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Distribution of phosphodiesterase I in normal human tissues   总被引:1,自引:0,他引:1  
Phosphodiesterase I (PDE I) is an exonuclease capable of hydrolyzing a variety of phosphate ester and pyrophosphate bonds. Cell fractionation and histochemical studies in animal tissues have localized PDE I in the plasma membrane of various epithelia. This suggests a role for the enzyme in active transport. Distribution of PDE I in human tissues has not previously been studied. We have produced a polyclonal antiserum to bovine intestinal PDE I and have demonstrated crossreactivity with the human intestinal enzyme. This polyclonal antiserum was used in PAP immunocytochemistry to localize immunoreactive PDE I in a variety of human tissues. Localization was prominent in the gastrointestinal tract, including the cytoplasm of gastric mucosa parietal cells, cytoplasm of surface epithelium and isolated crypt cells in small intestine, and the colonic epithelial cytoplasm and brush border. Parotid gland acinar cells and scattered ductal cells showed positive cytoplasmic staining. Acinar and scattered pancreatic islet cells contained immunoreactive PDE I, as did Kupffer cells of the liver sinusoids. Immunoreactive PDE I was found in all vascular endothelia. The epithelium of the urinary tract showed extensive immunoreactivity. This included the distal convoluted and collecting tubules of the kidney, and ureteral and bladder urothelium. In previous histochemical studies of animal tissues, no evidence of PDE I activity was noted in male or female reproductive tract. In this study, immunoreactive PDE I was localized to human Sertoli cells and to basal epithelium of the epididymis and prostate acini. Fallopian tube epithelium of female reproductive tract also demonstrated immunoreactive PDI I, as did several cell types in term placenta. Our immunocytochemical results with human tissues differ significantly from previous histochemical studies in animal tissues, principally in the genitourinary system. This may be due in part to the different detection systems employed as well as the higher sensitivity of the immunoperoxidase technique. This underscores the importance of adjunct techniques in tissue surveys. The widespread epithelial distribution of immunoreactive PDE I detected by this polyclonal antibody implies an integral role in cell function, probably in active transport.  相似文献   

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BackgroundTrace elements (TE) in the human body provide a connecting link between the environment, lifestyle and biochemical modulation of homeodynamics. On the other hand, many non-essential (toxic) elements are linked to numerous diseases. Our study tried to identify differences in TE levels between healthy old and young Wistar rats in blood and the tissues of kidney, liver, heart, and testicles. Furthermore, we wanted to see if there were age-related differences in correlations between essential and/or non-essential (toxic) TE within and between mentioned tissues.MethodsWe used 28 healthy male Wistar rats which were divided into two age groups: young, aged 10 weeks (n = 15) and old, aged 36 months (n = 13). The animals were sacrificed under general anesthesia and the blood samples, and samples from the tissues of the heart, kidneys, testicles, and liver were used for the determination of TE content in them. Analysis of the 16 elements was performed by inductively coupled plasma mass spectrometry (ICP-MS).ResultsToxic elements in old rats (As, Hg, and Cd) were significantly higher in all of the tissues where the difference in levels of these elements was found. Tissues of the kidney and liver had the most correlations between TE in old and young rats, respectively. In both old and young rats, arsenic was the toxic element that had most of the correlations with other essential or non-essential elements. In old rats, most of the TE correlations were detected between the tissues of the kidney and heart (11 correlations), while in young rats most of the correlations were observed between the tissues of kidney and liver, and kidney and testicles (with 9 correlations both).ConclusionsOur study has found significant changes in levels of trace elements in all of the mentioned tissues, with kidney and testicles being the tissues with the most TE differences between the two aged groups. This and other similar studies should encourage other investigators to evaluate the mutual connections between TE and physiological, or the “unhealthy” aging. More studies with more tissues included, more biomarkers of the systemic function, and even molecular methods are needed to provide the answers to numerous questions relating to TE and aging.  相似文献   

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Trace elements are movable from the bone before or even after death. S is most constant and Si is possible essential in maintenance of the back bone.  相似文献   

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In the present study, we investigated Langerhans cells (LCs) in the epidermal component of human atrophic scars, comparing them with those in control skin and normotrophic scars. A preliminary analysis of the histological features was first carried out on vertical serial sections, stained with hematoxylin and eosin. The total epidermal thickness and the thickness of the single epidermal layers were then measured, by means of a digitizing tablet and a morphometric program run on an Apple IIe computer. These parameters were found to be significantly lower (40%) in atrophic scars, if compared to control skin and normotrophic scars (p less than 0.05). CDla-positive and HLA-DR-positive LCs were marked by indirect immunofluorescence. Their position among the epidermal layers, their dimensions, their density and their morphology were examined. In atrophic scars, LCs were densely and evenly distributed in all the epidermal layers. Their density was increased (about 1200 cells/mm2 of epidermal area), if compared to control skin and normotrophic scars (both 300-400 cells/mm2 of epidermal area; p less than 0.001). The CDla-positive definite cell bodies, exhibiting an unstained nucleus, were as large as those evidentiated in the normotrophic scars and twice as much the control skin values (p less than 0.001). The present results provide morphological data that distinguish atrophic scars from control skin and normotrophic scars, and suggest an involvement of the Langerhans cells in this particular case of pathological scarring.  相似文献   

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Tendons and ligaments are key structures in promoting joint movement and maintaining joint stability. Although numerous reviews have detailed their structure, molecular composition, and biomechanical properties, far less attention has been paid to their content of trace elements. Tendons and ligaments are generally rich in calcium, sulfur, and phosphorus, although there are intriguing differences between one tendon/ligament and another. Furthermore, there can be significant regional variations that correlate with the presence or absence of fibrocartilage in the “wraparound” regions of tendons or ligaments, where they change direction and press against bone. Here, their sulfate and calcium contents are particularly high. This is undoubtedly associated with the high levels of proteoglycans that are found in these cartilaginous tissues and the occasional presence of sesamoid bones within them.  相似文献   

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Research on trace elements in chemical evolution is reviewed from three points of view. They are:(i) the origin of the essentiality of trace elements in present biological systems; (ii) the possible roles of trace elements in chemical evolution; and (iii) the origin of enzymatic activity with metal ions,i.e., the origin of metalloenzymes.  相似文献   

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Role of sulfatide in normal and pathological cells and tissues   总被引:1,自引:0,他引:1  
Sulfatide is 3-O-sulfogalactosylceramide that is synthesized by two transferases (ceramide galactosyltransferase and cerebroside sulfotransferase) from ceramide and is specifically degraded by a sulfatase (arylsulfatase A). Sulfatide is a multifunctional molecule for various biological fields including the nervous system, insulin secretion, immune system, hemostasis/thrombosis, bacterial infection, and virus infection. Therefore, abnormal metabolism or expression change of sulfatide could cause various diseases. Here, we discuss the important biological roles of sulfatide in the nervous system, insulin secretion, immune system, hemostasis/thrombosis, cancer, and microbial infections including human immunodeficiency virus and influenza A virus. Our review will be helpful to achieve a comprehensive understanding of sulfatide, which serves as a fundamental target of prevention of and therapy for nervous disorders, diabetes mellitus, immunological diseases, cancer, and infectious diseases.  相似文献   

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Concentrations of the elements Ca, Sr, Mg, Zn and Cu were determined in excavated hair specimens and adherent, most probably soil remains from two sites in Germany. Though soil contamination obviously has occurred, the two groups could be distinguished by differential trace element contents in the hair samples. The trace element concentrations might be interpreted in terms of nutritional intake, the results being corroborated by preceding bone analyses and the different local and social settings. Hair decomposition is discussed.  相似文献   

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Multielement analysis was performed on human milk collected on 5-9-d postpartum from 51 Japanese females using inductively coupled plasma (ICP) mass spectrometry (MS), ICP atomic emission spectrometry (ICP-AES) and fluorometry. Thirty-one elements were detected by these analytical methods in milk. Twelve elements (Na, Mg, P, S, K, Ca, Cu, Zn, Se, Sr, Rb, and Mo) were detected in all of the samples. Al, Cs, and Ba were the elements detected by ICP-MS in more than half of the samples. Multiple regression analysis extracted biological attributes of mother and infant, such as maternal stature, maternal wt, or infant's birth wt, as statistically significant factors contributing to the variation in elemental concentration in milk. However, the rates of contribution were small in all cases. It was concluded that the biological attributes of mother and infant examined in this study were not the major factors that contribute to elemental variation in human milk.  相似文献   

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Although various proteins and some electrolytes have been measured in human saliva, little systematic data about the major and minor elemental components of this body fluid have been obtained. In order to obtain such data, concentrations of C, Na, P, Cl, K, Ca, Sc, Cr, Fe, Co, Zn, Se, Br, Rb, Sb, I, and Cs in human parotid saliva were measured by instrumental nuclear methods. The data obtained confirmed the relative lack of Zn in saliva of patients with hypogeusia (decreased taste acuity) and suggested that concentrations of Na, Cl, Br, and Ca followed the order: normals > hypogeusia > hyposmia (decreased smell acuity). To compare concentrations of elements in saliva with those in blood and urine, absolute concentrations were normalized to that of Na through the use of a concept called an enrichment factor. On this basis, parotid saliva is relatively depleted in Se, Zn, and Fe and enriched for most other elements relative to blood plasma indicating that the fluid is not simply a transudate of blood plasma. Using this same technique, saliva composition was found more similar to urine than blood plasma, being relatively depleted in Se, Cs, and Co, being enriched in I, Br, and Cr and having about the same relative concentrations of P, Cl, Zn, Fe, Ca, K, and Rb. As the total body concentrations of many of the enriched elements in saliva are extremely small, their enrichment in saliva suggests special roles for these elements in the oral cavity. Because of its accessibility, ease of collection, and interaction with some body constituents, saliva represents a useful, albeit neglected, tool in the diagnosis of some physiological and pathological changes in body function and in understanding important aspects of trace metal metabolism.  相似文献   

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The immunofluorescent staining of the human normal testis shows that both peritubular and tubular cells bind antimyosin-like antibodies. The same cells are provided with a large amount of microfilaments within the cytoplasm. The thin microfilaments observed by electron microscopy in various cells of the human testis likely correspond to the sites of immunofluorescent staining. In pathological specimens there can be observed a decrease in peritubular smooth muscle cells associated with a decrease in cytoplasmic microfilaments and in the immunofluorescent staining of some cells.  相似文献   

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