Activation of the cell membrane angiotensin AT2 receptors in human leiomyosarcoma cells induces differentiation and apoptosis by a PPARγ - dependent mechanism.

Angiotensin II (Ang II), the main effector peptide of the renin-angiotensin system (RAS), acting on AT1 and AT2 receptors participates in the regulation of proliferation, differentiation and apoptosis in tumour cells. The peroxisome-proliferator activated receptor γ (PPARγ) and its ligands exert anti-tumour effects in various human cancer cell lines. The present study investigates the effects initiated by AT1- and AT2 receptor stimulation in SK-UT-1 cells, a human leiomyosarcoma cell line, and clarifies the role of the PPARγ in the AT2 receptor-induced differentiation and apoptosis.Selective stimulation of AT1- and AT2 receptors was achieved by incubation of the cells with Ang II (10-6 M) in the presence of the selective AT2 receptor antagonist, PD 123177 (10-6 M) and the AT1 receptor antagonist, losartan (10-5 M), respectively, the selective PPARγ antagonist, GW 9662, was used at concentration 10-6 M. The expression of smooth muscle cell differentiation markers, SM22α and calponin, was analysed at RNA- and protein levels using RT PCR and Western blot, which was also used to quantify Bcl-2-, Bax- and cleaved caspase-3 proteins. The translocation of the AT2-receptor interacting protein 1 (ATIP1) to the nuclei was studied by Western blot and immunofluorescence staining. The mitochondrial status and the metabolic activity in response to AT1- and AT2 receptor activation were assessed by the quantification of 99mTc - sestamibi and 2´-deoxy-2´-[18F]fluoro-D-glucose uptake.AT1 receptor stimulation did not exert any profound effects in quiescent SK-UT-1 cells. The effects induced by Ang II acting on AT2 receptors were time-dependent. A short, 3 - 6 h lasting stimulation promotes differentiation, i.e increases in the mRNA- and protein levels of SM22α and calponin, whereas a sustained stimulation for 48 h activates the intrinsic apoptotic pathway, as evidenced by reduced cell numbers, down-regulation of the anti-apoptotic Bcl-2 protein and increased levels of the Bax protein and cleaved caspase-3. The effects were reversed by the PPARγ antagonist, GW 9662, clearly implying a PPARγ-dependent mechanism. Our results also demonstrate a co-localisation of the AT2-receptor interacting protein, ATIP1, and the PPARγ in nuclei of SK-UT-1 cells and an accumulation of ATIP1 in the nuclear fraction in response to AT2 receptor stimulation. The regulation of the differentiation and apoptosis via the AT2 receptor favours an important functional role of this receptor in quiescent, slow-cycling SK-UT-1 cells and provides the rationale for the use of AT1 receptor antagonists for the treatment of human leiomyosarcomas.

[Recruiting and Personal Development in Surgical Departments of Large Referral Centers - Current Practice and Options for Improvement from Industry and Service Business]. / Personalgewinnung und -entwicklung in viszeralchirurgischen Kliniken von Großkrankenhäusern ­ derzeitiger Stand und Möglichkeiten der Optimierung aus Industrie und Dienstleistungsgewerbe.

Background Cut-throat competition, cost pressure, generation Y, shortage of qualified staff and feminisation influence human resources management in visceral surgery. The assessment of the current situation by chief surgeons (CS) as well as proof of transferability of strategies from industry and service business (ISB) have not yet been investigated. Material and Methods The CS of university hospitals and large referral centres (> 800 beds) were interviewed (n = 100) on the basis of a standardised questionnaire including 43 items. Closed questions were designed with a 5-point Likert scale and their analysis was presented as means (MW) and standard deviations (±). Ten human resources manager (HMR) of ISB were invited to participate in 45-minute telephone interviews. Results Thirty-seven CS participated in the survey, 15 of whom were full professors. Unsolicited applications (100%), job advertisements (78%) and direct approaches to final year students (78%) were the most common ways of recruitment. Only 17% of CS used a standardised form for preparation. Professional expertise (MW 2.2 ± 0.9), social skills (MW 1.9 ± 0.6) and excellent German language skills (MW 1.8 ± 0.8) were named as important qualifications for employment, while references and certificates were regarded as being less important (MW 3.2 ± 0.9). Personal development was regarded as important (MW 1.1 ± 0.2), but a defined period for residency was not guaranteed (MW 3.0 ± 1.5). Transparent selection criteria for career opportunities (MW 2.5 ± 1.1) and different career models (MW 2.7 ± 1.2) were only rarely available. Six HRM participated in the interviews. Active head-hunting (75%), Internet platforms (75%), presentations at conferences (75%), as well as hiring trainees (50%), job advertisements (50%) and social media (50%) were established options to find qualified employees. Professional and management careers were often separate career paths, while social expertise was regarded as being crucial for filling management positions. Conclusion In visceral surgery, unsolicited applications, job advertisements and direct approaches to final year students are the most common ways for recruitment. Diversified professional and management careers are not yet established. Recruiting strategies that are successful in ISB - such as active scouting and use of social media - should be evaluated for visceral surgery, as well as diversified career models.

[Long-term results of sentinel node biopsy diagnostics in penile carcinoma : Dynamic sentinel node biopsy in cases with nonpalpable lymph nodes in the groin]. / Langzeitergebnisse der Sentinel-Lymphknotendiagnostik beim Peniskarzinom : Dynamische Sentinel-Lymphknotenbiopsie bei nicht-palpablen Leistenlymphknoten.

OBJECTIVE: Dynamic sentinel node biopsy (DSNB) has been recommended in the EAU guidelines for several years as a minimally invasive method for lymph node staging in patients with penile carcinoma and nonpalpable lymph nodes. However, due to the high methodological demands and the primarily unreliable results, this method is rarely used in Germany. The aim of this study was to establish the reliability and morbidity of this method. MATERIAL AND METHODS: The frequency of lymph node recurrent disease and complications were prospectively recorded in patients with initially nonpalpable inguinal lymph nodes and histologically negative sentinel lymph nodes. Quality criteria were the false negative rate (percentage of lymph node recurrence in negative procedures) and the morbidity rate. Inguinal regions with palpable lymph nodes and/or evidence of metastases were not considered. RESULTS: The study included 37 patients with histologically negative sentinel lymph nodes in 63 groins with nonpalpable inguinal lymph nodes. There were 21 T1(a/b) stages, 10 T2, and 6 T3 stages. Tumor differentiation was good in 4, moderate in 26, and poor in 7 patients. During a median follow-up of 52 months (range 1-131 months), we observed a bilateral lymph node recurrence in 1 patient and a conservatively managed prolonged lymphorrhea in another patient. Per inguinal region the false-negative rate was 3.2 % and the morbidity rate was 1.6 %; seen per patient the rates were both 2.7 %. CONCLUSIONS: DSNB is a reliable method of lymph node staging in patients with penile carcinoma and nonpalpable inguinal lymph nodes. The high degree of reliability in combination with the low morbidity justifies the higher methodical complexity of this method.

[Sentinel lymph node biopsy for penile carcinoma : Assessment of reliability]. / Sentinel-Lymphknotenbiopsie beim Peniskarzinom : Überprüfung der Zuverlässigkeit.

BACKGROUND: The European Association of Urologists recommends dynamic sentinel node biopsy (DSNB) as the first choice diagnostic approach for lymph node staging of non-palpable inguinal lymph nodes in penile carcinoma. The aim of this study was to assess the reliability of minimally invasive inguinal DSNB. MATERIAL AND METHODS: Between 2004 and 2012 DSNB was used in all patients with invasive penile carcinoma and non-palpable inguinal lymph nodes. For assessment of reliability the rate of false negative results was determined and complications were documented. The results were analyzed prospectively. RESULTS: In the study period DSNB was performed in a total of 29 patients and it was possible to prove lymph node metastasis in 2 patients with 1 patient who developed lymph node metastasis after a negative DSNB. Thus the false negative rate was 3.70 %. A morbidity rate of 3.45 % was also observed. CONCLUSION: Sentinel lymph node biopsy is a reliable diagnostic method. The sophisticated requirements both methodologically and logistically suggest that this procedure should only be performed in specialized centres.

Activation of cerebral peroxisome proliferator-activated receptors γ (PPARγ) reduces neuronal damage in the substantia nigra after transient focal cerebral ischaemia in the rat.

AIM: The function of brain (neuronal) peroxisome proliferator-activated receptor(s) γ (PPARγ) in the delayed degeneration and loss of neurones in the substantia nigra (SN) was studied in rats after transient occlusion of the middle cerebral artery (MCAO). METHODS: The PPARγ agonist, pioglitazone, or vehicle was infused intracerebroventricularly over a 5-day period before, during and 5 days after MCAO (90 min). The neuronal degeneration in the SN pars reticularis (SNr) and pars compacta (SNc), the analysis of the number of tyrosine hydroxylase-immunoreactive (TH-IR) neurones and the expression of the PPARγ in these neurones were studied by immunohistochemistry and immunofluorescence staining. The effects of PPARγ activation on excitotoxic and oxidative neuronal damage induced by glutamate and 6-hydroxydopamine were investigated in primary cortical neurones expressing PPARγ. RESULTS: Pioglitazone reduced the total and striatal infarct size, neuronal degeneration in both parts of the ipsilateral SN, the loss of TH-IR neurones in the SNc and increased the number of PPARγ-positive TH-IR neurones. Pioglitazone protected primary cortical neurones against oxidative and excitotoxic damage, prevented the loss of neurites and supported the formation of synaptic networks in neurones exposed to glutamate or 6-hydroxydopamine by a PPARγ-dependent mechanism. CONCLUSIONS: Activation of cerebral PPARγ confers neuroprotection after ischaemic stroke by preventing both, neuronal damage within the peri-infarct zone and delayed degeneration of neurones and neuronal death in areas remote from the site of ischaemic injury. Pioglitazone and other PPARγ agonists may be useful therapeutic agents to prevent progression of brain damage after cerebral ischaemia.

New approach for the synthesis of [18F]fluoroethyltyrosine for cancer imaging: simple, fast, and high yielding automated synthesis.

O-(2-[(18)F]fluoroethyl)-L-tyrosine ([(18)F]FET) is one of the first (18)F-labeled amino acids for imaging amino acid metabolism in tumors. This tracer overcomes the disadvantages of [(18)F]fluorodeoxyglucose, [(18)F]FDG, and [(11)C]methionine, [(11)C]MET. Nevertheless, the various synthetic methods providing (18)F[FET] exhibit a big disadvantage concerning the necessity of two purification steps during the synthesis including HPLC purification, which causes difficulties in the automation, moderate yields, and long synthesis times >60 min. A new approach for the synthesis of [(18)F]FET is developed starting from 2-bromoethyl triflate as precursor. After optimization of the synthesis parameters including the distillation step of [(18)F]-FCH(2)CH(2)Br combined with the final purification of [(18)F]FET using a simple solid phase extraction instead of an HPLC run the synthesis [(18)F]FET could be significantly simplified, shortened, and improved. The radiochemical yield (RCY) was about 45% (not decay corrected and calculated relative to [(18)F]F(-) activity that was delivered from the cyclotron). Synthesis time was only 35 min from the end of bombardment (EOB) and the radiochemical purity was >99% at the end of synthesis (EOS). Thus, this simplified synthesis for [(18)F]FET offers a very good option for routine clinical use.

Simplified fast and high yielding automated synthesis of [18F]fluoroethylcholine for prostate cancer imaging.

(11)C- and (18)F-labeled choline analogues are successful tracers for prostate cancer imaging using positron emission tomography (PET). Due to the practical advantages of the longer-living radioisotope (18)F (t(1/2)=110 min) instead of (11)C (t(1/2)=20 min), [(18)F]fluoroethylcholine has been introduced to increase the opportunity of widespread clinical application. Nevertheless, the various known synthetic methods provide [(18)F]fluoroethylcholine for human use only in moderate overall yields of up to 30% so far. Here, a new simplified and high yield two-step-synthesis for [(18)F]fluoroethylcholine is described for potential clinical applications starting from 2-bromoethyl triflate (BETfO) using a modified, commercially available fully automated synthesis module. All synthesis parameters were subsequently optimized resulting in a total yield of 47+/-5% (not decay corrected) in only 40min. [(18)F]fluoroethylcholine could be obtained ready for human use as physiological solution after fixation on Sep-Pak Accell Light cartridges (waters((R))) and formulation with saline without the need of GC or HPLC purification. Radiochemical purity was >99.9% and no contamination of the sterile solution with chemicals used during the synthesis was detected.

[Extended sentinel lymph node dissection in radical prostatectomy for prostate cancer: a study in the Kiel risk population]. / Die extendierte Sentinel-Lymphadenektomie im Rahmen der radikalen Prostatektomie? : Untersuchungen im Kieler Risikokollektiv.

Extended lymph node dissection during radical prostatectomy for prostate cancer remains a disputed area. Sentinel lymph scans help identify the first lymph node stages in the lymph drainage of the prostate. This study was designed to investigate the detection rate of lymph node metastasis by extended lymph node dissection and sentinel lymph node scanning in patients undergoing radical retropubic prostatectomy (RRP) for localized prostate cancer. In this study at our department from 2005 to 2006, a total of 108 patients with localized prostate carcinoma were treated with radical prostatectomy including extended lymph node dissection. A sentinel lymph node scan with 160 MBq of technetium-99m-Nanocoll (Tc) was performed 1 day before surgery. A C-Trak gamma probe (AEA Technologies, Morgan Hills, CA, USA) was used intraoperatively to detect the sentinel lymph nodes. Scan findings were correlated with tumor stage, Gleason score, prostate-specific antigen (PSA) level, and histological lymph node status. Scans revealed sentinel lymph nodes on the film 2 h after Tc administration in 98 of 108 patients (91%). Histologically proven lymph node metastases were detected in 15 of those 98 patients (15%) with a positive sentinel scan. Those 15 patients had a PSA level greater than 10 ng/ml or a Gleason score greater than 6 and at least a pT2 tumor. Specifically, six patients had a pT2 tumor, and nine patients had a pT3 tumor. Of patients placed in a risk group defined as PSA above 10 ng/ml or Gleason score greater than 6, 15 out of 50 patients (30%) had sentinel positive lymph nodes with metastasis. These data suggest that extended sentinel lymph node dissection helps identify lymph node metastasis in patients with PSA above 10 ng/ml or a Gleason score above 6 in 30% of cases. Further studies will show whether these numbers will hold true in patients undergoing radical prostatectomy for prostate cancer.

[Protective effect of pyridoxilate on the hypoxic myocardium. Experimental studies]. / Effet protecteur du piridoxilate sur le myocarde hypoxique. Etudes expérimentales.

The protective action of piridoxilate on hypoxic myocardium has been studied on rats in acute hypoxia (isolated heart, perfused with a non-oxygenated solution) and in prolonged hypoxia (3 days at high [3454 m] altitude). Piridoxilate maintained a higher ATP level with a much lower production of lactate. The mechanisms of action of piridoxilate are probably fairly similar to those of Na dichloracetate.