细胞间黏附分子与胃癌侵袭、转移关系的研究进展

细胞间黏附分子-1(intercellularadhesionmolecule-1,ICAM-1)是体内重要的细胞活性分子,不仅参与了机体免疫过程及炎症反应,而且还通过与其相应配体的结合,介导癌细胞与不同细胞、基质的黏附,最终使癌细胞逃避免疫监视,利于侵袭转移.近年来,对ICAM-1与恶性肿瘤侵袭转移关系的研究已成为研究热点,其在肿瘤侵袭转移中的作用日益受到众多学者的重视.现就其近年的文献从ICAM-1的结构、生物学特征、在胃癌组织中的表达及作用机制等几个方面作一综述.     

Effects of temperature on granulocyte preservation

With the increasing use of granulocyte transfusion it is becoming important to determine if granulocytes can be preserved for a few days. If so, the optimum storage conditions must be identified. We studied the function in vitro of granulocytes collected as they would be for transfusion by continuous-flow centrifuge leukapheresis (CFCL) and filtration leukapheresis (FL). Granulocytes collected by CFCL maintained normal ability to phagocytose and kill bacteria after 48 hr and normal chemotaxis after 24 hr of storage at 20 degrees--24 degrees C. Neither 1 degrees--6 degrees C nor 37 degrees C were as effective in preserving chemotactic response. Agitation of the granulocyte suspension during storage caused reduced bacterial killing and chemotaxis. Granulocytes collected by FL functioned very poorly after 24 hr storage at all temperatures studied. These studies suggest that it may be possible to store CFCL granulocytes at 20 degrees--24 degrees C for 24 hr. FL granulocytes should not be stored at all.     

Bispecific-armed, interferon gamma-primed macrophage-mediated phagocytosis of malignant non-Hodgkin's lymphoma

To show that macrophages can be effectively targeted against malignant B cells, bispecific antibodies (BsAb) were constructed from two antibodies having specificity for the high-affinity Fc receptor for IgG (Fc gamma RI/CD64) and the B-cell differentiation antigens CD19 and CD37. Using a flow cytometry-based assay and confocal imaging, we show that these constructs mediated significant phagocytosis of B lymphocytes by macrophages that could be enhanced with interferon gamma (IFN gamma) and IFN gamma in combination with macrophage colony- stimulating factor. BsAb-dependent phagocytosis was triggered through Fc gamma RI and could be blocked only by using F(ab')2 fragments from the parent molecule or by cross-linking Fc gamma RI. BsAb-dependent phagocytosis was not blocked by antibodies to the other Fc receptors, Fc gamma RII and Fc gamma RIII. Because these antibody constructs bind to an epitope outside the Fc gamma RI ligand binding site, we show that autologous serum, polyclonal IgG, and monomeric IgG1 did not block BsAb- dependent phagocytosis, whereas autologous serum and the IgG fractions blocked parent molecule monoclonal antibody-dependent phagocytosis due to the avid binding of monomeric IgG to Fc gamma RI. Finally, BsAb- mediated phagocytosis was effective against the malignant B cells of patients with mantle cell lymphoma, prolymphocytic leukemia, and chronic lymphocytic leukemia. Based on these studies, we propose that BsAbs may provide an effective means of immunomodulation for patients with B-cell malignancies.     

Toxicity induced by nanoparticles

Nanoparticle research is currently an area of intense scientific interest due to a wide variety of potential applications. Human beings have been exposed to airborne nanosized particles throughout their evolutionary stages, and such exposures have increased dramatically over the last century. Nanoparticle can modify the physicochemical properties of the material as well as create the opportunity for increased uptake and interaction with biological tissues through inhalation, ingestion, and injection. This combination of effects can generate adverse biological effects in living cells. Nanoparticles have proved toxic to human once in the blood stream, nanoparticles, spleen, bone marrow and nervous system can be transported around the body and be taken up by organs tissue and cell cultures, resulting in increased oxidative stress, inflammatory cytokine production and cell death. Unlike larger particles, nanoparticles may be taken up by cell mitochondria and the cell nucleus studies demonstrate the potential for nanoparticles to cause DNA mutation and induce major structural damage to mitochondria, even resulting in cell death. Size is therefore a key factor in determining the potential toxicity of a particle. How these nanoparticles behave inside the body is still a major question that needs to be resolved. There is a responsibility to test and optimize these new nanomaterials early during the development process to eliminate or ameliorate identified toxic characteristics.     

Evaluation of larvicidal activity of the aerial extracts of a medicinal plant,Ammannia baccifera (Linn) against two important species of mosquitoes,Aedes aegypti and Culex quinquefasciatus

ObjectiveTo analyze the larvicidal effect of the aerial extracts of Ammannia baccifera on two important mosquito species, Aedes aegypti and Culex quinquefasciatus.MethodsThe larval mortality of fourth instar larvae of A. aegypti and C. quinquefasciatus after 24h and 48h of treatment were observed separately in control 50, 100, 150, 200, 250, 300, 350, 400, 450 and 500 mg/L concentrations of the aerial extracts (methanol, ethyl acetate, chloroform) of A. baccifera.ResultsBased on the probit analysis, the 24h and 48h aerial methanol extract of A. baccifera LC₅₀value of C. quinquefasciatus was found to be in 164.00 mg/L and 107.00 mg/L and LC₉₀values for C. quinquefasciatus was found be in 310.00 and 261.00 mg/L. The 24h and 48h aerial part of methanol extract of A. baccifera LC₅₀value of A. aegypti was found be in 226.00 mg/L and 186.00 mg/L and LC₉₀values was found be in 476.00 and 309.00 mg/L.ConclusionsThe results indicate that the A. baccifera could be effectively used for the control of mosquito larvae and the possibility of exploiting for the development of commercial larvicides a plant widely occurring in India.     

INFLAMMATORY FIBROID POLYP OF PROXIMAL ILEUM CAUSING RECURRENT INTUSSUSCEPTION

SUMMARY A 64-year-old female presented with episodes of small bowel obstruction. Ultrasound and barium meal showed a polypoidal lesion in the proximal segment of small bowel. The patient underwent emergency surgery because of signs of impending acute intestinal obstruction. Pathology showed characteristic features of an inflammatory fibroid polyp (IFP) which is an important though rare benign cause of small bowel obstruction. We document clinical and pathological aspects of this case.     

Experimental hemarthrosis in the knee of the mature canine

The knee joints of 14 skeletally mature mongrel dogs were subjected to a continuous hemarthrosis. Minimal morphologic changes of the articular cartilage did not occur until after 16 weeks. As early as 4 weeks, biochemical analyses showed a significant decrease in glycosaminoglycans (GAG) that became progressively more severe with time, whereas total collagen was not significantly altered until after 12 and 16 weeks. Bioengineering measurements of the experimental cartilage surfaces showed that the tissue becomes more deformable as well as less resistive to shear than the control at 8 weeks. These differences increased as the duration of hemarthrosis increased.