161 research outputs found
Solanum americanum var. odishensis Kalidass & P. Murugan 2016, var. nov.
No full textSolanum americanum Mill. var. odishensis Kalidass & P. Murugan, var. nov. (Fig. 1). Diagnosis: Solanum americanum var. odishensis is closely allied to Solanum americanum Mill., but differs from it in having prickly angular stem, inflorescence 5-8 flowered, style erect, densely villous in middle and curved at apex. Type: INDIA, Odisha: Kandhamal District, G. Udayagiri Forest range, 14 July 2015, 20˚07'204''N, 084˚22'187''E, ± 658m, Kalidass & Murugan 18021 (Holotype: CAL!, Isotypes: MH!, RPRC!). Erect annual herbs, 100-130 cm high. Stem 4-angular with prickles, branched, pubescentglabrescent; branches ascending. Leaves simple, alternate or sub-opposite, ovate or ovatelanceolate, 4-9×3-5 cm, cuneate or obtuse at base, margin entire to sinuate or sinuate-dentate, acute or acuminate at apex, pale beneath, glabrous or pubescent on both surfaces; lateral nerves 4- 6 pairs; petioles 2-3 cm long, flat or terete. Inflorescence axillary or extra-axillary, umbellate or sub-umbellate cymes, 5-8 flowered. Flowers 3-5 mm long, creamy white; peduncle 2-3 cm long, slender, glabrous or pubescent; pedicels 8-10 mm long, slender, glabrous. Calyx 5-lobed, valvate,1.5 mm in diameter, base united; calyx-lobes deltoid, each lobe less than 1 mm long, green, pubescent, margin ciliate, reflexed away from mature berries, persistent. Corolla valvate, 5- lobed, 2-3 mm in diameter, star-like, base united; lobes ovate or lanceolate 2.5 mm long, reflexed, margin ciliate. Stamens 5, epipetalous; anthers lanceolate, 1 mm long, yellow, dithecus, basifixed and dehisces apically; filament c. 0.5 mm long, glabrous. Ovary globose, c. 0.8 mm long, glabrous; style less than 1.5 mm long, filiform, densely villous in the middle, curved at apex; stigma capitate, green. Berries globose, 5-8 mm in diameter black or dull black when ripe, glossy. Seeds 10-30, ovate or orbicular, 1.0-1.5 mm long, brownish-white, compressed. Flowering and fruiting: May - September. 1 Corresponding author. Email: [email protected] Etymology: Solanum americanum var. odishensis is named after the state Odisha, one of plant diversity zones in Eastern Ghats, India. Distribution: The new variety in distributed in the Odisha state of India as an Eastern Ghats element. Habitat: Solanum americanum var. odishensis is found to grow in open scrub forest, usually near water courses and shady localities. It grows along with Lantana camara L., Sida acuta Burm. f., Sesamum indicum L., Solanum torvum Sw., Albizia lebbeck (L.) Benth., Neolamarckia cadamba (Roxb.) Bosser. Paratypes: INDIA, Odisha state, Kandhamal District, Paburia, 20˚09'308''N, 084˚15'339''E and Alt. ±681 MSL; 14.07.2015, Kalidass & Murugan 18024 (RPRC) Kalinga Ghat, 20˚09'867''N, 084˚24'870''E and Alt. ±737 MSL; 15.07.2015, Kalidass & Murugan 18027 (RPRC) Ganjam District, Sikulipadara, 19˚24'086''N, 084˚20'372''E and Alt. ±594 MSL; 19.08.2015, Kalidass & Murugan 18045 (RPRC) Gajapati District, Parlakhemundi, Jajpur, 18˚47'630''N 084˚07'230''E and Alt. ±71 MSL; 21.08.2015, Kalidass & Murugan 18067 (RPRC) Ganjam District, Taptapani, 19˚29'126''N, 084˚23'660''E and Alt. ±439 MSL; 22.08.2015, Kalidass & Murugan 18087 (RPRC).Published as part of Plant Taxon, Bangladesh J., Murugan, P., Kalidass, C. & Panda, P. C., 2016, A New Variety Of Solanum Americanum Mill. (Solanaceae), From Eastern Ghats, India, pp. 83-85 in Bangladesh Journal of Plant Taxononomy 23 (1) on pages 83-85, DOI: 10.3329/bjpt.v23i1.28350, http://zenodo.org/record/633079
Sialic Acid Receptors: The Key to Solving the Enigma of Zoonotic Virus Spillover
No full textEmerging viral diseases are a major threat to global health, and nearly two-thirds of emerging human infectious diseases are zoonotic. Most of the human epidemics and pandemics were caused by the spillover of viruses from wild mammals. Viruses that infect humans and a wide range of animals have historically caused devastating epidemics and pandemics. An in-depth understanding of the mechanisms of viral emergence and zoonotic spillover is still lacking. Receptors are major determinants of host susceptibility to viruses. Animal species sharing host cell receptors that support the binding of multiple viruses can play a key role in virus spillover and the emergence of novel viruses and their variants. Sialic acids (SAs), which are linked to glycoproteins and ganglioside serve as receptors for several human and animal viruses. In particular, influenza and coronaviruses, which represent two of the most important zoonotic threats, use SAs as cellular entry receptors. This is a comprehensive review of our current knowledge of SA receptor distribution among animal species and the range of viruses that use SAs as receptors. SA receptor tropism and the predicted natural susceptibility to viruses can inform targeted surveillance of domestic and wild animals to prevent the future emergence of zoonotic viruses.This article is published as Kuchipudi, Suresh V., Rahul K. Nelli, Abhinay Gontu, Rashmi Satyakumar, Meera Surendran Nair, and Murugan Subbiah. "Sialic acid receptors: the key to solving the enigma of zoonotic virus spillover." Viruses 13, no. 2 (2021): 262. doi: https://doi.org/10.3390/v13020262
A panoramic view of motherhood by juxtaposing the select trilogies of Flora Nwapa and Perumal Murugan
No full text<p>This article by Vimala Johnshi Rani compares the portrayal of motherhood in the works of African writer Flora Nwapa and Indian writer Perumal Murugan. By examining trilogies by each author, Rani explores how women in post-colonial South Africa and India navigate societal expectations and personal desires.</p>
Factors involved in the proliferation of blaCMY-2 plasmid-bearing Escherichia coli in cattle
No full textThesis (Ph.D.), College of Veterinary Medicine, Washington State UniversityThird-generation cephalosporins are a crucial component of the antibiotic arsenal for human and veterinary medicine. Resistance to third-generation cephalosporins is often conveyed by blaCMY-2 plasmids. The prevalence of blaCMY-2 plasmid-bearing Salmonella and Escherichia coli and ceftiofur (third-generation cephalosporin) use in livestock has been implicated in this process. Nevertheless, injection of ceftiofur results in limited effect on the enteric flora and the majority of drug excreted in the urine. We employed a series of in vitro and in vivo passage studies showing that blaCMY-2 plasmids impose a fitness cost on their bacterial host and this cost is not mitigated by conjugation or segregation systems (Chapter I). Thus, selection is required to maintain blaCMY-2 plasmids in a population. After administration to cattle ceftiofur is quickly converted in to pharmacologically active ceftiofur metabolite (CFM). Because most (~ 70%) CFM is excreted through urine, we hypothesized that selection for cefR E. coli occurs primarily ex vivo rather than in vivo. We first found that when mixed in soil ceftiofur remains bioavailable but some antibiotics (e.g. tetracycline) are not (Chapter II). To further evaluate the fate of CFM ex vivo, we used matrices consisting of soil and feces with urine containing CFM and examined the factors that impact the longevity of CFM. Our findings showed that CFM remains bioavailable in soil for a longer period with higher concentration (as expected) and at colder temperatures. CFM bioavailability is retained much longer in autoclaved soil indicating that the soil microflora is probably responsible for eventual degradation of CFM. Importantly, our findings show that CFM confers a significant numerical (1 to 1.5 log10 cfu per g matrix at 23°C) advantage to ceftiofur resistant bacteria in the soil and this advantage maintained well-beyond the period of CFM bioavailability; exposure to CFM extends survivorship of cefR E. coli an estimated 80 days compared to non-exposed populations. We also showed that exposing dairy calves to bedding with blaCMY-2 positive E. coli is sufficient for transmission (Chapter III). Consequently, the numerical advantage conferred by exposure to CFM in soil is likely to increase the likelihood transmitting cefR E. coli back to livestock.Department of Veterinary Microbiology and Pathology, Washington State Universit
Polymeric design of cell culture materials that guide the differentiation of human pluripotent stem cells
No full textHuman pluripotent stem cells (hPSCs), including embryonic stem cells (hESCs) and induced pluripotent stem cells (hiPSCs), have the potential to differentiate into many cell types that originate from the three germ layers, such as dopamine-secreting cells and insulin-secreting cells for the treatment of Alzheimer's disease and diabetes, respectively. However, it is challenging to guide hPSC differentiation into desired cell lineages due to their varying differentiation ability. A reasonable strategy is to mimic the stem cell microenvironment for the differentiation of hPSCs into specific cell lineages using optimal polymeric biomaterials for hPSC culture. This review summarizes various methods for differentiating hPSCs cultured on polymeric biomaterials and discusses the optimal methods and cell culture polymeric biomaterials for hPSC differentiation into specific cell lineages. The recent trend in protocols avoids embryoid body (EB, aggregated cells) formation because EBs contain different types of cells. The combination of appropriate differentiation protocols and cell culture polymeric biomaterials for the differentiation of hPSCs into specific cell lineages will produce a large quantity of highly pure GMP-grade differentiated cells for use in translational medicine
Lifestyle and Language in Thirumurugatrupadai
No full textTamil literature clearly reflects the lifestyle of the ancient Tamils. In the field of anthropology Tamil literature plays an important role. The richness of a country's language is judged by the richness of its literature in the regional language spoken by the people of that country. The ideas found in those literary works shapes the mind and lifestyle of both the present and future generation too. Thirumurugatrupadai which is one among the Pattuppattu (anthology) is about a person who is blessed by the lord Murugan, comforting another servant to Murugan. In this text author Nakkiranar has sung songs in six sections about the places where Murugan used to stay such as Tiruparanguntram, Tiruchendur, Palani, Swamimalai, Palamuthircholai and Kuntuthoradal. Thus, the article briefly explains about the Kurinji land people, their customs, how they worshipped lord Murugan, their clothing, accessories, the sense of solidarity with relatives, the spirit of living together, chastity, and the development of virtue. All these things strengthen the richness of the Tamil language
CRISPR-Cas12a has widespread off-target and dsDNA-nicking effects
No full textCas12a (Cpf1) is an RNA-guided endonuclease in the bacterial type V-A CRISPR-Cas anti-phage immune system that can be repurposed for genome editing. Cas12a can bind and cut dsDNA targets with high specificity in vivo, making it an ideal candidate for expanding the arsenal of enzymes used in precise genome editing. However, this reported high specificity contradicts Cas12a’s natural role as an immune effector against rapidly evolving phages. Here, we employed high-throughput in vitro cleavage assays to determine and compare the native cleavage specificities and activities of three different natural Cas12a orthologs (FnCas12a, LbCas12a, and AsCas12a). Surprisingly, we observed pervasive sequence-specific nicking of randomized target libraries, with strong nicking of DNA sequences containing up to four mismatches in the Cas12a-targeted DNA–RNA hybrid sequences. We also found that these nicking and cleavage activities depend on mismatch type and position and vary with Cas12a ortholog and CRISPR RNA (crRNA) sequence. Our analysis further revealed robust non-specific nicking of dsDNA when Cas12a is activated by binding to a target DNA. Together, our findings reveal that Cas12a has multiple nicking activities against dsDNA substrates and that these activities vary among different Cas12a orthologs.This research was originally published in the Journal of Biological Chemistry. Murugan, Karthik, Arun S. Seetharam, Andrew J. Severin, and Dipali G. Sashital. "CRISPR-Cas12a has widespread off-target and dsDNA-nicking effects." Journal of Biological Chemistry (2020): jbc-RA120. © the Author(s). doi: 10.1074/jbc.RA120.012933.</p
Pervasive off-target and double-stranded DNA nicking by CRISPR-Cas12a
No full textCas12a (formerly Cpf1) is an RNA-guided endonuclease in the CRISPR-Cas immune system that can be easily programmed for genome editing. Cas12a can bind and cut dsDNA targets with high specificity in vivo, making it an ideal candidate for precise genome editing applications. This specificity is contradictory to the natural role of Cas12a as an immune effector against rapidly evolving phages. However, the native cleavage specificity and activity remains to be fully understood. We employed high-throughput in vitro cleavage assays to determine and compare the native specificities of three Cas12a orthologs. Surprisingly, we observed pervasive nicking of randomized target libraries, with strong nicking activity observed against targets with up to four mismatches. Nicking and cleavage activities are dependent on mismatch type and position, and vary depending on the Cas12a ortholog and crRNA sequence. Our high-throughput and biochemical analysis further reveal that Cas12a has robust activated non-specific nicking and weak non-specific dsDNA degradation activity in trans. Together, our findings reveal Cas12a cleavage activities that could be beneficial in the context of bacterial CRISPR-Cas immunity but may be detrimental for genome editing technology.This is a pre-print of the article Murugan, Karthik, Arun S. Seetharam, Andrew J. Severin, and Dipali G. Sashital. "Pervasive off-target and double-stranded DNA nicking by CRISPR-Cas12a." bioRxiv (2019): 657791.
DOI: 10.1101/657791.
Attribution 4.0 International (CC BY 4.0).
The copyright holder for this preprint is the author/funder, who has granted bioRxiv a license to display the preprint in perpetuity.
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Rainfall changes over tropical montane cloud forests of southern Western Ghats, India
No full textCitation: Murugan, M., Shetty, P., Anandhi, A., Vasudevan, M., & Gopalan, S. (2009). Rainfall changes over tropical montane cloud forests of southern Western Ghats. Current Science, 97(12), 1755-1760.The southern Western Ghats tropical montane cloud forest sites (Gavi, Periyar, High wavys and Venniyar), which are characterized by frequent or seasonal cloud cover at the vegetation level, are considered one of the most threatened ecosystems in India and the world. Three out of four montane cloud forest sites studied in the southern Western Ghat had experienced diminishing trends of seasonal average and total rainfall, especially during summer monsoon season. The highest level of reduction for summer monsoon season was observed at Gavi rainforest station (>20 mm/14 years) in Kerala followed by Venniyar (>20 mm/20 years) site in Tamil Nadu. Average annual and total precipitation increased during the study period irrespective of the seasons over Periyar area, and the greatest values were recorded for season 2 (>25 mm/28 years). Positive trends for winter monsoon rainfall has been observed for three stations (Periyar, High wavys and Venniyar) except Gavi, and the trend was positive and significant (90%) for Periyar and High wavys. Increase in summer monsoon rainfall was observed for Periyar site and the trend was found to be significant (95%)
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