Analysis of postural stability following posterior spinal fusion in adolescents with idiopathic scoliosis

This study uses experimental data acquired from adolescents with idiopathic scoliosis to assess their postural control during quiet standing before and after posterior spinal fusion. Statistically significant differences were seen when comparing the pre- and post-surgical measures of balance calculated from data for three different test conditions.

[Chronic musculo-skeletal pain in Switzerland: patient care from the view of physicians and patients]

A considerable percentage of the population suffers from chronic musculoskeletal pain (CMP) and patient management does not appear to be optimal. The aim of the present investigations was to assess and evaluate epidemiologic data and discover eventual deficits in patient management. This investigation included several sequential steps: First a European study including Switzerland evaluated the prevalence and characteristics of patients with CMP as well as of the treating physicians. The results were discussed and elaborated in two workshops, where general practitioners and patients were included. In a further step the results of these workshops were evaluated again in a telephone survey addressing patients and physicians both in the French and German speaking parts of Switzerland. Considerable deficits were discovered in the management of patients with CMP: In 35% no firm diagnosis was established, the life quality was considerably reduced in about 13 of the patients, the patients' information on their disorders were found to be rather limited, furthermore, there were misconceptions about medical treatment. The two workshops confirmed the results of the first study. The causes of pain often remained unclear, there were considerable communication problems between patient and physician, medical treatment appeared to be inappropriate, and there were deficits in the time management during consultations. The telephone survey confirmed these deficits. In conclusion management of patients with CMP is characterized by considerable deficits such as missing or unclear diagnosis, misconceptions in medical contexts and treatment. Many of the deficits may be improved and call for measures for optimizing the management of patients with CMP.

Multichannel Doppler transmission grating spectrometer at the Alcator C-Mod tokamak

Upgrades to an existing transmission grating spectrometer for visible light used for Doppler velocity and temperature measurements at the Alcator C-Mod tokamak are given. These include a new Princeton Instruments Photonmax 512B charge-coupled device and a four channel fiber optic input. These together allow improvements to the signal level, time resolution, and the number of spatial channels. The fiber optic input allows four simultaneous spatial channels each of which offers a larger percentage of input light flux when compared to the standard fiber slit combination. The "on chip" amplification combined with versatile pixel binning further increases the signal to noise ratio allowing a continuous acquisition of spectra every 8 ms. The error bars for extracted velocity and temperature values are potentially smaller owing to the smaller pixel size and increased light flux which allow a more detailed line shape and simplifies line fitting. Examples of time and space resolved spectra are shown and further improvements are discussed.

Application of a bi-planar postural stability model in children with cerebral palsy

This study presents initial results from a bi-planar model used to investigate the neurological factors affecting balance deficits in children with diplegic cerebral palsy (CP). The model uses an inverted pendulum to describe sway in both the anteroposterior (AP) and mediolateral (ML) planes. The study presents Center of Pressure (COP) data from 17 children diagnosed with spastic diplegic CP using two standard AMTI force plates. Sway metrics in the time and frequency domains in the AP and ML planes were calculated and compared to simulations produced by the model. The proposed bi-planar model successfully reproduced sway signals acquired from experimental (clinical) data.

Characterisation of microstructures formed in isopropyl palmitate/water/Aerosol OT:1-butanol (2:1) system

The aim of this work was to determine the type and microstructure of microemulsion samples formed in IPP/water/AerosolOT:1-butanol (2:1) systems as a case study for the investigation of microemulsions. The concentration of the surfactant/cosurfactant mixture was kept constant while the ratio of water to oil was varied. Several techniques were used to investigate the types and phase transitions of the microemulsion formulations. The experimental methods used included visual observation cross-polarized light microscopy (PLM) appearance, conductivity, viscosity, cryo-field emission scanning electron microscopy (cryo-FESEM), differential scanning calorimetry (DSC), nuclear magnetic resonance (NMR), and fluorescence resonance energy transfer (FRET). Taken together, the results of the various techniques imply that the systems investigated are undergoing two transitions as a function of water concentration. Between 10-15%w/w of water, the systems change from headgroup hydrated surfactant solutions in oil (or possibly very small reversed micellar systems) to w/o microemulsions. These systems then change to o/w microemulsions between 25-30%w/w of water. The transitions however, appear to be gradual, as for example the DSC data indicates a transition between 15-20%w/w of water. Furthermore, for some methods the changes observed were very weak, and only with supportive data of other techniques can the phase behaviour of the microemulsion systems be interpreted with confidence. Interestingly, no indication of the presence of a bicontinuous intermediate microstructure was found. Liquid crystal formation was detected in samples containing 55%w/w of water.

Quality of life and psychological adjustment in children and adolescents with neurofibromatosis type 1

OBJECTIVE

To assess quality of life (QoL) and psychological adjustment in children and adolescents with neurofibromatosis type 1 (NF1).

STUDY DESIGN

Forty-six patients with NF1 were investigated between the ages of 7 and 16 years (mean, 11.6 years), with children and parents used as informants. TNO-AZL Questionnaire for Children's Health-Related Quality of Life and Child Behavior Checklist scores were compared with healthy reference groups. Predictive values of sociodemographic variables, illness-related variables, and family-related variables for quality of life and psychological adjustment were assessed.

RESULTS

Most dimensions of QoL in NF1 children and adolescents were different from reference values. Deviations in the NF1 group were an impairment of motor, cognitive, and social functioning and a reduction of positive and negative emotions. Also, psychological adjustment in patients with NF1 was significantly impaired compared with normal subjects. Illness-related variables had a negative impact on the emotional domain of QoL. Good family relationships positively affected both QoL and psychological adjustment.

CONCLUSIONS

QoL and psychological adjustment are impaired in children and adolescents with NF1. Illness-related variables and the quality of family relationships are important predictors.

Perfusion-contractility matching during Fontan circulation

We investigated the relationship between coronary perfusion pressure (CPP) and myocardial contractility and the effects of an acute elevation of right atrial pressure (RAP) on this relationship in an experimental model of Fontan circulation in 6 anesthetized open-chest dogs with isolated perfused coronary arteries. The relationship between CPP and Ees could be described by biphasic J-shaped curves which were nearly identical before and under Fontan circulation. While above a "critical" CPP (72 +/- 9 mmHg vs. 81 +/- 8 mmHg, n.s.) the changes of CPP did not affect Ees, below this level the decrease of CPP resulted in a progressive decrease of Ees. Under Fontan circulation, the progressive increase of RAP did not influence Ees at CPP = 100 mmHg, led to a moderate decrease of Ees at CPP = 75 mmHg and severe decrease at CPP = 60 mmHg. Thus, both coronary arterial and venous pressure affect myocardial contractility after Fontan procedure.

The effects of light therapy on mini-mental state examination scores in demented patients

BACKGROUND

Preliminary evidence suggests that demented patients may experience beneficial effects of light therapy. The authors tested whether bright light therapy (BLT) is capable of improving cognitive functions in patients with Alzheimer-type dementia (AD) or vascular dementia (VD).

METHODS

Twenty-three patients with AD or VD were randomly assigned to either evening BLT or dim light therapy (DLT). Effects of light therapy on cognitive functions were assessed before and after light therapy using Mini-Mental State Examination (MMSE) scores. Body temperature rhythm (BTR) was additionally recorded pre- and posttreatment.

RESULTS

Irrespective of their diagnosis, patients treated with BLT (p =.0012) but not with DLT (p =.73) showed a statistically significant increase in MMSE total scores after light therapy. Evening BLT simultaneously induced a significant phase delay of 56 min on BTR (p =.025).

CONCLUSION

Our preliminary results suggest that short-term evening BLT may exert beneficial effects on cognitive functioning in patients with dementia.

The Ca2+-binding proteins S100A8 and S100A9 are encoded by novel injury-regulated genes

To gain insight into the molecular mechanisms underlying cutaneous wound repair, we performed a large scale screen to identify novel injury-regulated genes. Here we show a strong up-regulation of the RNA and protein levels of the two Ca(2+)-binding proteins S100A8 and S100A9 in the hyperthickened epidermis of acute murine and human wounds and of human ulcers. Furthermore, both genes were expressed by inflammatory cells in the wound. The increased expression of S100A8 and S100A9 in wound keratinocytes is most likely related to the activated state of the keratinocytes and not secondary to the inflammation of the skin, since we also found up-regulation of S100A8 and S100A9 in the epidermis of activin-overexpressing mice, which develop a hyperproliferative and abnormally differentiated epidermis in the absence of inflammation. Furthermore, S100A8 and S100A9 expression was found to be associated with partially differentiated keratinocytes in vitro. Using confocal microscopy, both proteins were shown to be at least partially associated with the keratin cytoskeleton. In addition, cultured keratinocytes efficiently secreted the S100A8/A9 dimer. These results together with previously published data suggest that S100A8 and S100A9 are novel players in wound repair, where they might be involved in the reorganization of the keratin cytoskeleton in the wounded epidermis, in the chemoattraction of inflammatory cells, and/or in the defense against microorganisms.

Downregulation of myocardial contractility via intact ventriculo--arterial coupling in the brain dead organ donor

OBJECTIVE

To test the hypothesis that altered loading conditions play a key role in hemodynamic instability and cardiac dysfunction in the brain dead (BD) organ donor.

METHODS

BD was induced by inflation of a subdural balloon catheter. In the first part of the study, left ventricular function was assessed in a canine in situ cross-circulated heart model (n=6). Pre- and afterload and coronary perfusion pressure were kept identical in all hearts throughout the experiment. In the second part of the study, hearts (n=6) were investigated in vivo allowing the interaction between left ventricular contractility and arterial load. Left ventricular pressure--volume loops were obtained by a combined conductance-pressure catheter and the slope of the endsystolic pressure--volume relationship (Ees), arterial elastance (Ea), stroke work (SW), pressure--volume area, ventriculo--arterial coupling ratio (VAC) and mechanical efficiency (Eff) were calculated.

RESULTS

Induction of BD led to a hyperdynamic response in both models with a significant increase of most hemodynamic parameters. In the in situ isolated heart model, left ventricular contractility returned to baseline without any further deterioration. In contrast, in the intact circulation the hemodynamic parameters declined significantly in comparison to baseline 4 h after BD (Ees: 4.07+/-0.51 vs. 8.06+/-1.09 mmHg/ml, P<0.05, Ea: 3.17+/-0.39 vs. 4.42+/-0.30 mmHg/ml, P<0.05). However, VAC (0.78+/-0.09 vs. 0.65+/-0.14 n.s.) and Eff (73.4+/-2.1 % vs. 76.8+/-3.7 %, n.s.) remained constant over the time.

CONCLUSION

BD induction leads to an initial hyperdynamic reaction followed by hemodynamic instability. The facts that no cardiac dysfunction occurred if loading conditions were kept constant and the ventriculo--arterial coupling ratio and mechanical efficiency remained constant in the intact animal model indicate that decreased contractility reflects to decreased arterial elastance after brain death. Therefore, reduced contractile function after brain death at a decreased afterload may contribute to stroke work optimization.

Short- and long-term results after thrombolytic treatment of deep venous thrombosis

OBJECTIVES

The goal of this study was to assess the short- and long-term efficacy of different thrombolytic therapy regimens in patients with leg or pelvic deep venous thrombosis (DVT).

BACKGROUND

It is unclear whether locoregional or systemic thrombolysis is superior in treating acute leg DVT or even whether lysis is more effective than anticoagulation therapy in preventing postthrombotic syndrome.

METHODS

A total of 250 patients averaging 40 years of age with acute DVT were randomized into five groups to receive full heparinization (1,000 IU/h) and compression treatment, with four groups also administered locoregional tissue plasminogen activator (20 mg/day) or urokinase (100,000 IU/day) or systemic streptokinase (3,000,000 IU daily) or urokinase (5,000,000 IU daily). All groups then received anticoagulation and compression treatment for one year. Primary efficacy criteria included the change after one year in the number of closed vein segments and the occurrence of postthrombotic syndrome.

RESULTS

Systemic thrombolytic therapy significantly reduced the number of closed vein segments after 12 months in patients with acute DVT compared with conventional treatment (p < 0.05). Postthrombotic syndrome also occurred with less frequency in systemically treated patients versus controls (p < 0.001). High-dose thrombolysis led to better rates of complete recanalization after seven days (p < 0.01) than locoregional lysis. However, 12 patients receiving thrombolysis (9 systemic, 3 local) suffered major bleeding complications; 9 patients on systemic treatment developed pulmonary emboli.

CONCLUSIONS

Systemic thrombolytic treatment for acute DVT achieved a significantly better short- and long-term clinical outcome than conventional heparin/anticoagulation therapy but at the expense of a serious increase in major bleeding and pulmonary emboli. Given the inherent risks for such serious complications, systemic thrombolysis, although effective, should be used selectively in limb-threatening thrombotic situations.

[Fibrinolytic, revascularizing therapy of peripheral arterial occlusive disease]

Thrombo-embolic events are the primary or secondary cause for occlusions of peripheral arteries. The systemically applied fibrinolysis rarely resulted in revascularization. The local application of plasminogen activators leads to better results. Combined with interventionally techniques 70-80% of the acute und subacute occlusions can be opened an the necessity of angio-surgical interventions can be reduced by about 50%. The technical procedure of the local fibrinolysis and the dosages of the applied activators are presently not standardized. Therefore the results of 13 reports between the years 1995-1998 including 4 prospective studies are not comparable. According to the present experiences, acute und subacute incomplete ischemia syndromes are to be seen as indication for local lysis. Especially for patients whose constitution is not optimal for surgery, local fibrinolysis is an alternative to surgical revascularization. Further studies are necessary to optimize the therapy.

Prognostic significance of tumor angiogenesis in primary fallopian tube cancer

Tumor angiogenesis has been found to be prognostically significant in many types of malignant tumors. We assessed tumor vascularity in 43 cases of histologically proven primary fallopian tube cancer, FIGO stage I-IV, using the highly specific endothelial cell marker CD34. Microvessel count was determined by counting CD34-positive cells at 200 x magnification. The 5-year disease-free survival probability was 43.8% (+/- 11.5%) in 24 patients whose tumors had a microvessel count < or = 19 microvessels/field and 19.7% (+/- 9.5%) in the > 19 microvessels/field group (P = 0.046). Stage and microvessel count were statistically significant for disease-free survival in univariate analysis. Therefore, a larger sample size would be required to detect an independent and statistically significant prognostic effect of microvessel density in primary fallopian tube cancer in multivariate analysis.

[Diagnostic imaging in staging of gynecologic carcinomas]

The prognosis in patients with gynecologic cancers depends not only on the stage but also on a wide spectrum of other findings. Cross-sectional imaging modalities, including sonography, CT and MRI, have increasingly been used for optimal treatment planning in gynecologic cancers. Their staging criteria are based on the well-established FIGO staging system. CT and MRI compete with sonography, which plays a pivotal role in the evaluation of the female pelvis. This paper reviews the role of sonography, CT and MRI in the staging of gynecologic malignancies. It puts the emphasis on MRI, which has been established as imaging modality of choice in the preoperative evaluation of cervical and endometrial cancer, and which seems slightly superior to CT in the staging of ovarian cancer.

Hemodynamic effects of double bolus reteplase versus alteplase infusion in massive pulmonary embolism

BACKGROUND

Thrombolytic agents are given in massive pulmonary embolism to dissolve or reduce the clot and normalize hemodynamics. Comparative clinical studies have shown that administration of a 2-hour infusion of alteplase is more effective than urokinase over a 12-hour period. Reteplase is a new generation thrombolytic with a longer half-life that can be administered more conveniently as a double bolus. We compared efficacy and safety of reteplase with the approved regimen of alteplase in massive pulmonary embolism.

METHODS

Thirty-six patients were enrolled and randomly assigned: 23 received reteplase and 13 received alteplase along with intravenous heparin. Reteplase was administered as 2 intravenous bolus injections of 10 U 30 minutes apart, and alteplase was administered as an intravenous infusion of a total dose of 100 mg over a 2-hour period, including an initial 10-mg bolus. Diagnosis of pulmonary embolism was confirmed by selective pulmonary angiography. Hemodynamic monitoring was conducted during the first 24 hours after administration. The primary end point was change in total pulmonary resistance. Secondary variables were pulmonary pressure, cardiac index, clinical parameters, and adverse events.

RESULTS

The primary parameter of total pulmonary resistance showed a significant decrease after just 0.5 hours in the reteplase group and after 2 hours in the alteplase group, with a further decrease persisting for up to 24 hours in both treatment groups. A similar pattern was seen in other directly measured hemodynamic parameters, especially mean pulmonary artery pressure and cardiac index; there was no significant difference between reteplase and alteplase. There was also no apparent difference between the treatment groups with respect to safety, and no stroke or intracranial hemorrhage occurred. The rate of bleedings and the incidence of nonhemorrhagic adverse events were as expected for patients with pulmonary embolism treated with a thrombolytic agent.

CONCLUSIONS

Reteplase is suitable for treatment of massive pulmonary embolism with a standard double bolus 10 + 10 U. Efficacy of reteplase appeared to be at least as good at decreasing pulmonary vascular resistance as that of the approved alteplase regimen of 100 mg infusion over a 2-hour period.

[In situ PCR and PCR in situ hybridization of paraffin-embedded tissue. New diagnostic possibilities in pathology]

In situ polymerase chain reaction (PCR) and PCR in situ hybridization are new diagnostic tools in dermatopathology. These techniques can combine the sensitivity of PCR with the advantage of in situ hybridization to localize specific cellular structures. With optical control of the PCR reaction product in these techniques, false-positive results due to contamination can be minimized. Several working protocols have been established which allow detection of DNA and RNA sequences in a rapid and reproducible manner. Two different methods have been established to detect the amplification product, the indirect PCR in situ hybridization (PCRisHyb), and the direct in situ PCR (isPCR). An easy and reproducible method for PCRisHyb and isPCR in formalin-fixed and paraffin-embedded tissue is described and the two techniques are compared. Using both isPCR and PCRisHyb, the amplification product can be visualized with an optimal morphological preservation of the tissue. Indirect PCRisHyb showed a slightly higher specificity whereas direct isPCR was the quicker, easier and less expensive method.