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Biomedical subjects

V K Jain

Publications and source records attributed to V K Jain.

At least 19 recordsLinked to original sources

Chiari I malformation associated with atlanto-axial dislocation: focussing on the anterior cervico-medullary compression.

BACKGROUND: Chiari I malformation with atlantoaxial dislocation may cause both posterior and anterior cervicomedullary compression. We studied the clinicoradiological features and surgical outcome in patients having Chiari I malformation with atlantoaxial dislocation. METHOD: Thirty-nine patients with Chiari I malformation with atlanto-axial dislocation underwent preoperative and follow-up neurological status assessment. In Chiari I malformation with reducible atlanto-axial dislocation (n = 11), a direct posterior stabilization was done. In Chiari I malformation with irreducible atlanto-axial dislocation (n = 28), a single stage transoral decompression with posterior stabilization and/or posterior decompression and duraplasty were done in 18 patients. In 10 patients, only posterior decompression and/or posterior stabilization was performed. Seven among the latter patients subsequently deteriorated and required transoral decompression. Comparison of mean neurological status scores of patients with Chiari I malformation with irreducible atlanto-axial dislocation who underwent single stage transoral decompression with posterior stabilization versus the posterior procedure alone was done using T-test and proportional significance also calculated. FINDINGS: Patients with Chiari I malformation with atlanto-axial dislocation have a high incidence of long tract signs and sphincteric disturbances with a decrease in the mean foramen magnum diameter. The mean neurological status scores of patients with Chiari I malformation with irreducible atlanto-axial dislocation who underwent single stage transoral decompression with posterior stabilization were significantly better than those patients who underwent the posterior procedure alone. The latter patients also showed significant clinical improvement following transoral decompression. In the presence of Chiari I malformation with reducible atlanto-axial dislocation, reduction and stabilization of atlanto-axial dislocation resulted in neurological improvement. The follow up neurological status scores of these patients improved after surgical intervention even in the presence of poor preoperative grades. CONCLUSIONS: Patients with Chiari I malformation should be investigated for the presence of atlanto-axial dislocation. In case atlantoaxial dislocation coexists, priority must be given to relieving anterior cervicomedullary compression.

Adolescent↗

Identification of polycyclic aromatic hydrocarbons (PAHs) in suspended particulate matter by synchronous fluorescence spectroscopic technique.

The synchronous fluorescence (SF) technique has been used in the identification of polycyclic aromatic hydrocarbons (PAHs) from air particulate sample in an urban environment of Delhi, Jawaharlal Nehru University. Suspended particulate matter samples of 24h duration were collected on glass fiber filter papers. PAHs were extracted from the filter papers using dichloromethane (DCM)+hexane with ultrasonication method. Qualitative measurements of the polycyclic aromatic hydrocarbons (PAHs) were carried out using the SF technique at various wavelength intervals (Deltalambda). Due to the difference in chemical structure, each PAH gives specific characteristic spectrum for each Deltalambda. Following PAHs were detected in our measurement: benz(a)anthracene (BaA), pyrene (Pyr), chrysene (Chry), fluoranthene (Flan), phenanthrene (Phen), and benz(ghi)perylene (BghiP). This is in agreement with our earlier work for determination of these PAHs using gas chromatography (GC). The seasonal variation of the PAHs was found to be maximum in winter and minimum during the monsoon.

Air Pollutants↗

Seasonal trends in coarse and fine particle sources in Delhi by the chemical mass balance receptor model.

A study of the source contribution of atmospheric particulate matter and associated heavy metal concentrations using chemical mass balance model Version 8 (CMB8) in coarse and fine size mode has been carried out for the city of Delhi. Urban particles were collected using a five-stage impactor at six sites in three different seasons, viz. winter, summer and monsoon in the year 2001. Five samples from each site in each season were collected. The results obtained indicate the dominance of vehicular pollutants in fine size mode, whilst the contribution in coarse mode to some extent is site specific but largely due to vehicular pollution and, soil and crustal dust. Seasons also play an important role but in coarse size fraction only.

Air Pollutants↗

Characterization and source identification of polycyclic aromatic hydrocarbons (PAHs) in the urban environment of Delhi.

This paper reports on polycyclic aromatic hydrocarbons (PAHs) in the atmospheric particulate matter of Jawaharlal Nehru University campus, an urbanized site of New Delhi, India. Suspended particulate matter samples of 24h duration were collected on glass-fiber filter paper for four representative days in each month during January 2002 to December 2003. PAHs were extracted from filter papers using toluene with ultrasonication method and analysed. Quantitative measurements of polycyclic aromatic hydrocarbons (PAHs) were carried out using the gas chromatography technique. The annual average concentration of total PAHs were found to be 668+/-399 and 672+/-388 ng/m3 in the years 2002 and 2003, respectively. The seasonal average concentrations were found to be maximum in winter and minimum during in the monsoon. The results of principal component analysis (PCA) indicate that diesel and gasoline driven vehicles are the principal sources of PAHs in all the seasons. In winter coal and wood combustion also significantly contribute to the PAH levels.

Air Pollutants↗

Intracranial aneurysms in patients 18 years of age or under, are they different from aneurysms in adult population?

BACKGROUND: Intracranial aneurysms are extremely uncommon in the first two decades of life. This study was undertaken to assess the clinicoradiological features and surgical outcome of intracranial aneurysms in patients less than or equal to 18 years of age; and, to highlight the differences between these and intracranial aneurysms seen in adult patients. METHODS AND MATERIAL: Twenty-two patients, 18 years of age or under (male:female ratio=1.75:1; mean age 14.18+/-3.8 years, age range 5 to 18 years) and 451 adult patients aged older than 18 years (male:female ratio=1:1.05; mean age 48.21+/-12.71 years, age range, 19 to 81 years) were treated for intracranial aneurysms at our center between January 1991 and July 2003. The univariate statistical analysis was used to compare differences between the two groups. FINDINGS: The patients under 18 years constituted 4.6% of the total patient population having intracranial aneurysms. The incidence of associated medical diseases was greater in patients under 18 years than in the adults (9% versus 0.26%, p<0.05). The incidence of seizures was more than double in patients under 18 years (36% versus 17%, p<0.05). The incidence of intracerebral haematoma (ICH; 41% versus 22.5%, p>0.05), intraventricular haemorrhage (IVH; 45% versus 34%, p>0.05), and hydrocephalus (36% versus 25%, p>0.05) were higher in patients under 18 years. In adult patients, anterior communicating artery (AcoA) and in children, ICA bifurcation were the most frequent sites of aneurysm formation respectively (p<0.05). The incidence of giant aneurysms was nearly double in children (13.6% versus 6.5%, p>0.05). The incidence of clinical vasospasm was almost the same in both groups. The overall outcome was favourable in 82% of patients under 18 years and 58.8% in adults. The management mortality in patients under 18 years was 9.1%, while in the adult patients, it was 19%. CONCLUSION: In patients under 18 years of age, there was a definite male predominance; a higher incidence of seizures; and, the ICA bifurcation formed the most frequent site of intracranial aneurysms. In adults, AcoA a was the commonest site. Rebleeding and delayed ischaemic deficits were the major causes of morbidity. Favorable outcome after surgery in young patients was better in comparison to their adult counterparts.

Adolescent↗

A study to characterize the influence of outdoor SPM and associated metals on indoor environment in Delhi.

In order to understand the influence of outdoor SPM and its associated metals on indoor environment, a study was carried out for 24 residential, sensitive, commercial and heavy traffic sites in Delhi. In the first phase, the samplings of SPM were conducted simultaneously indoors and outdoors at a reference site during February to March 2000 and later at all other sites from February to July 2001. Atomic Absorption Spectrometry (AAS) was used to determine the heavy metal composition of SPM, analyses of Ca, Mg, Cu, Cd, Pb, Cr, Mn, Fe and Ni were done. It is observed that, depending upon the nature of the site, the outdoor SPM concentrations affect the indoor SPM concentrations in varying degrees. In case of metals such as Cu, Cr, Cd and Ni, very good correlation between the indoor and outdoor concentrations was observed irrespective of the nature of the site. The correlation between indoor and outdoor for Mg, Fe, Mn and Pb depends upon the nature of the site. No correlation was observed between indoor and outdoor Ca at any of the chosen sites.

Air Pollutants↗

Forecasting daily maximum surface ozone concentrations in Brunei Darussalam--an ARIMA modeling approach.

A time series approach using autoregressive integrated moving average (ARIMA) modeling has been used in this study to obtain maximum daily surface ozone (O3) concentration forecasts. The order of the fitted ARIMA model is found to be (1,0,1) for the surface O3 data collected at the airport in Brunei Darussalam during the period July 1998-March 1999. The model forecasts of one-day-ahead maximum O3 concentrations have been found to be reasonably close to the observed concentrations. The model performance has been evaluated on the basis of certain commonly used statistical measures. The overall model performance is found to be quite satisfactory as indicated by the values of Fractional Bias, Normalized Mean Square Error, and Mean Absolute Percentage Error as 0.025, 0.02, and 13.14% respectively.

Air Pollutants↗

C3-4 level cervical spondylotic myelopathy.

Cervical spondylotic myelopathy (CSM) is uncommon at the C3-4 level. Fourteen patients with C3-4 CSM were treated over a period of 3 years. The radiological factors contributing to CSM at the C3-4 level were studied. These factors included the assessment of static and dynamic canal diameters, retrolisthesis, posterior osteophytes and degenerative spinal segmental fusion on plain X-rays; and, the antero-posterior cord compression ratio (APCR) on magnetic resonance imaging (MRI). The clinical status of the patients was assessed by the modified Japanese orthopedic association scale (mJOAS). The mean difference between the static and dynamic canal diameters was statistically significant at C3-4 (p < 0.01). The APCR obtained at different levels showed a significant compression at the C3-4 level in comparison to the lower level. There was a correlation between the APCR and the preop mJOAS, r=0.6 (p< 0.05). The mean mJOAS improved from 9.35 to 14.35 at follo-up. The recovery rate calculated using the modified Hirabayashi rate was 66.9%. Degenerative changes at lower cervical segments predispose to increased mobility and spondylotic changes at the C3-4 level. The patients in this study were young as compared to those reported in the international literature.

Cervical Vertebrae↗

Chiari I malformation related syringomyelia: radionuclide cisternography as a predictor of outcome.

BACKGROUND: This prospective study, conducted in patients with Chiari I malformation (C I) related syringomyelia who underwent posterior decompression and duroplasty, utilizes radionuclide cisternography in order to study the cerebrospinal fluid (CSF) dynamics at the foramen magnum and to predict the clinical outcome following surgery. METHODS: 17 consecutive patients of C I with syringomyelia (but without hydrocephalus or fixed atlanto-axial dislocation), underwent a detailed neurological examination and were assigned a clinical disability score based on the modified Klekamp and Samii score. A radionuclide cisternography (using Tc99m-DTPA) was performed via the lumbar route and the ascent of the tracer was followed utilizing a gamma camera immediately after injection and then sequentially after 1, 2, 4, 6 and 24 hours. After posterior decompression and duroplasty, the modified Klekamp and Samii score was repeated at follow-up visits (range: 3 months to one year) along with radionuclide cisternography at 3 months, and MR imaging at 6 months. FINDINGS: Three patterns of tracer flow were observed: a). rapid flow (n=7); b). supratentorial subarachnoid delay (n=7); and, c). foramen magnum block (n=3). The patients having foramen magnum block had the poorest clinical scores on admission. At follow up, there was an improvement in the clinical scores so that the mean scores in all three categories reached nearly the same level. Following posterior decompression, the radionuclide cisternography performed in 10 patients showed a rapid flow of the tracer without any obstruction. The syrinx resolved in 4 of the 11 patients in whom an MRI was done. INTERPRETATION: The patients with C I with syringomyelia may often have a free flow of tracer across the FM. Posterior decompression and duroplasty provides maximum clinical relief in patients with a demonstrable foramen magnum block on radionuclide cisternography while those with a normal flow have less relief. The symptomatology related to brain-stem compression immediately responds to the surgical procedure but the syrinx-induced signs and symptoms of spinal cord dysfunction persist.

Adolescent↗

Congenital reducible atlantoaxial dislocation: classification and surgical considerations.

BACKGROUND: Reducible atlanto-axial dislocation (AAD) may cause severe motor and respiratory compromise due to recurrent spinal cord and/or brain stem impingement. To the best of the authors' knowledge, this is the first study concentrating on the classification, the protocol of the surgical management and the outcome of congenital, reducible AAD. METHODS: 109 patients with congenital, reducible AAD underwent posterior stabilization. Their preoperative disability was graded as: I (n=11, 10.09%) no functional disability (a history of minor trauma led to quadriparesis that subsequently improved); II (n=31, 28.44%) independent for activities of daily living with minor disability; III (n=42, 38.53%) partially dependent on others for their daily needs; and, IV (n=25, 22.93%) totally dependent. They were classified into 4 groups depending upon their association with: a normal odontoid and posterior arch of atlas (n=27); a dysplastic odontoid and normal posterior arch (n=25); an assimilated posterior arch (n=49); and, Arnold Chiari malformation type I (n=8). Nine patients with a dysplastic odontoid had a "hypermobile" AAD with an unrestricted backward and forward movement of the axis relative to the atlas in flexion as well as in extension of the neck, respectively. The surgical procedures included Brooks' (n=12) or modified Brooks' C1-2 fusion (n=39); Goel's C1-2 fusion (3); Ransford's contoured rod fusion (n=7); Jain's occipitocervical fusion (n=47); and, transoral decompression and Jain's occipitocervical fusion (n=1). There were 6 peri-operative mortalities in the series. FINDINGS: At follow-up (ranging from 3 months to 6 years; n=86), 64 patients had shown improvement by one grade or more; 8 patients, who had a history of transient quadriparesis but were without neurological deficits at presentation, remained in grade I; 11 had achieved stabilization of neurological functions; while 3 had deteriorated despite adequate radiological reduction of AAD and fusion of the construct. A follow-up of 6 months or more was available in 79 of these 86 patients, in whom a dynamic intrathecal CT scan showed a good osseous union. INTERPRETATION: The patients with congenital reducible AAD, depending on their surgical management, may be classified into four groups. Some patients with a dysplastic odontoid have a "hypermobile" AAD and require special care during intubation, positioning and stabilization. An assimilated posterior arch is often associated with asymmetrical lateral occipito-C1-C2 joint synostosis rendering transarticular screw placement difficult. The various causes of failure of constructs are discussed.

Adolescent↗

Embolization of cranial/spinal tumours and vascular malformations with hydrogel microspheres. An experience of 69 cases.

OBJECTIVE: To evaluate polymethyl methacrylate hydrogel microspheres (HMs) as an embolization material in the management of hypervascular craniofacial and spinal lesions. MATERIAL AND METHODS: Sixty-nine patients with vascular lesions of the craniofacial and spinal regions underwent embolization with HM. The pathologies included craniofacial tumours (n=38), cranial arteriovenous malformations (AVMs) (n=7), dural AVM (n=1), cavernous carotid fistula (n=1), spinal tumours (n=7), spinal AVMs (n=6), orbital lesions (n=4) and scalp AVMs (n=5). Surgery was done in 56 patients. The blood loss at surgery, tumour shrinkage, surgical cleavage and ease of removal of tumour was noted from the records. Histopathology was available in 39 patients. A follow-up of 3 months to 6 years was available in 13 patients in whom embolization was the sole treatment. Surgical and histopathological findings were correlated with angio-embolization findings. RESULTS: HMs were easy to inject through the microcatheter with good control. Good devascularization was obtained in 61 patients and partial in 8 patients. Two patients developed complications due to presence of anastomoses between intra- and extracranial circulation and 1 patient due to tumor swelling. Histopathology showed presence of HMs in all the lesions, with minimal inflammatory reaction in 2 patients. Patients with spinal lesions treated with embolization only stabilised in neurologic deficits. CONCLUSION: HMs are highly suitable as embolization agents in the management of craniofacial and spinal hypervascular lesions.

Antimutagenic Agents↗

Migraine-like visual hallucinations in occipital lesions of cysticercosis.

Four Indian patients with occipital lesions of cysticercosis presented with visual hallucinations. Neuro-ophthalmic and systemic examinations were normal in all cases except for one patient who had a partial homonymous hemianopia. Electroencephalography was normal in all cases. Neuroimaging revealed ring-enhancing lesions in the occipital lobe typical of neurocysticercosis. In endemic regions like India, neurocysticercosis should be suspected in patients presenting with visual hallucinations, even when there are no other clinical findings.

Adolescent↗

Patch testing in discoid eczema.

Fifty patients of both sexes with clinically suspected discoid eczema were patch tested with the Indian Standard Patch Test Battery approved by the Contact and Occupational Dermatosis Forum of India (CODFI). Most of these patients were young adults between 20 and 39 years old, with a mean age of 36 years. The mean duration of symptoms was 21/2 years. The occupational profiles of the patients included farmers (24%), housewives (18%), students (14%), housewives engaged in farming (12%), shopkeepers (10%), and laborers (8%). The miscellaneous group, including technicians, drivers, cable operators, office workers, and computer operators, accounted for the remaining 14%. The common clinical patterns of presentation of discoid eczema included hands and feet (44%), hands and forearms' (30%), legs and feet (12%) and trunk and limbs (12%). Patch test analysis of these patients revealed that, out of the 50 subjects tested, 28 (56%) reacted to one or more allergens. Potassium dichromate was the most common allergen (20%), followed by nickel (16%), cobalt chloride, and fragrance (12% each) in decreasing order of frequency. Hence, it may be concluded that patch testing should be considered for all patients with severe or persistent discoid eczema because allergic contact dermatitis may be relatively common in such patients and the avoidance of offending allergens may be of substantial benefit to the patients.

Adolescent↗

Bilateral groove sign with penoscrotal elephantiasis.

Lymphogranuloma venereum (LGV) is a sexually transmitted disease of the lymph channels caused by Chlamydia trachomatis. Esthiomene, a rare late manifestation of LGV, is a primary infection affecting the lymphatics of scrotum, penis, or vulva. The male genitalia are affected less commonly by esthiomene, but we report a male patient who presented with inguinal syndrome, penoscrotal elephantiasis, along with enlargement of femoral lymph nodes.

Adult↗

Preparation and comparative evaluation of 99mTc-labeled 2-iminothiolane modified antibodies and CITC-DTPA immunoconjugates of anti-EGF-receptor antibodies.

The use of antibodies as targeting agents for the delivery of radioisotopes to tumors is a promising concept that has received widespread attention since the advent of monoclonal antibody (mAb) technology. The following studies are described in this article: the 99mTc-randiolabeling of 2-iminothiolane (2-IT) modified antibodies and 6-p-isothiocyanatobenzyl- diethylene-triamine penta-acetic acid (CITC-DTPA) immunoconjugates of anti-EGF-receptor antibodies murine ior egf/r3 and humanized h-R3; the analytical methods for quality control of the radiopharmaceutical such as instant thin layer chromatography-silica gel (ITLC-SG); the biological assessment of the radiolabeled molecule using flow cytometry analysis; in vitro stability studies with cysteine and DTPA challenge and the biodistribution studies in 4NMRI xenografted nude mice with U-87 human glioblastoma multiforme and MDA-MB-468 breast cancer cell lines. Labeling efficency of (96.48 +/- 0.70%) (98.42 +/- 0.38%), (94.8 +/- 1.25%) and (96.41 +/- 0.89%) was achieved for 99mTC-2-IT ior efg/r3, 99mTc-CITC-DTPA- ior egf/r3, 99mTc-CITC-DTPA- h-R3 and 99mTc-DIACIM h-R3, respectively. Radiocolloids were less than 2.0% in all cases. The biological activity measured by flow cytometry analysis using the MDA-MB-468 breast cancer cell line showed an immunoreactivity fraction greater than 85% in all concentrations of each immunoconjugate. Challenge studies demonstrated no evidence of transcomplexation of 99mTc to 1.0 mM DTPA for 2-IT modified antibody ior egf/r3 and CITC-DTPA immunoconjugates and only 8.7%, 4.9% and 5.0% of the 99mTc-radiolabeled was transcomplexed to 1.0 mM cysteine after 1 h incubation at 37 degrees C for 2-IT modified antibody ior egf/r3, CITC-DTPA ior egf/r3 and CITC-DTPA h-R3, respectively. Biodistribution studies with 2-IT modified antibodies and CITC-DTPA immunoconjugates indicated high tumor uptake in both cell lines with both immunoconjugates and no accumulation of the radiolabeled antibodies in normal organs.

Adenocarcinoma↗

Choroid plexus papillomas of the cerebellopontine angle.

The cerebellopontine angle (CPA) is a rare site for the growth of choroid plexus papilloma (CPP). The clinicoradiological diagnosis of this tumor in the CPA is difficult because of the nonspecific clinical presentation and radiological features. Five cases of choriod plexus papilloma (3 males, 2 females) operated upon at this center are reviewed. All the cases were operated upon by retromastoid suboccipital craniectomy. As they all presented with a typical CPA syndrome without any distinctive radiological feature, a clinicoradiological diagnosis of CPP could not be reached in any of these. The diagnosis of CPP could only be suspected at the operation table and established on histopathological examination. Two patients developed recurrences at the primary site following surgery. One patient developed recurrence twice despite gross total excision of tumor in each sitting. Subsequently, this patient remained symptom free for a follow-up period of 1 year. Another patient developed recurrence 2 years following surgery, but he died due to septicemia and aspiration pneumonitis. Therefore definitive surgery could not be performed. Radiotherapy was offered to one of the patients having residual mass post operatively, to render her symptom free for a 4 year follow-up. The remaining two patients have also showed progressive improvement in their symptoms following surgery for 4 years on follow-up. Hydrocephalus was a common feature in all the cases preoperatively, but only one required shunt CSF diversion, because of rapid deterioration in visual equity. In all other cases, hydrocephalus was managed conservatively. Surgery remains the main modality of treatment for CPP, both for primary and recurrent tumors, but radiotherapy may have a role in cases of recurrence, which are quite frequent.

Adult↗

Management of congenital atlanto-axial dislocation: some lessons learnt.

Congenital atlantoaxial dislocation (AAD) has a high incidence in India. In these patients, even a minor trauma may precipitate severe morbidity. The management of mobile AAD consists of posterior stabilization. In fixed AAD, the offending compressive element is present anterior to the cervicomedullary junction, which should be generously removed by the transoral approach. In many of these patients, the assimilated posterior arch of atlas or the incurving posterior margin of the foramen magnum or associated Chiari I malformation also adds to the compromise of the canal diameter at the foramen magnum. Thus, in cases of fixed AAD, the hour glass appearance of the spinal canal at the craniovertebral junction should be converted into a funnel shaped appearance which is close to normal. Since these procedures require a generous removal of the osteoligamentous structures, posterior fusion should be done in all cases after decompressive surgery. In this review, the observations that emerged during the management of congenital AAD are presented with a special focus on the assessment scales modified to the Indian settings, hypermobile AAD, rotary C1-2 dislocation, and AAD associated with Chiari I malformation and syringomyelia.

Anesthesia↗