Faculty Opinions recommendation of Transient activation of beta -catenin signaling in cutaneous keratinocytes is sufficient to trigger the active growth phase of the hair cycle in mice.

Author(s):  
Bruce Morgan
2019 ◽  
pp. 223-228
Author(s):  
Dmitry Dergachev ◽  
Marina Larkina ◽  
Valerii Petrov ◽  
Mikhail Pankin

Исследования интродуцированного японского сорта винограда Кёхо выполнены в нестабильных погодных условиях умеренно континентального климата юга России, в Черноморской зоне виноградарства Краснодарского края в условиях температурного и водного стрессов 2018 года. В период активной вегетации (май - август) сумма активных температур воздуха была на 197 °С больше среднемноголетней нормы, количество атмосферных осадков было меньше нормы в 3,7 раза и составило 47 мм. В аномальных погодных условиях интродуцированный сорт винограда Кёхо показал высокую адаптивность к нестабильным погодным условиям в форме активного роста и прохождения фенологических циклов. При остром дефиците атмосферных осадков и повышенной инсоляции продолжительность вегетации винограда Кёхо от распускания почек до полной физиологической зрелости ягод была равна 119 дней, на 5 дней меньше, чем у контрольного сорта Бригантина и на 3 дня меньше, чем в среднем по большой группе столовых сортов разного эколого-географического происхождения, расположенных рядом на Анапской ампелографической коллекции. Начало фазы распускания почек, роста побегов и соцветий наблюдалось 15 апреля, у контрольного сорта на 4 дня раньше, у сортов ампелографической коллекции на 6 дней позже. Продолжительность этой фазы вегетации у изучаемого сорта составила 54 дня, больше на 11 дней чем у контрольного сорта и на 9 дней чем у столовых сортов ампелоколлекции. Цветение у сорта Кёхо начиналось 7 июня, на 15 дней позже чем у контрольного сорта Бригантина и на 3 дня чем у группы столовых сортов на ампелоколлекции. Продолжительность периода от начала цветения до начала созревания ягод у сорта Кёхо в экологических условиях 2018 года составила 50 дней, что на 4 дня короче, чем у контрольного сорта и на 3 дня короче, чем у сортов на ампелоколлекции. Интенсивность роста ягод была более высокой по сравнению с контролем и группой столовых сортов в ампелоколлекции. Полная физиологическая зрелость ягод у изучаемого сорта наступила 11 августа, практически одновременно с контролем - 12 августа.The study of introduced Japanese grapevine cultivar ‘Kёho’ was carried out in unstable weather conditions of moderately continental climate of the South of Russia, in the Black Sea viticultural zone of the Krasnodar Krai under temperature and water stress of 2018. During the active vegetation season (May - August), the accumulated effective temperatures made 197 ° С above the long-time average annual, the amount of precipitation was 3.7 times less than normal, and amounted to 47 mm. Under the effect of abnormal weather conditions, the introduced grapevine cultivar ‘Kёho’ demonstrated high adaptability to erratic weather conditions during the active growth phase and passage of phenological cycles. Under acute atmospheric precipitation deficit and increased insolation, the duration of ‘Kёho’ grapevine vegetation from bud break to full physiological berry ripeness made 119 days, which is 5 days less as compared to control cultivar ‘Brigantina’ and 3 days less than the average for a large group of table cultivars of various ecological and geographical origin, located in the nearby Anapa ampelographic collection. The start of the bud break, shoot and inflorescence growth phase was observed on April 15; it happened 4 days earlier for the control cultivar, and 6 days later for the cultivars in the ampelographic collection. The duration of this vegetation phase for the studied cultivar was 54 days, which by 11 days exceeded that of the control cultivar and by 9 days that of the table cultivars in the ampelographic collection. The bloom of ‘Kёho’ began on June 7 - 15 days later than that of the control cultivar ‘Brigantina’ and 3 days later as compared to the group of table cultivars in the ampelographic collection. Duration of the early bloom to veraison period of ‘Kёho’ grapes in the ecological conditions of 2018 made 50 days, which was 4 days shorter than that of the control cultivar and 3 days shorter as compared to the cultivars in the ampelographic collection. The berry growth was more intensive as compared to the control and the group of table cultivars in the ampelographic collection. Berries of the studied cultivar reached full physiological ripeness on August 11, almost simultaneously with the control - on August 12.


Development ◽  
1964 ◽  
Vol 12 (3) ◽  
pp. 465-474
Author(s):  
Elizabeth Johnson ◽  
F. J. Ebling

Hair growth is intermittent; periods of activity when the follicle is producing the hair alternating with periods of rest when the dead hair is retained. In the rat, hair growth occurs in a series of waves which start ventrally and pass over the flanks to the back (Dry, 1926; Butcher, 1934; Johnson, 1958). It has long been known (Collins, 1918; David, 1934) that if hairs are pulled out of resting follicles activity is induced. To explain this phenomenon, Chase (1955) put forward the view that an inhibitor accumulates in the hair follicle during active growth and is dissipated during the resting stage. Plucking during the resting stage removes this inhibitor along with the club hair, so that activity recommences. Preliminary observations on rats with plucked follicles indicated that the response to plucking varied at different stages of the hair cycle. A detailed study seemed desirable, therefore, in order to test more closely than hitherto the validity of the inhibitor hypothesis.


Data in Brief ◽  
2015 ◽  
Vol 4 ◽  
pp. 430-436 ◽  
Author(s):  
Pauline Marie ◽  
Valérie Labas ◽  
Aurélien Brionne ◽  
Grégoire Harichaux ◽  
Christelle Hennequet-Antier ◽  
...  

MAUSAM ◽  
2021 ◽  
Vol 42 (3) ◽  
pp. 279-286
Author(s):  
A. CHOWDHURY

Curvilinear technique has been applied to rice crop in Bhandara district (Maharashtra) to examine effects of rainfall, maximum temperature and relative humidity. Partial regression curves for estimating the rice yield by taking into account the .combined effect of these three factors have been worked out. It is observed that during the period of active growth rainfall is the most significant factor followed by maximum temperature and relative humidity in that order. The optimum value of total rainfall during the active growth phase was found as 1000 mm and those for maximum temperature and relative humidity as 30.5° C and 81% respectively.


Author(s):  
L. V. Tashmatova ◽  
O. V. Matsneva ◽  
T. М. Khromova ◽  
V. V. Shakhov

The process of clonal micropropagation is influenced by the genotypic characteristics of plants, the composition of nutrient media and the hormonal background at various stages of cultivation. The purpose of the research was to study the regenerative capacity of apple explants of promising varieties. The objects were colon-shaped, immune and scab-resistant apple varieties. The study was carried out in the laboratory of biotechnology of VNIISPK using generally accepted methods. The largest number of viable explants was obtained during the active growth phase, averaging from 72.1 to 88.5%. Maximum contamination was observed in explants introduced in April, regardless of the sterilizing agents. The highest infection rate was in the varieties Orlovskoe рolesie (up to 56.7%), Bolotovskoe (up to 51.4%), Poeziya (up to 43.3%). In the explants introduced in June, the infection was insignificant. Thus, the Imrus and Poeziya varieties showed a small degree of infection after using 0.1% mertiolate solution (1.2% and 2.4%), and the garland and Priokskoe varieties had a 100% yield of pure apexes. Among immune varieties, the highest necrosis was evident in the variety of Imrus (42,1%) and the smallest in the variety Kandil оrlovsky (5,1%) have the largest column-the variety Priokskoe (65.6 per cent) and Vostorg (65,6%). In most of the studied varieties, the greatest necrosis was observed after using 0.1% mertiolate solution. The study was carried out on the background medium QL and Fardzinova recommended for pears. Concentration of BAP 1.0 and 2.0 mg/l. Among the immune varieties, the content of BAP 2.0 mg / l in the QL medium caused the greatest proliferative activity in the varieties Kandil оrlovsky (3.4), Bolotovskoe (4.5) and Orlovskoe рolesie (2.9). Varieties of Imrus and a Veteran of the highest rate of multiplication were obtained in Fardzinova on medium containing BAP in both concentrations. In all varieties, the concentration of BAP 1.0 mg/l contributed to the formation of shoots more than 1 cm, i.e. suitable for rooting.


Development ◽  
1999 ◽  
Vol 126 (20) ◽  
pp. 4557-4568 ◽  
Author(s):  
R. DasGupta ◽  
E. Fuchs

LEF/TCF DNA-binding proteins act in concert with activated beta -catenin, the product of Wnt signaling, to transactivate downstream target genes. To probe the role of activated LEF/TCF transcription factor complexes in hair follicle morphogenesis and differentiation, we engineered mice harboring TOPGAL, a beta -galactosidase gene under the control of a LEF/TCF and beta -catenin inducible promoter. In mice, TOPGAL expression was directly stimulated by a stabilized form of beta -catenin, but was also dependent upon LEF1/TCF3 in skin. During embryogenesis, TOPGAL activation occurred transiently in a subset of LEF1-positive cells of pluripotent ectoderm and underlying mesenchyme. Downgrowth of initiated follicles proceeded in the absence of detectable TOPGAL expression, even though LEF1 was still expressed. While proliferative matrix cells expressed the highest levels of Lef1 mRNAs, LEF1 concentrated in the precursor cells to the hair shaft, where TOPGAL expression was co-induced with hair-specific keratin genes containing LEF/TCF-binding motifs. LEF1 and TOPGAL expression ceased during catagen and telogen, but reappeared at the start of the postnatal hair cycle, concomitant with precortex formation. In contrast to hair shaft precursor cells, postnatal outer root sheath expressed TCF3, but not TOPGAL. TCF3 was also expressed in the putative follicle stem cells, and while TOPGAL was generally silent in this compartment, it was stimulated at the start of the hair cycle in a fashion that appeared to be dependent upon stabilization of beta -catenin. Taken together, our findings demonstrate that LEF1/TCF3 is necessary but not sufficient for TOPGAL activation, revealing the existence of positive and negative regulators of these factors in the skin. Furthermore, our findings unveil the importance of activated LEF/TCF complexes at distinct times in hair development and cycling when changes in cell fate and differentiation commitments take place.


Author(s):  
O. V. Matsneva ◽  
L. V. Tashmatova ◽  
T. M. Khromova ◽  
V. V. Shakhov

The purpose of this research is optimization of individual elements of micropropagation of promising introduced varieties of strawberry for use in the production system of healthy planting material. Objects of research are strawberry varieties of foreign selection Asia, Darselect, Siria, Florens, Klery, Honeyoye, Kimberly. The research was carried out in the laboratory of biotechnology of the FGBNU VNIISPK according to generally accepted methods. The optimal sterilizing agent for ensuring maximum sterility, maintaining high viability and rapid stabilization of the introduced strawberry material was 0.1% sulema solution. Elimination of the negative impact of oxidized phenols was achieved by transplanting to a fresh nutrient medium. Introduction into the culture in vitro with the activation of growth processes in strawberry rosettes after winter storage should be considered the most effective for the studied genotypes, which provides rapid stabilization of growth and reproduction, which is the determining factor of intensive production. Varieties of strawberries Asia (56.7%), Siria (52.9%), Florens (45.1%) were characterized by the largest number of explants capable of cloning after two months of cultivation, the least is the variety Klery (19.0%). The ability to form additional axillary micro-shoots was minimal when isolated in the active growth phase and the growth decay phase. The exception was the Asia variety, 33.2% of which explants formed additional microrosettes. The results obtained can be used for the development of systems for the production of healthy planting material of introduced varieties of garden strawberries using biotechnological approaches.


1924 ◽  
Vol 39 (2) ◽  
pp. 219-244 ◽  
Author(s):  
Oswald H. Robertson ◽  
Richard H. P. Sia

Somewhat discordant results which have been reported by others who have investigated the property of the whole blood of resistant animals to cause inhibition of growth or death of pneumococci have led us to investigate this matter and to develop a new technique in which the conditions as they are present in the animal body are more nearly imitated. The observations already made have rendered it probable that phagocytosis plays some rôle in any destructive power for pneumococcus which whole blood possesses. We have, therefore, employed mixtures of serum and leucocytes in our tests, since when blood is coagulated the conditions become highly artificial. Furthermore, in order to imitate more nearly the conditions in the circulating blood the mixtures have been constantly, though gently, agitated. For this purpose a specially devised apparatus has been employed. The mixtures of serum and leucocytes have been inoculated with varying numbers of pneumococci in the active growth phase and after varying intervals of time the tubes containing the mixtures of serum, leucocytes, and bacteria have been opened, examined microscopically, and cultures made. Employing this technique it has been found that the growth of pneumococci having low virulence for cats is markedly inhibited in mixtures of cat serum and cat leucocytes. It was impossible to recover pneumococci from the tubes showing no apparent growth, either when the contents were transplanted into various kinds of culture media, or when the contents were injected into mice of a variety highly susceptible to pneumococcus infection. 10,000 times the number of pneumococci sufficient ordinarily to kill a mouse failed to do so after a 24 hour sojourn in the cat serum-leucocyte mixture. Mixtures of dog serum and leucocytes exert a similar action. The serum and leucocytes of animals susceptible to pneumococcus infection (rabbits and guinea pigs,) on the other hand, failed to injure pneumococci even in extremely small quantities. These results indicate that the blood of resistant animals, at least of the dog and cat, possesses destructive properties for pneumococci, and that this destructive power is not possessed by the blood of certain susceptible animals. The experiments suggest that natural immunity depends chiefly, if not entirely, upon this property. The leucocytes play an active part in this process, but whether the destruction of the pneumococci occurs entirely within the leucocytes or not is not determined. That the serum also plays a part is shown by the fact that when the serum of resistant animals was inactivated before being used in the serum-leucocyte mixture, the growth of even very small numbers of pneumococci was not prevented. Further experiments with cat serum and leucocytes were carried out to determine the optimum rate and time of agitation, the amount of serum and leucocytes required, and also the period of incubation necessary for the inhibition of growth and death of the pneumococci to occur.


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