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AIM: Our aims were to assess the phylogeographic patterns of genetic diversity in eastern Mediterranean water frogs and to estimate divergence times using different geological scenarios. We related divergence times to past geological events and discuss the relevance of our data for the systematics of eastern Mediterranean water frogs. LOCATION: The eastern Mediterranean region. METHODS: Genetic diversity and divergence were calculated using sequences of two protein-coding mitochondrial (mt) genes: ND2 (1038 bp, 119 sequences) and ND3 (340 bp, 612 sequences). Divergence times were estimated in a Bayesian framework under four geological scenarios representing alternative possible geological histories for the eastern Mediterranean. We then compared the different scenarios using Bayes factors and additional geological data. RESULTS: Extensive genetic diversity in mtDNA divides eastern Mediterranean water frogs into six main haplogroups (MHG). Three MHGs were identified on the Anatolian mainland; the most widespread MHG with the highest diversity is distributed from western Anatolia to the northern shore of the Caspian Sea, including the type locality of Pelophylax ridibundus. The other two Anatolian MHGs are restricted to south-eastern Turkey, occupying localities west and east of the Amanos mountain range. One of the remaining three MHGs is restricted to Cyprus; a second to the Levant; the third was found in the distribution area of European lake frogs (P. ridibundus group), including the Balkans. MAIN CONCLUSIONS: Based on geological evidence and estimates of genetic divergence we hypothesize that the water frogs of Cyprus have been isolated from the Anatolian mainland populations since the end of the Messinian salinity crisis (MSC), i.e. since c. 5.5-5.3 Ma, while our divergence time estimates indicate that the isolation of Crete from the mainland populations (Peloponnese, Anatolia) most likely pre-dates the MSC. The observed rates of divergence imply a time window of c. 1.6-1.1 million years for diversification of the largest Anatolian MHG; divergence between the two other Anatolian MHGs may have begun about 3.0 Ma, apparently as a result of uplift of the Amanos Mountains. Our mtDNA data suggest that the Anatolian water frogs and frogs from Cyprus represent several undescribed species.

A family of interspersed repetitive elements, RlBamHI, with sequence similarity to the transposase of hAT DNA transposons, occurs in genomes of eight western Palaearctic water frog taxa and the brown frog Rana dalmatina, but was not detected in Xenopus laevis or Salamandra salamandra. RlBamHI elements are not tandemly arrayed, are dispersed across all chromosomes although not uniformly distributed, and based on dot-blot hybridizations may constitute as much as approximately 10% of the genomes of Rana lessonae, Rana ridibunda, and Rana perezi, but only approximately 1% of that of Rana saharica. Eleven nucleotide sequences of a 572 bp fragment from the nine taxa are very similar (pairwise differences 0.4–8.1% for nucleotides, 0.6–18.2% for amino acids), and all share a single open reading frame across the whole RlBamHI fragment. The reading frame is maintained despite several indels, most of which are multiples of 3 bp, but a pair of which in one species alters and, after 13 codons, restores the reading frame. It is possible that the reading frame is selectively maintained, suggesting recent or even present transposition capacity. The amino acid sequences encoded by RlBamHI elements, but not the nucleotide sequences themselves, reveal the similarity of RlBamHI to members of the widespread hAT superfamily of DNA transposons. Amino acid sequence comparisons permitted no convincing phylogenetic placement of RlBamHI among 32 representative hAT transposons across organisms, probably reflecting both the genetic divergence of RlBamHI elements and the paucity of aligned residues available for analysis. Among DNA transposons, a genomic fraction of 10% is extraordinarily high. Phylogenetic analyses of Rana RlBamHI sequences match poorly with independent genetic and molecular phylogenies; the elements compared probably are not orthologous, which renders their sequences inadequate for reconstructing organismal phylogenetic histories.

Objectives: The C-Pulse® heart assist system (Sunshine Heart, Inc.) is an extra-aortic balloon counterpulsation for the treatment of patients with moderate to severe heart failure of class III or ambulatory class IV according to the NYHA classification refractory to optimal medical therapy. While a first feasibility study in the United States and Canada already showed promising preliminary results, we want to report our experience with the first implantations in Europe. Methods: Between May and July 2013 we implanted the C-Pulse® heart assist system in three male patients 54 years, 54 years and 63 years of age. All patients were on optimal medical therapy and cardiac resynchronization therapy. They were all classified as heart failure stage C as defined by the ACC/AHA classification with two patients in NYHA class III and INTERMACS level 5 and one patient in ambulatory NYHA class IV and INTERMACS level 4. Results: Surgical implantation without cardiopulmonary bypass was successful in all patients. So far no stroke, myocardial infarction, major bleeding or major infection due to the device occurred. One patient developed tachycardia with worsening heart failure 12 hours after surgery without stabilization under medication. The tachycardia prevented the C-Pulse® heart assist system from supporting the heart properly. After further deterioration due to sepsis caused by pneumonia we had to implant a left ventricular assist device 5 days after index procedure. The other two patients clinically improved under the C-Pulse® system. In one patient the RVEF increased from 35% to 50% within 10 days, the LVEF from 25% to 40% within 3 months after implantation. The third patient also showed slight increase of the RVEF after 12 days from 35% to 40% and the LVEF increased from 20% to 35% within 7 weeks. One patient improved from NYHA class III to class II within 6 weeks of observation. Conclusion: The C-Pulse® heart assist system seems to be a promising therapeutic option for patients with moderate to severe heart failure.

Epithelial-mesenchymal transition (EMT) endows cells with migratory and invasive properties, a prerequisite for the establishment of endometriotic lesions. However, the role EMT might play in the pathophysiology of endometriosis is still unknown. Therefore, we examined five recognized markers for EMT in endometrium and endometriosis: E-cadherin, N-cadherin, Twist, Snail and Slug.Immunohistochemistry was used for peritoneal, ovarian and rectovaginal endometriotic lesions (n = 27) and endometrium (n = 13). Reverse transcription polymerase chain reaction was applied to tissue samples and primary cell cultures of endometriotic lesions (n = 9) and endometrium (n = 8).In endometriosis and endometrium E-cadherin, N-cadherin, Twist, Snail and Slug were expressed on protein and mRNA level. E-cadherin expression was strong in epithelial cells, but single E-cadherin-negative cells were frequently present in endometriosis. In endometriosis N-cadherin, Twist and Snail expression were upregulated in comparison with endometrium. The expression of E- and N-cadherin was inversely correlated, while that of N-cadherin and Twist was positively correlated.This study strongly suggests that EMT may be regulated differently in endometriosis and the endometrium. Future research should further elucidate the regulation of EMT in the endometrium and endometriosis.

Water frogs [genus Pelophylax (Rana)] that occur around the eastern Mediterranean Sea provide an opportunity to study early stages of speciation. The geography of the eastern Mediterranean region has changed dramatically since the Middle Miocene as a result of motions of adjoining lithospheric plates and regional-scale vertical crustal motions (uplift and subsidence). For several hundred thousand years between 6 and 5 million years ago (Mya), the Mediterranean basin was isolated from the Atlantic Ocean, and became desiccated (the Messinian Salinity Crisis; MSC). Geological data suggest that the endemic water frog lineage on Cyprus was isolated by the flooding of the Mediterranean basin by salt water at the end of the MSC, circa 5.5–5.3 Mya. This suggests a rate of uncorrected genetic divergence of approximately 1.1% per million years (My). Divergence time estimates based on this rate are in good agreement with the chronology of events in the history of crustal deformation and landscape development in the eastern Mediterranean region.

A 5′ truncated non-LTR CR1-like retrotransposon, named RanaCR1, was identified in the serum albumin intron-1 (SAI-1) of at least seven species of western Palearctic water frogs (WPWF). Based on sequence similarity of the carboxy-terminal region (CTR) of ORF2 and/or the highly conserved 3′ untranslated region (3′ UTR), RanaCR1-like elements occur also in the genome of Xenopus tropicalis and Rana temporaria. Unlike other CR1 elements, RanaCR1 contains a CA microsatellite in its 3′ UTR. The low nucleotide diversity of the 3′ UTR compared to the CTR and to SAI-1 suggests that this region still plays a role in WPWF, either as a structure-stabilizing element, or within a species-specific transcriptional network. Length variation of water frog SAI-1 sequences is caused by deletions that extend in some cases beyond the 5′ or 3′ ends of RanaCR1, probably a result of selection for structural and functional stability of the primary transcript. The impact of RanaCR1 on SAI-1 evolution is also indicated by the significant negative correlation between the length of both SAI-1 and RanaCR1 and the percentage GC content of RanaCR1. Both SAI-1 and RanaCR1 sequences support the sister group relationship of R. perezi and R. saharica, which are placed in the phylogenetic tree at a basal position, the sister clade to other water frog taxa. It also supports the monophyly of the R. lessonae group; of Anatolian water frogs (R. cf. bedriagae), which are not conspecific with R. bedriagae, and of the European ridibunda group. Within the ridibunda clade, Greek frogs are clearly separated, supporting the hypothesis that Balkan water frogs represent a distinct species. Frogs from Atyrau (Kazakhstan), the type locality of R. ridibunda, were heterozygous for a ridibunda and a cf. bedriagae specific allele.

In Western Europe, many pond owners introduce amphibians for ornamental purposes. Although indigenous amphibians are legally protected in most European countries, retailers are circumventing national and international legislation by selling exotic nonprotected sibling species. We investigated to what extent non-native species of the European water frog complex (genus Pelophylax) have become established in Belgium, using morphological, mitochondrial and nuclear genetic markers. A survey of 87 sampling sites showed the presence of non-native water frogs at 47 locations, mostly Marsh frogs (Pelophylax ridibundus). Surprisingly, at least 19% of all these locations also harboured individuals with mitochondrial haplotypes characteristic of Anatolian water frogs (Pelophylax cf. bedriagae). Nuclear genotyping indicated widespread hybridization and introgression between P. ridibundus and P. cf. bedriagae. In addition, water frogs of Turkish origin obtained through a licensed retailer, also contained P. ridibundus and P. cf. bedriagae, with identical haplotypes to the wild Belgian populations. Although P. ridibundus might have invaded Belgium by natural range expansion from neighbouring countries, our results suggest that its invasion was at least partly enhanced by commercial trade, with origins as far as the Middle East. Also the invasion and rapid spread of Anatolian lineages, masked by their high morphological similarity to P. ridibundus, is likely the result of unregulated commercial trade. We expect that Anatolian frogs will further invade the exotic as well as the native range of P. ridibundus and other Pelophylax species elsewhere in Western and Central Europe, with risks of large-scale hybridization and introgression.

European water frog hybrids Rana esculenta (R. ridibunda×R. lessonae) reproduce hemiclonally, by hybridogenesis: in the germ line they exclude the genome of one parental species and produce haploid gametes with an unrecombined genome of the other parental species. In the widespread L-E population system, both sexes of hybrids (E) coexist with R. lessonae (L). They exclude the lessonae genome and produce ridibunda gametes. In the R-E system, hybrid males coexist with R. ridibunda (R); they exclude either their ridibunda or their lessonae genome and produce sperm with a lessonae or with a ridibunda genome or a mixture of both kinds of sperm. We examined 13 male offspring, 12 of which were from crosses between L-E system and R-E system frogs. All were somatically hybrid. With one exception, they excluded the lessonae genome in the germ line and subsequently endoreduplicated the ridibunda genome. Spermatogonial metaphases contained a haploid or a diploid number of ridibunda chromosomes, identified through in situ hybridization to a satellite DNA marker, and by spermatocyte I metaphases containing a haploid number of ridibunda bivalents. The exception, an F1 hybrid between L-E system R. lessonae and R-E system R. ridibunda, was not hybridogenetic, showed no genome exclusion, and evidenced a disturbed gametogenesis resulting from the combination of two heterospecific genomes. None of the hybridogenetic hybrids showed any cell lines excluding the ridibunda genome, the pattern most frequent in hybrids of the R-E system, unique to that system, and essential for its persistence. A particular combination of R-E system lessonae and R-E system ridibunda genomes seems necessary to induce the R-E system type of hemiclonal gametogenesis.

The C-Pulse® system is a non-blood contacting, non-obligatory assist device implanted externally on the ascending aorta and is based on the principle of counterpulsation. Algorithms based on R-wave detection increase coronary blood ow during diastole and reduce arterial impedance during systole with potential bene ts on diastolic function and improved coupling of the ventricle and arterial system. Optimization of C-Pulse timing can be performed during acute ON/OFF interventions. Purpose

The Ensembl (http://www.ensembl.org/) project provides a comprehensive and integrated source of annotation of large genome sequences. Over the last year the number of genomes available from the Ensembl site has increased by 7 to 16, with the addition of the six vertebrate genomes of chimpanzee, dog, cow, chicken, tetraodon and frog and the insect genome of honeybee. The majority have been annotated automatically using the Ensembl gene build system, showing its flexibility to reliably annotate a wide variety of genomes. With the increased number of vertebrate genomes, the comparative analysis provided to users has been greatly improved, with new website interfaces allowing annotation of different genomes to be directly compared. The Ensembl software system is being increasingly widely reused in different projects showing the benefits of a completely open approach to software development and distribution.

To evaluate the efficacy of passive cardiomyoplasty with the determination of biventricular volumes, global systolic function as well as left-ventricular muscle mass.In 19 patients with congestive heart failure of idiopathic or ischemic origin, a polyester mesh-graft was implanted around both ventricles for stabilization and functional support. Before and three months after surgery, 15 patients underwent EBCT and 4 patients with impaired renal function underwent MRI, for the evaluation of the volume and ejection fraction of both ventricles.EBCT demonstrated a decrease from 385 to 310 ml in LV-EDV, from 312 to 242 ml in LV-ESV, from 209 to 160 ml in RV-EDV and from 149 to 87 ml in RV-ESV, and an increase from 20 to 26% in LV-EF and from 37 to 50% in RV-EF as well as a reduction of LV-MM from 300 to 274 g (p0.05 each). Similar results were obtained by MRI.Following passive cardiomyoplasty, EBCT and MRI revealed an improvement of the global systolic function as well as a reduction of biventricular volumes and left-ventricular muscle mass.

Standard for treatment of pHPT has been the exploration of the neck and extirpation of the macroscopic identified adenoma for a long time. Since the Quick-PTH-Assay is available as intraoperative control of success, it is possible to extirpate a preoperativeley localized adenoma without identifying the normal parathyroid glands. Since the accuracy of the preoperative localization is essential for a minimally invasive or endoscopic procedure, we analyzed retrospectively the accuracy of ultrasound and mibiscan of our patients, operated due to pHPT in our facility.Between 1995 and 2002 119 patients were operated due to HPT in our facility. Sensitivity, specificity, positive- and negative-predictive value for diagnosis and correct localisation of a singular adenoma by ultrasound and/or mibiscan were determined.We found a singular adenoma in 94 patients, a carcinoma in 1 patient, 6-times a double-adenoma and in 18 cases a hyperplasia of all parathyroid glands. Sensitivity, specificity, positive- and negative-predictive value for diagnosis and correct localisation of a singular adenoma were 52 %, 41 %, 60 % and 27 % rsp., when the results of mibiscan and ultrasound were used.Related to the preoperative imaging, a single gland exploration and extirpation would have been possible in 70 % of our patients with pHPT. However, in 40 % of these patients the 100 % reliable Quick-PTH-Assay would have shown, that the adenoma has not been removed successfully in the first attempt.

This study characterizes microcirculatory changes (capillary blood flow, capillary permeability, and leukocyte rolling) in the pancreas, colon, liver, and lungs at different stages of severe acute pancreatitis (AP) in a well-established rat model using intravital microscopy and computerized image analysis. The results demonstrate that microcirculatory disorders in severe AP are not confined to the pancreas but can also be found in the colon, liver, and lungs; that they extend beyond the early stage of AP and persist for 48 hr (and longer); and that they not only affect capillary blood flow but also involve prolonged changes of capillary permeability and leukocyte endothelial interaction. These findings may explain previous observations that therapeutic strategies aimed at enhancing microcirculation improve outcome in AP even if therapy is delayed and pancreatic necrosis can no longer be influenced. Since these systemic microcirculatory disturbances may contribute to AP-associated multiple organ dysfunction syndrome, further studies are warranted to evaluate whether improvement of microcirculation stabilizes organ function in AP and how long this may be effective after disease onset.

The objective was to overcome allograft shortage during the Ross operation; stentless xenografts were carefully evaluated for hemodynamic behavior and valve deterioration during medium term follow-up. Between January 10, 1994 and January 4, 1996 nine adult patients (age 31-51 years) underwent aortic valve replacement with an autologous pulmonary valve and right ventricular outflow tract reconstruction with the Edwards Prima or Medtronic Freestyle xenograft. One patient was dead early and one late, both from noncardiac reasons. Forty-eight to 66 months follow-up was available for 7 patients and was performed with physical examination in the outpatient clinic, transthoracic echocardiography (TTE), and magnetic resonance imaging (MRI). Two patients received 29-mm valves and the remaining 27-mm valves. No reoperation became necessary during follow-up. Preoperative left ventricular ejection fraction ranged from 20% to 84%, median 61%, mean 59% +/- 18%. At latest follow-up left ventricular ejection fraction was 49% to 70%, median 57%, mean 58% +/- 8%. TTE showed no calcification of the xenograft wall or cusps. MRI revealed good autograft function with no evidence of stenosis in any patient. Four patients showed no and three trivial regurgitation. Right ventricular outflow tract-stenosis could not be seen in any patient. Calculated gradients of the xenograft valves ranged from 2 to 6 mm Hg, median 3 mm Hg (mean 3.1 +/- 2.4 mm Hg) and calculated EOA ranged from 2.0 to 4.0 cm(2), median 2.8 cm(2). MRI supported these findings and showed pliable xenograft cusps in all patients. Right ventricular function was well preserved in all patients. In adult patients right ventricular outflow tract reconstruction with stentless xenografts can be performed safely and intermediate-term results are encouraging. During medium-term (5-7 years) follow-up no calcification or deterioration of valve function occurred with excellent hemodynamic behavior.

Die chirurgische Behandlung der terminalen Herzinsuffizienz gewinnt zunehmend an Bedeutung. Als Ursachen hierfur sind zum einen quantitative demographische Veranderungen der Patientengruppe und zum anderen die keineswegs lediglich durch das Spenderaufkommen bedingte Stagnation im Bereich der Herztransplantation zu nennen. Die Herztransplantation einer kleinen, hoch selektierten Patientengruppe zeigt gute mittelfristige Ergebnisse mit einer heute allgemein erreichten 1-Jahressterblichkeit von 15-20% und einer etwa 50-60%igen Chance, 5-7 postoperative Jahre zu erleben [7]. Lebenslange Immunsuppression als Gratwanderung zwischen Infektion und Rejektion sowie die im Langzeitverlauf zunehmende Transplantatarteriosklerose bestimmen jedoch erheblich die postoperative Lebensqualitat und -erwartung.

To evaluate the role of cine magnetic resonance imaging (MRI) in the preoperative assessment and postoperative follow-up of patients undergoing left ventricular (LV) reduction surgery.6 patients with cardiomegaly were examined on a 1.5 T MR imager before and after LV reduction surgery. The heart was imaged along the short and long axes using a breath-hold ECG-triggered cine gradient-echo sequence for assessing ventricular and valvular morphology and function and performing volumetry (end-diastolic and end-systolic volumes, ejection fraction).Postoperatively, the mean ejection fraction increased from 21.7% to 33.4% and the end-diastolic and end-systolic left ventricular volumes decreased in all patients (304.0 and 252.5 ml before to 205.0 and 141.9 ml after surgery). Mean myocardial mass decreased slightly from 283.8 g to 242.7 g. Differences were significant for all parameters (p0.05). MRI allowed for the reliable assessment of post-operative valve morphology and yielded additional findings such as the presence of mitral valve insufficiency or ventricular thrombus.Cine MRI provides relevant information prior to left ventricular reduction surgery and reliably depicts functional and morphological changes in the early post-operative follow-up.

The cardiac support device (CSD, Acorn Cardiovasc. Inc.), a knitted polyester tissue, is surgically placed over the ventricles to prevent further dilatation of the heart. The aim of this study was to evaluate the feasibility and safety of CSD implantation in patients with advanced heart failure from cardiomyopathy of either idiopathic or ischemic origin. From April 1999, 23 patients received the CSD. In 8 patients the CSD implantation was the only surgical measure; in 12 patients a concomitant mitral valve repair was performed. In three more patients, the CSD implantation was combined with other surgical procedures. The CSD was placed while on bypass with the heart beating, attached to the AV groove and tailored anteriorly to snugly fit the ventricles. There were no intraoperative deaths or complications. Two patients died early postoperatively (4 d, 21 d); 1 late death occurred (44 d postop). The deaths were not considered to be device related. There were no CSD-related adverse events. Six months postoperatively all patients improved by at least one NYHA class. Echocardiography at 6 months revealed an increase in LVEF; the LVEDD decreased accordingly. Mitral valve regurgitation improved in all patients. These findings indicate that the CSD is safe, and improves heart failure symptoms and left ventricular function. Additional studies have to confirm these results.

Immunosuppressive drugs have been associated with the development and progression of acute pancreatitis after organ transplantation. Consequently, a reduction or a change in immunosuppressive therapy has been recommended once posttransplantation pancreatitis has been suspected. However, it is not known which of the available immunosuppressive agents is most harmful to the pancreas and which may be used safely in this situation. The objective of this study was to investigate the effect of different immunosuppressive drugs in various dosages on intrapancreatic protease activation, acinar cell necrosis, and mortality in an improved model of acute necrotizing pancreatitis in the rat. The rat model of acute necrotizing pancreatitis, like posttransplantation pancreatitis, is characterized by ischemia and microcirculatory disorders.Acute pancreatitis was induced in rats by using a combination of low-dose controlled intraductal glycodeoxycholic acid superimposed on intravenous cerulein hyperstimulation. Six hours thereafter, animals were randomized to intravenous therapy with 2, 10, or 50 mg/kg/day prednisolone (PRED); 3, 15, or 60 mg/kg/day cyclosporine A (CsA); 10 mg/kg/day azathioprine (AZA); 0.6 mg/kg/day orthoclone OKT3 (OKT3); or saline. After 36 hr, surviving animals were killed to determine acinar cell necrosis and trypsinogen activation peptides levels (TAP) in blood and ascites.Compared with saline-treated control rats, animals treated with 60 mg/kg/day CsA developed significantly more acinar cell necrosis and had increased amounts of TAP in ascites. Likewise, there was more extensive acinar cell necrosis in animals subjected to AZA therapy. However, this was not associated with incremental TAP. Animals treated with 3 or 15 mg/kg/day CsA, OKT3, or PRED showed no significant changes in these target parameters. Animals given 10 or 50 mg/kg/day PRED even had decreased hematocrit values and produced significantly less ascites than animals in the other groups.The present results suggest that AZA and high doses of CsA aggravate acute pancreatitis and should, therefore, be avoided once posttransplantation pancreatitis has been suspected, whereas lower doses of CsA, OKT3, and PRED may be used safely. PRED can even be used at higher doses as may be required when graft rejection is suspected.

Traditionally a homograft valve is used as a pulmonary replacement device for the Ross operation. Right ventricular outflow tract reconstruction during aortic valve replacement with an autograft was performed with stentless xenograft valves in nine patients. Hemodynamic performance is satisfying, but, long term evaluation is needed.

Despite the fact that all the progress in technology, surgical technique and pathophysiological knowledge has made aortocoronary bypass surgery a safe routine procedure, there are certain clinical settings where an alternative approach seems to be advantageous. In 50 patients with age ranging from 51 to 74 years with advanced coronary heart disease and poor left ventricular (LV) function, as well as in patients with good LV function and single or double vessel disease not amenable for PTCA and in patients with acute ischemia or recent myocardial infarction, we performed coronary artery bypass grafting (CABG) without cardioplegic arrest during a short period of left ventricular unloading by means of a left ventricular assist device (LVAD). During LVAD support we administered Esmolol to decrease the heart rate and to keep the heart flaccid to facilitate easier peripheral anastomosis on a breathing heart. Preoperative ejection fraction ranged from 15 to 56%. In two patients of the acute MI-group, we continued the left ventricular mechanical support postoperatively, one of them survived. We performed on average 1,4 distal anastomoses and used in 34 cases the left internal mammary artery. All but three patients survived the procedure in stable conditions and could leave intensive care after a mean stay of 1.5 days. There were no perioperative myocardial infarctions. In our view, CABG during LVAD support without heart lung machine and cardioplegia is a safe and life saving procedure. No ischemic damage is applied to the heart and it can be recommended for cautions use in select patients.

Fruhere Studien haben gezeigt, das verschiedene Dextrane die azinare Nekroserate und Mortalitat bei nekrotisierender Pankreatitis signifikant reduzieren. Die vorliegende Studie analysiert die Wirkung von Dextranen auf die Pankreasmikrozirkulation bei nekrotisierender Pankreatitis der Ratte.

Slices of the rabbit caudate nucleus, preincubated with [3H]dopamine and subjected to electrical field stimulation, were used (1) to investigate the involvement of G-proteins in the signal transduction of presynaptic D2 (auto)receptors and κ-opioid receptors on dopaminergic axon terminals in this tissue and (2) to study a possible mutual interaction of these two presynaptic receptors. Pretreatment of the slices with either pertussis toxin (8 μg/ml; 18 h), or N-ethylmaleimide (30 μM, 30 min) significantly reduced the inhibitory effects of both the D2 agonist quinpirole and the κ-opioid receptor agonist U-50488H on the [3H]overflow evoked by 36 pulses (2 ms, 24 mA, 0.3 Hz), suggesting the coupling of both receptors to G-proteins. Experiments designed to study possible interactions of these two presynaptic receptors were carried out under stimulation conditions (only 1 pulse), which strongly diminish interference of endogenous transmitters released in the tissue with modulatory effects of exogenous drugs. For instance, due to the presence of endogenous dopamine, quinpirole was much less potent during 36-pulse-than during 1-pulse field stimulation, whereas the D2 antagonist domperidone was almost without effect in the latter case. Using the 1-pulse stimulation paradigm, the concentration/response curve of quinpirole was unaffected in the presence of the halfmaximal inhibitory concentration of U-50,488 H (0.1 μM). On the other hand, also quinpirole at its halfmaximal inhibitory concentration (0.1 μM), hardly affected the concentration/response curve of U-50,488 H: only high concentrations of U-50,488 H (above 1 μM) seemed to be slightly less effective in the presence than in the absence of the D2 agonist. U-50,488 H, at these high concentrations, was also less potent under 36-pulse than under 1-pulse stimulation conditions. From these findings, we conclude that there is only a limited interaction between presynaptic D2 autoreceptors and κ-opioid receptors on dopaminergic axon terminals in the rabbit caudate nucleus, despite they are both coupled to PTX/NEM-sensitive G-proteins.

The effects of various opioid receptor agonists and antagonists were studied in rabbit caudate nucleus slices preincubated with either [3H]dopamine or [3H]choline, superfused with medium (containing in most experiments the D2 receptor antagonist domperidone) and subjected to electrical field stimulation. The stimulation-evoked [3H]overflow from slices prelabeled with [3H]dopamine (evoked [3H]dopamine release) was significantly reduced by preferential kappa-opioid receptor agonists, like U-50,488 H, but not by mu- or delta-opioid receptor selective drugs. Opioid receptor antagonists shifted the concentration/response curve of U-50,488 H to the right (apparent pA2-value of the kappa-selective antagonist nor-binaltorphimine: 10.1) and enhanced the evoked dopamine release in the presence of a mixture of peptidase inhibitors. On the other hand, the [3H]overflow from rabbit caudate nucleus slices prelabeled with [3H]choline (evoked acetylcholine release) remained almost unaffected by any opioid receptor agonist, as long as the presynaptic D2 heteroreceptor was blocked with domperidone: in the absence of domperidone, U-50,488 H exhibited facilitatory effects. For comparison, the effects of the preferential delta-opioid receptor agonist DPDPE was also studied in slices of the rat striatum, where it clearly inhibited the evoked acetylcholine release. From our data we conclude that in the rabbit caudate nucleus the evoked dopamine release is inhibited by both exogenous and endogenous opioids via presynaptic kappa-opioid receptors, whereas the evoked release of acetylcholine is not, or only indirectly (via released dopamine) affected by opioids.

In the rabbit caudate nucleus dopamine release is inhibited by endogenous opioids via presynaptic k-opioid receptors, the release of acetylcholine is unaffected. Although pertussis toxin sensitive G-proteins appear to be involved in the mechanism of both presynaptic D2– and k-receptors on dopaminergic nerve endings, these receptors seem not to interact in their signal transduction pathways.

During carcinogenesis, pancreatic acinar cells can dedifferentiate into ductal adenocarcinoma of the pancreas. DSL-6A/C1 cells represent an in vitro model of this carcinogenic sequence. This study was designed to examine the effects of retinoids on cell growth in DSL-6A/C1 cells and to characterize further the molecular mechanisms underlying the antiproliferative actions of retinoids. Treatment of DSL-6A/C1 cells with retinoids results in a time- and dose-dependent inhibition of cell growth, paralleled by a retinoid-mediated transactivation of a pTK::betaRAREx2-luciferase reporter construct transiently transfected into DSL-6A/C1 cells. Retinoid receptor expression was evaluated by reverse transcriptase polymerase chain reaction (RT-PCR) using subtype-specific primers and demonstrated expression of retinoic acid receptor alpha (RAR-alpha), RAR-beta and retinoid X receptor alpha (RXR-alpha). Using a panel of receptor subtype-specific agonists, the RAR-alpha specific agonist Ro 40-6055 was the most potent retinoid in terms of growth inhibition. Furthermore, all-trans-retinoic acid-mediated growth inhibition and transactivation was completely blocked by the RAR-alpha-specific antagonist Ro 41-5253. In summary, the RAR-alpha subtype predominantly mediates the antiproliferative effects of retinoids in DSL-6A/C1 cells. Furthermore, this cell system provides a feasible tool to study the molecular mechanisms underlying the growth inhibitory effects of retinoids in ductal pancreatic carcinoma cells derived from a primary acinar cell phenotype. Images Figure 1 Figure 5

Hybrids ofRana ridibunda×2 unnamed Balkan taxa show no evidence, in electrophoretic comparison of soma and oocytes I for 4 enzyme loci, of germ line exclusion of their non-ridibunda genome. In this they differ from hybridsR. ridibunda×R. lessonae, ×an unnamed Italian taxon, and ×R. perezi, which in most cases clonally pass only theirridibunda genome to gametes.

Pharmacodynamic and therapeutic studies with a new slow release 240 mg verapamil formulation were performed in a total of 73 patients with essential hypertension (WHO I-II, diastolic greater than or equal to 100 mm Hg). Chronic administration of slow release 240 mg verapamil, one or two tablets in the morning, resulted in 24 h plasma concentration profiles with trough levels greater than 40 ng ml-1 in 14 of 16 patients and good 24 h blood pressure control. There was no correlation between plasma verapamil or norverapamil concentration and blood pressure response. Monotherapy with slow release verapamil was well tolerated and resulted in good blood pressure control (less than or equal to 95 mm Hg diastolic) in 46 of the 57 patients. Responses were best in older patients and those with low plasma renin or higher control blood pressure. Slow release 240 mg verapamil given once daily is a simple and effective regimen.

The mating call of ♂Pelodytes punctatus was analyzed by oscillograms and sonagrams. Above water surface, 2 types of call differing in several parameters are uttered in alternation. There is also a release call. The mating call, not uttered in series and consisting simply of uniform, short, noise-like sound pulses, seems rather undifferentiated compared with the Pelobatinae, a view supported by the more primitive habits ofPelodytes.