Tca8113舌癌细胞转染骨形成蛋白-Ⅱ型突变受体前后细胞周期相关因子表达的定量分析

目的明确转染骨形成蛋白(BMP)-Ⅱ型突变受体对Tca8113舌癌细胞的作用,以进一步探讨BMPs对口腔上皮恶变的作用机制。方法检测转染BMP-Ⅱ型突变受体的Tca8113舌癌细胞(Tca8113ZR细胞)和Tca8113细胞的细胞周期相关因子Cyclind1、CDK-4、p27和p57的表达。结果转染了BMP-Ⅱ型突变受体后,肿瘤细胞的增殖能力显著减弱。结论BMPs信号在口腔舌癌细胞的恶性变化中起着重要的调控作用,BMPs信号的改变可能导致细胞恶性程度的改变。     

Expression of cytokeratins in human enamel organ

Cytokeratin (CK) is a filament which plays a central role in epithelial tissue and, like the polypeptides of intermediate filaments in general, shows a high degree of tissue specificity. The CK expression patterns of odontogenic epithelia are still poorly described. We studied the distribution of individual CK polypeptides in the human enamel organ at bell stage and in remnants of the dental lamina. Our immunohistochemical study showed that epithelial cells stained for CKs 7, 13, 14 and 19 with slight changes in their pattern during the differentiation phase of odontogenesis. There was negative staining for all other CK polypeptides tested (CKs 8, 10, 16, 17 and 18). Most of the CKs in the enamel organ epithelia did not show differences related to the stage-specific state of differentiation, except for CKs 14 and 19 at the inner enamel epithelium. A strong label for CK 14 was present at the inner dental epithelium at early bell stage, and this was substituted by CK 19 at the late bell stage when the ameloblasts were fully differentiated.     

Therapeutic potential of the

Innate immune mechanisms respond rapidly to bacterial infection. A key cellular component of the innate immune response is the neutrophil, whose cytoplasmic granules contain a variety of antimicrobial proteins and peptides. Among these is the bactericidal/permeability-increasing protein (BPI), a cationic 55 kDa protein whose selective anti-infective action against Gram-negative bacteria is based on its high (nM) affinity for lipopolysaccharide (LPS, or “endotoxin”). Binding of BPI to Gram-negative bacteria results in growth inhibition, serves as an opsonin that enhances phagocytosis of bacteria and inhibits bacteria-induced inflammatory responses by blocking the interaction of LPS with host pro-inflammatory pathways. Expression of BPI appears to be developmentally regulated as human newborns apparently have lower neutrophil BPI levels than adults. BPI expression has also recently been demonstrated in human epithelial cells where it appears to be inducible by endogenous anti-inflammatory lipids (lipoxins). BPI’s potent anti-endotoxic activity against a broad range of Gram-negative bacterial pathogens is manifest in biological fluids and renders it an attractive template for pharmaceutical development. Indeed, rBPI₂₁, an active recombinant protein derived from human BPI, has proven safe in Phase I human trials, shown promise in Phase II trials and has recently completed a Phase III trial for severe meningococcaemia with apparent benefit. Identification and evaluation of additional disease entities characterised by Gram-negative bacteraemia and/or endotoxaemia as possible targets for BPI therapy continues.     

PTEN及Survivin在卵巢上皮性癌中的表达及相关性

目的：研究抑癌基因PTEN及凋亡抑制因子Survivin在卵巢上皮性癌中的表达及相关性。方法：应用免疫组织化学SP法,检测PTEN和Survivin蛋白在20例正常卵巢组织、21例良性上皮性卵巢肿瘤和38例卵巢上皮性癌中的表达。结果：PTEN在卵巢上皮性癌中的表达水平显著低于卵巢良性肿瘤及正常卵巢组织,差异有显著性（P〈0.05）;Survivin与PTEN相反,在卵巢上皮性癌中的表达显著高于良性卵巢肿瘤及正常卵巢组织（P〈0.05）。Survivin与PTEN的表达呈负相关（r=-0.527,P=0.001）。两者的表达均与年龄及病理类型无关（P〉0.05）,而与临床分期、分化程度及是否转移相关（P〈0.05）。结论：PTEN及Survivin蛋白的表达与卵巢上皮性癌的发生、发展有关;两者的联合检测有助于判断卵巢上皮性癌的恶性程度及预后。     

Bestrophin 2: An anion channel associated with neurogenesis in chemosensory systems

The chemosensory neuroepithelia of the vertebrate olfactory system share a life‐long ability to regenerate. Novel neurons proliferate from basal stem cells that continuously replace old or damaged sensory neurons. The sensory neurons of the mouse and rat olfactory system specifically express bestrophin 2, a member of the bestrophin family of calcium‐activated chloride channels. This channel was recently proposed to operate as a transduction channel in olfactory sensory cilia. We raised a polyclonal antibody against bestrophin 2 and characterized the expression pattern of this protein in the mouse main olfactory epithelium, septal organ of Masera, and vomeronasal organ. Comparison with the maturation markers growth‐associated protein 43 and olfactory marker protein revealed that bestrophin 2 was expressed in developing sensory neurons of all chemosensory neuroepithelia, but was restricted to proximal cilia in mature sensory neurons. Our results suggest that bestrophin 2 plays a critical role during differentiation and growth of axons and cilia. In mature olfactory receptor neurons, it appears to support growth and function of sensory cilia. J. Comp. Neurol. 515:585–599, 2009. © 2009 Wiley‐Liss, Inc.     

Estradiol-regulated proline-rich acid protein 1 is repressed by class I histone deacetylase and functions in peri-implantation mouse uterus

Secretory protein proline-rich acid protein 1 (PRAP1) is abundantly expressed in late pregnant uterus. However, regulation and function of PRAP1 in pregnant uterus is still elusive. We firstly reported differential expression of PRAP1 in peri-implantation uteri and its localization in endometrial epithelia. Expression of PRAP1 in uterus was induced by 17β-estradiol and its expression showed a negative correlation with that of class Ihistone deacetylases (HDACs) in isolated endometrial epithelia. PRAP1 was increased by HDACs inhibitor sodium butyrate treatment, while decreased significantly by estrogen receptor inhibitor ICI182,780 via up-regulating class IHDACs. Number of implanted embryos was decreased in mice immunized with pCR3.1-PRAP1 or injected with rabbit anti-PRAP1 antibody. DNA immunization or antibody injection could affect apoptosis and expression of cytokines (IL-4, IFN-γ). In conclusion, both 17β-estradiol and class IHDACs are involved in modulating PRAP1 expression in peri-implantation uteri. Preliminary functional research indicates that neutralizing PRAP1 protein causes reduction of implanted embryos.     

Specific lectin bindings to oval cells and proliferated bile ductules

Histochemical evaluation of lectins was performed to examine the carbohydrate residues of oval cells induced by administration of α-naphthylisothiocyanate (ANIT), 2-acetylaminofluorene (2-AAF) and 3′-methyl-4-dimethylaminoazobenzene (3′-Me-DAB) in comparison with those of normal bile ducts and proliferated bile ductules induced by bile duct ligation. The normal bile ducts showed intense binding of Ricinus communis agglutinin, concanavalin A and wheat germ agglutinin, and weak binding of Ulex europaeus agglutinin I (UEA I). A few cells in the portal bile ducts showed binding of peanut agglutinin (PNA). Two different binding patterns were observed in oval cells and proliferated bile ductules. One group showed increased binding of PNA, while the other showed intense binding of UEA I. In both groups, binding of other lectins was similar to those of the normal bile duct. The first group included oval cells induced by 2-AAF and 3′-Me-DAB, and the second included both oval cells induced by ANIT and proliferated bile ductules induced by ligation. These results suggest that oval cells and proliferated bile ductules have their own specific carbohydrate residues and that oval cells induced by the carcinogens might be a cell population different from those induced by non-carcinogens and proliferated bile ductules by ligation. The authors wish to thank Dr. T. Itoshima and Dr. Y. Okada for their invaluable suggestions, and Mrs. T. Emi for her assistance in preparation of light microscopic examination.     

Forskolin increases apical sodium conductance in cultured toad kidney cells (A6) by stimulating membrane insertion

The role of membrane traffic in the stimulation of apical Na⁺ permeability caused by increases in cytoplasmic cyclic AMP was assessed by measuring the effects of forskolin on transepithelial capacitance (C _T), transepithelial conductance (G _T), and short-circuit current (I _sc) in A6 cultured toad kidney cells. Apical water permeability was probed by recording cell volume changes after reducing the osmolality of the apical bath. We found that forskolin does not increase the osmotic water permeability of the apical membrane of A6 cells, and thus does not stimulate the insertion of water channels. Comparison of the effects of forskolin and insulin on Na⁺ transport demonstrated that both agents produce reversible increases in C _T, G _T and I _sc. G _T and C _T increased proportionally during the rising phase of the insulin response. However, a non-linear relationship between both parameters was recorded when forskolin was given in NaCl Ringer’s solution. The relationship between C _T and G _T became linear after the effects of forskolin on Cl^– conductances were eliminated by substituting Cl^– by an impermeant anion. In contrast, in Cl^–-containing Na⁺-free solutions, the non-linearity became more pronounced. Successive additions of insulin and forskolin caused additive increases in C _T. Because increases in C _T and Na⁺ transport occurred in the absence of stimulation of water permeability and increases of C _T and G _T were directly proportional when Na⁺ was the major permeating ion across the apical membrane, we suggest that the increase in apical Na⁺ permeability in the presence of either forskolin or insulin is due to the insertion of channels residing in intracellular pools. In contrast, the increased Cl^– permeability caused by forskolin may be related to the activation of channels already present in the membrane. Received: 28 October 1998 / Received after revision: 19 January 1999 / Accepted: 11 February 1999     

Abnormalin vitro thymocyte differentiation in a patient with severe combined immunodeficiency-Nezelof's syndrome

Anin vitro coculture model system of CD34+ stem cells and allogenic cultured thymic epithelia fragments was used to evaluate thymocyte differentiation in a 9-month-old child of Amish descent with Nezelof syndrome. Though the patient's stem cells differentiate to acquire normal expression of CD2 and CD7, later steps of maturation were abnormal. There was detectable but reduced expression of CD3 and CD4 phenotypes. CD44+ expression, however, was markedly reduced. CD44 is an adhesion molecule, interacting with the matrix ligands hyaluronan and fibronectin, and is expressed early in thymocyte differentiation and subsequently in mature T cells. It is hypothesized that abnormal expression of CD44 in a variant of severe combined immunodeficiency, Nezelof's syndrome, interferes with normal thymocyte and thymic epithelial interaction, which leads to abnormal thymocyte differentiation.     

Transepithelial dipeptide (glycylsarcosine) transport across epithelial monolayers of human Caco-2 cells is rheogenic

Net transepithelial transport (and cellular accumulation) of the dipeptide glycylsarcosine (Gly-Sar), across the apical membrane of human intestinal Caco-2 epithelia, is driven by a proton gradient (Na⁺-free conditions) and displays saturation kinetics (K_m 17.4±5.1 mM, V_max of 92.8±15.6 nmol.cm^–2.h^–1). Net Gly-Sar transport is associated with the stimulation of an inward short-circuit current (I_sc). This dipeptide-stimulated I_sc is observed in both Na⁺-containing and Na⁺-free conditions, is stimulated by apical acidity, and displays saturation kinetics (in Na⁺-free media at apical pH 6.0, K_m of 13.6±4.5 mM and a V_max of 284.1±39.3 nmol.cm^–2.h^–1). The maximal capacities of Gly-Sar transport and I_sc suggest a dipeptide/proton stoichiometry greater than unity (13).