纤维素酶法提取黄芪多糖

目的研究纤维素酶处理对黄芪多糖提取效果的影响。方法以提取液的总糖和还原糖为考察指标,确定纤维素酶处理工艺。通过不同提取方法提取多糖及扫描电镜分析,探讨纤维素酶处理的效果。结果纤维素酶处理条件的优化为纤维素酶加入量为60U/g生药,酶处理时间90min,温度50℃。与对照工艺相比得率由24.4%提高至30.3%,增加率为24.2%,而多糖的质量分数基本不变。扫描电镜观察表明,纤维素酶明显地分解了黄芪原料中的部分结构多糖,药渣中的网状结构变得十分清晰。结论纤维素酶处理有助于黄芪多糖的提取,能显著提高黄芪多糖的得率。     

坏死股骨头结构特征的微纳观分析

研究股骨头坏死后,不同部位骨小梁的微细结构特征的变化.将内出血严重部位作为出血区,无内出血现象的中心部位作为参照区,分别制备未脱钙参照区、未脱钙出血区、脱钙出血区、脱钙参照区4种样本,在扫描电镜和透射电镜下观测、比较骨小梁的微纳观结构.结果发现,出血区微细结构清晰有序,而参照区则看不到有序的微细结构.股骨头坏死后不同部位不仅显示出不同的宏观特征,其内部微细结构也发生了不同的变化.     

Morphological changes in collagen fiber during development of human fetal parotid and submandibular glands

Parotid and submandibular glands from human fetuses (16, 20, 24, 28, 32 weeks of gestation) were examined under a scanning electron microscope. Changes were found in the arrangement of collagen fibers in the connective tissue surrounding the salivary gland. In particular, several layers around the salivary gland were formed by a collagen network structure. These structures, although in varied arrangements, were recognizable in each stage of fetal growth. They are thought to play the role of a "cushion" against pressure created by accumulation of granules because of the reflex activity of myoepithelial cells during secretion. These structural changes are related to the mechanical performance of granule formation in the salivary gland and secretion during the development of the fetus.     

Neuromuscular adaptations in older males and females with knee osteoarthritis during weight-bearing force control

Background

Females exhibit significantly greater incidence, prevalence, and severity of osteoarthritis (OA) compared to males. Despite known biological, morphological, and functional differences between males and females, there has been little sex-related investigation into sex-specific biomechanical and neuromuscular responses to OA.

Tualang honey supplement improves memory performance and hippocampal morphology in stressed ovariectomized rats

Recently, our research team has reported that Tualang honey was able to improve immediate memory in postmenopausal women comparable with that of estrogen progestin therapy. Therefore the aim of the present study was to examine the effects of Tualang honey supplement on hippocampal morphology and memory performance in ovariectomized (OVX) rats exposed to social instability stress. Female Sprague-Dawley rats were divided into six groups: (i) sham-operated controls, (ii) stressed sham-operated controls, (iii) OVX rats, (iv) stressed OVX rats, (v) stressed OVX rats treated with 17β-estradiol (E2), and (vi) stressed OVX rats treated with Tualang honey. These rats were subjected to social instability stress procedure followed by novel object recognition (NOR) test. Right brain hemispheres were subjected to Nissl staining. The number and arrangement of pyramidal neurons in regions of CA1, CA2, CA3 and the dentate gyrus (DG) were recorded. Two-way ANOVA analyses showed significant interactions between stress and OVX in both STM and LTM test as well as number of Nissl-positive cells in all hippocampal regions. Both E2 and Tualang honey treatments improved both short-term and long-term memory and enhanced the neuronal proliferation of hippocampal CA2, CA3 and DG regions compared to that of untreated stressed OVX rats.     

Quantification and characterisation of IgG binding to mould spores by flow cytometry and scanning electron microscopy

The concentration of mould-specific IgG antibodies in serum may objectively indicate mould exposure and can help identifying exposed individuals. Although inhaled spores probably are the most important source of mould exposure, the commonly used methods for detecting mould-specific IgG antibodies are based on extracts from all mould components, with only low contribution from spores. We have developed a flow cytometric method using surface antigens on mould spores for quantifying mould-specific IgG antibodies in serum. Flow cytometric results were evaluated by comparison with ImmunoCap and ELISA measurements. The flow cytometric assay showed a broad linear dose-dependency and correlated moderately to strongly (r=0.41-0.97) with ImmunoCap and ELISA measurements. The IgG antibody binding was studied in detail by immunolabelling in scanning electron microscopy (SEM), revealing that morphology and IgG antibody binding differed among spores, both within and between mould strains. Germination studies by flow cytometry and SEM showed that IgG antibody binding to mould spores was altered during germination due to loss of coat. The present spore based antibody assay are simple and suitable for quantification of mould-specific IgG antibodies in serum, and includes specificity to other and possibly more relevant antigens than existing methods.     

第四脑室外侧隐窝室管膜与哺乳关系的形态学观察

目的观察哺乳期雌性小鼠第四脑室外侧隐窝室管膜形态的变化与哺乳之间的关系.方法HE染色和扫描电镜法.结果光镜下对照组外侧隐窝室管膜细胞单层稀疏排列,哺乳早、中期外侧隐窝室管膜细胞密集,常呈双层或多层排列,在室管膜细胞增厚区上可见均质的絮状物,以哺乳中期最明显,此改变与对照组比较具有显著的差异（P〈0.05）.扫描电镜下对照组外侧隐窝处纤毛稠密,呈簇状分布;哺乳早期纤毛黏连成束,纤毛肿胀增粗,室管膜表面可见到密集的、大小不一的分泌囊泡;哺乳中期分泌囊泡比早期小,囊泡在室管膜表面黏连在一起,成层分布;哺乳末期室管膜细胞的纤毛和微绒毛与对照组相似.结论小鼠第四脑室外侧隐窝室管膜细胞有旺盛的分泌现象,这种改变与哺乳周期密切相关.     

Embryology of the testicular descent

Numerous researchers studied the morphology of the testicular descent, including the possible function of the gubernaculum. However, a clear illustration of this process is still missing. The aim of this paper was to illustrate the embryology of the testicular descent in the rat by scanning electron microscopy. In a first phase of the intra-abdominal testicular descent, the testis moves actively from the lower pole of the kidney towards the bladder neck. In a second inguinal phase the testis enters groin and moves in the developing processus vaginalis peritonei caused by the disappearance of the bulb of the gubernaculums testis.     

Morphometric and structural analysis of Florida manatee spermatozoa

Sperm characteristics, such as sperm morphology and sperm morphometry are important in assessing sperm quality. This is especially important for the management and conservation of endangered and exotic species, like the Florida manatee, where information of this nature is extremely limited. In this study, we fill this knowledge gap to better understand the reproductive physiology of Florida manatees by conducting the first extensive analysis of sperm morphometry and ultrastructure. Sperm were retrieved from the vas deferens of nine recently deceased Florida manatees. Computer-aided sperm morphology analysis (CASMA) was used for morphometric analysis and laser-scanning confocal microscopy and electron microscopy were used for structural and ultrastructural characterization. Our findings reveal new morphometric and structural data for the Florida manatee spermatozoon. Twelve morphometric features of Florida manatee sperm were quantified with some approximately 1.5–2 times larger than those previously reported. Ultrastructurally, the Florida manatee spermatozoon followed a mammalian structural pattern with an ovate-shaped head, midpiece containing 84–90 mitochondria, and a flagellum. However, unique ultrastructural features were identified. Distinct, rectangular-like enlargement of four outer dense fibers surrounding the axoneme was evident, which may provide additional tensile strength to counteract the forces on sperm transiting the female reproductive tract. Likewise, strong localization of F-actin fibers within the midpiece may function to maintain sperm integrity within the female reproductive tract. These findings highlight the potential effects of sexual selective pressures on sperm size and structure in the Florida manatee and provide avenues for research on the occurrence of sperm competition in this species.     

Simple methods to remove microbes from leaf surfaces

Endophytes have been defined as microorganisms living inside plant tissues without causing negative effects on their hosts. Endophytic microbes have been extensively studied for their plant growth-promoting traits. However, analyses of endophytes require complete removal of epiphytic microorganisms. We found that the established tests to evaluate surface sterility, polymerase chain reaction, and leaf imprints, are unreliable. Therefore, we used scanning electron microscopy (SEM) as an additional assessment of epiphyte removal. We used a diverse suite of sterilization protocols to remove epiphytic microorganisms from the leaves of a gymnosperm and an angiosperm tree to test the influence of leaf morphology on the efficacy of these methods. Additionally, leaf tissue damage was also evaluated by SEM, as damaging the leaves might have an impact on endophytes and could lead to inaccurate assessment of endophytic communities. Our study indicates, that complete removal of the leaf cuticle by the sterilization technique assures loss of epiphytic microbes, and that leaves of different tree species may require different sterilization protocols. Furthermore, our study demonstrates the importance of choosing the appropriate sterilization protocol to prevent erroneous interpretation of host-endophyte interactions. Moreover, it shows the utility of SEM for evaluating the effectiveness of surface sterilization methods and their impact on leaf tissue integrity.