RNAi: An innate gene knockdown mechanism

RNA interference (RNAi) is an evolutionary conserved mechanism in alleukaryotic cells whose role is to down-regulate the gene expression in the nucleus known as Transcriptional Gene silencing (TGS) and in the cytoplasm known as Post Transcriptional Gene Silencing (PTGS). It can occur at different stages of cell cycles during cell proliferation,  developmental stage and cell death. An artificially induced Double Stranded RNA (dsRNA) in a eukaryotic organism like C. elegans can also cause RNAi by sequence specific gene silencing. The Double Stranded RNA (dsRNA) derived small RNAs (19-28nt in length) along with Argonaute protein, Dicer (RNase III like enzyme) and other cofactors act as molecular scissors which degrade the homologous mRNA. This effector-protein complex is termed as RNA-induced silencing complex (RISC) which searches for the homologous transcripts of mRNA to degrade them. The Small RNA which might be either a Small Interference RNA (siRNA) or a microRNA (miRNA) along with the effector complex directs the endonuclease cleavage to occur on the target mRNA thereby preventing the expression of transcripts. This overall process is termed as RNAi (RNA interference)

Rare occurrence of diamond back squid Thysanoteuthis rhombus (Troschel, 1867) off Chennai coast

A single female specimen of diamond back squid Thysanoteuthis rhombus (Troschel, 1857) locally called 'thalan kadama' was recorded for the first time in the landings of Kasimedu Fishing Harbour on 9.7.2008. The squid was caught in the drift gill net operated off north Chennai at a depth of around 100 m

SYNTHESIS, BIOLOGICAL EVALUATION, AND DOCKING STUDY OF NOVEL 2-PHENYL-1- BENZOPYRAN-4-ONE DERIVATIVES - AS A POTENT CYCLOOXYGENASE-2 INHIBITOR

Objective: The inflammation and oxidative stress were related together in the generation of reactive oxygen species, which is responsible for the enhancement of inflammation associated with various chronic diseases. Methods: The aim of this study is to synthezise and characterizes the flavones (2-phenyl-1-benzopyran-4-one) derivatives and analyzed by their docking hypothetical data as an effective anti-inflammatory mediator against cyclooxygenase-2 (COX-2) enzyme. Further, the evaluation of various in vitro antioxidant and anti-inflammatory studies was carried out. Results: The 10 compounds were synthesized and characterized by ultraviolet, infrared, nuclear magnetic resonance, and mass spectroscopic techniques. The docking data results of these 10 flavones derivatives against COX-2 enzymes (Protein Data Bank ID: 3LN1) showed the binding energy ranging between −5.53 kcal/mol and −7.02 kcal/mol when compared with that of the standard diclofenac (−6.34 kcal/mol). The in vitro studies suggest that the lipophilic character of the side chain donor, along with the hydroxyl substituted flavones found to have significant half maximal inhibitory concentration values. Conclusion: Based on these in silico and in vitro evaluation results, these synthesized compounds could act as a promising inhibitor to target the COX- 2 enzyme. Hence, those compounds were effective in the management of chronic diseases by exhibits free radical scavenging and anti-inflammatory property

Structural basis of SNAPc-dependent snRNA transcription initiation by RNA polymerase II

RNA polymerase II (Pol II) carries out transcription of both protein-coding and non-coding genes. Whereas Pol II initiation at protein-coding genes has been studied in detail, Pol II initiation at non-coding genes, such as small nuclear RNA (snRNA) genes, is less well understood at the structural level. Here, we study Pol II initiation at snRNA gene promoters and show that the snRNA-activating protein complex (SNAPc) enables DNA opening and transcription initiation independent of TFIIE and TFIIH in vitro. We then resolve cryo-EM structures of the SNAPc-containing Pol IIpre-initiation complex (PIC) assembled on U1 and U5 snRNA promoters. The core of SNAPc binds two turns of DNA and recognizes the snRNA promoter-specific proximal sequence element (PSE), located upstream of the TATA box-binding protein TBP. Two extensions of SNAPc, called wing-1 and wing-2, bind TFIIA and TFIIB, respectively, explaining how SNAPc directs Pol II to snRNA promoters. Comparison of structures of closed and open promoter complexes elucidates TFIIH-independent DNA opening. These results provide the structural basis of Pol II initiation at non-coding RNA gene promoters

Autologous Immune Enhancement Therapy in Recurrent Ovarian Cancer with Metastases: A Case Report

Current therapeutic modalities for ovarian cancer such as chemotherapy, radiotherapy and surgery have been reported to yield only marginal success in improving survival rates of patients and have associated adverse effects. We report here a case of recurrent stage IV ovarian cancer, treated with cell-based autologous immune enhancement therapy (AIET) along with chemotherapy and followed up for 18 months. A 54-year-old female was diagnosed with a recurrence of ovarian carcinoma 1 year after initial surgical removal followed by chemotherapy for stage IIIC ovarian carcinoma. When diagnosed in 2010 with recurrence, she had liver and spleen metastases with a CA-125 level of 243 U/ml and a stage IV clinical status. Six infusions of AIET using autologous in vitro expanded and activated natural killer (NK) cells (CD3–CD56+) and activated T lymphocytes (CD3+CD56+) were administered in combination with 6 cycles of chemotherapy with carboplatin and doxorubicin. Following this treatment, CA-125 decreased to 4.7 U/ml along with regression of the metastatic lesions and an improved quality of life. No adverse reactions were reported after the AIET transfusions. Eighteen months of follow-up revealed a static nonprogressive disease. Combining AIET with chemotherapy and other conventional treatments has been found to be effective in our experience, as reported earlier, even in patients with advanced ovarian cancer, and we recommend this strategy be considered in treating similar cases

Electrodeposition of Zinc from Low Temperature Molten Salt Electrolyte: Part II - Imidazole – Alcl3/Zinc Chloride LTMS

Low Temperature Molten salts (LTMS) have a number of applications in metal finishing including electrolytic deposition and anodic processes like polishing and colouring. Imidazolium, pyridinium and choline based cations are normally used in LTMS [1-5]. Zinc deposition was carried out from imidazole - AlCl3 / ZnCl2 LTMS electrolyte at temperature < 100º C and the mole ratio was optimized in our research. Surface morphology of electrodeposited coatings was characterized by SEM and XRD. Cathodic and anodic current efficiencies of Imidazole – AlCl3 / ZnCl2 LTMS were evaluated

Electrodeposition of Zinc From Low Temperature Molten Salt Electrolyte:Part I-Imidazole And Zinc-Chloride Electrolyte

Abstract: Our R & D work was focused on the electro deposition of Zinc from imidazole as low temperature molten salt (LTMS) electrolyte with zinc chloride as a supporting salt at <100º C., without required controls from the previous existing non aqueous baths as well additive free system for the zinc deposition. Surface morphological studies and crystallographic orientation results were evaluated

Electroless deposition of composite coatings containing kaolin nanoparticles

The ability to codeposit particulate matter in a matrix of electroless nickel has led to a new generation of composite coatings with unique properties, such as high hardness wear, abrasion, corrosion and high temperature oxidation resistance. In this paper, the authors report on the development of electroless Ni–P–kaolin composite coating, and the characteristic properties of the selected deposits were evaluated by scanning electron microscopy, energy dispersive X-ray and X-ray diffraction techniques. A good rate of deposition of 12 mm h21 was observed for the optimised concentration of 6 g L21 of kaolin in the bath. For the optimised bath composition and operating conditions, the composite deposit was found to contain 81?7%Ni, 9?8%P and 10?5%kaolin. Heat treatment at 400uC for 1 h results in an increase in the hardness and wear resistance of the composite coating. The corrosion resistance is also highly enhanced by the incorporation of kaolin in the nickel–phosphorus matrix. The crystallite size of the composite coating is 20 nm, and the codeposition of kaolin follows the Langmuir adsorption isotherm

Zn- Ni Alloy Deposit for Cadmium Replacement Applications

sigamani.cecri.res.in Zinc- nickel alloy was deposited from alkaline bath at a PH of 13-14 with the nickel percentage of 5-9% in our prior research. Present study dealt with the research on 10-12 % of Nickel at a PH of 12-13 from Zinc – nickel alloy electrolyte and the remaining percentage of Zinc, required for corrosion resistant applications to be used for reliable alternative of cadmium. Hull cell studies was carried out to optimize current density, temperature, agitation etc., for getting a deposition of 10-12 % of Ni &amp; 88-90 % of Zn. SEM, EDAX, XRD measurements characterize the deposit properties and structure. Corrosion resistance measurements such as polarisation, corrosion impedance spectra of zinc-nickel alloy were evaluated

Clinical and hematological evaluation of geriatric anemia

Background: Anemia in the elderly is a cause of concern. It is not merely physiological due to aging and requires appropriate evaluation. Anemia has a significant negative impact on cardiac function, cognition, sleep, frequent hospitalization, mobility, morbidity, and mortality. Anemia in the elderly is attributable to many causes: nutrient deficiencies, chronic inflammatory diseases, thyroid disorders, diabetes mellitus, gastrointestinal (GI) tumors and bleeding, chemotherapy-induced anemia, and drug-induced hemolysis. Objectives: We aimed to evaluate the clinical and hematological profile of anemia in 100 patients aged above 60 years. Methods and Material: We performed a cross-sectional type of study in a tertiary care center including male and female patients aged 60 years and above and whose hemoglobin was less than 13 g/dl and less than 12 g/dl, respectively. Clinical history, complete blood picture, and peripheral smear were obtained in all patients. Serum iron profile was done in patients with micro-normocytic anemia. Vitamin B12 and folate assays were done in patients with normo-macrocytic anemia and those with pancytopenia. Bone marrow studies and endoscopies were done in cases wherever deemed appropriate. Results: The majority of the patients had either severe or moderate anemia. 49% of the patients had normocytic anemia. The commonest cause for anemia was nutritional deficiencies (45%) followed by anemia of chronic inflammation (40%) and unexplained anemia (8%). Conclusions: It is essential that anemia deserves its due attention in clinical practice in older patients and is not normal always