346 research outputs found
Isolation and characterization of anticoagulant compound from marine mollusc Donax faba (Gmelin, 1791) from Thazhanguda, Southeast Coast of India
Glycosaminoglycans (GAGs) are linear polysaccharides found in the extracellular matrix and biological fluids of animals where they interact with hundreds of proteins and perform a variety of critical roles. There are five classes of animal GAGs: heparan sulfate (HS), chondroitin sulfate (CS), dermatan sulfate (DS), keratan sulfate (KS) and hyaluronan (HA). Many biological functions can be monitored directly by their impact on GAG quantity. In the present study, glycosaminoglycans were isolated from marine bivalve Donax faba. The amount of crude GAG was estimated as 12 gm/kg and of tissue in D. faba. After purification using gel chromatography, the yield was found to be 0.83 mg/kg. The bivalve showed the anticoagulant activity of the crude and purified samples 58 and 114 USP units/mg correspondingly in D. faba. The structural characterization of anticoagulant GAG was analyzed by Fourier transform infrared spectroscopy. Among the marine bivalve, D. faba purified showed more anticoagulant activity than that of crude sample. The results of this study suggest that the GAG from D. faba could be an alternative source of heparin.Keywords: Donax faba, GAGs crude and purified, anticoagulant activity, Fourier transform- infra red (FTIR).African Journal of Biotechnology Vol. 12(40), pp. 5968-597
Electronic-Structure Calculations of Cation-Ordered II-III Layered Double Hydroxides: Origin of the Distortion of the Metal-Coordination Symmetry
Cation ordering brings down the crystal symmetry and introduces distortion into the coordination polyhedra around the divalent cations. In particular, edge sharing of the differently sized M(OH)6 polyhedra causes a non-uniform distension of the array of hydroxy ions. The question arises as to whether this distortion has its origin in the Jahn�Teller distortion of metal coordination or a 2D �Peierls�-type distortion of the array of hydroxy ions. To address this question, DFT calculations were performed on the sulfate-intercalated Cu�Cr, Zn�Cr, and Zn�Al layered double hydroxides (LDHs). An analysis of the density of states shows that the distortion of the Cu2+ coordination polyhedron is due to the Jahn�Teller effect, whereas the Zn2+ coordination polyhedron in Zn�Al LDH likely suffers a �Peierls�-type distortion. In the Zn�Cr LDH, electronic-structure calculations do not predict any distortion in the metal coordination, which is in agreement with experimental results that show only a slight departure from ideal symmetry. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinhei
DIELECTRIC RELAXATION STUDIES OF AMIDES WITH 2-METHOXYETHANOL AND 2- BUTOXYETHANOL USING TIME DOMAIN REFLECTOMETRY TECHNIQUE
ABSTRACT Complex dielectric permittivity measurements of amides like Formamide (FA), N-methylformamide (NMF) and N,N-dimethylformamide (DMF) with alcohols such as 2-methoxyethanol (2-ME) and 2-butoxyethanol (2-BE) has been carried out at different concentration in the frequency range of 10MHz to 30GHz using Time Domain Reflectometry (TDR). The least squares fit method has been used to obtain the static dielectric constant (ε 0 ), relaxation time (τ) and Bruggeman factor (f B ) for binary mixtures. The Bruggeman plot shows a deviation from linearity. This deviation was attributed to some sort of molecular interaction which may take place between the unlike molecules. The effective Kirkwood correlation factor (g eff ) and corrective Kirkwood correlation factor (g f ) of the mixtures have been determined and discussed to yield information on the structure and dynamics of the mixtures and it confirms the structural formation due to intermolecular interaction between amides with 2-ME and 2-BE. The relaxation time is increasing with increasing chain length of alcohols and is decreasing with increasing amide concentration. The excess static dielectric constant (ε E ) and excess inverse relaxation time (1/τ) E values are indicates that is a form of hydrogen bonding interaction between the 2-ME and 2-BE with amides systems, for all the mixtures dipoles are slowly rotated. The free energy of activation for relaxation time (ΔF τ ) is greater for initial concentration in all the system studied
SUMMARY
Cushing’s syndrome is a pathological condition associated with excessive cortisol production, the commonest etiology being Cushing’s disease. Corticosteroids in high doses have been used in the management of Steven Johnson Syndrome (SJS) with favourable outcome. We describe a patient with Cushing’s disease who developed SJS, one week after taking sperulina a product from sea-weed while waiting for transphenoidal surgery. KEY WORDS
Socio Economic Development of Coastal People Through Kappaphycus alverzii Farming Using Different Cultivation Methods in Tamil Nadu, Southeast Coast of India
Kappaphycus (a kappa carrageenan yielding red seaweed) cultivation was initiated in 1960 and by 1969 a farm was established by Marine colloids and MS Doty in Tawii Tawii province of Philippine waters. Following the success of its cultivation in Philippines, the same had been expanded worldwide. Kappaphycus alvarezii along with Kappaphycus striatum has been introduced in more than 20 tropical countries. Kappaphycus alone had been introduced in 26 countries. Its commercial cultivation is successfully going on in China, Indonesia, Madagascar, Malaysia, Philippines and Tanzania. In India, a scientist from Central Salt and Marine Chemical Research Institute (CSMCRI-CSIR), Bhavnagar, Gujarat was brought this alga from Japan though its original origin is from Philippines during 1984 for research and cultivation after following the necessary quarantine and introduction procedures. K. alvarezii was introduced in September 1995 at Thonithurai (Mandapam near Pamban Bridge), in the Gulf of Mannar waters, Tamilnadu, India. After repeated domestication and experimentation at Mandapam cultivation technology was transferred to PepsiCo India Holdings Pvt. Ltd., Gurgaon in 2001 and expanded the same on the Palk Bay side of the Bay of Bengal. This cultivation was taken up by self-help groups (SHGs) for their livelihood. The present study deals with comparison of different cultivation methods of this alga and its economics in Ramanathapuram district, Tamil Nadu, southeast coast of India. The income with the respective mean annual crop yield was calculated (US 277), Rs.16063/- (US 276) and 20900/- (US 292) , Rs.18063/- (US 291) and Rs. 22400/- (US$ 339) per month/ person once the loan period (of three years) is over. In view of the commercial cultivation, we recommend net enclosed open culture in the shallow water, raft culture in the moderate wave motion areas and tubular culture & net bag culture in the open sea after analyzing the infra cost, replacement of the infra, cultivation operation, carrageenan yield and net income. The income might increase if the farmers maintain the farm well coupled with per kg cost increase by the buyer.Keywords: Kappaphycus alvarezii, Crop yield, Income, Coastal people, Seaweed, Cultivatio
Viewpoint-based testing of concurrent components
The use of multiple partial viewpoints is recommended for specification. We believe they also can be useful for devising strategies for testing. In this paper, we use Object-Z to formally specify concurrent Java components from viewpoints based on the separation of application and synchronisation concerns inherent in Java monitors. We then use the Test-Template Framework on the Object-Z viewpoints to devise a strategy for testing the components. When combining the test templates for the different viewpoints we focus on the observable behaviour of the application to systematically derive a practical testing strategy. The Producer-Consumer and Readers-Writers problems are considered as case studies
Genomic modelling of the ESR1 Y537S mutation for evaluating function and new therapeutic approaches for metastatic breast cancer
Drugs that inhibit estrogen receptor-α (ER) activity have been highly successful in treating and reducing breast cancer progression in ER-positive disease. However, resistance to these therapies presents a major clinical problem. Recent genetic studies have shown that mutations in the ER gene are found in >20% of tumours that progress on endocrine therapies. Remarkably, the great majority of these mutations localize to just a few amino acids within or near the critical helix 12 region of the ER hormone binding domain, where they are likely to be single allele mutations. Understanding how these mutations impact on ER function is a prerequisite for identifying methods to treat breast cancer patients featuring such mutations. Towards this end, we used CRISPR-Cas9 genome editing to make a single allele knock-in of the most commonly mutated amino acid residue, tyrosine 537, in the estrogen-responsive MCF7 breast cancer cell line. Genomic analyses using RNA-seq and ER ChIP-seq demonstrated that the Y537S mutation promotes constitutive ER activity globally, resulting in estrogen-independent growth. MCF7-Y537S cells were resistant to the anti-estrogen tamoxifen and fulvestrant. Further, we show that the basal transcription factor TFIIH is constitutively recruited by ER-Y537S, resulting in ligand-independent phosphorylation of Serine 118 (Ser118) by the TFIIH kinase, cyclin-dependent kinase (CDK)7. The CDK7 inhibitor, THZ1 prevented Ser118 phosphorylation and inhibited growth of MCF7-Y537S cells. These studies confirm the functional importance of ER mutations in endocrine resistance, demonstrate the utility of knock-in mutational models for investigating alternative therapeutic approaches and highlight CDK7 inhibition as a potential therapy for endocrine-resistant breast cancer mediated by ER mutations
Structure models for the hydrated and dehydrated nitrate-intercalated layered double hydroxide of Li and Al
Aristolochic Acid I Induced Autophagy Extenuates Cell Apoptosis via ERK 1/2 Pathway in Renal Tubular Epithelial Cells
Autophagy is a lysosomal degradation pathway that is essential for cell survival and tissue homeostasis. However, limited information is available about autophagy in aristolochic acid (AA) nephropathy. In this study, we investigated the role of autophagy and related signaling pathway during progression of AAI-induced injury to renal tubular epithelial cells (NRK52E cells). The results showed that autophagy in NRK52E cells was detected as early as 3–6 hrs after low dose of AAI (10 µM) exposure as indicated by an up-regulated expression of LC3-II and Beclin 1 proteins. The appearance of AAI-induced punctated staining of autophagosome-associated LC3-II upon GFP-LC3 transfection in NRK52E cells provided further evidence for autophagy. However, cell apoptosis was not detected until 12 hrs after AAI treatment. Blockade of autophagy with Wortmannin or 3-Methyladenine (two inhibitors of phosphoinositede 3-kinases) or small-interfering RNA knockdown of Beclin 1 or Atg7 sensitized the tubular cells to apoptosis. Treatment of NRK52E cells with AAI caused a time-dependent increase in extracellular signal-regulated kinase 1 and 2 (ERK1/2) activity, but not c-Jun N-terminal kinase (JNK) and p38. Pharmacological inhibition of ERK1/2 phosphorylation with U0126 resulted in a decreased AAI-induced autophagy that was accompanied by an increased apoptosis. Taken together, our study demonstrated for the first time that autophagy occurred earlier than apoptosis during AAI-induced tubular epithelial cell injury. Autophagy induced by AAI via ERK1/2 pathway might attenuate apoptosis, which may provide a protective mechanism for cell survival under AAI-induced pathological condition
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