[Robot-assisted minimally invasive lobectomy with systematic lymphadenectomy for lung cancer]. / Roboterassistierte minimalinvasive Lobektomie mit systematischer Lymphadenektomie zur Behandlung des Bronchialkarzinoms.

BACKGROUND AND INTRODUCTION: Lobectomy for lung cancer is the standard therapy for lung cancer in limited stages. The adoption of minimally invasive lobectomy (video-assisted thoracic surgery or VATS lobectomy) has increased worldwide since its first description more than 15 years ago. However, the VATS technique has a long learning curve and sometimes limitations in terms of precise preparation and presentability of the central structures of the lung hilus due to the limited mobility of the standard thoracoscopic instruments. By using a four-arm robotic platform (DaVinci®), not only the preparation of the hilus structures but also the central lymphadenectomy can be performed in a comfortable and safe way under a clear and precise view. INDICATION: Surgical treatment of locally limited lung cancer in the right lower lobe (squamous cell carcinoma). PROCEDURE: Robot-assisted, minimally invasive right lower lobectomy with systematic lymphadenectomy. CONCLUSION: Robot-assisted minimal invasive lobectomy is feasible with special regard to oncological and technical aspects. Especially the intrathoracic precise dissection of the tissue under a perfect view allow a comfortable and safe operation technique.

Role of negative regulation in promoter specificity of the homologous transcriptional activators Ace2p and Swi5p.

The Ace2p and Swi5p zinc finger proteins have nearly identical DNA-binding domains, yet in vivo they activate transcription of different genes, CTS1 and HO. We now demonstrate that Ace2p and Swi5p recognize sites in the CTS1 and HO promoters with the same affinities, raising the question of how promoter specificity is achieved by these proteins with similar DNA-binding domains. It has been previously shown that Swi5p binds to the HO promoter cooperatively with the Pho2p (Base2p/Grf10p) homeodomain protein, and we now show that Ace2p does not interact with Pho2p. Analysis of CTS1 promoter fragments inserted into a heterologous promoter identify a sequence 90 bp away from the Ace2p binding sites which is required to prevent activation by Swi5p through these binding sites. These results suggest that a regulatory protein bound to the CTS1 promoter is needed to prevent Swi5p from activating CT1S expression. A genetic screen was conducted to identify suppressor mutations which allow CTS1 expression in the absence of the Ace2p activator. The nce3 mutation suppresses the ace2 defect in CTS1 expression only if the strain contains a functional SWI5 gene, suggesting that NCE3 normally functions to prevent Swi5p from activating CTS1. The role of negative regulators such as NCE3, as well as the previously described SIN5 gene, in determining the promoter specificity of homologous activators is discussed.

[Coagulation and formation of malignant effusions]. / Die Rolle des Gerinnungssystems bei der Entstehung maligner Ergüsse.

Malignant effusions are a frequent problem for cancer patients. Due to the high resistance of tumor cells within these effusions, no effective treatment has been defined yet. Most patients exhibit additional phenomena related to hyper-coagulability such as elevated levels for d-dimers and prothrombin fragments f1.2; half of them suffer from manifest thrombosis or complications. We followed the hypothesis that the activated coagulation system contributes to the resistance of tumor cells and analyzed the effusions from cancer patients. The majority of isolated tumor cells aberrantly expressed PAR-1 thrombin receptors. In vitro pre-incubation of PAR-1 expressing human leukemia cells with thrombin resulted in a dose-dependent resistance to idarubicin. Within the effusions, we did not only find high concentrations of VEGF and tissue factor, but also all coagulation factors of the tissue factor pathway. Very high levels of prothrombin fragments f1.2 indicate constant thrombin generation. Upon the basis of these findings, we developed a multistep model elucidating the pathophysiological generation of malignant effusions, which might serve as a basis for further examinations.

Genetic and physical interactions between yeast RGR1 and SIN4 in chromatin organization and transcriptional regulation.

The SIN4 and RGR1 genes of Saccharomyces cerevisiae were identified by mutations in quite different genetic screens. We have shown that the SIN4 gene product is required for proper transcriptional regulation of many genes and that a sin4 mutation can affect either activation or repression of specific genes. We have suggested that this dual nature of SIN4 in transcriptional regulation is due to its involvement in chromatin organization. We now report that the role of RGR1 in gene regulation is similar to that of SIN4. SIN4 and RGR1 both function as negative transcriptional regulators of HO and IME1, and mutations in either gene lead to decreased expression of other genes including CTS1. Strains with sin4 or rgr1 mutations both have phenotypes similar to those caused by histone mutations, including suppression of delta insertion into promoters (Spt- phenotype), activation of promoters lacking UAS elements, and decreased superhelical density of plasmid DNA molecules. Overexpression of RGR1 suppresses the temperature sensitivity due to a sin4 mutation. Finally, we use yeast strains expressing GST fusion proteins to demonstrate that the Sin4p and Rgr1p proteins are physically associated in vivo. These results indicate that Sin4p and Rgr1p act together in vivo to organize chromatin structure and thus regulate transcription.

RAD53 regulates DBF4 independently of checkpoint function in Saccharomyces cerevisiae.

The Cdc7p and Dbf4p proteins form an active kinase complex in Saccharomyces cerevisiae that is essential for the initiation of DNA replication. A genetic screen for mutations that are lethal in combination with cdc7-1 led to the isolation of seven lsd (lethal with seven defect) complementation groups. The lsd7 complementation group contained two temperature-sensitive dbf4 alleles. The lsd1 complementation group contained a new allele of RAD53, which was designated rad53-31. RAD53 encodes an essential protein kinase that is required for the activation of DNA damage and DNA replication checkpoint pathways, and that is implicated as a positive regulator of S phase. Unlike other RAD53 alleles, we demonstrate that the rad53-31 allele retains an intact checkpoint function. Thus, the checkpoint function and the DNA replication function of RAD53 can be functionally separated. The activation of DNA replication through RAD53 most likely occurs through DBF4. Two-hybrid analysis indicates that the Rad53p protein binds to Dbf4p. Furthermore, the steady-state level of DBF4 message and Dbf4p protein is reduced in several rad53 mutant strains, indicating that RAD53 positively regulates DBF4. These results suggest that two different functions of the cell cycle, initiation of DNA replication and the checkpoint function, can be coordinately regulated through the common intermediate RAD53.

Distribution of exchanges upon homologous recombination of exogenous DNA in Xenopus laevis oocytes.

Homologous recombination between DNA molecules injected into Xenopus oocyte nuclei was investigated by examining the recovery of information from differentially marked parental sequences. The injected recombination substrate was a linear DNA with terminal direct repeats of 1246 bp; one repeat differed from the other by eight single base-pair substitutions, distributed throughout the region of homology, each of which created or destroyed a restriction enzyme site. Recombination products were recovered and analyzed for their content of the diagnostic sites, either directly by Southern blot-hybridization or after cloning in bacteria. The majority (76%) of the cloned products appeared to be the result of simple exchanges-i.e., there was one sharp transition from sequences derived from one parent to sequences derived from the other. These simple exchanges were concentrated near the ends of the homologous interval and, thus, near the sites of the original molecular ends. Placing marked sites on only one side of the homologous overlap showed that marker recovery was governed largely by the positions of the molecular ends and not by the markers themselves. When a terminal nonhomology was present at one end of the substrate, the yield of recombinants was sharply decreased, but the pattern of exchanges was not affected, suggesting that products from end-blocked substrates arise by the same recombination pathway. Because of considerable evidence supporting a nonconservative, resection-annealing mechanism for recombination in oocytes, we interpret the distribution of exchanges as resulting from long-patch repair of extensive heteroduplex intermediates.

Activation of the coagulation system in cancerogenesis and metastasation.

The activation of the coagulation system in cancer patients is a well-known phenomenon responsible for recurrent clinical problems. A number of fascinating molecular mechanisms have been recognized showing that the tumor not only activates the coagulation system, but vice versa, activated coagulation proteins are able to induce molecular effects in tumor cells. The molecular basis is the expression of defined membrane receptors by tumor cells that are activated, for example, by thrombin. As the liberation of thrombin from prothrombin is one of the key events in coagulation, it's impact upon biological processes, such as cancerogenesis and metastasation, seems to be a regular pathophysiological consequence. These perceptions are not only interesting for the comprehension of cancerogenesis, metastasation, and clinical phenomena, but they also have a high impact upon modern strategies of tumor therapy. Especially, the development of clinically useful coagulation inhibitors, such as modern low molecular weight heparins or melagatran, created the possibility of therapies that combine cell biological approaches with apoptosis-inducing principals such as chemotherapy. Several clinical studies that demonstrate the implication of these strategies have already been published recently. In this article the cell biological basics for these approaches are reviewed.

Combretastatin A-4 prodrug inhibits growth of human non-small cell lung cancer in a murine xenotransplant model.

BACKGROUND: Combretastatin A-4 prodrug (CA-4PD) has been identified as a potent antivascular agent in various rodent tumor models. The aim of this study was to investigate the effect of CA-4PD on human non-small cell lung cancer (NSCLC). METHODS: Cytostatic and cytotoxic effects of CA-4PD on selected NSCLC cells, Colo-699 and KNS-62, were studied in vitro. After subcutaneous xenotransplantation the effect of systemically administrated CA-4PD on tumor growth was investigated in vivo. A newly established orthotopic xenotransplant model was employed to estimate prolongation of survival after intrapulmonary tumor induction with secondary metastatic disease. RESULTS: In vitro, CA-4PD displayed a time and dose dependent antiproliferative effect on human lung cancer cells. In vivo, CA-4PD significantly delayed growth of subcutaneously induced lung cancer. This growth delay was translated into a prolongation of survival in the metastasizing orthotopic xenotransplant model. CONCLUSIONS: In vitro CA-4PD inhibits proliferation of NSCLC cells, most likely by disruption of microtubule assembly. In vivo, systemic treatment inhibits growth of subcutaneously xenotransplanted tumors by an antivascular effect. In the case of metastasizing human lung cancer this translated into a prolongation of survival.

An improved orthotopic xenotransplant procedure for human lung cancer in SCID bg mice.

BACKGROUND: Overall prognosis in human lung cancer is still poor. A highly reproducible, easy to perform in vivo model, which closely resembles the clinical features of advanced human lung cancer, is required for the evaluation of novel therapies. METHODS: Tumor cells, originated from a human adenocarcinoma, a squamous cell carcinoma, and an undifferentiated large cell carcinoma, were xenotransplanted heterotopically by subcutaneous and intravenous injection and compared with orthotopic intrapleural and intrapulmonary xenotransplantation by a facilitated engraftment procedure into SCID bg mice. RESULTS: Subcutaneous injection of tumor cells resulted in a 100% engraftment rate with establishment of solid tumors without clinically relevant metastases. Intravenous injection had poor engraftment rates by hematogenous spread. Depending on the cell line, a 80% to 100% engraftment rate in orthotopic xenotransplantation was achieved, resulting in a consistent pattern of mediastinal and bilateral pulmonary metastases. CONCLUSIONS: The facilitated orthotopic xenotransplantation of human lung cancer is easy to perform and results in a reproducible in vivo model that closely resembles the clinical features of advanced human lung cancer. Consequently, this model appears suitable for in vivo evaluation of novel cancer therapies in preclinical tests.

Effective treatment of malignant pleural effusion by minimal invasive thoracic surgery: thoracoscopic talc pleurodesis and pleuroperitoneal shunts in 101 patients.

BACKGROUND: For effective palliation of patients with malignant pleural effusion due to advanced neoplastic disease, any proposed treatment should have low procedure-related mortality and morbidity. METHODS: The clinical outcome of 119 thoracoscopies in 101 patients (56 women, 45 men), from 42 to 91 years of age (mean, 68 +/- 9 years) with malignant pleural effusions was evaluated in a retrospective study. Video-assisted thoracoscopy (VATS) talc pleurodesis was done in 105 instances, and a pleuroperitoneal shunt was performed 14 times as an alternative when complete expansion of the lung could not be achieved due to tumor implants on the visceral pleura. RESULTS: The VATS talc pleurodesis resulted in clinically significant improvement of dyspnea in 92.2% of the patients. Thirty-day mortality was 2.8% and morbidity was 2.8%. The mean duration of postoperative survival was 6.7 months. Recurrent pleural effusion occurred in 5.7% of patients after a mean interval of 6 months. Clinical relief of dyspnea was obtained in 73% of the patients treated with pleuroperitoneal shunts. Thirty-day mortality in this group was 21% and morbidity was 14.3%. The mean duration of survival was 4.2 months. CONCLUSIONS: The VATS talc pleurodesis is appropriate for palliation of patients with malignant pleural effusions and should be performed once the diagnosis has been confirmed. Patients with lungs trapped by visceral carcinomatosis may benefit from placement of a pleuroperitoneal shunt as an alternative.

Recurrent subarachnoid hemorrhage complicating a traumatic carotid-cavernous fistula.

Recurrent subarachnoid hemorrhage complicated a traumatic carotid-cavernous fistula in a young man. The fistula drained predominantly into the deep venous system of the brain, where the hemorrhage was thought to have occurred.

Intracranial subdural hematoma after lumbar myelography.

Two cases of intracranial subdural hematoma after lumbar myelography are reported. This complication should be considered in patients who complain of prolonged headache or who develop neurological signs after lumbar puncture.

Evaluation of amniotic membrane as adhesion prophylaxis in a novel surgical gastroschisis model.

Adhesions are a leading cause of bowel obstruction and infertility. The coverage of peritoneal defects, as in gastroschisis, is still a crucial problem. Despite biodegradable substitutes and synthetic implants such as PTFE membrane, a satisfactory replacement for gastroschisis has not been identified. The amniotic membrane, which is available at birth with a low antigenicity, was evaluated as a peritoneal substitute. Viable, partially viable, and inversed-used amniotic membranes were compared in a rat model. A full-thickness abdominal wall defect was made and the amniotic membrane sutured into this defect. The skin was closed over the amniotic membrane. Reoperation was performed 3 weeks after initial surgery, and the adhesion formation was measured by computerized area calculation. Viable amniotic membrane showed 0 to 3% area adhesion formation, while partially viable (50%) amniotic membrane demonstrated 33% area adhesion formation. Inversed-used amniotic membrane, with the stromal side directed toward the abdominal cavity, showed 70% of the amniotic membrane area to be covered with adhesions. The same amount was found in the control group, in which no substitute was sutured into the defect. This animal model is suitable for the straightforward evaluation of peritoneal substitutes with regard to adhesion formation. It is easy to perform and mimics surgical needs. Viable amniotic membrane proved to be an excellent antiadhesive tissue.

Epilepsy and primary cerebral tumours.

Although the association of epilepsy with cerebral tumours is well recognized, the reported incidence of seizures and relationship to tumour pathology varies significantly. This study assessed retrospectively the incidence of seizures, relationship to tumour pathology, natural history of epilepsy and prognostic significance of presentation with a seizure in 120 consecutive adults with histologically proven primary cerebral hemisphere tumours including meningiomas. 52% had a seizure and most were at presentation. Seizures were more common with anaplastic astrocytoma (AA) (18 23 ) than glioblastoma multiforme (21 56 ) (p = 0.001) and seizure occurrence was associated with cortical invasion. 52% of meningioma patients had a seizure. Seizures recurred in 34%, more frequently with glioma (19 of 46) than meningioma (1 of 15) (p < 0.05). Patients with AA presenting with a seizure had a longer survival (28 months) than patients without seizure (8 months) (p = 0.05 one sided). In conclusion, seizures are a common complication of cerebral tumours, usually at presentation and correlate with tumour pathology. A seizure at presentation in AA correlates with longer survival.

[Pain therapy after thoracoscopic interventions. Do regional analgesia techniques (intercostal block or interpleural analgesia) have advantages over intravenous patient-controlled opioid analgesia (PCA)?]. / Schmerztherapie nach thoracoskopischen Eingriffen. Haben Regionalanalgesieverfahren (Intercostalblockade oder Interpleuralanalgesie) Vorteile gegenüber einer intravenösen patientenkontrollierten Opioidanalgesie (PCA)?

Systemic opioids and thoracic epidural analgesia are common techniques used to provide post-operative analgesia following thoracoscopy (video-assisted thoracic surgery). The aim of the present prospective randomised study was to evaluate the efficacy of two less invasive analgesic techniques, intercostal blocks (ICB) and interpleural analgesia (IPA). After approval from the ethics committee and informed consent from the patients, 36 patients scheduled for thoracoscopic surgery were randomly assigned to a group for postoperative pain management: group ICB: intercostal blocks of the segments involved with 5 ml 0.5% bupivacaine at the end of surgery and 6 h later; group IPA: interpleural analgesia with 20 ml 0.25% bupivacaine applied every 4 h using a catheter placed during surgery near the apex of the interpleural space; control group: IV-opiod-PCA with piritamide. Patients in the ICB and IPA groups had access to pain relief by PCA with piritramide as well. Additional medication for all groups if the analgesia was insufficient consisted of metamizol. There were no significant differences in piritramide consumption between the two regional analgesia groups and the control group up to the 3rd and 7th postoperative day. Up to the 7th day piritramide consumption in group ICB was 78 mg, in group IPA 75 mg and 80 mg in the control group. Patients in group ICB showed significantly less pain at rest measured by the visual analogue scale (VAS) on the 1st postoperative day (U-test, P < 0.05), but otherwise there were no statistical differences regarding pain scores. Respiratory parameters such as forced vital capacity, forced expiratory volume, peak flow and the Tiffeneau test (FVC, FEV1, PF, FEV1/FVC) were reduced significantly after thoracoscopy and showed a slow recovery in all three groups without significant intergroup differences. Thoracoscopic surgery causes less and shorter lasting pain in comparison to thoracotomy. Nevertheless, effective pain management is necessary. We could not demonstrate a significant reduction in piritramide consumption for the techniques of regional analgesia tested here (ICB, IPA). We conclude that the use of these techniques is not complementary after thoracoscopy, since an opioid (PCA with piritramide) combined with a non-opioid (metamizol) resulted in satisfactory analgesia.

Apoptosis by gemcitabine in non-small cell lung cancer cell line KNS62 is induced downstream of caspase 8 and is profoundly blocked by Bcl-xL over-expression.

BACKGROUND: This study assesses the chemotherapeutic drug gemcitabine in the human non-small cell lung cancer (NSCLC) cell line KNS62 in relation to the CD95-induced apoptotic pathway, and the role of the anti-apoptotic protein Bcl-xL in vitro and in vivo. MATERIALS AND METHODS: Apoptosis was determined by JAM assay and DAPI staining analysis. Activation of key apoptotic proteins, including caspases 3, 8 and 9 and BID, as well as cytochrome c release and mitochondrial transmembrane potential (MTP), were measured. The impact of the caspase inhibitor zVAD on gemcitabine-induced apoptosis was quantified. The in vitro results were verified in vivo in an orthotopic murine xenotransplantation model. RESULTS: Gemcitabine treatment, as well as stimulation of CD95, resulted in cleavage of effector caspase 3 as well as its substrate PARP and caspase 9, followed by DNA fragmentation. Cleavage of caspase 8 was demonstrated after CD95 activation but not after the application of gemcitabine. In KNS62-Bcl-xL clones, release of cytochrome c and loss of mitochondrial transmembrane potential were suppressed. Consequently, apoptosis after gemcitabine therapy, as well as CD95-induced apoptosis, were significantly inhibited. Caspase inhibitor zVAD only partly reversed gemcitabine-induced DNA fragmentation. In vivo, there was a significant reduction in tumour volume under gemcitabine therapy. Bcl-xL over-expressing tumours were completely resistant to gemcitabine therapy. CONCLUSIONS: In NSCLC cell line KNS62 gemcitabine activated the mitochondrial apoptotic pathway downstream of mitochondria without activation of initiator caspases. Bcl-xL over-expression induced significant resistance to gemcitabine. In vivo, the anti-apoptotic effect of Bcl-xL was more pronounced than in vitro. Gemcitabine also induced caspase-independent DNA fragmentation in KNS62 cells.

[Orthograde intestinal irrigation in infants and small children]. / Zur orthograden Darmspülung bei Säuglingen und Kleinkindern.

Orthograde whole-gut irrigation proved a simply applicable method for bowel cleansing also in infants and small children. It could be demonstrated that the use of saline-lavage solution is well tolerated by these patients, accompanied only by minor changes of electrolyte and pH balance. Orthograde whole-gut irrigation is indicated in operations for small and gross bowel surgery. It is contraindicated, however, in marked bowel stenoses and also, to a lesser degree, in functional bowel stenoses.

[Implementing the employment schedule act at a university clinic--"surgical research during illegal time periods"]. / Realisierung des Arbeitszeitgesetzes an einer Universitätsklinik--"Chirurgische Forschung im illegalen Zeitraum".

The realisation of the new regulations for working time in hospitals by law (ArbZG) creates a new status for clinical research. The ArbZG clearly includes regulations for times spent on research and teaching. The strict regulations for resting periods, which have to be respected, allow research activities almost only in time spans other than official working time. The council of the European Union has excluded research activities from the guidelines for working time regulations, so there are no limitations on the time spent on research. In contrast, the German regulations for working time include time spent on research, so there is a national disadvantage for research in comparison to other European countries.

[Profile and structure of future-oriented visceral surgery in a non-university environment]. / Profil und Struktur einer zukunftsorientierten Visceralchirurgie im nichtuniversitären Bereich.

A nationwide limitation of the total health care budget requires the shutdown of certain departments or complete hospitals in order to increase the budget for the surviving hospitals. This development involves surgical departments as well, which have to be re-designed for an economic future.

Low-cost teleradiology for Australia.

Teleradiology refers to the transmission of clinical images from their source to remote sites. In this paper a low-cost means of establishing teleradiology using conventional personal computers is described. This is a simple and effective means of transmitting valuable clinical data from hospital to hospital, and hospital to individual, markedly enhancing the quality of clinical communication. The system described herein has proved invaluable in a busy neurosurgical department, in both emergency and more routine settings. Teleradiology has the potential to transform the early management of critically ill and injured patients, especially those from remote parts of Australia.