Histochemical examination of cathepsin K,MMP1 and MMP2 in compressed periodontal ligament during orthodontic tooth movement in periostin deficient mice

The purpose of this study was to investigate immunolocalization of collagenolytic enzymes including cathepsin K, matrix metalloproteinase (MMP) 1 and 2 in the compressed periodontal ligament (PDL) during orthodontic tooth movement using a periostin deficient (Pn-/-) mouse model. Twelve-week-old male mice homozygous for the disrupted periostin gene and their wild type (WT) littermates were used in these experiments. The tooth movement was performed according to Waldo’s method, in which elastic bands of 0.5 mm thickness were inserted between the first and second upper molars of mice under anesthesia. At 1 and 3 days after orthodontic force application, mice were fixed with transcardial perfusion of 4 % paraformaldehyde in 0.1 M phosphate buffer (pH 7.4), and the first molars and peripheral alveolar bones were extracted for histochemical analyses. Compared with WT mice, immunolocalization of cathepsin K, MMP1 and MMP2 was significantly decreased at 1 and 3 days after orthodontic tooth movement in the compressed PDL of Pn-/- mice, although MMP1-reactivity and MMP2-reactivity decreased at different amounts. Very little cathepsin K-immunoreactivity was observed in the assessed regions of Pn-/- mice, both before and after orthodontic force application. Furthermore, Pn-/- mice showed a much wider residual PDL than WT mice. Taken together, we concluded that periostin plays an essential role in the function of collagenolytic enzymes like cathepsin K, MMP1 and MMP2 in the compressed PDL after orthodontic force application.     

寒颤对呼吸道复温作用的影响

目的：检测寒颤对呼吸道复温的影响。方法：采用冷水浸泡降温和注射卡肌宁抑制寒颤的方法建立抑制寒颤的低体温犬模型。受试犬吸湿热空气（40．45℃,RH99．9％）及室温空气（19±1℃,RH30％～75％）复温各2h,不同温度空气复温的先后顺序随机安排。复温4h后,加压呼吸湿热空气复温使其恢复自主呼吸,继续呼吸湿热空气复温直至直肠温度（Tr）和食道温度（Te）恢复入水时温度。实验过程中采用间接测热法测定代谢产热量。结果：①抑制寒颤时,吸湿热空气2h可使Tr和Te平均每小时分别增高0．26～0．39℃和0．44—1．11℃,吸室温空气2h可使Tr和re平均每小时分别降低0．24-0．51℃和0．58～0．67℃,Tr和Te的变化与呼吸不同温度空气的先后顺序无关。②有寒颤、自主呼吸湿热空气时,Tr和Te的复温速度分别为2．26～2．33℃／h和1．96～2．38℃／h,较抑制寒颤、呼吸湿热空气时明显加快。③与抑制寒颤、加压呼吸湿热空气时的代谢产热量比较,受试犬恢复寒颤自主呼吸湿热空气时代谢产热量明显增高,使复温速度明显加快。结论：呼吸道复温有助于低体温机体复温。寒颤时机体代谢产热量明显增高,使复温速度明显加快。因此,检测呼吸道复温作用时应抑制寒颤,排除寒颤产热的干扰。     

Involvement of regulatory volume decrease in the migration of nasopharyngeal carcinoma cells

The transwell chamber migration assay and CCD digital camera imaging techniques were used to investigate the relationship between regulatory volume decrease (RVD) and cell migration in nasopharyngeal carcinoma cells (CNE-2Z cells). Both migrated and non-migrated CNE-2Z cells, when swollen by 47% hypotonic solution, exhibited RVD which was inhibited by extracellular application of chloride channel blockers adenosine 5‘-triphosphate (ATP), 5-nitro-2-(3-phenylpropylamino) benzoic acid (NPPB) and tamoxifen. However, RVD rate in migrated CNE-2Z cells was bigger than that of non-migrated cells and the sensitivity of migrated cells to NPPB and tamoxifen was higher than that of nonmigrated cells. ATP, NPPB and tamoxifen also inhibited migration of CNE-2Z cells. The inhibition of migration was positively correlated to the blockage of RVD, with a correlation coefficient (r) = 0.99, suggesting a functional relationship between RVD and cell migration. We conclude that RVD is involved in cell migration and RVD may play an important role in migratory process in CNE-2Z cells.     

Calcitriol and calcium regulate cytokine production and adipocyte-macrophage cross-talk

OBJECTIVE: The objective of this study was to investigate the effects of calcitriol on adipocyte and macrophage cytokine expression as well as release and on adipocyte-macrophage cross-talk in local modulation of inflammation. RESEARCH PROCEDURES AND RESULTS: We investigated calcitriol modulation of the expression of macrophage inhibitory factor (MIF) and macrophage surface-specific protein CD14, two key factors in regulating macrophage function and survival, in differentiated human adipocytes. Calcitriol significantly increased MIF and CD14 expression by 59% and 33%, respectively, while calcium-channel antagonism with nifedipine completely reversed these effects, indicating that calcitriol stimulates MIF and CD14 expression via a calcium-dependent mechanism. Similar results were also found in cultured 3T3-L1 adipocytes; in addition, calcitriol also up-regulated macrophage colony-stimulating factor, macrophage inflammatory protein, interleukin-6 (IL-6) as well as monocyte chemoattractant protein-1 expression in 3T3-L1 adipocytes and stimulated tumor necrosis factor as well as IL-6 expression in RAW 264 macrophages. These effects were blocked by either a calcium-channel antagonist (nifedipine) or a mitochondrial uncoupler (dinitrophenol). Moreover, co-culture of 3T3-L1 adipocytes with RAW 264 macrophages significantly increased the expression and production of multiple inflammatory cytokines in response to calcitriol in both cell types. CONCLUSIONS: These data demonstrate that calcitriol regulates local inflammation via modulating the interaction between adipocytes and macrophages as well as regulating inflammatory cytokine production in each cell type via calcium-dependent and mitochondrial uncoupling-dependent mechanisms. These data provide further mechanistic explanation for our recent observations that suppression of calcitriol by dietary calcium reduces inflammatory cytokine expression and oxidative stress in adipose tissue.     

Preparation of (2S, 3R)-methyl-3-phenylglycidate using whole cells of Pseudomonas putida

Preparation of (2S, 3R)-methyl 3-phenylglycidate via enantioselective hydrolysis of racemic phenylglycidate was carried out using whole cells of Pseudomonas putida. Under optimal conditions (2S, 3R)-methyl-3-phenylglycidate could be got with ee value 99 and 48% chemical yield.     

Production of L(+)-lactic acid with Rhizopus oryzae immobilized in polyurethane foam cubes

Summary Polyurethane foam cubes were employed as carriers to immobilize Rhizopus oryzae for L(+)-lactic acid production. The immobilizing capacity reached 450 g-fresh cell/l-cube. The production rate of L(+)-lactic acid could be threefold increased by using the immobilized R. oryzae. The immobilized cells could be steadily used in repetitive fermentations for more than 10 batches.     

生物素-亲和素偶联探针蛋白芯片检测技术

自行制备一种新型生物素-亲和素偶联探针分子并用于反相蛋白芯片的检测。首先, 将生物素-羊抗鼠IgG与亲和素按照不同比例混合后与鼠IgG蛋白芯片反应, 观察荧光信号的放大情况; 然后以鼠IgG-羊抗鼠IgG体系为研究模式, 对反相蛋白芯片的制备条件进行了考察和优化, 包括荧光分子的非特异性吸附、点样缓冲液的选择以及蛋白的活性等。最后, 采用此偶联探针对反相蛋白芯片进行了检测。结果表明, BSA缓冲液制备的反相蛋白芯片可以防止非特异性吸附, 并有利于保持固定蛋白活性和提高检测限; 另外, 与传统的与生物素-亲和素检测技术相比, 采用生物素-亲和素偶联探针对反相芯片的检测限可以提高4倍左右。表明亲和素-生物素偶联探针成本低、易于合成、并可以与其它的信号放大技术联用进一步提高检测的灵敏度, 有望用于蛋白质芯片的检测。     

Long non‐coding RNA highly up‐regulated in liver cancer promotes epithelial‐to‐mesenchymal transition process in oral squamous cell carcinoma

Oral squamous cell carcinoma (OSCC) is an oral and maxillofacial malignancy that exhibits high incidence worldwide. In diverse human cancers, the long non‐coding RNA (lncRNA) highly up‐regulated in liver cancer (HULC) is aberrantly expressed, but how HULC affects OSCC development and progression has remained mostly unknown. We report that HULC was abnormally up‐regulated in oral cancer tissues and OSCC cell lines, and that suppression of HULC expression in OSCC cells not only inhibited the proliferation, drug tolerance, migration and invasion of the cancer cells, but also increased their apoptosis rate. Notably, in a mouse xenograft model, HULC depletion reduced tumorigenicity and inhibited the epithelial‐to‐mesenchymal transition process. Collectively, our findings reveal a crucial role of the lncRNA HULC in regulating oral cancer carcinogenesis and tumour progression, and thus suggest that HULC could serve as a novel therapeutic target for OSCC.