What motivates students to decrease or cease substance use?: A scoping review.

OBJECTIVE: The association between illicit substance use by third-level education students and their mental and physical health is well documented. The aim of this scoping review was to determine factors that contribute to student motivations to reduce or stop their use of illicit substances, and to elaborate on factors that may be pertinent for student-focused behaviour change interventions for substance use. METHOD: We searched eight databases in March 2021 using search terms based on 'students', 'illicit substance use', and 'motivations'. We identified 86 research articles that reported on third-level education students' illicit substance use and included reasons or motives for their use. RESULTS: After full-text screening, three studies were eligible for inclusion in the qualitative synthesis. The majority of studies described motives for abstention but did not describe motivation for reducing or stopping current patterns of use of illicit substances. CONCLUSION: Few studies have examined motivations of third-level education students to decrease or cease substance use. Promising avenues for research on motivations to change substance use behaviour include the social contextual factors, perceived effects on social relationships, and actions of friends and family to prompt contemplations of change.

A clinical approach strategy for the diagnosis, treatment and evaluation of external cervical resorption.

AIM: To propose a clinical approach strategy on the diagnosis, treatment and evaluation of external cervical tooth resorption (ECR) cases. To investigate and discuss the outcome of this approach. METHODOLOGY: A clinical approach strategy on ECR was developed based on a retrospective observation study of 542 teeth. Forty-seven teeth were excluded due to lack of clinical/radiographical information, and 182 were immediately extracted. This approach had three steps: diagnosis, treatment planning and evaluation. During diagnosis, the medical, dental history and clinical/radiographical characteristics were evaluated. Depending on the resorption extent, ECR cases were categorized into four classes according to Heithersay's classification. During treatment planning, a treatment decision flowchart was prepared based on four main decisive criteria: probing feasibility, pain, location and extent of resorption (class), and existence of bone-like tissue. Three treatment options were applied: (a) extraction, (b) monitoring or (c) conservative treatment by external, internal or combination of internal-external treatments. During evaluation, assessment of ECR progression, tooth survival and other factors like aesthetics and periodontal attachment were performed. Descriptive statistical analysis of the outcome for up to 10 years (for the overall clinical approach and for each individual treatment decision), was carried out with OriginLabs OriginPro 9 and Microsoft Excel 365. RESULTS: A three-step strategy was developed on how to deal with ECR cases. Indicative examples of each treatment decision were presented and discussed. The overall survival rate of this strategy was 84.6% (3 years), 70.3% (5 years), 42.7% (8 years) and 28.6% (10 years). Higher survival rate was observed for external treatment decision than for internal. The success of each treatment decision depended on the extent of the resorption (class). The success of a treatment decision should be based on the long-term outcome, as a different evolution can be observed with time. CONCLUSIONS: A clinical approach strategy was introduced on ECR pathosis. This strategy was not solely based on ECR class, as other important decisive criteria were considered. This step-wise approach, has a 70.3% survival rate with a mean of 5 years. This work will hopefully provide an incentive for a broader collaboration, to potentially establish a universally accepted ECR treatment strategy.

Outcomes of tuberculosis treatment in a tertiary health facility in north-central Nigeria

Background: Tuberculosis (TB) remains a major public health concern despite being a curable and preventable disease. The treatment of TB using a cocktail of drugs over a period of six months under the directly observed treatment short-course strategy has led to a reduction in cases but is plagued by some challenges that leads to unsuccessful or poor outcomes, which can ultimately result in spread of infections, development of drug resistance and increase in morbidity and mortality. The objectives of this study are to determine outcomes of TB treatment in Dalhatu Araf Specialist Hospital, Lafia, Nasarawa State, Nigeria and the factors that may be associated with the outcomes. Methodology: This was a retrospective study using the medical records of patients who were registered for TB treatment over a five-year period between 2016 to 2020. Data from TB registers including demographic and relevant clinical information, and treatment outcomes, were extracted into a structured data extraction format, and analysed with SPSS version 21.0 software package. Univariate and bivariate analyses were conducted, and Chi square test was used to determine association between TB outcomes and independent variables at 95% confidence interval and p<0.05 was considered as the significant value. Results: Records of 1,313 patients were studied, 744 (56.7%) were males while 569 (43.3%) were females. The age range of the patients was ≤ 1 year - 96 years, with a mean age of 30±16.7 years. Most were pulmonary TB cases (88.8%, n=1,166), newly diagnosed (95.5%, n=1254), and human immunodeficiency virus (HIV) negative at the time of TB diagnosis (63.7%, n=837). Eight hundred and seven (61.5%) patients had successful treatment, and 34% (n=446) had unsuccessful outcomes made of 'loss to follow-up' 25.8% (n=339), deaths 7.8% (n=102) and treatment failure 0.4% (n=5), while 2.3% (n=30) were transferred out and 2.3% (n=30) removed from TB register. Treatment success rate was significantly higher in patients with pulmonary TB (p=0.0024), residents in Lafia LGA (p=0.0005), those treated in 2016 (p=0.0006) and bacteriologically confirmed cases (p<0.0001), while death rate was significantly lower among patients who were HIV-negative at the time of TB diagnosis (p<0.0001). Conclusion: TB treatment success rate in this study fell short of the WHO average rate. High rates of 'loss to followup' and deaths in this study is a wake-up call to all stakeholders in the facility and the State to put in place measures to reduce poor outcomes of TB treatment.

The draft genome sequence of the grove snail Cepaea nemoralis.

Studies on the shell color and banding polymorphism of the grove snail Cepaea nemoralis and the sister taxon Cepaea hortensis have provided compelling evidence for the fundamental role of natural selection in promoting and maintaining intraspecific variation. More recently, Cepaea has been the focus of citizen science projects on shell color evolution in relation to climate change and urbanization. C. nemoralis is particularly useful for studies on the genetics of shell polymorphism and the evolution of "supergenes," as well as evo-devo studies of shell biomineralization, because it is relatively easily maintained in captivity. However, an absence of genomic resources for C. nemoralis has generally hindered detailed genetic and molecular investigations. We therefore generated ∼23× coverage long-read data for the ∼3.5 Gb genome, and produced a draft assembly composed of 28,537 contigs with the N50 length of 333 kb. Genome completeness, estimated by BUSCO using the metazoa dataset, was 91%. Repetitive regions cover over 77% of the genome. A total of 43,519 protein-coding genes were predicted in the assembled genome, and 97.3% of these were functionally annotated from either sequence homology or protein signature searches. This first assembled and annotated genome sequence for a helicoid snail, a large group that includes edible species, agricultural pests, and parasite hosts, will be a core resource for identifying the loci that determine the shell polymorphism, as well as in a wide range of analyses in evolutionary and developmental biology, and snail biology in general.

Morphological and phylogenetic diversity of Waminoa and similar flatworms (Acoelomorpha) in the western Pacific Ocean.

The genus Waminoa currently contains two described species, which each contains two types of endosymbiotic algae. Waminoa individuals are basically brown in body color, derived from these algal symbionts, and their body shape has been described as "discoid to obcordate". They have been found as associates of various anthozoans (Cnidaria) in the Indo-Pacific Ocean and the Red Sea. In order to reveal the diversity of the genus Waminoa and their hosts, we conducted phylogenetic and morphological analyses on acoelomate flatworms specimens collected from Japan, Palau and Indonesia. At least 18 Waminoa morphotypes were found on at least 20 anthozoan host species, and two specimens were found on species of two sea stars. Overall, there were two main body shapes of specimens; obcordate, as seen in W. litus and W. brickneri, and the other molar-like with an elongated body. These two body shapes each represented a separate clade in 18S rDNA and mitochondrial cytochrome c oxidase subunit 1 (COI) phylogenetic trees, with W. brickneri included in the obcordate subclade. Automatic Barcode Gap Discovery (ABGD) analyses on COI sequences of our specimens revealed the presence of at least five operational taxonomic units (OTUs). These five OTUs consisted of one large group of all obcordate animals, three OTUs consisting of one specimen each within the molar-like clade, and one large group of the remaining molar-like specimens. Both clades contain numerous morphotypes and were associated with a variety of hosts. Finally, based on genetic distances, the molar-like specimens are considered as an unnamed genus group separate from Waminoa, which needs to be clarified in future studies.

Quantitative surface-enhanced Raman spectroscopy of single bases in oligodeoxynucleotides.

To address the question of whether the SERS signals of ss-DNA are simply combinations of the signals from the individual bases that comprise the sequence, SERS spectra of unmodified ss-DNA sequences were obtained using a hydroxylamine-reduced Ag colloid aggregated with MgSO4. Initially, synthetic oligodeoxynucleotides with systematic structural variations were used to investigate the effect of adding single nucleobases to the 3' terminus of 10-mer and 20-mer sequences. It was found that the resulting SERS difference spectra could be used to identify the added nucleobases since they closely matched reference spectra of the same nucleobase. Investigation of the variation in intensity of an adenine probe which was moved along a test sequence showed there was a small end effect where nucleobases near the 3' terminus gave slightly larger signals but the effect was minor (30%). More significantly, in a sample set comprising 25-mer sequences where A, T or G nucleobases were substituted either near the centres of the sequences or the 5' or 3' ends, the SERS difference spectra only matched the expected form in approximately half the cases tested. This variation appeared to be due to changes in secondary structure induced by altering the sequences since uncoiling the sequences in a thermal pre-treatment step gave difference spectra which in all cases matched the expected form. Multivariate analysis of the set of substitution data showed that 99% of the variance could be accounted for in a model with just three factors whose loadings matched the spectra of the A, T, and G nucleobases and which contained no positional information. This suggests that aside from the differences in secondary structure which can be eliminated by thermal pre-treatment, the SERS spectra of the 25-mers studied here are simply the sum of their component parts. Although this means that SERS provides very little information on the primary sequence it should be excellent for the detection of post-transcription modifications to DNA which can occur at multiple positions along a given sequence.

A systematic review of associations between environmental exposures and development of asthma in children aged up to 9 years.

OBJECTIVES: Childhood asthma is a complex condition where many environmental factors are implicated in causation. The aim of this study was to complete a systematic review of the literature describing associations between environmental exposures and the development of asthma in young children. SETTING: A systematic review of the literature up to November 2013 was conducted using key words agreed by the research team. Abstracts were screened and potentially eligible papers reviewed. Papers describing associations between exposures and exacerbation of pre-existing asthma were not included. Papers were placed into the following predefined categories: secondhand smoke (SHS), inhaled chemicals, damp housing/mould, inhaled allergens, air pollution, domestic combustion, dietary exposures, respiratory virus infection and medications. PARTICIPANTS: Children aged up to 9 years. PRIMARY OUTCOMES: Diagnosed asthma and wheeze. RESULTS: 14,691 abstracts were identified, 207 papers reviewed and 135 included in the present review of which 15 were systematic reviews, 6 were meta-analyses and 14 were intervention studies. There was consistent evidence linking exposures to SHS, inhaled chemicals, mould, ambient air pollutants, some deficiencies in maternal diet and respiratory viruses to an increased risk for asthma (OR typically increased by 1.5-2.0). There was less consistent evidence linking exposures to pets, breast feeding and infant dietary exposures to asthma risk, and although there were consistent associations between exposures to antibiotics and paracetamol in early life, these associations might reflect reverse causation. There was good evidence that exposures to house dust mites (in isolation) was not associated with asthma risk. Evidence from observational and intervention studies suggest that interactions between exposures were important to asthma causation, where the effect size was typically 1.5-3.0. CONCLUSIONS: There are many publications reporting associations between environmental exposures and modest changes in risk for asthma in young children, and this review highlights the complex interactions between exposures that further increase risk.

Replicate divergence between and within sounds in a marine fish: the copper rockfish (Sebastes caurinus).

Understanding the factors that influence larval dispersal and connectivity among marine populations is critical to the conservation and sustainable management of marine resources. We assessed genetic subdivision among ten populations of copper rockfish (Sebastes caurinus) representing paired samples of outer coast and the heads of inlets in five replicate sounds on the west coast of Vancouver Island, British Columbia, using 17 microsatellite DNA loci. Overall, subdivision (F(ST)) was low (F(ST) = 0.031, P < 0.001), but consistently higher between paired coast and head of inlet sites (mean FST = 0.047, P < 0.001) compared to among the five coast sites (mean F(ST) = -0.001, P > 0.5) or among the five head of inlet sites (mean F(ST) = 0.026, P < 0.001). Heterozygosity, allelic richness and estimates of effective population size were also lower in head of inlet sites than in coast sites. Bayesian analysis identified two genetic groups across all samples, a single genetic group among only coast samples, two genetic groups among head of inlet samples and two genetic groups within each sound analysed separately. Head of inlet copper rockfish tended to be shorter with lower condition factors and grew more slowly than coast sites fish. Reduced physical connectivity and selection against immigrants in contrasting outer coast-head of inlet environments likely contribute to the evolution of population structure of copper rockfish. Based on genetic connectivity, coast sites appear to be better served by existing marine protected areas than are head of inlet sites.

Suboptimal consideration and management of potential familial hypercholesterolaemia in patients with suspected premature coronary artery disease.

INTRODUCTION: Familial hypercholesterolaemia (FH) is caused by an autosomal dominant mutation of the low density lipoprotein (LDL) receptor gene, resulting in high levels of LDL cholesterol and premature coronary artery disease (P-CAD). Studies have shown low detection rates of FH in patients admitted with P-CAD and suboptimal therapy at discharge. METHODS: Males aged ≤ 55 years and females aged ≤ 60 years who were admitted with P-CAD to the Gold Coast Hospital during a 12-month period were included in the study. The demographics, cardiovascular risk factors, examination findings, admission and discharge cardiac medications and provisional diagnoses were recorded. Diagnosis of FH was made according to internationally accepted criteria. RESULTS: 210 patients were included in the study; 60% were male and 40% female (mean age 48 and 50 years, respectively). Only 96 (46%) patients' fasting lipid levels were documented (LDL-C 2.75 ± 1.0 mmol/L), and FH was considered in three (1%) cases. According to the Dutch Lipid Network criteria, three (1%) patients had probable FH, 50 (24%) had possible FH and 60 (29%) had unlikely FH. Of the 53 patients with probable or possible FH, 12 (23%) were discharged without statin therapy and 13 (25%) on the maximum recommended statin dose. CONCLUSION: Our study has found inadequate documentation and screening for FH and suboptimal therapy in patients admitted with P-CAD. We propose a simple screening tool that can be applied to all patients admitted with suspected P-CAD in order to improve the detection rate of FH and its management.

The complete mitogenome of Cylindrus obtusus (Helicidae, Ariantinae) using Illumina next generation sequencing.

BACKGROUND: This study describes how the complete mitogenome of a terrestrial snail, Cylindrus obtusus (Draparnaud, 1805) was sequenced without PCRs from a collection specimen that had been in 70% ethanol for 8 years. The mitogenome was obtained with Illumina GAIIx shot gun sequencing. Although the used specimen was collected relatively recently and kept in a DNA-friendly preservative (not formalin as frequently used with old museum specimens), we believe that the exclusion of PCRs as facilitated by NGS (Next Generation Sequencing) removes a great obstacle in DNA sequencing of collection specimens. A brief comparison is made between our Illumina GAIIx approach and a similar study that made use of the Roche 454-FLX platform. RESULTS: The mtDNA sequence of C. obtusus is 14,610 bases in length (about 0.5 kb larger than other stylommatophoran mitogenomes reported hitherto) and contains the 37 genes (13 protein coding genes, two rRNAs and 22 tRNAs) typical for metazoans. Except for a swap between the position of tRNA-Pro and tRNA-Ala, the gene arrangement of C. obtusus is identical to that reported for Cepaea nemoralis. The 'aberrant' rearrangement of tRNA-Thr and COIII compared to that of other Sigmurethra (and the majority of gastropods), is not unique for C. nemoralis (subfamily Helicinae), but is also shown to occur in C. obtusus (subfamily Ariantinae) and might be a synapomorphy for the family Helicidae. CONCLUSIONS: Natural history collections potentially harbor a wealth of information for the field of evolutionary genetics, but it can be difficult to amplify DNA from such specimens (due to DNA degradation for instance). Because NGS techniques do not rely on primer-directed amplification (PCR) and allow DNA to be fragmented (DNA gets sheared during library preparation), NGS could be a valuable tool for retrieving DNA sequence data from such specimens. A comparison between Illumina GAIIx and the Roche 454 platform suggests that the former might be more suited for de novo sequencing of mitogenomes.

Expression of the non-neuronal cholinergic system in rat ß-cells.

Various markers of the cholinergic system (like e.g. choline acetyltransferase) were demonstrated by immunohistochemistry in, seemingly, ß-cells of rat pancreas. The findings may suggest an autocrine role of acetylcholine for the ß-cells.

Reappraisal of the "Molecular phylogeny of Western Palaearctic Helicidae s.l. (Gastropoda: Stylommatophora)": when poor science meets GenBank.

A paper on the 'Molecular phylogeny of Western Palaearctic Helicidae s.l.', published by Steinke et al. (2004) in this journal, is critically analysed. Several obvious errors are corrected and methodological weaknesses are revealed. BLAST searches on the sequences published in that paper and now in GenBank, showed high percentages of similarity of the alleged species with taxa that are considered only distantly related in the literature. Inspection of the so-called voucher specimens showed that some shells were misidentified, whereas others contained dirt or were bleached, indicating that these had been collected empty. Obviously the sequences published for those species could not have originated from those specimens, which cannot be considered vouchers therefore, even if they are from the same locality. In other instances, spurious sequences were published for correctly identified voucher specimens. For several species for which we collected specimens ourselves, the COI or the 16S sequence, or both, clearly differed from the results published by Steinke et al. The consequences of our results for the molecular data on helicid gastropods and their classification are listed.

Using DNA-barcoding to make the necrobiont beetle family Cholevidae accessible for forensic entomology.

The beetle family Cholevidae (Coleoptera: Staphylinoidea), sometimes viewed as the subfamily Cholevinae of the Leiodidae, consists of some 1700 species worldwide. With the exception of specialized cave-dwelling species and species living in bird and mammal nests and burrows, the species are generalized soil-dwellers that, at least in temperate regions, are mostly found on vertebrate cadavers. Although they have been regularly reported from human corpses, and offer potential because of many species' peak activity in the cold season, they have not been a focus of forensic entomologists so far. This is probably due to their small size and the difficulty in identifying the adults and their larvae. In this paper, we show that DNA-barcoding can help make this group of necrobiont beetles available as a tool for forensic research. We collected 86 specimens of 20 species of the genera Catops, Fissocatops, Apocatops, Choleva, Nargus, Ptomaphagus, and Sciodrepoides from the Netherlands and France and show that a broad "barcoding gap" allows almost all species to be easily and unambiguously identified by the sequence of the "barcoding gene" cytochrome c oxidase I (COI). This opens up the possibility of adding Cholevidae to the set of insect taxa routinely used in forensic entomology.

Is acetylcholine a signaling molecule for human colon cancer progression?

OBJECTIVE: Non-neuronal acetylcholine (ACh) has been suggested to be a mediator for the development of various types of cancer. We analyzed a possible role for this molecule in carcinogenesis and/or progression of human colon cancer, in patient biopsies harvested from the colon during surgery. We addressed whether ACh synthesis (by choline acetyltransferase) and/or degradation (by ACh esterase), as well as the expression of the α7-subtype of the nicotinic ACh receptors, and the peptide ligand at the α7 receptors, secreted mammalian Ly6/urokinase-type plasminogen activator receptor-related protein-1, respectively, are deranged in tumor tissue as compared with macroscopically tumor-free colon tissue. METHODS: A total of 38 patients were grouped for analysis based on their respective Dukes stage (either Dukes A + B or C + D). A mucosal tissue sample was harvested from macroscopically tumor-free colon tissue (i.e. control tissue), as well as from the tumor, and protein lysates were prepared for quantitative Western blotting. Full-thickness specimens were taken for immunohistochemistry. RESULTS: For all the above named markers, there was a significant difference between control and tumor tissue with regard to protein levels, and there was, in addition, a significant difference in protein levels between the Dukes A + B and C + D groups. CONCLUSION: The current findings may suggest a role for ACh in colon carcinogenesis/cancer progression; the data obtained could have prognostic and/or therapeutic significance for this disease.

A pharmacological analysis of the cholinergic regulation of urokinase-type plasminogen activator secretion in the human colon cancer cell line, HT-29.

Urokinase-type plasminogen activator (uPA) is an important factor for tumour cell invasion and metastasis. We recently showed that acetylcholine is an autocrine/paracrine growth factor for the human colon cancer cell line, HT-29, in part via the α7 subtype of the nicotinic acetylcholine receptors. In the current study, we investigated whether acetylcholine participates in the regulation of the protein expressions of also uPA and its receptor (uPAR) in the HT-29 cell line. Such were investigated by immunocytochemistry and Western blotting, and quantitation of uPA secretion was undertaken by ELISA. Stimulation of the cells for 24h with nicotine caused increased uPA secretion with peak effect (78% above the control) occurring at a nicotine concentration of 10nM. This effect was markedly inhibited by α-Bungarotoxin, thus showing the involvement of α7 nicotinic acetylcholine receptors. Basal uPA secretion was found to be partly dependent on ongoing activation of nicotinic receptors, suggesting tonic production of acetylcholine. Conversely, there was no cholinergic influence on the expression of uPAR. The current findings demonstrate novel aspects of receptor-mediated regulation of tumour metastatic potential via uPA secretion. This may suggest future pharmaceutical strategies in treatment of colorectal cancer.

The influence of opioids on urokinase plasminogen activator on protein and mRNA level in MCF-7 breast cancer cell line.

Urokinase plasminogen activator plays a key role in tumor-associated processes, increasing cancer cell invasion and metastasis, and is therefore used as a marker in cancer prognosis. In this study, we have determined the effect of mu-opioid receptor agonists and antagonists on the urokinase plasminogen activator secretion in MCF-7 cell line. It was shown that mu-opioid receptor agonists, such as morphine and endomorphins, greatly stimulate urokinase plasminogen activator secretion, while naloxone and MOR-selective antagonists elicit the opposite effect. The same tendency was observed also on the urokinase plasminogen activator mRNA level. However, neither agonists nor antagonists had any effect on proliferation of MCF-7 cells. The findings reported in this study may be useful in designing further experiments aimed at elucidating the role of the opioid system in cancer cells.

Probing pressure, a highly undervalued unit of measure in periodontal probing: a systematic review on its effect on probing pocket depth.

AIM: To investigate the influence of probing pressure on the probing pocket depth (PPD) in diseased and healthy periodontal tissue conditions through a systematic review. In addition, to facilitate comparison of the study outcomes, an attempt was made to provide a correction factor that compensates for the different probing pressures used. MATERIAL AND METHODS: The MEDLINE-PubMed and Cochrane Central Register of controlled trails (Central) were searched up to June 2008 to indentify appropriate studies. RESULTS: The search yielded 3032 titles and abstracts. In total, five papers fulfilled the eligibility criteria. These studies provided data with probing pressures ranging from 51 to 995 N/cm(2). For the evaluation of the results a distribution was made between diseased and healthy/treated sites. The incremental change in PPD in healthy/treated sites decreased as the pressure increased above 398 N/cm(2). In diseased sites, this phenomenon was already present at pressures above 100 N/cm(2). At healthy/treated sites, a mean increase of PPD of 0.002 mm per increase of 1 N/cm(2) in probing pressure could be calculated whereas at diseased sites this value amounted to 0.004 mm. CONCLUSION: The results show that with increasing probing pressure, the PPD increases. The dimensions of the increase are dependent on the periodontal tissue conditions.

Dynamic filling index: a novel parameter to monitor circulatory filling during minimized extracorporeal bypass.

OBJECTIVE: To evaluate the dynamic filling index, a novel parameter to monitor changes in venous return and drainable volume, in circulatory assisted patients. Minimized extracorporeal bypass systems lack volume buffering capacity, demanding tight control of drainable volume to maintain bypass flow. Therefore, with patients on minimized bypass quantitative assessment of venous drainable volume is crucial. METHODS: In seven patients undergoing coronary artery bypass grafting using minimized extracorporeal bypass we utilized luxation of the heart to induce a reduction in venous return. The speed of the centrifugal pump was transiently and periodically reduced to monitor resultant changes in bypass flow. The dynamic filling index, a measure of drainable volume, was calculated as Deltaflow/Deltaspeed. RESULTS: With luxation, the dynamic filling index was significantly reduced (from 2.4 +/- 0.2 to 2.0 +/- 0.2 ml/rotation, p = 0.001; 95% confidence interval of mean difference: 0.23-0.46 ml/rotation), whereas routinely recorded parameters, like bypass flow, pump inlet and arterial line pressure, did not change significantly. The intra-measurement reproducibility for the dynamic filling index was 0.5 ml/rotation (20% of the mean), suggesting good potential for this parameter to monitor on-pump venous return in patients. CONCLUSION: The dynamic filling index can detect small changes in venous return and drainable volume which remain unrevealed by routinely recorded parameters. This index could be a valuable tool to monitor and control circulatory filling in individual patients supported by minimized extracorporeal bypass.

The in-vivo effect of pyrrolidine dithiocarbamate on hepatic parenchymal microcirculation and oxygenation of the rat liver.

OBJECTIVE: Pyrrolidine dithiocarbamate has been shown to be a potent inducer of haemeoxygenase-1. This study investigated its in-vivo effects on systemic and hepatic microcirculatory perfusion. METHODS: Male Sprague-Dawley rats (n=12) were administered intravenously with pyrrolidine dithiocarbamate (10, 20 and 50 mg/kg body weight) or vehicle (0.2 ml physiological saline) served as control. Systemic and hepatic haemodynamics including arterial oxygen saturation, heart rate, mean arterial blood pressure and portal blood flow were monitored. Microcirculation in skeletal muscle and liver was measured by laser Doppler flowmetry and intravital fluorescence microscopy, whereas hepatic tissue oxyhaemoglobin and cytochrome oxidase CuA redox state, which is an indicative of extracellular and intracellular oxygenation were measured by near infrared spectroscopy. RESULTS: Pyrrolidine dithiocarbamate induced a dose-dependent increase in mean arterial blood pressure and skeletal muscle microcirculation. The hepatic parenchymal microcirculation was significantly improved and an increase in sinusoidal diameter and reduction in RBC velocity were observed. Pyrrolidine dithiocarbamate also showed beneficial effect on hepatic tissue oxygenation showed by an increase in oxyhaemoglobin and cytochrome oxidase CuA redox state as well. CONCLUSION: Pyrrolidine dithiocarbamate improves hepatic parenchymal microcirculation and tissue oxygenation, suggesting that it may be used as a potential agent in pharmacological preconditioning in the liver.