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Michael A. Huffman Raveendra Kumara Yoshi Kawamoto Prasad M. Jayaweera Massimo Bardi Charmalie A. D. Nahallage 《American journal of primatology》2020,82(3):e23113
Allen's rule (1877) predicts ecogeographical anatomical variation in appendage proportions as a function of body temperature regulation. This phenomenon has been tested in a variety of animal species. In macaques, relative tail length (RTL) is one of the most frequently measured appendages to test Allen's rule. These studies have relied on museum specimens or the invasive and time-consuming capturing of free-ranging individuals. To augment sample size and lessen these logistical limitations, we designed and validated a novel noninvasive technique using digitalized photographs processed using LibreCAD, an open-source 2D-computer-aided design (CAD) application. This was used to generate pixelated measurements to calculate an RTL equivalent, the Tail to Trunk Index (TTI) = (tail [tail base to anterior tip] pixel count/trunk [neck to tail base] pixel count). The TTI of 259 adult free-ranging toque macaques (Macaca sinica) from 36 locations between 7 and 2,087 m above sea level (m.a.s.l.) was used in the analysis. Samples were collected from all three putative subspecies (M. s. sinica, aurifrons, and opisthomelas), at locations representing all altitudinal climatic zones where they are naturally distributed. These data were used to test whether toque macaque tail length variation across elevation follows Allen's rule, predicting that RTL decreases with increasing elevation and lower temperature. Our results strongly supported this prediction. There was also a statistically significant, negative correlation between elevation and annual average temperature. The best predictor for the TTI index was elevation. Significant subspecies differences in RTL are linked in part to their ecological and altitudinal niche separation, but overall the variation is seen as the species' adaptation to climate. The method developed for the quick morphometric assessment of relative body proportions, applicable for use on unhabituated free-ranging animals, widens the range of materials available for research studying morphological characteristics and their evolution in primates. 相似文献
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We assessed the distribution and conservation status of bonnet macaques (Macaca radiata), rhesus macaques (Macaca mulatta) and Hanuman langurs (Semnopithecus entellus) in the state of Karnataka, India. Karnataka is situated in southwest India with an area of 191,791 km2. A total of 9697 km of vehicular survey was made from November 2001 to July 2004. We also visited 107 temples/tourist spots
to determine the presence of primates. Bonnet macaques and Hanuman langurs were widely distributed, whereas rhesus macaques
were not found in the state. However, bonnet macaques were absent in a few districts in the northern plains and Hanuman langurs
were absent in some districts of the southern plains. A total of 205 groups of bonnet macaques and 139 groups of Hanuman langurs
were sighted. The relative encounter rate of both species differed across biogeographic zones. Bonnet macaques were largely
encountered in the Western Ghats and the Southern Plateau whereas Hanuman langurs were abundant in the Western Ghats and Northern
Plains. We found that bonnet macaques have been eliminated from about 48% temples/tourist spots where they occurred in the
recent past. The Hanuman langur population of Dharwar–Haliyal Road was assessed during April 2003, and we found that the present
population size was about 38% of a previous survey in 1961. Habitat change, hunting/trapping and translocation were the major
factors causing a decline in the langur population. 相似文献
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Mohana Kumara P Zuehlke S Priti V Ramesha BT Shweta S Ravikanth G Vasudeva R Santhoshkumar TR Spiteller M Uma Shaanker R 《Antonie van Leeuwenhoek》2012,101(2):323-329
Rohitukine is a chromane alkaloid possessing anti-inflammatory, anti-cancer and immuno-modulatory properties. The compound
was first reported from Amoora rohituka (Meliaceae) and later from Dysoxylum binectariferum (Meliaceae) and Schumanniophyton problematicum (Rubiaceae). Flavopiridol, a semi-synthetic derivative of rohitukine is a potent CDK inhibitor and is currently in Phase
III clinical trials. In this study, the isolation of an endophytic fungus, Fusarium proliferatum (MTCC 9690) from the inner bark tissue of Dysoxylum binectariferum Hook.f (Meliaceae) is reported. The endophytic fungus produces rohitukine when cultured in shake flasks containing potato
dextrose broth. The yield of rohitukine was 186 μg/100 g dry mycelial weight, substantially lower than that produced by the
host tissue. The compound from the fungus was authenticated by comparing the LC–HRMS and LC–HRMS/MS spectra with those of
the reference standard and that produced by the host plant. Methanolic extract of the fungus was cytotoxic against HCT-116
and MCF-7 human cancer cell lines (IC50 = 10 μg/ml for both cancer cell lines). 相似文献
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Barrese AA Genis C Fisher SZ Orwenyo JN Kumara MT Dutta SK Phillips E Kiddle JJ Tu C Silverman DN Govindasamy L Agbandje-McKenna M McKenna R Tripp BC 《Biochemistry》2008,47(10):3174-3184
This paper examines the functional mechanism of thioxolone, a compound recently identified as a weak inhibitor of human carbonic anhydrase II by Iyer et al. (2006) J. Biomol. Screening 11, 782-791 . Thioxolone lacks sulfonamide, sulfamate, or hydroxamate functional groups that are typically found in therapeutic carbonic anhydrase (CA) inhibitors, such as acetazolamide. Analytical chemistry and biochemical methods were used to investigate the fate of thioxolone upon binding to CA II, including Michaelis-Menten kinetics of 4-nitrophenyl acetate esterase cleavage, liquid chromatography-mass spectrometry (LC-MS), oxygen-18 isotope exchange studies, and X-ray crystallography. Thioxolone is proposed to be a prodrug inhibitor that is cleaved via a CA II zinc-hydroxide mechanism known to catalyze the hydrolysis of esters. When thioxolone binds in the active site of CA II, it is cleaved and forms 4-mercaptobenzene-1,3-diol via the intermediate S-(2,4-thiophenyl)hydrogen thiocarbonate. The esterase cleavage product binds to the zinc active site via the thiol group and is therefore the active CA inhibitor, while the intermediate is located at the rim of the active-site cavity. The time-dependence of this inhibition reaction was investigated in detail. Because this type of prodrug inhibitor mechanism depends on cleavage of ester bonds, this class of inhibitors may have advantages over sulfonamides in determining isozyme specificity. A preliminary structure-activity relationship study with a series of structural analogues of thioxolone yielded similar estimates of inhibition constants for most compounds, although two compounds with bromine groups at the C1 carbon of thioxolone were not inhibitory, suggesting a possible steric effect. 相似文献