Membrane-associated mucins of the ocular surface: New genes,new protein functions and new biological roles in human and mouse

The mucosal glycocalyx of the ocular surface constitutes the point of interaction between the tear film and the apical epithelial cells. Membrane-associated mucins (MAMs) are the defining molecules of the glycocalyx in all mucosal epithelia. Long recognized for their biophysical properties of hydration, lubrication, anti-adhesion and repulsion, MAMs maintain the wet ocular surface, lubricate the blink, stabilize the tear film and create a physical barrier to the outside world. However, it is increasingly appreciated that MAMs also function as cell surface receptors that transduce information from the outside to the inside of the cell. A number of excellent review articles have provided perspective on the field as it has progressed since 1987, when molecular cloning of the first MAM was reported. The current article provides an update for the ocular surface, placing it into the broad context of findings made in other organ systems, and including new genes, new protein functions and new biological roles. We discuss the epithelial tissue-equivalent with mucosal differentiation, the key model system making these advances possible. In addition, we make the first systematic comparison of MAMs in human and mouse, establishing the basis for using knockout mice for investigations with the complexity of an in vivo system. Lastly, we discuss findings from human genetics/genomics, which are providing clues to new MAM roles previously unimagined. Taken together, this information allows us to generate hypotheses for the next stage of investigation to expand our knowledge of MAM function in intracellular signaling and roles unique to the ocular surface.     

Development of a phantom compatible for MRI and hyperthermia using carrageenan gel—relationship between T1 and T2 values and NaCl concentration

The authors developed a phantom, designated as the CAGN phantom, compatible for MRI and hyperthermia that is useful in the fundamental studies of non-invasive MR thermometry. The ingredients of this phantom are carrageenan, GdCl₃ as a T₁ modifier, agarose as a T₂ modifier, NaCl as a conductivity modifier, NaN₃ as an antiseptic and distilled water. Another phantom that was developed, the CAG phantom, has relaxation times that are adjustable to those of any human tissue. To use this phantom for electromagnetic heating, NaCl was added to change the conductivity of the phantom and clarified the relationship between the conductivity and NaCl concentration. This study examined the relationship between relaxation times and NaCl concentration of the CAGN phantom. The results showed that both T₁ and T₂ values were affected by NaCl and the experimental results led to the empirical formulae expressing the relationship between the relaxation rates (1/T₁, 1/T₂) and the concentrations of GdCl_3, agarose and NaCl. The appropriate concentrations of T₁ and T₂ modifiers were calculated from these empirical formulae when making a specified phantom that has the required relaxation times and NaCl concentration.     

Radial dependence of lineal energy distribution of 290-MeV/u carbon and 500-MeV/u iron ion beams using a wall-less tissue-equivalent proportional counter

Using a wall-less tissue-equivalent proportional counter for a 0.72-μm site in tissue, we measured the radial dependence of the lineal energy distribution, yf(y), of 290-MeV/u carbon ions and 500-MeV/u iron ion beams. The measured yf(y) distributions and the dose-mean of y, y¯D, were compared with calculations performed with the track structure simulation code TRACION and the microdosimetric function of the Particle and Heavy Ion Transport code System (PHITS). The values of the measured y¯D were consistent with calculated results within an error of 2%, but differences in the shape of yf(y) were observed for iron ion irradiation. This result indicates that further improvement of the calculation model for yf(y) distribution in PHITS is needed for the analytical function that describes energy deposition by delta rays, particularly for primary ions having linear energy transfer in excess of a few hundred keV μm⁻¹.     

Development of a phantom compatible for MRI and hyperthermia using carrageenan gel—relationship between dielectric properties and NaCl concentration

A phantom has previously been developed containing carrageenan, agarose and gadolinium chloride (called CAG phantom) for MRI with 1.5?T. T₁ and T₂ relaxation times of this phantom are independently changeable by varying concentrations of relaxation-time modifiers to simulate relaxation times of the various types of human tissues. The CAG phantom has a T₁ value of 202–1904?ms and a T₂ value of 38–423?ms, when the GdCl₃ concentration is varied from 0–140?µmol/kg and the agarose concentration is varied from 0–1.6%. A new phantom has now been developed (called CAGN phantom), made by adding an electric conductive agent, NaCl, to the CAG phantom for use in the areas of MRI and hyperthermia research. Dielectric properties of the CAGN phantom were measured and the results of experiments were expressed by the Cole–Cole equation in the frequency range of 5–130?MHz. The relationship between the conductivity of the CAGN phantom and the concentration of NaCl was expressed by a linear function in the frequency range of 1–130?MHz. The linear function involves a parameter of frequency and, when the frequency is 10?MHz, the conductivity of the CAGN phantom can be changed from 0.27–1.26?Sm^?1 by increasing the NaCl concentration from 0–0.7%. The CAGN phantom developed can be employed in basic experiments for non-invasive temperature measurement using MRI and as a loading phantom for MRI with up to 3?T.     

不同方向60Coγ线照射狗体内平均吸收剂量的差异及计算

本文研究了不同方向⁶⁰Coγ线黑射狗体内平均吸收剂量的差异,用狗的组织当量模体进行了14种不周方向的照射实验,并成功地建立了体内平均吸收剂量D(Gy)与主要参数(d、L、0、Ф,R及X)相互关系的计算公式,其中d及L分别表示照射狗的扁宽及从顶骨到坐骨的长度(cm);θ及Ф令为射线的照射角(度),R是照射源到狗重心的距离(cm)X为狗照射对躯干所在位置空气中当狗体不存在时的平均照射量(c/kg)。实验表明,在其它条件相同时,随照射角θ、Ф击钓变化有显著差异。     

肺肿瘤位置和尺寸对正常肺组织剂量学参数影响的体模研究(英文)

Objective:The aim of the study was to study the effect of the size and location of tumors on the normal lung dose-volume parameters for lung cancer.Methods:Three spheres with diameters of 2, 3 and 4 cm made of tissue-equivalent materials used for simulating tumors were inserted into the upper lobe, middle lobe, lower lobe of the right lung, upper lobe, lower lobe of the left lung of the Rando phantom, respectively.Five-field simplified IMRT(sIMRT) planning were designed.The prescribed dose was 60 Gy/2 Gy/30...