Reduced leucocyte cholesteryl ester transfer protein expression in acute coronary syndromes

OBJECTIVE

Cholesterol ester transfer protein (CETP) plays an important role in HDL cholesterol metabolism. Leucocytes, including monocyte-derived macrophages in the arterial wall synthesize and secrete CETP, but its role in atherosclerosis is unclear. The aim of the current study was to investigate the effect of acute coronary syndromes (ACS) on leucocyte CETP expression.

RESEARCH DESIGN

Peripheral blood mononuclear cells (PBMCs) were freshly isolated from hospitalized ACS patients displaying Braunwald class IIIB unstable angina pectoris (UAP) on admission (t = 0) and at 180 days post inclusion (t = 180) for analysis of CETP expression. In addition, to prove the potential correlation between leucocyte CETP and ACS the effect of acute myocardial infarction on leucocyte CETP expression was studied in CETP transgenic mice.

RESULTS

Upon admission, UAP patients displayed approximately 3-6 fold (P < 0.01) lower CETP mRNA and nearly absent CETP protein expression in PBMCs, as compared to healthy age-/sex-matched controls. Interestingly, CETP mRNA and protein levels were significantly elevated in PBMCs isolated from UAP patients (both stabilized and refractory) at t = 180 as compared to t = 0 (P < 0.01), which was correlated with a reduced inflammatory status after medical treatment. In agreement with the data obtained in UAP patients, markedly down-regulated leucocyte CETP mRNA expression was observed after coronary artery ligation in CETP transgenic mice, which also correlated with increased serum amyloid A levels.

CONCLUSIONS

We are the first to report that episodes of UAP in humans and myocardial infarction in CETP transgenic mice are associated with reduced leucocyte CETP expression. We propose that the impairment in leucocyte CETP production is associated with an enhanced inflammatory status, which could be clinically relevant for the pathogenesis of ACS.

BML-111, a lipoxin receptor agonist, modulates the immune response and reduces the severity of collagen-induced arthritis

OBJECTIVE

Lipoxins (LXs) are endogenous antiinflammatory and pro-resolving eicosanoids generated during various inflammatory conditions. Recent research has revealed the novel immunomodulatory function of LXs. The aim of this study is to investigate whether LXs modulate the pathogenesis of collagen-induced arthritis (CIA), a typical chronic immune-mediated inflammatory disease.

METHODS AND RESULTS

CIA was induced in DBA/1 mice and BML-111, a lipoxin A4 receptor agonist, was administrated. Results indicated that compared with untreated CIA mice, both clinical disease activity scores and histological destruction of joint were significantly reduced in BML-111-treated CIA mice. The dampened joint injury was accompanied by decreased concentrations of serum pro-inflammatory cytokines tumor necrosis factor alpha and interleukin-6 in BML-111-treated CIA mice. In addition, proliferation of isolated spleen cells, as well as circulating levels of antibody to type II collagen, were reduced significantly in BML-111-treated CIA mice.

CONCLUSION

BML-111 attenuated CIA in part by negatively regulating the immune response, which implicates the potential pharmacological value of LXs in the treatment of chronic immune-mediated inflammatory diseases such as RA.

Protein expression levels of excision repair cross-complementation group 1 and xeroderma pigmentosum D correlate with response to platinum-based chemotherapy in the patients with advanced epithelial ovarian cancer

This study was undertaken to examine whether there is an association between excision repair cross-complementation group 1 (ERCC1) and xeroderma pigmentosum D (XPD) protein expression levels and response to platinum-based chemotherapy in epithelial ovarian cancer (EOC). The study cohort consisted of 91 consecutive patients suffering from stage III or IV disease of primary EOC from 1999 to 2004 at the Women's Hospital, School of Medicine, Zhejiang University. There were 36 sensitive cases of serous ovarian cancer, 27 resistant cases of serous ovarian cancer, 15 cases of clear cell cancer, and 13 cases with serous ovarian cancer receiving neoadjuvant chemotherapy. The ovarian tissue microsections were stained by standard immunohistochemical techniques to show ERCC1 and XPD protein expression levels. In resistance group of serous ovarian cancer, ERCC1 and XPD protein expression levels were significantly higher than those of sensitivity group, and after receiving neoadjuvant chemotherapy, they showed 23% and 32% higher than before. Meanwhile, their levels of clear cell cancer group were significantly higher than serous ovarian cancer group's. Upregulation of ERCC1 and XPD protein expression was associated with resistance process to platinum-based chemotherapy in advanced EOC. This study provided evidence that differences of nucleotide excision repair-related genes expression may have an effect on the observed differences in clinical behavior of EOC.

MEMSurgery: an integrated test-bed for vascular surgery

Many surgical procedures require skillful manipulations of blood vessels, especially in conventional invasive or minimally invasive surgical procedures. Current surgical methods do not allow the surgeon to receive any real time feedback of the tissue properties when operating on the vessel. As a result, the unintentional application of excessive force may damage the blood vessel. To minimize such trauma, and to study the interaction of surgical instruments with the vessel structure, we have developed an integrated surgical testbed called MEMSurgery (Microelectromechanical Sensory augmented Surgery). The test-bed integrates four elements: a) force sensors mounted on surgical appliances, b) a feedback control mechanism utilizing the intrinsic mechanical properties of the blood vessel, c) feedback of the force applied on the tissue back to the surgeon through a haptic feedback device, and d) visual feedback by a graphical computer model of the vessel. Finally, we evaluate the performance of MEMSurgery by testing the hypothesis that the combination of haptic feedback, feedback control based on vascular mechanical properties, and real-time visual representation of the vessel will help the surgeon decrease the probability of applying excess force while occluding the blood vessel. To this end, we designed a rodent experimental model to obtain the ideal minimum occlusion force (MOF). After a series of human performance studies, and subsequent comparison to direct application of force on the forceps (without feedback), the results show that the probability of applying reasonable MOF increases from 35.5% to 80%. After a brief training period, the probability increases to 90%.

A novel single-nucleotide polymorphism of the Fcgamma receptor IIIa gene is associated with genetic susceptibility to systemic lupus erythematosus in Chinese populations: a family-based association study

BACKGROUND

Systemic lupus erytematosus (SLE) is characterized by the presence of various autoantibodies and the deposition of immune complexes which are cleared by Fcgamma receptors.

OBJECTIVES

Family-based association analysis was performed to investigate whether the FCGR3A-72S/R and FCGR3A-270T/R polymorphisms are risk factors for SLE in a Chinese population.

METHODS

In total, 119 patients with SLE from 95 nuclear families, aged 14-78 years, who met the American College of Rheumatology 1997 criteria were recruited, as were 316 family members of these patients. We studied two single-nucleotide polymorphisms (SNPs) encoding nonsynonymous substitution in the FCGR3A gene with respect to genetic susceptibility to SLE in a collection of 435 subjects from 95 nuclear families. We performed the genotyping using PCR restriction fragment length polymorphism.

RESULTS

Our results showed that FCGR3A-72R/S have an excess of transmission of the R allele from heterozygous parents to affected offspring (transmission disequilibrium test chi2 = 9.30, P = 0.0032). Univariate (single-marker) family-based association tests demonstrated that a variant allele at SNP rs403016 of the FCGR3A gene was significantly associated with genetic susceptibility to SLE (exon 3, Z = 2.5444, P = 0.01097) in an additive model. The R and S allele frequencies were 39.4% and 60.6%, respectively. The frequencies of FCGR3A 72R/R, R/S and SS genotypes were 9.1%, 60.6% and 30.3%, respectively. However, the FCGR3A-270T/S SNP was not found in this Chinese population.

CONCLUSION

This study suggests a linkage disequilibrium of the FCGR3A-72R/S SNP with SLE, and supports the notion that a novel polymorphism of the FCGR3A-72R/S SNP is associated with genetic susceptibility to SLE in Chinese populations.

Pneumoperitoneum does not influence trocar site implantation during tumor manipulation in a solid tumor model

BACKGROUND

The purpose of this study was to assess tumor implantation at abdominal wound sites following manipulation of a solid abdominal tumor.

METHODS

GW-39 human colon cancer cells were injected into the omentum of golden Syrian hamsters. At 2 weeks, an omental tumor was harvested and animals were randomized to bivalve (A), crush (B), strip (C), or excision (D), with or without pneumoperitoneum. Four 5-mm trocars were inserted into the abdomen, and the tumor was reinserted through the midline, swept through four quadrants, and removed. The incision was closed and pneumoperitoneum at 7 mmHg was maintained for 10 min. Tumor implantation at wound sites was documented at 7 weeks.

RESULTS

Implantation at trocar sites was 53 and 49% with and without pneumoperitoneum in the manipulated groups (A, B, C), respectively (p = 0.993). Implantation at trocar sites was reduced in the control group (D) at 9 and 10% with and without pneumoperitoneum, respectively (p < 0.001).

CONCLUSIONS

Tumor implantation at trocar sites is due to spillage of tumor during manipulation and not to pneumoperitoneum.

Interleukin-7 and suppression of local peritoneal immunity in ovarian carcinoma

OBJECTIVES

To investigate the epithelial ovarian carcinoma (EOC) secretion of interleukin-7 (IL-7).

METHODS

Levels of IL-7 were assayed by enzyme-linked immunoadsorbent assay and IL-7 mRNA, and protein expression in tissues and cell lines were detected by RT-PCR and immunohistochemistry.

RESULTS

The median serum IL-7 level in patients with EOC (32 cases; 32.49 pg/ml) was significantly higher than that of patients with benign tumors (16 cases; 7.59 pg/ml) and healthy women (16 cases; 10.64 pg/ml) (P<0.05). The median peritoneal fluid IL-7 level in patients with EOC (17.39 pg/ml) was slightly higher than that of patients with benign tumors (14.09 pg/ml), but not significantly so (P>0.05). There were positive correlations between the serum and peritoneal fluid IL-7 levels in both ovarian cancer and benign group (P<0.05, both). Only two EOC specimens expressed IL-7 mRNA, and no IL-7 protein positive was found in any specimens.

CONCLUSIONS

Epithelial ovarian carcinoma cells rarely express IL-7, and IL-7 levels are decreased in the ascitic fluid of patients with EOC.

Design of artificial transcription factors to selectively regulate the pro-apoptotic bax gene

The tumor suppressor p53 is the most commonly mutated gene in human cancers. Active p53 is able to stimulate the transcription of a variety of genes including the pro-apoptotic gene bax, as well as p21, a cell cycle regulator. In this study we produced novel zinc finger transcription factors that would selectively increase the expression of bax, but not of other p53 targets. Reporter gene assays in p53-negative Saos-2 cells showed that the novel zinc finger proteins stimulated transcription driven by a minimal bax promoter, but not that driven by a minimal p21 promoter. Moreover, electromobility shift assays demonstrated that the novel transcription factors could bind the bax promoter sequence with high affinity and selectivity. Expression of a five zinc finger protein (5ZFAV) in COS-7 cells resulted in an increase in Bax protein levels, indicating that this novel transcription factor could act on endogenous gene expression. Expression of 5ZFAV also drastically reduced Saos-2 cell survival; this effect could be reversed by the general caspase inhibitor B-D-FMK. These data suggest that 5ZFAV is able to induce apoptosis through increased Bax expression. Further, while expression of 5ZFAV in p53-deficient Saos-2 cells reduced cell survival, there was little effect on U-2 OS cells which have wild-type p53. Thus the selective induction of the pro-apoptotic bax gene may be a valuable adjunct to cancer chemotherapy by diminishing survival of p53-deficient tumor cells.