The immune privilege of the oral mucosa

Despite high bacterial colonization and frequent allergen contact, acute inflammatory and allergic reactions are rarely seen in the oral mucosa. Therefore we assert that immune tolerance predominates at this site and antigen presenting cells, such as dendritic cells and different T cell subtypes, serve as key players in oral mucosal tolerance induction. In this article we describe the mechanisms that lead to tolerance induced in the oral mucosa and how they differ from tolerance induced in the lower gastrointestinal tract. Furthermore we discuss ways in which novel nonparenteral approaches for immune intervention, such as allergen-specific immunotherapy applied by way of the sublingual route, might be improved to target the tolerogenic properties of the sophisticated oral mucosal immune network.     

Effect of Sulfuric Acid on Swelling Behavior of an Expansive Soil

Soil often becomes contaminated with a variety of chemicals due to leakage of under/aboveground chemical storage tanks, improper discharge of waste, or improper design of waste containment facilities. Contaminated soil water can influence the soil's behavior seriously. Mineralogical alterations play a vital role in such circumstances. This paper describes the impact of varying concentrations of sulfuric acid solutions on the swell behavior of expansive soil containing predominantly montmorillonite. Using the conventional oedometer tests, the swell behavior of soil compacted with water inundated with acid solutions was studied. The soil swell, which is about 2% in water, increases to about 9% with 1N and to 50% with 4N acid solutions. The induced swell in acid solutions is attributable to mineralogical changes. The formation of new minerals and their associated fabric changes are investigated by scanning electron microscopy, X-ray diffraction, and energy dispersive analysis of X-ray on soil samples treated with sulfuric acid. While minerals like gypsum and kornelite are formed in the presence of 1N sulfuric acid, aluminite and chloritoid are formed in the presence of 4N sulfuric acid. These types of alterations are known to occur in iron sulfate minerals and are also found on Mars. The mechanism of mineralogical alterations is presented.     

The spectrum of median craniofacial dysplasia

Given the multiple permutations in craniofacial malformations, classification of median craniofacial dysplasia or midline Tessier no. 0 to 14 clefts has been difficult and disjointed. In this review, the authors present a summary of normal embryology, prior terminology, and their proposed new classification system. Median craniofacial dysplasia has tissue agenesis and holoprosencephaly at one end (the hypoplasias), frontonasal hyperplasia and excessive tissue (the hyperplasias) at the other end, and abnormal splitting or clefting and normal tissue volume (dysraphia) occupying the middle portion of the spectrum. These three distinct subclassifications have different forms of anomalies within their groups.     

Comparative morphology of the skin of Natrix tessellata (family: Colubridae) and Cerastes vipera (family: Viperidae)

We studied beneficial difference of the skin of two snakes. Two snakes were chosen from two different habitats and two families: Colubridae (Natrix tessellata) and Viperidae (Cerastes vipera). The investigations were performed by light and electron microscopy. Histologically, the skin of the studied species show pronounced modifications that correlated with functional demands. The scales in Natrix tessellata overlapped slightly, while in Cerastes vipera they were highly overlapped. SEM shows that scales of Natrix tessellata had bidentate tips while the scales of Cerastes vipera were keeled. Histochemically, in both studied species, melanocytes and collagenous fibres were distributed throughout the dermis. Polysaccharides were highly concentrated in the epidermis and dermis of both species while proteins were highly concentrated only in the epidermis. Transmission electron microscopy (TEM) showed that the skin of both snakes consisted of keratins located in the epidermis. Some lipids and mucus were incorporated into the outer scale surfaces such that lipids were part of the fully keratinised hard layer of the snakes' skins. Lipids are probably responsible for limiting water loss and ion movements across the skin. Melanosomes from epidermal melanocytes were present only in Cerastes vipera. In aggregate, these results indicate that snakeskin may provide an ecological indicator whereby epidermal and integumentary specializations may be ecologically correlated.     

苯肼对红细胞在体衰老过程中微观流变特性的影响

在Brunara等人用苯肼使动物造成急性溶血性贫血的方法基础上,建立一种由急性溶血性贫血后,而诱发家兔幼红细胞增多的非正常生理状态的红细胞在体衰老模型,继而研究新生红细胞从产生到死亡死亡过程,即衰老过程的流变学特性的变化规律。通过对新生红细胞的压积、变形、取向及与之相应的全血的粘度、血沉等指标的连续60多天的监测,发现红细胞在衰老过程中的微观流变学特性确实有明显改变。红细胞在体衰老过程中微观流变特性逐渐变差。     

华西银腊梅挥发油化学成分的研究

用水蒸气蒸馏法提取华西银腊梅挥发油,并用气相色谱-质谱(GC-MS)联用技术对其挥发油的化学成分进行分析,结果共鉴定了其中的39种成分,所鉴定成分含量约占总检出量的87.83%。其化学成分主要为(Z,Z)-9,12-十八碳二烯酸甲酯(9.00%),壬醛(5.83%),二十一烷(5.69%),二十烷(5.08%),辛炔酸(4.50%),2,6,10,15-四甲基十七烷(3.93%),(Z)-6-十八烯酸甲酯(3.65%),3,8-二甲基十一烷(3.52%),1-十六碳炔(3.31%),肉豆蔻酸(2.86%),月桂醛(2.81%),壬酸(2.23%),5,6,7,7α-四氢-4,4,7α三甲基-2(4H)-苯并呋喃酮(2.18%)等。     

Deleterious effects of potassium bromate administration on renal and hepatic tissues of Swiss mice

Potassium bromate (KBrO₃) is widely used as a food additive and is a major water disinfection by-product. The present study reports the side effects of KBrO₃ administration in Swiss mice. Animals were randomly divided into three groups: control, low dose KBrO₃ (100 mg/kg/day) and high dose KBrO₃ (200 mg/kg/day) groups. Administration of KBrO₃ led to decreased white blood corpuscles (WBCs), red blood corpuscles (RBCs) and platelets count in the animals of both the high and the low dose groups. Altered lipid profile represented as low density lipoprotein (LDL), high density lipoprotein (HDL) and cholesterol levels were observed in plasma samples of both KBrO₃ treated groups of mice. Also, an increased plasma level of LDH was detected in both KBrO₃ treated groups. Histological investigations showed impaired renal and hepatic histology that was concomitant with increased plasma Creatinine level in both of KBrO₃-treated groups. Nevertheless, decreased glutathione (GSH) level in both renal and hepatic tissue of mice after KBrO₃ intake was detected. These results show that KBrO₃ has serious damaging effects and therefore, its use should be avoided.     

Context-Specific Mechanisms of Cell Polarity Regulation

Cell polarity is an essential process shared by almost all animal tissues. Moreover, cell polarity enables cells to sense and respond to the cues provided by the neighboring cells and the surrounding microenvironment. These responses play a critical role in regulating key physiological processes, including cell migration, proliferation, differentiation, vesicle trafficking and immune responses. The polarity protein complexes regulating these interactions are highly evolutionarily conserved between vertebrates and invertebrates. Interestingly, these polarity complexes interact with each other and key signaling pathways in a cell-polarity context-dependent manner. However, the exact mechanisms by which these interactions take place are poorly understood. In this review, we will focus on the roles of the key polarity complexes SCRIB, PAR and Crumbs in regulating different forms of cell polarity, including epithelial cell polarity, cell migration, asymmetric cell division and the T-cell immunological synapse assembly and signaling.