[Rehabilitation, social medical evaluation and counselling in HIV-infected patients]

An inpatient rehabilitation programme for HIV-infected patients is described. Since the early nineties some 1,200 patients with HIV infection have been treated in our internal and orthopaedic rehabilitation clinic. Beside internal and orthopaedic diagnostics, supporting compliance with antiretroviral therapy, motivating the patients for regular moderate exercises and specific nutritional counselling are major issues of the programme. From the psychological point of view, the patients are offered to aquire relaxation and stress coping techniques, to take part in non-smoking courses and to use individual psychological counselling in case of depression or panic. In addition, all HIV-infected patients are offered individual advice on their disease and necessary changes in lifestyle. Finally, the programme includes social medical evaluation and counselling. As the majority of the patients are still working or are of working age, evaluating the capacity for work and potential introduction of occupational rehabilitation measures are prominent. Almost 70 percent of the HIV-infected patients who had been treated in our clinic over the last few years were fully capable of returning to their previous occupation. Our experiences demonstrate that statements such as rehabilitation of AIDS patients being useless because of its missing prospects of success, are not up-to-date any longer. Since introduction of combination antiretroviral therapy many patients with HIV infection are able to return to their previous occupation if they receive the necessary medical und psychosocial support.

Functional results and quality of life after treatment of pelvic sarcomas involving the acetabulum

BACKGROUND

Limb salvage after resection of a pelvic sarcoma that involves the acetabulum represents a surgical challenge. The ideal method of reconstruction after acetabular resection remains a subject of controversy, and the outcome in terms of the impact of therapy is still unknown. The purpose of this study was to determine the impact of surgery on health-related quality of life and function after acetabular resection.

METHODS

Eighty-one patients with a pelvic sarcoma underwent acetabular resection at a single institution. Functional evaluation and quality-of-life examination were performed in forty-five patients, and these patients comprised the study group. Quality of life was assessed with use of the European Organization for Research and Treatment of Cancer core quality-of-life questionnaire. Function was assessed with use of the Musculoskeletal Tumor Society system.

RESULTS

The median age of the patients was 30.4 years at the time of the acetabular resection and 35.7 years at the time of follow-up. The median time interval from the index operation to the latest follow-up was sixty-nine months. At the latest follow-up evaluation, the mean functional status score was 14.5 points of a maximum of 30 points. In a comparison of endoprosthetic replacement and hip transposition following resection, significantly better functional results (p = 0.017) and a lower number of complications were found in patients who had a hip transposition. Quality-of-life assessment results were also better in patients with a hip transposition, especially in role functioning (p = 0.043).

CONCLUSIONS

On the basis of the low complication rate and the good functional and quality-of-life results, hip transposition after acetabular resection seems to be the optimal technique for treating patients with a pelvic sarcoma involving the acetabulum.

Penetration of piperacillin and tazobactam into inflamed soft tissue of patients with diabetic foot infection

We investigated the pharmacokinetics of piperacillin and tazobactam in the extracellular space fluid of inflamed soft tissues of six patients with diabetic foot infection using in vivo microdialysis and found similar penetration for piperacillin but not for tazobactam into inflamed and noninflamed soft tissue.

Psychological distress among recent Russian immigrants in the United States

BACKGROUND

The purpose of this study was to examine the psychological status of Russian immigrants who have recently come to the United States.

AIMS

The project included creation of a Russian version of the Hopkins Symptom Checklist-25 (HSCL-25) in order to identify anxiety and depression in members of the Russian-speaking immigrant population.

METHODS

Translation and adaptation included (a) cross-cultural adaptation; (b) translation; (c) pre-testing; and (d) analysis of validity, reliability and internal consistency. Seventeen Russian-speaking patients at a Russian psychiatric clinic were recruited for the study and were compared with a sample of 42 Russian-speaking members of the community.

RESULTS

The instrument showed internal consistency when evaluated with coefficient alpha. Clinic patients had significantly higher anxiety and depression symptom scores than community subjects. Russian immigrants' scores on the anxiety and depression scales were less than comparative data for the United States and notably less than similar measures for Russian immigrants to Israel.

CONCLUSIONS

Recent Russian immigrants to the United States appear to have low prevalences of anxiety and depression.

Psychometric properties of a Russian version of the SF-12 Health Survey in a refugee population

This project examined psychometric properties of a Russian translation of the 12-item Short-Form health survey questionnaire (SF-12) to assess physical and mental health status in members of the Russian-speaking refugee population. Translation and adaptation included (a) cross-cultural adaptation; (b) translation; (c) pre-testing; and (d) analysis of validity, reliability, and internal consistency. Seventeen Russian-speaking patients at a Russian psychiatric clinic were recruited for the study and were compared to a sample of 42 Russian-speaking members of the community. The instrument showed internal consistency when evaluated with coefficient alpha. As compared with community subjects, clinic patients had significantly lower scores, reflecting poorer physical and mental well being.

AIDS-related progressive multifocal leukoencephalopathy in the era of HAART: report of two cases and review of the literature

Progressive multifocal leukoencephalopathy (PML) is a demyelinating disease of the central nervous system. It is caused by the JC virus (JCV), a human polyomavirus replicating in human glial cells. PML is the result of the reactivation of latent JCV infection that usually occurs in the setting of cellular immunodeficiencies such as HIV-1 infection. Epidemiologic data suggest that the impact of highly active antiretroviral therapy (HAART) on the incidence of PML is less profound than seen with other opportunistic infections. Given the lack of an effective and specific therapy for PML, HAART remains the only therapeutic option in patients with PML. However, a significant number of cases appear unresponsive to antiretroviral therapy. Moreover, there is growing data on unexpected inflammatory cases of PML after initiation of HAART. Thus, PML will remain a relevant cause of morbidity and mortality in HIV- 1-infected patients. Here we report two cases of PML, along with a concise review of the literature on this important disease.

Treatment of HIV-1-associated Kaposi's sarcoma with pegylated liposomal doxorubicin and HAART simultaneously induces effective tumor remission and CD4+ T cell recovery

BACKGROUND

The combination of highly active antiretroviral therapy (HAART) and liposomal doxorubicin is a promising approach for the treatment of progressive HIV-related Kaposi's sarcoma (KS). Here, we determined the safety, tolerability, and efficacy of liposomal doxorubicin and HAART as a combined treatment approach for advanced KS, and assessed the impact of liposomal doxorubicin on HAART-mediated immune reconstitution and viral suppression.

PATIENTS AND METHODS

In an uncontrolled observational trial, KS treatment responses were assessed in 54 HIV-1-infected patients with advanced KS according to ACTG criteria. Immunological and virological treatment responses were compared to 54 non-KS-affected HIV-1 patients who were individually matched to the study participants according to sex, age (+/- 5 years), CD4+ T cell count (+/- 25%), HIV RNA load (+/- 25%) and previous antiretroviral therapy exposure.

RESULTS

In 81.5% of the study patients, complete or partial responses were observed within a median of 8 weeks. Treatment-related side effects were predominantly confined to leukopenia (44.4% of patients) and mild-to-moderate liver enzyme elevation (22.3% of patients). Relative CD4+ T cell counts increased to a similar degree both in study patients and matched pairs (7% vs 6%, respectively), yet, absolute CD4+ T cell counts augmented considerably stronger in chemotherapy-naive matched pairs than in the study patients.

CONCLUSION

The simultaneous administration of HAART and liposomal doxorubicin is a safe and effective treatment approach for advanced KS and HAART-mediated recovery of relative CD4+ T cell counts does not seem to be impaired by concomitant treatment with liposomal doxorubicin.

Genome-wide analysis of chromosomal features repressing human immunodeficiency virus transcription

We have investigated regulatory sequences in noncoding human DNA that are associated with repression of an integrated human immunodeficiency virus type 1 (HIV-1) promoter. HIV-1 integration results in the formation of precise and homogeneous junctions between viral and host DNA, but integration takes place at many locations. Thus, the variation in HIV-1 gene expression at different integration sites reports the activity of regulatory sequences at nearby chromosomal positions. Negative regulation of HIV transcription is of particular interest because of its association with maintaining HIV in a latent state in cells from infected patients. To identify chromosomal regulators of HIV transcription, we infected Jurkat T cells with an HIV-based vector transducing green fluorescent protein (GFP) and separated cells into populations containing well-expressed (GFP-positive) or poorly expressed (GFP-negative) proviruses. We then determined the chromosomal locations of the two classes by sequencing 971 junctions between viral and cellular DNA. Possible effects of endogenous cellular transcription were characterized by transcriptional profiling. Low-level GFP expression correlated with integration in (i) gene deserts, (ii) centromeric heterochromatin, and (iii) very highly expressed cellular genes. These data provide a genome-wide picture of chromosomal features that repress transcription and suggest models for transcriptional latency in cells from HIV-infected patients.

Use of artificial skin constructs in permeation studies of clindamycin phosphate

Penetration and permeation of topically applied substances may be studied in vitro either by using excised human and animal skin or with a 3-dimensional artificial skin construct (ASC). In the present study, ASC consisting of dermal and epidermal layers were cultivated with human dermal fibroblasts and spontaneously transformed human epidermal cells from the HaCaT-cell line. For comparative purposes the permeation barrier of ASC was also evaluated using a commercial skin model (AST-2000). Higher drug permeabilities were achieved with ASC in comparison with excised human stratum corneum (EHSC). The factors between permeation coefficients of ASC and EHSC depend on the respective drugs and also on different types of the formulation. Due to higher permeation coefficients obtained, the running time of the experiments could be reduced in the case of ASC. A further advantage of ASC is the independency of skin donations. Additionally, cultivation of ASC for the use in permeation studies is possible in advance, because storage conditions under nitrogen freezing do not affect ASC quality negatively.

Treatment of acute hepatitis C infection in HIV-infected patients: a retrospective analysis of eleven cases

Studies on hepatitis C virus (HCV) monoinfected patients suggest high sustained treatment response rates of up to 98% when interferon monotherapy is administered during the acute phase of HCV-infection. To clarify whether early treatment of acute hepatitis C is similarly efficient in human immunodeficiency virus (HIV) positive patients, we conducted a retrospective survey of HIV-positive patients with acute HCV infection. Eleven HIV-positive patients who had been treated with interferon or interferon/ribavirin were identified at eight HIV-specialty outpatient clinics. The patients had been treated over a median 25 weeks with standard interferon (two patients), pegylated interferon (four patients) and pegylated interferon in combination with ribavirin (five patients). A post-treatment response (negative serum HCV-RNA at the end of treatment) was seen in 10 of 11 patients and HCV-RNA remained undetectable 24 weeks after the end of treatment in all the 10 responders. Alanine aminotransferase (ALT) normalized in eight patients while two virological responders and one nonresponder showed persistent mild ALT elevations. In conclusion, early treatment of acute hepatitis C seems to achieve high sustained virological treatment response rates also in patients with HIV-infection.

Rotationplasty type BI versus type BIIIa in children under the age of ten years

Type BI rotationplasty is currently indicated for children with tumours of the proximal femur whereas type BIIIa rotationplasty is reserved for those in which the entire femur has to be removed. Our aim was to compare these two types of rotationplasty and determine whether the knee should be preserved in children with tumours of the proximal femur. We compared the post-operative complications, oncological outcome, range of movement, Enneking score and radiographs of six children, who had undergone type BI rotationplasty with those of 12 who had undergone type BIIIa rotationplasty.

Patients with type BI rotationplasty had a mean Enneking score of 21.6 compared with 24.4 in those with type BIIIa rotationplasty, and worse mean results in all of the parameters investigated. We conclude that type BI rotationplasty has a worse functional outcome and more complications than type BIIIa rotationplasty in children under the age of ten years.

Long-term consequences of treatment interruptions in chronically HIV-1-infected patients

OBJECTIVE

To evaluate the long-term effects of antiretroviral treatment (ART) interruptions on metabolic, immunological, virological and clinical outcomes in chronically HIV-1 infected patients.

METHODS

Multi-centric, prospective, controlled 24-month cohort study in HIV-1 infected patients interrupting ART once or several times and for at least two weeks. Patients were compared to a frequency-matched control group continuing on ART.

RESULTS

A total of 399 HIV-1 infected patients were included, among them 133 patients with treatment interruption (TI) and 266 control patients. Baseline characteristics were well matched. Median baseline CD4 cell count was 379/microl in TI-patients and 410/microl in control patients (p = ns). Median duration of the first TI was 1.1 months, and 37 % of patients had two or further TI's. Whereas CD4 cell count in control patients had increased significantly by a median of 67/microl at month 24 (p<0.0001), median CD4 cell count at month 24 in the TI-patients did not differ significantly from baseline. However, two-year AIDS-free survival was not significantly different between TI- and control patients. Liver enzymes and blood lipids improved significantly during TI.

CONCLUSION

TI was associated with a significant immunological disadvantage at 24-month follow-up compared to continued ART. In this relatively immunocompetent cohort, however, TI's did not lead to an increased risk of disease progression within two years of follow-up.

Successful administration of aggressive chemotherapy concomitant to tuberculostatic and highly active antiretroviral therapy in a patient with AIDS-related Burkitt's lymphoma

Treatment of AIDS-related malignant lymphoma (ARL) remains a therapeutic challenge. There are concerns not only about infectious and haematological complications in HIV-infected patients during intensive chemotherapy, but also about potential interactions between chemotherapy and highly active antiretroviral therapy (HAART). Current data on patients treated concomitantly with intensive chemotherapy and HAART are limited, and no data exist on patients with ARL suffering from active opportunistic infections. We report the case of a 38-year-old man with advanced HIV-1 infection, pulmonary tuberculosis and Burkitt's lymphoma. Intensive chemotherapy was administered in parallel with tuberculostatic therapy and HAART. Six months later, the patient achieved not only a complete remission of Burkitt's lymphoma and sustained viral suppression, but also a full recovery from tuberculosis. This case report provides some useful observations on the successful application of intensive chemotherapy in addition to tuberculostatic therapy and HAART in HIV-infected patients.

Factors associated with emergency department visits due to acute asthma

It is important to identify characteristics related to poor disease control and frequent visits to the emergency department (ED). The objective of the present study was to compare the characteristics of patients attending the adult ED for treatment of asthma exacerbation with those attending an asthma specialist clinic (AC) in the same hospital, and to determine the factors associated with frequent visits to the ED. We conducted a cross-sectional survey of consecutive patients (12 years and older) attending the ED (N = 86) and the AC (N = 86). Significantly more ED patients than AC patients reported ED visits in the past year (95.3 vs 48.8%; P < 0.001) and had difficulty performing work (81.4 vs 49.4%; P < 0.001. Significantly more AC than ED patents had been treated with inhaled corticosteroids (75.6 vs 18.6%; P < 0.001) used to increase or start steroid therapy when an attack was perceived (46.5 vs 20.9%; P < 0.001) and correctly used a metered-dose inhaler (50.0 vs 11.6%; P < 0.001). The history of hospital admissions (odds ratio, OR, 4.00) and use of inhaled corticosteroids (OR, 0.27) were associated with frequent visits to the ED. In conclusion, ED patients were more likely than AC patients to be dependent on the acute use of the ED, were significantly less knowledgeable about asthma management and were more likely to suffer more severe disease. ED patients should be considered an important target for asthma education. Facilitating the access to ambulatory care facilities might serve to reduce asthma morbidity.

CNF and DNT

The actin cytoskeleton of mammalian cells is involved in many processes that affect the growth and colonization of bacteria, such as migration of immune cells, phagocytosis by macrophages, secretion of cytokines, maintenance of epithelial barrier functions and others. With respect to these functions, it is not surprising that many bacterial protein toxins, which are important virulence factors and causative agents of human and/or animal diseases, target the actin cytoskeleton of the host. Some toxins target actin directly, such as the C2 toxin produced by Clostridium botulinum. Moreover, bacterial toxins target the cytoskeleton indirectly by modifying actin regulators such as the low-molecular-mass guanosine triphosphate (GTP)-binding proteins of the Rho family. Remarkably, toxins affect these GTPases in a bidirectional manner. Some toxins inhibit and some activate the GTPases. Here we review the Rho-activating toxins CNF1 and CNF2 (cytotoxic necrotizing factors) from Escherichia coli, the Yersinia CNF(Y) and the dermonecrotic toxin (DNT) from Bordetella species. We describe and compare their uptake into mammalian cells, mode of action, structure-function relationship, substrate specificity and role in diseases.

Comparative pharmacology of human beta-adrenergic receptor subtypes--characterization of stably transfected receptors in CHO cells

Although many beta1-receptor antagonists and beta2-receptor agonists have been used in pharmacotherapy for many years their pharmacological properties at all three known subtypes of beta-adrenergic receptors are not always well characterized. The aim of this study was, therefore, to provide comparative binding characteristics of agonists (epinephrine, norepinephrine, isoproterenol, fenoterol, salbutamol, salmeterol, terbutalin, formoterol, broxaterol) and antagonists (propranolol, alprenolol, atenolol, metoprolol, bisoprolol, carvedilol, pindolol, BRL 37344, CGP 20712, SR 59230A, CGP 12177, ICI 118551) at all three subtypes of human beta-adrenergic receptors in an identical cellular background. We generated Chinese hamster ovary (CHO) cells stably expressing the three beta-adrenergic receptor subtypes at comparable levels. We characterized these receptor subtypes and analyzed the affinity of routinely used drugs as well as experimental compounds in competition binding studies, using the non-selective antagonist 125I-cyanopindolol as a radioligand. Furthermore, we analyzed the beta-receptor-mediated adenylyl cyclase activity in isolated membranes from these cell lines. The results from our experiments show that all compounds exhibit distinct patterns of selectivity and activity at the three beta-receptor subtypes. In particular, a number of beta2- or beta3-receptor agonists that are inverse agonists at the other subtypes were identified. In addition, beta1-receptor antagonists with agonistic activity at beta2- and beta3-receptors were found. These specific mixtures of agonism, antagonism, and inverse agonism at different subtypes may have important implications for the therapeutic use of the respective compounds.

Adenosine-induced cell death: evidence for receptor-mediated signalling

Adenosine modulates the proliferation, survival and apoptosis of many different cell types, ranging from epithelial, endothelial and smooth muscle cells, to cells of the immune and neural lineages. In this review, we critically discuss the available in vitro and in vivo data which support a role for adenosine in both development-associated apoptosis, and in diseases characterized by either pathologically increased cell death (e.g., ischemia, trauma and aging-associated neurodegeneration) or abnormally reduced spontaneous apoptosis (e.g., cancer). Particular emphasis is given to the possible role of extracellular adenosine receptors, since these may represent novel and attractive molecular targets for the pharmacological modulation of apoptosis. In some instances, adenosine-induced cell death has been demonstrated to require entry of the nucleoside inside cells; however, in many other cases, activation of specific adenosine extracellular receptors has been demonstrated. Of the four G protein-coupled adenosine receptors so far identified, the A2A and the A3 receptors have been specifically implicated in modulation of cell death. For the A3 receptor, results obtained by exposing both cardiomyocytes and brain astrocytes to graded concentrations of selective agonists suggest induction of both cell protection and cell death. Such opposite effects, which likely depend on the degree of receptor activation, may have important therapeutic implications in the pharmacological modulation of cardiac and brain ischemia. For the A2A receptor, recent intriguing data suggest a specific role in immune cell death and immunosuppression, which may be relevant to both adenosine-deaminase-immunodeficiency syndrome (a pathology characterized by accumulation of adenosine to toxic levels) and in tumors where induction of apoptosis via activation of specific extracellular receptors may be desirable. Finally, preliminary data suggest that, in a similar way to the adenosine-deaminase-immunodeficiency syndrome, the abnormal accumulation of adenosine in degenerative muscular diseases may contribute to muscle cell death. Although the role of adenosine receptors in this effect still remains to be determined, these data suggest that adenosine-induced apoptosis may also represent a novel pathogenic pathway in muscular dystrophies.

Tumors of the pelvis: complications after reconstruction

INTRODUCTION

Complications after pelvic sarcoma surgery are frequent; however, the reports on complications are limited. Results of the authors' experience with 110 primary pelvic tumor resections and methods to achieve low complication rates for pelvic reconstruction are reported.

MATERIALS AND METHODS

From 1982 to 1996, 110 patients with pelvic sarcoma (42 Ewing sarcomas, 40 chondrosarcomas, 21 osteosarcomas, and 7 other malignant tumors) underwent surgery. Sixteen patients underwent implantation of a hemipelvic megaprosthesis, 13 patients had implantation of an allograft for sacroiliac arthrodesis, 12 patients had implantation of an autograft for sacroiliac arthrodesis, and 17 patients underwent hip transposition. There were 9 hindquarter amputations, 6 implantations of allograft and total hip endoprosthesis, 1 implantation of prosthesis with autograft, and 1 implantation of allograft and autograft. No skeletal reconstruction was done in 35 patients.

RESULTS

Postoperative function was as follows: 37% in patients with prosthesis, 60% in allograft, 66% in autograft, 66% in hip transposition, 37% in amputation, and 79% without reconstruction. In total, 10/16 patients with prosthetic replacement, 9/13 with allograft implantation, 4/12 with autograft implantation, 7/17 with hip transposition, 5/9 with amputation, 6/6 with prosthesis and allograft, and 12/35 without skeletal reconstruction had complications. Frequent complications depending on the reconstruction were infection in 6/10 prostheses and in 5/13 allografts, leg length discrepancy in 2/12 autografts and 4/17 hip transpositions, hematoma in 3/9 amputations, and infection (6) and skin problems (5) in 6 prostheses with allograft.

CONCLUSION

Because of the small number of complications and good function, autograft implantation after iliac resection and hip transposition after acetabular resection are advisable.

Progressive multifocal leucoencephalopathy with unusual inflammatory response during antiretroviral treatment

A case of biopsy verified progressive multifocal leucoencephalopathy (PML) in an HIV patient is presented. Imaging and histological examination confirmed remarkable inflammatory activity accompanied by an unusually benign clinical course despite no clear evidence of immune reconstitution after the start of antiretroviral treatment. This case not only raises several questions regarding the pathophysiology of PML, but gives also evidence that AIDS associated inflammatory PML must be considered another clinical entity in the expanding range of diseases now commonly referred to as the immune reconstitution syndrome.

Influence of amplitude modulated noise on the recognition of communication signals in the grasshopper Chorthippus biguttulus

The detection of acoustic communication signals in the presence of sinusoidally amplitude modulated noise was investigated in males of the grasshopper Chorthippus biguttulus. The auditory system of grasshoppers exhibits only poor spectral resolution. Hence, these animals are ideally suited to investigate noise tolerance in a system operating in the temporal domain. As a sensitive indicator for signal recognition the conspicuous phonotactic turning responses of males were recorded. The main result was that noise modulated at low frequencies (1.5-5 Hz) did not impair recognition compared to a unmodulated noise. With long stimuli even a moderate improvement of noise tolerance was observed, an effect that can probably be attributed to the existence of long troughs at low modulation frequencies during which the masking of the signal was reduced. Higher modulation frequencies (15-150 Hz), however, rendered detection and recognition increasingly difficult, due to a strong interference of the sound pulses of the masking noise with the syllable-pause structure of the species-specific signals. There are no indications for the operation of mechanisms analogous to comodulation masking release as found in vertebrates, nor for a spatial release from masking.

Titer determination of Ad5 in blood: a cautionary note

Recombinant adenoviruses are presently the most efficient in vivo gene transfer system available. Targeting single organs or large tumors by adenoviral vectors requires an intravascular route of application. During the first pass of viral particles through the vascular bed of the target tissue, virus uptake is not quantitative and indefinite amounts of particles leak into circulation. To determine the amount of leaking particles and to calculate organ-specific uptake (in-/outflow ratio), it is necessary to titrate virus particles directly in blood. In preclinical and clinical trials titration is currently mostly done with blood plasma instead of full blood. However, this technique provides valid results only as long as there is no affinity between adenovirus particles and erythrocytes. In this study we demonstrate that Ad5 particles, as mostly employed for gene therapy, have a strong affinity to human erythrocytes. At 60 min after coincubation of human erythrocytes and Ad5 particles, more than 98% of the particles are attached to the surface of erythrocytes. Therefore, ignoring the amount of red cell bound particles by performing titration in plasma leads to severe miscalculation of organ-specific transfer rates or virus circulation half-life. The biological impact of an increased affinity between virus particles and erythrocytes will be discussed.

Combination ecotoxicity and testing of common chemical discharges to sewer using the Vibrio fischeri luminescence bioassay

In order to investigate possible synergistic or antagonistic (more or less than additive) toxicity effects, mixtures of chemicals were tested in water using a microbial bioassay. Ten toxicants (3,4-dichloroaniline, 3,5-dichlorophenol, cadmium, chromium, copper, Lindane, linear alkylbenzene sulphonate, pentachlorophenol, toluene, zinc) were chosen on the basis of their common occurrence in industrial effluents within local waste water treatment plants. These toxicants also cover a wide range of modes of toxic action, namely, polar and non-polar narcosis, membrane disruption, respiratory disruption, uncouplers of oxidative phosphorylation, biochemical disruption and enzyme inhibition. Efficient screening for possible combination toxicity between toxicants involved testing the chemicals both singly and in triplet combinations. The triplets were based on four replicates of a balanced incomplete block design (BIB). A standardised Vibrio fischeri rapid toxicity bioluminescence assay was used. The combinations tested showed that only one mixture was found to be significantly more toxic than expected from the pure single-toxicant results. Two triplets were significantly less toxic. Further tests on the more toxic triplet showed that the effect was due to only one of the 45 pairs originally screened. It is concluded that synergistic effects in combinations of toxicants are rather rare in bioluminescence systems utilising common effluents discharged to sewer.

Doubled full shot noise in quantum coherent superconductor-semiconductor junctions

We performed low temperature shot noise measurements in superconductor (TiN) strongly disordered normal metal (heavily doped Si) weakly transparent junctions. We show that the conductance has a maximum due to coherent multiple Andreev reflections at low energy and that the shot noise is then twice the Poisson noise (S = 4eI). When the subgap conductance reaches its minimum at finite voltage the shot noise changes to the normal value (S = 2eI) due to a large quasiparticle contribution.

[Options for surgical treatment of malignant bone tumors]

Beside the susceptibility to a (neo-) adjuvant therapy, the surgical margin is the most important prognostic factor in the treatment of primary malignant bone tumors. If adjuvant therapy is not possible, the outcome of the disease depends on the selected surgical treatment. Limb salvage has proven to be a safe procedure for local tumor control and provides good functional results. The surgeon has to consider the best surgical option depending on the site and size of the tumor but also depending on the patient's age and the overall prognosis. Surgical techniques and possible complications of the most common procedures in tumor surgery are described.

[Childhood diseases, infectious diseases, and fever as potential risk factors for cancer?]

OBJECTIVE

We investigated the assertion that past childhood diseases, acute and febrile infections as well as allergies have a preventive effect on cancer. Former studies on this topic show controversial results and methodical deficits. PATIENTS AND METHODS The investigation was conducted as a retrospective case control study with 111 cancer patients and a group of 109 control persons from 3 hospitals in Berlin.

RESULTS

A significant change in the risk of developing cancer could only be observed for mumps (OR = 2.6; increased risk), whooping cough (OR = 2.7; increased risk), and colds in the recent past (OR = 0.7; decreased risk). Fever within the last 5 years showed no association with the development of malign tumors.

CONCLUSION

We could not confirm the results of former studies which assumed a preventive effect of childhood diseases and fever on the cancer risk. On the contrary, on the basis of this investigation one might postulate a 2- to 3-fold rise of the cancer risk by mumps or whooping cough. Because of divergent study results, deficits in the study designs, and a low evidence of the present findings no final statement on the association between childhood diseases or fever and cancer should be made.

HHV-8 DNA in blood and the development of HIV-associated Kaposi's sarcoma in the era of HAART--a prospective evaluation

OBJECTIVE

To explore the significance of HHV-8 viremia in HIV-positive individuals for the risk of developing Kaposi's sarcoma (KS) in the era of highly active antiretroviral therapy.

METHODS

237 HIV-positive patients were included in this prospective evaluation and followed over an average duration of 34 months. HHV-8 DNA in peripheral blood mononuclear cells (PBMCs) and CD4-lymphocytes were determined. In addition AIDS-defining conditions and antiretroviral therapy were documented of all participating subjects.

RESULTS

HHV-8 DNA was detectable in PBMCs of 12.6% out of all individuals. 53.3% of these patients initially complained about KS, although 9.2% of patients without HHV-8 DNA in PBMCs were found on KS as well. Furthermore, four patients in total were observed with newly developed KS during follow up visits. None of these patients were noted with detectable HHV-8 DNA at their initial evaluation.

CONCLUSIONS

Prevalence of HHV-8 DNA in PBMCs of subjects in this investigation was quite similar to former investigations. However, new diagnosed KS occurred less frequently than demonstrated in previous studies. All of those observed patients with new KS manifestations were negative for HHV-8 DNA in PBMCs at study entry. This observation differs from earlier studies which have postulated the detection of HHV-8 DNA in PBMCs as a predictive value for development of KS. Due to results as presented, a single HHV-8 DNA test in blood has no predictive value in support of predictability of KS development. With respect toto costs and to a less complicated performance antibody assays should be preferred.

Validation of questionnaires from several medical fields regarding the constitution of patients

INTRODUCTION

To consider or determine an individual's 'warm and cold' constitution is common part of traditional Chinese medicine (TCM), Indian medicine (Ayurveda), anthroposophic medicine and classical natural medicine.

OBJECTIVE

Common psychometric characteristics of 4 questionnaires should be examined.

METHODS

110 cancer patients and 110 non-cancer patients were asked to answer these questionnaires twice 4 weeks apart. Subsequent validation of the questionnaires included psychometrical qualities of item acceptability, sensitivity to change, construct validity (homogeneity), re-test reliability and group comparison.

RESULTS

The Ayurveda questionnaire was considered suitable after reducing the questions from 22 to 8 (internal construct validity kappa = 0.64). The TCM questionnaire was considered unsuitable in our model because of the absence of construct validity. The questionnaire on anthroposophic medicine was considered a suitable and reliable tool with alpha = 0.57 (Cronbach's alpha) and r = 0.61 (re-test reliability) after reducing the questions from 6 to 4. The questionnaire on sensitivity to temperatures based on classical natural medicine was considered suitable after reducing the questions from 10 to 8 (alpha = 0.58; r = 0.73). Cancer and non-cancer patients differ in only one item, i.e. in their sensitivities to cold.

CONCLUSION

The questionnaires for anthroposophic medicine, Ayurveda medicine and sensitivity to temperatures are in part suitable and reliable for determining individual constitutions according to their medical philosophy. The questionnaire based on traditional Chinese medicine failed these criteria. A difference between patients with or without malignant disease was only observed for sensitivity to temperatures. The anthroposophic hypothesis that cancer either changes an individual's thermic constitution or is caused by such a change could not be confirmed in this study.

Differential mitogenic responses of human macrovascular and microvascular endothelial cells to cytokines underline their phenotypic heterogeneity

A variety of growth factors promote the complex multistep process of angiogenesis. The mitogenic activity of vascular endothelial growth factors (VEGFs) and placental growth factors (PlGFs), known as cytokines acting predominantly on endothelial cells, was tested on human umbilical vein endothelial cells (HUVEC) and microvascular endothelial cells (MIEC) and compared with the potency of the universally acting basic fibroblast growth factor (FGF-2). The cells were seeded at different cell numbers and incubated with various doses of growth factors for a period of 24-72 h in culture medium +/- serum. Proliferation was determined by measuring the optical density after staining the cells with the tetrazolium salt WST-1. VEGF121 and VEGF165 increased the number of HUVEC and MIEC at low and high seeding densities various doses and incubation times. The efficiency of FGF-2 was less pronounced at high seeding densities of the cells under serum-free conditions. PlGF-1 and PlGF-2 stimulated mitogenesis on HUVEC only at low cell numbers and after a short incubation time by 125 +/- 3% and 102 +/- 5% (P < 0.001), respectively. Longer incubation times with the lower seeding density in the absence of FCS did not induce a significant stimulatory effect of the PlGFs. MIEC responded stronger to all growth factors. In particular under serum free conditions, PlGF-1 and PlGF-2 effectively stimulated cell proliferation by 247 +/- 54% (P < 0.01) and 288 +/- 40% (P < 0.05) at low cell numbers, and by 81 +/- 13% (P < 0.05) and 49 +/- 13% (P < 0.01), respectively, at high cell numbers. The addition of fetal calf serum caused a reduced proliferative response of all growth factors on both cell types related to the controls. In conclusion, MIEC and HUVEC differ in their proliferative response to VEGFs, PlGFs and FGF-2.

Soft tissue reconstruction of megaprostheses using a trevira tube

In soft tissue reconstruction of megaprostheses, the reattachment of soft tissue and joint capsules is essential. Sixty-nine megaprostheses were implanted and a trevira tube was applied to support reconstruction of the capsule and soft tissue. In cases of proximal femur replacement (33 patients), total femur replacement (five patients), and proximal humerus replacement (16 patients), the trevira tube allowed for reconstruction of the capsule and refixation of the muscles and helped to minimize dislocation. In cases of proximal tibia replacement (seven patients), arthrodesis of the knee (three patients), total knee replacement (two patients), and distal femur replacement (three patients), the trevira tube allowed for attachment of muscle flaps and extensor apparatus. Dislocation was observed in two of 54 patients who had proximal femur replacements. No dislocation was observed in patients with a total femur endoprosthesis or a proximal humerus endoprosthesis. The trevira tube also was used to attach the gastrocnemius muscle in patients with a proximal tibia endoprosthesis and to reattach the rotator cuff in patients with a proximal humerus prosthesis. There was no significant increase in the rate of infection. The histopathologic findings in six patients showed tissue ingrowth into the tube.

Survival of AIDS patients with primary central nervous system lymphoma is dramatically improved by HAART-induced immune recovery

OBJECTIVE

To evaluate the impact of immune recovery induced by highly active antiretroviral therapy (HAART) on the survival of AIDS patients with primary central nervous system lymphoma (PCNSL).

METHODS

In a multicentric retrospective analysis, 29 HIV-infected patients with histologically confirmed PCNSL were identified. To evaluate median survival, Kaplan-Meier statistics were used. To explore the effects of different variables on survival, a Weibull accelerated failure time regression analysis was performed.

RESULTS

Median age at manifestation of PCNSL was 39.1 years and median CD4 cell count was 11 x 10(6) cells/l. Seventy per cent of the patients had had a prior AIDS-defining illness. Cranial radiation (CR) was given to 12 out of 29 patients. Six patients were treated with HAART. Survival time of these patients and of the patients treated with CR alone differed significantly from those receiving neither CR nor HAART (median Kaplan-Meier survival estimate: 1093, 132, and 33 days, respectively). In the multivariate regression model, HAART and CR were identified as the only variables independently associated with prolonged survival. HAART versus no HAART and CR versus no CR increased the time to event by a factor of 6.1 (95% confidence interval, 2.4-16.0; P = 0.0002) and 3.1 (95% confidence interval, 1.5-6.3; P = 0.002), respectively. Four out of six patients on HAART showed a marked immune recovery and survived for more than 1.5 years, with two patients still alive.

CONCLUSION

Data from this cohort indicate that immune recovery induced by HAART leads to dramatic improvement in survival of patients with AIDS-associated PCNSL. These findings may have important implications for future treatment strategies.

Cardiology and AIDS--HAART and the consequences

Since the introduction of highly active antiretroviral therapy (HAART), AIDS has become a treatable disease. A steep decline in morbidity and mortality has been observed in most western countries. The HIV epidemic is now moving into middle-aged populations which are already at increased risk for cardiovascular disease. Since the cardiovascular system is frequently affected in HIV infection, reflections on traditional cardiovascular risk factors is a pressing issue. Moreover, during the last few years, complex lipodystrophic body changes in association with metabolic abnormalities such as dyslipidemia and insulin resistance have become a common feature in HIV+ patients on HAART. Although the precise mechanisms are not fully understood, early reports on myocardial infarctions and vascular changes have raised concern about the possibility of an epidemic of cardiovascular events among HAART patients within the next decade. Not only more data on lipid-lowering drugs in the context of HAART, on switching strategies, and treatment interruptions, but also from intervention studies on traditional risk factors such as smoking, are urgently needed. In this review the key issues concerning cardiovascular aspects of HIV infection in the era of HAART and possible preventive strategies are discussed.

Genetic imbalances revealed by comparative genomic hybridization in Ewing tumors

Ewing tumors are characterized by reciprocal translocations involving the EWS gene on 22q12 fused to ETS transcription-factor family members. Little is known about further aberrations contributing to tumor development and progression. Sixty-two frozen tumors with known EWS rearrangements (52 primary tumors, 10 relapses) of ET patients registered in the EICESS protocol were analyzed by comparative genomic hybridization (CGH). The median number of changes in 52 primary and 10 relapsed cases was 2.5 and 5.0 per tumor (P = 0.153). Frequent abnormalities included gains of chromosomes 8, 12, 20, and 1q and losses of 16q and 19q. Neither number nor type of aberration was associated with histology, tumor size, disease stage, tumor localization, or histologic tumor response to chemotherapy. Among the 52 primary tumors, 26 with Type I fusion (EWS exon 7 to FLI1 exon 6) and 26 with other fusion types had a median of 2.0 and 3.0 aberrations per tumor, respectively (P = 0.031). Combinations of gains of chromosomes 8 and 12, gains of chromosome 20, and either gains of 8q or 18q and losses of 16q and 17p frequently occurred. The cumulative overall survival (OAS) was different between 35 patients with <5 aberrations and 13 patients with > or =5 aberrations (P = 0.009). Univariate analysis showed that patients with gains of 1q, 2q, 12, and 20 or losses of 16q and 17p had significantly lower OAS than those without aberrations. By multivariate analysis, loss of 16q (relative risk [RR] = 5.3; P = 0.0006) was an independent prognostic factor.

Testing the toxicity of influents to activated sludge plants with the Vibrio fischeri bioassay utilising a sludge matrix

To protect the bioceonosis within activated sludge, a method of predicting the toxic effect of influents to the biological treatment stage of waste water treatment plants, based on DIN method 38412 L 34, has been developed. A population of the luminescent marine bacterium Vibrio fischeri was incorporated into a sludge testing matrix derived from a model laboratory and real activated sludge plants. The sludge was challenged with different concentrations of pure toxicants and complex aqueous samples, and light output by V. fischeri monitored. The results were compared to toxicant testing in the absence of sludge (standard test). The modified method was found to be less sensitive for some toxicants tested than the standard DIN and other bioluminescent tests, but considered more realistic as it provides buffering and takes into account sorption which can affect the sensitivity of the test towards some compounds. The method is comparable in terms of ease of use, speed, reproducibility and cost effectiveness to standard V. fischeri luminescence methods.

Structurally related nucleotides as selective agonists and antagonists at P2Y1 receptors

The P2Y1 receptor responds to adenine nucleotides and is present in platelets, heart, smooth muscles prostate, ovary, and brain. A selective antagonist may be useful as an antithrombotic agent. We have analyzed the binding site of this G protein-coupled receptor using ligand design, site-directed mutagenesis, and homology modeling based on rhodopsin. We have designed and synthesized a series of deoxyadenosine 3',5'-bisphosphate derivatives that act as antagonists, or, in some cases with small structural changes, as agonists or partial agonists. The 2-position accommodates Cl or thioethers, whereas the N6-position is limited to Me or Et. 2'-Substitution with OH or OMe increases agonist efficacy over 2'-H. Using molecular modeling of the binding site, the oxygen atoms of the ribose moiety were predicted to be non-essential, i.e. no specific H-bonds with the receptor protein appear in the model. We have, therefore, substituted this moiety with carbocylics, smaller and larger rings, conformationally constrained rings, and acyclics, with retention of affinity for the receptor. With simplified pharmacophores we are exploring the steric and electronic requirements of the receptor binding site, and the structural basis of receptor activation.

Rotationplasty--surgical treatment modality after failed limb salvage procedure

Twelve patients aged between 10.9 and 64.7 (mean 28.5) years with a malignant tumour of the knee region underwent a rotationplasty after failed primary limb salvage procedure. The reasons for failure which finally lead to surgery were recurrent infection in 10 patients and local recurrence of the tumour in 2. The number of operations before the rotationplasty was performed was between 2 and 23 (mean 6.7). According to the primary tumour site, 9 patients underwent a rotationplasty type A1, 3 patients type A2, and 1 patient type BII. In 9 patients the rotationplasty was successful, but 3 patients finally had to undergo amputation. Intraoperative preservation of the vessels was difficult in these 3 patients due to infection and oedema of the arteries or massive fibrous tissues after the previous surgery. After rotationplasty, 3 of 9 patients had to undergo additional surgery because of thrombosis, pseudarthrosis and infection (n = 5, range 1-2). The mean follow-up after rotationplasty was 34.9 (range 13-65) months. The mean functional status according to the MSTS criteria in patients after rotationplasty scored 21.3 of 30 points. In the group of amputees, the score was 19 (range 16-22). Concerning the health-related quality-of-life, the mean score in physical functioning was 76.3 in the group with a rotationplasty versus 50.0 in the group of amputees. Patients with a rotationplasty reached a higher score of global health status (77.1 vs 58.3). Based on the present results we are convinced that rotationplasty can be recommended as a treatment option after a failed limb salvage procedure.

The PlA1/A2 polymorphism of platelet glycoprotein IIIa is not associated with deep venous thrombosis

BACKGROUND

Platelet glycoprotein (GP) IIb/IIIa, a fibrinogen and von Willebrand factor binding membrane receptor, has an important role in platelet aggregation. A common leucine33-proline polymorphism (PlA1/A2) of the gene encoding the GP IIIa subunit is associated with platelet reactivity and has been proposed as a risk factor for atherothrombotic disease. The aim of this study was to investigate the role of this polymorphism for deep venous thrombosis (DVT).

METHODS

We performed a case-control study including 206 patients with documented DVT and a sex- and age-matched group of 310 control subjects. GP IIIa genotypes were determined by restriction fragment analysis of amplimers containing the polymorphic site.

RESULTS

A1/A1, A1/A2 and A2/A2 genotypes were found in 67.0, 31.6 and 1.5 percent of patients and 72.3, 25.8 and 1.9 percent of controls (p=0.35), PlA2 allele frequencies were 0.17 in patients and 0.15 in controls (p=0.92). Odds ratio of the PlA2 allele for DVT was 1.21 (95 percent CI 0.85-1.71, p=0.29) and remained insignificant after adjustment for factor V Leiden and prothrombin 20210A genotypes (1.22, 95 percent CI 0.86-1.75, p=0.27).

CONCLUSIONS

Our data suggest that the PlA1/A2 polymorphism of GP IIIa is not associated with DVT.

[Ablative and extremity salvage tumor surgery of the lower extremity--a 10 year comparison]

AIM

The treatment of choice for local tumor control was amputation in the 1970's. Nowadays, limb salvage procedures have become the new standard, implicating that limb salvage surgery results in a better quality of life. This study attempts to prove this hypothesis.

METHOD

In total, 102 patients who survived longer than ten years after tumor treatment of the lower extremities were investigated, of these, 71 patients underwent ablative procedures compared to 31 patients with limb salvage surgery. Operative revisions, education level, and occupational situation were evaluated in both groups. To analyze the outcome of every patient regarding functional results, quality of life, life contentment, and social parameters, the functional evaluation system of the Muskulo-Skeletal-Tumor Society (MSTS), the Freiburger Life-Contentment-Questionnaire (FLZ) and the Quality of Life Questionnaire (QLQ-C-30) of the European Organization of Research and treatment of Cancer (EORTC) were used.

RESULTS

Patients treated with a limb salvage procedure underwent more surgical revisions (p < 0.000). Educational level and occupational situation showed no difference in both groups. Functional results reached similar levels in both groups (74.6% vs. 73.8%). Life contentment and Quality of Life measurements showed good results in both groups. The FLZ-questionnaire showed significantly better results for the ablative group in some items.

CONCLUSION

The type of surgical local therapy of lower extremity tumors has no measurable effect on quality of life according to long-term follow-up in lower extremity tumors. In cases with a risk of inadequate margins when performing limb salvage surgery, an ablative procedure should be preferred.