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author:("sugar, S")
1.  Total colectomy in a gangrenous large bowel due to a rare double closed loop obstruction 
•Dual closed loop obstruction: one due to the sigmoid volvulus and the other due to a competent ileocaecal valve.•Gangrene of the entire large bowel from the ileo caecal junction till the distal end of sigmoid.•Total colectomy done for such necrotizing colitis.•Rapidity of ischaemic changes in a closed loop obstruction.
Closed loop obstruction is commonly encountered in sigmoid volvulus. When such obstruction becomes fulminant, it is called acute necrotizing colitis. Gangrene of the entire large bowel from the caecum till the distal end of the sigmoid is a rare entity.
Presentation of the case
We present here one such case of necrotizing colitis in a 27 years old gentleman who presented with large bowel obstruction and septic shock. Computed tomography (CT) revealed sigmoid volvulus with ischaemic changes. The rest of the colon was dilated. On laparotomy, a gangrenous sigmoid due to the volvulus was found along with complete gangrene of the proximal bowel from the ileocaecal junction till the volvulus. This was probably due to a double closed loop obstruction, one at the sigmoid volvulus and the second being between a probable competent ileocaecal valve and the proximal end of the volvulus. A total colectomy with an end ileostomy was performed.
Necrotising colitis involving the entire colon is seldom seen. Large bowel obstruction is a known surgical emergency due to a probable closed loop obstruction due to a competent ileocaecal valve.
To our knowledge, such gangrene of the entire large bowel due to a sigmoid volvulus and a competent ileocaecal valve has not been reported in literature so far. We also highlight here, the rapid ischaemic changes that follow a closed loop obstruction. In our case the CT has shown ischaemic changes only in the sigmoid. Hence, timely diagnosis and intervention is imperative.
PMCID: PMC4701754  PMID: 26516683
Total colectomy; Large bowel gangrene; Closed loop obstruction; Sigmoid volvulus
2.  Use of image guided radiation therapy techniques and imaging dose measurement at Indian hospitals: A survey 
A national survey was conducted to obtain information about the use of image-guided radiotherapy (IGRT) techniques and IGRT dose measurement methods being followed at Indian radiotherapy centers. A questionnaire containing parameters relevant to use of IGRT was prepared to collect the information pertaining to (i) availability and type of IGRT delivery system, (ii) frequency of image acquisition protocol and utilization of these images for different purpose, and (iii) imaging dose measurement. The questionnaire was circulated to 75 hospitals in the country having IGRT facility, and responses of 51 centers were received. Survey results showed that among surveyed hospitals, 86% centers have IGRT facility, 78% centers have kilo voltage three-dimensional volumetric imaging. 75% of hospitals in our study do not perform computed tomography dose index measurements and 89% of centers do not perform patient dose measurements. Moreover, only 29% physicists believe IGRT dose is additional radiation burden to patient. This study has brought into focus the need to design a national protocol for IGRT dose measurement and development of indigenous tools to perform IGRT dose measurements.
PMCID: PMC4728893  PMID: 26865758
Computed tomography dose index measurements; image guided radiotherapy dose burden to patients; image guided radiotherapy survey
3.  Controlling the metal-to-insulator relaxation of the metastable hidden quantum state in 1T-TaS2 
Science Advances  2015;1(6):e1500168.
Revealing the relaxation mechanisms of hidden states in transition metal dichalcogenides leads to control of metastability.
Controllable switching between metastable macroscopic quantum states under nonequilibrium conditions induced either by light or with an external electric field is rapidly becoming of great fundamental interest. We investigate the relaxation properties of a “hidden” (H) charge density wave (CDW) state in thin single crystals of the layered dichalcogenide 1T-TaS2, which can be reached by either a single 35-fs optical laser pulse or an ~30-ps electrical pulse. From measurements of the temperature dependence of the resistivity under different excitation conditions, we find that the metallic H state relaxes to the insulating Mott ground state through a sequence of intermediate metastable states via discrete jumps over a “Devil’s staircase.” In between the discrete steps, an underlying glassy relaxation process is observed, which arises because of reciprocal-space commensurability frustration between the CDW and the underlying lattice. We show that the metastable state relaxation rate may be externally stabilized by substrate strain, thus opening the way to the design of nonvolatile ultrafast high-temperature memory devices based on switching between CDW states with large intrinsic differences in electrical resistance.
PMCID: PMC4646782  PMID: 26601218
Metastable states; charge density waves; electronic crystals; ultrafast memory devices; nonequilibrium relaxation
5.  Hepatoprotective effect of poly herbal formulation against various hepatotoxic agents in rats 
Pharmacognosy Research  2012;4(1):50-56.
Individually Andrographis paniculata Nees. (Acanthaceae), Phyllanthus niruri Linn.(Euphorbiaceae) and Phyllanthus emblica Linn. single plant extracts have been reported to have hepatoprotective activity. However, literature survey shows that no sufficient scientific data has been publish on pharmacological evaluation of these plants in combined form.
Hepatoprotective activity of the polyherbal hepatoprotaective formulation (PHF)-containing spray-dried aqueous extracts of Andrographis paniculata Nees. (Acanthaceae), Phyllanthus niruri Linn. (Euphorbiaceae) and Phyllanthus emblica Linn. (Euphorbiaceae), was screened against paracetamol, carbon tetrachloride (CCl4), and ethanol-induced hepatic damage in rats. PHF was evaluated by measuring levels of serum marker enzymes like SGOT, SGPT, ALP, direct bilirubin (DB), and lactate dehydrogenase (LDH). The histological studies were also studied support the biochemical parameters. Silymarin was used as standard drug.
Administration of PHF (100 and 200 mg/kg p.o.) significantly inhibited paracetamol, CCl4 and ethanol-induced elevation levels of SGPT, SGOT, ALP, DB and LDH. A comparative histopathological study of liver exhibited almost normal architecture as compared to toxicant group.
Results suggests that the hepatoprotective effects of PHF might be useful for liver protection due to combined action of all plant extracts along with their phytoconstituents.
PMCID: PMC3250040  PMID: 22224062
Andrographis paniculata Nees; carbon tetrachloride; hepatoprotective activity; Marker enzymes; paracetamol; Phyllanthus niruri Linn
6.  Establishment and Molecular Characterization of Mesenchymal Stem Cell Lines Derived From Human Visceral & Subcutaneous Adipose Tissues 
Mesenchymal stem cells (MSCs), are multipotent stem cells that can differentiate into osteoblasts, chondrocytes, myocytes and adipocytes. We utilized adipose tissue as our primary source, since it is a rich source of MSCs as well as it can be harvested using a minimally invasive surgical procedure. Both visceral and subcutaneous adipose tissue (VSAT, SCAT respectively) samples were cultured using growth medium without using any substratum for their attachment. We observed growth of mesenchymal like cells within 15 days of culturing. In spite of the absence of any substratum, the cells adhered to the bottom of the petri dish, and spread out within 2 hours. Presently VSAT cells have reached at passage 10 whereas; SCAT cells have reached at passage 14. Morphologically MSCs obtained from visceral adipose tissue were larger in shape than subcutaneous adipose tissue. We checked these cells for presence or absence of specific stem cell molecular markers. We found that VSAT and SCAT cells confirmed their MSC phenotype by expression of specific MSC markers CD 105 and CD 13 and absence of CD34 and CD 45 markers which are specific for haematopoietic stem cells. These cells also expressed SOX2 gene confirming their ability of self-renewal as well as expressed OCT4, LIF and NANOG for their properties for pluripotency & plasticity. Overall, it was shown that adipose tissue is a good source of mesenchymal stem cells. It was also shown that MSCs, isolated from adipose tissue are multipotent stem cells that can differentiate into osteoblasts, chondrocytes, cardiomyocytes, adipocytes and liver cells which may open a new era for cell based regenerative therapies for bone, cardiac and liver disorders.
PMCID: PMC3908252  PMID: 24693057
Stem cells; mesenchymal stem cells; adipose tissue; molecular markers
7.  In vitro Evaluation of Novel Sustained Release Microspheres of Glipizide Prepared by the Emulsion Solvent Diffusion-Evaporation Method 
The objective of the current investigation is to reduce dosing frequency and improve patient compliance by designing and systematically evaluating sustained release microspheres of Glipizide. An anti-diabetic drug, Glipizide, is delivered through the microparticulate system using ethyl cellulose as the controlled release polymer. Microspheres were developed by the emulsion solvent diffusion-evaporation technique by using the modified ethanol,-dichloromethane co-solvent system. The polymer mixture of ethyl cellulose and Eudragit® S100 was used in different ratios (1:0, 1:1, 2:3, 1:4 and 0:1) to formulate batches F1 to F5. The resulting microspheres were evaluated for particle size, densities, flow properties, morphology, recovery yield, drug content, and in vitro drug release behavior. The formulated microspheres were discrete, spherical with relatively smooth surface, and with good flow properties. Among different formulations, the fabricated microspheres of batch F3 had shown the optimum percent drug encapsulation of microspheres and the sustained release of the Glipizide for about 12 h. Release pattern of Glipizide from microspheres of batch F3 followed Korsmeyers-peppas model and zero-order release kinetic model. The value of ‘n’ was found to be 0.960, which indicates that the drug release was followed by anomalous (non-fickian) diffusion. The data obtained thus suggest that a microparticulate system can be successfully designed for sustained delivery of Glipizide and to improve dosage form characteristics for easy formulation.
PMCID: PMC3035882  PMID: 21331188
Microspheres; Glipizide; ethyl cellulose; Eudragit® S100; emulsion solvent diffusion-evaporation technique; sustained release
8.  Mucoadhesive Bilayered Patches for Administration of Sumatriptan Succinate 
AAPS PharmSciTech  2008;9(3):909-916.
The purpose of this study was to develop and optimize formulations of mucoadhesive bilayered buccal patches of sumatriptan succinate using chitosan as the base matrix. The patches were prepared by the solvent casting method. Gelatin and polyvinyl pyrrolidone (PVP) K30 were incorporated into the patches, to improve the film properties of the patches. The patches were found to be smooth in appearance, uniform in thickness, weight, and drug content; showed good mucoadhesive strength; and good folding endurance. A 32 full factorial design was employed to study the effect of independent variables viz. levels of chitosan and PVP K30, which significantly influenced characteristics like swelling index, in-vitro mucoadhesive strength, in vitro drug release, and in-vitro residence time. Different penetration enhancers were tried to improve the permeation of sumatriptan succinate through buccal mucosa. Formulation containing 3% dimethyl sulfoxide showed good permeation of sumatriptan succinate through mucosa. Histopathological studies revealed no buccal mucosal damage. It can be concluded that buccal route can be one of the alternatives available for administration of sumatriptan succinate.
PMCID: PMC2977019  PMID: 18679806
bioadhesive; buccal patches; chitosan; sumatriptan succinate; 32 factorial design
9.  Comparative analysis of chromatin landscape in regulatory regions of human housekeeping and tissue specific genes 
BMC Bioinformatics  2005;6:126.
Global regulatory mechanisms involving chromatin assembly and remodelling in the promoter regions of genes is implicated in eukaryotic transcription control especially for genes subjected to spatial and temporal regulation. The potential to utilise global regulatory mechanisms for controlling gene expression might depend upon the architecture of the chromatin in and around the gene. In-silico analysis can yield important insights into this aspect, facilitating comparison of two or more classes of genes comprising of a large number of genes within each group.
In the present study, we carried out a comparative analysis of chromatin characteristics in terms of the scaffold/matrix attachment regions, nucleosome formation potential and the occurrence of repetitive sequences, in the upstream regulatory regions of housekeeping and tissue specific genes. Our data show that putative scaffold/matrix attachment regions are more abundant and nucleosome formation potential is higher in the 5' regions of tissue specific genes as compared to the housekeeping genes.
The differences in the chromatin features between the two groups of genes indicate the involvement of chromatin organisation in the control of gene expression. The presence of global regulatory mechanisms mediated through chromatin organisation can decrease the burden of invoking gene specific regulators for maintenance of the active/silenced state of gene expression. This could partially explain the lower number of genes estimated in the human genome.
PMCID: PMC1173084  PMID: 15918906
10.  Optimizing the HIV/AIDS informed consent process in India 
BMC Medicine  2004;2:28.
While the basic ethical issues regarding consent may be universal to all countries, the consent procedures required by international review boards which include detailed scientific and legal information, may not be optimal when administered within certain populations. The time and the technicalities of the process itself intimidate individuals in societies where literacy and awareness about medical and legal rights is low.
In this study, we examined pregnant women's understanding of group education and counseling (GEC) about HIV/AIDS provided within an antenatal clinic in Maharashtra, India. We then enhanced the GEC process with the use of culturally appropriate visual aids and assessed the subsequent changes in women's understanding of informed consent issues.
We found the use of visual aids during group counseling sessions increased women's overall understanding of key issues regarding informed consent from 38% to 72%. Moreover, if these same visuals were reinforced during individual counseling, improvements in women's overall comprehension rose to 96%.
This study demonstrates that complex constructs such as informed consent can be conveyed in populations with little education and within busy government hospital settings, and that the standard model may not be sufficient to ensure true informed consent.
PMCID: PMC509426  PMID: 15287983

Results 1-10 (10)