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1.
Role of Thidiazuron (TDZ) in inducing adventitious organogenesis in Pongamia was studied. TDZ at different concentrations (0, 0.45, 2.27, 4.54, 6.71, 9.08, 11.35, 13.12 and 22.71 μM) were used for induction
of caulogenic bud formation in deembryonated cotyledon explants. Each cotyledon was cut into three segments and identified
as proximal, middle and distal. Duration of TDZ exposure, influence of the segment and orientation of the explant were studied.
TDZ at 11.35 μM concentration was optimum for the induction of shoots and rapid elongation. Shoots induced at higher concentration
elongated after several passages in growth regulator free medium, thereby extending the period of differentiation. Exposure
of the explant for 20 days yielded more number of buds than 10 days. Proximal segment of the cotyledon was more responsive.
Contact of abaxial surface in the medium was more effective and generated more buds than the adaxial side. Buds differentiated
and elongated on transfer to MS basal medium for 8–12 passages of 15 days each. Rooting and elongation of shoots was achieved
in charcoal supplemented half-strength MS medium. Rooted plantlets survived on transfer to sand soil mixture. The plants were
hardened and transferred to green house. This is the first report on in vitro regeneration of Pongamia pinnata via adventitious organogenesis using TDZ. This protocol may find application in studies in genetic transformation, isolation
of somaclonal variants and in induction of mutants. It also provides a system to study the inhibitory role of TDZ on shoot
differentiation. 相似文献
2.
3.
《Developmental cell》2022,57(2):212-227.e8
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4.
Cultured circular smooth muscle from the rabbit colon 总被引:1,自引:0,他引:1
H. W. Kao S. E. Finn A. M. Gown J. Lechago N. Lachant W. J. Snape Jr. 《In vitro cellular & developmental biology. Plant》1988,24(8):787-794
Summary Although cultured vascular smooth muscle cells have been extensively characterized and investigated, there are very few studies
of cultured intestinal smooth muscle cells. The aim of this study was to culture colonic smooth muscle (CSM) cells from the
rabbit colon. Freshly isolated CSM cells from the circular muscle layer of the distal colon were prepared by collagenase digestion.
In primary culture, CSM cells attached to the culture vessels by 48 to 72 h, proliferated by 3 to 7 d, and reached confluency
by 14 to 17 d with a “hill-and-valley” pattern. Spontaneous contractions were not observed at any time at 21° or 37° C. Confluent
primary cultures were greater than 95% CSM cells, as identified by intensely positive immunofluorescent staining to smooth
muscle actin-specific CGA7 and muscle-specific HHF-35 monoclonal antibodies. Transmission electron microscopy of freshly isolated
and proliferating CSM cells revealed ultrastructural features consistent with smooth muscle cells. We successfully cultured
CSM cells of the rabbit from freshly isolated cells and validated these CSM cells by electron microscopy and immunocytochemical
staining. These highly pure primary cultures may be used to investigate numerous aspects of CSM cell metabolism and physiology.
These studies were supported by the National Institutes of Health grant to the Inflammatory Bowel Disease Center (Bethesda,
MD) P30-AM-32200 and R01-DK-31147. Dr. Kao is the recipient of a Research Career Development Award from the National Foundation
for Ileitis and Colitis, Inc. A preliminary report of this work was presented at the American Motility Society Meeting, Houston,
TX, in October 1986, and appeared in abstract form inGastroenterology 91: 1057; 1986. 相似文献
5.
C. Bevan R. K. H. Kinne R. E. Shetlar E. Kinne-Saffran 《Journal of comparative physiology. B, Biochemical, systemic, and environmental physiology》1989,159(3):339-347
Summary A membrane fraction, rich in brush border membranes, was prepared from renal proximal tubules of the spiny dogfish,Squalus acanthias, and the sodium-proton exchange mechanism in these membrane vesicles was investigated by both a rapid filtration technique and the fluorescence quenching of acridine organe.22Na+ uptake was stimulated by an outwardly directed H+ gradient, and was inhibited by amiloride at a single inhibitory site with an apparentK
i
of approximately 1.7×10–5
M. In the presence of an H
i
+
>H
o
+
gradient, the
of the Na+/H+ exchanger were 9.7±0.8 mM and 48.0±12.0 nmol·mg protein–1·min–1, respectively. The uptake of Na+ was electroneutral in the presence of a H+ gradient, indicating a stoichiometry of 1. In the fluorescence studies, quenching of acridine orange occurred in the presence of an outwardly directed Na+ gradient which was inhibited by amiloride. Thus, an electroneutral Na+/H+ exchanger with properties similar to those found in the mammalian kidney is also present in the spiny dogfish and may contribute to the urinary acidification of this marine animal. 相似文献
6.
A Rambourg Y Clermont M Chrétien 《Biology of the cell / under the auspices of the European Cell Biology Organization》1989,65(3):247-256
The tridimensional structure of the Golgi apparatus has been studied in the absorptive cells of the mouse colon by means of reduced osmium postfixation and phosphatase cytochemistry. In thick sections of tissue impregnated with osmium tetroxide or treated with a technique to demonstrate TPPase activity, the Golgi formed a continuous ribbon-like structure capping the upper pole of the nucleus. Along the longitudinal axis of this ribbon, compact zones made up of superposed flattened saccules alternated with less compact zones which consisted of highly perforated saccules or bridging anastomosed tubules. In the cis-trans axis, the following elements were observed: (1) a cis element consisting of a continuous osmiophilic tubular network; (2) two or three subjacent elements selectively perforated by wells; (3) a trans compartment made up of two or three TPPase-reactive sacculotubular elements, some showing a "peeling-off" configuration. In some regions, the first flattened saccule of this trans compartment displayed discrete ovoid dilatations, located in compact zones and containing a dense granulofibrillar material; in the subjacent elements this material was seen concentrated in nodular swellings, at the intersection of the meshes of anastomosed membranous tubules. 100-300 nm vesicles containing a similar dense granulofilamentous material were observed in the trans Golgi zone and interspersed in the supranuclear cytoplasm between the Golgi zone and the apical surface of the cell. Smaller vesicles 80-100 nm in diameter containing a fine dusty material were also seen in proximity. These morphological observations suggested that at least two kinds of material were segregated in the saccules of the trans compartment and packaged in vesicles of two class sizes that detached from the Golgi stack on its trans aspect. 相似文献
7.
A method for the rapid establishment of normal adult mammalian colonic epithelial cell cultures 总被引:6,自引:0,他引:6
Alda Vidrich Rajeswari Ravindranath Kianbanoo Farsi Stephan Targan 《In vitro cellular & developmental biology. Plant》1988,24(3):188-194
Summary Normal colonic epithelial cell cultures of mammalian origin are required to facilitate the study of both normal cellular functions
as well as pathogenesis of certain (human) colonic diseases. To date, little information is available regarding the growth
requirements of colonic epithelial cells in culture of eitehr animal or human origin. Such data would enable the development
of a long-term culture system for these cells. In this study, we present methodology that results in the establishment of
homogeneous cultures of adult rabbit colonic epithelial reproducibly, quickly, and in quantity. The epithelial nature of the
cultures is unambiguously established by intermediate filament typing using antikeratin antibodies. Such culutres can now
be used for a variety of functional studies as well as to investigate the growth requirements of colonic epithelial in culture.
This work was supported by the Blinder Foundation for Crohn’s Disease Research, Harbor UCLA IBD Center (AM 36200) and grant
AM 27806 from the National Institutes of Health, Bethesda, MD. 相似文献
8.
在豚鼠肠系膜下神经节(IMG)及其支配的结肠段联合标本上,对IMG细胞内电位与肠段纵肌或环肌舒缩活动进行了同步记录。实验结果表明:(1)肠段预置张力为零时,约50%IMG细胞有自发的快兴奋性突触后电位(EPSP)活动,切断结肠神经或以筒箭毒(50μmol/L)灌流IMG后消失;(2)筒箭毒或低钙高镁溶液阻断神经节传递时,环肌节律性收缩幅度增大,节律变慢,但对纵肌节律性收缩无明显影响,(3)串刺激节前神经,在IMG细胞引起一串快EPSP或动作电位并常跟随迟慢的EPSP,同时,纵肌在0.1-0.2s潜伏期后出现迅速的、时程基本与动作电位串一致的舒张波,后者在筒箭毒灌流IMG后消失,而环肌运动可见舒张、舒张波延长或收缩波增大。结果提示:IMG不仅中继经典的胆碱能传出功能,还参与以胆碱能传递为中介的肠-肠反射,该反射活动的传出效应主要在于抑制环肌收缩。 相似文献
9.
Terry B. White Dianne K. Hammond Hernán Vásquez Henry W. Strobel 《Molecular and cellular biochemistry》1991,102(1):61-69
Cytochrome P450 is known to cause carcinogen activation and correspondingly increased cancer risk in animal models. In order to determine whether P450 in the colon may be involved in cancer development in the human, the human colon cell line LS174T was examined for the presence of various cytochromes P450. Two isozymes of P450 were identified in the human cell line. Expression of P450IAl or IA2 was increased by treatment of the cell line with benzanthracene; the induction was demonstrated by an increase in RNA hybridizing to a probe for P4501Al and by ethoxyresorufin deethylation activity. Western analysis of microsomes isolated from human colon tissue also demonstrated the presence of P4501A1, as well as a form which cross-reacted to an antibody to human P450IIC9. Another isozyme, P450IIE1, was identified by polymerase chain reaction amplification of RNA from LS174T cells. These results underscore the presence of cytochromes P450 in colonic tissue and provide a basis for the involvement of isozyme-specific P450 mediated reactions in carcinogenesis of the colon.Some of the data presented here were taken from a thesis submitted by D.K.H. in partial fulfillment of the requirements for the Ph.D. degree in the University of Texas Graduate School of Biomedical Sciences. 相似文献
10.
The haematology and phospholipase activity and mast cell numbers of the small intestine and colon of rats was studied 10 days after infection with various numbers of larvae of N. brasiliensis. A significant reduction in the RBC occurred after infections with 200 and 5000 larvae but not with 1000 larvae. Hb was significantly reduced after infection with 200 larvae and increases in the MCV and MCH indicated the development of a macrocytic anaemia. Reticulocyte count was increased at all levels of infection except after 200 larvae. WBC was increased at all levels of infection except in the 5000 larvae group. Lymphocytes were significantly increased in all groups except those infected with 5000 larvae. Neutrophils increased only at the lower levels of infection. The most marked changes occurred in eosinophil numbers, significant increases occurring with increasing levels of infection. However, after infection with 5000 larvae the numbers were significantly lower than after infection with 200 or 1000 larvae. Phospholipase activity, which is believed to be related to tissue eosinophil levels, was significantly increased at all infection levels in the proximal small intestine. Significant increases in the distal ileum and colon occurred mainly after infection with 1000 and 5000 larvae. Mast cell numbers did not change significantly at any infection level. It is suggested that the pathology observed, here in the form of anaemia, is multifactorial in origin and is largely a function of the immune response, the development and expression of which is dependent on the level of infection, with suppression of immune damage occurring at the high levels of infection when pathogenesis may involve a direct effect of the worms. 相似文献