Incidence of Complications from Percutaneous Biopsy in Chronic Liver Disease: A Systematic Review and Meta-Analysis.

BACKGROUND: Approaches to liver biopsy have changed over the past decade in patients with chronic liver disease. AIMS: We conducted a systematic review and meta-analysis on the incidence of all complications and technical failure associated with percutaneous liver biopsy. METHODS: We systematically searched PubMed and the Cochrane Library for cohort studies reporting on complications resulting from liver biopsy published between 2010 and 2020. Studies on participants of any age and sex, who underwent any percutaneous biopsy for non-focal liver disease, were selected. All events except mild pain, minor hematoma, vasovagal episodes, fever and fistula were defined as major complications. Random-effect model meta-analyses with and without covariates were performed, to examine the effect of publication year, patient characteristics, outcome collection, and biopsy type on incidences. RESULTS: We identified 30 studies reporting on complications resulting from percutaneous liver biopsy procedures (n = 64,356). Incidence of major complications was 2.44% (95% CI 0.85, 6.75), with mortality at 0.01% (95% CI 0.00, 0.11), hospitalization at 0.65% (95% CI 0.38, 1.11), major bleeding at 0.48% (95% CI 0.22, 1.06), and moderate/severe pain at 0.34% (95% CI 0.08, 1.37). Minor complications at 9.53% (95% CI 3.68, 22.5) were mainly pain at 12.9% (95% CI 5.34, 27.9). Technical failure was high at 0.91% (95% CI 0.27, 3.00). Decreasing patient age significantly increased incidence of hospitalization and major bleeding (P < 0.0001). Hospitalization incidence also significantly increased with disease severity. CONCLUSIONS: Incidence of major (2.4%) and minor (9.5%) complications, and technical failure (0.91%) in percutaneous liver biopsies continues.

Engineering Approaches for Programming Agent-Based IoT Objects Using the Resource Management Architecture.

The Internet of Things (IoT) allows the sharing of information among devices in a network. Hardware evolutions have enabled the employment of cognitive agents on top of such devices, which could help to adopt pro-active and autonomous IoT systems. Agents are autonomous entities from Artificial Intelligence capable of sensing (perceiving) the environment where they are situated. Then, with these captured perceptions, they can reason and act pro-actively. However, some agent approaches are created for a specific domain or application when dealing with embedded systems and hardware interfacing. In addition, the agent architecture can compromise the system's performance because of the number of perceptions that agents can access. This paper presents three engineering approaches for creating IoT Objects using Embedded Multi-agent systems (MAS)-as cognitive systems at the edge of an IoT network-connecting, acting, and sharing information with a re-engineered IoT architecture based on the Sensor as a Service model. These engineering approaches use Belief-Desire-Intention (BDI) agents and the JaCaMo framework. In addition, it is expected to diversify the designers' choice in applying embedded MAS in IoT systems. We also present a case study to validate the whole re-engineered architecture and the approaches. Moreover, some performance tests and comparisons are also presented. The study case shows that each approach is more or less suitable depending on the domain tackled. The performance tests show that the re-engineered IoT architecture is scalable and that there are some trade-offs in adopting one or another approach. The contributions of this paper are an architecture for sharing resources in an IoT network, the use of embedded MAS on top IoT Objects, and three engineering approaches considering agent and artifacts dimensions.

Detection of a new microsporidium Perezia sp. in shrimps Penaeus monodon and P. indicus by histopathology, in situ hybridization and PCR.

Samples of microsporidia-infected shrimps exhibiting clinical signs of cotton shrimp disease were collected from Madagascar, Mozambique, and the Kingdom of Saudi Arabia from 2005 to 2014. The tails of the infected shrimps appeared opaque and whitish; subsequent histological examination revealed the presence of cytoplasmic inclusions and mature spores in tissues of the muscle, hepatopancreas, gills, heart, and lymphoid organ. PCR analysis targeting the small subunit rDNA (SSU rDNA) from infected samples resulted in the amplification of a 1.2 kbp SSU rDNA sequence fragment 94% identical to the corresponding region in the genome of the microsporidian Perezia nelsoni, which infects populations of Penaeus setiferus in the USA. Its SSU rDNA sequence was 100% identical among isolates from Madagascar and Saudi Arabia, indicating that shrimps from the Red Sea and Indian Ocean were infected with the same microsporidium, the novel Perezia sp. A 443 bp fragment of the SSU rDNA sequence was cloned, labeled with digoxigenin and subjected to an in situ hybridization assay with tissue sections of Perezia sp.-infected Penaeus monodon from Madagascar and Mozambique, and P. indicus from Saudi Arabia. The probe hybridized to the mature spores in the hepatopancreas and muscle from which the spores had been obtained for DNA isolation. This assay was specific, showing no reaction to another microsporidium, Enterocytozoon hepatopenaei (EHP), infecting the hepatopancreas of shrimp P. stylirostris cultured in SE Asian countries. We also developed an SSU rDNA-based PCR assay, specific for the novel Perezia sp. This PCR did not react to EHP, nor to genomic DNA of shrimp and other invertebrates.

Development of in situ hybridization and PCR assays for the detection of Enterocytozoon hepatopenaei (EHP), a microsporidian parasite infecting penaeid shrimp.

A microsporidian parasite, Enterocytozoon hepatopenaei (abbreviated as EHP), is an emerging pathogen for penaeid shrimp. EHP has been found in several shrimp farming countries in Asia including Vietnam, Thailand, Malaysia, Indonesia and China, and is reported to be associated with growth retardation in farmed shrimp. We examined the histological features from infected shrimp collected from Vietnam and Brunei, these include the presence of basophilic inclusions in the hepatopancreas tubule epithelial cells, in which EHP is found at various developmental stages, ranging from plasmodia to mature spores. By a PCR targeting the 18S rRNA gene, a 1.1kb 18S rRNA gene fragment of EHP was amplified, and this sequence showed a 100% identity to EHP found in Thailand and China. This fragment was cloned and labeled with digoxigenin-11-dUTP, and in situ hybridized to tissue sections of infected Penaeus vannamei (from Vietnam) and P. stylirostris (Brunei). The results of in situ hybridization were specific, the probe only reacted to the EHP within the cytoplasmic inclusions, not to a Pleistophora-like microsporidium that is associated with cotton shrimp disease. Subsequently, we developed a PCR assay from this 18S rRNA gene region, this PCR is shown to be specific to EHP, did not react to 2 other parasitic pathogens, an amoeba and the cotton shrimp disease microsporidium, nor to genomic DNA of various crustaceans including polychaetes, squids, crabs and krill. EHP was detected, through PCR, in hepatopancreatic tissue, feces and water sampled from infected shrimp tanks, and in some samples of Artemia biomass.

Detection of acute hepatopancreatic necrosis disease (AHPND) in Mexico.

Acute hepatopancreatic necrosis disease (AHPND), which has also been referred to as early mortality syndrome (EMS), initially emerged as a destructive disease of cultured shrimp species in Asia in 2009. The pathogen associated with the disease, Vibrio parahaemolyticus, subsequently spread to the Western Hemisphere and emerged in Mexico in early 2013. The spread to the Western Hemisphere is a major concern to shrimp producers in the region. To date, the only peer-reviewed published method for determining whether mortalities are due to AHPND is through histological examination. A novel PCR detection method was employed to assess samples from Mexico in order to confirm the presence of the pathogen in this country. This manuscript details the detection methods used to confirm the presence of AHPND in Mexico. Both immersion and per os challenge studies were used to expose the Penaeus vannamei to the bacteria in order to induce the disease. Histological analysis confirmed AHPND status following the challenge studies. Also provided are the details of the molecular test by PCR that was used for screening candidate V. parahaemolyticus isolates. A rapid PCR assay for detection of AHPND may help with early detection and help prevent the spread of AHPND to other countries.

"Candidatus Hepatobacter penaei," an intracellular pathogenic enteric bacterium in the hepatopancreas of the marine shrimp Penaeus vannamei (Crustacea: Decapoda).

The bacteria that cause necrotizing hepatopancreatitis in Penaeus vannamei adversely affect penaeid shrimp cultured in the western hemisphere. 16S rRNA and gyrase B gene analyses determined the taxonomic position of these bacteria. The name "Candidatus Hepatobacter penaei" is proposed for these pathogenic bacteria, which are members of the Rickettsiales order.

A histological variant of white spot syndrome virus (WSSV) from the Kingdom of Saudi Arabia.

White spot syndrome virus (WSSV) is highly pathogenic to penaeid shrimp. The major targets of WSSV infection are tissues of ectodermal and mesodermal embryonic origin, predominantly the cuticular epithelium and subcuticular connective tissues. Recently, we discovered a WSSV variant in Penaeus indicus that heavily infects the subcuticular connective tissue, with very slight indications in the cuticular epithelium. The variant was also unusual in that WSSV accumulations were found in the interstitial spaces of both the subcuticular connective tissue and the lymphoid organ. This WSSV variant was confirmed through immunohistochemistry with an anti-WSSV VP28 monoclonal antibody, and also by in situ hybridization with a VP28 DNA probe. By in situ hybridization, shrimp with variant and typical histology were shown a deletion in ORF94, which is characteristic of a new type of WSSV found in Saudi Arabia; apparently, the loss of this ORF is not associated with the variant's reduced capability of infecting the cuticular epithelium cells.

Determination of the infectious nature of the agent of acute hepatopancreatic necrosis syndrome affecting penaeid shrimp.

A new emerging disease in shrimp, first reported in 2009, was initially named early mortality syndrome (EMS). In 2011, a more descriptive name for the acute phase of the disease was proposed as acute hepatopancreatic necrosis syndrome (AHPNS). Affecting both Pacific white shrimp Penaeus vannamei and black tiger shrimp P. monodon, the disease has caused significant losses in Southeast Asian shrimp farms. AHPNS was first classified as idiopathic because no specific causative agent had been identified. However, in early 2013, the Aquaculture Pathology Laboratory at the University of Arizona was able to isolate the causative agent of AHPNS in pure culture. Immersion challenge tests were employed for infectivity studies, which induced 100% mortality with typical AHPNS pathology to experimental shrimp exposed to the pathogenic agent. Subsequent histological analyses showed that AHPNS lesions were experimentally induced in the laboratory and were identical to those found in AHPNS-infected shrimp samples collected from the endemic areas. Bacterial isolation from the experimentally infected shrimp enabled recovery of the same bacterial colony type found in field samples. In 3 separate immersion tests, using the recovered isolate from the AHPNS-positive shrimp, the same AHPNS pathology was reproduced in experimental shrimp with consistent results. Hence, AHPNS has a bacterial etiology and Koch's Postulates have been satisfied in laboratory challenge studies with the isolate, which has been identified as a member of the Vibrio harveyi clade, most closely related to V. parahemolyticus.

Eisosomes mark static sites of endocytosis.

Endocytosis functions to recycle plasma membrane components, to regulate cell-surface expression of signalling receptors and to internalize nutrients in all eukaryotic cells. Internalization of proteins, lipids and other cargo can occur by one of several pathways that have different, but often overlapping, molecular requirements. To mediate endocytosis, effectors assemble transiently underneath the plasma membrane, carry out the mechanics of membrane deformation, cargo selection and vesicle internalization, and then disassemble. The mechanism by which endocytosis initiates at particular locations on the plasma membrane has remained unknown. Sites of endocytosis might be formed randomly, induced by stochastic protein and/or lipid clustering. Alternatively, endocytosis might initiate at specific locations. Here we describe large immobile protein assemblies at the plasma membrane in the yeast Saccharomyces cerevisiae that mark endocytic sites. These structures, termed eisosomes (from the Greek 'eis', meaning into or portal, and 'soma', meaning body), are composed primarily of two cytoplasmic proteins, Pil1 and Lsp1. A plasma membrane protein, Sur7, localizes to eisosomes. These structures colocalize with sites of protein and lipid endocytosis, and their components genetically interact with known endocytic effectors. Loss of Pil1 leads to clustering of eisosome remnants and redirects endocytosis and endocytic effector proteins to these clusters.

New genotypes of white spot syndrome virus (WSSV) and Taura syndrome virus (TSV) from the Kingdom of Saudi Arabia.

White spot syndrome virus (WSSV) and Taura syndrome virus (TSV) are highly pathogenic to penaeid shrimp and have caused significant economic losses in the shrimp culture industry around the world. During 2010 and 2011, both WSSV and TSV were found in Saudi Arabia, where they caused severe mortalities in cultured Indian white shrimp Penaeus indicus. Most outbreaks of shrimp viruses in production facilities can be traced to the importation of infected stocks or commodity shrimp. In an attempt to determine the origins of these viral outbreaks in Saudi Arabia, we performed variable number of tandem repeat (VNTR) analyses for WSSV isolates and a phylogenetic analysis for TSV isolates. From the WSSV genome, the VNTR in open reading frames (ORFs) 125 and 94 were investigated with PCR followed by DNA sequence analysis. The genotypes were categorized as {N125, N94} where N is the number of repeat units in a specific ORF, and the subscript indicates the ORF (i.e. ORFs 125 and 94 in this case). From 15 Saudi Arabia WSSV isolates, we detected 3 genotypes: {6125, 794}, {7125, del94}, and {8125, 1394}. The WSSV genotype of {7125, del94} appears to be a new variant with a 1522 bp deletion encompassing complete coding regions of ORF 94 and ORF 95 and the first 82 bp of ORF 93. For TSV genotyping, we used a phylogenetic analysis based on the amino acid sequence of TSV capsid protein 2 (CP2). We analyzed 8 Saudi Arabian isolates in addition to 36 isolates from other areas: SE Asia, Mexico, Venezuela and Belize. The Saudi Arabian TSV clustered into a new, distinct group. Based on these genotyping analyses, new WSSV and TSV genotypes were found in Saudi Arabia. The data suggest that they have come from wild shrimp Penaeus indicus from the Red Sea that are used for broodstock.

Histopathological characterization and in situ detection of Callinectes sapidus reovirus.

A reovirus (tentatively designated as Callinectes sapidus reovirus, CsRV) was found in the blue crabs C. sapidus collected in Chesapeake Bay in 2005. Histological examination of hepatopancreas and gill from infected crabs revealed eosinophilic to basophilic, cytoplasmic, inclusions in hemocytes and in cells of connective tissue. A cDNA library was constructed from total RNA extracted from hemolymph of infected crabs. One clone (designated as CsRV-28) with a 532-bp insert was 75% identical in nucleotide sequence (and 95% similar in translated amino acid sequence) to the quanylytransferase gene of the Scylla serrata reovirus (SsRV). The insert of CsRV-28 was labeled with digoxigenin-11-dUTP and hybridized to sections of hepatopancreas and gill of infected C. sapidus, this probe reacted to hemocytes and cells in the connective tissue. No reaction was seen in any of the tissues prepared from uninfected crabs. Thus, this in situ hybridization procedure can be used to diagnose CsRV.

Ultrastructural and sequence characterization of Penaeus vannamei nodavirus (PvNV) from Belize.

The Penaeus vannamei nodavirus (PvNV), which causes muscle necrosis in Penaeus vannamei from Belize, was identified in 2005. Infected shrimp show clinical signs of white, opaque lesions in the tail muscle. Under transmission electron microscopy, the infected cells exhibit increases in various organelles, including mitochondria, Golgi stacks, and rough endoplasmic reticulum. Cytoplasmic inclusions containing para-crystalline arrays of virions were visualized. The viral particle is spherical in shape and 19 to 27 nm in diameter. A cDNA library was constructed from total RNA extracted from infected shrimp. Through nucleotide sequencing from the cDNA clones and northern blot hybridization, the PvNV genome was shown to consist of 2 segments: RNA1 (3111 bp) and RNA2 (1183 bp). RNA1 contains 2 overlapped open reading frames (ORF A and B), which may encode a RNA-dependent RNA polymerase (RdRp) and a B2 protein, respectively. RNA2 contains a single ORF that may encode the viral capsid protein. Sequence analyses showed the presence of 4 RdRp characteristic motifs and 2 conserved domains (RNA-binding B2 protein and viral coat protein) in the PvNV genome. Phylogenetic analysis based on the translated amino acid sequence of the RdRp reveals that PvNV is a member of the genus Alphanodavirus and closely related to Macrobrachium rosenbergii nodavirus (MrNV). In a study investigating potential PvNV vectors, we monitored the presence of PvNV by RT-PCR in seabird feces and various aquatic organisms collected around a shrimp farm in Belize. PvNV was detected in mosquitofish, seabird feces, barnacles, and zooplankton, suggesting that PvNV can be spread via these carriers.

Patient understanding and experience of non-invasive imaging diagnostic techniques and the liver patient pathway.

BACKGROUND: Clinical and patient-reported outcomes are positively affected when efforts to increase patient understanding of underlying diseases and foster patient participation are part of care pathways. The prevalence of liver diseases is increasing globally, and successful communication of results from liver diagnostic tests will be important for physicians to ensure patient engagement and encourage adherence to lifestyle changes and therapy. Here, we aimed to explore the impact of non-invasive liver tests on patient experience and patient comprehension of liver disease in chronic liver disease diagnostic pathways typically managed with liver biopsies. RESULTS: 101 participants diagnosed with a range of liver disease aetiologies (90 patients, 11 caregivers) underwent a multiparametric magnetic resonance imaging (MRI) test. A subset of 33 participants was subjected to transient elastography (TE) with FibroScan® in addition to multiparametric MRI. MRI results were analysed using LiverMultiScan™. Participants received results on their liver-health status followed by a semi-structured interview to assess the scan procedure experience, comprehension of the results, and experiences of liver disease. A subset of participants (N = 5) was also engaged in the design, execution, and thematic analysis of the interview transcripts of the study. Analysis of semi-structured interviews revealed: (1) Presentation and discussion of the LiverMultiScan visual report by a physician was an effective contributor to better patient experience and increased comprehension of liver disease. (2) Patients demonstrated preference for non-invasive tests over biopsy for management of liver disease. (3) Patients reported positive experiences with the MRI test during the path for liver disease management. CONCLUSIONS: Patients presented with visual reports of liver test results developed increased understanding of liver disease care which may have contributed to an overall more positive experience. Patients reported that clinical information obtained through non-invasive methods and transmitted through visual reports contributed to clarity, understanding and overall increased satisfaction. We conclude that a shift toward non-invasive testing and visual reporting of clinical information (e.g. picture of liver with visual scale) when possible are likely to contribute to improved physician engagement with patients and lead to better outcomes in the management of chronic liver diseases. Evidence suggests that patient experience and understanding can affect several aspects of clinical care and patient well-being. In this study, 101 patients and patient caregivers affected by liver diseases were recruited to determine how patient experiences of liver disease were affected with the introduction of non-invasive evaluation of the liver with an MRI or ultrasound-based elastography. All 101 participants received an MRI followed by a LiverMultiScan report. 33 participants received an additional FibroScan and report. Following the reports, participants were interviewed and asked to reflect on factors which affected their experience of the procedure and the understanding of their results. We focused on factors related to the layout of the standardised report and the delivery of its results. The interviews were transcribed and analysed for common themes and patterns. Patients and patient advocacy groups were involved in the design and conduct of the study, and analysis of the interview transcripts. Here, we report the perception of patients and patient caregivers on the quality of care and diagnostic experience. Trial registration ClinicalTrials.gov identifier-NCT02877602.

Short-term high-fat diet induces cognitive decline, aggression, and anxiety-like behavior in adult zebrafish.

Obesity is a global health problem with high prevalence and defined by a high body mass index (BMI). Several comorbidities affecting the central nervous system (CNS) are associated with obesity (e.g., neurodegenerative diseases, cognitive deficit, and psychobehavioral disturbs). The zebrafish (Danio rerio) has been considered a suitable model organism to investigate the neurobehavioral features of various human diseases. Here, we verify the impact of a high-fat diet (HFD) on the CNS by specifically assessing the effects of short-term HFD on anxiety-like responses, aggression, social preference, and memory, which are essential behaviors for survival and reproduction. Animals were separated in three experimental groups. The standard diet group (SD) received 7.5 mg/fish of dry food, while HFD groups received 5 mg/fish dry food plus 7.5 (HFD-7.5) or 15 mg/fish (HFD-15) of chicken egg yolk daily. Dietary fat content (w/w) was approximately 6.5%, 16.9%, and 21.1%, respectively. We performed behavioral tests and morphometric analyses after two weeks of HFD. In comparison to SD animals, HFD groups showed typical obesogenic responses with increases in BMI, abdominal length, and body weight. HFD individuals also showed increased aggression and anxiety-like behaviors in the mirror-induced aggression and novel tank diving tests, respectively. Interestingly, HFD did not change the social preference behavior, mean swimming speed or spontaneous activity levels, while the HFD-15 group showed cognitive deficits in the inhibitory avoidance test. Collectively, this "proof-of-concept" study is the first report to characterize the effects of short-term HFD on different behavioral domains of zebrafish with high degree of face validity. Moreover, our data reinforce the growing utility of zebrafish to explore the neurobehavioral basis of obesity, providing clinically translatable data, complementing the existing rodent models and supporting future mechanistic studies.

Rapid Effects of Selection on Brain-wide Activity and Behavior.

Interindividual variation in behavior and brain activity is universal and provides substrates for natural selection [1-9]. Selective pressures shift the expression of behavioral traits at the population level [10, 11], but the accompanying changes of the underlying neural circuitry have rarely been identified [12, 13]. Selection likely acts through the genetic and/or epigenetic underpinnings of neural activity controlling the selected behavior [14]. Endocrine and neuromodulatory systems participate in behavioral diversity and could provide the substrate for evolutionary modifications [15-21]. Here, we examined brain-wide patterns of activity in larval zebrafish selectively bred over two generations for extreme differences in habituation of the acoustic startle response (ASR) [22]. The ASR is an evolutionarily conserved defensive behavior induced by strong acoustic/vibrational stimuli. ASR habituation shows great individual variability that is stable over days and heritable [4, 22]. Selection for high ASR habituation leads to stronger sound-evoked activation of ASR-processing brain areas. In contrast, animals selected for low habituation displayed stronger spontaneous activity in ASR-processing centers. Ablation of dopaminergic tyrosine hydroxylase (TH) neurons decreased ASR sensitivity. Independently selected ASR habituation lineages link the effect of behavioral selection to dopaminergic caudal hypothalamus (HC) neurons [23]. High ASR habituation co-segregated with decreased spontaneous swimming phenotypes, but visual startle responses were unaffected. Furthermore, high- and low-habituation larvae differed in stress responses as adults. Thus, selective pressure over a couple of generations on ASR habituation behavior is able to induce substantial differences in brain activity, carrying along additional behaviors as piggyback traits that might further affect fitness in the wild. VIDEO ABSTRACT.

Case reports of melamine-induced pathology in penaeid shrimp fed adulterated feeds.

Shrimp (Penaeus monodon and P. vannamei) specimens were submitted to the University of Arizona's Aquaculture Pathology Laboratory (UAZAPL) and to the Texas Veterinary Medical Diagnostic Laboratory (TVMDL) in 2007 and 2008 from shrimp-rearing facilities in India and Indonesia for histological testing. These were found to present prominent golden to greenish-brown needle- and plate-like birefringent crystals within multifocal hemocytic granulomas in the antennal gland tubules and peritubular hemal sinuses. Their appearance was very similar to melamine-cyanuric acid-induced crystals previously described from cat and dog kidneys with melamine-associated renal failure (MARF). Significant chronic mortalities were reported from the affected P. vannamei farms in Indonesia, but were not observed in the affected P. monodon facility in India. Shrimp feed was suspected as the source of melamine due to the similarity of the shrimp antennal gland lesions to those present in MARF. 'Normal' and 'suspect' feed samples from the facilities in Indonesia and India were sent to regional laboratories for analysis. Melamine was detected in 2 of 4 feed samples from an affected Indonesian farm. Melamine was not detected in 'normal' feed from the Indian facility, but it was found in 2 'suspect' samples (Feeds A and B) at levels of 183.39 and 112.50 ppm, respectively. A bioassay of Feed A with P. vannamei at UAZAPL confirmed that the melamine-contaminated feed induced prominent granulomas in the antennal gland with the characteristic crystals within 10 d of the first feeding, experimentally confirming the direct relationship of melamine-adulterated feed to the unique pathology observed.

Learning: Complexities of Habituation in Escaping Zebrafish Larvae.

Animals decrease responses to repeating stimuli through habituation. New research has revealed independent tuning of multiple parameters of zebrafish escape behavior during habituation.

Improvement of a PCR method for the detection of necrotizing hepatopancreatitis in shrimp.

Necrotizing hepatopancreatitis (NHP) is considered to be one of the most important bacterial diseases affecting penaeid shrimp culture and is caused by an unclassified Gram-negative, pleomorphic, intracellular Alphaproteobacterium. Due to the enteric nature of the bacteria, PCR is the one non-lethal method available for detection of the pathogen. Over a decade ago, a PCR protocol was developed for detection of NHP, which over the subsequent years was shown to occasionally generate false positive reactions. The University of Arizona Aquaculture Pathology Laboratory has developed a set of primers and PCR cycling parameters that have been tested on a variety of DNA templates, using 2 types of PCR reagent systems, which eliminated the generation of false positive amplicons.

Nucleotide sequence of a Madagascar hepatopancreatic parvovirus (HPV) and comparison of genetic variation among geographic isolates.

A segment of Madagascar hepatopancreatic parvovirus (HPV) genomic sequence (5742 nucleotides) was determined through PCR and direct sequencing. This nucleotide sequence was compared to isolates from Australia, Thailand, Korea, and Tanzania, and the mean distance was determined to be 17%. The Madagascar HPV is closest to the Tanzania isolate (12%), followed by isolates from Korea (15%), Australia (17%) and Thailand (20%). Analysis of the genomic structure revealed that this HPV sequence is comprised of one partial Left open reading frame (ORF) (349 amino acids, aa) and complete Mid (578 aa) and Right (820 aa) ORFs. The amino acid sequences of the 3 ORFs were compared among isolates. The Right ORF was found to have the highest variation with a mean distance of 24%. This was followed by the Left and Mid ORF with distances of 13 and 7%, respectively. A phylogenetic analysis based on the amino acid sequence of the Right ORF divides 7 HPV isolates into 3 well-separated groups: Korea, Thailand, and Australia. The Madagascar HPV clustered with the Korea and Tanzania isolates. In Madagascar, HPV has been detected by histological examination since the 1990s. PCR analysis of a recent (2007) sampling showed a 100% prevalence. HPV was also detected in Mozambique with a 100% prevalence. High (95%) prevalence of HPV was found in wild Penaeus merguinesis collected from New Caledonia. These results indicate that HPV displays a high degree of genetic diversity and is distributed worldwide among populations of penaeid shrimp.

Influence of ethanol on dentin roughness, surface free energy, and interaction between AH Plus and root dentin.

This study aimed to evaluate the influence of different ethanol concentrations on dentin roughness, surface free energy, and contact angle between AH Plus and the root canal dentin. One hundred human maxillary anterior teeth were split longitudinally and 200 dentin specimens were polished to make the surface flatter and smoother. An acrylic bar was positioned between two dentin specimens and impression material was added to create a block, simulating an instrumented root canal space. Specimens were removed from the mold and cleaned in an ultrasonic bath for 10 min. Thereafter, dentin specimens were divided into four groups (n = 50) according to the drying methods used: a) wet: vacuum only, b) paper points: vacuum + absorbent paper points, c) 70% alcohol: 70% alcohol (1 min) + vacuum + absorbent paper points, and d) 100% alcohol: 100% alcohol (1 min) + vacuum + absorbent paper points. A rugosimeter and a goniometer were used to verify the roughness (Ra) and to measure the surface free energy and the contact angle between the AH Plus sealer and the root canal dentin. ANOVA and Tukey tests (α = 0.05) were used for statistical analysis. The 70% and 100% ethanol groups showed significantly decreased roughness as well as increased surface free energy in the root canal dentin when compared to the wet and paper point groups. In addition, ethanol significantly reduced the contact angle between the AH Plus sealer and the root canal dentin. Ethanol solutions (70% and 100%) provide better wettability of AH Plus sealer on dentin surfaces.