G protein-coupled receptor (GPR)40-dependent potentiation of insulin secretion in mouse islets is mediated by protein kinase D1.

AIMS/HYPOTHESIS: Activation of the G protein-coupled receptor (GPR)40 by long-chain fatty acids potentiates glucose-stimulated insulin secretion (GSIS) from pancreatic beta cells, and GPR40 agonists are in clinical development for type 2 diabetes therapy. GPR40 couples to the G protein subunit Gα(q/11) but the signalling cascade activated downstream is unknown. This study aimed to determine the mechanisms of GPR40-dependent potentiation of GSIS by fatty acids. METHODS: Insulin secretion in response to glucose, oleate or diacylglycerol (DAG) was assessed in dynamic perifusions and static incubations in islets from wild-type (WT) and Gpr40 (-/-) mice. Depolymerisation of filamentous actin (F-actin) was visualised by phalloidin staining and epifluorescence. Pharmacological and molecular approaches were used to ascertain the roles of protein kinase D (PKD) and protein kinase C delta in GPR40-mediated potentiation of GSIS. RESULTS: Oleate potentiates the second phase of GSIS, and this effect is largely dependent upon GPR40. Accordingly, oleate induces rapid F-actin remodelling in WT but not in Gpr40 (-/-) islets. Exogenous DAG potentiates GSIS in both WT and Gpr40 (-/-) islets. Oleate induces PKD phosphorylation at residues Ser-744/748 and Ser-916 in WT but not Gpr40 (-/-) islets. Importantly, oleate-induced F-actin depolymerisation and potentiation of GSIS are lost upon pharmacological inhibition of PKD1 or deletion of Prkd1. CONCLUSIONS/INTERPRETATION: We conclude that the signalling cascade downstream of GPR40 activation by fatty acids involves activation of PKD1, F-actin depolymerisation and potentiation of second-phase insulin secretion. These results provide important information on the mechanisms of action of GPR40, a novel drug target for type 2 diabetes.

Activation of the cardiac renin-angiotensin system and increased myocardial collagen expression in human aortic valve disease.

OBJECTIVES: We sought to determine whether the cardiac renin-angiotensin system (RAS) is activated in human aortic valve disease depending on left ventricular function, and we analyzed the concomitant regulation of the extracellular matrix components. BACKGROUND: In animal models with pressure or volume load, activation of the cardiac RAS increases fibrosis. In human aortic valve disease, the ventricular collagen protein content is increased, but only scarce data on the activation state of the cardiac RAS and its effects on collagen and fibronectin messenger ribonucleic acid (mRNA) are available. METHODS: In left ventricular biopsies from patients with aortic valve stenosis (AS) and aortic valve regurgitation and from control subjects, we quantitated mRNAs for angiotensin-converting enzyme (ACE), chymase, transforming growth factor-beta1 (TGF-beta1), collagen I, collagen III and fibronectin by reverse-transcription polymerase chain reaction. Proteins were localized by immunohistochemistry; ACE activity was determined by high performance liquid chromatography; and TGF-beta protein by quantitative enzyme immunoassay. RESULTS: Protein, ACE and TGF-beta1 mRNA were significantly increased in patients with AS and AR (1.5- to 2.1-fold) and correlated with each other. The increase occurred also in patients with normal systolic function. Collagen I and III and fibronectin mRNAs were both upregulated about twofold in patients with AS and AR. In AS, collagen and fibronectin mRNA expression levels were positively correlated with left ventricular end-diastolic pressure and inversely with left ventricular ejection fraction (LVEF). CONCLUSIONS: In human hearts, pressure and volume overload increases cardiac ACE and TGF-beta1 in the early stages. This activation of the cardiac RAS may contribute to the observed increase in collagen I and III and fibronectin mRNA expression. The increase in extracellular matrix already exists in patients with a normal LVEF, and it increases with functional impairment.

Angiotensin II directly increases transforming growth factor beta1 and osteopontin and indirectly affects collagen mRNA expression in the human heart.

OBJECTIVES: Angiotensin II (Ang II) induces fibroblast proliferation and collagen synthesis in the myocardium, but its precise mechanisms of action in human hearts are still unknown. Therefore, we investigated whether Ang II directly affects the collagen mRNA content in the human myocardium and in isolated human cardiac fibroblasts or whether the growth factors TGFbeta-1 and osteopontin are involved in this process. METHODS AND RESULTS I: In a first set of experiments, the direct effect of Ang II on collagen I, TGFbeta-1 and osteopontin mRNA content in fresh samples of human atrial myocardium was determined by the use of a short stimulation period. After 4 h, Ang II-stimulated atrial samples gave a significantly higher expression of both TGFbeta-1 (183+/-21% of control, p<0.05) and osteopontin mRNA (275+/-58%, p<0.02) than the controls. In contrast, the expression of collagen I mRNA was unchanged (95+/-8%). Stimulation with TGFbeta-1 led to an increase in collagen I and III mRNA (127+/-10%, p<0.05; 140+/-15%, p<0.02). METHODS AND RESULTS II: In a second protocol, to assess the effects of longer stimulation periods, we determined the effects of Ang II and its potential mediator TGFbeta-1 on collagen I, III and fibronectin mRNA expression and on proliferation of cultured human cardiac fibroblasts. Ang II caused a dose-dependent stimulation of proliferation but did not affect collagen I, II or fibronectin mRNA content after 24 h. In contrast, TGFbeta-1 stimulation significantly increased collagen I and III mRNA expression (124+/-5% and 128+/-5%, p<0.002). CONCLUSIONS: In the human heart, Ang II does not directly increase collagen or fibronectin mRNA, but it does increase TGFbeta-1 and osteopontin mRNA expression. Since TGFbeta-1 induces collagen I and III mRNA in atrial samples and in isolated cardiac fibroblasts, it may represent a necessary mediator of the Ang II effects in the human heart.

[Perforation of the cecum by a toothpick--a rare differential acute appendicitis diagnosis. Case report and review of the literature]. / Perforation des Coecums durch einen Zahnstocher--seltene Differentialdiagnose der akuten Appendicitis. Falldarstellung und Literaturübersicht.

We report the case of a 46-year-old man who was admitted to the medical department of the hospital Reichenbach with a 2-day history of central and upper abdominal pain. The pain was displaced in the right lower abdominal quadrant, which is why the patient was transferred to our department. At laparoscopy a toothpick was found perforating the cecum. Laparoscopic management, therapeutic possibilities and problems of diagnosis are discussed. The patient does not recall having ingested a toothpick. The laparoscopic treatment of perforation of the cecum by a toothpick might be among the rarest operations ever conducted. In the literature no such publication could be found up to now.

Myocardial angiotensin receptors in human hearts.

The cardiac renin angiotensin system (RAS) is the target for number of therapeutic interventions which proved successful in heart failure. Angiotensin converting enzyme (ACE) inhibitors belong to the most efficient strategies available and angiotensin receptor (ATR) antagonists may be comparably effective. The direct myocardial effects of both classes of substances depend on the cardiac ANG II receptors. Both subtypes, AT1 and AT2, are expressed in the human heart. AT1 is localized on myocytes, non-myocytes, vascular smooth muscle and endothelial cells, nerve endings, and conduction tissues. AT2 has so far been found in fibrous tissue and endothelial cells. AT1 mediates myocyte hypertrophy, fibroblast proliferation, collagen synthesis, smooth muscle cell growth, endothelial adhesion molecule expression, and catecholamine synthesis. AT1 is downregulated in cardiac failure as well as in the hypertrophied transplanted heart, indicating that a 50% loss of AT1 does not impede cardiac hypertrophy. In heart failure therapy, AT1 antagonists differ from ACE inhibitors by their inhibition of the degradation of bradykinin. Bradykinin has a number intrinsic effect including vasodilation, proinflammatory actions, and modulation of fibrous tissue synthesis. In addition to bradykinin, the functional role of AT2 seems crucial for the therapeutic differences of AT1 antagonists versus ACE inhibitors.

[Laparoscopic appendectomy as routine operation for treatment of inflammatory diseases of the appendix. Analysis of 733 laparoscopic appendectomies 6/1992 to 8/1997 in the Reichenbach district hospital]. / Die laparoskopische Appendektomie als Regeloperation zur Behandlung der entzündlichen Erkrankungen des Wurmfortsatzes. Analyse von 733 laparoskopischen Appendektomien des Zeitraumes von 6/1992 bis 8/1997 aus dem Kreiskrankenhaus Reichenbach.

All laparoscopic appendectomies were analysed retrospectively during 6/1992 and 8/1997 in our hospital. Operation time was 33.6 +/- 12.9 min. In 9 patients the operation had to be converted. Complications occurred in 1.77% (13 patients). 7 complications could be treated laparoscopically and 6 required a laparotomy. The hospital time was 6.4 +/- 2.2 days. The patients needed 1.3 +/- 1.7 days oral analgetics. We believe the laparoscopic appendectomy a reliable operation to treat all inflammatory diseases of the appendix.

Angiotensin receptor type 1 mRNA in human right ventricular endomyocardial biopsies: downregulation in heart failure.

OBJECTIVE: Atrial angiotensin II receptors type 1 (AT1) are downregulated in end-stage human heart failure at mRNA and protein level. The present study investigated whether AT1 ventricular mRNA content was reduced in myocardial biopsies from heart failure patients. METHODS: AT1 mRNA was quantitated in right ventricular endomyocardial biopsies from 16 patients with decreased left ventricular function (LVEF 36 +/- 3%) due to dilated cardiomyopathy (DCM) and in biopsies from 12 patients with suspected myocardial disease but normal cardiac function (LVEF 62 +/- 2%). Two biopsies per patient were pooled, RNA was extracted and reverse-transcribed after addition of an AT1 cRNA standard. AT1 standard and wild-type RNA were amplified with the same primers in the same PCR tube. The PCR products were hybridized to a microtiter plate and detected and quantitated by an ELISA system. Glyceraldehyde phosphate dehydrogenase (GAPDH) mRNA was determined in the same samples as AT1 mRNA. RESULTS: In the biopsies from 16 patients with heart failure, a 68% decrease in AT1 mRNA content was found in comparison with 12 controls (heart failure 94 +/- 15 AT1 mRNA copies/ng RNA; controls 297 +/- 45; P < 0.001). Relating AT1 mRNA content to GAPDH mRNA confirmed the specific decrease in AT1 mRNA (AT1/GAPDH: heart failure 1.3 +/- 0.15; controls 3.4 +/- 0.5; p < 0.002). The best correlation between AT1 mRNA content and clinical parameters was found for right ventricular ejection fraction (r = 0.59, P < 0.01). CONCLUSIONS: The quantitative RT-PCR procedure indicated a loss of ventricular AT1 mRNA in human heart failure which corresponds to the loss of AT1 protein described previously. It may underlie the decrease in AT1 protein expression in human heart failure.

Decreased expression of ventricular angiotensin receptor type 1 mRNA after human heart transplantation.

Myocardial angiotensin receptors of type 1 (AT1) are downregulated at the protein and mRNA levels in human heart failure. No data are available for the transplanted human heart, which frequently exhibits functional alterations. The aim of the present study was the quantitation of ventricular AT1 mRNA content in endomyocardial biopsies from patients after heart transplantation. For the determination of AT1 mRNA we used a novel quantitative reverse transcription polymerase chain reaction with low variance (6%) based on an internal AT1 cRNA standard, liquid-phase hybridization of polymerase chain reaction products in microtiter plates, and quantitation by enzyme-linked immunosorbent assay. Right ventricular biopsies from 16 patients after heart transplantation (left ventricular ejection fraction 67 +/- 7%) were compared with 12 patients with normal cardiac function (left ventricular ejection fraction 62 +/- 5%). A 46% lower AT1 mRNA content was found in biopsies from the 16 patients after heart transplantation than in the 12 controls (heart transplantation, 200 +/- 25 AT1 mRNA copies/ng RNA; controls, 368 +/- 50; P < 0.01). When AT1 mRNA content was related to the stably expressed GAPDH mRNA, a 49% decrease was detected (AT1/GAPDH: patients, 2.4 +/- 0.25; controls, 4.7 +/- 0.6; P < 0.006). No association between the extent of AT1 downregulation and clinical or hemodynamic variables was detected. In the human heart ventricular AT1 is downregulated after orthotopic heart transplantation. The decrease in AT1 mRNA is not associated with altered systolic function. This may partially reflect a loss of autonomic nerves and thus altered nervous control of the heart.

[Development of gynecologic endoscopy in Germany--a statistical overview 1989 to 1993]. / Die Entwicklung der gynäkologischen Endoskopie in Deutschland--eine statistische Erhebung der Jahre 1989 bis 1993.

The first statistical report on pelvioscopy/laparoscopy of total Germany covers a five years period from 1989, 01.01 to 1993 31.12. It includes a total of 461,568 pelvioscopies/laparoscopies from 374 hospitals and 52,861 pelvioscopies/laparoscopies from 116 medical practitioners. Hospitals' response rate was 43% with 99.2% reporting pelvioscopy/laparoscopy. The response rate of medical practitioners was 41% with 97.4% performing same methods. During the five year period of survey, hospitals reported a total of 2095 serious complications requiring laparotomy or control laparoscopy (complication rate = 4.5/1000). Medical practitioners reported a total of 197 serious complications (complication rate = 3.7/1000). Compared with the data of the fourth statistical survey of laparoscopy (1986 to 1988) there is a remarkable increase in serious complications. Most of them are mechanical lesions of blood vessels in the abdominal wall or in the mesosalpinx, followed by mechanical lesions of the intestine. Also remarkable is the observation that pelvioscopy/laparoscopy as surgical method is continuously increasing. As shown in previous statistics on pelvioscopy for tubal sterilization the bipolar technique is the most popular one for both hospitals and medical practitioners. It is followed by endocoagulation after Semm whereas mechanical techniques are of little importance. The monopolar high frequency current is still used in 9.6% by hospitals and 8.8% by medical practitioners, with and without transsection. Sterilization failure rate remains nearly at the same levels as it was reported previously: 1.6/1000 in hospitals and 3.7/1000 in private practices. The highest failure rate was observed after the use of monopolar HF-techniques. 82.5% of the hospitals and 65% of the medical practitioners reported tendency in performing endoscopy by surgery is continuously increasing.