PubMed Health⌕ Search

Biomedical subjects

Rohit Sharma

Publications and source records attributed to Rohit Sharma.

At least 19 recordsLinked to original sources
PubMed2006

Screening for retinopathy of prematurity in developing countries.

Improved survival of low birth weight, premature babies in India has increased the incidence of retinopathy of prematurity. Western reports describe screening criteria to pick up babies most at risk. However, our population of at-risk neonates is likely to be different, as most nurseries in India are not very well equipped. Our aim was to develop a screening strategy appropriate for our conditions. Ophthalmic records of 60 neonates with gestational age < or =35 weeks and/or birth weight < or =1500 g, born over a 1-year period, were retrospectively reviewed. Laterality, location and stage of retinopathy of prematurity were recorded. Age at detection, at threshold disease and at maximum stage was recorded, and progression or regression of retinopathy noted. The incidence of retinopathy was 13/60 (21.7%) and of threshold disease was 3/60 (5.0%). Threshold disease was never seen before 5.5 weeks PNA. Zone I disease invariably, zone II disease in 12.5% cases and zone III disease never progressed to threshold stage. Most (10/13; 76.9%) cases regressed without treatment. Screening for retinopathy should commence at 4 weeks PNA (post-neonatal age). Screening time, discomfort to the baby and complications can be reduced by examining temporal retina first. If normal, the nasal retina need not be examined. Also, babies with zone III disease need not be followed up to complete visualization. Retinal vascular dilatation, resistance to pupillary dilation and persistence of tunica vasculosa lentis can be indicators of intensive screening.

Age Factors↗
PubMed2006

Nonconvulsive seizures in the pediatric intensive care unit: etiology, EEG, and brain imaging findings.

PURPOSES: To determine the occurrence of nonconvulsive seizures (NCS) in the Pediatric Intensive Care Unit (PICU); to ascertain the relationship of NCS to past medical history, etiology, EEG, and brain imaging; and to determine the concordance between abnormal EEG findings and neuroimaging abnormalities. METHODS: A retrospective review was conducted of all pediatric patients who were admitted or transferred to the PICU from January 2000 to December 2003 with an unexplained decrease in level of consciousness, no overt clinical seizures, and EEG recordings performed within the 24 h of onset of an altered state of consciousness. RESULTS: Twenty-three of 141 patients who met criteria for inclusion in the study (16.3%) were found to have NCS. The male to female ratio was 1.9:1. The largest group of patients (43%) had no preexisting neurological condition prior to the onset of NCS. In the remainder, the etiology of NCS included: acute structural brain lesion (48%), acute nonstructural brain lesion (22%), epilepsy-related seizure (13%), and others (17%). Epileptic foci were lateralized to the right side in 39.2%, the left side in 30.4%, and were bilateral in 30.4%. Of 23 patients with NCS, 18 (78.3%) demonstrated abnormal neuroimaging. In 10 of 18 of these patients (55.6%), the findings on neuroimaging were concordant with the lateralization found on EEG (p < 0.05, Fisher's exact test). CONCLUSIONS: NCS are not uncommon in pediatric patients with an altered state of consciousness. Almost half of the patients were previously healthy especially if they were under 6 months of age. This report highlights the importance of clinical awareness of NCS in the PICU.

Brain↗
PubMed2006

An unusual presentation of desmoid tumor in the ileum.

Desmoid tumors are nonencapsulated, locally invasive tumors of fibrous origin. Although lacking the ability to metastasize, they are notorious for recurrence. A wide variety of locations have been documented in the literature with respect to the origin of these tumors. Intra-abdominal desmoids are commonly found in the mesentery. We present the report of a case in which a sporadic desmoid tumor originated from the wall of the ileum. The patient was successfully treated with surgery alone, and has remained recurrence free on follow-up. Modalities of treatment documented in the literature include surgery, nonsteroidal, anti-inflammatory drugs such as sulindac, and chemotherapeutic drugs such as vinblastine and methotrexate, radiotherapy, and, recently, tyrosine kinase inhibitors such as Imatinib (gleevec). Of all the options described, surgery with tumor-free margins has been defined as the best treatment modality.

Adult↗
PubMed2005

Volumetric localization of epileptic activities in tuberous sclerosis using synthetic aperture magnetometry.

BACKGROUND: Magnetoencephalography (MEG) is a novel noninvasive technique for localizing epileptic zones. Tuberous sclerosis complex (TSC) is often associated with medically refractory epilepsy with multiple epileptic zones. Surgical treatment of TSC requires accurate localization of epileptogenic tubers. OBJECTIVE: The objective of this study was to introduce a new MEG technique, synthetic aperture magnetometry (SAM), to volumetrically localize irritable zones and clarify the correlations between SAM, dipole modeling and anatomical tubers. MATERIALS AND METHODS: Eight pediatric patients with TSC confirmed by clinical and neuroimaging findings were retrospectively studied. MEG data were recorded using a whole-cortex CTF OMEGA system. Sleep deprivation was employed to provoke epileptiform activity. Irritable zones were localized using both dipole modeling and SAM. RESULTS: MRI detected 42 tubers in the eight patients. Dipole modeling localized 28 irritable zones, and 19 out of the 28 zones were near tubers (19/42, 45%). SAM found 51 irritable zones, and 31 out of the 51 zones were near tubers (31/42, 74%). Among the 51 irritable zones determined by SAM, thirty-five zones were in 1-35 Hz, nine zones were in 35-60 Hz, and seven zones were in 60-120 Hz. CONCLUSIONS: The new method, SAM, yielded very plausible equivalent sources for patients who showed anatomical tubers on MRI. Compared to conventional dipole modeling, SAM appeared to offer increased detection of irritable zones and beneficial volumetric and frequency descriptions.

Brain Mapping↗
PubMed2005

Reactive EEG patterns in pediatric coma.

This study was designed to determine whether the observed reactive electroencephalographic patterns in comatose children were associated with a better outcome. All electroencephalograms performed in comatose children aged 2 months to 18 years during the period 1996-2003 were retrospectively analyzed and classified according to modified Young's classification. Reactivity to painful/auditory stimuli and passive eye closure (at least two modalities) was checked in all electroencephalograms. The clinical outcome at 1 year or during the last clinic/inpatient follow-up was scored according to the Pediatric Cerebral and Overall Performance Category Scale. Outcomes were then compared using Fisher exact test and the Mann-Whitney test. Thirty-three patients had electroencephalography within 72 hours after the onset of coma. Fourteen of 33 electroencephalograms revealed reactive patterns. Outcome was unfavorable in 4 (28.6%) of these patients. Three children had no residual neurologic impairment. Among the 19 children with nonreactive electroencephalogram, 13 (65%) had unfavorable outcome, which included 10 deaths. All the survivors had residual neurologic impairment. Outcome was better in children with reactive electroencephalographic patterns (Fisher exact test; P = 0.023). Comatose children with reactive electroencephalographic patterns have better clinical outcome in terms of morbidity and mortality. A careful assessment of electroencephalographic reactive patterns in all comatose children is required for better understanding of the clinical outcome.

Adolescent↗
PubMed2005

A reappraisal of rhythmic coma patterns in children.

OBJECTIVE: This study was designed to determine the prevalence of rhythmic coma patterns in comatose children and to ascertain the prognostic significance of reactive rhythmic coma patterns. METHODS: We retrospectively analyzed and classified electroencephalogram (EEGs) in comatose children between two months and 18 years of age during the period 1996 - 2003 according to modified Young's classification. Outcome at one-year was scored according to the Paediatric Cerebral and Overall Performance Category Scale. Outcomes were compared using Fisher's exact test and Mann-Whitney test. RESULTS: Analysis of 63 electroencephalogram (EEG) records in 38 patients showed rhythmic patterns in 19 records (30.2%; 9 alpha, 4 spindle, 4 theta and 2 beta coma patterns, total number of children = 14). Aetiology and outcome of alpha coma patterns and other rhythmic coma patterns were similar. In five children, one type of rhythmic pattern changed to another. Records with reactive rhythmic coma 66.7% (6/9), were associated with favourable outcome. Sixty percent of the records (6/10 records in seven children) with non-reactive pattern were associated with unfavourable outcome. This clinically significant difference did not reach statistical significance (lower Paediatric Cerebral and Overall Performance Category Scale score p= 0.14; favourable outcome p=0. 19). CONCLUSION: Rhythmic coma patterns in comatose children are not uncommon. Aetiology, reactivity and outcome of individual patterns are similar and thus make the rhythmic coma patterns distinct EEG signatures in comatose children. There was a clinically significant better outcome with reactive rhythmic coma patterns.

Adolescent↗
PubMed2005

Fetal monitoring in labor: are accelerations good enough?

OBJECTIVE: To investigate whether accelerations of the fetal heart rate in response to scalp stimulation (the scalp stimulation test) before fetal scalp blood sampling (FBS) are such a good predictor of fetal well-being as to render the FBS unnecessary. METHODS: A retrospective observational study. Cardiotocograms (CTG) from 54 fetuses during labor in whom 70 FBS procedures were performed, were analysed by an investigator blinded to the outcome, to determine whether accelerations were present in response to fetal scalp stimulation during vaginal examination (VE) prior to the FBS. This was compared with the pH obtained at FBS in a 2 x 2 table. The primary outcome measure was the false negative rate of the scalp stimulation test. RESULTS: There were accelerations at 48 VEs before FBS (n = 70). In five cases there was fetal acidosis (pH<or=7.20). Three of these five fetuses had accelerations at VE, giving a false negative rate of 6.25%. CONCLUSION: These data do not support previous reports that accelerations in response to fetal scalp stimulation before FBS exclude fetal acidosis when the CTG is suspicious and FBS is otherwise indicated. A larger sample may help answer this question.

Acidosis↗
PubMed2004

Retinopathy of prematurity--risk factors.

OBJECTIVE: Improved survival of low birth weight, premature babies have increased the incidence of retinopathy of prematurity. This hospital-based, prospective, study was undertaken to determine its incidence and risk factors in our neonatal unit. METHODS: Neonates with gestational age < or = 35 weeks and/or birth weight < or = 1500 gm born over a one-year period were examined by indirect ophthalmoscopy between 2 to 4 weeks after birth, and followed up till retinal vascularisation was complete. Maternal and neonatal risk factors were noted and data analyzed by statistical package SPSS-10.0. RESULTS: Sixty babies were thus examined. The incidence of retinopathy was 21.7% in the cohort, 33.3% in babies < or = 32 weeks gestation and 36.4% in babies weighing < or = 1250 gm. Oxygen (p=0.01), sepsis (p=0.04) and apnoea (p=0.02) were independent risk factors. Retinopathy was significantly more severe in babies with hyaline membrane disease (p=0.02) and lower birth weight (p=0.02). Severe disease was never seen before 6.5 weeks of age. CONCLUSION: Indirect ophthalmoscopy should be performed at 4 weeks of post natal age in all preterm babies with birth weight < or = 1500 gm, and intensified in the presence of risk factors like oxygen administration, apnoea and septicemia.

Apnea↗
PubMed2004

Determination of gibberellins in fermentation broth produced by Fusarium verticilliodes MTCC 156 by high-performance liquid chromatography tandem mass spectrometry.

A method for the detection of gibberellins produced by Fusarium verticilliodes is described using HPLCMS/MS (HPLC tandem MS). A Hypersil (5 microm) octadecylsilane column with methanol/water as eluent in the ratio 3:1 at a flow rate of 0.5 ml/min was used. In the HPLCMS, GA(3) (gibberellic acid; m / z 346.3) eluted at retention time tr=3.08 min, with the corresponding mass chromatogram having peaks at m / z 346.7 and 328.8 corresponding to the M+ and M+-H2O ions respectively. The ethyl acetate extract from the broth, subjected to HPLCMS analysis under similar conditions, showed a constituent with tr=2.13 min, the mass chromatogram of which exhibited peaks at m / z 348.9 and 331.9 corresponding to the MH+ and MH+-H2O ions respectively. Comparison of the MS and MS/MS results (direct infusion) of an authentic sample of GA3 and the ethyl acetate extract from the broth revealed the formation of reduced GA3 in the broth. The present study, utilizing HPLCMS/MS, describes an improved methodology for the unambiguous determination and estimation of gibberellins from fermentation broth.

Chromatography, High Pressure Liquid↗
PubMed2004

Three-dimensionally reconstructed magnetic source imaging and neuronavigation in pediatric epilepsy: technical note.

OBJECTIVE: To determine the role of reconstructing three-dimensional magnetic source imaging (MSI) data on cortical resections for children undergoing epilepsy surgery using neuronavigation. METHODS: Magnetoencephalographic recordings were analyzed in 16 children under 18 years of age with intractable epilepsy. The data were transferred to the neuronavigation workstation for intraoperative localization of MSI spike sources in selected patients. With the aid of neuronavigation, the MSI spike sources were resected. Intraoperative electrocorticography was then used to survey the surrounding field for residual epileptiform activity. RESULTS: MSI spike sources were obtained in 13 of 16 patients. MSI spike sources localized the cortical and subcortical discharges before intraoperative electrocorticography in nine patients and before extraoperative subdural grid electroencephalographic monitoring in four patients. The localization of MSI spikes sources was characterized by clustered spike sources in 10 patients. By use of neuronavigation, the clustered spike sources were correlated to the interictal zone indicated by intraoperative electrocorticography in six patients and to the ictal onset zone shown on extraoperative subdural grid electroencephalography in three patients. Cortical excision of the spike cluster focus was then performed in these six patients. The technique used here to resect MSI spike source clusters that correlate with the ictal onset zone by invasive subdural grid monitoring is illustrated in one patient who underwent cortical resection for epilepsy surgery. CONCLUSION: Three-dimensional reconstruction of MSI data linked to neuronavigation is a promising technique to facilitate resections around eloquent cortex in children with epilepsy.

Adolescent↗
PubMed2003

Volumetric localization of somatosensory cortex in children using synthetic aperture magnetometry.

BACKGROUND: Magnetic signal from the human brain can be measured noninvasively by using magnetoencephalography (MEG). OBJECTIVE: This study was designed to localize and reconstruct the neuromagnetic activity in the somatosensory cortex in children. MATERIALS AND METHODS: Twenty children were studied using a 151-channel MEG system with electrical stimulation applied to median nerves. Data were analyzed using synthetic aperture magnetometry (SAM). RESULTS: A clear deflection (M1) was clearly identified in 18 children (90%, 18/20). Two frequency bands, 30-60 Hz and 60-120 Hz, were found to be related to somatosensory cortex. Magnetic activity was localized in the posterior bank of the central sulcus in 16 children. The extent of the reconstructed neuromagnetic activity of the left hemisphere was significantly larger than that of the right hemisphere ( P<0.01). CONCLUSION: Somatosensory cortex was accurately localized by using SAM. The extent of the reconstructed neuromagnetic activity suggested that the left hemisphere was the dominant side in the somatosensory system in children. We postulate that the volumetric characteristics of the reconstructed neuromagnetic activity are able to indicate the functionality of the brain.

Adolescent↗
PubMed2003

A rapid and sensitive fluorometric assay method for the determination of nitrilase activity.

A rapid, simple and sensitive fluorometric assay method for the determination of nitrilase activity is described. 3-Cyanopyridine was hydrolysed to nicotinic acid by Rhodococcus rhodochrous and the liberated NH(3) was allowed to react with buffered o -phthaldialdehyde-2-mercaptoethanol solution (pH 7.4) to form a fluorochrome. The fluorescence intensity was found to be stable after 20 min incubation at room temperature, and the optimum pH for the reaction was found to be 7.4. The fluorescence intensity was linearly related to enzyme activity with the substrate concentration ranging from 100 to 1000 mM. The activity determined by the proposed method correlates ( r =0.9625) well with the established Berthelot method. The proposed method is more sensitive than the existing methods for the determination of nitrilase activity.

Aminohydrolases↗
PubMed2003

A high-throughput amenable colorimetric assay for enantioselective screening of nitrilase-producing microorganisms using pH sensitive indicators.

Based on the color change of an indicator due to the release of hydrogen ion from a nitrilase-catalyzed reaction, a rapid colorimetric method was established for the enantioselective screening of nitrilase-producing microorganisms. The formation of acids due to the nitrilase-mediated hydrolysis of nitriles causes a drop in the pH, which in turn results in a change of color of the solution (containing indicator) that can be observed visually. The buffer (0.01 M phosphate, pH 7.2) and indicator (Bromothymol blue, 0.01%) were selected in such a way that both have the same affinity for the released protons. The enantioselectivity of nitrilases was estimated by comparing the hydrolysis of (R)-mandelonitrile with that of racemate under the same conditions. The method was used to screen a library of nitrilase-producing microorganisms, isolated in the authors' laboratory for their ability to enantioselectively hydrolyze mandelonitrile to mandelic acid, an important chiral building block.

Acetonitriles↗
PubMed2003

Odontogenic myxoma of the mandible: a case report.

A case of myxoma of mandible in a 23 years old female patient is described. The case was treated with enbloc resection and bone graft from iliac crest. No recurrence is reported after 4 years follow up.

Adult↗