IL-4 instructs TH1 responses and resistance to Leishmania major in susceptible BALB/c mice

Immunity to infection with intracellular pathogens is regulated by interleukin 12 (IL-12), which mediates protective T helper type 1 (TH1) responses, or IL-4, which induces TH2 cells and susceptibility. Paradoxically, we show here that when present during the initial activation of dendritic cells (DCs) by infectious agents, IL-4 instructed DCs to produce IL-12 and promote TH1 development. This TH1 response established resistance to Leishmania major in susceptible BALB/c mice. When present later, during the period of T cell priming, IL-4 induced TH2 differentiation and progressive leishmaniasis in resistant mice. Because immune responses developed via the consecutive activation of DCs and then T cells, the contrasting effects of IL-4 on DC development and T cell differentiation led to immune responses that had opposing functional phenotypes.

Repeated low-dose treatment of rats with pilocarpine: low mortality but high proportion of rats developing epilepsy

Systemic administration of pilocarpine in rats can result in a chronic behavioral state that is similar to human temporal lobe epilepsy. The pilocarpine model of epilepsy is widely used for studying the factors that contribute to the development of epilepsy as a consequence of status epilepticus (SE). For this purpose, pilocarpine is either administered alone at a high systemic dose or in combination with lithium, which markedly potentiates the convulsant effect of pilocarpine. Both experimental protocols, however, are associated with high mortality rates. In the present study, we evaluated whether mortality rate in rats can be decreased by repeated administration of low doses of pilocarpine. The time the rats spent in SE was limited by diazepam. Preliminary experiments in lithium-free rats indicated that repeated low-dose administration of pilocarpine is too time-consuming to produce SE compared to single high-dose administration. All subsequent experiments were performed in lithium-pretreated rats. Single-dose injection of 30 mg/kg pilocarpine produced SE in approximately 70% of the animals, but 45% of the rats died although SE was interrupted by diazepam after 90 min. Repeated i.p. administration of 10 mg/kg pilocarpine at 30-min intervals resulted in SE after 2-4 injections; the mean dose of pilocarpine needed to induce SE was 26 mg/kg. When SE was interrupted after 90 min, mortality rate was below 10%, which was significantly lower compared to the protocol with one single administration of 30 mg/kg pilocarpine. In contrast to mortality rate, the development of spontaneous recurrent seizures did not differ between experimental protocols. Almost all rats which had experienced a SE of at least 60 min developed chronic epilepsy. Average latency to the first spontaneous seizure was approximately 40 days. The frequency and severity of spontaneous seizures was not significantly different between protocols, although animal groups with repeated low-dose treatment tended to have higher frequencies of spontaneous seizures compared to single-dose administration. The present study demonstrates that systemic treatment of lithium-pretreated rats with several low doses of pilocarpine efficiently produces SE and chronic epilepsy with much lower mortality rates than single-dose pilocarpine.

Myosin IB from Entamoeba histolytica is involved in phagocytosis of human erythrocytes

Entamoeba histolytica is a protozoan parasite that causes amoebic dysentery in humans. The disease is prevalent worldwide. Infection with E. histolytica results in invasion of the intestine by the parasite, followed by tissue damage and inflammation. During this invasive process, parasites kill and phagocytose human epithelial cells, immune cells and erythrocytes. Expression of amoebic pathogenicity requires a dynamic cytoskeleton that allows movement, tissue penetration and changes in parasite morphology. Myosin IB is a member of the myosin I family of motor proteins. Studies conducted both with Dictyostelium discoideum, a non-pathogenic amoeba, and with the yeast Saccharomyces cerevisiae indicate the involvement of myosin IB in cellular processes including movement, phagocytosis and endocytosis. Recently, we isolated the gene encoding myosin IB from E. histolytica. Thus, we decided to analyze the role of myosin IB in pathogenesis of amoeba. Using a specific anti-myosin IB antibody, this protein was localized in cell regions including the pseudopod, vesicles and underneath the plasma membrane. When E. histolytica was activated for erythrophagocytosis, myosin IB was markedly recruited to both the phagocytic cup and around internalized phagosomes. To analyze the role of myosin IB in phagocytosis, a strain overexpressing the myosin IB gene was constructed. This strain synthesizes threefold more myosin IB than the wild-type strain. Challenge of the transfected cell line with erythrocytes showed that these amoebae were deficient in erythrophagocytosis mainly in the uptake step, suggesting a role for myosin IB in the pathogenic activity of a human parasite.

Cytoreductive combination chemotherapy for regionally advanced unresectable extramammary Paget carcinoma

Extramammary Paget carcinoma (EPC) is considered to originate from the eccrine and apocrine glands of the adnexal skin of the axilla, vulva or penis, scrotum, or perineum. If immunohistochemical techniques with the use of cytoskeletal markers are applied in addition to histologic examination, EPC lesions are found to be multifocal adenocarcinoma of the adnexal sweat glands. So far, therapeutic approaches have included primary surgery, followed optionally by radiation therapy. It is possible to achieve a cure only when manifestations are detected early and confined regionally. The role of palliative chemotherapy has not yet been assessed in this disease, particularly because of the lack of compliance and follow-up in patients with EPC.

New insights into the role of the cytoskeleton in phagocytosis of Entamoeba histolytica

Entamoeba histolytica, a human parasite, crosses the natural barriers of the intestine and, in turn, spreads into the deeper organs, resulting in amoebiasis. The motility of the parasite and its ability to lyse or phagocytose human cells facilitates passage of the amoeba through the intestinal epithelium. Little is known about the uptake of material by this parasite; nevertheless, the cytoskeleton is believed to play a role in phagocytosis. Myosin IB, an actin-binding protein, localizes to the phagocytic cup and, with time, surrounds the internalized phagosome itself. The role of unconventional myosins in phagocytosis has also been demonstrated in other cell types, suggesting that this molecular mechanism is a common denominator in phagocytic events. Here, we summarize the emerging view of the role of unconventional myosins as well as other cytoskeleton-associated proteins in pseudopod formation at early stages of phagocytosis and during the late step of this process in E. histolytica.

A nationwide survey on bariatric surgery in Germany--results 2005-2007

BACKGROUND

Most studies on bariatric surgery outcomes are performed as clinical trials or reflect the clinical experience in single centers. The status of bariatric surgery in Germany has been examined since January 1st, 2005 with the cooperation of clinics and hospitals at the Institute of Quality Assurance in Surgery at the Otto-von-Guericke University of Magdeburg (Germany).

METHODS

In this prospective multicenter observational study, the data obtained for all primary bariatric procedures, including all repeated operations, performed on consecutive patients with morbid obesity at participating hospitals from 2005 to 2007 were prospectively collected using an Internet online data registry. In particular, perioperative characteristics, such as the spectrum of diagnostic measurements, type of surgical procedures, and short- and long-term outcomes, were investigated.

RESULTS

During the study period, 629 surgical procedures were performed at 21 hospitals in 2005, 828 procedures at 32 hospitals in 2006, and 1,666 procedures at 35 hospitals in 2007. In 2005 and 2006, gastric banding was the most frequently performed operation, followed by the Roux-en-Y gastric bypass (RYGBP). In 2007, a RYGBP was carried out in 42.1% of all bariatric procedures. Among all patients, 74.4% were female. The mean body mass index (BMI) was 48.5 kg/m(2) in 2005, 48.4 kg/m(2) in 2006, and 48.0 kg/m(2) in 2007. Follow-up data after 12 months were available for 63.8% of the patients in 2005 and 2006; these data showed greater reduction of BMI after malabsorptive rather than restrictive bariatric procedures. The mortality was 0.1% (30 days) and 0.16% (overall).

CONCLUSION

As indicated by the worldwide trend, there is an ongoing change from restrictive bariatric procedures to malabsorptive procedures and sleeve gastrectomy. Although the BMIs of German patients undergoing bariatric surgery appear to be substantially higher than those of patients from most other countries, there were no differences in intraoperative and short-term complications or in overall outcomes during follow-up when compared with published studies.

Topodermatographic image analysis for melanoma screening and the quantitative assessment of tumor dimension parameters of the skin

BACKGROUND

The clinical need to identify and evaluate changes of cutaneous lesions in melanoma screening or follow-up of patients with cancer is of paramount importance. Because skin-lesion changes may be small and numerous, clinical assessment alone does not meet the requirements of quantitative assessment. Using the computer as a diagnostic tool for the image analysis of sequentially captured skin surface images has resulted in the technical problem of insufficient registration reproducibility. This paper describes the technical logistics, setup procedure, and clinical evaluation of the novel technique termed "topodermatography," which performs the quantitative videographic image analysis of skin-lesion changes over time.

METHODS

Digitized measurements of skin-surface image parameters were performed using a high-speed processor with an onboard coprocessor, a high-resolution video camera, specifically designed image processing software, and a position framework for the adjustment of the patient's standing position. The topodermatographic image analysis was performed on 109 consecutive patients who were at risk for melanoma (N = 98), had lesions from Kaposi's sarcoma (N = 4), had metastatic skin deposits from melanoma (N = 3), and had breast cancer (N = 4).

RESULTS

Skin lesion changes over time could be identified reliably within a few millimeters of diametric enlargement. In this series, a 0.51% early melanoma detection rate was assessed in 19 of 98 patients followed for 12 months. By monitoring manifest neoplastic skin lesions, tumor growth kinetics were analyzed quantitatively to determine the total area of skin involvement, thus facilitating precise response assessment.

CONCLUSIONS

Topodermatographic image analysis helps to optimize screening and follow-up procedures for patients with melanoma and populations at risk for melanoma. In addition, metastatic tumor lesions on the skin can be monitored dynamically, facilitating the accurate evaluation of the impact of systemic therapy on multiple skin deposits from melanoma and nonmelanoma cancers.

Increased matrix proteins, collagen and transforming growth factor are early markers of hepatotoxicity in patients on long-term methotrexate therapy

BACKGROUND

Hepatotoxicity, which may lead to fibrosis and cirrhosis, often limits the use of long-term low dose methotrexate for psoriasis and autoimmune diseases. Standard light microscopy lacks sensitivity for early fibrosis.

DESIGN

This is a retrospective study of immunohistochemical markers of early fibrosis including laminin and fibronectin, collagen deposition and lipocyte activation in hepatic biopsies of 36 psoriatic patients treated with methotrexate for one to five years, at an average dose of 20 mg/week. Biopsies before initiation of methotrexate (n = 36) showed minimal immunohistochemical expression of desmin, transforming growth factor alpha, matrix proteins, and collagen. Expression of laminin, fibronectin, collagens III and IV increased significantly and progressively over baseline values after cumulative doses of 1.5 +/- 0.25 g (n = 20) and 3 +/- 0.5 g methotrexate, respectively. Increases in desmin, smooth muscle actin and collagen type I also occurred but the changes were less consistent. Light microscopic abnormalities of hepatotoxicity were not detectable in any of these biopsies.

CONCLUSIONS

Immunohistochemical quantification of matrix proteins and collagens type III and IV may be early, sensitive and dose responsive markers of methotrexate hepatotoxicity which progress with increasing cumulative doses of methotrexate.

Bcl-2 expression in rituximab refractory cutaneous B-cell lymphoma

Rituximab has been established as an effective and safe therapy for cutaneous B-cell lymphoma (CBCL). Different survival pathways, that is the Raf/MEK/Erk- or the p38MAPK cascade, have been suggested as downstream mediators of rituximab and may be involved in treatment failure. Biopsies from four patients, suffering from different subtypes of CBCL, which were obtained at various time points of relapse during or after therapy with 375 mg rituximab per m² of body surface area, were analysed for the expression of CD20, CD3, Ki-67, Raf-kinase inhibitory protein (RKIP) and bcl-2 by immunohistochemistry. No CD20-loss variants, that is the suggested main tumour escape mechanism to rituximab therapy, were observed in any specimen of relapsing CBCL. Notably, the expression of proapoptotic RKIP remained increased in these tumour samples. This was concomitated by a constant to slightly reduced proliferation status as demonstrated by Ki-67 staining. However, relapsing CBCL exhibited a strong upregulation of the antiapoptotic molecule bcl-2 in comparison to pretherapeutic levels. The immunohistochemical analyses of this case series of rituximab refractory CBCL suggest that upregulation of bcl-2 may play a major role in therapy resistance.

Evidence of thromboembolism prophylaxis in bariatric surgery-results of a quality assurance trial in bariatric surgery in Germany from 2005 to 2007 and review of the literature

BACKGROUND

Since January 1st, 2005, the current situation for bariatric surgery has been examined by means of a voluntary quality assurance study in Germany with a multicenter design in which 38 hospitals and surgical departments participated. The data are registered in cooperation with the Institute of Quality Assurance in Surgery at the Otto-von-Guericke University of Magdeburg (Germany).

METHODS

Data describing peri-interventional characteristics were prospectively documented in an internet online data registry. All primary bariatric procedures performed since January 1st, 2005, were registered. In addition, reoperations in patients who had previously undergone primary surgical intervention were included. As a representative excerpt from the overall prospective multicenter observational study on obesity surgery, data on the type, regimen, and time course of deep venous thrombosis (DVT) prophylaxis were documented. From the number and spectrum of complications, the incidences of clinically manifest DVT or pulmonary embolism (PE) were derived during the in-hospital course and follow-up in conjunction with the type of surgical procedure and body mass index (BMI).

RESULTS

Overall, 3,122 bariatric procedures were performed at 38 German hospitals between January 2005 and December 2007. These procedures were subdivided into 2,869 primary operations and 253 revisions (sex ratio, male to female = 25.6:74.4%). The average BMI of all patients was 48.5 kg/m(2) in 2005, 48.4 kg/m(2) in 2006, and 48.0 kg/m(2) in 2007. In 2005 and 2006, gastric banding (GB) was the most commonly performed operation, followed by Roux-en-Y gastric bypass (RYGBP). In 2007, RYGBP was carried out in 42.1% of all bariatric procedures. Interestingly, the incidence of deep venous thrombosis (DVT) was only 0.06%, whereas PE occurred in 0.06% of patients only after hospital discharge. The DVT prophylaxis protocol used has been changed for the last 2 years: the majority of patients with a BMI above 50 kg/m(2) received low-molecular-weight heparin twice a day.

CONCLUSION

In Germany, a trend from GB to sleeve gastrectomy (SG) and malabsorptive approach has been evaluated. This trend is associated with differences of the DVT prophylaxis regimen in the profile of bariatric surgical patients depending on BMI and the type of bariatric procedure. Despite the low incidence of DVT and pulmonary embolism (PE) detected, there is a lack of evidence on a reasonable regimen for sufficient DVT prophylaxis in bariatric surgery; instead, there are only recommendations from the guidelines and statements of a specific medical society. Therefore, prospective studies are necessary to determine the optimal DVT prophylaxis for bariatric surgical patients as well as obese patients undergoing surgery.

[Veno-occlusive syndrome with acute liver dystrophy following decarbazine therapy of malignant melanoma (author's transl)]

Case report about death due to veno-occlusive liver disease following Dacarbazine treatment: 9 years after surgical treatment of malignant melanoma of the trunk a 68-years old patient developed lymph node metastases in the right axilla, which were removed immediately by surgical excision. One month before the patient had undergone surgical treatment of empyema of the gallbladder: Cholecystectomy and appendectomy were performed, postoperative recovery was uncomplicated. On account of the second lymph node metastasis within nine months adjuvant treatment with Dacarbazine was agreed and started one month later. After having performed the first course of treatment without any hints to intolerance the patient suddenly exhibited severe shock symptoms on the fourth day of the second course. Clinically residual myocardial infarct or pulmonary embolism were assumed, but could not be verified. The patient delivered increasing hepatomegaly. A massive increase in transaminase values was noted. Hemostasiologic changes with decreased Quick value occurred. The patient died of cerebral hemorrhage five days after beginning the second Dacarbazine cycle. Autopsy findings were severe liver cell necroses as well as liver vein thromboses, no metastases of melanoma could be found. Hepatotoxicity of Dacarbazine and the mechanism of liver vein thrombosis are discussed with special regards to possible hemostasiologic changes and sensibilisation due to Dacarbazine and/or previous liver cell damage.

CD28-mediated costimulation impacts on the differentiation of DC vaccination-induced T cell responses

Costimulatory signals such as the ones elicited by CD28/B7 receptor ligation are essential for efficient T cell activation but their role in anti-tumour immune responses remains controversial. In the present study we compared the efficacy of DC vaccination-induced melanoma specific T cell responses to control the development of subcutaneous tumours and pulmonary metastases in CD28-deficient mice. Lack of CD28-mediated costimulatory signals accelerated tumour development in both model systems and also the load of pulmonary metastases was strongly increased by the end of the observation period. To scrutinize whether lack of CD28 signalling influences priming, homing or effector function of Trp-2(180-188)/K(b)-reactive T cells we investigated the characteristics of circulating and tumour infiltrating T cells. No difference in the frequency of Trp-2(180-188)/K(b)-reactive CD8+ T cells could be demonstrated among the cellular infiltrate of subcutaneous tumours after DC vaccination between both genotypes. However, the number of IFN-gamma-producing Trp-2-reactive cells was substantially lower in CD28-deficient mice and also their cytotoxicity was reduced. This suggests that CD28-mediated costimulatory signals are essential for differentiation of functional tumour-specific CD8+ T-effector cells despite having no impact on the homing of primed CD8+ T cells.

Determination of exposure due to mobile phone base stations in an epidemiological study

To investigate a supposed relationship between exposure by mobile phone base stations and wellbeing, an epidemiological cross sectional study is carried out within the German Mobile Telecommunication Research Program. In a parallel project, a method for the classification of electromagnetic exposure due to mobile phone base stations has been developed. This is based on the results of measurements of high frequency immissions in the interior of more than 1100 rooms and at outdoor locations, the calculation of the emissions of mobile phone antennas under free space propagation conditions and empirically determined transmission factors for the propagation of electromagnetic waves in different types of residential areas for passage of walls and windows. Standard tests (correlation-test, kappa-test, Bland-Altman-Plot, analysis of sensitivity and specificity) show that the method for computational exposure assessment developed in this project is applicable for a first classification of exposures due to mobile phone base stations in epidemiological studies.

PALA, vindesine, and cisplatin combination chemotherapy in advanced malignant melanoma. A pilot study

Twenty-two patients with advanced malignant melanoma were entered in a pilot study receiving combination chemotherapy with PALA, vindesine, and cisplatin (PVP). Treatment consisted of PALA 3000 mg/m2 IV on days 1 and 2, vindesine 3 mg/m2 IV on days 1 and 8, cisplatin 30 mg/m2 IV on days 1 through 5, with treatment cycles repeated on day 21 every 3 weeks. Of 22 patients, 3 had non-visceral disease confined to iuxtaregional tumor growth (Stage III), and 19 had disseminated and/or visceral disease (Stage IV). The male/female sex distribution was 13/9; median age was 45 years. All 22 patients had measurable disease; 21 were evaluable for response and toxicity. Five patients (24%) had a complete response (CR) with a median duration of 5 months, and four patients (19%) had a partial response (PR) with a median duration of 3 months. Seven patients showed disease stabilization (33%) with a median duration of 2 months. Progressive disease was seen in five patients (24%) and was commonly due to widespread visceral disease. CR could be found predominantly in non-visceral disease, whereas PR could be observed in visceral disease also. Survival time from the onset of PVP chemotherapy cannot be estimated finally, since some of the responses are continuing at the present time, and 7 of 21 patients are still alive. Currently, median survival time for responders is 8 months, and for nonresponders, 5 months. Toxicity of PVP chemotherapy is mild to moderate and allows cytotoxic drug administration on an outpatient basis. PVP chemotherapy appears to have significant activity against malignant melanoma and may therefore be an alternative regimen in the management of advanced disease. However, despite the relative high remission rate especially in non-visceral disease, response duration remains disappointingly low.

Some physico-chemical parameters that influence proteinase K resistance and the infectivity of PrP Sc after high pressure treatment

Crude brain homogenates of terminally diseased hamsters infected with the 263 K strain of scrapie (PrP Sc) were heated and/or pressurized at 800 MPa at 60 degrees C for different times (a few seconds or 5, 30, 120 min) in phosphate-buffered saline (PBS) of different pH and concentration. Prion proteins were analyzed on immunoblots for their proteinase K (PK) resistance, and in hamster bioassays for their infectivity. Samples pressurized under initially neutral conditions and containing native PrP Sc were negative on immunoblots after PK treatment, and a 6-7 log reduction of infectious units per gram was found when the samples were pressurized in PBS of pH 7.4 for 2 h. A pressure-induced change in the protein conformation of native PrP Sc may lead to less PK resistant and less infectious prions. However, opposite results were obtained after pressurizing native infectious prions at slightly acidic pH and in PBS of higher concentration. In this case an extensive fraction of native PrP Sc remained PK resistant after pressure treatment, indicating a protective effect possibly due to induced aggregation of prion proteins in such buffers.

[Experiences with high-dose cisplatin therapy in metastasized malignant melanoma]

14 patients with advanced malignant melanoma were treated in 36 therapy cycles with cisplatin. 8 patients had been pretreated with dacarbazine and 6 had received additional BCG immunotherapy. 4 patients had been irradiated after surgical removal of lymph node metastases. All patients showed significant tumor progression. 4 patients were treated showing ultimately disseminated melanoma with widespread visceral involvement. 5 patients with lymph node metastases had been operated radically and were treated postoperatively. Cisplatin was administered as a 24-h high-dose therapy (200 mg or 120-200 mg/m2) under forced mannitol diuresis, treatment cycles were repeated monthly. Of all the patients, 1 showed complete remission of supraclavicular metastases lasting for 6 months until now. 1 patient showed an initial minor response with subsequent stabilization without appearance of additional metastases for 1 year. 2 patients who had received cisplatin postoperatively showed no reappearance of tumor growth for 8 months up until now. 11 patients showed no change or progression of disease, 6 of them had received only one therapy cycle. Under clinical conditions, side effects of cisplatin treatment can be managed satisfactorily, no irreversible kidney damage could be observed under forced diuresis. As far as the above-mentioned results are concerned, antineoplastic activity of cisplatin as to advanced malignant melanoma must be considered to be of limited benefit using cisplatin as a single-agent treatment. Improvement of results might be obtained using cisplatin in a combination therapy together with other antineoplastic agents, which at the present time are being investigated in several prospective trials.

Mobil4Park: development of a sensor-stimulator network for the therapy of freezing of gait in Parkinson patients

Parkinson’s disease (PD) is one of the most common neurodegenerative diseases in the world which mainly affects the human’s motor systems. An estimated number of 7–10 million people worldwide suffer from PD. In Germany, the number of people affected by PD lies at about 300,000 and the number rises every year by approximately 13,000. One of the cardinal symptoms of PD is the freezing of gait (FoG), which arises/appears in the late stages of the PD. FoG is defined as an episodic process with increased restriction of movement or complete blockage despite the intention of moving and, as it can lead to falls and injuries and reduces the quality of life, is considered as one of the most disabling symptoms of PD. In this contribution, we introduce a wearable wireless system designed for gait monitoring and non-invasive electrical stimulation (cueing) in case of a FoG episode.

[Arterial hypertension and dementia]

Arterial hypertension (AH) is considered to be an important risk factor for vascular cognitive impairment and probably for Alzheimer's disease, too. In the current review we provide an overview of the major prospective clinical trials on this issue. With respect to the inconsistent findings of these studies one must state that the interrelations between AH and dementia are still incompletely understood. Regarding therapy there thus is a simple rule: AH should be treated until normal blood pressure values are reached. As long as the hypothesis of a J-curve between blood pressure and cognitive dysfunction has not been disproved, overaggressive blood pressure lowering cannot be recommended. Regarding the aim of preventing dementia, there is no evidence for the superiority of a specific antihypertensive treatment regimen.