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Abstract Background A high level of transgene expression is required, in several applications of transgenic technology. While use of strong promoters has been the main focus in such instances, 5′UTRs have also been shown to enhance transgene expression. Here, we present a 28 nt long synthetic 5′UTR (synJ), which enhances gene expression in tobacco and cotton. Results The influence of synJ on transgene expression was studied in callus cultures of cotton and different tissues of transgenic tobacco plants. The study was based on comparing the expression of reporter gene gus and gfp, with and without synJ as its 5′UTR. Mutations in synJ were also analyzed to identify the region important for enhancement. synJ, enhances gene expression by 10 to 50 fold in tobacco and cotton depending upon the tissue studied. This finding is based on the experiments comparing the expression of gus gene, encoding the synJ as 5′UTR under the control of 35S promoter with expression cassettes based on vectors like pBI121 or pRT100. Further, the enhancement was in most cases equivalent to that observed with the viral leader sequences known to enhance translation like Ω and AMV. In case of transformed cotton callus as well as in the roots of tobacco transgenic plants, the up-regulation mediated by synJ was much higher than that observed in the presence of both Ω as well as AMV. The enhancement mediated by synJ was found to be at the post-transcriptional level. The study also demonstrates the importance of a 5′UTR in realizing the full potential of the promoter strength. synJ has been utilized to design four cloning vectors: pGEN01, pBGEN02, pBGEN02-hpt and pBGEN02-ALSdm each of which can be used for cloning the desired transgene and achieving high level of expression in the resulting transgenic plants. Conclusions synJ, a synthetic 5′UTR, can enhance transgene expression under a strong promoter like 35S as well as under a weak promoter like nos in dicotyledonous plants. synJ can be incorporated as the 5′UTR of transgenes, especially in cases where high levels of expression is required. A set of vectors has also been designed to facilitate this process.

The overall goal of the Alzheimer's Disease Neuroimaging Initiative (ADNI) is to optimize and validate biomarkers for clinical trials while sharing all data and biofluid samples with the global scientific community. ADNI has been instrumental in standardizing and validating amyloid beta (Aβ) and tau positron emission tomography (PET) imaging. ADNI data were used for the US Food and Drug Administration (FDA) approval of the Fujirebio and Roche Elecsys cerebrospinal fluid diagnostic tests. Additionally, ADNI provided data for the trials of the FDA-approved treatments aducanumab, lecanemab, and donanemab. More than 6000 scientific papers have been published using ADNI data, reflecting ADNI's promotion of open science and data sharing. Despite its enormous success, ADNI has some limitations, particularly in generalizing its data and findings to the entire US/Canadian population. This introduction provides a historical overview of ADNI and highlights its significant accomplishments and future vision to pioneer "the clinical trial of the future" focusing on demographic inclusivity. HIGHLIGHTS: The Alzheimer's Disease Neuroimaging Initiative (ADNI) introduced a novel model for public-private partnerships and data sharing. It successfully validated amyloid and Tau PET imaging, as well as CSF and plasma biomarkers, for diagnosing Alzheimer's disease. ADNI generated and disseminated vital data for designing AD clinical trials., (© 2024 The Author(s). Alzheimer's & Dementia published by Wiley Periodicals LLC on behalf of Alzheimer's Association.)

MicroRNAs (miRNAs) regulate gene expression post-transcriptionally, primarily through binding sites in 3' untranslated regions (3' UTRs). While computational and biochemical approaches have been developed to predict miRNA binding sites on target messenger RNAs, reliable and high-throughput assessment of the regulatory effects of miRNAs on full-length 3' UTRs can still be challenging. Utilizing a miniaturized and high-throughput reporter assay, we present a 'pilot miRNA-targeting map', containing 4,994 successfully measured miRNA:3' UTR regulatory outputs by pairwise assays between 461 miRNAs and eleven 3' UTRs. This collection represents a large experimental miRNA:3' UTR dataset to date on a single platform. The methodology can be generally applied to studies of miRNA-mediated regulation of critical genes. We found that seedless sites can lead to substantial downregulation. We utilized this dataset in the development of a quantitative total score for modeling the total regulatory effects by both seed and seedless sites on a full-length 3' UTR. To assess the predictive value of the total score, we analyzed data from mRNA expression and proteomics studies. We found that the score can discriminate the potent miRNA inhibition from the weak inhibition and is thus useful for quantitative prediction of miRNA regulation. The score has been added to the STarMir program of the Sfold package now available via GitHub at https://github.com/Ding-RNA-Lab/Sfold., Competing Interests: Disclosure declaration The authors declare no conflict of interest.

The Alzheimer's Disease Neuroimaging Initiative (ADNI) Administrative Core oversees and coordinates all ADNI activities, to ensure the success and maximize the impact of ADNI in advancing Alzheimer's disease (AD) research and clinical trials. It manages finances and develops policies for data sharing, publications using ADNI data, and access to ADNI biospecimens. The Core develops and executes pilot projects to guide future ADNI activities and identifies key innovative methods for inclusion in ADNI. For ADNI4, the Administrative Core collaborates with the Engagement, Clinical, and Biomarker Cores to develop and evaluate novel, digital methods and infrastructure for participant recruitment, screening, and assessment of participants. The goal of these efforts is to enroll 500 participants, including > 50% from underrepresented populations, 40% with mild cognitive impairment, and 80% with elevated AD biomarkers. This new approach also provides a unique opportunity to validate novel methods. HIGHLIGHTS: The Alzheimer's Disease Neuroimaging Initiative (ADNI) Administrative Core oversees and coordinates all ADNI activities. The overall goal is to ensure ADNI's success and help design future Alzheimer's disease (AD) clinical trials. A key innovation is data sharing without embargo to maximize scientific impact. For ADNI4, novel, digital methods for recruitment and assessment were developed. New methods are designed to improve the participation of underrepresented populations., (© 2024 The Author(s). Alzheimer's & Dementia published by Wiley Periodicals LLC on behalf of Alzheimer's Association.)

Motivation: N 6 -methyladenosine (m 6 A) is the most prevalent modification in eukaryotic messenger RNAs. MicroRNAs (miRNAs) are abundant post-transcriptional regulators of gene expression. Correlation between m 6 A and miRNA-targeting sites has been reported to suggest possible involvement of m 6 A in miRNA-mediated gene regulation. However, it is unknown what the regulatory effects might be. In this study, we performed comprehensive analyses of high-throughput data on m 6 A and miRNA target binding and regulation., Results: We found that the level of miRNA-mediated target suppression is significantly enhanced when m 6 A is present on target mRNAs. The evolutionary conservation for miRNA-binding sites with m 6 A modification is significantly higher than that for miRNA-binding sites without modification. These findings suggest functional significance of m 6 A modification in post-transcriptional gene regulation by miRNAs. We also found that methylated targets have more stable structure than non-methylated targets, as indicated by significantly higher GC content. Furthermore, miRNA-binding sites that can be potentially methylated are significantly less accessible without methylation than those that do not possess potential methylation sites. Since either RNA-binding proteins or m 6 A modification by itself can destabilize RNA structure, we propose a model in which m 6 A alters local target secondary structure to increase accessibility for efficient binding by Argonaute proteins, leading to enhanced miRNA-mediated regulation., Availability and Implementation: N/A., (© The Author(s) 2022. Published by Oxford University Press.)

This trial represents the final stage of the CARESSES project which aimed to develop and evaluate a culturally competent artificial intelligent system embedded into social robots to support older adult wellbeing. A parallel group, single-blind randomised controlled trial was conducted across older adult care homes in England and Japan. Participants randomly allocated to the Experimental Group or Control Group 1 received a Pepper robot for up 18 h across 2 weeks. Two versions of the CARESSES artificial intelligence were tested: a fully culturally competent system (Experimental Group) and a more limited version (Control Group 1). Control Group 2 (Care As Usual) participants did not receive a robot. Quantitative outcomes of interest reported in the current paper were health-related quality of life (SF-36), loneliness (ULS-8), and perceptions of robotic cultural competence (CCATool-Robotics). Thirty-three residents completed all procedures. The difference in SF-36 Emotional Wellbeing scores between Experimental Group and Care As Usual participants over time was significant (F[1] = 6.614, sig = .019, η p 2  = .258), as was the comparison between Any Robot used and Care As Usual (F[1] = 5.128, sig = .031, η p 2  = .146). There were no significant changes in SF-36 physical health subscales. ULS-8 loneliness scores slightly improved among Experimental and Control Group 1 participants compared to Care As Usual participants, but this was not significant. This study brings new evidence which cautiously supports the value of culturally competent socially assistive robots in improving the psychological wellbeing of older adults residing in care settings., Competing Interests: Conflict of interestThe authors declare that they have no conflict of interest., (© The Author(s) 2021.)

Background: This article describes the design of an intervention study that focuses on whether and to what degree culturally competent social robots can improve health and well-being related outcomes among older adults residing long-term care homes. The trial forms the final stage of the international, multidisciplinary CARESSES project aimed at designing, developing and evaluating culturally competent robots that can assist older people according to the culture of the individual they are supporting. The importance of cultural competence has been demonstrated in previous nursing literature to be key towards improving health outcomes among patients., Method: This study employed a mixed-method, single-blind, parallel-group controlled before-and-after experimental trial design that took place in England and Japan. It aimed to recruit 45 residents of long-term care homes aged ≥65 years, possess sufficient cognitive and physical health and who self-identify with the English, Indian or Japanese culture ( n  = 15 each). Participants were allocated to either the experimental group, control group 1 or control group 2 (all n = 15). Those allocated to the experimental group or control group 1 received a Pepper robot programmed with the CARESSES culturally competent artificial intelligence (experimental group) or a limited version of this software (control group 1) for 18 h across 2 weeks. Participants in control group 2 did not receive a robot and continued to receive care as usual. Participants could also nominate their informal carer(s) to participate. Quantitative data collection occurred at baseline, after 1 week of use, and after 2 weeks of use with the latter time-point also including qualitative semi-structured interviews that explored their experience and perceptions further. Quantitative outcomes of interest included perceptions of robotic cultural competence, health-related quality of life, loneliness, user satisfaction, attitudes towards robots and caregiver burden., Discussion: This trial adds to the current preliminary and limited pool of evidence regarding the benefits of socially assistive robots for older adults which to date indicates considerable potential for improving outcomes. It is the first to assess whether and to what extent cultural competence carries importance in generating improvements to well-being., Trial Registration: Name of the registry: ClinicalTrials.govTrial registration number: NCT03756194.Date of registration: 28 November 2018. URL of trial registry record., Competing Interests: Competing interestsThe authors declare that they have no competing interests., (© The Author(s) 2020.)

Computational prediction of miRNA binding sites on target mRNAs facilitates experimental investigation of miRNA functions. In this chapter, we describe STarMir and STarMirDB, two application modules of the Sfold RNA package. STarMir is a Web server for performing miRNA binding site predictions for mRNA and target sequences submitted by users. STarMirDB is a database of precomputed transcriptome-scale predictions. Both STarMir and STarMirDB provide comprehensive sequence, thermodynamic, and target structure features, a logistic probability as a measure of confidence for each predicted site, and a publication-quality diagram of the predicted miRNA-target hybrid. In addition, STarMir now offers a new quantitative score to address combined regulatory effects of multiple seed and seedless sites. This score provides a quantitative measure of the overall regulatory effects of both seed and seedless sites on the target. STarMir and STarMirDB are freely available to all through the Sfold Web application server at http://sfold.wadsworth.org .

Background: Liver resection produces excellent long-term survival for patients with colorectal liver metastases but is associated with significant morbidity and mortality from ischaemia reperfusion injury (IRI). Remote ischaemic preconditioning (RIPC) can reduce the effect of IRI. This pilot randomised controlled trial evaluated RIPC in patients undergoing major hepatectomy at the Royal Free Hospital, London., Methods: Sixteen patients were randomised to RIPC or sham control. RIPC was induced through three 10-min cycles of alternate ischaemia and reperfusion to the leg. At baseline and immediately post-resection, transaminases and indocyanine green (ICG) clearance were measured., Findings: The RIPC group had lower ALT and AST levels immediately post-resection (ALT: 43% lower 497 ± 165 vs 889 ± 170 IU/L; p = 0.019 AST: 54% lower 408 ± 166 vs 836 ± 167 IU/L; p = 0.001) and at 24 h (ALT: 41% lower 412 ± 144 vs 698 ± 137 IU/L; p = 0.026 AST: 50% lower 316 ± 116 vs 668 ± 115 IU/L; p = 0.02). ICG clearance was reduced in controls versus RIPC immediately after resection (ICG-PDR: 11.1 ± 1.1 vs 16.5 ± 1.4%/min; p = 0.035)., Conclusions: This pilot study shows that RIPC has potential to reduce liver injury following hepatectomy justifying a prospective RCT powered to demonstrate clinical benefits.

Mature microRNAs (miRNAs) are processed from hairpin-containing primary miRNAs (pri-miRNAs). However, rules that distinguish pri-miRNAs from other hairpin-containing transcripts in the genome are incompletely understood. By developing a computational pipeline to systematically evaluate 30 structural and sequence features of mammalian RNA hairpins, we report several new rules that are preferentially utilized in miRNA hairpins and govern efficient pri-miRNA processing. We propose that a hairpin stem length of 36 ± 3 nt is optimal for pri-miRNA processing. We identify two bulge-depleted regions on the miRNA stem, located ∼16-21 nt and ∼28-32 nt from the base of the stem, that are less tolerant of unpaired bases. We further show that the CNNC primary sequence motif selectively enhances the processing of optimal-length hairpins. We predict that a small but significant fraction of human single-nucleotide polymorphisms (SNPs) alter pri-miRNA processing, and confirm several predictions experimentally including a disease-causing mutation. Our study enhances the rules governing mammalian pri-miRNA processing and suggests a diverse impact of human genetic variation on miRNA biogenesis., (© 2017 Roden et al.; Published by Cold Spring Harbor Laboratory Press.)

microRNAs (miRNAs) are an abundant class of small endogenous non-coding RNAs (ncRNAs) of ∼22 nucleotides (nts) in length. These small regulatory molecules are involved in diverse developmental, physiological and pathological processes. miRNAs target mRNAs (mRNAs) for translational repression and/or mRNA degradation. Predictions of miRNA binding sites facilitate experimental validation of miRNA targets. Models developed with data from CLIP studies have been used for predictions of miRNA binding sites in the whole transcriptomes of human, mouse and worm. The prediction results have been assembled into STarMirDB, a new database of miRNA binding sites available at http://sfold.wadsworth.org/starmirDB.php . STarMirDB can be searched by miRNAs or mRNAs separately or in combination. The search results are categorized into seed and seedless sites in 3' UTR, CDS and 5' UTR. For each predicted site, STarMirDB provides a comprehensive list of sequence, thermodynamic and target structural features that are known to influence miRNA: target interaction. A high resolution PDF diagram of the conformation of the miRNA:target hybrid is also available for visualization and publication. The results of a database search are available through both an interactive viewer and downloadable text files.

MicroRNAs (miRNAs) are a class of endogenous short noncoding RNAs that regulate gene expression by targeting messenger RNAs (mRNAs), which results in translational repression and/or mRNA degradation. As regulatory molecules, miRNAs are involved in many mammalian biological processes and also in the manifestation of certain human diseases. As miRNAs play central role in the regulation of gene expression, understanding miRNA-binding patterns is essential to gain an insight of miRNA mediated gene regulation and also holds promise for therapeutic applications. Computational prediction of miRNA binding sites on target mRNAs facilitates experimental investigation of miRNA functions. This chapter provides protocols for using the STarMir web server for improved predictions of miRNA binding sites on a target mRNA. As an application module of the Sfold RNA package, the current version of STarMir is an implementation of logistic prediction models developed with high-throughput miRNA binding data from cross-linking immunoprecipitation (CLIP) studies. The models incorporated comprehensive thermodynamic, structural, and sequence features, and were found to make improved predictions of both seed and seedless sites, in comparison to the established algorithms (Liu et al., Nucleic Acids Res 41:e138, 2013). Their broad applicability was indicated by their good performance in cross-species validation. STarMir is freely available at http://sfold.wadsworth.org/starmir.html .

Genetic variations within microRNA (miRNA) binding sites can affect miRNA-mediated gene regulation, which may lead to phenotypes and diseases. We perform a transcriptome-scale analysis of genetic variants and miRNA:target interactions identified by CLASH. This analysis reveals that rare variants tend to reside in CDSs, whereas common variants tend to reside in the 3' UTRs. miRNA binding sites are more likely to reside within those targets in the transcriptome with lower variant densities, especially target regions in which nucleotides have low mutation frequencies. Furthermore, an overwhelming majority of genetic variants within or near miRNA binding sites can alter not only the potential of miRNA:target hybridization but also the structural accessibility of the binding sites and flanking regions. These suggest an interpretation for certain associations between genetic variants and diseases, i.e. modulation of miRNA-mediated gene regulation by common or rare variants within or near miRNA binding sites, likely through target structure alterations. Our data will be valuable for discovering new associations among miRNAs, genetic variations and human diseases., (© The Author(s) 2014. Published by Oxford University Press on behalf of Nucleic Acids Research.)

STarMir web server predicts microRNA (miRNA) binding sites on a target ribonucleic acid (RNA). STarMir is an implementation of logistic prediction models developed with miRNA binding data from crosslinking immunoprecipitation (CLIP) studies (Liu,C., Mallick, B., Long, D., Rennie, W.A., Wolenc, A., Carmack, C.S. and Ding, Y. (2013). CLIP-based prediction of mammalian microRNA binding sites. Nucleic Acids Res., 41(14), e138). In both intra-dataset and inter-dataset validations, the models showed major improvements over established algorithms in predictions of both seed and seedless sites. General applicability of the models was indicated by good performance in cross-species validations. The input data for STarMir is processed by the web server to perform prediction of miRNA binding sites, compute comprehensive sequence, thermodynamic and target structure features and a logistic probability as a measure of confidence for each predicted site. For each of seed and seedless sites and for all three regions of a mRNA (3' UTR, CDS and 5' UTR), STarMir output includes the computed binding site features, the logistic probability and a publication-quality diagram of the predicted miRNA:target hybrid. The prediction results are available through both an interactive viewer and downloadable text files. As an application module of the Sfold RNA package (http://sfold.wadsworth.org), STarMir is freely available to all at http://sfold.wadsworth.org/starmir.html., (© The Author(s) 2014. Published by Oxford University Press on behalf of Nucleic Acids Research.)

Several reports of promoters from plants, viral and artificial origin that confer high constitutive expression are known. Among these the CaMV 35S promoter is used extensively for transgene expression in plants. We identified candidate promoters from Arabidopsis based on their transcript levels (meta-analysis of available microarray control datasets) to test their activity in comparison to the CaMV 35S promoter. A set of 11 candidate genes were identified which showed high transcript levels in the aerial tissue (i.e. leaf, shoot, flower and stem). In the initial part of the study binary vectors were developed wherein the promoter and 5'UTR region of these candidate genes (Upstream Regulatory Module, URM) were cloned upstream to the reporter gene β glucuronidase (gus). The promoter strengths were tested in transformed callus of Nicotiana tabacum and Gossypium hirsutum. On the basis of the results obtained from the callus, the influence of the URM cassettes on transgene expression was tested in transgenic tobacco. The URM regions of the genes encoding a subunit of photosystem I (PHOTO) and geranyl geranyl reductase (GGR) in A. thaliana genome showed significantly high levels of GUS activity in comparison to the CaMV 35S promoter. Further, when the 5'UTRs of both the genes were placed downstream to the CaMV 35S promoter it led to a substantial increase in GUS activity in transgenic tobacco lines and cotton callus. The enhancement observed was even higher to that observed with the viral leader sequences like Ω and AMV, known translational enhancers. Our results indicate that the two URM cassettes or the 5'UTR regions of PHOTO and GGR when placed downstream to the CaMV 35S promoter can be used to drive high levels of transgene expression in dicotyledons.

MicroRNAs (miRNAs) are post-transcriptional regulators of gene expression. Since the discovery of lin-4, the founding member of the miRNA family, over 360 miRNAs have been identified for Caenorhabditis elegans (C. elegans). Prediction and validation of targets are essential for elucidation of regulatory functions of these miRNAs. For C. elegans, crosslinking immunoprecipitation (CLIP) has been successfully performed for the identification of target mRNA sequences bound by Argonaute protein ALG-1. In addition, reliable annotation of the 3' untranslated regions (3' UTRs) as well as developmental stage-specific expression profiles for both miRNAs and 3' UTR isoforms are available. By utilizing these data, we developed statistical models and bioinformatics tools for both transcriptome-scale and developmental stage-specific predictions of miRNA binding sites in C. elegans 3' UTRs. In performance evaluation via cross validation on the ALG-1 CLIP data, the models were found to offer major improvements over established algorithms for predicting both seed sites and seedless sites. In particular, our top-ranked predictions have a substantially higher true positive rate, suggesting a much higher likelihood of positive experimental validation. A gene ontology analysis of stage-specific predictions suggests that miRNAs are involved in dynamic regulation of biological functions during C. elegans development. In particular, miRNAs preferentially target genes related to development, cell cycle, trafficking, and cell signaling processes. A database for both transcriptome-scale and stage-specific predictions and software for implementing the prediction models are available through the Sfold web server at http://sfold.wadsworth.org.

Hepatic ischaemia reperfusion injury (IRI) lowers hepatic oxygenation and induces tissue acidosis. Remote ischaemic preconditioning (RIPC) reduces hepatic IRI through increased hepatic blood flow but its effect on hepatic oxygenation and acidosis is not known. This study investigates these effects through near infrared spectroscopy (NIRS). Twenty-four NZ rabbits were grouped into four: sham, RIPC, IRI alone, RIPC + IRI. RIPC was induced through three cycles of 10 min ischaemia and reperfusion to the limb. Total hepatic ischaemia was produced by complete portal inflow occlusion for 25 min. Serum transaminases, bicarbonate and hepatic venous nitrite/nitrate (NO(x) ) levels were measured 2 h postreperfusion. Hepatic oxygenation was monitored with NIRS. At 2 h post reperfusion, IRI alone resulted in reduced mitochondrial oxygenation (CytOx CuA Redox), serum bicarbonate, hepatic venous NO(x) with an increase in serum transaminases and hepatic deoxyhaemoglobin levels. RIPC before IRI caused significant improvement in mitochondrial oxygenation (P = 0.01), increased serum bicarbonate (P = 0.02), hepatic venous NO(x) (P = 0.025) with a decrease in serum transaminases (P = 0.04) and hepatic deoxyhaemoglobin levels (P = 0.03). There was a positive correlation (P = 0.02) between hepatic venous NO(x) levels and mitochondrial oxygenation. RIPC before IRI improves hepatic mitochondrial oxygenation and reduces acidosis and currently undergoing clinical study., (© 2012 The Authors. Transplant International © 2012 European Society for Organ Transplantation.)

High levels of expression of the cry1Ac gene from Bacillus thuringiensis cannot be routinely achieved in transgenic plants despite modifications made in the gene to improve its expression. This has been attributed to the instability of the transcript in a few reports. In the present study, based on the genetic transformation of cotton and tobacco, we show that the expression of the Cry1Ac endotoxin has detrimental effects on both the in vitro and in vivo growth and development of transgenic plants. A number of experiments on developing transgenics in cotton with different versions of cry1Ac gene showed that the majority of the plants did not express any Cry1Ac protein. Based on Southern blot analysis, it was also observed that a substantial number of lines did not contain the cry1Ac gene cassette although they contained the marker gene nptII. More significantly, all the lines that showed appreciable levels of expression were found to be phenotypically abnormal. Experiments on transformation of tobacco with different constructs expressing the cry1Ac gene showed that in vitro regeneration was inhibited by the encoded protein. Further, out of a total of 145 independent events generated with the different cry1Ac gene constructs in tobacco, only 21 showed expression of the Cry1Ac protein, confirming observations made in cotton that regenerants that express high levels of the Cry1Ac protein are selected against during regeneration of transformed events. This problem was circumvented by targeting the Cry1Ac protein to the chloroplast, which also significantly improved the expression of the protein.

Femoral arterial lines are used for continuous monitoring of arterial blood pressure in experimental studies. However, placement of a catheter in the femoral artery could produce acute limb ischemia with associated systemic effects. The aim of this study was to investigate the effect of femoral arterial line insertion on liver function, in a rabbit liver lobar ischemia-reperfusion (I/R) model. Four groups of animals (n = 6 each) were studied: groups 1 and 2 (sham) underwent laparotomy but no liver ischemia. In groups 3 and 4 (I/R), liver lobar ischemia was induced for 60 minutes followed by 7 hours of reperfusion. In groups 1 and 3, the arterial line was placed in the femoral artery whereas in groups 2 and 4 in the ear artery. Liver function was assessed by serum alanine aminotransferase (ALT) activity, bile flow, plasma lactate levels, and histology. Results are expressed as mean +/- SEM. Alanine aminotransferase activity and lactate levels were significantly higher in the I/R femoral line group compared with the I/R ear line group at 7 hours postreperfusion. Bile production was significantly lower (75 +/- 9.6 vs 112 +/- 10 microL/min per 100 g liver weight). Histopathology showed more extensive hepatocellular necrosis and neutrophil accumulation in the I/R femoral line group compared with I/R ear line group. The sham femoral group showed liver injury, which was more marked than the ear line group (all P < .05). In conclusion, femoral artery cannulation induces remote liver injury. The use of femoral arterial lines should be avoided in experimental studies concerning liver function.

Ischemia reperfusion injury (IRI) results in damage to local and remote organs. Remote ischemic preconditioning (RIPC) is a strategy to protect against IRI by inducing a prior brief period(s) of IRI to an organ remote from that undergoing sustained injury. RIPC has been shown to protect organs against IRI; however, the protocols and mechanisms for RIPC are unclear. For this review, a Medline/Pubmed search (January 1985 to January 2007) was conducted and all relevant articles were included. RIPC protocols are organ and species specific and both humoral and neurogenic pathways are involved in triggering intracellular signal pathways for protection.

Steatotic livers are highly susceptible to I/R (ischaemia/reperfusion) injury and, therefore, the aim of the present study was to evaluate the in vivo effect of NAC (N-acetylcysteine) on hepatic function in the early and initial late phase of warm liver I/R injury in steatotic rabbits. Twelve New Zealand White rabbits were fed a high-cholesterol (2%) diet. The control group (n=6) underwent lobar liver ischaemia for 1 h, followed by 6 h of reperfusion. In the treated group receiving NAC (n=6), an intravenous infusion of NAC was administered prior to and during the 6 h reperfusion period. Systemic and hepatic haemodynamics were monitored continuously. ALT (alanine aminotransferase) activity and bile production were measured. NMR spectroscopy was used to analyse bile composition. Oxidation of DHR (dihydrorhodamine) to RH (rhodamine) was used as a marker of production of reactive oxygen and nitrogen species. Moderate centrilobular hepatic steatosis was demonstrated by histology. The results showed that NAC administration significantly improved portal flow, hepatic microcirculation, bile composition and bile flow after 5 h of reperfusion. NAC administration was also associated with less hepatocellular injury, as indicated by ALT serum activity, and decreased the oxidation of DHR to RH. In conclusion, NAC administration decreased the extent of I/R injury in the steatotic liver, particularly during the late phase of reperfusion.