Vagally mediated effects of brain stem dopamine on gastric tone and phasic contractions of the rat.

Dopamine (DA)-containing fibers and neurons are embedded within the brain stem dorsal vagal complex (DVC); we have shown previously that DA modulates the membrane properties of neurons of the dorsal motor nucleus of the vagus (DMV) via DA1 and DA2 receptors. The vagally dependent modulation of gastric tone and phasic contractions, i.e., motility, by DA, however, has not been characterized. With the use of microinjections of DA in the DVC while recording gastric tone and motility, the aims of the present study were 1) assess the gastric effects of brain stem DA application, 2) identify the DA receptor subtype, and, 3) identify the postganglionic pathway(s) activated. Dopamine microinjection in the DVC decreased gastric tone and motility in both corpus and antrum in 29 of 34 rats, and the effects were abolished by ipsilateral vagotomy and fourth ventricular treatment with the selective DA2 receptor antagonist L741,626 but not by application of the selective DA1 receptor antagonist SCH 23390. Systemic administration of the cholinergic antagonist atropine attenuated the inhibition of corpus and antrum tone in response to DA microinjection in the DVC. Conversely, systemic administration of the nitric oxide synthase inhibitor nitro-l-arginine methyl ester did not alter the DA-induced decrease in gastric tone and motility. Our data provide evidence of a dopaminergic modulation of a brain stem vagal neurocircuit that controls gastric tone and motility.NEW & NOTEWORTHY Dopamine administration in the brain stem decreases gastric tone and phasic contractions. The gastric effects of dopamine are mediated via dopamine 2 receptors on neurons of the dorsal motor nucleus of the vagus. The inhibitory effects of dopamine are mediated via inhibition of the postganglionic cholinergic pathway.

High-intensity exercise training induces morphological and biochemical changes in skeletal muscles.

IN THE PRESENT STUDY WE INVESTIGATED THE EFFECT OF TWO DIFFERENT EXERCISE PROTOCOLS ON FIBRE COMPOSITION AND METABOLISM OF TWO SPECIFIC MUSCLES OF MICE: the quadriceps and the gastrocnemius. Mice were run daily on a motorized treadmill, at a velocity corresponding to 60% or 90% of the maximal running velocity. Blood lactate and body weight were measured during exercise training. We found that at the end of training the body weight significantly increased in high-intensity exercise mice compared to the control group (P=0.0268), whereas it decreased in low-intensity exercise mice compared to controls (P=0.30). In contrast, the food intake was greater in both trained mice compared to controls (P < 0.0001 and P < 0.0001 for low-intensity and high-intensity exercise mice, respectively). These effects were accompanied by a progressive reduction in blood lactate levels at the end of training in both the exercised mice compared with controls (P=0.03 and P < 0.0001 for low-intensity and high-intensity exercise mice, respectively); in particular, blood lactate levels after high-intensity exercise were significantly lower than those measured in low-intensity exercise mice (P=0.0044). Immunoblotting analysis demonstrated that high-intensity exercise training produced a significant increase in the expression of mitochondrial enzymes contained within gastrocnemius and quadriceps muscles. These changes were associated with an increase in the amount of slow fibres in both these muscles of high-intensity exercise mice, as revealed by the counts of slow fibres stained with specific antibodies (P < 0.0001 for the gastrocnemius; P=0.0002 for the quadriceps). Our results demonstrate that high-intensity exercise, in addition to metabolic changes consisting of a decrease in blood lactate and body weight, induces an increase in the mitochondrial enzymes and slow fibres in different skeletal muscles of mice, which indicates an exercise-induced increase in the aerobic metabolism.

Radiofrequency-assisted right hemihepatectomy by using a new incremental bipolar generator combined with liver hanging maneuver.

In order to reduce bleeding, various surgical maneuvers and devices have been used and radiofrequency (RF)-assisted liver resections have been recently advocated by many authors. We performed a right hemihepatectomy for colorectal liver metastases by using new radiofrequency generator (Surtron SB®) combined with hanging maneuver to facilitate the application of the probe and avoid injuries of the interior vena cava (IVC). Operative time was 245 minutes, intraoperative blood loss was 120 ml, transection blood loss was 70 mL. No blood units were administered at any time. After a regular postoperative (PO) course patient was discharged on 11th PO day with normal liver function tests. In conclusion combined use of a RF generator and hanging maneuver in right hemihepatectomy provide bloodless parenchymal transection. The enhanced exposure contributes to better hemostasis and permits the best allocation of the comb with protection of the IVC from injuries.

Towards tolerance in liver transplantation.

Life-long immunosuppression has always been considered the key in managing liver graft protection from recipient rejection. However, it is associated with severe adverse effects that lead to increased morbidity and mortality, including infections, cardiovascular diseases, kidney failure, metabolic disorders and de novo malignancies. This explains the great interest that has developed in the concept of tolerance in recent years. The liver, thanks to its marked tolerogenicity, is to be considered a privileged organ: up to 60% of selected patients undergoing liver transplantation could safely withdraw immunosuppression.

Ab initio Everolimus-based Versus Standard Calcineurin Inhibitor Immunosuppression Regimen in Liver Transplant Recipients.

AIM: We designed a retrospective case-control study to determine the efficacy and feasibility of everolimus (EVR) combined with low-dose tacrolimus (Tac) ab initio versus standard-dose Tac after liver transplantation (LT). METHODS: Seventy-one adult LT patients, receiving EVR and low-dose Tac without corticosteroids or induction therapy from postoperative day 1 (EVR group) were compared with a well-matched control group of 61 recipients treated with standard-dose Tac in association with antimetabolite. RESULTS: Baseline characteristics for the two groups were comparable. The overall patient and graft survival rates were similar (P = .908). Liver function was stable during the follow-up. In the EVR group, biopsy-proven acute rejection occurred in two cases (2.8%), whereas chronic rejection occurred in one (1.4%). The EVR group experienced a better renal function already after 2 weeks (estimated glomerular filtration rate: 89.85 [36.46 to 115.3] mL/min/1.73 m2 vs. 68.77 [16.11 to 115.42] mL/min/1.73 m2; P = .013), which was also observed after a median time of 27 months (range, 0 to 82 months) from LT (estimated glomerular filtration rate: 80 [45 to 118.3] mL/min/1.73 m2 vs. 70.9 [45 to 88.4] mL/min/1.73 m2; P = .04). After a median time of 27 months, the EVR group showed lower incidence of arterial hypertension and insulin-dependent diabetes mellitus. CONCLUSION: Ab initio EVR-based immunosuppression could be a valid option immediately after surgery in recipients at high-risk for post-LT renal impairment.

Use of mycophenolate mofetil in liver transplantation: a literature review.

Mycophenolate mofetil (MMF) is an immunosuppressive drug, exhibiting its effect through inhibition of proliferation of T and B lymphocytes. Standard primary immunosuppressive therapy after orthotopic liver transplantation (OLT) is based on a calcineurin-inhibitor (CNI): cyclosporine or tacrolimus. Renal failure with arterial hypertension, due to CNI side-effects, is a major cause of morbidity and mortality after OLT. Several studies have shown the efficacy of MMF to improve CNI-induced nephrotoxicity, blood pressure, and uric acid concentration in liver transplant patients with concomitant reduction or withdrawal of CNI. Predose plasma mycophenolic acid concentrations (MPA) are related to adverse events, drug dose, and clinical status. Blood level values outside the suggested MPA therapeutic range are associated with acute rejection episodes and side effects, which have been described in about half of the patients treated with MMF. Most authors have described gastrointestinal and hematological side-effects, whereas these appear usually dose related, responding quickly to reduction. MMF is potent and safe immunosuppressive agent, and replacement of CNI by MMF in liver transplant patients with renal dysfunction may improve not only kidney function but also other CNI-associated side-effects, such as hypertension and hyperuricemia, with a low risk of rejection.

Interposition of the right colic angle between the liver and thoracic wall: an unusual cause of massive rectal bleeding following percutaneous biopsy in a liver transplant recipient.

A 37-year-old male liver transplant recipient developed hemorrhagic shock from massive rectal bleeding a few hours after a protocol liver biopsy. Conservative treatment was not possible and the patient underwent a radiological investigation of the celiac and mesenteric arterial trunks, which showed active bleeding from a branch of the middle colic artery. Embolization with Tabotamp (Ethicon, Neuchatel, CH Switzerland) particles led to successful hemostasis. We thus discuss the possible mechanisms of injury. To our knowledge, no other cases of major rectal bleeding following percutaneous liver biopsy have been reported in the literature. We emphasize the need for Doppler ultrasound assistance, in terms of either preoperative examination with or without marking or guidance. The latter is the safest and most reliable technique, given the low risk of puncture of other organs and the low probability of obtaining an inadequate sample.

Differential attachment by conidia of the endophyte, Discula umbrinella (Berk. & Br.) Morelet, to host and non-host surfaces.

Differential attachment of conidia to leaves of different species (host and non-host) has been observed in the endophytic fungus, Discula umbrinella (Berk. & Br.) Morelet, a deuteromycete known to cause occasional epidemics of anthracnose in beech stands. On beech leaves, attachment gradually increased over 24 h and reached a maximum after 16-24 h; there were small differences in attachment between conidia suspended in water and those in HEPES buffer. The range of variation of results obtained with conidia suspended in HEPES was smaller but the adhesion was clearly enhanced. The adhesion of conidia to the host surface was highest at pH 5, and decreased with increasing pH. Heat and chemical treatments significantly reduced attachment. Two factors (or groups of factors) are likely to be involved in the recognition process. The first is heat-labile, the second one could be a non-protein molecule present on the conidial surface and actively recognized by the host. The physiological similarity between endophytes and other symbionts is briefly discussed.

A rapid tissue culture assay for the detection of okadaic acid and related compounds in mussels.

Okadaic acid, the main toxin of the diarrhoetic shellfish poisoning (DSP) group, shows high cytotoxicity to Buffalo green monkey (BGM) kidney cell cultures after different times according to concentration. A rapid method of detecting the presence of okadaic acid and related compounds in contaminated mussels by means of a cytotoxicity test is presented. The method is based on direct microscopic observation of toxin-induced morphological changes in BGM cell cultures. A high correlation (r = 0.950; P < 0.001) was found between the official mouse bioassay and the cytotoxicity test conducted on naturally contaminated samples of Mytilus galloprovincialis.

Influence of the extraction procedure on recovery of okadaic acid from experimentally contaminated mussels.

Hepatopancreas samples from mussels (Mytilus galloprovincialis) experimentally contaminated with okadaic acid were analysed with Yasumoto's mouse bioassay and HPLC. A likely effect of some components of the hepatopancreas on the results (matrix effect) was evaluated, and a possible loss of toxin during the extraction phase was quantified. Experiments were conducted by comparing two different extraction procedures. Under our experimental conditions, the results obtained from mouse bioassay showed no matrix effect with either procedure. A certain quantity of the actual amount of okadaic acid contained in the sample was found to be lost after the extraction, i.e. 10.2-17.0% in samples extracted with acetone alone and 9.8-18.5% in samples extracted with acetone and ether.

Diarrhetic shellfish poison in mussels: comparison of methods of detection and determination of the effectiveness of depuration.

The lack of specificity of the Yasumoto mouse bioassay for Diarrhetic Shellfish Poisoning (DSP) toxin and the possibility of obtaining false positive results, prompted a search for a suitable method to confirm doubtful results. The mouse bioassay, an enzyme-linked immunoassay (ELISA) and a tissue culture bioassay were compared; in addition the efficiency of depuration of toxic mussels in ozonized water was evaluated. DSP assay using tissue cultures was found suitable for confirming results obtained using the mouse bioassay, particularly where interpretation was difficult. The ELISA kit gave satisfactory results, but it responded only to okadaic acid and dinophysistoxin 1. Depuration reduced toxicity in some cases after 3 days of treatment.

Depuration of Mytilus galloprovincialis experimentally contaminated with hepatitis A virus.

Mussels (Mytilus galloprovincialis) were contaminated with known amounts of laboratory strains of hepatitis A virus and Poliovirus 1 and the effectiveness of a self-cleansing mechanism was studied using a pilot depuration system. Both viruses were rapidly bioaccumulated by mussels and the maximal concentration of about 10(4) TCID50/ml was reached within 1.5 hours. Depuration was carried out up to 24 h; infectivity titer decreased to 10(2) TCID50/ml and 10(3.2) TCID50/ml within 6 h in hepatitis A virus and Poliovirus 1 contaminated mussels, respectively, but only a very slight further decrease was obtained after 24 h. E. coli was used as a control; within 24 h the concentration decreased from 40 to 2 bacteria/ml of mussel (MPN). The elimination of bacteria is not a reliable parameter to control the effectiveness of viral depuration.

Detection of hepatitis A virus in shellfish by nested reverse transcription-PCR.

A method for the detection of HAV in shellfish, based on the use of guanidinium isothiocyanate-containing solution for RNA extraction and purification steps, followed by nested PCR, is hereby proposed. Tests were carried out on mollusc samples spiked with HAV strain FG. Results showed that in samples subjected only to one round of PCR it was possible to detect HAV at concentrations of 10(3)-10(4) TCID50/10 g of mollusc. The use of the nested PCR renders the system more sensitive and specific enabling the identification of HAV concentrations as low as 1 TCID50/10 g of mollusc. Furthermore thus method, in addition to allowing the avoidance of confirming tests, such as hybridization, proved to be inexpensive and simple to perform.

Behavior of aeromonas hydrophila in bottled mineral waters.

The growth and survival of Aeromonas hydrophila in three types of natural mineral waters were investigated. Mineral waters with different levels of mineral content (low, medium, and high) were experimentally contaminated with A. hydrophila, stored at different temperatures (10 degrees C and 20 degrees C), and analyzed at intervals over a 60-day period. Water samples that were not experimentally contaminated were investigated for indigenous A. hydrophila. The results confirmed that A. hydrophila may occur naturally in mineral waters and showed that the level of mineral content, temperature, length of storage, and, in some cases, the type of container used may favor the growth of A. hydrophila. The greatest proliferation was observed in water with a low mineral content stored in PET bottles at 10 degrees C, in which A. hydrophila peaked at day 28 (4.47 +/- 0.01 log CFU/100 ml). At 20 degrees C, the same load was observed at day 60. The presence of high densities of A. hydrophila in bottled mineral water can constitute a risk for some groups of consumers, such as elderly and immunocompromised persons.

Liver transplantation in the presence of portal vein thrombosis: report from a single center.

Portal vein thrombosis (PVT) is a frequent finding in liver transplantation, the management of which depends mainly on its extent. In cases of mild to moderate PVT, a low dissection of the portal trunk, a jump graft, or direct implantation of graft portal vein into large venous collaterals or thrombectomy offer alternatives. For severe PVT anecdotal reports suggest that cavoportal hemitransposition, portal arterialization, or combined liver and intestine transplantation may be attempted, although the results to date are not satisfactory. When extensive perivenous and venous inflammatory changes reach the infrapancreatic region, liver transplantation probably should not be performed due to the high mortality rate.

Marginal donors in liver transplantation.

Marginal liver donor criteria included the following: obesity (weight >100 Kg or BMI >27), age >50 years; macrovesicular steatosis >50%; intensive care unit stay >4 days; prolonged hypotensive episodes of >1 hour, and <60 mm Hg with high inotropic drug use (dopamine, [DPM] > 14 microg/kg per minute); cold ischemia time >14 hours, peak serum sodium >155 mEq/L; sepsis, viral infections, and alcoholism; high levels of bilirubin, ALT, and AST, or extrahepatic neoplasia. Between August 1992 and May 2003, we performed 251 liver transplants in 241 patients of whom 155 are presently alive. We used 124 (49.4%) standard donors and 127 (50.6%) marginal donors. Among the group that received a standard donor, 81 (65.3%) are still alive. Among recipients of organs from marginal donors. 81 (63.8%) are still alive. We also assessed the quality of donors according to the severity of recipient disease. For standard donors these outcomes were 61.5% for UNOS 1, 37.5% for UNOS 2A, 73.2% for UNOS 2B, and 80% for UNOS 3 for marginal donors they were 46.1% for UNOS 1, 53.6% for UNOS 2A, 70.7% for UNOS 2B, and 63.6% for UNOS 3. Among the patients who received a liver from a donor >60 years old, there were no survivors in UNOS 1 and 2A, but there were good results in groups 2B and 3. These results suggest there is no difference between marginal and standard donors, even in sick patients, with the exception of donor age.

[Comparative studies on the course of microbial flora in natural mineral waters bottled in glass, PVC and laminated polyethylene]. / Osservazioni comparative sull'andamento della flora microbica delle acque minerali naturali confezionate in vetro, "PVC" e "tetrabrik"

The Authors report the results of comparative investigations carried out on some mineral waters bottled in various containers (laminated polyethylene, glass, PVC). The microbic charges vary in relation to the kind of container and resulted to be lower in the case of containers made of polyethylene.

[Determination of bacteria count by enumeration of microcolonies with an electronic counter apparatus (author's transl)]. / Determinazione della carica microbica mediante numerazione delle microcolonie eseguita al contatore elettronico di particelle

In this paper a method is described to determine the bacteria count of samples by enumerating the microcolonies with the aid of a "Coulter Counter" automatic apparatus. Samples of bacterial cultures were incubated in a suitable medium at 32 degrees C for 12 h, then passed through a Coulter Counter aperture of 200 mu diameter to count the microcolonies. Microcolonies from cultures grown in similar conditions were also enumerated by the classical plate method. Comparison showed a good correction between the two sets of results after logarithmic transformation. Some advantages and limitations of this automatic technique are discussed, in view of its routine employment in food analysis.

Deep vein thrombosis as debut of cytomegalovirus infection associated with type II cryoglobulinemia, with antierythrocyte specificity in a kidney transplant recipient: a case report.

Immunologic alterations, such as cryoglobulinemia, have been described in the acute phase of primary cytomegalovirus (CMV) infections in immunocompetent patients. There are few references about these influences of a primary CMV infection in an at-risk kidney transplant recipient (donor positive/recipient negative-D(+)/R(-)). Herein we have described the case of a 46-year-old man, who was naive for CMV and underwent renal transplantation from a CMV+ cadaveric donor, thereby at high risk for disease transmission. The immunosuppression consisted of basiliximab, tacrolimus, mycophenolate mofetil, and steroids. The recipient was not treated with CMV prophylaxis, but rather regularly screened for possible pre-emptive treatment. At 35 days after transplantation, he was admitted because of deep vein thrombosis (DVT) in the transplant ipsilateral lower limb accompanied by oliguria, fever, and epigastric pain accompanied by type II cryoglobulinemia and acute CMV infection. The direct antiglobulin test (DAT) for C3d was positive. The cryoglobulins displayed anti-red blood cell specificity, with maximum activity at 4°C. The DVT was successfully treated with locoregional thrombolysis in combination with anticoagulant therapy. The DAT improved with CMV treatment and increased steroid therapy. The urine output and renal function tests improved with resolution of the thrombosis, achieving complete recovery without sequelae. Our hypothesis was that CMV infection triggered cryoglobulinemia. The blood disorder caused hyperviscosity, inducing DVT. This case, of CMV infection showed associated cryoglobulinemia presenting with antierythrocyte specificity in a kidney transplant recipient.

High-intensity exercise training produces morphological and biochemical changes in adrenal gland of mice.

The effects of training are dependent on complex, adaptive changes which are induced by acute physical exercise at different levels. In particular, evidence shows that the hypothalamus-pituitary-adrenocortical axis, as well as the sympatho-adrenomedullary system, is mainly involved in mediating the physiological effects of physical exercise. The aim of the present study was to investigate, through a morphological and biochemical approach, the effects of training on the adrenal gland of mice, following two different protocols consisting of either low- or high-intensity training. Mice were run daily on a motorised treadmill for 8 weeks, at a velocity corresponding to 60% (low-intensity exercise) or 90% (high-intensity exercise) of the maximal running velocity previously determined by an incremental exercise test. We found that physical exercise produced an increase in the adrenal gland size compared with the control (sedentary) mice. The increase was 31.04% for mice that underwent high-intensity exercise and 10.08% for mice that underwent low intensity exercise, and this appeared to be the result of an increase in the area of both the adrenal cortex and adrenal medulla. Morphological analysis of the adrenal cortex showed that both types of exercise produced an increase in cytoplasmic vacuoles in steroidogenic cells, appearing more abundant after high-intensity exercise. No change was found in the reticulate zone. In the adrenal medulla, despite the absence of morphological changes, immunohistochemistry for tyrosine hydroxylase, dopamine ß-hydroxylase and phenyl-ethanolamine-N-methyltransferase demonstrated an increased immunopositivity for these cathecolamine-synthesizing enzymes after intense exercise. These results were confirmed by immunoblot accompanied by densitometric analysis.