Potential role of soluble B7-H3 in liver immunopathogenesis during chronic HBV infection

Immune-mediated mechanisms have been implicated in liver pathogenesis and subsequent progression in hepatitis B virus (HBV) infection. Costimulatory molecules, the important regulators of immune responses, participate in the regulation of liver pathology in HBV infection. However, the role of B7-H3 (CD276, a new member of B7 family) in this process has not been investigated. In this study, we detected abundant soluble B7-H3 (sB7-H3) in the plasma of patients with chronic HBV infections. The increase of the plasma B7-H3 was associated with the progression of liver cirrhosis and accompanied by decreased expression of B7-H3 on hepatocytes. The identification analysis suggests that the plasma B7-H3 might be derived from the membrane-bound B7-H3 on hepatocytes. A functional study showed that immobilized (4Ig) B7-H3Ig fusion protein could inhibit TCR-induced proliferation and IFN-γ secretion of T cells, which could be partially blocked by soluble B7-H3flag fusion protein. These results suggest that the reduced expression of B7-H3 in the livers might temper the inhibition of T-cell responses mediated by B7-H3 expressed on hepatocytes and thus promote the hepatic inflammation and hepatitis progression in the chronic HBV-infected patients.

MiDas: automatic extraction of a common domain of discourse in sleep medicine for multi-center data integration

Clinical studies often use data dictionaries with controlled sets of terms to facilitate data collection, limited interoperability and sharing at a local site. Multi-center retrospective clinical studies require that these data dictionaries, originating from individual participating centers, be harmonized in preparation for the integration of the corresponding clinical research data. Domain ontologies are often used to facilitate multi-center data integration by modeling terms from data dictionaries in a logic-based language, but interoperability among domain ontologies (using automated techniques) is an unresolved issue. Although many upper-level reference ontologies have been proposed to address this challenge, our experience in integrating multi-center sleep medicine data highlights the need for an upper level ontology that models a common set of terms at multiple-levels of abstraction, which is not covered by the existing upper-level ontologies. We introduce a methodology underpinned by a Minimal Domain of Discourse (MiDas) algorithm to automatically extract a minimal common domain of discourse (upper-domain ontology) from an existing domain ontology. Using the Multi-Modality, Multi-Resource Environment for Physiological and Clinical Research (Physio-MIMI) multi-center project in sleep medicine as a use case, we demonstrate the use of MiDas in extracting a minimal domain of discourse for sleep medicine, from Physio-MIMI's Sleep Domain Ontology (SDO). We then extend the resulting domain of discourse with terms from the data dictionary of the Sleep Heart and Health Study (SHHS) to validate MiDas. To illustrate the wider applicability of MiDas, we automatically extract the respective domains of discourse from 6 sample domain ontologies from the National Center for Biomedical Ontologies (NCBO) and the OBO Foundry.

The Caenorhabditis elegans GARP complex contains the conserved Vps51 subunit and is required to maintain lysosomal morphology

Functional characterization of the Golgi-associated retrograde protein (GARP) complex in Caenorhabditis elegans has led to the identification of the conserved metazoan Vps51 subunit. It is found that GARP mutants lead to abnormal lysosomal morphology, GARP subunits interact with a distinct set of Golgi SNAREs, and GARP and GOG complexes show functional overlap.

In yeast the Golgi-associated retrograde protein (GARP) complex is required for tethering of endosome-derived transport vesicles to the late Golgi. It consists of four subunits—Vps51p, Vps52p, Vps53p, and Vps54p—and shares similarities with other multimeric tethering complexes, such as the conserved oligomeric Golgi (COG) and the exocyst complex. Here we report the functional characterization of the GARP complex in the nematode Caenorhabditis elegans. Furthermore, we identified the C. elegans Vps51 subunit, which is conserved in all eukaryotes. GARP mutants are viable but show lysosomal defects. We show that GARP subunits bind specific sets of Golgi SNAREs within the yeast two-hybrid system. This suggests that the C. elegans GARP complex also facilitates tethering as well as SNARE complex assembly at the Golgi. The GARP and COG tethering complexes may have overlapping functions for retrograde endosome-to-Golgi retrieval, since loss of both complexes leads to a synthetic lethal phenotype.

Assessment of cardiac diastolic dysfunction in HIV-infected people without cardiovascular symptoms in China

This study assessed cardiac diastolic dysfunction (DD) in HIV-infected subjects without cardiovascular symptoms in China. Eighty-four HIV-infected patients without cardiovascular symptoms were recruited and compared with 30 HIV-negative control subjects. Cardiac DD was evaluated using echocardiography including tissue Doppler imaging. DD was detected in 47.6% of AIDS patients and 42.8% of HIV-positive patients, which was significantly higher than in HIV-negative controls. After logistic regression analysis, HIV infection was independently correlated with cardiac DD (P < 0.05). Among HIV-positive subjects, logistic regression analysis showed that zidovudine exposure was associated with higher prevalence of DD (P < 0.05). Asymptomatic cardiac DD was observed frequently in HIV-infected subjects. HIV infection itself and zidovudine exposure were correlated with a higher prevalence of cardiac DD.

Irrigation, organic matter addition, and tarping as methods of reducing emissions of methyl iodide from agricultural soil

Methyl iodide (MeI) is increasingly being used as a highly effective alternative to the soil fumigant methyl bromide. Due to its volatile and toxic nature, MeI draws wide attention on its potential atmospheric emission following field fumigation treatment. Using soil columns that make it possible to determine emissions and gas phase distribution of soil fumigants, we studied MeI behavior in two soils differing in organic matter content. Additionally, the effectiveness of surface irrigation and tarping with virtually impermeable film (VIF) was assessed. In the lower organic matter, bare soil (control), emissions of MeI were rapid and high (83% of total). Although the peak emission flux was reduced by irrigation, the total loss was very similar to the control (82%). Tarping with VIF dramatically reduced emissions (0.04% total emissions). In the higher organic matter soil, degradation rate of MeI was increased around 4-fold, leading to a significant reduction in emissions (63% total emissions). The work suggests that surface tarping with VIF would be highly effective as an emissions reduction strategy and would also result in the maintenance of high soil gas concentrations (important for pest control). Ripping of the tarp after two weeks led to an immediate spike release of MeI, but, even so, the flux rate at this time was almost 20 times lower than the peak flux rate in the control. Even with tarp ripping, the total emission loss from the VIF treatment remained low (6%).

1,3-dichloropropene and chloropicrin emissions following simulated drip irrigation to raised beds under plastic films

Using laboratory soil chambers a nonscaled representation of an agricultural raised bed was constructed. For a sandy loam soil, 1,3-dichloropropene (1,3-D) and chloropicrin (CP) were applied at 5 cm depth with an excess of water (simulated drip irrigation). Application was made under both high density polyethylene (HDPE) and virtually impermeable film (VIF) covering the soil bed (the furrow was left uncovered). Soil gas distribution of the fumigants, together with emissions into the headspace above the bed, sidewall and furrow were determined over time. Total emissions from the HDPE treatment were cis 1,3-D 28%, trans 1,3-D 24%, and CP 8%. Due to its lower permeability, the values for VIF were 13%, 7%, and 1.5%, respectively. With HDPE, the majority (86-93%) of the emissions occurred from the bed, while for VIF the majority (92-99%) of the emissions was from the furrow. Compared to a range of literature values for shank injection, the use of drip application appears to offer a benefit in reducing 1,3-D and CP emissions. However, the most meaningful comparison is with our previous data for simulated shank injection where the same soil was covered (completely) with the same plastic films (1). In this comparison, only 1,3-D emissions under HDPE were lower with drip application; 1,3-D emissions under VIF and CP emissions under both films were greater with the drip application.

Craniopharyngiomas in the posterior fossa: a rare subgroup, diagnosis, management and outcomes

OBJECTIVE

Craniopharyngiomas with predominant pars in the posterior fossa are very rare and extremely overlooked. The clinical features, diagnosis and management are different from their sellar/suprasellar counterparts. The purpose of this study was to explore the differing characteristics of posterior fossa craniopharyngiomas.

METHODS

Seven patients with pathologically proven craniopharyngiomas located in the posterior fossa were retrospectively investigated. The clinical data and radiographic findings were presented and analysed.

RESULTS

The primary presentations included headache, diplopia, ataxia and hearing loss. All tumours were located in the retrochiasmatic area, and five of seven displayed a retroinfundibulum growth pattern. The predominant components of the tumours were located in the unilateral cerebellopontine angle (CPA) in six cases, and the bilateral CPA in one case. Total tumour resection was accomplished in five patients. There were transient cranial nerve deficits in three patients, and CSF leakage in one patient. Six patients fully recovered to normal conditions, but one patient had tumour regrowth and had to undergo a secondary resection.

CONCLUSIONS

Posterior fossa craniopharyngiomas are rare and may be considered an independent subgroup of classifications. Tumours arising from the sellar region and extending to the posterior fossa present with their own unusual set of characteristics. These tumours can be radically and safely removed with a combined supra- and intratentorial approach.

Observation of anomalous spin segregation in a trapped Fermi gas

We report the observation of spin segregation, i.e., time-dependent separation of the spin density profiles of two spin states, in a trapped, coherently prepared Fermi gas of 6Li with a magnetically tunable scattering length a12 close to zero. For |a12| approximately = 5 bohr, as the cloud profiles evolve, the measured difference in the densities at the cloud center increases in 200 ms from 0 to approximately = 60% of the initial mean density and changes sign with a12. The data are in disagreement in both amplitude and temporal evolution with a spin-wave theory for a Fermi gas. In contrast, for a Bose gas, an analogous theory has successfully described previous observations of spin segregation. The observed segregated atomic density profiles are far from equilibrium, yet they persist for approximately = 5 s, long compared to the axial trapping period of 6.9 ms. We find the zero crossing in a12=0, where spin segregation ceases, at 527.5+/-0.2 G.

Isolation and partial molecular characterization of heat-stable growth factor from human placenta

A heat-stable growth factor has been purified to homogeneity from human placenta. Purification procedure involved extraction with acidic medium, precipitation using ethanol, DE-52 ion-exchange chromatography, and reversed-phase HPLC. The purified preparation has been named human placental growth factor-1 (HPGF-1), which simulates the proliferation of some cell lines, such as human amniotic cell, mouse marrow tumor cell, and mouse fibroblast cell. The growth factor has an approximate molecular weight of 1 900. It is a glycopeptide which contains a polypeptide chain consisting of 10 amino acid residues with molecular weight of 1 195. The N-terminal residue of the polypeptide chain part is phenylalanine. The molecular weight of non-peptide part is 682. The isoelectric point of the growth factor is pI 6.8.

Combination of CsA, MTX and low-dose, short-course mycophenolate mofetil for GVHD prophylaxis

In an effort to reduce the incidence and severity of acute GVHD (aGVHD), we have developed a new prophylaxis regimen combining cyclosporine and MTX with a short 30-day course of low-dose (500 mg per day) mycophenolate mofetil. This regimen was studied prospectively 100 patients undergoing HLA-matched and 1-antigen-mismatched allogeneic peripheral blood SCT from related donors. The cumulative incidence of aGVHD was 16% (grades II-IV (9.5%) and grades III-IV (1%)). The cumulative incidence of chronic GVHD (cGVHD) was 53% with 28% extensive cGVHD. The cumulative incidence of transplant-related mortality at 100 days and 3 years were 6 and 13%. The estimated probabilities of disease-free survival at 3 years in standard- and high-risk patients were 77 and 30%, respectively (P<0.0001). The estimated probabilities of overall survival at 3 years in standard- and high-risk patients were 77 and 37%, respectively (P<0.0001). These data show a substantial decrease in the risk of developing aGVHD without an increase in relapse or any adverse impact on survival in standard-risk patients.

Torsional ultrasound modality for hard nucleus phacoemulsification cataract extraction

AIM

To evaluate the efficacy and safety of phacoemulsification using torsional modality with different parameter settings for hard nucleus cataract extraction.

DESIGN

A prospective, randomised clinical study.

METHODS

A clinical practice study conducted at the Cataract Service, Zhongshan Ophthalmic Center, Sun-Yat-Sen University, and Guangzhou. One eye each from 198 consecutive patients with cataract density grade IV according to the Emery-Little system classification system, requiring phacoemulsification and intraocular lens implantation, was included. Eyes were randomly assigned to the Linear Torsional combined with Ultrasound power group (Linear Tor+US group, n = 66), 100% Fixed Torsional group (Fixed Tor group, n = 65) and conventional Ultrasound burst group (US group, n = 67). All surgeries were performed by a single experienced surgeon and outcomes evaluated by another surgeon masked to treatment. Intraoperative parameters were Ultrasound Time (UST), Cumulative Dissipated Energy (CDE) and surgical complications. Patients were examined on post-op days 1, 7 and 30. Postoperative outcomes were final best corrected visual acuity (BCVA), average central and incisional corneal thickness and central endothelial cell counts.

RESULTS

The mean UST was lower in the Fixed Tor group than in the US group and in the Lin US+Tor group (p0.01), greater average central corneal and incisional thickness on days 1, 7 (p0.01), and higher average corneal endothelial cell losses on day 7 and 30 days (p

CONCLUSIONS

Torsional combined with ultrasound power or high fixed torsional amplitude can yield more effective hard nucleus phacoemulsification than conventional ultrasound modality.

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MESH Headings

• Aged
• Aged, 80 and over
• Cornea/pathology
• Endothelium, Corneal/pathology
• Female
• Humans
• Lens Nucleus, Crystalline/surgery
• Male
• Middle Aged
• Phacoemulsification/methods
• Prospective Studies
• Tomography, Optical Coherence
• Treatment Outcome
• Ultrasonic Therapy/methods
• Visual Acuity

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Production, characterization and assay application of a purified, baculovirus-expressed, serogroup specific bluetongue virus antigen

The predominant serodiagnostic assay used in many countries to detect bluetongue virus (BTV) infections is a competitive enzyme-linked immunosorbent assay (c-ELISA) which employs two critical reagents: a cell culture-derived BTV antigen and group-specific monoclonal antibody (Mab). Ongoing difficulties have been reported by laboratories in the production and quality control of the native antigen reagent which relies on the presence of adequate molar quantities and appropriate presentation of the major BTV core protein VP7. To address this important issue, a recombinant baculovirus was constructed containing a cDNA copy of genome segment 7 of BTV serotype 11 and used to infect insect cells which, in turn, expressed high levels of theVP7 protein with an estimated molecular mass of 39 kDa. In its purified form, this recombinant protein could be detected by group-specific Mabs designated 3.17.A3 and 8A3B.6 produced against BTV serotypes 1 and 17, respectively, as well as by polyclonal bovine antibodies raised against North American and South African BTV serotypes. No reactivity was observed by Western blot analysis with these two Mabs suggesting that the common antigenic determinants, on the BTV VP7 protein, were mainly conformational. It was interesting to note that the purified recombinant VP7 protein demonstrated a greater degree of reactivity with Mab 8A3B.6 compared to that exhibited with Mab 3.17.A3 when evaluated in an ELISA. Due to its antigenic similarity to the native antigen, the recombinant protein was found to be a suitable replacement for use in a c-ELISA to detect BTV-specific antibodies with the added advantage that it could be consistently produced and was, therefore, amenable to quality control testing for purity, stability and other standards.