Keratinocytes play a role in the immunity to Herpes simplex virus type 2 infection

Herpes simplex virus type 2 (HSV-2) infection is the most common cause of genital ulcerative disease in the developed world. Keratinocytes are the primary cells involved in clinical lesions caused by HSV-2. In our study, we intensively examined cytokine expression in the HSV-2-infected keratinocytes. We observed upregulation of a series of cytokines including early-induced antiviral cytokines as interferons α, β (IFN-α, β), tumor necrosis factor α (TNF-α), colony stimulating factors (CSFs) as G-CSF, GM-CSF, interleukin 3 (IL-3), growth factors (EGF, KGF, and IGF-β1), defensins, selectins, leukocyte function-associated antigens (LFAs,) and toll-like receptors (TLR-2, 3, 4, and 9). More importantly, we found that HSV-2-infected keratinocytes stimulated the proliferation of lymphocytes in co-cultivation system. These data suggest that keratinocytes participate in the immune response to HSV-2 infection in two ways. They secrete inflammatory cytokines to resist the HSV-2 infection directly and recruit the immune cells to eliminate the primary infection indirectly and enhance the adaptive immunity to prevent subsequent infections.

Responsiveness and reliability of MRI in knee osteoarthritis: a meta-analysis of published evidence

OBJECTIVE

To summarize literature on the responsiveness and reliability of MRI-based measures of knee osteoarthritis (OA) structural change.

METHODS

A literature search was conducted using articles published up to the time of the search, April 2009. 1338 abstracts obtained with this search were preliminarily screened for relevance and of these, 243 were selected for data extraction. For this analysis we extracted data on reliability and responsiveness for every reported synovial joint tissue as it relates to MRI measurement in knee OA. Reliability was defined by inter- and intra-reader intra-class correlation (ICC), or coefficient of variation, or kappa statistics. Responsiveness was defined as standardized response mean (SRM) - ratio of mean of change over time divided by standard deviation of change. Random-effects models were used to pool data from multiple studies.

RESULTS

The reliability analysis included data from 84 manuscripts. The inter-reader and intra-reader ICC were excellent (range 0.8-0.94) and the inter-reader and intra-reader kappa values for quantitative and semi-quantitative measures were all moderate to excellent (range 0.52-0.88). The lowest value (kappa=0.52) corresponded to semi-quantitative synovial scoring intra-reader reliability and the highest value (ICC=0.94) for semi-quantitative cartilage morphology. The responsiveness analysis included data from 42 manuscripts. The pooled SRM for quantitative measures of cartilage morphometry for the medial tibiofemoral joint was -0.86 (95% confidence intervals (CI) -1.26 to -0.46). The pooled SRM for the semi-quantitative measurement of cartilage morphology for the medial tibiofemoral joint was 0.55 (95% CI 0.47-0.64). For the quantitative analysis, SRMs are negative because the quantitative value, indicating a loss of cartilage, goes down. For the semi-quantitative analysis, SRMs indicating a loss in cartilage are positive (increase in score).

CONCLUSION

MRI has evolved substantially over the last decade and its strengths include the ability to visualize individual tissue pathologies, which can be measured reliably and with good responsiveness using both quantitative and semi-quantitative techniques.

Short-term modulation at synapses between neurons in laminae II-V of the rodent spinal dorsal horn

Unitary excitatory (EPSP) and inhibitory (IPSP) postsynaptic potentials (PSPs) were evoked between neurons in Rexed's laminae (L)II-V of spinal slices from young hamsters (7-24 days old) at 27°C using paired whole cell recordings. Laminar differences in synaptic efficacy were observed: excitatory connections were more secure than inhibitory connections in LII and inhibitory linkages in LII were less reliable than those in LIII-V. A majority of connections displayed paired-pulse facilitation or depression. Depression was observed for both EPSPs and IPSPs, but facilitation was seen almost exclusively for IPSPs. There were no frequency-dependent shifts between facilitation and depression. Synaptic depression was associated with an increased failure rate and decreased PSP half-width for a majority of connections. However, there were no consistent changes in failure rate or PSP time course at facilitating connections. IPSPs evoked at high-failure synapses had consistently smaller amplitude and showed greater facilitation than low-failure connections. Facilitation at inhibitory connections was positively correlated with synaptic jitter and associated with a decrease in latency. At many connections, the paired-pulse ratio varied from trial to trial and depended on the amplitude of the first PSP; dependence was greater for inhibitory synapses than excitatory synapses. Paired-pulse ratios for connections onto neurons with rapidly adapting, "phasic" discharge to depolarizing current injection were significantly greater than for connections onto neurons with tonic discharge properties. These results are evidence of diversity in synaptic transmission between dorsal horn neurons, the nature of which may depend on the types of linkage, laminar location, and intrinsic firing properties of postsynaptic cells.

Glucose metabolism-related protein 1 (GMRP1) regulates pancreatic beta cell proliferation and apoptosis via activation of Akt signalling pathway in rats and mice

AIMS/HYPOTHESIS

We attempted to elucidate the impacts on and possible mechanisms by which glucose metabolism-related protein 1 (GMRP1) affects beta cell survival.

METHODS

Adenovirus-mediated GMRP1 overproduction and siRNA-mediated knockdown were performed in INS-1E cells and rat islets, after which cell proliferation or apoptosis were determined, and phosphorylation of Akt and BCL2-associated agonist of cell death (BAD) investigated. INS-1E cells and rat islets were cultured at 5.6 (low) or 25 mmol/l (high) glucose for 24 or 48 h, and cell proliferation or apoptosis and GMRP1 levels were investigated. INS-1E cells were treated for 24 h with 0, 10, 50 and 100 nmol/l insulin, and GMRP1 levels were determined. After INS-1E cells were transfected with siRNA for 72 h, high glucose-induced cell proliferation and insulin-stimulated Akt phosphorylation were investigated. Glucose-infused rat models were established and beta cell proliferation and mass were evaluated. Levels of GMRP1, and phosphorylation of Akt and BAD were determined in glucose-infused islets. The GMRP1-mediated Akt pathway was also investigated in db/db mice.

RESULTS

Overproduction of GMRP1 promoted beta cell proliferation via increased phosphorylation of Akt. Knockdown of Gmrp1 (also known as Btbd10) reduced phosphorylation of Akt with enhanced beta cell apoptosis. High glucose increased GMRP1 levels and cell proliferation in INS-1E cells and islet cells. Knockdown of Gmrp1 decreased high glucose-induced cell proliferation and insulin-stimulated Akt phosphorylation. Increased GMRP1 levels were involved in the enhancement of beta cell proliferation and mass in glucose-infused islets. Decreased GMRP1 levels may participate in beta cell apoptosis of db/db mice.

CONCLUSIONS/INTERPRETATION

GMRP1 regulates pancreatic beta cell proliferation and apoptosis via activation of Akt signalling pathway.

"Ulm pouch" technique for total gastrectomy. Chinese experiences

AIM

"Ulm pouch" jejunal interposition reconstruction for total gastrectomy was applied in 62 patients in China, and its morphology was observed by virtual endoscopy.

METHODS

The study enrolled 220 patients who underwent total gastrectomy. Among them 62 underwent "Ulm pouch" reconstruction. Patients were 34 men and 28 women, with a mean age of 56 years (range 23-79). Twenty-two patients had underlying diseases, including hypertension and coronary disease, diabetes mellitus, chronic obstructive pulmonary disease (COPD), and malnutrition. An "Ulm pouch" was made from a jejunal segment by using staplers. An esophago-jejuno anastomosis and an end-to-end anastomosis of the distal end of the pouch to the duodenum were also performed by hand sutures or a stapler. The dimensions of the "Ulm pouch" were measured in 10 randomly selected patients, and we observed the pouch's morphology by virtual endoscopy in 13 patients. We performed Roux-Y reconstruction for the remaining patients. Fifty patients received adjuvant chemotherapy and all patients were followed for one to two years postoperatively.

RESULTS

All operations were successful. "Ulm pouch" in size and shape were similarly like actual stomach. Patients regained their appetite within three days of the operation. At one- to two-month postoperative follow-up, patients' nutritional condition had improved and they gained 2-5 kg of body weights. Complications included postoperative cholecystitis, jejuno-duodenal anastomosis leakage and upper gastric bleeding.

CONCLUSION

"Ulm pouch" for total gastrectomy is a safe procedure for alimentary reconstruction. The use of linear and circular staplers simplifies the procedure and reduces operative time. Virtual endoscopy showed that the morphology of the pouch is similar to the native stomach. "Ulm pouch" reconstruction results in a good postoperative quality of life and favorable prognosis.

Characterization of nanoscale mechanical heterogeneity in a metallic glass by dynamic force microscopy

We report nanoscale mechanical heterogeneity of a metallic glass characterized by dynamic force microscopy. Apparent energy dissipation with a variation of ~12%, originating from nonuniform distribution of local viscoelasticity, was observed. The correlation length of the heterogeneity was measured to be ~2.5 nm, consistent with the dimension of shear transformation zones for plastic flow. This study provides the first experimental evidence on the nanoscale viscoelastic heterogeneity in metallic glasses and may fill the gap between atomic models and macroscopic glass properties.

GRP78 promoter polymorphism rs391957 as potential predictor for clinical outcome in gastric and colorectal cancer patients

BACKGROUND

Recently, the analysis of gastric and colorectal tumor specimens determined that 78-kiloDalton glucose-regulated protein (GRP78), an endoplasmic reticulum chaperone, up-regulation serves as an efficient mechanism protecting cells against apoptosis and can confer drug resistance. We tested whether functional polymorphisms within the GRP78 gene are related to clinical outcome in gastric and colorectal cancer (CRC) patients.

PATIENTS AND METHODS

Blood samples of 234 stage II/III CRC patients at the University of Southern California (USC) and formalin-fixed paraffin-embedded tissues of 137 patients with localized gastric adenocarcinoma (GA) at USC and Memorial Sloan-Kettering Cancer Centers were obtained. GRP78 polymorphisms analyzed on germline DNA were correlated with clinical outcome using univariate and multivariate analyses.

RESULTS

GA patients with the combined GRP78 rs391957 C/T and T/T genotype were at higher risk for tumor recurrence and death [hazard ratio (HR) 2.61; P < 0.001 and HR 3.17; P < 0.001, respectively], than those with C/C. These findings were subsequently tested in a CRC cohort where patients with the homozygous T/T genotype were at highest risk for tumor recurrence (HR 2.61; P = 0.015). The results remained significant after adjusting for clinicopathologic determinants.

CONCLUSION

These data provide the first evidence that the GRP78 rs391957 polymorphism can predict clinical outcome in localized GA and locally advanced CRC patients.

Metformin vs thiazolidinediones for treatment of clinical, hormonal and metabolic characteristics of polycystic ovary syndrome: a meta-analysis

OBJECTIVES

Insulin-sensitizing drugs (ISDs) have been advocated for the long-term treatment of polycystic ovary syndrome (PCOS). It is therefore important to compare the efficacy and safety of ISDs such as metformin and thiazolidinediones (TZDs) for the treatment of this syndrome.

METHODS

A meta-analysis to assess the effectiveness and safety of metformin vs TZDs (including pioglitazone and rosiglitazone) in the treatment of PCOS was conducted, using MEDLINE (1966-May 2010) and EMBASE (1988-May 2010) to select randomized controlled trials comparing clinical, hormonal and metabolic results.

RESULTS

Ten trials were included. TZDs were superior to metformin in reducing serum levels of free testosterone (P=0.03) and dehydroepiandrosterone sulfate (DHEA) (P=0.002) after 3 months treatment. Decreases in triglyceride levels were more pronounced with metformin after 6 months (P<0.0001). Decreases in body mass index (BMI) were greater with metformin treatment as assessed at 3 and 6 months (P<0.00001). There were no significant between-group differences concerning improvements in ovulation, pregnancy rate, menstrual patterns or insulin sensitivity, or changes in serum levels of androstenedione, luteinizing hormone, follicle-stimulating hormone, total cholesterol, low-density lipoprotein C or insulin. Metformin caused a significantly higher incidence of side effects such as nausea, diarrhoea and abdominal cramping (P<0.00001). Significant between-study heterogeneity was detected for several variables assessed.

CONCLUSIONS

The findings from this meta-analysis do not indicate that metformin is superior to TZD's for the treatment of PCOS or vice versa. Between studies, heterogeneity was a major confounder. A large scale, well-designed, randomized, controlled trial is needed to further address this issue.

LeERF-1, a novel AP2/ERF family gene within the B3 subcluster, is down-regulated by light signals in Lithospermum erythrorhizon

We previously showed that ethylene might be involved in the process of shikonin biosynthesis regulated by light signals. Here, we cloned a full-length cDNA of LeERF-1, a putative ethylene response factor gene, from Lithospermum erythrorhizon using the RACE (rapid amplification of cDNA ends) method. Phylogenetic analysis revealed that LeERF-1 was classified in the B3 subfamily, together with ERF1 and ORA59 of Arabidopsis. Heterologous expression of LeERF-1 in Arabidopsis showed that LeERF-1:eGFP fusion protein was precisely localised to the nucleus, implying that it might function as a transcription factor. Detailed expression analysis with real-time PCR showed that LeERF-1 was significantly down-regulated by white, blue and red light, although the inhibitory effect of red light was relatively weak compared to other light conditions. Tissue-specific expression analysis also indicated that LeERF-1 was dominantly expressed in the roots, which grow in soil in darkness. These patterns are all consistent with the effects of different light signals on regulating formation of shikonin and its derivatives, indicating that LeERF-1 might be a crucial positive regulator, like other B3 subfamily proteins (such as ORCA3 and ORA59), in regulating biosynthesis of secondary metabolites.