5 and 3. Mutations in PTEN In patient JUV�\16, the MLPA test revealed an isolated ��deletion�� of PTEN exon 7. Sequencing this exon, we found http://www.selleckchem.com/products/baricitinib-ly3009104.html the heterozygous nonsense mutation c.697C��T;p.Arg233X localised close to the hybridisation site of the MLPA probe for PTEN exon 7. The mutation was also found in the affected father of the index patient. Subsequently, all the remaining mutation�\negative patients were screened for PTEN germline mutations by direct sequencing. Of the 40 patients, 1 (JUV�\18) was found to have a pathogenic splice site mutation in intron 4 (c.253+1G��T). Genotype�Cphenotype correlation The colorectal phenotype of SMAD4 and BMPR1A mutation carriers was indistinguishable: There was no significant difference in the median age at diagnosis of JPS between carriers of the SMAD4 (12 years) and the BMPR1A (14 years) mutations (p=0.

48; table 33).). Both groups had a comparable number and histological spectrum of colorectal polyps. Table 3Genotype�Cphenotype correlation (age at diagnosis, gastric polyposis, hereditary haemorrhagic telangiectasia phenotype) in carriers of SMAD4 and BMPR1A mutations Gastric polyposis In a previous study on 29 unrelated patients with JPS with 12 identified mutations, we found an over�\representation of gastric polyposis among carriers of SMAD4 mutations compared with carriers of BMPR1A mutations.6 A similar trend was observed when only the 27 patients (22 families) with known status of gastric polyposis who had not been analysed in our previous study were considered: 11 of 17 patients with SMAD4 mutations, but none of 11 patients with BMPR1A mutations, had gastric polyposis (p<0.

01). In the combined sample (previously and newly analysed cases) information on results of gastroscopy was available for 30 patients with SMAD4 mutations (20 unrelated index patients and 10 affected relatives) and for 13 patients with BMPR1A mutations (nine index patients and four affected relatives) (table 33).). Of the 30 patients with a SMAD4 mutation, 22 (73%) were found to have gastric polyposis. In contrast, only 1 of the 13 patients (8%) with BMPR1A mutations had gastric polyps (p<0.001). The over�\representation of gastric polyposis in SMAD4 mutation carriers remained true even Drug_discovery when age at gastroscopy was considered. Although the median age at gastroscopy was 35 (range 11�C60) years for patients with SMAD4 mutations and 26 (range 4�C73) years for patients with BMPR1A mutations, the difference was not significant (p=0.71) (table 33). Generally, gastric polyposis in SMAD4 mutation carriers is diagnosed later in life (median age at diagnosis 41 years) compared with diagnosis of colorectal polyps (12 years) (p<0.001).

Accordingly, follow-up and deferring therapy has been suggested in this patient group. A recent review of three large randomized trials has shown that patients with NALT have significantly lower inflammation and fibrosis scores on liver biopsy than patients with elevated ALT [9]. Nevertheless, these patients can have progressive liver disease and develop advanced fibrosis or cirrhosis http://www.selleckchem.com/products/Imatinib-Mesylate.html [3,10]. These studies suggest that patients with chronic HCV with NALT should be evaluated similarly to patients with elevated ALT levels because they are at risk for developing significant liver disease [9]. Using periodic liver biopsies to determine if and when to use antiviral treatment is unlikely to elicit a favourable patient response and can lead to higher costs, increased cumulative cirrhosis incidence and decreased survival rates in comparison with ��empirically based�� treatments [11,12].

Although considered the gold standard for assessment of liver fibrosis, liver biopsies have limitations, including inter-observer variability, sampling error and risks for complications. Reliable and inexpensive noninvasive methods to assess disease progression are a necessity in this setting [12]. Breath testing is based on the principal that an ingested substrate is metabolized, and a measurable metabolite is then expelled by the respiratory system. An ideal compound for this purpose is metabolized solely by the liver and therefore reflects liver function. Breath testing has been used experimentally and clinically for several decades [10], including for follow-up on patients with chronic liver disorders.

The major drawbacks of these tests are the need for traditional, cumbersome isotopic ratio mass spectrometry methods, a prolonged testing time and patient inconvenience. The BreathID? continuous online 13C-methacetin breath test (MBT), which reflects hepatic microsomal function (CYP1A2), is a laser-based technology that creates an infrared emission precisely matching the absorption spectrum of CO2 and can detect variations of less than 1/1000 in the 13CO2/12CO2 ratio measurement. The system is based on the measurement of CO2 by molecular correlation spectroscopy. This test offers several advantages: It is an office-based, noninvasive tool for the assessment of both liver inflammation and fibrosis does not involve a blood test and can provide an immediate result at the point-of-care.

The aim of the present study was to determine its accuracy in assessing the degree of liver fibrosis and inflammation in patients with chronic HCV infection and NALT. Methods Study population Patients From 1 March 2006 to 31 May 2006, we enrolled 100 consecutive, unselected, patients with previously untreated, chronic HCV. Cilengitide All were anti-HCV and HCV RNA positive, with a normal serum ALT level (�ܡ�2 ULN) on two separate tests during the preceding 6 months.

Upon interaction of Lapatinib chemical structure Fas, a member of the TNF family, with its ligand, FasL, death is induced via caspase activation. Several mechanisms may render cells resistant to FasL-induced apoptosis. Bosentan sensitisation to FasL-mediated apoptosis in HT29 cells was completely blocked by the general caspase inhibitor zVAD-fmk, demonstrating the involvement of the caspase proteases. These results suggest that ET-1-receptor blockade allows HT-29 cells to undergo caspase activation, via the Fas pathway. However, ET-1 does not sensitise cells to death induced by TNF-��, another member of the TNF-death receptor family. In conclusion, we have shown that ET-1 is not a proliferation-inducing factor in human colon carcinoma. Blockade of ET receptors either induces apoptosis or sensitises cells to Fas-induced apoptosis.

In colon cancer cells, low concentrations of ET-1, either added exogenously or secreted by the tumour cells, are permissive for colon cancer cell survival, promoting resistance to FasL-mediated apoptosis, while high concentrations of either receptor antagonists or ET-1 promote apoptosis. Acknowledgments We thank Ms S Gros, P Fioroni and B Carnal for excellent technical assistance; Drs A Fontana for the kind gift of FasL-producing cells, J-D Aubert, FT Bosman, F Pinet, G Egidy and O Valdenaire for helpful discussions and suggestions, M Clozel and S Roux from Actelion (Basel) for providing bosentan and helpful comments. This work was supported by grant from the Swiss League and Research against Cancer (SKL 353-9-1996, KFS 947-09-1999 and KFS 1070-09- 2000), the Swiss National Foundation for Scientific Research (Grants 3200-045908.

95 and 3200-064907.01) and the Swiss Programme ��Cotutelle de th��se��.
Extracellular senile plaques and phosphorylated tau-associated intraneuronal neurofibrillary tangles (NFTs) are the two classical microscopic pathologies of Alzheimer��s disease (AD) [1]. Senile plaques comprise a dense core of amyloid-�� (A��) that is surrounded by dystrophic neurites [1]. A�� is a 39�C43 amino acid proteolytic product of a much larger amyloid precursor protein (APP). APP is an integral membrane protein processed by the proteases ��-secretase or ��-secretase to produce ��-C terminal fragment (CTF-��) or ��-C terminal fragment (CTF-��), respectively. These fragments are subsequently cleaved by ��-secretase to produce P3 or A�� respectively, and a cytoplasmic tail dubbed APP-intracellular domain (AICD) [1].

APP proteolysis also releases soluble forms of APP (sAPP�� and sAPP��), and these soluble APPs may also now be considered biomarkers for AD [2]. On the other hand, monomeric A�� (4.3 kDa molecular weight) self-assembles into oligomers. These oligomers eventually deposit as large Dacomitinib fibrils in extracellular space, which assemble as amyloid plaques [1], [3].

The HBEC mucosal surfaces were washed with 500 ��l PBS for 30 min prior to experimentation to remove Vandetanib mechanism accumulated endogenous SPLUNC1. SPLUNC1 recovery into the ASL was measured over time by lavaging with 200 ��l PBS at timed intervals after the initial wash/volume load. To detect SPLUNC1, 20% by volume of the lavage was transferred onto a nitrocellulose membrane using a slot-blot apparatus (GE Healthcare, Pittsburgh, PA, USA). The blot was processed as described above using an anti-hPLUNC primary antibody (R&D Systems, Minneapolis, MN, USA). Transepithelial potential difference (Vt) studies A single-barreled Vt-sensing electrode was positioned in the ASL by micromanipulator and used in conjunction with a macroelectrode in the serosal solution to measure Vt using a voltmeter (World Precision Instruments, Sarasota, FL, USA), as described previously (16).

Circular dichroism (CD) G22-A39 (100 ��M) was dissolved in a buffer containing 10 mM sodium phosphate (pH 7.4) in a 1 mm cuvette. Using a Chirascan-plus instrument (Applied Photophysics Ltd., Leatherhead, UK), 5 individual spectra from 185 to 280 nm were recorded at 25 �� 1.0��C and averaged. All measurements were corrected for buffer signal. Expression and purification of human SPLUNC1 The SPLUNC1-��19 construct was created by cloning amino acid residues 20�C256 out of the SPLUNC1 cDNA described above for entry into pMCSG7 for protein expression. BL21-CodonPlus competent cells (Agilent Technologies, Santa Clara, CA, USA) were transformed with the expression plasmid and cultured in the presence of antifoam (50 ��l), ampicillin (100 ��g/ml), and chloramphenicol (34 ��g/ml) in Luria broth medium with vigorous shaking at 37��C until an OD600 of 0.

6 was attained. Expression was induced with the addition of isopropyl-1-thio-d-galactopyranoside (IPTG). Bacteria were collected by centrifugation at 4500 g for 20 min at 4��C. Cell pellets were resuspended in buffer A (20 mM potassium phosphate, pH 7.4; 50 mM imidazole; 500 mM NaCl; and 0.02% NaAzide) along with lysozyme, DNase1, and protease inhibitor tablets. Cells were sonicated, and cell lysate was separated into soluble and insoluble fractions using high-speed centrifugation. The soluble fraction was filtered, then flowed over a Ni-NTA His-Trap gravity column and washed with buffer A. The bound protein was eluted with buffer B (20 mM potassium phosphate, pH 7.

4; 500 mM imidazole; 500 mM NaCl; and 0.02% NaAzide) and separated using an S200 gel filtration column on an ?KTAxpress (GE Healthcare). The histidine tag was removed with Tev protease, leaving amino acid residues serine, Anacetrapib asparagine, and alanine on the N terminus of the protein. Another round of nickel and HPLC purification removed the tag from the purified SPLUNC1-��19. We confirmed that SPLUNC1-��19 purified in this fashion inhibited ENaC HBECs (n=6).

Methods Binding and transactivation assays BET bromodomain inhibitor Binding vectors for His-tagged protein production were prepared by inserting the ligand-binding domain cDNA of human LXR�� (amino acids 205�C447) in pET28 (Novagen, Gibbstown, NJ, USA) and the ligand-binding domain cDNA of LXR�� (amino acids 216�C461) in pET24D. Proteins were expressed in Escherichia coli and purified on Ni+ columns. Binding assays using LXR�� and LXR�� protein were run by adding reagents to Wallac Isoplate 1450�C514. Briefly, each 96 plate well contained assay buffer (20 mM Tris pH 7.5, 80 mM NaCl, 2 mM dithiothreitol, 0.125% Chaps and 10% glycerol), 0.1 mg SPA beads (polylysine-coated yttrium silicate beads, RPNQ0010P, GE Healthcare, Piscataway, NJ, USA), LXR�� (0.5 ��g) or LXR�� (0.

25 ��g), 30 nM 3H-ligand (Tularik T0901317, specific activity of 473 Kbq nmol?1) and test compound in a 10-point dose-response dilution. The assay mixture was shaken gently for 2 h on a plate shaker after which the beads were allowed to settle for 1 hour before counting. Transactivation vectors were prepared by inserting the ligand-binding domain cDNA sequences of human or mouse LXR�� and LXR�� in frame with the yeast Gal4 transcription factor DNA binding domain and the nuclear localization signal from the T-antigen of polyoma virus in the eucaryotic expression vector pSG5 (Stratagene, La Jolla, CA, USA). The ligand-binding domain cDNA of human LXR�� and LXR�� was the same as mentioned previously. The mouse sequence corresponded to amino acids 203�C445 for LXR�� and amino acids 201�C446 for LXR��.

The vectors were co-transfected with a pGL3 luciferase reporter plasmid containing a minimal SV40 promoter (Promega, Madison, WI, USA) and five copies of the UAS Gal4 recognition site into U2/OS osteosarcoma cells. Ligands were added as 10-point dose-response curves and then luciferase activity was measured after 48 h. Macrophage RCT All animal care and experimental procedures were approved by the Institutional Animal Care and Use Committee of the Netherlands Organization for Applied Scientific Research (TNO) or by the Ethics Review Committee on Animal Experiments (Gothenburg region). The animals received food and water ad libitum. Body weight and food intake were monitored during the study. Macrophage RCT was determined essentially as described by Naik et al. (2006).

J774A1 macrophages (obtained from Deutsche Sammlung von Mikroorganismens and Zellkulturen, DSMZ, Braunschweig, Germany) were cultured in RPMI supplemented with 10% fetal bovine serum and radiolabelled with 5 ��Ci mL?1[3H]cholesterol (specific activity 40�C60 Ci/mmol, PerkinElmer, Waltham, MA, USA) together with 100 ��g mL?1 acetylated LDL (Intracel, Rockville, MD, USA) and 1% BSA Dacomitinib (Sigma, St Louis, MO, USA) for 48 h. The J774A1 cells were then washed with phosphate-buffered saline (PBS) and resuspended in medium. The viability was estimated to be ~75% using Trypan blue.

Recombinant proteins that present tumor antigens in woodchuck liver were not available; therefore, a combined cell lysate of neoplastic liver tissues from five chronic WHV carrier Imatinib Mesylate molecular weight woodchucks with HCC was used for cell stimulation. Prior to treatment with SFV-enhIL-12, T-cell responses to tumor antigens were essentially undetectable in chronic WHV carrier woodchucks with HCC, because SIs were below the assay cutoff value of ��3.1 (Fig. (Fig.3A).3A). Following treatment with SFV-enhIL-12, all woodchucks had increases in their T-cell response to tumor antigens, and in two, T-cell response became positive, with SIs of ��3.1. The T-cell response was transient, peaked around the time of maximum tumor remission, and declined thereafter (Fig. (Fig.22 and and3).3).

In contrast, none of the control woodchucks had comparable changes in the tumor antigen-specific T-cell response. Liver antigens (i.e., a combined cell lysate of nonneoplastic liver tissues from the same woodchucks described above) were used as a control stimulator, and T-cell responses against these antigens were not detected in any woodchuck, demonstrating the specificity of the antitumoral T-cell response following treatment with SFV-enhIL-12 (Fig. (Fig.3B3B). FIG. 3. Antitumoral T-cell responses of chronic WHV carrier woodchucks following intratumoral treatment with increasing doses of SFV-enhIL-12. (A) T-cell responses to tumor antigens (i.e., clear supernatant of a combined cell lysate of neoplastic liver tissues …

The results for antitumoral T-cell responses were extended by determining the mRNA expression of leukocyte surface markers and cytokines in PBMC cultures stimulated with tumor antigens (Table (Table2).2). Compared to the pretreatment expression, treatment with SFV-enhIL-12 resulted in increased expression (��2.1-fold above the mRNA expression in unstimulated PBMC cultures but below the assay cutoff value of ��3.1) or positive GSK-3 expression (��3.1) of CD3, CD4, and CD8 in all woodchucks analyzed at 6 weeks posttreatment. At this time point the expression of IFN-�� was positive in tumor antigen-stimulated PBMC cultures from all SFV-treated woodchucks analyzed. Elevated IFN-�� expression correlated with increases in the expression of TNF-��, IL-6, and woodchuck IL-12, and expression of these cytokines was positive in both woodchucks treated with the highest dose of SFV-enhIL-12. Expression of leukocyte surface markers and cytokines was transient, peaked around the time of maximum tumor remission, and declined thereafter (Fig. (Fig.22 and Table Table2).2).

A rabbit polyclonal antiserum specific for the nsp2 subunit of the SFV replicase was used as the primary antibody (6). Analysis selleck Nutlin-3a of SFV-LacZ infectivity and ��-galactosidase expression in vitro. BHK-21 or HCC-derived cell lines were infected in duplicate plates with serial dilutions of the same SFV-LacZ virus stock. Twenty-four hours later, cells from one dish were lysed and the amount of ��-galactosidase protein present in the lysate was measured as described previously (23). Cells from the duplicate dish were stained with 5-bromo-4-chloro-3-indolyl-��-d-galactopyranoside (X-Gal) (Invitrogen), and the number of cells infected with SFV-LacZ was determined. The amount of ��-galactosidase protein produced per cell was calculated for each virus dilution by dividing the amount of ��-galactosidase protein detected per dish by the number of SFV-LacZ-infected cells in each dish.

Analysis of luciferase and IL-12 expression in vivo. Four woodchucks with HCC were used to determine that the expression of luciferase and IL-12 in hepatic tumors is dependent on the SFV dose and to verify that intratumoral IL-12 expression mediates increases in the levels of type I and II IFNs. Animals were anesthetized by intramuscular injection of ketamine (50 mg/kg) and xylazine (5 mg/kg). A blood sample was obtained, followed by laparotomy to expose the liver. Vector SFV-Luc or SFV-enhIL-12, each in a total volume of 0.6 ml, was administered intratumorally into one hepatic tumor at 10 separate sites. The first woodchuck received 1 �� 109 vp of SFV-Luc, whereas the second woodchuck was administered a threefold-higher dose of SFV-Luc (i.

e., 3 �� 109 vp). The latter woodchuck also received 3 �� 109 vp of SFV-enhIL-12 into another hepatic tumor. The third woodchuck was administered a fourfold-higher dose of SFV-enhIL-12 (i.e., 1.2 �� 1010 vp). The fourth woodchuck was left untreated, and the hepatic tumor from this animal served as a control. Twenty-four hours later, woodchucks were euthanized, a blood sample was obtained, and tissues (hepatic tumors, adjacent liver tissues, and other organs) were excised and snap-frozen in liquid nitrogen. Following homogenization in lysis buffer (phosphate-buffered saline containing 0.05% [vol/vol] Tween20 and protease inhibitor cocktail tablets [Complete; Roche, Basel, Switzerland]), samples were centrifuged twice for 10 min at 9,300 �� Entinostat g. Luciferase activity in the supernatants was determined using a conventional luminometer. IL-12 concentrations were determined in supernatants and in serum using a mouse p70-specific enzyme-linked immunosorbent assay kit (BD Bioscience, Franklin Lakes, NJ). The amount of total protein present in tissue homogenates was quantified using a standard Bradford assay.

Health Measures at T5 Two measures related to health at T5 were used. First, the number of different diseases or symptoms of diseases the participants had in the last fifteen years were reported. These diseases or symptoms consisted of diabetes, Nilotinib chronic obstructive pulmonary disease, hypertension, heart disease or any other vascular problems, heart attack, stroke, coughing up phlegm or blood, asthma, chronic bronchitis, emphysema or chronic lung disease, trouble remembering things, difficulty thinking or concentrating, trouble learning new things, trouble sleeping, and osteoporosis. An indicator variable was created and assigned the value of one when the participant reported five or more diseases or symptoms of diseases and was assigned the value of zero otherwise.

Second, the participants reported their general health condition, which is a one item scale scored with six options: very poor (1), poor (2), fair (3), good (4), very good (5), and excellent (6). An indicator variable was created with the value of one for poor or very poor general health and the value of zero otherwise. Analysis We used the Mplus software (Muth��n & Muth��n, 2010) to identify the joint developmental trajectories of cigarette smoking and perceived self-control (N = 479). We treated the trajectory variables (i.e., cigarette smoking and self control at each point in time) as censored normal variables. The full-information maximum likelihood approach (Schafer & Graham, 2002) was used to treat missing data. We set each trajectory polynomial to be quadratic.

We used 400 random sets of starting values to assure finding the maximum of the likelihood function. We used the minimum Bayesian information criterion (BIC) to determine the number Cilengitide of trajectory groups (T). For presentation purpose, we assigned each participant to the trajectory group with the largest Bayesian posterior probability (BPP). The observed trajectories for a group were the averages of cigarette smoking and self-control at each point in time for the participants assigned to the group (see Figure 1). Figure 1. Joint trajectories of smoking and perceived self-control: Group HL (chronic cigarette smoking and low perceived self-control); Group LL (infrequent or non-cigarette smoking and low perceived self-control); Group MM (chronic moderate cigarette smoking … We conducted partial correlation analyses to examine the associations between cigarette smoking (mean score of smoking T2�CT4) and reporting five or more diseases or symptoms (T5) and poor or very poor health rating (T5), partialling out the history of perceived self-control (T2�CT4).

The methods of this study were Lenalidomide CAS designed to minimize this risk (e.g., alternating smoking and non�Csmoking clips; presenting a media literacy intervention) and in doing so provided new methodological information for the field. There are limitations to this study. First, desire to smoke was the main dependent variable, not actual smoking behavior. Second, the sample of movie clips was selective. Therefore, these results may not generalize to other instances of movie smoking. Third, the study employed a reactively recruited sample of early adolescent never-smokers; our findings may not generalize to other populations of adolescents. Despite these limitations, the results of this study suggest that how smoking is portrayed in movies is important for understanding the influence of such portrayals on adolescent smoking.

Future research using randomized experimental designs and prospective designs would further advance knowledge in this domain of inquiry. Funding This research was supported by R01 “type”:”entrez-nucleotide”,”attrs”:”text”:”DA022496″,”term_id”:”78445730″,”term_text”:”DA022496″DA022496. Declaration of Interests None declared. Acknowledgments Special thanks are due to Rachel Burns, Jill Schaeffer, Sarah Frith, Preethi Saama, and Michelle Horner for their invaluable assistance in executing the procedures of this research.
The Internet is used extensively to market and sell tobacco (Freeman & Chapman, 2008; Malone & Bero, 2000). While cigarette advertising is regulated in traditional mainstream media, such as television and radio, sites such as YouTube, with their consumer-generated media content, remain largely unregulated (Ciolli, 2007).

Children access these types of sites and make up a large part of total users (Quantcast audience profile, 2009). Freeman and Chapman (2007) surveyed YouTube tobacco content in 2007 and found that smoking imagery was prolific and accessible. However, no previous studies have explored whether this content changes rapidly or stays relatively stable across time. This study builds on earlier work by examining the overall message and genre of YouTube videos related to cigarette smoking retrieved across two time periods. Importance of smoking imagery in smoking behavior Smoking rates among teens remain unacceptably high. In 2007, 20% of high school students in the United States were current cigarette smokers (Centers for AV-951 Disease Control [CDC], 2009). Each day in the United States, approximately 3,600 young people between the ages of 12 and 17 years try cigarette smoking and an estimated 1,100 become daily smokers (CDC). Approximately 90% of adult smokers began smoking before the age of 18 years (Schum & Gould, 2007).

Finally, study 5 addressed the question of whether a vasoconstrictor effect Zotarolimus(ABT-578)? of cilansetron in the colon might be provoked under conditions of mild colitis, given that IBS can be associated with low-grade inflammation in the colon (Bercik et al., 2005; Spiller, 2007; De Giorgio and Barbara, 2008). A preliminary account of some of the findings obtained in study 1 has been published in abstract form (Holzer et al., 2003b). Methods Animals All animal care and experimental procedures complied with the 1986 Directive of the European Communities Council and were approved by an ethics committee at the Federal Ministry of Science and Research of the Republic of Austria. The experiments were conducted in female Sprague Dawley rats (body weight: 180�C230 g) (Division of Laboratory Animal Science and Genetics, Department of Biomedical Research, Medical University of Vienna, Himberg, Austria).

Unless stated otherwise, the rats were deprived of food for 20 h before blood flow measurement, while tap water was available ad libitum. The animals were anaesthetised with phenobarbital (230 mg?kg?1 injected i.p.) between 7.00 and 8.00 am. After the loss of the righting reflex, they were placed on a thermostated table and, when surgical anaesthesia was achieved, fitted with a tracheal cannula to facilitate spontaneous respiration and to allow for the administration of hydrogen gas. A cannula in a jugular vein was used for continuous infusion of saline (1.5 mL?h?1) for dehydration of the animals to be avoided and for the i.v. administration of drugs.

Induction of mild colitis Dextran sulphate sodium (DSS, MP Biochemicals, Illkirch, France) was added to the drinking water at a concentration of 3% (w/v) for 7 days. The control animals received normal tap water. The DSS-containing drinking water was made fresh every day. For protocol consistency, the drinking bottles containing normal tap water were also renewed daily. Measurement of blood pressure and heart rate (HR) Arterial blood pressure was recorded from a cannula in a common carotid artery, and the blood pressure signal was sampled at a rate of 1 kHz and fed into a personal computer, which calculated mean arterial blood pressure (MAP) and HR online (Heinemann et al., 1998). Measurement of CBF with the hydrogen gas clearance technique The hydrogen clearance technique has been established to measure microcirculatory blood flow in the digestive tract and other tissues (Leung et al.

, 1984; Livingston et al., 1989; Brefeldin_A Holzer et al., 1991). Based on the washout of inhaled hydrogen, which clears essentially with a single passage of blood through the lungs, the hydrogen clearance method has the advantage of providing absolute estimates of microcirculatory blood flow at the position of a platinum electrode, which catalyses the dissociation of molecular hydrogen into protons and electrons (Guth and Leung, 1987).