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42.
Soil samples taken from the Valley of Flowers, a component of the Nanda Devi Biosphere Reserve in the Himalayan regions of
India showed the presence of twenty two free living species of ciliates. There is a preponderance of species which exhibit
oral ciliature and ontogenesis in the Gonostomum pattern. Of the four species of the genus Gonostomum, three viz., G affine, G gonostomoida and G kuehnelti are similar to described species; Gonostomum singhii is new. The two species of genus Paragonostomum viz., P minuta and P ghangriai are new. The three new species are described in the present paper. All these species show prominent hypertrophied ciliary
structures. Their paroral membranes reveal characteristic differences with respect to their position, number of constituent
cilia and the distance between adjacent cilia. It is proposed that such species specific features of the paroral membrane
have a bearing in exercising different food organism preferences as they co-exist at many sites. This single factor has possibly
played an important role in species diversification of this group of hypotrichs in this isolated habitat. 相似文献
43.
AbstractMigration is a biologically distinct and unique phenomenon that enables the birds to migrate twice-a-year between the breeding and wintering grounds. These movements are known as spring and autumn migration, respectively. Depending on their inherent programming, the migratory birds may fly during day or night or both. Different environmental factors such as, temperature, food, predator pressure and physiological demands of energy storage and expenditure, contribute to the pattern of migrations, day or nighttime. Since, most of them are nighttime migrants they have to make dramatic changes in their physiology and behavior to transform them from being diurnal to predominantly nocturnal. These changes result in different life history stages (LHSs) such as migration, reproduction and molt, in their annual cycle, which are regulated by endogenous circadian and circannual clocks. As a result, the birds start preparing well in advance for the approaching LHS. The present review focuses on behavioral strategies of a nocturnal migrant and understanding of the possible physiological responses to ensure successful migration. 相似文献
44.
Sherin Kaul L. Sai Keerthana Pankaj Kumar Komal Birader Yathirajarao Tammineni Deepali Rawat Pankaj Suman 《PLoS neglected tropical diseases》2021,15(10)
Development of a rapid, on-site detection tool for snakebite is highly sought after, owing to its clinically and forensically relevant medicolegal significance. Polyvalent antivenom therapy in the management of such envenomation cases is finite due to its poor venom neutralization capabilities as well as diagnostic ramifications manifested as untoward immunological reactions. For precise molecular diagnosis of elapid venoms of the big four snakes, we have developed a lateral flow kit using a monoclonal antibody (AB1; IgG1 – κ chain; Kd: 31 nM) generated against recombinant cytotoxin-7 (rCTX-7; 7.7 kDa) protein of the elapid venom. The monoclonal antibody specifically detected the venoms of Naja naja (p < 0.0001) and Bungarus caeruleus (p<0.0001), without showing any immunoreactivity against the viperidae snakes in big four venomous snakes. The kit developed attained the limit of quantitation of 170 pg/μL and 2.1 ng/μL in spiked buffer samples and 28.7 ng/μL and 110 ng/μL in spiked serum samples for detection of N. naja and B. caeruleus venoms, respectively. This kit holds enormous potential in identification of elapid venom of the big four snakes for effective prognosis of an envenomation; as per the existing medical guidelines. 相似文献
45.
Graham A. McCulloch Komal Gurdasani James P. Hereward Louise Morin Gimme H. Walter S. Raghu 《Diversity & distributions》2023,29(7):879-891
Aim
We investigated the invasion history of Lycium ferocissimum, a spine-covered shrub native to South Africa that was introduced to Australia in the mid-1800s, and has since developed into a damaging invasive plant of undisturbed landscapes and pastures. In addition to identifying the provenance of the Australian plants, we tested for evidence of admixture, and contrasted genetic diversity and structuring across the native and introduced ranges.Location
Samples were collected across South Africa (24 localities) and Australia (26 localities).Methods
We used genotyping-by-sequencing (3117 SNPs across 381 individuals) to assess population genetic structuring in L. ferocissimum across Australia and South Africa. Coalescent analyses were used to explicitly test contrasting invasion scenarios.Results
Clear geographic genetic structuring was detected across South Africa, with distinct clusters in the Eastern and Western Cape provinces. The L. ferocissimum plants in Australia form their own genetic cluster, with a similar level of genetic diversity as plants in South Africa. Coalescent analyses demonstrated that the lineage in Australia was formed by admixture between Eastern Cape and Western Cape plants, with most of the genetic material from the Australian lineage originating from the Western Cape. Our analyses suggest that L. ferocissimum plants were originally introduced to South Australia, though it is unclear whether admixture occurred before or after its introduction to Australia. We detected little evidence of geographic genetic structure across Australia, although many of the populations were genetically distinct from one another.Main Conclusions
Our results illustrate how admixture can result in genetically diverse and distinct invasive populations. The complex invasion history of L. ferocissimum in Australia poses particular challenges for biological control. We suggest potential biological control agents should be screened against admixed plants (in addition to plants from the Eastern and Western Cape) to test whether they provide effective control of the genetically distinct invasive lineage. 相似文献46.
Kobra Bahrampour Juybari Komal Rizwan Sanaz Faramarz Asie Sadeghi Arian Amirkhosravi Mohammad Hadi Nematollahi Mehrnaz Mehrabani 《化学与生物多样性》2023,20(4):e202200721
During stem cell therapy, some issues, such as obscure fate of stem cells or their low survival rate in the body, should be addressed to boost their therapeutic efficiency. Nanotechnology offers a suitable solution to combat such limitations. Carbon quantum dots (CQDs) are carbon-based nanomaterials and may be used as multi-purpose compounds in stem cell therapy. CQDs are excellent choices for stem cell labeling thanks to their special features such as optical properties and good biocompatibility. Besides, they can modulate the biological function of stem cells, such as their proliferation, homing ability, and differentiation properties. Considering the charismatic feature of CQDs and their broad unique effect on stem cells, the current review aims to summarize the most advancements in this field. Hence, we first focused on CQDs synthesis and their applications. In the next section, the stem cell categories will be discussed, and the final part is dedicated to the recent research evaluating the impact of CQDs on stem cell therapy. 相似文献
47.
The virus causing mosaic of muskmelon in the Punjab is transmitted through seed, sap and aphids but not through beetle, whitefly, fungi or contact. It systemically infected Nicotiana tabacum (var. “White Burley” and CTRI-Special), N. glutinosa, N. rustica and Capsicum annuum besides various cucurbit hosts when inoculated mechanically. The virus gave positive reaction with the antiserum of cucumber mosaic virus and the particles are spherical in shape. The virus has been identified as a distinct strain of cucumber mosaic virus and is designated as muskmelon strain of cucumber mosaic virus (CMV-mst.). 相似文献
48.
Protection against β‐amyloid neurotoxicity by a non‐toxic endogenous N‐terminal β‐amyloid fragment and its active hexapeptide core sequence
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Komal Arora Ruth Taketa Tessi Sherrin Cedomir Todorovic James L. M. Lawrence Gene T. Yoshikawa Ho‐Leung Ng Victor J. Hruby Robert A. Nichols 《Journal of neurochemistry》2018,144(2):201-217
49.
Victor Babich Komal Vadnagara Francesca Di Sole 《Journal of cellular physiology》2019,234(8):13917-13930
A high renal oxygen (O2) need is primarily associated with the renal tubular O2 consumption (VO2) necessary for a high rate of sodium (Na+) transport. Limited O2 availability leads to increased levels of adenosine, which regulates the kidney via activation of both A1 and A2A adenosine receptors (A1R and A2AR, respectively). The relative contributions of A1R and A2AR to the regulation of renal Na+ transport and VO2 have not been determined. We demonstrated that A1R activation has a dose-dependent biphasic effect on both renal Na+/H+ exchanger-3 (NHE3), a major player in Na+ transport, and VO2. Here, we report concentration-dependent effects of adenosine: less than 5 × 10−7 M adenosine-stimulated NHE3 activity; between 5 × 10−7 M and 10−5 M adenosine-inhibited NHE3 activity; and greater than 10−5 M adenosine reversed the change in NHE3 activity (returned to baseline). A1R activation mediated the activation and inhibition of NHE3 activity, whereas 10−4 M adenosine had no effect on the NHE3 activity due to A2AR activation. The following occurred when A1R and A2AR were activated: (a) Blockade of the A2AR receptor restored the NHE3 inhibition mediated by A1R activation, (b) the NHE-dependent effect on VO2 mediated by A1R activation became NHE independent, and (c) A2AR bound to A1R. In summary, A1R affects VO2 via NHE-dependent mechanisms, whereas A2AR acts via NHE-independent mechanisms. When both A1R and A2AR are activated, the A2AR effect on NHE3 and VO2 predominates, possibly via an A1R–A2AR protein interaction. A2AR–A1R heterodimerization is proposed as the molecular mechanism enabling the NHE-independent control of renal VO2. 相似文献
50.
BACKGROUND AND AIMS: Determining the mode of action of allelochemicals is one of the challenging aspects in allelopathic studies. Recently, allelochemicals have been proposed to cause oxidative stress in target tissue and induce an antioxidant mechanism. alpha-Pinene, one of the common monoterpenoids emitted from several aromatic plants including forest trees, is known for its growth-inhibitory activity. However, its mechanism of action remains unexplored. The aim of the present study was to determine the inhibitory effect of alpha-pinene on root growth and generation of reactive oxygen species, as indicators of oxidative stress and changes in activities of antioxidant enzymes. METHODS: Effects of alpha-pinene on early root growth were studied in five test species, Cassia occidentalis, Amaranthus viridis, Triticum aestivum, Pisum sativum and Cicer arietinum. Electrolyte leakage, lipid peroxidation, hydrogen peroxide generation, proline accumulation, and activities of the enzymes superoxide dismutase (SOD), ascorbate peroxidase (APX), guaiacol peroxidase (GPX), catalase (CAT) and glutathione reductase (GR) were studied in roots of C. occidentalis. KEY RESULTS: alpha-Pinene inhibited the radicle growth of all the test species. Exposure of C. occidentalis roots to alpha-pinene enhanced solute leakage, and increased levels of malondialdehyde, proline and hydrogen peroxide, indicating lipid peroxidation and induction of oxidative stress. Activities of the antioxidant enzymes SOD, CAT, GPX, APX and GR were significantly elevated, thereby indicating the enhanced generation of reactive oxygen species (ROS) upon alpha-pinene exposure. Increased levels of scavenging enzymes indicates their induction as a secondary defence mechanism in response to alpha-pinene. CONCLUSIONS: It is concluded that alpha-pinene inhibits early root growth and causes oxidative damage in root tissue through enhanced generation of ROS, as indicated by increased lipid peroxidation, disruption of membrane integrity and elevated antioxidant enzyme levels. 相似文献