Biomedical subjects

Alok Sharma

Publications and source records attributed to Alok Sharma.

24 records · Page 2Linked to original sources

PubMed2004

Comparison of methylprednisolone with dexamethasone in treatment of acute spinal injury in rats.

Effect of methylprednisolone sodium succinate (MPSS) and its comparison with dexamethasone in experimentally induced acute spinal cord compression in adult rats was studied. The rats were divided into group A (control) and group B, which was subdivided into B1, B2, B3 where MPSS was given after 1, 8 and 24 hr and B4 where dexamethasone was given after 1 hr of cord injury respectively. Proper neurological evaluation was done with mobility, running and climbing score. Recovery index was evaluated for 7 days. After sacrificing the rats, spinal cord was observed histopathologically. Mean recovery index and microscopic findings based on hemorrhage in gray and white matter, neuronal degeneration, hematomyelia and edema in white matter were recorded. The results suggested that MPSS was effective in promoting post-traumatic clinical and histological recovery and to a greater extent, when given 1 hr after trauma. MPSS is more effective than dexamethasone in reducing edema when both are given after interval of 1 hr.

Animals↗

PubMed2004

Spinal intramedullary arachnoid cyst.

Spinal arachnoid cysts are a relatively uncommon lesion. They may be either intra or extradural; intradural cysts being less common. Symptomatic spinal arachnoid cysts in the pediatric age group are rare. To the best of our knowledge only 2 cases of intramedullary arachnoid cysts have been reported to date. We report an unusual case of intramedullary cyst diagnosed in a 10-year-old female who presented with progressive quadriparesis. MRI scans revealed an intramedullary cystic lesion from C4 to T2. She underwent a C3 to T2 laminectomy with partial excision of the cyst. Histopathological findings confirmed the diagnosis of an arachnoid cyst. Postoperatively the patient showed dramatic recovery with marked improvement in neurological status. Arachnoid cysts should be considered in the differential diagnosis of progressive quadri / paraparesis in the pediatric age group as surgical decompression leads to marked improvement in the symptoms.

Arachnoid Cysts↗

PubMed2003

Functional interaction trap: a strategy for validating the functional consequences of tyrosine phosphorylation of specific substrates in vivo.

Protein tyrosine phosphorylation controls diverse signaling pathways, and disregulated tyrosine kinase activity plays a direct role in human diseases such as cancer. Because activated kinases exert their effects by phosphorylating multiple substrate proteins, it is difficult or impossible to assess experimentally the contribution of a particular substrate to a cellular response or activity. To overcome this problem, we have developed a novel approach termed the "functional interaction trap," in which two proteins are induced to interact in a pairwise fashion through an engineered, highly specific binding interface. We show that the functional interaction trap can be used to direct a modified tyrosine kinase to specifically phosphorylate a single substrate of choice in vivo, permitting analysis of the resulting biological output. This strategy provides a powerful tool for validating the functional significance of tyrosine phosphorylation and other post-translational modifications identified by proteomic discovery efforts.

Animals↗

PubMed2003

Combat of iron-deprivation through a plant growth promoting fluorescent Pseudomonas strain GRP3A in mung bean (Vigna radiata L. Wilzeck).

Microorganisms and plants sustain themselves under iron-deprived conditions by releasing siderophores. Among others, fluorescent pseudomonads are known to exert extensive biocontrol action against soil and root borne phytopathogens through release of antimicrobials and siderophores. In this study, production and regulation of siderophores by fluorescent Pseudomonas strain GRP3A was studied. Among various media tested, standard succinate medium (SSM) promoted maximum siderophore production of 56.59 mg l(-1). There were low levels of siderophore in complex media like King's B medium, trypticase soya medium and nutrient medium (41.27, 29.86 and 27.63 mg l(-1)), respectively. In defferrated SSM, siderophore level was quantified to be 68.74 mg l(-1). Supplementation with iron (FeCl3) resulted in decreased siderophore levels depending on concentration. Siderophore production was promoted by Zn2+ (78.94 mg l(-1)), Cu2+ (68.80 mg l(-1)) whereas Co2+ (57.33 mg l(-1)) and Fe3+ reduced siderophore production (37.44 mg l(-1) as compared to control (55.97 mg l(-1)). Strain GRP3A showed plant growth promotion under iron limited conditions.

Carbon↗

PubMed2003

Growth promoting influence of siderophore-producing Pseudomonas strains GRP3A and PRS9 in maize (Zea mays L.) under iron limiting conditions.

Maize seeds were bacterized with siderophore-producing pseudomonads with the goal to develop a system suitable for better iron uptake under iron-stressed conditions. Siderophore production was compared in fluorescent Pseudomonas spp. GRP3A, PRS9 and P. chlororaphis ATCC 9446 in standard succinate (SSM) and citrate (SCM) media. Succinate was better suited for siderophore production, however, deferration of media resulted in increased siderophore production in all the strains. Maximum siderophore level (216.23 microg/ml) was observed in strain PRS9 in deferrated SSM after 72 h of incubation. Strains GRP3A and PRS9 were used for plant growth promotion experiments. Strains GRP3A and PRS9 were also antagonistic against the phytopathogens, Colletotrichum dematium, Rhizoctonia solani and Sclerotium rolfsii. Bacterization of maize seeds with strains GRP3A and PRS9 showed significant increase in germination percentage and plant growth. Maximum shoot and root length and dry weight were observed with 10 microM Fe3+ along with bacterial inoculants suggesting application of siderophore producing plant growth promoting rhizobacterial strains in crop productivity in calcareous soil system.

Antibiosis↗

PubMedDate not supplied

Endoscopic management of anal protrusion of ventriculo-peritoneal shunt.

A 2-year-old male child, who was operated on 18 months earlier for tuberculous meningitis with hydrocephalus by placement of a ventriculo-peritoneal shunt, presented with the lower end of the shunt tube coming out through the anus. Colonoscopy showed the shunt tube coming out through the colon 22 cm from the anal opening. The cranial end, along with a malfunctioning valve, were disconnected surgically, and the shunt was removed endoscopically using a pediatric flexible colonoscope.

Child, Preschool↗