; the degradation of muscle mass seems to lead to hypoproteinemic edemas.

[A 12 hour indoor cycling marathon leads to a measurable decrease of adipose subcutaneous tissue]

In a 12 hour indoor cycling marathon, an athlete has lost 0.4 to 1.2 kg of body mass depending on the time of measurement. Fat mass has decreased by 0.9 kg independent of the time of measurement. Calculated skeletal muscle mass increased by 0.27 to 0.67 kg - depending on the time of measurement. Due to the specific weight of urine, a possibly minimum dehydration was objectified, whereas specific weight right after exercise and 24 h after exercise had the same value. We assume that there was a substantial loss of fat mass, since repeated measurements after exercise showed an increasingly lower body weight and a constantly lower fat mass after exercise independent of the time of measurement. Increase of calculated muscle mass is considered to be due to an intramuscular oedema. In order to confirm results obtained in a case study, a larger number of athletes would have to be analyzed. A possible oedema would have to be objectified by a bioelectrical impedance analysis.

Effect of a multistage ultra-endurance triathlon on body composition: World Challenge Deca Iron Triathlon 2006

OBJECTIVE

To investigate the effect of a multistage ultra-endurance triathlon on body composition in ultra-triathletes.

DESIGN

Descriptive field study.

SETTING

The "World Challenge Deca Iron Triathlon 2006" in Monterrey, Mexico, in which every day for 10 consecutive days athletes had to perform the distance of one Ironman triathlon.

SUBJECTS

Eight male ultra-endurance athletes (mean (SD) age 40.6 (10.7) years, weight 76.4 (8.4) kg, height 175 (4) cm and body mass index (BMI) 24.7 (2.2) kg/m2).

INTERVENTIONS

None.

MAIN OUTCOME MEASUREMENTS

Determination of body mass, protein mass, body fat, per cent body fat, mineral mass, total body water, intracellular water, extracellular water and lean body mass with a direct segmental multifrequency bioelectrical impedance method before the race and after each stage in order to show changes in body composition.

RESULTS

A statistically significant decrease of body mass (-2.4 kg, p = 0.014), body fat (-5 kg, p = 0.0078) and per cent body fat (-6.4%, p = 0.0078) occurred at the end of the first day compared to values taken in the pre-race period. In contrast, at the same time, a statistically significant increase of protein mass (+0.7 kg, p = 0.035), mineral mass (+0.2 kg, p = 0.04), total body water (+1.8 litres, p = 0.042), intracellular water (+1.6 litres, p = 0.034) and lean body mass (+2.6 kg, p = 0.023) was shown. After the first day until the end of the challenge, body fat (-3 kg, p>0.05) and per cent body fat (-3.9%, p>0.05) showed a statistically significant decrease, whereas the other parameters showed no changes.

CONCLUSIONS

Athletes taking part in a multistage ultra-endurance triathlon over 10 Ironman triathlon distances in 10 consecutive days lost 3 kg of body fat; skeletal muscle mass, mineral mass and body water were unchanged.

Inter-observer agreement of ultrasonographic measurement of alpha and beta angles and the final type classification based on the Graf method

BACKGROUND

The aim of our study was to investigate the agreement of the assessment of hip ultrasonograms by different observers.

METHODS

In the period from June 3rd to December 9th 2002, four different (by experience and field) groups of observers rated all first time sonograms obtained in our hospital. The results in terms of angle and type classification were compared.

RESULTS

158 ultrasonographic images were evaluated. The inter-observer agreement for the classification "normal" (type I) versus "abnormal" (types IIa+ to IV) varied from 83% to 90% with kappa coefficients which indicated moderate (kappa 0.55) to substantial (kappa 0.71) inter-observer agreement. For one pair of observers, a better agreement could be demonstrated for the assessment of immature hips than for mature ones. The deviation for the a-angle was 0 to 16 degrees with a standard deviation of 3.15 degrees (95% CI 2.95, 3.37), and for the b-angle 0 to 26 degrees with a standard deviation of 6.1 degrees (95% CI 5.7, 6.5). The intra-class correlation coefficient was estimated to be 0.72 and 0.34 for the alpha and beta angles respectively. If the hip was immature there was no increase in the discrepancy in assessment between observers. The least agreement existed between the less experienced and the most experienced. It has not been possible to make a statement on the discrepancy with regard to initial signs of instability or decentralization of the hip joints because of the small number of hips of this type.

CONCLUSIONS

Although the spread in measured a- and b-angles is large, the inter-observer agreement for the classification showed good results. No disagreement occurred in the diagnosis of normal vs. dysplastic hips, so no severe cases have been missed. The experience and training of the investigators seemed to play an important role with regard to variability and agreement. The agreement in the assessment of immature hips was better than that of mature hips. Therefore, ultrasound examination of infant hips would appear to be a trustworthy screening method.

[Epiphyseal dysplasia--symptoms and differential diagnostic aspects]

AIM

Children complaining of hip pain most likely suffer from Perthes' disease. Similar morphological changes are seen in the hereditary diseases of the epiphyseal dysplasias which have a prevalence of about 40 of 100 000 inhabitants. We now show the differentiation between bilateral Perthes' disease, epiphyseal dysplasia and skeletal disorders like mucopolysaccharidosis and pseudoachondroplasia.

METHOD

We describe the diseases of multiple epiphyseal dysplasia and spondyloepiphyseal dysplasia on the basis of two case reports. Furthermore, we discuss differential diagnostic aspects, therapeutic options and prognosis.

RESULTS

Epiphyseal dysplasias are classified as osteochondral dysplasia. The characteristic feature of these heredopathies is short statue due to skeletal dysplasias at various sites. Multiple epiphyseal dysplasia is caused by an abnormality of enchondral ossification. A distinction is made between the severe Fairbank form, the milder Ribbing form and a mild but rather localised Meyer form. In addition to the femoral head, the spinal bodies can also be affected by the same enchondral ossification disorders and this is defined as spondyloepiphyseal dysplasia.

CONCLUSION

The diagnosis of a Perthes' disease can be made from an X-ray of the hip, showing either an advanced necrosis of the femoral head or early signs of it. Typical radiological findings allow the differentiation to other skeletal dysplasias like epiphyseal dysplasia and metabolic disorders.

Inter-observer agreement of ultrasonographic measurement of alpha and beta angles and the final type classification based on the Graf method

BACKGROUND

The aim of our study was to investigate the agreement of the assessment of hip ultrasonograms by different observers.

METHODS

In the period from June 3rd to December 9th 2002, four different (by experience and field) groups of observers rated all first time sonograms obtained in our hospital. The results in terms of angle and type classification were compared.

RESULTS

158 ultrasonographic images were evaluated. The inter-observer agreement for the classification "normal" (type I) versus "abnormal" (types IIa+ to IV) varied from 83% to 90% with kappa coefficients which indicated moderate (kappa 0.55) to substantial (kappa 0.71) inter-observer agreement. For one pair of observers, a better agreement could be demonstrated for the assessment of immature hips than for mature ones. The deviation for the a-angle was 0 to 16 degrees with a standard deviation of 3.15 degrees (95% CI 2.95, 3.37), and for the b-angle 0 to 26 degrees with a standard deviation of 6.1 degrees (95% CI 5.7, 6.5). The intra-class correlation coefficient was estimated to be 0.72 and 0.34 for the alpha and beta angles respectively. If the hip was immature there was no increase in the discrepancy in assessment between observers. The least agreement existed between the less experienced and the most experienced. It has not been possible to make a statement on the discrepancy with regard to initial signs of instability or decentralization of the hip joints because of the small number of hips of this type.

CONCLUSIONS

Although the spread in measured a- and b-angles is large, the inter-observer agreement for the classification showed good results. No disagreement occurred in the diagnosis of normal vs. dysplastic hips, so no severe cases have been missed. The experience and training of the investigators seemed to play an important role with regard to variability and agreement. The agreement in the assessment of immature hips was better than that of mature hips. Therefore, ultrasound examination of infant hips would appear to be a trustworthy screening method.

Experiences in diagnosis and treatment of hip dislocation and dysplasia in populations screened by the ultrasound method of Graf

Ultrasound investigation of the hip according to Graf is performed, whenever possible, as a routine screening test for hip dysplasia and dislocation in neonates. However, in spite of screening, hip dysplasia and/or dislocation is identified in a number of children after the third month of life only. The present study presents an analysis of reasons and causes. Between August 1999 and July 2001 children aged between six months and five years were documented, in whom the diagnosis of hip dysplasia or dislocation was made, despite normal ultrasound findings at primary investigation and who required non operative or operative treatment by a specialist surgeon working in Switzerland in paediatric orthopaedics. The study included 26 children (17 girls / 9 boys). Hip dysplasia and/or dislocation was diagnosed between the age of 6 days and 41 months. Twelve children had to be excluded from the sample (n = 26), four were infants who had basic neurological disorders or multiple anomalies and there were eight children from abroad whose original documentation could not be obtained. Analysis of the remaining 14 children showed that 43% were misdiagnosed (n = 6) and a treatment error occurred in 36% (n = 5) of cases. One child presented with a teratogenic hip dislocation. In two other infants with normal primary ultrasound findings, hip dysplasia was identified radiographically once the child started to walk. Delayed diagnosis can be the result of technical errors or misinterpretation. The six patients meeting the criteria of misinterpretation can be expressed as a rate of 0.04% of all births. However, even if the disorder is correctly diagnosed, its identification and treatment may be inadequate or fail to produce the desired results. This was the case for five of the children, that is, for a rate of 0.03% of births.

Experiences in diagnosis and treatment of hip dislocation and dysplasia in populations screened by the ultrasound method of Graf

Ultrasound investigation of the hip according to Graf is performed, whenever possible, as a routine screening test for hip dysplasia and dislocation in neonates. However, in spite of screening, hip dysplasia and/or dislocation is identified in a number of children after the third month of life only. The present study presents an analysis of reasons and causes. Between August 1999 and July 2001 children aged between six months and five years were documented, in whom the diagnosis of hip dysplasia or dislocation was made, despite normal ultrasound findings at primary investigation and who required non operative or operative treatment by a specialist surgeon working in Switzerland in paediatric orthopaedics. The study included 26 children (17 girls / 9 boys). Hip dysplasia and/or dislocation was diagnosed between the age of 6 days and 41 months. Twelve children had to be excluded from the sample (n = 26), four were infants who had basic neurological disorders or multiple anomalies and there were eight children from abroad whose original documentation could not be obtained. Analysis of the remaining 14 children showed that 43% were misdiagnosed (n = 6) and a treatment error occurred in 36% (n = 5) of cases. One child presented with a teratogenic hip dislocation. In two other infants with normal primary ultrasound findings, hip dysplasia was identified radiographically once the child started to walk. Delayed diagnosis can be the result of technical errors or misinterpretation. The six patients meeting the criteria of misinterpretation can be expressed as a rate of 0.04% of all births. However, even if the disorder is correctly diagnosed, its identification and treatment may be inadequate or fail to produce the desired results. This was the case for five of the children, that is, for a rate of 0.03% of births.

Does it always have to be Perthes' disease? What is epiphyseal dysplasia?

The epiphyseal dysplasias are classified as osteochondral dysplasias in a heterogeneous group of skeletal dysplasias. The common feature of these hereditary conditions is short stature attributable to skeletal dysplasia at various sites. Multiple epiphyseal dysplasia and spondyloepiphyseal dysplasia are of interest to the authors, because the two syndromes are similar in their morphologic features and at first glance suggest the diagnosis of Perthes' disease. Spondyloepiphyseal dysplasia (Wiedemann-Spranger syndrome) is a disorder of growth in which there is an abnormality of enchondral ossification affecting the vertebral bodies and the epiphyses of the long bones. The two forms are the more severe congenita form (Type I), which is inherited as an autosomal dominant condition and is associated with a highly disproportional reduction in growth and severe coxa vara, and the milder tarda form which is an X-linked recessive condition, in which growth in adolescence is defective after normal childhood development. Multiple epiphyseal dysplasia is an abnormality of enchondral ossification, especially of the femoral head epiphysis, and it is an autosomal dominant condition. Depending on its severity, a distinction is made between the severe Fairbank form, the milder Ribbing form, and a mild localized Meyer form.

Potentially therapeutically relevant differences of antisense oligonucleotide uptake in CD34+ hematopoietic stem cells, leukemic blasts and cancer cells from patients

Antisense oligonucleotide (ON) technology, e.g. against drug resistance or antiapoptotic factors, may play an important role in future cancer chemotherapy. An unanswered question in this field is the capacity for uptake of antisense molecules in normal and malignant patients' cells. Therefore, we examined the cellular uptake of FITC-labeled phosphorothioate modified ONs in: i) cells from the T-lymphoblastoid cell line CCRF-CEM, ii) CD34+ hematopoietic progenitors from healthy donors, iii) blasts from ALL or AML patients, iv) cells from the ovarian cancer cell line A2780 and v) cancer cells from malignant fluids. The cationic polymer ExGen was taken as a carrier for transfection, while FITC-ON uptake was evaluated by flow cytometry. We found marked differences between these cell types. Cancer cells from the cell line A2780 and from patients showed a distinctly enhanced uptake compared to hematopoietic progenitors and leukemic blasts. Since bone marrow toxicity substantially limits any conventional chemotherapeutic regimen, a better ON uptake in cancer cells compared to hematopoietic precursors might give an advantage for therapeutic approaches using e.g. ON-based chemosensitization.

Heat-induced segmental necrosis after reaming of one humeral and two tibial fractures with a narrow medullary canal

In three cases referred to our clinic (a simple fracture of the humeral shaft, a simple, closed fracture, and a wedge fracture of the mid-third of the tibia), bone necrosis had resulted from excessive heat produced by reaming extremely narrow medullary cavities (5-5.5 mm diameter) with the 9 mm front-cutting reamer as part of a reamed nailing procedure. In any one case, different degrees of damage can occur from the metaphysis to the diaphysis. Based on the clinical course and the histological evaluation, we postulate that heat-induced damage can be divided into four degrees of severity (0-3): Grade 0: no damage; no devascularization, no heat-induced damage. Grade 1: The heat damaged zone is cut away during subsequent reaming, the only damage is devascularization. Grade 2: The damaged zones are not eliminated by subsequent reaming. The bone is devascularized and heat damaged. Grade 3: The entire cross section of the bone including the periosteum is devitalized by exposure to excessive heat. Depending on the severity of additional damage to the soft tissues, grave consequences are to be expected and further operations are unavoidable. The effects of heat-induced damage are particularly critical in the presence of infection (cases 2 and 3). The fundamental aspects and the extent of heat necrosis will be discussed. After discussion with the AO Technical Commission on the cause of heat-induced necrosis, we would recommend the following preventive measures: 1. preoperative measurement of the smallest diameter of the medullary cavity in two planes. 2. reaming with the standard instrumentation (9 mm) only if the medullary cavity has a diameter of at least 8 mm at its narrowest point. 3. Extremely narrow cavities should first be reamed manually or an alternative to nailing should be sought. 4. It is strongly recommended that only sharp reamers be used in such cases and blunt or damaged reamers replaced.

The physics of heat generation during reaming of the medullary cavity

Clinical experience of special cases of reaming of a small diameter medullary cavity has shown a remarkable temperature increase with associated thermal damage to the surrounding tissue. By applying known solutions of the heat conductivity equation to simplified models of a reamer to bone tube system, the effects of the most important parameters on heat generation and temperature distribution are explained. The results allow a quantitative assessment of reaming techniques for small cavities which gives rise to the following recommendations: reamers used consecutively should not increase more than 0.5 mm in diameter; blunt instruments must be replaced or sharpened; prepare very narrow medullary cavities with the small diameter hand reamer; if the reamer ceases to advance do not increase the axial force but withdraw it and check the reamer and the temperature. Cooling, cleaning and replacement of the reamer should be considered, if appropriate.

Further studies on HTLV-I associated myelopathy in Argentina

We report 10 HTLV-I virus seropositive subjects, eight of them with HTLV-I associated myelopathy (HAM), two of them also infected with HIV as well as two asymptomatic HTLV-I+ relatives of two unrelated patients. HTLV-I is endemic in several tropical areas, where it causes different neurological diseases. Only few patients have been reported in our country since 1994. We studied 8 patients, who fulfilled the clinical criteria for chronic spastic paraplegia, and 2 other non-symptomatic HTLV-I seropositive relatives, with electromyography (EMG), motor and sensory conduction velocities (NCV), somatosensory, visual and brainstem auditory evoked potentials (SSEP, VEP and BAEP), Magnetic Resonance Images (MRI) and cerobrospinal fluid (CSF) analysis. The latter was carried out only in seven symptomatic patients. In every case positive ELISA tests for HTLV-I/II were confirmed by Western Blot. The two asymptomatic persons were clinically and electromyographically assessed, one of them was also submitted to SSEPs studies. Three patients were males. Patient's ages ranged from 5 to 65 years old. All symptomatic patients showed muscular weakness, spasticity with pyramidal signs and sphincter disturbances. Five of them had paresthesias and 2 had burning pain on their feet. The EMGs and the NCVs were normal in 7 patients and in the 2 asymptomatic ones. SSEPs, obtained by stimulating the posterior tibial nerves, were impaired in 7 patients and in the asymptomatic person who received the procedure. The 7 symptomatic patients who underwent lumbar puncture had positive tests for HTLV-I in CSF, 3 out of these 7 patients had also high protein levels and 4 had increased number of lymphocytes. In 2 patients intrathecal IgG production could also be demonstrated. MRI were normal in 7 patients and in the 2 asymptomatics, the exception being a female who had bilateral hyperintense lesions in cerebral white matter in T2. In conclusion, tropical spastic paraparesis is apparently a rare disorder in Argentina. However, some cases have been reported recently. Most probably, its prevalence is currently underestimated. Its diagnosis should be considered in every patient with progressive spastic paraplegia.

Schistosoma mansoni in IL-4-deficient mice

Immunopathology and immune responses to Schistosoma mansoni were examined in IL-4 -/- mice. IL-5 and IL-10 production by lymphoid cells stimulated with soluble egg antigen (SEA), peripheral eosinophilia and serum levels of soluble IL-4 receptor but not IgE were all significantly elevated over background normal levels in IL-4 -/- mice as a result of infection. Additionally, IL-10 and IL-5 in addition to IL-2 and IFN-gamma transcripts were equally evident in diseased liver tissue from infected IL-4 -/- and wild-type mice. Nevertheless, analysis of antigen-stimulated IL-2, IL-4, IL-5, IL-10 and IFN-gamma production by lymphoid organ cells from infected or egg-injected IL-4 -/- mice revealed a more Th1-like pattern of cytokine production (IFN-gamma > IL-5) than in (wild-type) mice in which a stronger type 2 response to SEA was detectable (IL-4, IL-5 > IFN-gamma). Despite this, at 8 and 16 weeks after infection, liver pathology, as indicated by the size, cellularity, cellular composition and collagen content of granulomas, was similar in IL-4 -/- and wild-type animals. As in wild-type animals, granuloma size at week 16 was smaller than at week 8, indicating that modulation had occurred in the absence of IL-4. Differences in pathology were seen only when eggs were experimentally embolized to the lungs, in which case IL-4 -/- mice made smaller granulomatous responses than did wild-type animals. These data clearly show that IL-4 is not necessary for the hepatic granuloma formation which occurs during experimental schistosomiasis.

Topical treatment of life threatening haemoptysis from aspergillomas

BACKGROUND

The efficacy of topical treatment of 12 episodes of severe life threatening haemoptysis from a pulmonary aspergilloma in 11 patients is reviewed.

METHODS

A retrospective review was performed on five white and six African-American patients of mean age 49 years. The underlying diseases were bronchiectasis, sarcoidosis, tuberculosis, or histoplasmosis. The patients were prospectively considered poor surgical risks because they had a forced expiratory volume in one second (FEV1) of < 50% predicted and an arterial oxygen tension (PaO2) of < 7.95 kPa breathing room air. As surgical intervention was not possible, local intracavitary instillation of sodium or potassium iodide was performed. Two patients were previously treated with amphotericin B. In one patient sodium iodide alone was used and in the remaining eight potassium iodide alone was instilled. The transcricothyroid approach was used in six patients and the percutaneous approach in five.

RESULTS

Haemoptysis ceased within 72 hours in all patients after the instillation of sodium or potassium iodide. There was no morbidity or mortality, and side effects included slight irritation on instillation of the iodide solution and occasional cough which was easily controlled. All patients were alive at least one year later.

CONCLUSION

Intracavitary treatment is a viable option in the poor risk patient with life threatening haemoptysis from an aspergilloma.

[Acute isolated ventral dislocation of the head of the fibula]

We present the case of a 19-year-old soccer player who had sustained a valgus, external rotation trauma to the flexed knee with traumatic anterolateral dislocation of the proximal tibiofibular joint and concomitant partial peroneal nerve palsy, which went away within a few days. We discuss the clinical features and treatment by temporary screw fixation of the proximal tibiofibular joint, as well as the results in the literature where predominantly conservative treatment is reported.

Inflammatory cytokines in the BAL of patients with ARDS. Persistent elevation over time predicts poor outcome

BACKGROUND

Inflammatory cytokines (ICs) are important modulators of injury and repair. ICs have been found to be elevated in the BAL of patients with both early and late ARDS. We tested the hypothesis that recurrent injury to the alveolocapillary barrier and amplification of intra-alveolar fibroproliferation observed in nonresolving ARDS is related to a persistent inflammatory response. For this purpose, we obtained serial measurements of BAL IC and correlated these levels with lung injury score (LIS), BAL indexes of endothelial permeability (albumin, total protein [TP]), and outcome.

METHODS

We prospectively studied 27 consecutive patients with severe medical ARDS. Using enzyme-linked immunosorbent assay methods, levels of tumor necrosis factor-alpha (TNF-alpha) and interleukins (IL) 1 beta, 2, 4, 6, and 8 were measured at frequent intervals in both plasma and BAL. In 22 patients, bilateral BAL was obtained on day 1 of ARDS and at weekly intervals when possible. Right and left BALs were analyzed separately for IC levels, total cell count and differential, albumin, TP, and quantitative bacterial cultures.

RESULTS

On day 1 of ARDS, the 10 nonsurvivors had significantly higher (p = 0.0002) BAL TNF-alpha, IL-1 beta, IL-6, and IL-8 levels, which remained persistently elevated over time, indicating a continuous injury process. In contrast, the 12 survivors had a lesser elevation and a rapid reduction over time. Initial BAL IL-2 and IL-4 levels were significantly higher in patients with sepsis (p = 0.006); both increased over time in survivors and nonsurvivors. BAL levels of TNF-alpha, IL-1 beta, IL-6, and IL-8 correlated with BAL albumin and TP concentrations but not with LIS or ratio of arterial oxygen tension to inspired oxygen concentration. BAL: plasma ratios were elevated for all measured cytokines, suggesting a pulmonary origin. On day 1 of ARDS, nonsurvivors had significantly higher (p = 0.04) BAL: plasma ratios for TNF-alpha, IL-1 beta, IL-6, and IL-8. Over time, BAL:plasma ratios for TNF-alpha, IL-1 beta and IL-6 remained elevated in nonsurvivors and decreased in survivors.

CONCLUSIONS

Our findings indicate that an unfavorable outcome in ARDS is associated with an initial, exaggerated, pulmonary inflammatory response that persists unabated over time. Plasma IC levels parallel changes in BAL IC levels. The BAL:plasma ratio results suggest, but do not prove, a pulmonary origin for IC production. BAL TNF-alpha, IL-1 beta, and IL-8 levels correlated with BAL indices of endothelial permeability. In survivors, reduction in BAL IC levels over time was associated with a decline in BAL albumin and TP levels, suggesting effective repair of the endothelial surface. These findings support a causal relationship between degree and duration of lung inflammation and progression of fibroproliferation in ARDS.

Persistent elevation of inflammatory cytokines predicts a poor outcome in ARDS. Plasma IL-1 beta and IL-6 levels are consistent and efficient predictors of outcome over time

BACKGROUND

Inflammatory cytokines have been related to the development of adult respiratory distress syndrome (ARDS), shock, and multiple organ dysfunction syndrome (MODS). We tested the hypothesis that unfavorable outcome in patients with ARDS is related to the presence of a persistent inflammatory response. For this purpose, we evaluated the behavior of inflammatory cytokines during progression of ARDS and the relationship of plasma inflammatory cytokines with clinical variables and outcome.

METHODS

We prospectively studied 27 consecutive patients with severe medical ARDS. Plasma levels of tumor necrosis factor alpha (TNF-alpha) and interleukins (ILs) 1 beta, 2, 4, 6, and 8 were measured (enzyme-linked immunosorbent assay [ELISA] method) on days 1, 2, 3, 5, 7, 10, and 12 of ARDS and every third day thereafter while patients were receiving mechanical ventilation. Subgroups of patients were identified based on outcome, cause of ARDS, presence or absence of sepsis, shock, and MODS at the time ARDS developed. Subgroups were compared for levels of plasma inflammatory cytokines on day 1 of ARDS and over time.

RESULTS

Of the 27 patients, 13 survived ICU admission and 14 died (a mortality rate of 52%). Overall mortality was higher in patients with sepsis (86 vs 38%, p < 0.02). The mean initial plasma levels of TNF-alpha, IL-1 beta, IL-6, and IL-8 were significantly higher in nonsurvivors (p < 0.0001) and in those patients with sepsis (p < 0.0001). Plasma levels of IL-1 beta (p < 0.01) and IL-6 (p = 0.03) were more strongly associated with patient outcome than cause of ARDS (p = 0.8), lung injury score (LIS), APACHE II score, sepsis (p = 0.16), shock, or MODS score. Plasma levels of TNF-alpha, IL-1 beta, IL-6, and IL-8 remained significantly elevated over time (p < 0.0001) in those who died. Although it was the best early predictor of death (p < 0.001), plasma IL-2 > 200 pg/mL lost its usefulness after the first 48 h. A plasma IL-1 beta or IL-6 level > 400 pg/mL on any day in the first week of ARDS was associated with a low likelihood of survival.

CONCLUSIONS

Our findings indicate that unfavorable outcome in acute lung injury is related to the degree of inflammatory response at the onset and during the course of ARDS. Patients with higher plasma levels of TNF-alpha, IL-1 beta, IL-6, and IL-8 on day 1 of ARDS had persistent elevation of these inflammatory cytokines over time and died. Survivors had lesser elevations of plasma inflammatory cytokines on day 1 of ARDS and a rapid reduction over time. Plasma IL-1 beta and IL-6 levels were consistent and efficient predictors of outcome.

[Cerebellar syndrome caused by amiodarone]

Amidarone (AMD) is an antiarrhythmic drug with side effects on the nervous system. Cerebellum is seldom involved: We describe the case of a 56 years old male patient with a history of 4 month of cerebellar involvement characterized by gait unsteadiness, ataxia, nistagmus and vertigo. He was on treatment with AMD because of ventricular arrythmia. The cerebellar syndrome progressively disappeared after drug withdrawal and he was symptoms-free 4 months later. Similar symptoms appeared after another one month of automedication with the same drug. Structural lesions, metabolic, nutritional deficiencies or toxics were excluded. Mechanisms of cerebellar toxicity of AMD are yet unknown. The knowledge of the toxic effects of this drug, widely used in our country, would allow its early recognition.

An acidic fibroblast growth factor stimulates DNA synthesis, inhibits collagen and alkaline phosphatase synthesis and induces resorption in bone

We have examined the effects of an acidic fibroblast growth factor (aFGF) on bone cell growth and differentiation and on osteoclastic resorption using rat fetus organ cultured calvariae and long bones, respectively. Low concentrations of this aFGF stimulated DNA synthesis (1.28 ng/ml) and inhibited collagen formation (1.28 ng/ml) and alkaline phosphatase activity (0.64 ng/ml) in the isolated calvariae. The inhibition of collagen synthesis was independent of the aFGF's mitogenic effect, and was evident in periosteum-containing and periosteum-free bones, pointing to osteoblasts as the aFGF-responsive cells. Our preparation of aFGF enhanced resorption in the long bones by a calcitonin-inhibitable mechanism. PGE2 release accompanied and indomethacin prevented the enhancement of resorption. By contrast, indomethacin did not block the stimulation of DNA and collagen synthesis caused by our aFGF. These results indicate that our aFGF exerts a PGE2-independent effect on DNA synthesis and collagen synthesis and a PGE2-dependent effect on resorption in bone tissue in vitro.

Bone-resorbing agents promote and interferon-gamma inhibits bone cell collagenase production

Parathyroid hormone, prostaglandin E2, 1 alpha,25-dihydroxyvitamin D3, interleukin-1, tumor necrosis factor alpha, and epidermal growth factor, all known stimulators of bone resorption, markedly enhanced collagenase secretion by rat fetus osteoblastlike cells in primary culture as judged by enzyme-linked immunosorbent assay. Untreated cells contained no immunostainable or extractable collagenase. Collagenase was detected in the treated cells and media only after 1-3 h of treatment, and there was no increment in collagenase activity when cells were treated in the presence of actinomycin D or cycloheximide. Cells secreted collagenase in a latent form and also elaborated collagenase inhibitor; chromatographic separation of collagenase from collagenase inhibitor and subsequent activation of the collagenase with trypsin yielded the active species in stimulated but not in unstimulated cells. The ability of individual prostanoids, among seven tested, to promote collagenase production correlated positively with their reported capacity to promote bone resorption. Interferon-gamma (IFN-gamma), a known resorption inhibitor, blocked the increment in collagenase production caused by all agents tested. These results indicate a close linkage between stimulation of bone resorption and collagenase production by osteoblastlike cells. Various resorption stimulators, including some not previously tested for effects on collagenase, augment the de novo synthesis and secretion of collagenase and act by an IFN-gamma-inhibitable mechanism.

Prostaglandins change cell shape and increase intercellular gap junctions in osteoblasts cultured from rat fetal calvaria

Mounting experimental evidence indicates that osteoblasts may be cellular intermediaries in the local activation of bone remodeling. To elucidate the role of these cells in activation, we examined the effects of prostaglandins (PGs), known resorption stimulators, on cell shape and intercellular junctional relationships in osteoblasts cultured from rat fetal calvaria. Exposure to PGE2 and PGE1, promoters of bone resorption, rapidly (within 20 min) converted the osteoblasts from a flattened to a stellate shape (shape change), and markedly increased the appearance of intercellular (gap) junctions within 10 min. Both effects were directly related to the prostaglandin concentration, as little as 1 nM being effective. PGE1, but not PGB1, PGF1 alpha, PGD2, and PGF2 alpha, mimicked the substantial effect of PGE2 on shape change. Shape change and gap junction formation appear to arise independently. PTH, an inducer of shape change, did not affect the number of gap junctions appreciably. Colchicine, a microtubule polymerization inhibitor, and trifluoperazine, an inhibitor of calmodulin action, blunted PGE2-mediated shape change but not the effect of PGE2 on gap junctions. Shape change and gap junction formation may be important events in local activation, shape changes in surface osteoblasts serving to expose bone surfaces which are chemotactic for osteoclasts and gap junctions propagating locally initiated activation messages.

Fetal rat chondrocytes sequentially elaborate separate growth- and differentiation-promoting peptides during their development in vitro

Chondrocytes isolated from the calvaria of rat fetuses proliferate and form cartilage when cultured in a chemically defined, serum-free medium, suggesting that they may elaborate self-regulatory factors. Conditioned media obtained from these chondrocytes stimulated DNA synthesis and proliferation when added to separate cultures of chondrocytes and the closely related osteoblast-like cells, but were not very effective in skin fibroblasts isolated from the same fetuses, as judged by [3H]thymidine incorporation and cell proliferation. Chondrocyte-conditioned medium also promoted chondrocyte differentiation, augmenting 35SO4 incorporation, and the accumulation of type II collagen and cartilage-specific proteoglycan. Stimulation of growth and differentiation appears to be attributable to separate activities, released into the medium sequentially by the cultured chondrocytes during their proliferation and maturation phases. Media obtained from growing chondrocytes stimulated growth, but had little effect on 35SO4 incorporation. Media obtained from mature cultures promoted growth as well as 35SO4 incorporation. The mitogenic and sulfation activities were trypsin inhibitable, but exhibited different solubility characteristics and striking differences in their patterns of elution from gel filtration columns. These results suggest that chondrocytes elaborate autostimulatory peptides, the biological activities of which mirror, at least in part, the developmental stage of the donor cells.

Comparison of three methods for detection of prolonged experimental trichinellosis in pigs

Three methods were employed for the diagnosis of porcine trichinellosis. The pooled sample digestion method and trichinoscopy served as European Community (EC) reference techniques, whereas the reliability of the Enzyme Linked Immunosorbent Assay (ELISA) was tested by 11 laboratories of the European Community and Sweden. Three groups of 6 piglets each were orally inoculated with 50, 150 and 1500 Trichinella spiralis larvae into each animal. Another group of 6 animals served as a non-infected control. Animals were slaughtered and serum and muscle samples were collected at Weeks 4, 12 and 40. The material was mailed under code and examined in all participating laboratories. ELISA proved to be a sensitive technique. ELISA micro assay was the most sensitive procedure. Of the direct techniques the reference pooled sample digestion method was more sensitive than trichinoscopy. It was concluded that both micro and macro ELISA can be used with confidence for the detection of low grade, longstanding experimental T. spiralis infections in swine.

Adriamycin inhibits PTH-mediated but not PGE2-mediated stimulation of cyclic AMP formation in isolated bone cells

We have examined the effect of adriamycin, an anthracycline antibiotic which modifies plasma membrane functions, on the cyclic AMP response to PTH and PGE2 in isolated osteoblastlike cells. Adriamycin blunted the increment in bone cell cyclic AMP caused by exposure to PTH. This effect appeared rapidly (within 3 min after bone cells were exposed to adriamycin) and disappeared soon after exposure of adriamycin-treated cells to adriamycin-free incubation medium. Inhibition was evident over the entire time course of PTH action, at low as well as high PTH concentrations, and was one-half maximal at 31 microM adriamycin. It could not be attributed to alterations in cyclic AMP exodus, degradation or interference with the cyclic AMP assay, nor to impaired cell viability. Adriamycin also reduced the stimulatory effect of PTH on adenylate cyclase activity in a crude plasma membrane preparation. By contrast, adriamycin failed to modify the effects of PGE2 on cyclic AMP generation in intact bone cells, and on adenylate cyclase activity in broken cells. Moreover, concentrations of adriamycin that blunted the effect of PTH on adenylate cyclase activity did not inhibit the stimulatory effects of sodium fluoride or of GppNHp. These results suggest that adriamycin selectively alters the interaction between PTH and its receptor or impairs the transmission of information from hormone-receptor complex to adenylate cyclase (or both), perhaps by binding to specific lipid domains in the plasma membrane. Structural analogues of adriamycin, which vary in their lipophilic properties, also varied in their capacity to perturb the cyclic AMP response.(ABSTRACT TRUNCATED AT 250 WORDS)

Calcitonin response in circulating human lymphocytes

The concentration of cAMP increases in human mononuclear leukocytes after exposure to salmon calcitonin (SCT). This response is lost when the cells are separated into adherent (monocytic) and nonadherent (lymphocytic) cells, although the appropriate response to prostaglandin E2 remains in both groups. Adherent and nonadherent cells, each cultured alone for 16 h, do not regain the SCT response. Coculturing adherent and nonadherent cells together for 16 h restores the SCT response in the lymphocytes. The addition of a cyclooxygenase inhibitor to this culture system prevents development of the SCT response. The SCT response may be induced in nonadherent cells by culturing them for 16 h in medium previously conditioned by the growth of mixed mononuclear leukocytes.

A high affinity, calmodulin-responsive (Ca2+ + Mg2+)-ATPase in isolated bone cells

Although acute alterations in Ca2+ fluxes may mediate the skeletal responses to certain humoral agents, the processes subserving those fluxes are not well understood. We have sought evidence for Ca2+-dependent ATPase activity in isolated osteoblast-like cells maintained in primary culture. Two Ca2+-dependent ATPase components were found in a plasma membrane fraction: a high affinity component (half-saturation constant for Ca2+ of 280 nM, Vmax of 13.5 nmol/mg per min) and a low affinity component, which was in reality a divalent cation ATPase, since Mg2+ could replace Ca2+ without loss of activity. The high affinity component exhibited a pH optimum of 7.2 and required Mg2+ for full activity. It was unaffected by potassium or sodium chloride, ouabain or sodium azide, but was inhibited by lanthanum and by the calmodulin antagonist trifluoperazine. This component was prevalent in a subcellular fraction which was also enriched in 5'-nucleotidase and adenylate cyclase activities, suggesting the plasma membrane as its principal location. Osteosarcoma cells, known to resemble osteoblasts in their biological characteristics and responses to bone-seeking hormones, contained similar ATPase activities. Inclusion of purified calmodulin in the assay system caused small non-reproducible increases in the Ca2+-dependent ATPase activity of EGTA-washed membranes. Marked, consistent calmodulin stimulation was demonstrated in membranes exposed previously to trifluoperazine and then washed in trifluoperazine-free buffer. These results indicate the presence of a high affinity, calmodulin-sensitive Ca2+-dependent ATPase in osteoblast-like bone cells. As one determinant of Ca2+ fluxes in bone cells, this enzyme may participate in the hormonal regulation of bone cell function.

The patellar syndrome-a complication secondary to endoprosthetic replacement of the knee joint: a retrospective study of 102 knee joints over a period of seven years

Until recently, loosening, infection and fractures of the prosthesis have been considered the only major complications of otherwise good initial results with total endoprosthetic replacement of the knee joint; however, another serious long term complication has become apparent. Severe degenerative changes of the retropatellar cartilage are being observed, which seem to be caused by a possible axial malalignment of the knee, progression of a preexisting retropatellar arthrosis, and additional metallosis induced by the prosthesis. The resulting symptoms and complaints, in accordance with Debeyre, are summarized by the term Patellar Syndrome. Our studies indicate that these symptoms develop in 50% of all patients with a total knee endoprosthesis within three years after surgery. In 10% of the cases these symptoms are severe enough to require additional surgical intervention.