The relationship between erythropoietin-dependent cellular differentiation and colony-forming ability in prenatal haemopoietic tissues

Development ◽  
1975 ◽  
Vol 34 (3) ◽  
pp. 575-588
Author(s):  
R. J. Cole ◽  
T. Regan ◽  
S. L. White ◽  
E. M. Cheek

Levels of haem synthesis achieved by foetal liver erythroblasts responding to erythropoietin in vitro are similar in dissociated cell cultures and in cultures of organized tissues. Erythroid colony-forming cells reach maximum numbers on the sixteenth day of gestation. Their presence in foetal liver is associated with the period of most rapid production of erythrocytes, and with in vitro sensitivity to erythropoietin measured as enhanced haem synthesis. It is concluded that at least a proportion of erythroid colony-forming cells in the foetal liver are dependent on erythropoietin in situ and that these cells are separated from the earliest recognizable pro-erythroblast by 1–2 cell divisions. Populations of granulocyte-macrophage colony-forming cells change independently of erythroid colony-forming cell numbers.

1996 ◽  
Vol 44 (2) ◽  
pp. 103-110 ◽  
Author(s):  
J.W. Cone ◽  
A.H. Van Gelder ◽  
A.M. Van Vuuren

The amount of rumen fermentable organic matter (FOM) can be calculated using tables, taking into account the amount of digestible organic matter, the content of fat and fermentation products, and the amount of starch and protein escaping rumen fermentation, or FOM can be calculated using in situ incubations. An in vitro method is described to predict FOM using amylase and other carbohydrate degrading enzymes. FOM estimated by the enzymic method showed a moderate correlation (Rsuperscript 2 = 0.71) with FOM estimated by the in situ method. The relationship could be improved by separating the high crude fibre samples (Rsuperscript 2 = 0.88) from the other samples (Rsuperscript 2 = 0.77). Because degradation rates with the enzymic method were high compared with the assumed rumen passage rates, it proved that FOM could be predicted with a similar accuracy (Rsuperscript 2 = 0.76 - 0.80) by the undegraded fraction after 24 h.


2007 ◽  
Vol 2007 ◽  
pp. 210-210
Author(s):  
H. Paya ◽  
A. Taghizadeh ◽  
H. Janmohamadi ◽  
G.A Moghadam

Ration formulation systems require information on nutrient requirements of the animal and reliable values for rumen degradable and undegradable fractions of feed ingredients. The in situ nylon-bag technique is widely used to characterize the disappearance of feeds from the rumen (Woods et al., 2002). The objective of this study was determining of relationship between in vitro and in situ dry matter disappearance.


Reproduction ◽  
2017 ◽  
Vol 153 (1) ◽  
pp. 63-73 ◽  
Author(s):  
Chulin Yu ◽  
Meiling Li ◽  
Yue Wang ◽  
Ying Liu ◽  
Chengzhi Yan ◽  
...  

The corticotropin-releasing hormone (CRH) signaling system is involved in numbers of stress-related physiological and pathological responses, including its inhibiting effects on estradiol (E2) synthesis and follicular development in the ovary. In addition, there are reports that microRNAs (miRNAs) can control the function of animal reproductive system. The aim of present study was to investigate the functions of miR-375 and the relationship between miR-375 and CRH signaling molecules in the porcine ovary. First, our common PCR results show that miR-375 and the CRH receptor 1 (CRHR1) are expressed in porcine ovary, whereas CRH receptor 2 (CRHR2) is not detected. We further have located the cell types of miR-375 and CRHR1 by in situ hybridization (ISH), and the results show that miR-375 is located only in the granulosa cells, whereas CRHR1 is positive in all of granulosa cells and oocytes, inferring that miR-375 and CRHR1 are co-localized in granulosa cells. Second, we show that overexpression of miR-375 in cultured granulosa cells suppresses the E2 production, whereas miR-375 knockdown demonstrates the opposite result. Besides, our in vitro results demonstrate that miR-375 mediates the signaling pathway of CRH inhibiting E2 synthesis. Finally, our data show that the action of miR-375 is accomplished by directly binding to the 3′UTR of specificity protein1 (SP1) mRNA to decrease the SP1 protein level. Thus, we conclude that miR-375 is a key factor in regulating E2 synthesis by mediating the CRH signaling pathway.


1961 ◽  
Vol 37 (4) ◽  
pp. 516-528 ◽  
Author(s):  
E. Diczfalusy ◽  
O. Cassmer ◽  
C. Alonso ◽  
M. de Miquel ◽  
B. Westin

ABSTRACT In vitro and in vivo experiments were carried out in order to test a previously advanced hypothesis according to which the human foetus is capable of carrying out oestrogen conjugation reactions. In vitro incubation of slices of different foetal tissues with oestriol (oestra-1,3,5(10)-triene-3,16α,17β-triol) resulted in a significantly increased concentration of conjugated oestriol in foetal liver, lungs, kidneys, adrenals, and perhaps also in skeletal muscle. No such increase was found when endometrial or myometrial tissue from an adult subject was incubated under the same experimental conditions, or when foetal tissues were incubated in the absence of oestriol. Countercurrent distribution studies of the conjugated material formed in vitro suggest that it might be identical with oestriol Intra-amniotic injection of 17β-estradiol ((oestra-1,3,5(10))-triene-3,17βdiol) or oestriol to volunteers in whom the foetus was previously separated in situ from its placental connections resulted in a significantly elevated concentration of conjugated oestrone ((3-hydroxy-oestra-1,3,5(10)-trien17-one). 17β-oestradiol and oestriol, respectively, in the foetal lungs and livers and – following 17β administration – also in the intestines. On the other hand, the concentration of conjugated oestrone, 17β-oestradiol or oestriol in the placental tissue was significantly lower under these conditions than in similarly treated patients with an intact foeto-placental connection. When previable foetuses were perfused with diluted blood to which 17β-oestradiol, or oestriol was added, a significantly elevated concentration of conjugated oestrone + 17β-oestradiol, and oestriol, respectively, was found in the foetal lungs, liver, intestines, kidneys + adrenals. It is concluded that the human foetus is already an important site of oestrogen conjugation at relatively early stages of gestation. It is suggested that these conjugation processes take place in several foetal organs, such as the lungs, liver, kidneys, adrenals, intestines, and perhaps also other tissues.


Diabetes ◽  
2007 ◽  
Vol 57 (3) ◽  
pp. 724-731 ◽  
Author(s):  
David A. Ingram ◽  
Izlin Z. Lien ◽  
Laura E. Mead ◽  
Myka Estes ◽  
Daniel N. Prater ◽  
...  

Development ◽  
1981 ◽  
Vol 62 (1) ◽  
pp. 37-46
Author(s):  
Sheila R. Weinberg ◽  
Emmeline G. McCarthy ◽  
Thomas J. MacVittie

The influence of in utero low-dose ionizing radiation exposure on murine hemopoietic embryogenesis was investigated. In vitro assays such as micro plasma-clot cultures and double-layer soft agar cultures served as sensitive biodosimeters to determine erythropoietic and granulopoietic injuries. Day-10·5, HA/ICR, pregnant mice were irradiated with 0, 50, 100, 150,200, or 300 rads, and day-14·5 fetal livers were studied for colony-forming unit-erythroid (CFU-E), buist-forming unit-erythroid (BFU-E), granulocyte-macrophage colony-forming cell (GM-CFC), and macrophage-colony-forming cell (M-CFC) activity. Fetuses subjected to doses of 200 rads or higher on day 10·5 of gestation responded with a decrease in day-14·5 liver cellularity, reflecting injury to the developing organ and its inability to recover to the nonirradiated values. Difference in response between erythropoietin(EPO)-dependent and EPO-independent CFU-E strongly suggests existence of two populations of erythroid progenitor cells with different radiosensitivities. A dose of 200 rads markedly reduced CFUE recovery, and a dose of 100 rads was sufficient to reduce BFU-E recovery to almost 10% of 0-rad values. Nonirradiated day-14·5 fetal liver had more GM-CFC compared to any of the irradiated fetuses, and a dramatically reduced M-CFC recovery occurred with each increase in dose following 150 rads. Our results showed that (1) fetal liver granulopoiesis is more sensitive to radiation injury compared to erythropoiesis, and (2) fetal liver has a greater potential for erythropoiesis recovery.


2020 ◽  
Vol 8 (1) ◽  
pp. e000649
Author(s):  
Tonke K Raaijmakers ◽  
Renske J E van den Bijgaart ◽  
Martijn H den Brok ◽  
Melissa Wassink ◽  
Annemarie de Graaf ◽  
...  

BackgroundTumor ablation techniques, like cryoablation, are successfully used in the clinic to treat tumors. The tumor debris remaining in situ after ablation is a major antigen depot, including neoantigens, which are presented by dendritic cells (DCs) in the draining lymph nodes to induce tumor-specific CD8+T cells. We have previously shown that co-administration of adjuvants is essential to evoke strong in vivo antitumor immunity and the induction of long-term memory. However, which adjuvants most effectively combine with in situ tumor ablation remains unclear.Methods and resultsHere, we show that simultaneous administration of cytidyl guanosyl (CpG) with saponin-based adjuvants following cryoablation affects multifunctional T-cell numbers and interleukin (IL)-1 induced polymorphonuclear neutrophil recruitment in the tumor draining lymph nodes, relative to either adjuvant alone. The combination of CpG and saponin-based adjuvants induces potent DC maturation (mainly CpG-mediated), antigen cross-presentation (mainly saponin-based adjuvant mediated), while excretion of IL-1β by DCs in vitro depends on the presence of both adjuvants. Most strikingly, CpG/saponin-based adjuvant exposed DCs potentiate antigen-specific T-cell proliferation resulting in multipotent T cells with increased capacity to produce interferon (IFN)γ, IL-2 and tumor necrosis factor-α in vitro. Also in vivo the CpG/saponin-based adjuvant combination plus cryoablation increased the numbers of tumor-specific CD8+T cells showing enhanced IFNγ production as compared with single adjuvant treatments.ConclusionsCollectively, these data indicate that co-injection of CpG with saponin-based adjuvants after cryoablation induces an increased amount of tumor-specific multifunctional T cells. The combination of saponin-based adjuvants with toll-like receptor 9 adjuvant CpG in a cryoablative setting therefore represents a promising in situ vaccination strategy.


1996 ◽  
Vol 1996 ◽  
pp. 227-227 ◽  
Author(s):  
A.H. Murray ◽  
D. Daalkhaijav ◽  
C.D. Wood

In Mongolia animal performance is very much dependent on the quality and quantity of natural grassland available, since certain pastoral animals may obtain as much as 98% of their annual intake from pasture. There have been few studies to date on either in vivo or in vitro degradation of native Mongolian pastures. This paper seeks to investigate the degradation characteristics of native pastures from 2 regions in Mongolia, high mountain and forest steppe. It also investigates the relationship between the in vitro gas production technique and the in sacco technique.


2017 ◽  
Vol 13 (3) ◽  
pp. 20160928 ◽  
Author(s):  
Weng Ngai Lam ◽  
Kwek Yan Chong ◽  
Ganesh S. Anand ◽  
Hugh Tiang Wah Tan

The fluid-containing traps of Nepenthes carnivorous pitcher plants (Nepenthaceae) are often inhabited by organisms known as inquilines. Dipteran larvae are key components of such communities and are thought to facilitate pitcher nitrogen sequestration by converting prey protein into inorganic nitrogen, although this has never been demonstrated in Nepenthes . Pitcher fluids are also inhabited by microbes, although the relationship(s) between these and the plant is still unclear. In this study, we examined the hypothesis of digestive mutualism between N. gracilis pitchers and both dipteran larvae and fluid microbes. Using dipteran larvae, prey and fluid volumes mimicking in situ pitcher conditions, we conducted in vitro experiments and measured changes in available fluid nitrogen in response to dipteran larvae and microbe presence. We showed that the presence of dipteran larvae resulted in significantly higher and faster releases of ammonium and soluble protein into fluids in artificial pitchers, and that the presence of fluid microbes did likewise for ammonium. We showed also that niche segregation occurs between phorid and culicid larvae, with the former fragmenting prey carcasses and the latter suppressing fluid microbe levels. These results clarify the relationships between several key pitcher-dwelling organisms, and show that pitcher communities facilitate nutrient sequestration in their host.


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