Water Relations in Pulvini from Samanea saman: II. Effects of Excision of Motor Tissues

Pulvinar motor tissues of Samanea saman are often excised for in vitro studies of ion transport. Because ion transport may be regulated in part by hydrostatic pressure (P), this study explores how P and water potential (Ψ) change when motor tissues are excised. Water potential (Ψ) of excised extensor and flexor tissues was measured by the Chardakov method and compared with Ψ measurements made on extensor and flexor tissues of intact pulvini (HL Gorton 1987 Plant Physiol 83: 945-950). Ψ values for excised extensor and flexor tissues were always substantially more negative than for the same tissues in intact pulvini. Extensor tissues excised from open pulvini had slightly more negative Ψ than excised flexor tissues, and the opposite was true for closed pulvini. Extensor and flexor tissues elongate immediately when excised from open or closed pulvini, suggesting that in intact pulvini they are constrained from elongating by the nonextensible vascular core. In addition, both tissues in both open and closed pulvini are under compression imposed by oppositely positioned motor tissue. Excision relieves constraint and compression, decreasing P, and thus decreasing Ψ. This finding may explain, at least in part, the difference between Ψ measurements on intact and excised motor tissues. Implications of these data for the planning and interpretation of in vitro experiments requiring excised strips of extensor and flexor tissues are discussed.     

组织的前向散射、后向漫射

人体组织的光学性质是光医学和组织光学领域中的最基本的研究课题之一。当激光与生物肌体相互作用后所产生的各种生物效应,这些即取决于所施加的激光参量,又决定于被作用组织的结构、物理和生物特性。从激光诊断或治疗的角度考虑,由于光或激光只有透过组织,才能到达组织的深部和内部器官。所以,首要解决的问题是组织对光的通透性及其机理的研究。光通过组织时,光强和光的偏振状态会发生变化。令He－Ne激光照射组织,分别在组织的透射方和反射方探测光强．当光垂直（θ＝0°）或以角度θ入射到具有一定厚度的组织时,探测器以α的角度测量前后向的光强分布．根据实验数据分别绘制了前向散射和后向漫射光强的极坐标曲线．当θ－0°、探测器的角度为α＝0°时光的强度最大（前向散射）．旋转探测器的角度（改变α）探测到的光强其图形为一个圆。当入射光的角度θ由0°变到60°时,光的强度降低了31．65％．此时旋转探测器（改变α）探测到的光强分布图形变为椭圆,并且和原点相切,和θ＝0°的图形相比,此时图形的半宽度增加。当入射光的角度θ固定为0°、探测器角度α变化接近180°时光的后向漫射强度最大,其图形为一个圆。比较前向散射和后向漫射的光强分布图可看出光强分布基本上对称。如将两幅     

Vibrational spectroscopy studies of formalin-fixed cervix tissues

Optical histopathology is fast emerging as a potential tool in cancer diagnosis. Fresh tissues in saline are ideal samples for optical histopathology. However, evaluation of suitability of ex vivo handled tissues is necessitated because of severe constraints in sample procurement, handling, and other associated problems with fresh tissues. Among these methods, formalin-fixed samples are shown to be suitable for optical histopathology. However, it is necessary to further evaluate this method from the point of view discriminating tissues with minute biochemical variations. A pilot Raman and Fourier transform infrared (FTIR) microspectroscopic studies of formalin-fixed tissues normal, malignant, and after-2-fractions of radiotherapy from the same malignant cervix subjects were carried out, with an aim to explore the feasibility of discriminating these tissues, especially the tissues after-2-fractions of radiotherapy from other two groups. Raman and FTIR spectra exhibit large differences for normal and malignant tissues and subtle differences are seen between malignant and after-2-fractions of radiotherapy tissues. Spectral data were analyzed by principal component analysis (PCA) and it provided good discrimination of normal and malignant tissues. PCA of data of three tissues, normal, malignant, and 2-fractions after radiotherapy, gave two clusters corresponding to normal and malignant + after-2-fractions of radiotherapy tissues. A second step of PCA was required to achieve discrimination between malignant and after-2-fractions of radiotherapy tissues. Hence, this study not only further supports the use of formalin-fixed tissues in optical histopathology, especially from Raman spectroscopy point of view, it also indicates feasibility of discriminating tissues with minute biochemical differences such as malignant and after-2-fractions of radiotherapy.     

The value of frozen cartilage tissues without cryoprotection for genetic conservation

Animal tissues frozen without cryoprotection are thought to be inappropriate for use as a donor for somatic cell nuclear transfer (SCNT) studies. Cells in tissues that have been frozen without a cryoprotectant are commonly thought to be dead or to have lost genomic integrity. However, in this study we show that the frozen auricular cartilage tissues of anatolian buffalo contain a considerable number of viable healthy cells. The cells in auricular cartilage tissues are resistant to cryo-injury at −80 °C. Primary cell cultures were established from defrosted ear tissues which were frozen without cryoprotectant. The growth and functional characteristics of primary cell cultures are characterized according to cell growth curve, cell cycle analysis, karyotype and GAG synthesis. The results indicate that frozen cartilage tissues could be valuable materials for the conservation of species and SCNT technology.     

生物组织折射率的概念与测量方法评述

折射率作为描述介质光学特性的一个重要物理参量,它在组织光学理论中起着非常重要的作用.随着组织光学研究的深入,生物组织折射率的概念也在不断地完善和发展.本文将主要介绍生物组织折射率的基本概念和测量手段的研究进展情况,明确了生物组织折射率的概念,评述了现有测量方法的优缺点,希望为生物组织折射率问题的进一步研究提供有益参考.     

Complex carbohydrates in cartilaginous and other tissues of cartilage matrix deficiency (cmd/cmd) mice as studied by light microscopic histochemical methods

Summary Mice homozygous for the autosomal recessive gene, cartilage matrix deficiency (cmd/cmd) are characterized by disproportionate dwarfism and cleft palate and are suffered from genetic failure in biosynthesis of cartilagetype proteoglycans. To investigate histochemical aspects of the defects in cartilaginous and other tissues of the mutant mice, complex carbohydrates in the tissues have been studied by methods of light microscopy. As a result of the present investigations, the intercellular matrix of cartilaginous tissues from the mutant was shown to exhibit weaker positive reactions for sulfated and acidic complex carbohydrates, as compared with the corresponding tissues from the control. In certain muscular and nervous tissues from the mutant, the reactions for sulfated complex carbohydrates tended to be weaker in intensity than those in the control. Furthermore, the dermal tissues of the mutant showed apparent mastocytosis. All these results indicate that there exist accessory effects in non-cartilaginous tissues in addition to the defects of cartilaginous tissues in the mutant mice.     

Effect of experimental diabetes on the activity of hexokinase isoenzymes in tissues of the rat

The effect of experimental diabetes on the activity of hexokinase isoenzymes was studied in a wide range of tissues of the rat. In the tissues known to require insulin for glucose phosphorylation, the activity of hexokinase was markedly decreased; the fall being mainly in the Type IV (Glucokinase) in liver and Type II in other tissues, these tissues also exhibit glucose underutilization in diabetes. In the tissues which are commonly known not to require insulin, the activity of Type I hexokinase was significantly increased, these tissues exhibit aspects of glucose overutilization in diabetes in particular kidney and lens. These changes are discussed in relation to Spiro's hypothesis of glucose under and overutilization in tissues in diabetes.     

Evaluation of the suitability of ex vivo handled ovarian tissues for optical diagnosis by Raman microspectroscopy

A pilot Raman microspectroscopy study of formalin-fixed, paraffin-embedded, and deparaffinized sections from the same ovarian normal and malignant tissues was carried out. This approach was considered in order to evaluate the suitability of these ex vivo tissue handling procedures in discrimination as well as biochemical characterization. The spectra of formalin-fixed normal and malignant tissues exhibited no contamination due to formalin, which is indicated by the absence of strong formalin peaks; spectral features also show significant differences for normal and malignant tissues. The differences between spectral profiles of deparaffinized normal and malignant tissues are subtle and spectra show few residual sharp peaks of paraffin. Complete dominance of paraffin swamping signals from tissues was observed in the spectra of paraffin-embedded tissues. Principal components analysis (PCA), which was employed for discrimination of tissue type, provided good discrimination for formalin-fixed and paraffin-embedded tissue spectra. PCA of deparaffinized tissues resulted in a poor classification with significant overlap among the clusters. Thus, this study indicates that formalin fixation is the most suitable among the three procedures employed in the study. Significant differences between spectral profiles of normal and malignant formalin-fixed tissues can not only be exploited for discrimination but can also provide information on biochemical characteristics of the tissues. Deparaffinized tissues provide poor discrimination and information on tissue biochemistry is lost. Paraffin-embedded tissues may provide good discrimination, but predominance of paraffin in the spectra could jeopardize biochemical characterization. Prospectively, as a result of the better availability of paraffin-embedded tissues and problems associated with frozen sectioning of formalin-fixed tissues, the results of this study using paraffin-embedded tissues are very encouraging.     

Review of non-permeating cryoprotectants as supplements for vitrification of mammalian tissues

Vitrification of mammalian tissues is important in the areas of human assisted reproduction, animal reproduction, and regenerative medicine. Non-permeating cryoprotectants (CPAs), particularly sucrose, are increasingly used in conjunction with permeating CPAs for vitrification of mammalian tissues. Combining non-permeating and permeating CPAs was found to further improve post-thaw viability and functionalities of vitrified mammalian tissues, showing the potential applications of such tissues in various clinical and veterinary settings. With the rising demand for the use of non-permeating CPAs in vitrification of mammalian tissues, there is a strong need for a timely and comprehensive review on the supplemental effects of non-permeating CPAs toward vitrification outcomes of mammalian tissues. In this review, we first discuss the roles of non-permeating CPAs including sugars and high molecular weight polymers in vitrification. We then summarize the supplemental effects of non-permeating CPAs on viability and functionalities of mammalian embryos, and ovarian, testicular, articular cartilage, tracheal, and kidney tissues following vitrification. Lastly, challenges associated with the use of non-permeating CPAs in vitrification of mammalian tissues are briefly discussed.     

红树植物白骨壤叶片的解剖结构及其生态适应性

运用石蜡切片的方法对红树植物白骨壤的叶片进行解剖学的观察和研究。结果表明:白骨壤的叶为异面叶;上表皮为复表皮,有厚的角质膜及下皮层;下表皮上有大量的泌盐腺毛;栅栏组织多层,约占叶肉组织的2/3,海绵组织退化;机械组织和输导组织均很发达。反映了白骨壤叶片的结构与其生活的海生环境高度相适应。     

Transcriptomic characterization of gall tissue of Japanese elm tree (Ulmus davidiana var. japonica) induced by the aphid Tetraneura nigriabdominalis

Insect galls are abnormal plant tissues induced by parasitic insect(s) for use as their habitat. In previous work, we suggested that gall tissues induced by the aphid Tetraneura nigriabdominalis on Japanese elm trees are less responsive than leaf tissues to jasmonic acid (JA), which is involved in the production of volatile organic compounds as a typical defensive reaction of plants against attack by insect pests. A comprehensive analysis of gene expression by RNA sequencing indicated that the number of JA responsive genes was markedly lower in gall tissues than in leaf tissues. This suggests that gall tissues are mostly defective in JA signaling, although JA signaling is not entirely compromised in gall tissue. Gene ontology analysis sheds light on some stress-related unigenes with higher expression levels in gall tissues, suggesting that host plants sense aphids as a biotic stress but are defective in the JA-mediated defense response in gall tissues.     

Physical Organization of Two Reservoirs in Serbia as a Crucial Factor in Development of Their Hydrophilic Flora: a Comparative Study

Marine invertebrate herbivores occasionally prefer particular tissues of a given seaweed depending on tissue age. For the intertidal alga Mazzaella parksii (=M. cornucopiae), however, important tissue differences result from abiotic stress: distal tissues of many fronds become bleached under strong irradiance and desiccation during spring and summer low tides. Snails of the genus Littorina (periwinkles) are significant grazers of M. parksii. Through a multiple-choice feeding-preference experiment, we found that periwinkles actively consume bleached tissues, but almost no photosynthetic tissues. This suggests that bleached tissues of M. parksii may support Littorina populations to a good extent during spring and summer. In addition, since photosynthetic tissues are basal, the impact of periwinkles on frond mortality might be lower than if they preferred photosynthetic tissues. Photosynthetic tissues are actively consumed by periwinkles when they are the only food choice, as shown by other researchers. Therefore, retaining bleached tissues for some time might have evolved in M. parksii to divert grazing pressure away from vital tissues.     

Resolving temporal variation in vertebrate diets using naturally occurring stable isotopes

Assessments of temporal variation in diets are important for our understanding of the ecology of many vertebrates. Ratios of naturally occurring stable isotopes in animal tissues are a combination of the source elements and tissue specific fractionation processes, and can thus reveal dietary information. We review three different approaches that have been used to resolve temporal diet variation through analysis of stable isotopes. The most straightforward approach is to compare samples from the same type of tissue that has been sampled over time. This approach is suited to address either long or short-term dietary variation, depending on sample regime and which tissue that is sampled. Second, one can compare tissues with different metabolic rates. Since the elements in a given tissue have been assimilating during time spans specific to its metabolic rate, tissues with different metabolic rates will reflect dietary records over different periods. Third, comparisons of sections from tissues with progressive growth, such as hair, feathers, claws and teeth, will reveal temporal variation since these tissues will retain isotopic values in a chronological order. These latter two approaches are mainly suited to address questions regarding intermediate and short-term dietary variation. Knowledge of tissue specific metabolic rates, which determine the molecular turnover for a specific tissue, is of central importance for all these comparisons. Estimates of isotopic fractionation between source and measured target are important if specific hypotheses regarding the source elements are addressed. Estimates of isotopic fractionation, or at least of differences in fractionation between tissues, are necessary if different tissues are compared. We urge for more laboratory experiments aimed at improving our understanding of differential assimilation of dietary components, isotopic fractionation and metabolic routing. We further encourage more studies on reptiles and amphibians, and generally more studies utilizing multiple tissues with different turnover rates.     

Variation in the distribution of trace elements in hepatoma

There are many reports of reduction of zinc level and rise of copper level in serum of patients with liver disease. However, there are a few reports that compare the trace elements in tumor tissues and nontumor tissues of the liver with hepatoma. We studied trace element distribution in tumor tissues and nontumor tissues of liver with hepatoma and compared them with data from normal liver tissues. Zinc (Zn), copper (Cu), selenium (Se), cadmium (Cd), mercury (Hg), and iron (Fe) were chosen as the trace elements to be observed. We observed falls of Zn, Cd, and Hg levels in tumor tissues and the rise of Cu level as a result of this investigation. Zn, Cd, and Hg levels in tumor tissues were significantly lower than those in nontumor tissues and Zn, Cd, and Hg levels in nontumor tissues were significantly lower than in normal liver tissues. This tendency was clearer for Cd and Hg than for Zn. Although the distribution of Cu was not significant, a distribution contrary to that of Zn was shown. These findings indicate that the distribution of Zn, Cd, and Hg can serve as supportive evidence that could be useful as a tumor marker. Selenium showed almost the same accumulation tendency among tumor tissues, nontumor tissues, and normal livers. Although correlation was observed among most metals in the normal liver, there was almost no correlation in tumor tissues.     

Observations on the early actions of prolactin on RNA and casein synthesis in mouse mammary gland explants

The action of prolactin on RNA synthesis in cultured mouse mammary gland explants becomes manifest when the tissues are exposed only briefly (1 h or less) to prolactin. In contrast, the action of prolactin on casein synthesis only becomes apparent when the tissues are cultured for 6 h or more with prolactin. Once the actions of prolactin on RNA and casein synthesis are initiated, however, these effects persist for hours or days, even when the tissues are subsequently cultured in the absence of prolactin.     

Gene expression analysis in sections and tissue microarrays of archival tissues by mRNA in situ hybridization

Altered expression of genes in diseased tissues can prognosticate a distinct natural progression of the disease as well as predict sensitivity or resistance to particular therapies. Archival tissues from patients with a known medical history and treatments are an invaluable resource to validate the utility of candidate genes for prognosis and prediction of therapy outcomes. However, stored tissues with associated long-term follow-up information typically are formalin-fixed, paraffin-embedded specimen and this can severely restrict the methods applicable for gene expression analysis. We report here on the utility of tissue microarrays (TMAs) that use valuable tissues sparingly and provide a platform for simultaneous analysis of gene expression in several hundred samples. In particular, we describe a stable method applicable to mRNA expression screening in such archival tissues. TMAs are constructed from sections of small drill cores, taken from tissue blocks of archival tissues and multiple samples can thus be arranged on a single microscope slide. We used mRNA in situ hybridization (ISH) on >500 full sections and >100 TMAs for >10 different cDNAs that yielded >10,000 data points. We provide detailed experimental protocols that can be implemented without major hurdles in a molecular pathology laboratory and discuss quantitative analysis and the advantages and limitations of ISH. We conclude that gene expression analysis in archival tissues by ISH is reliable and particularly useful when no protein detection methods are available for a candidate gene.     

RNA isolation from fetal and adult human tissues for transcriptional profiling

Investigations involving rare human tissues that are difficult to acquire due to their scarcity are highly challenging. The need to verify microarray analysis data by additional methods such as immunohistochemical staining and quantitative PCR creates an even greater demand for these valuable tissues. Furthermore, since rare human tissues may come from different sources and may have been processed by variable methods, the comparability of these samples must be verified. The aim of this study was to determine and validate a processing method that allows the analysis of human fetal and adult cardiovascular tissues from different sources that were preserved using varying methods. Due to restricted access to fresh human tissues and the need to accumulate these samples over an extended period of time, we used formalin-fixed paraffin-embedded tissues for gene expression analyses. We analyzed RNA levels from four different age groups: fetal first and second trimester, adolescents, and adults. In this study, we present an improved standard processing procedure for tissue sample processing and analysis of rare human cardiovascular tissues.     

The Genes Raw and Ribbon Are Required for Proper Shape of Tubular Epithelial Tissues in Drosophila

The products of two genes, raw and ribbon (rib), are required for the proper morphogenesis of a variety of tissues. Malpighian tubules mutant for raw or rib are wider and shorter than normal tubules, which are only two cells in circumference when they are fully formed. The mutations alter the shape of the tubules beginning early in their formation and block cell rearrangement late in development, which normally lengthens and narrows the tubes. Mutations of both genes affect a number of other tissues as well. Both genes are required for dorsal closure and retraction of the CNS during embryonic development. In addition, rib mutations block head involution, and broaden and shorten other tubular epithelia (salivary glands, tracheae, and hindgut) in much same manner as they alter the shape of the Malpighian tubules. In tissues in which the shape of cells can be observed readily, rib mutations alter cell shape, which probably causes the change in shape of the organs that are affected. In double mutants raw enhances the phenotypes of all the tissues that are affected by rib but unaffected by raw alone, indicating that raw is also active in these tissues.