sandeep singh - Academia.edu (original) (raw)

Papers by sandeep singh

ChemInform, 1997

ABSTRACT ChemInform is a weekly Abstracting Service, delivering concise information at a glance t... more ABSTRACT ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

LWT - Food Science and Technology, 2015

ABSTRACT The aim of the present work is to develop biodegradable polymeric nanoparticles based or... more ABSTRACT The aim of the present work is to develop biodegradable polymeric nanoparticles based oral drug delivery for encapsulation and controlled release of polyphenolic flavonoid (quercetin). The quercetin loaded poly (ɛ caprolactone) nanoparticles were prepared by nano-precipitation method using 32 factorial designs. The results of optimized formulations OPF1, OPF2 and OPF3 showed particle size of 215.9 ± 2.9, 228.6 ± 2.7, 253.4 ± 3.3 nm, the entrapment efficiency of 66.32 ± 0.4, 67.82 ± 0.7, 69.33 ± 1.0%, and drug release at 48 h of 66.05 ± 1.41, 64.12 ± 0.30, 62.82 ± 0.85%, respectively. SEM and AFM images represent spherical and smooth surface of nanoparticles. The results suggest that optimized formulations could promote the control release, and improves the physical stability of quercetin. In conclusion, polymeric nanoparticles could be a promising carrier for oral delivery of quercetin.

Indian Journal of Thoracic and Cardiovascular Surgery, 2005

Background: To share our initial experience with cases of Tetralogy of Fallot (TOF) in whom trans... more Background: To share our initial experience with cases of Tetralogy of Fallot (TOF) in whom transpulmonary artery route was exclusively used for repair of the defect.

Special Paper of the Geological Society of America, 1999

Geological Society of America Special Paper 328 1999 Metamorphic evolution of the northwest Himal... more Geological Society of America Special Paper 328 1999 Metamorphic evolution of the northwest Himalaya, India: Pressure. temperature data, inverted metamorphism, and exhumation in the Kashmir, Himachal, and Garhwal Himalayas RM Manickavasagam, Arvind K. Jain, ...

Sedimentary Geology, 2007

Soft-sediment deformational structures are important diagnostic features of paleoseismic studies.... more Soft-sediment deformational structures are important diagnostic features of paleoseismic studies. These seismites result from local vigorous fluidization and hydroplastic deformation formed during liquefaction as a direct consequence of permanent deformation of ground surface due to earthquakes of large magnitude.

Tectonophysics, 2008

New geological observations, recent published data and U-Pb SHRIMP zircon dating from the Karakor... more New geological observations, recent published data and U-Pb SHRIMP zircon dating from the Karakoram Mountains along the Nubra and Shyok Rivers reveal that the initial subduction of the Tethyan oceanic lithosphere took place~110 Ma beneath the Paleozoic-Mesozoic platform of the southern edge of the Asian Plate. This has produced the I-type plutons within the Karakoram Batholith Complex, well before the juxtaposition of the Asian Plate along the Karakoram Shear Zone. Within this shear zone, U-Pb zircon crystallisation ages of~75 Ma from mylonitised granitoids and 68 Ma from undeformed Tirit granodiorite constrain the timing of suturing of the Karakoram terrain with the Trans-Himalaya between 75 and 68 Ma. Post-shearing leucogranite was episodically generated within frontal migmatised Karakoram Metamorphic Belt and emplaced between 20 and 13 Ma within the shear zone. Presence of a low resistivity zone as a possible indication of mid-crustal partial molten crust underneath the Higher Himalaya-Ladakh-Karakoram terrains manifests the impingement of the Indian Plate along the Main Himalayan Thrust at depth.

International Journal of Earth Sciences, 2009

The influx of Sr responsible for increase in marine Sr has been attributed to rise of Himalaya an... more The influx of Sr responsible for increase in marine Sr has been attributed to rise of Himalaya and weathering of the Himalayan rocks. The rivers draining Himalaya to the ocean by the northern part of the Indian sub-continent comprising the Ganga Alluvial Plain (GAP) along with Central parts of the Himalaya and the northern part of the Indian Craton are held responsible for the transformation of Sr isotopic signature. The GAP is basically formed by the Himalayan-derived sediments and serves as transient zone between the source (Himalaya) and the sink (Bay of Bengal). The Gomati River, an important alluvial tributary of the Ganga River, draining nearly 30,500 km 2 area of GAP is the only river which is originating from the GAP. The river recycles the Himalayanderived sediments and transport its weathering products into the Ganga River and finally to Bay of Bengal. 11 water samples were collected from the Gomati River and its intrabasinal lakes for measurement of Sr isotopic composition. Sr concentration of Gomati River water is about 335 lg/l, which is about five times higher than the world's average of river water (70 lg/l) and nearly three times higher than the Ganga River water in the Himalaya (130 lg/l) The Sr isotopic ratios reported are also higher than global average runoff (0.7119) and to modern seawater (0.7092) values. Strong geochemical sediment-water interaction appearing on surface is responsible for the dissolved Sr isotopic ratios in the River water. Higher Sr isotopic rations found during post-monsoon than in premonsoon season indicate the importance of fluxes due to monsoonal erosion of the GAP into the Gomati River. Monsoon precipitation and its interaction with alluvium appear to be major vehicle for the addition of dissolved Sr load into the alluvial plain rivers. This study establishes that elevated 87 Sr/ 86 Sr ratios of the Gomati River are due to input of chemical weathering of alluvial material present in the Ganga Alluvial Plain.

Journal of Pharmaceutical Investigation, 2014

ABSTRACT The present research demonstrates the development and characterization of alginate based... more ABSTRACT The present research demonstrates the development and characterization of alginate based multiunit floating dosage form for sustained delivery of cefdinir to the upper gastrointestinal tract. The method involved ionic gelation of sodium alginate solution containing suspended drug and myristyl alcohol (release modifier and buoyancy regulator) by calcium ions followed by freeze drying. Fourier transform infrared spectroscopy and differential scanning calorimetry studies revealed that there were no incompatibilities between drug and excipients. The effect of various process variables; amount of sodium alginate, myristyl alcohol and cefdinir; on critical parameters like drug loading, particle size and mean dissolution time (MDT) was modelled using Box–Behnken design and studied using response surface plots and regression equations. The observed and predicted r 2 values were in agreement in case of all the responses which marks the validity of developed model. The particle size, drug loading and MDT were found to be strongly dependent on the variables studied. The beads showed high drug loading up to 65.41 % and extended drug release up to 24 h in 0.1 N hydrochloric acid. The beads exhibited 100 % buoyancy without any lag time up to 24 h despite of the high drug loading. The mechanism of drug release was found to be Fickian diffusion.

The international journal of biochemistry & cell biology, 2010

Tumor suppressor SMAR1 is known to be involved in regulation of cell cycle and apoptotic genes tr... more Tumor suppressor SMAR1 is known to be involved in regulation of cell cycle and apoptotic genes transcription. It also directly interacts and stabilizes p53 through phosphorylation at serine-15 residue. Although the functions of SMAR1 are mainly restricted to the nucleus, we report its novel function with the cytoplasm. We show that SMAR1 directly interacts and inhibits AKR1a4 enzyme activity. Interestingly, AKR1a4 enzyme activity is elevated in higher grades of breast cancer where SMAR1 expression is drastically downregulated. Higher AKR1a4 activity protects the cancer cells from anticancer drugs and free radical stress. Through increased metabolism, ARK1a4 helps fulfilling higher energy needs required by cancer cell. The present study delineates yet another facet of tumor suppressor activity of SMAR1 in the cytoplasm. We also depict that upon stress, ATM kinase leads to dissociation of SMAR1-AKR1a4 complex through nuclear translocation of SMAR1 causing elevated AKR1a4 activity. Nuc...

Virology, Jan 25, 2010

Nuclear Matrix and MARs have been implicated in the transcriptional regulation of host as well as... more Nuclear Matrix and MARs have been implicated in the transcriptional regulation of host as well as viral genes but their precise role in HIV-1 transcription remains unclear. Here, we show that >98% of HIV sequences contain consensus MAR element in their promoter. We show that SMAR1 binds to the LTR MAR and reinforces transcriptional silencing by tethering the LTR MAR to nuclear matrix. SMAR1 associated HDAC1-mSin3 corepressor complex is dislodged from the LTR upon cellular activation by PMA/TNFalpha leading to an increase in the acetylation and a reduction in the trimethylation of histones, associated with the recruitment of RNA Polymerase II on the LTR. Overexpression of SMAR1 lead to reduction in LTR mediated transcription, both in a Tat dependent and independent manner, resulting in a decreased virion production. These results demonstrate the role of SMAR1 in regulating viral transcription by alternative compartmentalization of LTR between the nuclear matrix and chromatin.

Himalayan Journal of Sciences, 2008

Journal of Agricultural Science, 2003

A field experiment was conducted for two years at Bangalore, to study the influence of organic (v... more A field experiment was conducted for two years at Bangalore, to study the influence of organic (vermicompost) and inorganic fertilizers (NPK) on growth, yield and nutrient uptake of patchouli (Pogostemon cablin) in a semi-arid tropical climate. The results revealed that application of vermicompost (5 t ha -1 ) + 50% NPK (100 : 25 : 25 kg ha -1 ) produced significantly higher herbage and oil yield (13.98 t ha -1 and 83.4 kg ha -1 ), respectively, which was on par with recommended dose of NPK (200 : 50 : 50 kg ha -1 ). Application of vermicompost (5 t ha -1 ) + 50% NPK (100 : 25 : 25 kg ha -1 ) increased the nitrogen, phosphorus and potassium uptake, respectively, which was at par with recommended dose of NPK (200 : 50 : 50 kg ha -1 ). Oil content was not influenced by organic and inorganic fertilizers.

Sugar Tech, 2000

... India KP Pandey 1, Arun Singh, Vinay Kumar and SB Singh GS Sugarcane Breeding and Research In... more ... India KP Pandey 1, Arun Singh, Vinay Kumar and SB Singh GS Sugarcane Breeding and Research Institute, Seorahi, PO Tamkuhi Raj 274 407, Kushinagar, UP, India ... The peak of para-sitism (37.57%) was revealed during first week of Au-gust. ...

Cereal Chem. 73(1):54-57 A 100-g laboratory corn wet-milling procedure was developed in formed du... more Cereal Chem. 73(1):54-57 A 100-g laboratory corn wet-milling procedure was developed in formed during the same week, and 0.60% when replicates were performed order to reduce sample size and labor time requirements for determining weekly during the course of a year. In a properly equipped laboratory, the milling characteristics of corn samples. The procedure gives starch the procedure can be

Toxicology and Applied Pharmacology, 2005

Cyclophosphamide (CPA) is a widely used chemotherapeutic drug in neoplasias. It is a DNA and prot... more Cyclophosphamide (CPA) is a widely used chemotherapeutic drug in neoplasias. It is a DNA and protein alkylating agent that has a broad spectrum of activity against variety of neoplasms including breast cancer. The therapeutic effectiveness of CPA is limited by the high-dose hematopoietic, renal, and cardiac toxicity that accompanies the systemic distribution of liver-derived activated drug metabolites. The present study examines the potential of combining well-tolerated antibiotic doxycycline (DOX) with CPA and understanding the mechanism of cell killing. Interestingly, we found that DOX significantly enhances the tumor regression activity of CPA on xenograft mice model bearing MCF-7 cells. DOX also potentiates MCF-7 cell killing by CPA in vitro. In presence of DOX (3 microg/ml), the IC50 value of CPA decreased significantly from 10 to 2.5 mM. Additional analyses indicate that the tumor suppressor p53 and p53-regulated proapoptotic Bax were upregulated in vivo and in vitro following CPA treatment in combination with DOX, suggesting that upregulation of p53 may contribute to the enhancement of antitumor effect of CPA by DOX. Furthermore, downregulation of antiapoptotic Bcl-2 was observed in animals treated with CPA and CPA plus DOX when compared to untreated or DOX-treated groups. Our results raise the possibility that this combination chemotherapeutic regimen may lead to additional improvements in treatment of breast cancer.

Tectonophysics, 1994

This paper concerns the interplay of compression and extension during Palaeozoic collisional orog... more This paper concerns the interplay of compression and extension during Palaeozoic collisional orogeny in Scandinavia, and focuses on a small Old Red Sandstone basin in the central Scandes at Røragen. Early Devonian sediments are preserved there in a half-graben located in the ...