scholarly journals Evidence that chemical signals promote fighting between intact male hooded rats

1981 ◽  
Vol 17 (3) ◽  
pp. 156-158
Author(s):  
Barry Fass ◽  
J. Russell Mason ◽  
David A. Stevens
Keyword(s):  

1980 ◽  
Vol 25 (10) ◽  
pp. 848-848
Author(s):  
DONALD A. DEWSBURY


Nature ◽  
2016 ◽  
Author(s):  
Sara Reardon
Keyword(s):  


1981 ◽  
Vol 96 (2) ◽  
pp. 273-280 ◽  
Author(s):  
Mridula Chowdhury ◽  
Robert Tcholakian ◽  
Emil Steinberger

Abstract. It has been suggested that treatment of intact male rats with oestradiol benzoate (OeB) causes an interference with testosterone (T) production by the testes by a direct inhibitory effect on steroidogenesis. To test this hypothesis, different doses (5, 10 or 25 IU) of hCG were administered concomitantly with 50 μg of OeB to adult intact or hypophysectomized male rats. The testicular and plasma testosterone, and serum hCG levels were determined. The sex accessory weights were recorded. In the intact OeB-treated group of animals, hCG stimulated both the secondary sex organs and plasma testosterone levels above the intact control group. However, in hypophysectomized animals, although plasma testosterone levels increased above that of intact controls, their secondary sex organ weights did not. Moreover, inspite of high circulating hCG levels, the testicular testosterone content and concentration remained suppressed in OeB-treated animals. The reason for such dichotomy of hCG action on OeB-treated animals is not clear at present.



2018 ◽  
Vol 239 (3) ◽  
pp. 303-312 ◽  
Author(s):  
H H Farman ◽  
K L Gustafsson ◽  
P Henning ◽  
L Grahnemo ◽  
V Lionikaite ◽  
...  

The importance of estrogen receptor α (ERα) for the regulation of bone mass in males is well established. ERα mediates estrogenic effects both via nuclear and membrane-initiated ERα (mERα) signaling. The role of mERα signaling for the effects of estrogen on bone in male mice is unknown. To investigate the role of mERα signaling, we have used mice (Nuclear-Only-ER; NOER) with a point mutation (C451A), which results in inhibited trafficking of ERα to the plasma membrane. Gonadal-intact male NOER mice had a significantly decreased total body areal bone mineral density (aBMD) compared to WT littermates at 3, 6 and 9 months of age as measured by dual-energy X-ray absorptiometry (DEXA). High-resolution microcomputed tomography (µCT) analysis of tibia in 3-month-old males demonstrated a decrease in cortical and trabecular thickness in NOER mice compared to WT littermates. As expected, estradiol (E2) treatment of orchidectomized (ORX) WT mice increased total body aBMD, trabecular BV/TV and cortical thickness in tibia compared to placebo treatment. E2 treatment increased these skeletal parameters also in ORX NOER mice. However, the estrogenic responses were significantly decreased in ORX NOER mice compared with ORX WT mice. In conclusion, mERα is essential for normal estrogen signaling in both trabecular and cortical bone in male mice. Increased knowledge of estrogen signaling mechanisms in the regulation of the male skeleton may aid in the development of new treatment options for male osteoporosis.



2017 ◽  
Vol 95 (6) ◽  
pp. 2345
Author(s):  
C. L. Puls ◽  
A. Rojo ◽  
P. D. Matzat ◽  
A. L. Schroeder ◽  
M. Ellis
Keyword(s):  


2019 ◽  
Author(s):  
Derrick Roberts ◽  
Ben S. Pilgrim ◽  
Tristan Dell ◽  
Molly Stevens

We describe the first report of a self-immolation cascade that can be reversibly paused and reactivated in response to pH changes. This system employs a triazole-based self-immolative linker, which expresses a pH-sensitive intermediate during its elimination sequence. This allows the system to respond to pH cues within its local environment, thus establishing a new way to gate self-immolative release using fluctuating or transient chemical signals.<br>



2020 ◽  
Vol 16 (4) ◽  
pp. 404-412 ◽  
Author(s):  
Ihab Alnajim ◽  
Manjree Agarwal ◽  
Tao Liu ◽  
YongLin Ren

Background: The red flour beetle, Tribolium castaneum (Herbst) (Coleoptera: Tenebrionidae) is one of the world’s most serious stored grain insect pests. A method of early and rapid identification of red flour beetle in stored products is urgently required to improve control options. Specific chemical signals identified as Volatile Organic Compounds (VOCs) that are released by the beetle can serve as biomarkers. Methods: The Headspace Solid Phase Microextraction (HS-SPME) technique and the analytical conditions with GC and GCMS were optimised and validated for the determination of VOCs released from T. castaneum. Results: The 50/30 μm DVB/CAR/PDMS SPME fibre was selected for extraction of VOCs from T. castaneum. The efficiency of extraction of VOCs was significantly affected by the extraction time, temperature, insect density and type of SPME fibre. Twenty-three VOCs were extracted from insects in 4 mL flask at 35 ± 1°C for four hours of extraction and separated and identified with gas chromatography-mass spectroscopy. The major VOCs or chemical signals from T. castaneum were 1-pentadecene, p-Benzoquinone, 2-methyl- and p-Benzoquinone, 2-ethyl. Conclusion: This study showed that HS-SPME GC technology is a robust and cost-effective method for extraction and identification of the unique VOCs produced by T. castaneum. Therefore, this technology could lead to a new approach in the timely detection of T. castaneum and its subsequent treatment.





Ethology ◽  
2020 ◽  
Author(s):  
Christian Cely Ortiz ◽  
Elizabeth A. Tibbetts


Sign in / Sign up

Export Citation Format

Share Document