Comparative genomics of Papaya ringspot virus pathotypes P and W from India

Archives of Virology -     

Development of hollow/porous calcium pectinate beads for floating-pulsatile drug delivery.

The purpose of this work was to develop hollow calcium pectinate beads for floating-pulsatile release of diclofenac sodium intended for chronopharmacotherapy. Floating pulsatile concept was applied to increase the gastric residence of the dosage form having lag phase followed by a burst release. To overcome limitations of various approaches for imparting buoyancy, hollow/porous beads were prepared by simple process of acid-base reaction during ionotropic crosslinking. The floating beads obtained were porous (34% porosity), hollow with bulk density<1 and had Ft50% of 14-24 h. In vivo studies by gamma scintigraphy determined on rabbits showed gastroretention of beads up to 5 h. The floating beads provided expected two-phase release pattern with initial lag time during floating in acidic medium followed by rapid pulse release in phosphate buffer. This approach suggested the use of hollow calcium pectinate microparticles as promising floating-pulsatile drug delivery system for site- and time-specific release of drugs acting as per chronotherapy of diseases.     

A recombinant adenovirus expressing p7(Kip1) induces cell cycle arrest and apoptosis in human 786-0 renal carcinoma cells

PURPOSE: We evaluated the effects of the over expression of p27Kip1, a cyclin dependent kinase inhibitor and tumor suppressor protein, on the 786-0 human renal carcinoma cell line. MATERIALS AND METHODS: The recombinant adenovirus Adp27Kip1 was evaluated for the induction of p27 protein expression in 786-0 renal carcinoma cells. Expression time and optimal vector concentration were determined. Growth curve studies, cell cycle analysis and terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate nick end-labeling were done to determine the effects of p27Kip1 on the cell cycle. Cyclin dependent protein kinase (Cdk) inhibitor (CDKI) activity assays were done to determine the expression/activities of Cdks and Western blot analysis was performed to determine the presence of CDKIs and other cell cycle regulator proteins. Nude mouse xenografts were established to demonstrate the in vivo efficacy of Adp27Kip1. RESULTS: p27Kip1 protein expression was detected within 12 hours after Adp27Kip1 infection and it remained stable for at least 48 hours. Growth studies demonstrated that Adp27Kip1 infection resulted in the inhibition of proliferation by 3 days after infection and cell death was detected by day 5. Cell cycle analysis of DNA content indicated an accumulation of cells in the G1 phase of Adp27Kip1 infected cells and a corresponding decrease in S phase cells within 48 hours after infection. Cdk activity was determined, and Cdk2, Cdk4 and Cdc2 kinase activities were inhibited, consistent with p27Kip1 over expression. The levels of the CDKIs p16 and p18 were elevated 24 hours after Adp27Kip1 infection, while p21 levels remained unchanged. Terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate nick end-labeling revealed that Adp27Kip1 infection but not infection by control virus induced detectable apoptosis within 24 hours. Adp27Kip1 significantly caused the reduction in the size of tumors of the renal cell carcinoma xenografts. CONCLUSIONS: This study demonstrates the potential effectiveness of Adp27Kip1 as a vector for gene therapy studies of renal cell carcinoma.     

Delayed extradural hematoma: a case report

Three patients of delayed extradural hematoma (EDH) were seen in the last one year among forty eight consecutively treated cases of EDH. All the three hematomas were evacuated. Awareness of this entity and a high degree of vigilance are strongly recommended to detect such cases. Repeat CT should always be done, especially after decompression by either surgical or medical means, recovery from shock or whenever there is evidence of even minimal bleeding under a skull fracture on initial CT scan.     

Biomechanical evaluation of a double-threaded pedicle screw in elderly vertebrae

We sought to test the hypothesis that a pedicle screw that has two parallel threads of different heights throughout the full length of the screw could increase both bone purchase and pull-out strength compared with a standard single-threaded screw of similar dimensions. A single-threaded pedicle screw and a double-threaded pedicle screw were respectively placed into the paired pedicles of 21 vertebral bodies. The screws were then pulled out of the pedicles, and output parameters were measured. Although insertional torque was, on average, 14.5% higher (p = 0.039) for the single-threaded screw, maximum pull-out strength (p = 0.12), energy-to-failure (p = 0.39), and stiffness (p = 0.54) were not statistically different for the two screw types. It is concluded that a second, smaller inner thread on a double-threaded pedicle screw does not translate into either increased bone purchase or higher pull-out strengths.     

Neurointensive care in children

Summary Principles of neurointensive care in children with hypoxic encephalopathy have been discussed. The limit of normothermic cardiac arrest after which complete recovery might be achieved seems to be not five minutes but rather between ten and twenty minutes, about the same for the brain and the heart. Cerebral recovery after cardiac arrest can be improved by shortening cardiac arrest and CPR time, maximizing cerebral perfusion pressure during CPR, restoring normotension, and undertaking measures to achieve intra and extracranial homeostasis. Barbiturates and steroids are of no value in treatment of hypoxic encephalopathy in children. Steroids, however, may be used for treatment of cerebral edema resulting from brain tumors.