scholarly journals Anatomical, morphological, and physiological changes in colchicine-treated protocorm-like bodies of Catasetum pileatum Rchb.f. in vitro

2020 ◽  
Vol 6 (1) ◽  
pp. 1840708
Author(s):  
Masoumeh Kazemi ◽  
Behzad Kaviani
2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Jungwook Paek ◽  
Joseph W. Song ◽  
Ehsan Ban ◽  
Yuma Morimitsu ◽  
Chinedum O. Osuji ◽  
...  

AbstractHere we present a microengineered soft-robotic in vitro platform developed by integrating a pneumatically regulated novel elastomeric actuator with primary culture of human cells. This system is capable of generating dynamic bending motion akin to the constriction of tubular organs that can exert controlled compressive forces on cultured living cells. Using this platform, we demonstrate cyclic compression of primary human endothelial cells, fibroblasts, and smooth muscle cells to show physiological changes in their morphology due to applied forces. Moreover, we present mechanically actuatable organotypic models to examine the effects of compressive forces on three-dimensional multicellular constructs designed to emulate complex tissues such as solid tumors and vascular networks. Our work provides a preliminary demonstration of how soft-robotics technology can be leveraged for in vitro modeling of complex physiological tissue microenvironment, and may enable the development of new research tools for mechanobiology and related areas.


1978 ◽  
Vol 235 (6) ◽  
pp. F548-F556 ◽  
Author(s):  
A. R. Denniss ◽  
L. H. Schneyer ◽  
C. Sucanthapree ◽  
J. A. Young

The effects of norepinephrine and isoproterenol on the transepithelial potential difference (PD) and the net transepithelial fluxes of Na, K, Cl, and HCO3 of the main ducts of the submandibular glands of rats and rabbits have been studied by microperfusion of ducts incubated in vitro in an artifical bathing medium. In the rabbit duct, both catecholamines caused depolarization and reduced transepithelial Na reabsorption at concentrations above 10(-29) M. In the rat duct, norepinephrine reduced PD and net Na reabsorption and, in addition, inhibited net K secretion at concentrations of 10(-7) M and above. Isoproterenol also depolarized the duct and reduced net K reabsorption, but at concentrations of 10(-9) M it stimulated net Na reabsorption, whereas at concentrations of 10(-4) M it inhibited Na reabsorption. The stimulation caused by isoproterenol at low concentrations could be blocked by prior administration of propranolol. The results suggest that electrolyte transport, by both rat and rabbit ducts, may be influenced not only by sympathetic nerve activity but also by physiological changes in the concentrations of circulating catecholamines. Inconsistencies in the literature regarding the sensitivity of the rabbit duct to catecholamines and the response of the rat duct to isoproterenol have now been resolved.


Reproduction ◽  
2002 ◽  
pp. 683-689 ◽  
Author(s):  
M Ozawa ◽  
M Hirabayashi ◽  
Y Kanai

Mammalian preimplantation embryos are sensitive to maternal and direct heat stress. However, the mechanisms by which heat stress affects early embryonic development in vivo or in vitro are unknown. This study examined whether heat-stress-induced loss of developmental competence in mouse embryos was mediated by physiological changes in the maternal environment or by high temperatures alone. After fertilization, zygotes at the same stage were heat-stressed at 39.5 degrees C for 12 h either maternally (measured by maternal rectal temperature) or directly in culture. Zygotes in each group were cultured at 37.5 degrees C for a further 84 h to assess their developmental ability. Neither type of heat stress affected the first cleavage rate. However, the proportion of embryos that developed to morulae or blastocysts was significantly lower in the maternally heat-stressed group, but not in the directly heat-stressed group. Moreover, maternal heat stress significantly reduced intracellular glutathione concentrations and enhanced hydrogen peroxide concentrations in both zygotes and two-cell embryos that were recovered immediately after heat stress or 12 h later, respectively. In contrast, direct heat stress had little effect on concentrations of glutathione or hydrogen peroxide in cultured early embryos. These results demonstrate that maternal heat stress at the zygote stage reduces the developmental ability of mouse embryos via physiological changes in the maternal environment that lead to an increase in intracellular oxidative stress on the embryo.


2018 ◽  
Vol 90 (4) ◽  
pp. 3449-3462 ◽  
Author(s):  
ADALVAN D. MARTINS ◽  
JOÃO PAULO R. MARTINS ◽  
LUCAS A. BATISTA ◽  
GABRIELEN M.G. DIAS ◽  
MIRIELLE O. ALMEIDA ◽  
...  

1928 ◽  
Vol 47 (4) ◽  
pp. 593-610 ◽  
Author(s):  
Hans Smetana

The results of these observations may be briefly summarized as follows: Feeding of hematoporphyrin to white mice over long periods of time produced no apparent changes in these animals and had no effect upon their sensitivity to light. Albino and slightly pigmented mice and rats injected with hematoporphyrin were protected from the rays of the sun by staining them a blue-black color with Verhoeff's hematoxylin. The dioxyphenylalanine (Dopa) reaction revealed no changes in the cutaneous pigment of animals injected with hematoporphyrin and exposed to sunlight, kept in the dark or diffused daylight. It was therefore assumed that the natural pigment of the skin plays only a physical rôle in protecting animals injected with hematoporphyrin from sunlight. Exposure to sunlight of only the intestine and mesentery of a cat under ether anesthesia, which had been injected with hematoporphyrin, was followed by death of the animal. Repeated injections into white mice of large amounts of blood from guinea pigs in hematoporphyrin shock failed to produce symptoms of hematoporphyrin shock. In a parabiosis experiment, one of a pair of white rats promptly developed characteristic symptoms and died when injected with hematoporphyrin and exposed to sunlight, while the other animal, which was protected from light, but whose circulation had been demonstrated to connect freely with that of its partner, showed no changes during the entire procedure. It has, therefore, been impossible, so far, to demonstrate any substance present in the blood of animals in hematoporphyrin shock which is capable of reproducing this condition in other animals when introduced into the circulation. Injection of hematoporphyrin followed by exposure of the entire animal to sunlight has been found to produce physiological changes in cats similar to those observed in traumatic shock. There promptly occurred a rapid fall of blood pressure to a very low level and marked lowering of body temperature. The venous blood was found to be poor in oxygen, rich in carbon dioxide and to show low carbon dioxide-combining power. The respiration, which first was accelerated, later on became deep and irregular. The reflexes and typical blood pressure responses to cutaneous and vagal stimulation could always be obtained until death. Marked diminution of oxygen and increase of carbon dioxide content were found to occur in mixtures of blood and hematoporphyrin exposed in vitro to sunlight. These changes in the blood, identical with those occurring in vivo during hematoporphyrin shock, support Gaffron's views regarding the effect produced by the combined action of hematoporphyrin and light, but do not further elucidate the nature of the manner in which such alterations take place. Unsuccessful attempts were made to produce, in both cats and dogs, physiological changes similar to those observed in hematoporphyrin shock by exposing only the blood flowing through a quartz glass cannula, connecting the femoral artery and vein, to strong arclight and sunlight. In another series of animals, which were first injected with hematoporphyrin, exposure of the circulating blood alone to arclight or sunlight did not produce hematoporphyrin shock, although the blood pressure did fall to an unusually low level in one instance. No changes were found to occur in the amount of non-protein nitrogen, sugar or creatinine of the blood of animals in hematoporphyrin shock.


2009 ◽  
Vol 12 (17) ◽  
pp. 100-105
Author(s):  
Huong Thi Ngoc Nguyen ◽  
Mai Thi Bach Vo

Morinda citrifolia L. is a valuable medicinal plant, used to treat many diseases, such as sleeplessness, backache, high pressure... Recent studies show that Morinda citrifolia L. can regenerate adventitious roots in-vitro. To study the root morphogenesis in Morinda citrifolia L., we examined the effects of some auxin on regeneration of adventitious root in hypocotyl and leaf. The results showed that the concentration of 0,1mg/l NAA stimulated the formation of callus and primordia root in hypocotyl and leaf, in the first week, and the elongation of primordia root in the second week. Roles of respiration rate and endogenous hormones were discussed to understand the physiological changes in the formation of adventitious root.


2016 ◽  
Vol 19 (2) ◽  
pp. 33-43
Author(s):  
Suong Thi Tuyet Ha ◽  
Mai Thi Bach Vo

Under the influence of plant hormones, after 8 weeks of in vitro culture, the growth of breadfruit shoot (Artocarpus altilis (Park.) Fosberg) was very different. With shoots that were cultured on 1 mg/L BA medium after 10 days of being transferred to ½ MS supplemented with 10 mg/L BA medium, the percentage of shoot development was the highest (86.8 %), and the secretion of phenolic compounds or forming callus were not observed. On the ½ MS supplemented with 12 mg/L BA medium, shoots growed strongly and healthily but the secretion of phenolic compounds and the forming of callus affected the ability of the shoot development. On the ½ MS supplemented with 0.45 mg/L BA, 0.6 mg/L Kinetin (Kin) medium and on the ½ MS supplemented with 0.45 mg/L BA, 0.6 mg/L Kin, 0.35 mg/L GA3 medium, the percentage of shoot developed were lower than those on the ½ MS supplemented with 10 mg/L medium. The addition of 0.35 mg/L GA3 in the culture medium help to appear the lateral more than the remaining experiments. Roles of respiration rate and endogenous hormones were discussed to understand the physiological changes in the in vitro culture shoots breadfruit.


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