Injection techniques to anesthetize the difficult tooth

Failure to achieve anesthesia can be a significant problem in the day-to-day practice of dentistry. The usual strategy following an anesthetic failure is to reinject. Therefore, a good understanding of conventional anesthetic techniques is important. But the practitioner also needs to have a broad armamentarium of injection strategies available for the "difficult-to-anesthetize cases". These strategies include the use of 5 percent lidocaine, intrapulpal injection, periodontal ligament injection and intraosseous injection. This paper will be a brief discussion of those techniques with an emphasis on the intraosseous injection.     

Resting respiratory tract dendritic cells preferentially stimulate T helper cell type 2 (Th2) responses and require obligatory cytokine signals for induction of Th1 immunity

Consistent with their role in host defense, mature dendritic cells (DCs) from central lymphoid organs preferentially prime for T helper cell type 1 (Th1)-polarized immunity. However, the "default" T helper response at mucosal surfaces demonstrates Th2 polarity, which is reflected in the cytokine profiles of activated T cells from mucosal lymph nodes. This study on rat respiratory tract DCs (RTDCs) provides an explanation for this paradox. We demonstrate that freshly isolated RTDCs are functionally immature as defined in vitro, being surface major histocompatibility complex (MHC) II lo, endocytosishi, and mixed lymphocyte reactionlo, and these cells produce mRNA encoding interleukin (IL)-10. After ovalbumin (OVA)-pulsing and adoptive transfer, freshly isolated RTDCs preferentially stimulated Th2-dependent OVA-specific immunoglobulin (Ig)G1 responses, and antigen-stimulated splenocytes from recipient animals produced IL-4 in vitro. However, preculture with granulocyte/macrophage colony stimulating factor increased their in vivo IgG priming capacity by 2-3 logs, inducing production of both Th1- and Th2-dependent IgG subclasses and high levels of IFN-gamma by antigen-stimulated splenocytes. Associated phenotypic changes included upregulation of surface MHC II and B7 expression and IL-12 p35 mRNA, and downregulation of endocytosis, MHC II processing- associated genes, and IL-10 mRNA expression. Full expression of IL-12 p40 required additional signals, such as tumor necrosis factor alpha or CD40 ligand. These results suggest that the observed Th2 polarity of the resting mucosal immune system may be an inherent property of the resident DC population, and furthermore that mobilization of Th1 immunity relies absolutely on the provision of appropriate microenvironmental costimuli.     

Dynamics of glucose-induced insulin release from mouse islets transplanted under the kidney capsule

Mouse pancreatic islet grafts under the kidney capsule of syngeneic hosts were removed and perifused in vitro 1-40 weeks after the transplantation. In comparison with fresh islets, 12- to 40-week-old grafts exhibited an attenuated first phase of glucose-stimulated insulin release. In grafts 1, 12, 28, or 40 weeks old, but not in fresh islets, the mean secretory rate during the initial 10 min of stimulation was significantly lower than that during the subsequent 15 min. When expressed in relation to insulin content, the insulin output in response to 11 mmol/L glucose was no less from grafts than from fresh islets; in grafts 12 or 40 weeks old at 16.7 mmol/L glucose, the fractional output above baseline was significantly diminished during the initial 10 min, but not subsequently. Immediately on switching from basal to stimulatory glucose concentration, there was a transient drop in insulin secretion from the grafts, especially after more than 12 weeks of transplantation and in response to 16.7, as compared with 11, mmol/L glucose. When glucose was switched back from stimulatory to basal concentration, grafts also frequently exhibited a transient increase in the insulin secretory rate. Neither initial drops nor "off responses" were seen in untransplanted islets. The modifications of the secretory dynamics in islet grafts suggest that transplantation influences the balance between the stimulatory and inhibitory influences of glucose on the beta-cell's secretory machinery.     

Wavelet Rasterization

We present a method for analytically calculating an anti‐aliased rasterization of arbitrary polygons or fonts bounded by Bézier curves in 2D as well as oriented triangle meshes in 3D. Our algorithm rasterizes multiple resolutions simultaneously using a hierarchical wavelet representation and is robust to degenerate inputs. We show that using the simplest wavelet, the Haar basis, is equivalent to performing a box‐filter to the rasterized image. Because we evaluate wavelet coefficients through line integrals in 2D, we are able to derive analytic solutions for polygons that have Bézier curve boundaries of any order, and we provide solutions for quadratic and cubic curves. In 3D, we compute the wavelet coefficients through analytic surface integrals over triangle meshes and show how to do so in a computationally efficient manner.     

Contouring Discrete Indicator Functions

We present a method for calculating the boundary of objects from Discrete Indicator Functions that store 2‐material volume fractions with a high degree of accuracy. Although Marching Cubes and its derivatives are effective methods for calculating contours of functions sampled over discrete grids, these methods perform poorly when contouring non‐smooth functions such as Discrete Indicator Functions. In particular, Marching Cubes will generate surfaces that exhibit aliasing and oscillations around the exact surface. We derive a simple solution to remove these problems by using a new function to calculate the positions of vertices along cell edges that is efficient, easy to implement, and does not require any optimization or iteration. Finally, we provide empirical evidence that the error introduced by our contouring method is significantly less than is introduced by Marching Cubes.     

Voltage sensitivity of the osteoclast calcium receptor

We demonstrated previously that osteoclasts possess a divalent cation-sensitive "receptor", the Ca2+ receptor. Activation of the Ca2+ receptor by the surrogate cation Ni2+ was shown to elicit an increase in cytosolic [Ca2+] to a peak value followed by an exponential decline. In the present study we examined the influence of surface membrane voltage on the kinetics of Ca2+ receptor inactivation. The K+ ionophore, valinomycin was applied to intercept the declining phase of the cytosolic [Ca2+] transient elicited by application of between 50 microM- and 5 mM-[Ni2+]. This resulted in a sustained elevation of cytosolic [Ca2+] or even a 'hump' followed by a gradual decline. Such a kinetic alteration persisted in a Ca(2+)-free solution, but was abolished in high extracellular [K+] (105 mM). Thus, we demonstrate for the first time to our knowledge, a modulatory effect of membrane potential on the function of the osteoclast Ca2+ receptor.     

阻截紫外线背光板玻璃

全球领先的特种玻管制造商——德国肖特集团新近开发出两种新型玻璃．用于满足纯平液晶电视显示器(LCD—TFT）的市场需求。这两种新型玻璃8688(Tungsten型)和8271(KOVAR型)是专为纯平液晶电视显示器而开发的。     

Bilinear Accelerated Filter Approximation

Our method approximates exact texture filtering for arbitrary scales and translations of an image while taking into account the performance characteristics of modern GPUs. Our algorithm is fast because it accesses textures with a high degree of spatial locality. Using bilinear samples guarantees that the texels we read are in a regular pattern and that we use a hardware accelerated path. We control the texel weights by manipulating the u, v parameters of each sample and the blend factor between the samples. Our method is similar in quality to Cardinality‐Constrained Texture Filtering [ MS13 ] but runs two times faster.