B7-H1 expression is upregulated in peripheral blood CD14+ monocytes of patients with chronic hepatitis B virus infection, which correlates with higher serum IL-10 levels

Chronicity in hepatitis B virus (HBV) infection is maintained by increased type 2 T-helper cell response, possibly because of increased interleukin-10 (IL-10) productions. B7-H1 can negatively regulate T-cell responses via its receptor, programmed death 1. Ligation of B7-H1 to T-cells can result in the preferential secretion of IL-10. In this study, we investigated whether there was an upregulated expression of B7-H1 in peripheral blood mononuclear cells in patients chronically infected by HBV and further explored the correlation between B7-H1 expression and serum interleukin 2, interferon-gamma, IL-10, HBeAg, alanine aminotransferase (ALT) levels and viral load. Fifty-five patients with chronic HBV infection and 20 healthy controls (HCs) were enrolled in the present study. The results showed that in patients with chronic hepatitis B CD14+ monocytes but not CD3+ and CD19+ cells had a significantly increased expression of B7-H1 compared with HCs, which positively correlates with serum IL-10 levels and the presence of HBeAg and negatively correlates with serum ALT levels. In conclusion, chronic HBV patients harbour an increased B7-H1 expression in CD14+ monocytes compared with controls, which may be responsible for the increased serum IL-10 levels. This might be an important way by which HBV evades an adequate immune response, leading to viral persistence and disease chronicity.

Reduced semen quality in chronic prostatitis patients that induce the release of apoptotic protein Omi/HtrA2 from spermatozoa

The relationship between chronic prostatitis and fertility has been disputed for many years. Several groups have shown infection and autoimmune response against prostate antigens could have a deleterious effect on semen quality and fertility. This study was conducted to test the hypothesis that Omi/HtrA2-induced apoptosis in chronic prostatitis could be a mechanism underlying the observed clinical benefit. The Omi/HtrA2 serine protease is a nuclear-encoded mitochondrial protein, which can be released from mitochondria into the cytosol after apoptosis stimuli, inducing apoptosis in caspase-dependent and independent manners. Forty-one patients diagnosed as suffering from chronic prostatitis were included. Healthy normal individuals were included as controls. Human spermatozoa in the semen were purified by Percoll-gradient technique to separate the seminal plasma and other round cells. Measurements for sperm concentration, motility, morphology, proinflammatory cytokines, Omi/HtrA2 mRNA and protein levels in spermatozoa of chronic protatitis patients, were performed accordingly. Significantly increased levels of proinflammatory cytokines were detected in seminal plasma from these prostatitis patients. Omi/HtrA2 mRNA and protein levels were significantly higher in prostatitis men than in normal men. This study shows that chronic prostatitis patients present important alterations in their semen quality parameters, Omi/HtrA2 mRNA and protein levels of spermatozoa. We speculate that the inflammatory process involved may affect male fertility by release of proapoptotic protein Omi/HtrA2.

Taurine promotes connective tissue growth factor (CTGF) expression in osteoblasts through the ERK signal pathway

Taurine is found in bone tissue, but its function in skeletal tissue is not fully understood. The present study was undertaken to investigate regulation of gene expression of connective tissue growth factor (CTGF), and the roles of mitogen-activated protein kinases (MAPKs) in murine osteoblast MC3T3-E1 cells treated with taurine. Western blot analysis showed taurine stimulated CTGF protein secretion in a dose- and time-dependent manner. Taurine induced activation of extracellular signal-regulated kinase (ERK), but not p38 and c-jun N-terminal Kinase (JNK), in osteoblasts. Furthermore, pretreatment of osteoblasts with the ERK inhibitor PD98059 abolished the taurine-induced CTGF production. These data indicate that taurine induces CTGF secretion in MC3T3-E1 cells mediated by the ERK pathway, and suggest that osteoblasts are direct targets of taurine.

Enhanced immunogenicity and antitumour effects with heterologous prime-boost regime using vaccines based on MG7-Ag mimotope of gastric cancer

MG7-Ag, gastric cancer-associated antigen, has been shown to be immunogenic and has been used as marker molecule for prognosis. In a previous study, we developed an oral DNA vaccine based on MG7-Ag mimotope. However, we failed to detect cellular immune response using the oral MG7-Ag mimotope DNA vaccine. To induce significant T cell response, we developed a recombinant adenovirus vaccine based on MG7-Ag mimotope and evaluated the efficacy and protective effects of heterologous prime-boost immunization protocol with an oral DNA vaccine previously developed. We found that both vaccines were able to elicit a significant humoral response against MG7-Ag, while the highest serum titre MG7 antibody was detected in mice immunized with the heterologous prime-boost immunization protocol. Enzyme-linked immunospot (ELISPOT) assay demonstrated that the heterologous prime-boost immunization strategy was more efficient in inducing T cell response than the homologous prime-boost strategy. In the tumour challenge assay, 2 of 5 mice immunized with the heterologous prime-boost protocol were tumour free, while none of the mice in homologous prime-boost groups or control groups was tumour free. Those tumour-bearing mice in the heterologous prime-boost regime had smaller tumour masses than their counterparts in the homologous prime-boost groups or control groups. Therefore, our study suggests that vaccines against MG7-Ag induce significant immune response against gastric cancer, and that the heterologous prime-boost protocol using different types of vaccines could achieve better protective effect than the homologous prime-boost protocol.

Mycophenolic Acid Upregulates B7-DC Expression on Dendritic Cells, Which Is Associated With Impaired Allostimulatory Capacity of Dendritic Cells

In addition to its effects on lymphocytes, mycophenolic acid (MPA) may inhibit the allostimulatory capacity of dendritic cells (DC) via unknown mechanisms. B7-H1 and B7-DC surface markers on DC negatively regulate T-cell responses via the receptor PD-1. In this study, we sought to investigate whether B7-H1 and B7-DC are responsible for the inhibitory functions of MPA on DC. Mouse bone marrow-derived DC were cultured with recombinant granulocyte macrophage colony-stimulating factor (GM-CSF) and interleukin (IL)-4 in the presence or absence of MPA (0.01 micromol and 0.1 micromol). The DC phenotype was assessed by flow cytometry, their immunostimulatory capacity measured by mixed lymphocyte reaction (MLR), and cytokine production by ELISA. The results showed that MPA not only inhibited the expression of major histocompatibility complex (MHC) class II and costimulatory molecules CD80 and CD86 but upregulated B7-DC expression on mature DC induced by LPS. These findings were associated with a reduced allostimulatory ability and an altered cytokine secretion pattern of DC. Thus, we suggest that MPA upregulates B7-DC expression during DC maturation induced by LPS in vitro, an effect that may be responsible for MPA-mediated inhibitory effects on the allostimulatory capacity of DC.

Taurine transporter is expressed in osteoblasts

Taurine influences bone metabolism and is taken up by cells via a specific transport system, the taurine transporter (TAUT). We report a link between taurine and bone homeostasis by demonstrating transcription and translation of TAUT in bone-forming cells. TAUT was expressed in human primary osteoblasts, the human osteosarcoma osteoblast-like cell line MG63, and the mouse osteoblastic cell line MC3T3-E1. Immunostaining with polyclonal antibodies also demonstrated the presence of TAUT in both human and murine osteoblasts. TAUT mRNA expression and [(3)H]taurine uptake increased during differentiation of MG63 cells in culture. Supplementation of culture medium with taurine enhanced alkaline phosphatase activity and osteocalcin secretion. The regulation and detailed function of taurine and TAUT in bone remain unclear, but our findings suggest a functional role for them in bone homeostasis.

Tissue inhibitor of matrix metalloproteinase-1 suppresses apoptosis of mouse bone marrow stromal cell line MBA-1

We investigated the action of tissue inhibitor of metalloproteinase-1 (TIMP-1) on apoptosis and differentiation of mouse bone marrow stromal cell line MBA-1. TIMP-1 did not affect alkaline phosphatase (ALP) activity, suggesting that it is not involved in osteoblastic differentiation in MBA-1 cells. However, TIMP-1 inhibited MBA-1 apoptosis induced by serum deprivation in a dose-dependent manner. Our study also showed increased Bcl-2 protein expression and decreased Bax protein expression with TIMP-1 treatment. TIMP-1 decreased cytochrome c release and caspase-3 activation in MBA-1 cells. TIMP-1 activated phosphatidylinositol 3-kinase (PI3-kinase) and c-Jun N-terminal kinase (JNK), and the PI3-kinase inhibitor LY294002 or the JNK inhibitor SP600125 abolished its antiapoptotic activity. To investigate whether antiapoptotic action of TIMP-1 was mediated through its inhibition on MMP activities, we constructed mutant TIMP-1 by side-directed mutagenesis, which abolished the inhibitory activity of MMPs by deletion of Cys1 to Ala4. Wild-type TIMP-1 and mutant TIMP-1 expression plasmids were transfected in MBA-1 cells, and results showed that mutant TIMP-1 still protected the induced MBA-1 cell against apoptosis. These data suggest that TIMP-1 antiapoptotic actions are mediated via the PI3-kinase and JNK signaling pathways and independent of TIMP-1 inhibition of MMP activities.

A closed queueing network approach to the analysis of patient flow in health care systems

OBJECTIVES

To model patient flow in health care systems with bed capacity constraints in order to provide a useful decision aid for health service managers.

METHODS

We model the patient flow of health care systems using a closed queueing network framework with the assumption that the system is always full. Key performance measures of the health care system are also derived.

RESULTS

Using parameters taken from a study of a geriatric department in the UK, we show that the model is useful in helping service managers to gain better understanding of the behaviour of the system. In addition, we demonstrate that the model could help improving decision-making by allowing managers to explore different options and evaluate their impacts on performance. Our findings highlight the importance of policy makers taking into account the interactions between different phases of care.

CONCLUSIONS

We have developed a novel approach to modelling the flow of patients through health care systems with constrained bed capacity.

Relationship of circulating MMP-2, MMP-1, and TIMP-1 levels with bone biochemical markers and bone mineral density in postmenopausal Chinese women

INTRODUCTION

Osteoblast-derived matrix metalloproteinase (MMP)-2, MMP-1 and tissue inhibitor of metalloproteinase (TIMP)-1 have been shown to play a role in bone metabolism by degrading the bone matrix.

METHODS

The present study was performed to investigate the relationships between serum MMP-2, MMP-1, or TIMP-1 levels and bone mineral density (BMD), as well as bone biochemical markers, in 297 Chinese postmenopausal women aged 42-80 years.

RESULTS

We found a significant negative weak correlation between MMP-2 and BMD at various skeletal regions. After adjustment for age and BMI, the correlation with BMD at the femoral neck and total hip disappeared. Multiple linear stepwise regression analysis showed that MMP-2 was not a determinant factor for BMD. The significant positive correlations between MMP-2 and bone cross-linked N-telopeptides of type I collagen (NTX), alkaline phosphatase (BAP), and osteocalcin (OC) and were found, and remained significant after adjustment for age and BMI. Moreover, serum MMP-2 concentrations were significantly higher in postmenopausal women with osteoporosis than in age-matched normal controls. There were no significant correlations between MMP-1, TIMP-1 and BMD. There were no significant relationships between MMP-1 and BAP, OC, and NTX. The associations between TIMP-1 and BAP and OC were not specific and constant.

CONCLUSIONS

In conclusion, our results suggest that circulating MMP-2 and markers of bone turnover are correlated, and serum MMP-2 levels may rise with increase in bone turnover.

Renal advances in ultrasound elasticity imaging: measuring the compliance of arteries and kidneys in end-stage renal disease

BACKGROUND/AIMS

Ultrasound elasticity imaging visually represents tissue hardness measurements using high-resolution ultrasound speckle-tracking algorithms. This method has recently been applied in the renal setting to measure arterial compliance in end-stage renal disease (ESRD) and the mechanical properties of transplant kidneys in vivo.

METHODS

Ultrasound radio-frequency signal measurements were made of the brachial artery in 5 ESRD subjects and 5 healthy controls and renal transplant measurements in 2 subjects, 1 with chronic allograft nephropathy (CAN) and 1 with normal graft function.

RESULTS

Maximal brachial artery percent strain measurements for healthy controls were 32.9 +/- 10.2% (mean +/- SD) and for ESRD subjects maximal percent strains were 4.9 +/- 1.8%. Transplant renal cortical strain for the subject with CAN was approximately one third that of the healthy transplant recipient.

CONCLUSION

Ultrasound elasticity imaging offers the potential to noninvasively measure the mechanical properties of structures within the body.

Thermal decomposition of generation-4 polyamidoamine dendrimer films: decomposition catalyzed by dendrimer-encapsulated Pt particles

The thermal decomposition of hydroxyl-terminated generation-4 polyamidoamine dendrimer (G4OH) films deposited on Au surfaces has been compared with decomposition of the same dendrimer encapsulating an approximately 40-atom Pt particle (Pt-G4OH). Infrared absorption reflection spectroscopy studies showed that, when the films were heated in air to various temperatures up to 275 degrees C, the disappearance of the amide vibrational modes occurred at lower temperature for the Pt-G4OH film. Dendrimer decomposition was also investigated by thermogravimetric analysis (TGA) in both air and argon atmospheres. For the G4OH dendrimer, complete decomposition was achieved in air at 500 degrees C, while decomposition of the Pt-G4OH dendrimer was completed at 400 degrees C, leaving only platinum metal behind. In a nonoxidizing argon atmosphere, a greater fraction of the G4OH decomposed below 300 degrees C, but all of the dendrimer fragments were not removed until heating above 550 degrees C. In contrast, Pt-G4OH decomposition in argon was similar to that in air, except that decomposition occurred at temperatures approximately 15 degrees C higher. Thermal decomposition of the dendrimer films on Au surfaces was also studied by temperature programmed desorption (TPD) and X-ray photoelectron spectroscopy (XPS) under ultrahigh vacuum conditions. Heating the G4OH films to 250 degrees C during the TPD experiment induced the desorption of large dendrimer fragments at 55, 72, 84, 97, 127, 146, and 261 amu. For the Pt-G4OH films, mass fragments above 98 amu were not observed at any temperature, but much greater intensities for H(2) desorption were detected compared to that of the G4OH film. XPS studies of the G4OH films demonstrated that significant bond breaking in the dendrimer did not occur until temperatures above 250 degrees C and heating to 450 degrees C caused dissociation of C=O, C-O, and C-N bonds. For the Pt-G4OH dendrimer films, carbon-oxygen and carbon-nitrogen bond scission was observed at room temperature, and further decomposition to atomic species occurred after heating to 450 degrees C. All of these results are consistent with the fact that the Pt particles inside the G4OH dendrimer catalyze thermal decomposition, allowing dendrimer decomposition to occur at lower temperatures. However, the Pt particles also catalyze bond scission within the dendrimer fragments so that decomposition of the dendrimer to gaseous hydrogen is the dominant reaction pathway compared to desorption of the larger dendrimer fragments observed in the absence of Pt particles.

Atrial natriuretic peptide inhibits the actions of FSH and forskolin in meiotic maturation of pig oocytes via different signalling pathways

Atrial natriuretic peptide (ANP) as well as its receptors is found in mammalian ovary and follicular cells and its function in oocyte meiotic maturation has also been reported in Xenopus, hamster and rat. But the results are controversial and the physiological mechanism of ANP on oocyte maturation is not clear, especially the relationship between gonadotrophin and ANP as well as the signal transduction, and these need further study. The present study conducted experiments to examine these questions by using drug treatment and Western blot analysis and focused on pig oocyte meiotic maturation and cumulus expansion in vitro. The results revealed that ANP could inhibited FSH-induced pig oocyte maturation and cumulus expansion and prevent the full phosphorylation of mitogen-activated protein kinase in both oocytes and cumulus cells, and that these inhibitory effects could be mimicked by 8-Br-cyclic guanosine 5'-monophosphate (8-Br-cGMP), but blocked by a protein kinase G (PKG) inhibitor KT5823. Zaprinast, a cGMP-specific phosphodiesterase inhibitor, could enhance the inhibitory effect of ANP on oocyte maturation. A specific analogue of ANP, C-ANP-(4-23), which binds to the natriuretic peptide receptor-C (NPRC), had no effect in either FSH-induced or spontaneous oocyte maturation. Treatment with forskolin, a stimulator of adenylate cyclase, had a biphasic effect; 44 h treatment induced cumulus expansion but inhibited oocyte maturation while 2 h treatment induced maturation of cumulus-enclosed oocytes (CEOs). Both ANP and C-ANP-(4-23) could inhibit the effect of forskolin on CEO maturation, and these inhibitory effects of ANP/C-ANP-(4-23) could be blocked by preincubation with pertussis toxin (PT), consistent with mediation by a Gi protein(s) in the cumulus cells. All these results suggest that ANP is a multifunctional regulator of FSH and forskolin on pig CEO maturation by two signalling mechanisms: one is via a cGMP/PKG pathway, the other is via NPRC receptors in cumulus cells and the activation of the PT-sensitive Gi protein(s).

3-D correlation-based speckle tracking

Widely-used 1-D/2-D speckle tracking techniques in elasticity imaging often experience significant speckle decorrelation in applications involving large elevational motion (i.e., out of plane motion). The problem is more pronounced for cardiac strain rate imaging (SRI) since it is very difficult to confine cardiac motion to a single image plane. Here, we present a 3-D correlation-based speckle tracking algorithm. Conceptually, 3-D speckle tracking is just an extension of 2-D phase-sensitive correlation-based speckle tracking. However, due to its high computational cost, optimization schemes, such as dynamic programming, decimation and two-path processing, are introduced to reduce the computational burden. To evaluate the proposed approach, a 3-D bar phantom under uniaxial compression was simulated for benchmark tests. A more sophisticated 3-D simulation of the left ventricle of the heart was also made to test the applicability of 3-D speckle tracking in cardiac SRI. Results from both simulations clearly demonstrated the feasibility of 3-D correlation-based speckle tracking. With the ability to follow 3-D speckle in 3-D space, 3-D speckle tracking outperforms lower-dimensional speckle tracking by minimizing decorrelation caused by pure elevational translation. In other words, 3-D tracking can push toward solely deformation-limited, decorrelation-optimized speckle tracking. Hardware implementation of the proposed 3-D speckle tracking algorithm using field programmable gate arrays (FPGA) is also discussed.

Salmonella enteritidis clearance and immune responses in chickens following Salmonella vaccination and challenge

Our previous work showed that the cell-mediated immunity (CMI) was enhanced by live Salmonella vaccine (LV). The objective of this study was to evaluate the impact of live and killed Salmonella vaccines on Salmonella enteritidis (SE) clearance and to determine if the clearance was mediated by cell-mediated and/or humoral immunity. Chickens were first immunized at 2 weeks of age followed by a booster dose at 4 weeks, challenged with live SE 2 weeks later (6-week-old) and tested for CMI, antibody response and SE clearance 1-week post SE-challenge (7-week-old). Spleen cell proliferation induced by SE-flagella and Concanavalin A (Con A) were significantly higher and SE shedding was significantly lower in the LV group. The splenic CD3 population was significantly lower and B cells were higher in the control group compared to all the SE-challenged groups (with and without vaccination). Serum antibody to SE-flagella and envelope were significantly higher in the KV group compared to all the other groups. These results suggest that LV protects against SE infection, probably by enhancing the CMI.

Agreements among traditional Chinese medicine practitioners in the diagnosis and treatment of irritable bowel syndrome

BACKGROUND

Traditional Chinese Medicine was frequently used by patients with irritable bowel syndrome.

AIM

To evaluate the agreement on diagnoses and prescription of irritable bowel syndrome among Traditional Chinese Medicine practitioners.

METHODS

Consecutive irritable bowel syndrome patients were interviewed independently by four Traditional Chinese Medicine practitioners. The study was divided into three phases: (i) blinded individual assessment, (ii) discussion to achieve consensus on diagnosis and treatment, (iii) individual assessment based on consensual diagnostic criteria. Patients with other causes of diarrhoea were recruited as controls in phase (iii). Percentage agreement and kappa-value in diagnosis, treatment principle and regime were determined.

RESULTS

Thirty-nine irritable bowel syndrome patients were assessed in phase (i) whereas 65 irritable bowel syndrome patients and 17 non-irritable bowel syndrome controls were studied in phase (iii). The mean agreement rates in diagnosis, treatment principle and regimen were: 57, 58 and 52% for phase (i) and 80, 81 and 80% for phase (iii) (P = 0.002). Accordingly, there was significant improvement in the mean kappa-values in diagnosis (0.11-0.34, P = 0.015) and treatment principle (0.16-0.37, P = 0.002) but not in treatment regime.

CONCLUSIONS

Variations in diagnosis and treatment principles do exist among Traditional Chinese Medicine practitioners. Concordant diagnosis can be reached by mutual understanding and converging opinion among Traditional Chinese Medicine practitioners.

Double-blind, randomized study of the efficacy and safety of oral pharmacokinetically enhanced amoxicillin-clavulanate (2,000/125 milligrams) versus those of amoxicillin-clavulanate (875/125 milligrams), both given twice daily for 7 days, in treatment of bacterial community-acquired pneumonia in adults

This randomized, double-blind, noninferiority trial was designed to demonstrate that pharmacokinetically enhanced amoxicillin-clavulanate (2,000/125 mg) was at least as effective clinically as amoxicillin-clavulanate 875/125 mg, both given twice daily for 7 days, in the treatment of community-acquired pneumonia in adults. In total, 633 clinically and radiologically confirmed community-acquired pneumonia patients (intent-to-treat population) were randomized to receive either oral amoxicillin-clavulanate 2,000/125 mg (n = 322) or oral amoxicillin-clavulanate 875/125 mg (n = 311). At screening, 160 of 633 (25.3%) patients had at least one typical pathogen isolated from expectorated or invasive sputum samples or blood culture (bacteriology intent-to-treat population). Streptococcus pneumoniae (58 of 160, 36.3%), methicillin-susceptible Staphylococcus aureus (34 of 160, 21.3%), and Haemophilus influenzae (33 of 160, 20.6%) were the most common typical causative pathogens isolated in both groups in the bacteriology intent-to-treat population. Clinical success in the clinical per protocol population at test of cure (days 16 to 37), the primary efficacy endpoint, was 90.3% (223 of 247) for amoxicillin-clavulanate 2,000/125 mg and 87.6% (198 of 226) for amoxicillin-clavulanate 875/125 mg (treatment difference, 2.7; 95% confidence interval, -3.0, 8.3). Bacteriological success at test of cure in the bacteriology per protocol population was 86.6% (58 of 67) for amoxicillin-clavulanate 2,000/125 mg and 78.4% (40 of 51) for amoxicillin-clavulanate 875/125 mg (treatment difference, 8.1%; 95% confidence interval, -5.8, 22.1). Both therapies were well tolerated. Amoxicillin-clavulanate 2,000/125 mg twice daily was shown to be as clinically effective as amoxicillin-clavulanate 875/125 mg twice daily for 7 days in the treatment of adult patients with community-acquired pneumonia, without a noted increase in the reported rate of adverse events.