[Effect of splenectomy on the risk of hepatocellular carcinoma development among patients with liver cirrhosis and portal hypertension: a multi-institutional cohort study].

Objective: To identify whether splenectomy for treatment of hypersplenism has any impact on development of hepatocellular carcinoma(HCC) among patients with liver cirrhosis and hepatitis. Methods: Patients who underwent splenectomy for hypersplenism secondary to liver cirrhosis and portal hypertension between January 2008 and December 2012 were included from seven hospitals in China, whereas patients receiving medication treatments for liver cirrhosis and portal hypertension (non-splenectomy) at the same time period among the seven hospitals were included as control groups. In the splenectomy group, all the patients received open or laparoscopic splenectomy with or without pericardial devascularization. In contrast, patients in the control group were treated conservatively for liver cirrhosis and portal hypertension with medicines (non-splenectomy) with no invasive treatments, such as transjugular intrahepatic portosystemic shunt, splenectomy or liver transplantation before HCC development. All the patients were routinely screened for HCC development with abdominal ultrasound, liver function and alpha-fetoprotein every 3 to 6 months. To minimize the selection bias, propensity score matching (PSM) was used to match the baseline data of patients among splenectomy versus non-splenectomy groups. The Kaplan-Meier method was used to calculate the overall survival and cumulative incidence of HCC development, and the Log-rank test was used to compare the survival or disease rates between the two groups. Univariate and Cox proportional hazard regression models were used to analyze the potential risk factors associated with development of HCC. Results: A total of 871 patients with liver cirrhosis and hypertension were included synchronously from 7 tertiary hospitals. Among them, 407 patients had a history of splenectomy for hypersplenism (splenectomy group), whereas 464 patients who received medical treatment but not splenectomy (non-splenectomy group). After PSM,233 pairs of patients were matched in adjusted cohorts. The cumulative incidence of HCC diagnosis at 1,3,5 and 7 years were 1%,6%,7% and 15% in the splenectomy group, which was significantly lower than 1%,6%,15% and 23% in the non-splenectomy group (HR=0.53,95%CI:0.31 to 0.91,P=0.028). On multivariable analysis, splenectomy was independently associated with decreased risk of HCC development (HR=0.55,95%CI:0.32 to 0.95,P=0.031). The cumulative survival rates of all the patients at 1,3,5,and 7 years were 100%,97%,91%,86% in the splenectomy group,which was similar with that of 100%,97%,92%,84% in the non-splenectomy group (P=0.899). In total,49 patients (12.0%) among splenectomy group and 75 patients (16.2%) in non-splenectomy group developed HCC during the study period, respectively. Compared to patients in non-splenectomy group, patients who developed HCC after splenectomy were unlikely to receive curative resection for HCC (12.2% vs. 33.3%,χ²=7.029, P=0.008). Conclusion: Splenectomy for treatment of hypersplenism may decrease the risk of HCC development among patients with liver cirrhosis and portal hypertension.

[Is the discipline associated with self-confidence in handling rational antibiotic prescription? : Results from the MR2 study in German hospitals]. / Ist die Fachrichtung assoziiert mit der Selbstsicherheit im Umgang mit rationaler Antibiotikaverordnung? : Ergebnisse der MR2-Studien an deutschen Kliniken.

BACKGROUND: Besides public awareness and specialist knowledge and training of physicians, their self-confidence plays a key role for clinical decision-making in the respective area. OBJECTIVE: This exploratory study investigated the influence of the discipline on differences in self-confidence in dealing with antibiotics and in the self-rated knowledge. METHODS: In 2015 the multi-institutional reconnaissance of practice with multiresistant bacteria (MR2) questionnaire containing items on antibiotic prescription and multiresistant pathogens was sent out to 1061 physicians working in departments for internal medicine, general surgery, gynecology and obstetrics and urology. In 2017 a similar MR2 survey was sent to 1268 specialist and assistant physicians in anesthesiology in Germany. Besides demographic data 4 items on self-confidence in the use of antibiotic treatment and 11 items concerning self-rated knowledge about rational antibiotic therapy and multiresistant pathogens were included in the present analysis. Logistic regression analysis, the χ2-test and the Kruskal-Wallis test were used for statistical analysis of the influence of the discipline on these items. RESULTS: The response rates were 43% (456 out of 1061) from the non-anesthetists and 56% (705 out of 1268) from the anesthetists. Of the non-anesthetists 44% and 57% of the anesthetists had had no advanced training on antibiotic stewardship during the year before the study. In the overall analysis anesthetists (mean±SD: 2.53±0.54) were significantly less self-confident about antibiotics than colleagues from other departments (internal medicine: 3.10±0.50, general surgery: 2.97±0.44, gynecology and obstetrics: 3.12±0.42 and urology: 3.15±0.44) in the unadjusted (all p<0.001) and adjusted comparison. The analysis of self-rated knowledge about rational antibiotic prescription showed similar results. Senior consultant status and advanced training in infectiology were significantly associated with self-confidence and self-rated knowledge about antibiotics. CONCLUSION: Anesthetists showed significantly less self-confidence in dealing with antibiotics than colleagues from other disciplines. Advanced training on a rational prescription of antibiotics was associated with a greater self-confidence, so that the implementation of compulsory courses on rational antibiotic stewardship in the respective residency curriculum needs to be considered.

Lysosomal dysfunction in the brain of a mouse model with intraneuronal accumulation of carboxyl terminal fragments of the amyloid precursor protein.

Recent data suggest that intraneuronal accumulation of metabolites of the amyloid-ß-precursor protein (APP) is neurotoxic. We observed that transgenic mice overexpressing in neurons a human APP gene harboring the APPE693Q (Dutch) mutation have intraneuronal lysosomal accumulation of APP carboxylterminal fragments (APP-CTFs) and oligomeric amyloid ß (oAß) but no histological evidence of amyloid deposition. Morphometric quantification using the lysosomal marker protein 2 (LAMP-2) immunolabeling showed higher neuronal lysosomal counts in brain of 12-months-old APPE693Q as compared with age-matched non-transgenic littermates, and western blots showed increased lysosomal proteins including LAMP-2, cathepsin D and LC3. At 24 months of age, these mice also exhibited an accumulation of α-synuclein in the brain, along with increased conversion of LC3-I to LC3-II, an autophagosomal/autolysosomal marker. In addition to lysosomal changes at 12 months of age, these mice developed cholinergic neuronal loss in the basal forebrain, GABAergic neuronal loss in the cortex, hippocampus and basal forebrain and gliosis and microgliosis in the hippocampus. These findings suggest a role for the intraneuronal accumulation of oAß and APP-CTFs and resultant lysosomal pathology at early stages of Alzheimer's disease-related pathology.

A new approach for fat removal in a discontinuous autotransfusion device-concept and evaluation.

BACKGROUND: Fat present during blood salvage in orthopaedic or cardiac surgery can pose a risk of fat embolism and should be eliminated before transfusion. Based on observations of central fat accumulation at the bottom of Latham bowls, a fat reduction program was developed using two volume displacements, where blood temporarily is removed and respun in the bowl to force the fat through the RBC sediment. MATERIALS AND METHODS: Pooled ABO-matched RBC and FFP were adjusted to a haematocrit of 10%, and human fat tissue added to a concentration of 1·25 vol%. In six experiments, blood was processed with the new-generation cell salvage device CS Elite in a newly developed fat reduction program in bowls of three sizes. Volumetric quantification of fat was performed after centrifugation of blood samples in Pasteur pipettes. From volumes, haematocrits and the concentrations of fat, RBC recovery and fat elimination rates were calculated. RESULTS: Fat removal rates of 93·2 ± 2·8, 97·0 ± 2·1 and 99·6 ± 0·3% were observed with a 70-ml, 125-ml and 225-ml bowl, respectively, and even higher rates when removal rates were calculated one cycle. At the same time, high RBC recovery and plasma elimination rates were maintained, not significantly different to the default program mode. CONCLUSION: Modifications in process parameters and sequence led to a fat reduction program that significantly improves fat removal with the Cell Saver Elite from 77·4 ± 5·1% in the default mode to an average of 98·6 ± 1·1%, yielding results equivalent to the continuous cell salvage system (C.A.T.S).

Performance of a new-generation continuous autotransfusion device including fat removal and consequences for quality controls.

BACKGROUND AND OBJECTIVES: Cell salvage plays a key role in blood conservation. To maintain high performance, quality management is recommended. Accordingly, a new-generation autotransfusion device was tested for its performance and compared with its predecessor. Two different calculations of quality parameters were applied. MATERIALS AND METHODS: In an experimental study, the continuous autotransfusion devices CATSmart and Continuous Autotransfusion System (C.A.T.S) plus were tested using banked blood adjusted to a haematocrit of 20% and anticoagulated with heparin 5 U/L. Test blood was processed using an emergency programme, a high-quality programme/smart wash programme and a low-volume wash programme. Samples were taken after the production of 200 mL of red blood cells (RBC) and after the final emptying of the separation chamber. In an additional set of tests, blood containing 1·25% fat was processed with both devices to examine fat removal. RESULTS: Both devices demonstrated an equally high performance with regards to product hematocrit (Hct); RBC recovery; and elimination rates of protein, heparin and fat. The high fat elimination rate (>99·8%) reported for C.A.T.S plus was confirmed for CATSmart, regardless of the used programme. Samples taken during the ongoing process show a higher haematocrit and RBC recovery rate than samples taken after the final emptying of the separation chamber. Interface sensors were not affected by fat in the blood. CONCLUSIONS: The new-generation autotransfusion device CATSmart is not inferior to its predecessor and shows high performance with regards to RBC recovery, plasma and fat elimination in all programme modes. Samples for quality controls should be taken during blood processing.

The effect of intra- and postoperative allogenic blood transfusion on patients' survival undergoing radical cystectomy for urothelial carcinoma of the bladder.

PURPOSE: Radical cystectomy (RC) can be associated with significant blood loss. Allogenic blood transfusion (ABT) may alter disease outcome because of a theoretical immunomodulatory effect. We evaluated the effects of ABT on overall survival (OS) and progression-free survival (PFS) of patients undergoing RC for urothelial carcinoma of the bladder (UCB). MATERIALS AND METHODS: This is a retrospective single-center study of 350 consecutive patients of a university health center with a median follow-up of 70.1 month. All patients underwent RC and pelvic lymph node dissection. The effect of ABT on OS and PFS was analyzed using univariable and multivariable Cox proportional hazards models. RESULTS: The overall ABT rate was 63 % (n = 219), with intraoperative blood transfusion and postoperative blood transfusion being performed in 183 patients (52 %) and 99 patients (28 %), respectively. Preoperative anemia was detected in 156 patients (45 %) with median estimated blood loss of 800 ml (IQR: 500-1,200). ABT was associated with significant decrease of OS and PFS in multivariable analyses (p < 0.001), whereas patients' prognosis worsened the more packed red blood cells (PRBC) were transfused (p < 0.001). The study is limited in part due to its retrospective design. CONCLUSIONS: We found that ABT and the number of PRBC transfused are associated with poor prognosis for UCB patients undergoing RC, whereas preoperative anemia had no influence on survival. This emphasizes the importance of surgeon's awareness for a strict indication for ABT. A prospective study will be necessary to evaluate the independent risks associated with ABT during surgical treatments.

XY gonadal dysgenesis--development of a germ cell tumor: case report.

Gonadal dysgenesis (GD) is a rare congenital malformation that affects about one in 3,000 births. The authors present a case of a 17-year-old woman with primary amenorrhea and poor breast development. They conducted a laparoscopic surgery and bilaterally removed hypoplastic streak gonads. Histopathology of the ovaries revealed bilateral streak gonads with gonadoblastomas and a right-sided dysgerminoma.

[Inpatient pain consultation service at a university hospital: a retrospective analysis of patient characteristics and the rate of the implementation of recommendations]. / Stationäre Schmerzkonsile einer universitären Schmerzambulanz : Eine retrospektive Analyse der Patientencharakteristika und der Umsetzungsrate der Empfehlungen.

BACKGROUND: The aim of this study was to conduct an audit of a university inpatient pain consultation service and to examine the quality and the implementation of the recommended therapeutic measures. Factors that influenced the implementation should be identified. PATIENTS AND METHODS: All inpatients treated by the consultation service in the years 2009 and 2010 were analyzed retrospectively. Demographic patient characteristics as well as quality parameters of the consultation service and pharmacological and non-pharmacological recommendations and their implementation were analyzed. RESULTS: In total 1,048 requests for the consultation service were processed of which 39.7% of the requests were for patients with acute pain, 33.8% with chronic and 19.9% with tumor-associated pain. Measures recommended most were medication, physiotherapy and psychological treatment. Recommended medications were actually prescribed in more than 80%, physiotherapy recommended in about 75% and psychological treatment recommended in 47% of the cases. Only a few influencing factors for the implementation of the recommended measures could be identified. CONCLUSION: Many different pain states are seen in an inpatient pain consultation service. The recommendations given are implemented in most cases especially concerning the medication.

Effect of HBO therapy on adipose-derived stem cells, fibroblasts and co-cultures: In vitro study of oxidative stress, angiogenic potential and production of pro-inflammatory growth factors in co-cultures1.

BACKGROUND: A key moderator of wound healing is oxygen. Wound healing is a dynamic and carefully orchestrated process involving blood cells, cytokines, parenchymal cells (i.e. fibroblasts and mesenchymal stem cells) and extracellular matrix reorganization. Human adipose derived stem cells as well as human fibroblasts produce soluble factors, exhibit diverse effects on inflammation and anti inflammation response and are involved in wound healing processes.Hyperbaric oxygen therapy is an effective adjunct treatment for ischemic disorders such as chronic infection or chronic wounds. In vitro effects of hyperbaric oxygen therapy on human cells were presented in many studies except for those on mono- and co-cultures of human adipose derived stem cells and fibroblasts. OBJECTIVE: The aim of this study was to investigate the effects of hyperbaric oxygen therapy on mono- and co-cultures of human adipose derived stem cells and fibroblasts. METHODS: Mono- and co-cultures from human adipose derived stem cells and fibroblasts were established. These cultures were exposed to hyperbaric oxygen therapy every 24 h for five consecutive days. Measuring experiments were performed on the first, third and fifth day. Therapy effects on the expression of VEGF, IL 6 and reactive oxygen species were investigated. RESULTS: After exposure to hyperbaric oxygen, cell culturess showed a significant increase in the expression of VEGF after 3 and 5 days. All cultures showed significantly reduced formation of reactive oxygen species throughout the experiments. The expression of IL-6 decreased during the experiment in mono-cultures of human adipose derived stem cells and co-cultures. In contrast, mono-cultures of human skin fibroblasts showed an overall significantly increased expression of IL-6. CONCLUSIONS: Hyperbaric oxygen therapy leads to immunmodulatory and proangiogenetic effects in a wound-like enviroment of adipose derived stem cells and fibroblasts.

Vasopressor support vs. liberal fluid administration in deep inferior epigastric perforator (DIEP) free flap breast reconstruction - a randomized controlled trial.

BACKGROUND: Perioperatively, patients' hemodynamics are modulated predominantly by intravenous fluid administration and vasoactive pharmacological support. Vasopressor agents are suspected to be detrimental on free flap survival by the cause of vasoconstriction of the pedicle with consecutive reduced overall flap perfusion and by aggravation of flap dissection. OBJECTIVE: A novel, standardized fluid restrictive perioperative hemodynamic management was assessed for its feasibility in clinical practice in free flap patients undergoing breast reconstruction. METHODS: Patients were randomized to two perioperative regimens with different fluid and vasopressor limits. The primary endpoint regarded flap survival. Secondary endpoints included surgery times, time of patient ambulation and length of hospital stay. RESULTS: There was one total flap failure with liberal fluid administration (LFA). No total or partial flap failure was noted in the fluid restrictive regimen with norepinephrine administration up to 0.04µg/kg/min (FRV). No delay regarding operation time (p = 0.217), patient mobilization (p = 0.550) or hospital discharge (p = 0.662) was registered in the FRV study subpopulation compared to LFA. CONCLUSIONS: The results of this prospective interventional trial could not detect any negative impact of vasopressors, neither for the primary endpoint of flap survival nor for the overall patient outcome. The fear of vasopressor associated flap complications has led to a traditional liberal fluid administration, which failed to demonstrate any benefits when compared to a fluid restrictive vasopressor strategy.

Involvement of sensory afferent fibers and lipid peroxidation in the pathogenesis of stress-induced gastric mucosa damage.

Ablation of sensory nerves impairs healing of gastric ulcers, but the role of free radicals in the healing process has been little studied. The aim of our present investigations was to determine the participation of reactive oxygen species (ROS) in sensory nerve activity during WRS. Experiments were carried out on male Wistar rats and the number of gastric lesions was measured by planimetry. Colorimetric assays were used to determine gastric mucosal levels of malondialdehyde (MDA) and 4-hydroxynonenal (4-HNE), as well as superoxide dismutase (SOD) activity. We found that capsaicin-inactivation of sensory nerves resulted in magnification of gastric mucosal damage induced by the WRS. In this process, oxidative stress occurs, as reflected by an increase of MDA and 4-HNE tissue concentrations (an index of lipid peroxidation), and a decrease of SOD activity, could play an important role. Pentoxyfilline-induced gastroprotection and hyperemia depends upon attenuation of the oxidative stress. This protection and hyperemia were, at least in part, attenuated by ASA. Afferent sensory fibers participate in the pathogenesis of ulcers. Lipid peroxidation plays an important role in this process.

Protective influence of melatonin against acute esophageal lesions involves prostaglandins, nitric oxide and sensory nerves.

Melatonin (MT) is known to protect gastrointestinal mucosa against various types of injury but its effects on esophageal damage have not been studied. We examined the effects of MT on acute esophageal injury and the mechanism involved in the action of this indole. Acute esophageal lesions were induced by perfusion with acid-pepsin solution using tube inserted through the oral cavity into the mid of esophagus of anaesthetized rats with or without inhibition of prostaglandin (PG) generation by indomethacin (5 mg/kg/day), nitric oxide (NO) formation by N(G)-nitro-L-arginine (L-NNA, 20 mg/kg/day) or sensory nerves deactivation by capsaicin (125 mg/kg, sc). The esophageal injury was assessed by macroscopic score and histologic activity index. The esophageal mucosal blood flow (EBF) was determinated by H(2)-gas clearance method. The plasma TNF-alpha and nitrate/nitrite (NOx) levels and mucosal PGE(2) contents were assessed by immunoassays. Esophageal acid-pepsin perfusion induced noticeable esophageal mucosal injury as compared to perfusion with vehicle saline. The pretreatment with MT prevented significantly esophageal injury, raised EBF and mucosal content of PGE(2), while decreasing the levels of TNF-alpha. Inhibition of COX/PG and NOS/NO systems by indomethacin and L-NNA, respectively, or inactivation of sensory nerves by capsaicin, that manifested in further increase of esophageal injury, reduced the levels of EBF, markedly raised the levels TNF-alpha and reduced mucosal PGE(2), but the pretreatment with MT prevented significantly esophageal injury, improved EBF and raised mucosal PGE(2) contents. These studies suggest that MT can be considered as a novel esophagoprotector, acting, at least in part, through the COX/PG and NOS/NO systems and activation of sensory nerves.

Role of circadian rhythm and endogenous melatonin in pathogenesis of acute gastric bleeding erosions induced by stress.

Stress that appears as a consequence of burns, surgical trauma and life threatening conditions is a serious clinical entity, can result in acute gastric mucosal lesions. Such stress lesions can develop in response to the imbalance between the aggressive factors promoting mucosal damage and the gastric mucosal defense mechanisms including predominantly gastric blood flow (GBF), biosynthesis of gastroprotective prostaglandins (PG) and enhanced mucus/bicarbonate secretion. Melatonin, a major hormone of pineal gland, whose activity is also abundant in the gastrointestinal tract, was shown to inhibit gastric acid secretion, augment GBF and scavenge free radicals, resulting in the attenuation of stress-induced gastric lesions. Melatonin is released during the night but little is known about the effect of circadian rhythm and day/night alterations in melatonin secretion on the formation of stress-induced gastric lesions. Using rats with intact pineal glands and those with removed pineal glands (pinealectomy) exposed to water immersion and restraint stress (WRS) at both, day and night hours, we studied the effect of light and nocturnal melatonin on the formation of these lesions, and accompanying changes in GBF and plasma melatonin levels. It was found that the gastric mucosa exposed to WRS of various time duration's lasting 1.5, 3 and 6 h, time-dependently increased the number of gastric lesions and this effect was accompanied by the time-dependent fall in the GBF and an increase in the plasma and luminal melatonin levels. Pinealectomy augmented WRS-induced lesions at each time intervals of WRS and produced a marked fall in the GBF and plasma and luminal melatonin levels at each time interval of WRS tested. WRS lesions were significantly reduced at night hours and showed circadian variations in plasma levels melatonin with significantly higher plasma melatonin levels at night than in the day and with a greater magnitude of damage induced in the daily hours than at night hours. WRS-induced gastric mucosal lesions were markedly enhanced in pinealectomized rats, both at day and night, and this was accompanied by a significant fall in plasma melatonin levels Stress that appears as a consequence of burns, surgical trauma and life threatening conditions is a serious clinical entity, can result in acute gastric mucosal lesions. Such stress lesions can develop in response to the imbalance between the aggressive factors promoting mucosal damage and the gastric mucosal defense mechanisms including predominantly gastric blood flow (GBF), biosynthesis of gastroprotective prostaglandins (PG) and enhanced mucus/bicarbonate secretion. Melatonin, a major hormone of pineal gland, whose activity is also abundant in the gastrointestinal tract, was shown to inhibit gastric acid secretion, augment GBF and scavenge free radicals, resulting in the attenuation of stress-induced gastric lesions. Melatonin is released during the night but little is known about the effect of circadian rhythm and day/night alterations in melatonin secretion on the formation of stress-induced gastric lesions. Using rats with intact pineal glands and those with removed pineal glands (pinealectomy) exposed to water immersion and restraint stress (WRS) at both, day and night hours, we studied the effect of light and nocturnal melatonin on the formation of these lesions, and accompanying changes in GBF and plasma melatonin levels. It was found that the gastric mucosa exposed to WRS of various time duration's lasting 1.5, 3 and 6 h, time-dependently increased the number of gastric lesions and this effect was accompanied by the time-dependent fall in the GBF and an increase in the plasma and luminal melatonin levels. Pinealectomy augmented WRS-induced lesions at each time intervals of WRS and produced a marked fall in the GBF and plasma and luminal melatonin levels at each time interval of WRS tested. WRS lesions were significantly reduced at night hours and showed circadian variations in plasma levels melatonin with significantly higher plasma melatonin levels at night than in the day and with a greater magnitude of damage induced in the daily hours than at night hours. WRS-induced gastric mucosal lesions were markedly enhanced in pinealectomized rats, both at day and night, and this was accompanied by a significant fall in plasma melatonin levels with a pronounced reduction in mucosal generation of PGE(2) and GBF and by a small increase in plasma melatonin levels during the dark phase. We conclude that 1) stress-induced gastric bleeding erosions exhibit circadian rhythm with an increase in the day and attenuation at night and that these fluctuations in the formation of stress-induced gastric damage may depend upon the melatonin synthesis 2) the progressive increase in plasma melatonin in pinealectomized animals exposed to various time intervals of WRS suggests that extra-pineal melatonin possibly that derived from gastrointestinal tract, play an important role in the gastric mucosal defense against stress-induced gastric damage.

Localization and biological activities of melatonin in intact and diseased gastrointestinal tract (GIT).

Melatonin (MT), an indole formed enzymatically from L-trytophan (Trp), was first discovered in the bovine pineal gland in 1958 by Lerner et al. Melatonin is the most versatile and ubiquitous hormonal molecule produced not only in the pineal gland but also in various other tissues of invertebrates and vertebrates, particularly in the gastrointestinal tract (GIT). This review focuses on the localization, production, metabolism and the functions of MT in GIT and the duodenal unit (liver, biliary routes and pancreas), where multi-step biosynthetic pathways of this indole, similar to those in pinealocytes, have been identified. These biosynthetic steps of MT, including two major rate limiting enzymes; arylalkylamine-N-acetyltransferase (AA-NAT) and hydroxyindole-O-methyltransferase (HIOMT), transforming L-tryptophan (Trp), originally identified in pinealocytes, have been also detected in entero-endocrine (EE) cells of GIT, where this indole appears to act in endocrine, paracrine and/or luminal pathway directly or through G-protein coupled MT receptors. Studies of the distribution of MT in GIT mucosa showed that this indole is generated in GIT in much larger amounts than it is produced in the pineal gland. Melatonin acts in GIT, partly locally in paracrine fashion and is partly released into portal circulation, to be taken up by the liver. It is then metabolized and excreted with the bile to small bowel and finally returns to liver through entero-hepatic circulation. The production of MT by the pineal gland shows circadian rhythm with high night-time surge, especially at younger age, followed by the fall during the day-light time. As a highly lipophylic substance, MT reaches all body cells within minutes, thus, serving as a convenient circadian timing signal. Following pinealectomy, the light/dark cycle of plasma MT levels disappears, while its day-time blood concentration is maintained mainly due to its release from the GIT. According to our experience, after oral application of Trp, the plasma MT increases in dose-dependent manner both in intact and pinealectomized animals and humans, indicating that GIT but not the pineal gland is a source of this indole. In GIT MT exhibits a wide spectrum of activities such as circadian entrainment, antioxidant and free radicals scavenging activity, Melatonin (MT), an indole formed enzymatically from L-trytophan (Trp), was first discovered in the bovine pineal gland in 1958 by Lerner et al. Melatonin is the most versatile and ubiquitous hormonal molecule produced not only in the pineal gland but also in various other tissues of invertebrates and vertebrates, particularly in the gastrointestinal tract (GIT). This review focuses on the localization, production, metabolism and the functions of MT in GIT and the duodenal unit (liver, biliary routes and pancreas), where multi-step biosynthetic pathways of this indole, similar to those in pinealocytes, have been identified. These biosynthetic steps of MT, including two major rate limiting enzymes; arylalkylamine-N-acetyltransferase (AA-NAT) and hydroxyindole-O-methyltransferase (HIOMT), transforming L-tryptophan (Trp), originally identified in pinealocytes, have been also detected in entero-endocrine (EE) cells of GIT, where this indole appears to act in endocrine, paracrine and/or luminal pathway directly or through G-protein coupled MT receptors. Studies of the distribution of MT in GIT mucosa showed that this indole is generated in GIT in much larger amounts than it is produced in the pineal gland. Melatonin acts in GIT, partly locally in paracrine fashion and is partly released into portal circulation, to be taken up by the liver. It is then metabolized and excreted with the bile to small bowel and finally returns to liver through entero-hepatic circulation. The production of MT by the pineal gland shows circadian rhythm with high night-time surge, especially at younger age, followed by the fall during the day-light time. As a highly lipophylic substance, MT reaches all body cells within minutes, thus, serving as a convenient circadian timing signal. Following pinealectomy, the light/dark cycle of plasma MT levels disappears, while its day-time blood concentration is maintained mainly due to its release from the GIT. According to our experience, after oral application of Trp, the plasma MT increases in dose-dependent manner both in intact and pinealectomized animals and humans, indicating that GIT but not the pineal gland is a source of this indole. In GIT MT exhibits a wide spectrum of activities such as circadian entrainment, antioxidant and free radicals scavenging activity, cytoprotective, anti-inflammatory and healing efficacy of various GIT lesions such as esophagitis, gastritis, peptic ulcer, pancreatitis and colitis. This review concentrates on the generation and pathophysiological implication of MT in GIT and related organs.

The renin-angiotensin system and its vasoactive metabolite angiotensin-(1-7) in the mechanism of the healing of preexisting gastric ulcers. The involvement of Mas receptors, nitric oxide, prostaglandins and proinflammatory cytokines.

The inhibition of angiotensin-converting enzyme (ACE) or the blockade of angiotensin (Ang) AT-1 receptors affords protection against acute gastric mucosal injury, but whether the major metabolite of renin-angiotensin system (RAS), Ang-(1-7), accelerates the healing process of preexisting gastric ulcers remains unknown. Previous studies documented that Ang-(1-7) acting via its own Mas receptor exerts vascular responses opposing those of Ang II. We studied the effects of the Ang-(1-7)/Mas receptor axis on the healing rate of acetic-acid-induced gastric ulcers with or without the blockade of Mas receptors by A 779 and compared it with the effects of activation and blockade of the AT-1 receptor by the treatment with Ang II and losartan, respectively, the inhibition of ACE by lisinopril, the NO/cNOS inhibition by L-NAME and inhibition of prostaglandin/COX system by indomethacin in the presence of Ang-(1-7). Additionally, ex vivo metabolism of Ang I in gastric tissue was assessed by LC/MS method. At day 9 after ulcer induction, the area of these ulcers and the accompanying changes in total gastric blood flow (GBF) were determined as were gastric mucosal blood flow (GMBF) at ulcer margin and gastric oxygen uptake (GVO2). The gastric mucosal expression of mRNAs for constitutive nitric oxide synthase (cNOS), superoxide dismutase (SOD), and pro-inflammatory cytokines interleukin 1ß (IL-1ß) and tumor necrosis factor alpha (TNF-α) and plasma level of both cytokines were determined by RT-PCR and ELISA. The 9 days treatment with Ang II dose-dependently increased the area of gastric ulcers and this effect was accompanied by a significant fall in the GBF, GVO2 and GMBF at ulcer margin. In contrast, treatment with Ang-(1-7) which produced a significant rise in the luminal content of NO significantly reduced the area of gastric ulcer and significantly increased the GBF, GVO2 and the GMBF at ulcer margin. Similar GMBF changes and significant reduction the area of gastric ulcer was observed in rats with gastric ulcers treated with the agonist of Mas receptor, AVE 0991. These effects of Ang-(1-7) and AVE 0991 were eliminated by blockade of the Mas receptor with A779. Similarly to Ang-(1-7), treatment with losartan or lisinopril significantly reduced the area of gastric ulcers and the accompanying increase in the GMBF at ulcer margin and these effects were significantly attenuated by a concomitant administration of L-NAME and indomethacin. The rate of healing of ulcers was associated with a decrease in ex vivo Ang-(1-7) formation and this effect was attenuated by lisinopril. The treatment with Ang-(1- 7) or AVE 0991 increased the expression of mRNA for cNOS and SOD and downregulated that of IL-1ß and TNF-α followed by the decrease in the plasma IL-1ß and TNF-α levels. We conclude that the Ang-(1-7)/Mas receptor system accelerates the healing of preexisting gastric ulcers via an increase in the gastric macro- and microcirculations, and an increase in gastric tissue oxygenation. These effects are mediated by PG and NO derived from overexpression of cNOS, an increase in the expression of antioxidizing enzyme SOD 2 and an anti-inflammatory action involving the inhibition of expression and release of pro-inflammatory cytokines IL-1ß and TNF-α. Our results seem to underlie the importance of the Ang-(1-7), AT-1 and Mas receptors in the regulation of local vascular and metabolic effects associated with mechanism of gastric ulcer healing.

Preoperative anemia is associated with adverse outcome in patients with urothelial carcinoma of the bladder following radical cystectomy.

PURPOSE: Radical cystectomy (RC) can be associated with significant blood loss, whereas many patients are presenting with anemia preoperatively. To date, there is a lack of data addressing the impact of preoperative anemia (PA) on survival of patients undergoing RC for urothelial carcinoma of the bladder (UCB). METHODS: This retrospective multicenter study includes 684 patients with UCB undergoing RC with pelvic lymph node dissection. The median follow-up was 50 (IQR 29,78) months. Anemia was defined in line with the WHO classification (hemoglobin (Hb): male ≤13 g/dL, female ≤12 g/dL) and based on contemporary gender- and age-adjusted classification (Hb: white male aged <60 years: ≤13.7 g/dL; ≥60 years: ≤13.2 g/dL; white female of all ages ≤12.2 g/dL). Univariable and multivariable Cox regression analyses were used to assess the effects of PA on oncological outcomes. RESULTS: A total of 269 (39.3 %) and 302 (44.2 %) patients were anemic according to the WHO classification versus contemporary classification. Age, increased ECOG performance status, advanced tumor stages, lymph node metastasis, positive surgical margin and anemia were associated with disease recurrence (DR), cancer-specific mortality (CSM) and all-cause mortality (ACM). In multivariable analysis, anemia was an independent predictor of DR, CSM and ACM (WHO and/or contemporary classification). Blood transfusion was significantly associated with ACM in both classifications of anemia. CONCLUSIONS: PA is significantly associated with worse oncological outcome in patients undergoing RC. Based on the additional unfavorable influence of blood transfusion, this emphasizes the importance of early diagnosis and correction of anemia and implementation of alternative methods of blood volume management.

Primate-like amyloid-beta sequence but no cerebral amyloidosis in aged tree shrews.

A central pathological feature of Alzheimer's disease is the profuse deposition of amyloid-beta protein (Abeta) in the brain parenchyma and vessel walls. Abeta also forms deposits in the brains of a variety of mammals, including all aged non-human primates studied to date. The sequence of Abeta in these animals is identical to that in humans. No Abeta deposits have been found in the brains of wild-type rats and mice, suggesting that the three amino acid differences between their Abeta and that of amyloid-bearing mammals impedes the fibrillogenicity of Abeta. Analysis of the primary sequence of the beta-amyloid precursor protein in tree shrews revealed a 98% similarity and 97% identity with the human protein. Furthermore, the predicted amino acid sequence of Abeta in tree shrews is identical to that in humans. However, immunohistochemical analysis failed to reveal beta-amyloid deposits in the neural parenchyma or vasculature of eight aged (7-8 years) tree shrews (Tupaia belangeri). The lack of correlation between the Abeta sequence and amyloid formation suggests that other factors contribute to cerebral amyloid deposition in aged animals.

Quantitative autoradiography of [3H]norharman [( 3H]beta-carboline) binding sites in the rat brain.

The anatomical distribution of [3H]norharman binding sites was determined by quantitative autoradiography in rat brain slices. They are enriched in hypothalamic, thalamic, accumbens and amygdaloid nuclei as well as in hippocampal, neocortical and olfactory-related structures. The distribution pattern differs from that of other previously described receptors or binding sites (e.g. monoamine oxidase, benzodiazepine, tryptamine, 5-hydroxytryptamine receptors (5-HT1A, 5-HT1B, 5-HT1C, 5HT2], which suggests that a unique class of [3H]norharman binding sites exists in the rat brain. The findings are consistent with previous experiments which showed high affinity binding sites for [3H]norharman in rat brain membranes (KD 1.552 nM; autoradiography KD 5.5 nM). A correspondence in the displacing activity of drugs was found for both methods (crude membrane fraction: harman much greater than tryptamine much greater than 5-hydroxytryptamine greater than N-methyl-beta-carboline-3-carboxamide (FG 7142) = diazepam; autoradiography: harman much greater than tryptamine much greater than FG 7142 greater than 5-hydroxytryptamine greater than diazepam). Provided that the binding sites represent functional receptors, the present anatomical findings may explain the biological effects of norharman, e. g. pro-conflict behaviour (limbic-hypothalamic structures), tonic-clonic convulsions (limbic-cortical structures) and alterations of locomotor activity (accumbens nucleus).

Expression of cyclooxygenase (COX)-1 and COX-2 in adaptive cytoprotection induced by mild stress.

Prostaglandins (PG) derived from COX-1 play an important role in the maintenance of mucosal integrity but the role of COX-2-derived products in mucosal defence mechanism has not been fully explained. Mild stress is known to prevent gastric mucosal lesions induced by severe stress via the phenomenon of adaptive cytoprotection but it remains unknown which COX is involved in this adaptation. In this study, the mucosal expression of COX-1 and COX-2 was examined and the inhibitors of these enzymes were used to determine the contribution of these enzymes in adaptive cytoprotection induced by mild stress. Male Wistar rats were exposed to mild water immersion and restraint stress (WRS) at various time intervals ranging from 5 min up to 2 h followed 1 h later by exposure to severe 3.5 h WRS with or without pretreatment with: 1) NS-398 (10 mg x kg(-1) i.g.), a selective COX-2 inhibitor; 2) resveratrol (5 mg x kg(-1) i.g.), a selective COX-1 inhibitor; 3) meloxicam (2 mg x kg(-1) i.g.), preferential COX-2 inhibitor; and 4) indomethacin (5 mg x kg(-1) i.p), non-selective inhibitor of COX. The number of WRS lesions was counted, gastric blood flow (GBF) was measured by H2-gas clearance technique, mucosal biopsy samples were taken for the assessment of PGE2 by radioimmunoassay, and the expression of COX-1 and COX-2 mRNA by RT-PCR. WRS for 3.5 h produced numerous gastric lesions, decreased GBF by 48% and inhibited formation of PGE2 by 68% as compared to intact mucosa. Exposure to mild WRS during 5-30 min by itself failed to affect mucosal integrity but significantly attenuated gastric lesions induced by exposure to severe 3.5 h stress; the maximal protective effect being achieved with mild WRS during 15 min. This protective effect was accompanied by the rise in GBF and the generation of PGE2 in the gastric mucosa. After extension of mild WRS from 15 min up to 1 or 2 h before more severe 3.5 h WRS, the loss of cytoprotective effect of mild WRS against severe stress accompanied by significant fall in the GBF were observed. Pretreatment with NS-398 (10 mg x kg(-1) i.g.) that failed to affect mucosal PGE2 generation, reduced significantly the protection and accompanying rise in GBF produced by mild WRS whereas resveratrol partly reduced the protection and the rise in GBF induced by mild WRS. Meloxicam or indomethacin significantly inhibited PGE2 generation and completely abolished the hyperemia and protection induced by mild WRS against more severe stress. The protective and hyperemic effects of mild WRS were completely restored by the addition of 16,16 dm PGE2 (5 microg x kg(-1) i.g.) to NS-398 or resveratrol, while the deleterious effects of meloxicam and indomethacin were significantly attenuated by the concomitant treatment with this PGE2 analogue. We conclude that PG derived from both, COX-1 and COX-2 appear to be involved in adaptive cytoprotection developed in response to mild stressors.

Involvement of gastrin in gastric secretory and protective actions of N-alpha-methyl histamine.

N alpha-methylhistamine (N alpha-MH) is one of an unusual metabolite of histamine that was found in Helicobacter pylori-infected stomachs and is believed to interact with specific histamine H(1), H(2) and H(3)-receptors to stimulate gastric acid secretion and gastrin release from isolated G-cells but the effects of N alpha-MH on gastric mucosal integrity have been little studied. This study was designed; (1) to compare the effect of exogenous N alpha-MH with that of standard histamine on gastric secretion and plasma gastrin levels in rats equipped with gastric fistula (series A); and (2) to assess the action of N alpha-MH on gastric lesions induced by 100% ethanol (series B) in rats with or without removal of antral portion of the stomach (antrectomy). Rats of series B were pretreated intragastrically (i.g.) or intraperitoneally (i.p.) with N alpha-MH or histamine (0.1-2 mg/kg) 30 min prior to 100% ethanol (1.5 ml, i.g.) with or without: (1) vehicle (saline); (2) RPR 102681 (30 mg/kg i.p.), to block CCK-B/gastrin receptors; and (3) ranitidine (40 mg/kg s.c.) to inhibit histamine H(2)-receptors. The area of gastric lesions was determined planimetrically, gastric blood flow (GBF) was assessed by H(2)-gas clearance method and venous blood was collected for determination of plasma gastrin levels by radioimmunoassay (RIA). N alpha-MH and histamine dose-dependently increased gastric acid output (series A); the dose increasing this secretion by 50% (ED(50)) being 2 and 5 mg/kg i.g or i.p., respectively, and this effect was accompanied by a significant rise in plasma gastrin levels. Both, N alpha-MH and histamine attenuated dose-dependently the area of gastric lesions induced by 100% ethanol (series B) while producing significant rise in the GBF and plasma immunoreactive gastrin increments. These secretory, protective, hipergastrinemic and hyperemic effects of N alpha-MH and histamine were completely abolished by antrectomy, whereas pretreatment with RPR 102681 attenuated significantly the N alpha-MH and histamine-induced protection against ethanol damage and accompanying hyperemia. Ranitidine, that produced achlorhydria and a further increase in plasma gastrin levels, failed to influence the N alpha-MH- and histamine-induced protection and accompanying rise in the GBF. We conclude that (1) N alpha-MH stimulates gastric acid secretion and exhibit gastroprotective activity against acid-independent noxious agents in the manner similar to that afforded by histamine; and (2) this protection involves an enhancement in the gastric microcirculation and release of gastrin acting via specific CCK-B/gastrin receptors but unexpectedly, appears to be unrelated to histamine H(2)-receptors.