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The concentration of ascorbic acid (AA) and the histochemical distribution of this vitamin together with cytochrome oxidase have been investigated in the normal and regenerating tail of the Scincid lizard, Mabuya carinata. An interesting aspect of this investigation is the observation of a total lack of cytochrome oxidase in both the normal and regenerating tail of the lizard, except for the differentiating phase. On the other hand, AA has been found to be present in the normal and regenerating tail with above normal levels during wound healing (twofold) and differentiation (fivefold). In the light of the poor cytochrome oxidase activity, the higher content of AA noted during regeneration has been construed to play a possible role in the respiratory mechanics of the regenerating lizard tail. Further, the importance of AA in cellular metabolism and the wound healing and differentiative processes have also been discussed. 相似文献
13.
Karthik Sivaraman Aditi Chopra Aparna Narayana Raghu A. Radhakrishnan 《Gerodontology》2021,38(1):17-26
Severe acute respiratory syndrome coronavirus 2 (SARS‐CoV‐2) is an RNA virus that causes coronavirus infection (COVID‐19). COVID‐19 is a highly contagious disease transmitted through respiratory droplets, saliva and other contact routes. Within 10 months of its outbreak, SARS‐CoV‐2 has infected more than 23 million people around the world. Evidence suggests that older adults are the most vulnerable to infection and have an increased risk of mortality. Reduced immunity and underlying medical conditions make them risk‐prone and vulnerable to critical care. Older adults affected with the SARS‐CoV‐2 virus present with distinct clinical manifestations necessitating specific treatment needs and management protocols. While it is crucial to prevent the spread of novel coronavirus (2019‐nCoV), the role of oral healthcare workers in addressing the specific needs of ageing adult patients by adopting specific guidelines and appropriate infection control protocols is timely. This paper aims to develop specific guidelines and protocols for the dental management of geriatric patients during the COVID‐19 pandemic. 相似文献
14.
Kuttanelloor Roshni Chelapurath Radhakrishnan Renjithkumar 《Zeitschrift fur angewandte Ichthyologie》2021,37(1):135-136
The length–weight relationships (LWRs) of four fish species were determined from Vembanad-Kole Wetland, Kerala, India between June 2015 and May 2016. Fish samples were collected monthly from various fishing gears such as gill nets (50 m long and 1.5 m height, mesh sizes 30–100 mm, soaking time 8 hr) and seine nets (mesh sizes 8–16 mm). Values of the parameter b ranged from 2.896 to 3.165 and such values are within the expected range. This study reports the new maximum total length for Channa pseudomarulius and Hyporhamphus xanthopterus. 相似文献
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Alexei Kharitonenkov John M. Beals Radmila Micanovic Beth A. Strifler Radhakrishnan Rathnachalam Victor J. Wroblewski Shun Li Anja Koester Amy M. Ford Tamer Coskun James D. Dunbar Christine C. Cheng Christopher C. Frye Thomas F. Bumol David E. Moller 《PloS one》2013,8(3)
Fibroblast growth factor 21 is a novel hormonal regulator with the potential to treat a broad variety of metabolic abnormalities, such as type 2 diabetes, obesity, hepatic steatosis, and cardiovascular disease. Human recombinant wild type FGF21 (FGF21) has been shown to ameliorate metabolic disorders in rodents and non-human primates. However, development of FGF21 as a drug is challenging and requires re-engineering of its amino acid sequence to improve protein expression and formulation stability. Here we report the design and characterization of a novel FGF21 variant, LY2405319. To enable the development of a potential drug product with a once-daily dosing profile, in a preserved, multi-use formulation, an additional disulfide bond was introduced in FGF21 through Leu118Cys and Ala134Cys mutations. FGF21 was further optimized by deleting the four N-terminal amino acids, His-Pro-Ile-Pro (HPIP), which was subject to proteolytic cleavage. In addition, to eliminate an O-linked glycosylation site in yeast a Ser167Ala mutation was introduced, thus allowing large-scale, homogenous protein production in Pichia pastoris. Altogether re-engineering of FGF21 led to significant improvements in its biopharmaceutical properties. The impact of these changes was assessed in a panel of in vitro and in vivo assays, which confirmed that biological properties of LY2405319 were essentially identical to FGF21. Specifically, subcutaneous administration of LY2405319 in ob/ob and diet-induced obese (DIO) mice over 7–14 days resulted in a 25–50% lowering of plasma glucose coupled with a 10–30% reduction in body weight. Thus, LY2405319 exhibited all the biopharmaceutical and biological properties required for initiation of a clinical program designed to test the hypothesis that administration of exogenous FGF21 would result in effects on disease-related metabolic parameters in humans. 相似文献
17.
Shabeesh Balan Sarada lekshmi Koramannil Radha Sanish Sathyan Joseph Vijai Moinak Banerjee Kurupath Radhakrishnan 《Gene》2013
The human major vault protein (MVP) has been implicated in the development of drug resistance in cancer cells. Over expression of MVP has also been reported in brain tissue samples from antiepileptic drug (AED)-resistant human focal epilepsies. To investigate the relationship between single nucleotide polymorphisms (SNPs) involving the MVP gene and AED-resistance, we compared the distribution of three SNPs in the MVP gene, rs4788187, rs3815824 and rs3815823, among 220 patients with mesial temporal lobe epilepsy with hippocampal sclerosis (MTLE-HS) (prototype of AED-resistant epilepsy syndrome), 201 patients with juvenile myoclonic epilepsy (JME) (prototype of AED-responsive epilepsy syndrome) and 213 ethnically matched non-epilepsy controls. All the patients and controls were residents of the South Indian state of Kerala for more than three generations. We did not find any significant difference in allele and genotypic frequencies of the studied SNPs between AED-resistant and AED-responsive cohorts, and between AED-resistant and AED-responsive cohorts independently and pooled together when compared with the controls. We conclude that rs4788187, rs3815824, rs3815823 variants of the MVP gene are associated neither with predisposition for epilepsy nor with AED-resistance in the population that we have studied. Our results suggest the need for further research into the link between MVP and AED-resistance. 相似文献
18.
Hongyan Zheng Alina Beliavsky Anatoli Tchigvintsev Joseph S. Brunzelle Greg Brown Robert Flick Elena Evdokimova Zdzislaw Wawrzak Radhakrishnan Mahadevan Wayne F. Anderson Alexei Savchenko Alexander F. Yakunin 《Proteins》2013,81(6):1031-1041
Aldehyde dehydrogenases are found in all organisms and play an important role in the metabolic conversion and detoxification of endogenous and exogenous aldehydes. Genomes of many organisms including Escherichia coli and Salmonella typhimurium encode two succinate semialdehyde dehydrogenases with low sequence similarity and different cofactor preference (YneI and GabD). Here, we present the crystal structure and biochemical characterization of the NAD(P)+‐dependent succinate semialdehyde dehydrogenase YneI from S. typhimurium. This enzyme shows high activity and affinity toward succinate semialdehyde and exhibits substrate inhibition at concentrations of SSA higher than 0.1 mM. YneI can use both NAD+ and NADP+ as cofactors, although affinity to NAD+ is 10 times higher. High resolution crystal structures of YneI were solved in a free state (1.85 Å) and in complex with NAD+ (1.90 Å) revealing a two domain protein with the active site located in the interdomain interface. The NAD+ molecule is bound in the long channel with its nicotinamide ring positioned close to the side chain of the catalytic Cys268. Site‐directed mutagenesis demonstrated that this residue, as well as the conserved Trp136, Glu365, and Asp426 are important for activity of YneI, and that the conserved Lys160 contributes to the enzyme preference to NAD+. Our work has provided further insight into the molecular mechanisms of substrate selectivity and activity of succinate semialdehyde dehydrogenases. © 2012 Wiley Periodicals, Inc. 相似文献
19.
G. Archana K. Sabina S. Babuskin K. Radhakrishnan Mohammed A. Fayidh P. Azhagu Saravana Babu M. Sivarajan M. Sukumar 《Carbohydrate polymers》2013
In the present investigation, the polysaccharide/mucilage from waste of Abelmoscus esculentus by modification in hot extraction using two different solvents (Acetone, Methanol) were extracted, characterized and further compared with seaweed polysaccharide for their potential applications. The percentage yield, emulsifying capacity and swelling index of this mucilage were determined. The macro algae and okra waste, gave high % yield (22.2% and 8.6% respectively) and good emulsifying capacity (EC% = 52.38% and 54.76% respectively) with acetone, compared to methanol (11.3% and 0.28%; EC% = 50%) (PH = 7) while swelling index was greater with methanol than acetone extracts respectively. The infrared (I.R.) spectrum of the samples was recorded to investigate the chemical structure of mucilage. Thermal analysis of the mucilage was done with TGA (Thermal Gravimetric Analyzer) and DSC (Differential Scanning Calorimeter) which showed both okra and algal polysaccharide were thermostable hydrogels. 相似文献
20.
Xiaoxiao Cheng Vaclav Veverka Anand Radhakrishnan Lorna C. Waters Frederick W. Muskett Sara H. Morgan Jiandong Huo Chao Yu Edward J. Evans Alasdair J. Leslie Meryn Griffiths Colin Stubberfield Robert Griffin Alistair J. Henry Andreas Jansson John E. Ladbury Shinji Ikemizu Mark D. Carr Simon J. Davis 《The Journal of biological chemistry》2013,288(17):11771-11785