Anti-CD20 monoclonal antibody rituximab has become an essential component of treatment regimens for B-cell non-Hodgkin lymphoma(NHL).It is routinely incorporated into all phases of conventional treatment of B-cell NHL,but the precise mechanisms of action of rituximab in human remain unknown.This article will clarify the mechanisms of action of rituximab,the incidence and potential mechanisms of resistance.Finally,the novel approaches to modulate the antibody,the tumor cell,and the host immunologic environment to overcome rituximab resistance are discussed.

Objective: To investigate the etiological role of polymorphism IVS1+9C→G in hMSH2 gene in gastric cancers. Methods: A case-control study has been taken on subjects included 72 sporadic gastric, 71 familial gastric cancers and 126 healthy individual controls. Genomic DNA was extracted from peripheral white cell of all subjects. The polymorphism was detected by a PCR-based DHPLC analysis and verified by DNA sequencing. Results: The polymorphism IVS1+9C→G in hMSH2 gene was detected in 33.3%(42/126) Healthy individuals, 40.3%((29/72 ))sporadic gastric and 43.7%(31/71 )familial gastric cancers. Significant difference existed between cancers at young age (

Extracellular matrix plays an important role in maintaining organic structure and function, cellular proliferation and differentiation of normal aorta. Extracellular matrix proteolysis and remodeling of aortic wall resulting from degradation of matrix proteins characterize abdominal aortic aneurysm (AAA). Matrix metalloproteinase and its inhibitor have been implicated as potentially important in this disease, and MMP/TIMP ratios may be the key of AAA formation and development.

AIM:To study phenotypic changes of vascular smooth muscle cells (VSMC) in abdominal aortic aneurysmal (AAA) pathogenesis. METHODS: Tissue samples of human infrarenal aneurysmal and normal aorta(NA), and arterial occlusive diseases(AOD) were evaluated. Monoclonic antibodies of ?-smooth muscle actin(?-SMA), desmin and smooth muscle myosin heavy chain isoforms (SM1, SM2 and SMemb) were used in immunohistochemistry to determine VSMC isoforms. Immunohistochemical results were analyzed with the use of computer-generated image technique. Ultrstructures of VSMC in three tissues above were observed by electron microscope. RESULTS: In control AOD and NA, VSMC in the media were strongly immunostained for ?-SMA, desmin, SM1 and SM2. Immunoreactivity for SMemb was faint or weakly positive in AOD, but negative in NA. In AAA,the balance shifts to SMemb predominance with suppressed ?-SMA, SM1 and SM2 and negative desmin, while in ruptured aneurysmal walls, the expression of SM2 and SMemb were decreased compared with the non-ruptured aneurysmal walls. CONCLUSION:Phenotypic changes of VSMC are concerned with abdominal aortic structure lesion and remodeling, which contributes to AAA formation and development.

Objective To evaluate heparanase inhibitor PI-88 in the inhibition of abdominal aortic aneurysm(AAA) formation. Methods A guinea pig-to-SD rat transplantation model of AAA was established for the observation of therapeutic effects of PI-88 given by continuously administration within 4 weeks after abdominal aortic transplantation. Abdominal aortic diameter, the degree of inflammatory infiltration, microvessel density and the expression of heparanase were determined by immunohistochemistry and Northern blot analysis. Results In contrast to the positive controls, the diameter and inflammatory cell infiltration of graft decreased remarkably after administrating PI-88, and the expression of heparanase and microvessel density decreased accordingly, although still upregulated when compared with negative control. Conclusions PI-88 could prevent formation of AAA by inhibiting heparanase activation.

To explore the pathogenesis and treatment of fever, leukocytosis and thrombocytopenia after endovascular graft exclusion for aortic aneurysm or aortic dissection, 67 patients with infrarenal aortic aneurysm (38) and thoracic aortic dissection (29),were studied,and then received successful endovascular graft exclusion with Dacron covered stent grafts. Sepsis syndrome evaluation (physical examination, analysis of peripheral blood WBC, platelet and urine, chest radiograph, urine and blood cultures) was performed for all patients with postoperative temperature(T) higher than 38 5℃. Fever, leukocytosis and thrombocytopenia in peripheral blood were found in most patients, whose T, WBC and platelet returned to normal between 1 and 2 weeks. Sepsis evaluations failed to identify any source of infection in all patients. These results showed that fever and leukocytosis after endovascular stent graft repair for aortic aneurysm are resulted from systemic inflammatory response syndrome.

Extracellular matrix plays an important role in maintaining organic structure and function, cellular proliferation and differentiation of normal aorta. Extracellular matrix proteolysis and remodeling of aortic wall resulting from degradation of matrix proteins characterize abdominal aortic aneurysm (AAA). Matrix metalloproteinase and its inhibitor have been implicated as potentially important in this disease, and MMP/TIMP ratios may be the key of AAA formation and development. [

Dynamic interactions between cells and underlying extracellular matrices are crucial for development, maintenance of cellular function, and response of tissure to injury and infection. Heparan sulfate proteoglycans(HSPG)are found in extracellular matrices and on the surface of most nuclrarated cells, and play critical roles in cell-cell and cell-matrix signal transduction by binding many molecules, such as growth factors and cytokines. Most of the biological properties of HSPG are conferred by heparan sulfate side chains, which can be degraded by heparanase. Changes of heparanase expression and activity may affect the biological processes above, which enables extravasation of inflammation cells, metastasis and neoangiogenesis of tumor cells invasion.

Objective To evaluate therapeutic effect of transluminal angioplasty and stenting on arteriosclerosis related iliac arterial occlusive disease. Methods This retrospective study included a total of 61 cases (76 limbs) with iliac arterial atherosclerotic occlusive disease, grading as TASC A (n =29),B (n = 16), C (n = 11) and D (n = 5). Percutaneous interventional reconstruction and stent implantation were carried out in our hospital from December 2002 to December 2008. Results In 61 patients (76 lesions) 63 stents were implanted successfully with the success rate of 93% (71/76). The rate of clinical improvement was 100% among the patients who had primary technical success. The ankle-branchial index (ABI) improved from an average of 0. 33 ± 0. 17 before intervention to 0. 72 ± 0. 20 on the day following intervention (P < 0. 05). All cases were followed up between 6 month and 60 month. One year patency rate in all treated lesions was 90% (92% in the TASC A and B, 84% in the TASC C and D).Three year patency rate in all was 75% (80% in the TASC A and B, 63% in the TASC C and D). Five year patency rate was 72%. Conclusion There is a tendency towards utilizing transluminal angioplasty and stenting to treat iliac arterial occlusive disease as a therapy instead of traditional vascular surgery.

Humans ; Hydrocarbons, Brominated ; analysis ; metabolism