无牙颌颞下颌关节紊乱病患者总义齿修复前后咬合垂直距离改变与髁状突在关节凹内位置的关系

目的:观察咬合垂直距离改变对无牙颌颞下颌关节紊乱病患者两侧颞颌关节髁状突位置的影响。方法:于1994-01/1997-12选择本院口腔修复门诊收治的无牙颌患者中符合颞下颌关节紊乱病诊断标准,同时垂直距离减低的患者48例。实验方案经医院伦理委员会审批,患者均知情同意。将48例无牙颌颞下颌关节紊乱病患者根据垂直距离减低程度的不同分为3组:减低1.8～6.0mm组18例,减低6.1～10.0mm组20例,减低10.1￣14.0mm组10例。通过重新制作一副全口义齿的方法治疗,咬合垂直距离恢复在合适的范围内,3组全口义齿的咬合垂直距离恢复前分别平均为63.4,60.6,54.2mm,恢复后咬合垂直距离分别平均为67.8,68.4,66.4mm,平均抬高4.4,7.8,12.2mm。通过拍摄正中颌位时颞下颌关节薛氏位X射线片测量各组前、后、上关节间隙。结果:垂直距离恢复前,减低1.8～6.0mm组关节后间隙,减低6.1～10.0mm组关节前、后间隙、减低10.1￣14.0mm组关节上、后间隙左右侧相比较,差异有显著性意义(P<0.05)。垂直距离恢复后,3组关节间隙左右侧差异无显著性意义。结论:无牙颌咬合垂直距离减低后可以导致两侧髁状突位置发生不对称改变。     

Combinatorial nanoparticles for cancer diagnosis and therapy

Nanotechnology when engineered together with biotechnology opens a fascinating field with applications in diverse areas such as drug targeting and delivery, medical imaging, biosensing, biomaterials and nanotechnology. Conjugating nanoparticles with biomolecules like QD-herceptin conjugates or QD-aptamer (Apt)-DOX conjugates provides many opportunities for improving many of the current challenges in cancer diagnosis and therapy. This paper reviews combinatorial nanoparticles designed and formulated for cancer imaging and therapy, including inorganic nanoparticles (quantum dots, iron oxide particles, gold nanoparticles and silica and carbon nanoparticles), polymeric nanoparticles (PLGA, PLGA-PEG, PAMAM), liposomes and lipid nanoparticles. These nanoparticles are multifunctional in nature and combine two or more functions like targeting, imaging and therapy. In this review, we have classified these combinatorial targeted nanoparticles into inorganic, polymeric and liposome based nanosystems.     

Effects of smokeless tobacco on chemically transformed hamster oral keratinocytes: role of angiotensin I-converting enzyme

The purpose of this study was to determine whether exposureof chemically transformed golden Syrian hamster oral epidermoidcarcinoma cell (HCPC-1) cultures to smokeless tobacco extract(STE) is associated with a decrease in specific angiotensinI-converting enzyme (ACE) activity and whether this decreasepotentiates bradykinin-induced cell growth. We found that STEinduced a significant concentration- and time-dependent decreasein ACE activity in cultured HCPC-1 cells (P <0.05). STE alonehad no significant effect on cell number. Bradykinin alone induceda slight, but significant, increase in cell number (P <0.05).These effects were signific potentiated by STE (P <0.01).We conclude that STE potentiates bradykinin-induced HCPC-1 cellgrowth, in part by attenuating specific ACE activity in thesecells.     

Participation of CD45, NKR-P1A and ANK61 antigen in rat hepatic NK cell (pit cell)mediated target cell cytotoxicity

AIM Several triggering receptors have been described to be involved in natural killer (NK) cellmediated target cytotoxicity. In these studies, NK cells derived from blood or spleen were used. Pit cells are liver-specific NK cells that possess a higher level of natural cytotoxicity and a different morphology when compared to blood NK cells. The aim of this study was to characterize the role of the NK-triggering molecules NKR-P1A, ANK61 antigen, and CD45 in pit cell-mediated killing of target cells. METHODS 51 Cr-release and DNA fragmentation were used to quantify target cell lysis and apoptosis, respectively. RESULTS Flow cytometric analysis showed that pit cells expressed CD45, NKR-P1A, and ANK61 antigen. Treatment of pit cells with monoclonal antibody ( mAb ) to CD45 ( ANK74 ) not only inhibited CC531s or YAC-1 target lysis but also apoptosis induced by pit cells. The mAbs to NKRP1A (3.2.3) and ANK61 antigen (ANK61) had no effect on pit cell-mediated CC531s or YAC-1 target cytolysis or apoptosis, while they did increase the Fcγ receptor positive (FcγR+) P815 cytolysis and apoptosis. This enhanced cytotoxicity could he inhibited by 3,4-dichloroisocoumarin, an inhibitor of granzymes. CONCLUSION These results indicate that CD45 participates in pit cell-mediated CC531s and YAC-1 target cytolysis and apoptosis. NKR-P1A and ANK61 antigen on pit cells function as activation structures against FcγR+ P815 cells, which was mediated by the perforin/granzyme pathway.     

A method for simultaneous study of the karyotype, morphology, and immunologic phenotype of mitotic cells in hematologic malignancies

A major problem in the cytogenetic analysis of hematologic neoplasms has been an inability to identify the cell from which the chromosomes were obtained. We describe a procedure that allows simultaneous analysis of karyotype and cell cytology in mitotic cells. The method differs from conventional cytogenetic analysis in that after mild hypotonic treatment, the cells are cytocentrifuged onto glass slides. In mitotic cells, this procedure often results in adequate spread of the chromosomes within the intact cell membrane. The cytoplasmic structure also remains intact, so that cytologic preparations are of good quality. Morphologic and immunologic identification of mitotic cells can be done using routine hematologic stains, such as Giemsa or Sudan black B, and various antisera using immunofluorescence techniques. The chromosomes can be simultaneously analyzed either without banding on slides stained with Giemsa or with Q-banding on slides stained with immunofluorescence techniques. Identification of numerical and structural karyotype aberrations thus is possible in morphologically identified cells.     

Acute renal rejection versus acute tubular necrosis in a canine model: MR evaluation

Findings of magnetic resonance (MR) imaging in acute renal rejection and acute tubular necrosis (ATN) were studied in dogs. On T1-weighted images, corticomedullary differentiation was absent in kidneys undergoing acute rejection. The loss of corticomedullary differentiation in these kidneys was secondary to a decrease in the relative signal intensity of the cortex, indicating prolongation of the T1 relaxation time of the cortex. In contrast, corticomedullary differentiation was preserved on T1-weighted images of autotransplanted kidneys and kidneys with ATN. MR imaging findings correlated with changes in water content in these three groups of kidneys. Kidneys undergoing acute rejection showed a marked increase in water content compared with kidneys in the other two groups. No change in fat content was found in any group.