Biomedical subjects

S Rajasekaran

Publications and source records attributed to S Rajasekaran.

At least 19 recordsLinked to original sources

PubMed2007

Randomized clinical study to compare the accuracy of navigated and non-navigated thoracic pedicle screws in deformity correction surgeries.

STUDY DESIGN: Randomized clinical trial (level I evidence). OBJECTIVE: To compare the accuracy of non-navigation and Iso-C based navigation in pedicle screw fixation in thoracic spine deformities. SUMMARY OF BACKGROUND DATA: Thoracic pedicle screw insertion for spinal deformity correction can be associated with increased pedicle breaches. Iso-C based navigation has been reported to improve the accuracy of pedicle screw placement, but its use in the presence of deformity has not been reported. METHODS: Twenty-seven patients with scoliosis and 6 patients with kyphosis had a total of 478 thoracic pedicle screws. The average Cobb angle was 58.4 degrees +/- 8 degrees (range 50 degrees -80 degrees), and the mean kyphotic angle was 54.6 degrees +/- 4 degrees (range 51 degrees -76 degrees). By random allocation, 17 patients had screw insertion under navigation (242 screws) and 16 under fluoroscopic control (236 screws). The 2 groups were compared for accuracy of screw placement, time for screw insertion, and the number of times the C-arm had to be brought into the field. Two independent blinded observers determined accuracy using postoperative computed tomography assessments. RESULTS: There were 54 (23%) pedicle breaches in the non-navigation group as compared to only 5 (2%) in the navigation group (P < 0.001). Thirty-eight screws (16%) in the non-navigation group had penetrated the anterior or lateral cortex compared to 2 screws (0.8%) in the navigation group. Average screw insertion time in the non-navigation group was 4.61 +/- 1.05 minutes (range 1.8-6.5) compared to 2.37 +/- 0.72 minutes (range 1.16-4.5) in navigation group (P < 0.01). The C-arm had to be moved into the operation field on an average of 1.5 +/- 0.25 times (range 1-3) per screw. With single screening data, an average of 11.4 pedicles (range 9-14) could be visualized without necessity to bring the C-arm into operating field again. CONCLUSIONS: Iso-C navigation increases accuracy, and reduces surgical time and radiation in thoracic deformity correction surgeries.

Adolescent↗

PubMed2006

A philosophy of care of open injuries based on the Ganga hospital score.

In the management of Type IIIb injuries, Gustilo's classification has the disadvantages of a poor intra and inter-observer agreement rate, low specificity and sensitivity to salvage and inability to predict functional outcomes. We propose here a validated score which assesses the severity of injury to the covering structures, skeletal structures and functional tissues of the injured limb separately along with providing weightage to the presence of co-morbid factors. A high sensitivity and specificity for amputation was documented when a score of 14 was used as the threshold score. In salvaged limbs, the score was found to offer guidelines in protocols for reconstruction. According to the total score, injuries were treated by 'Fix and close' protocol; 'Fix, Bone Graft and Close' protocol, 'Fix and Flap' protocol or 'Stabilise, Watch, Assess and Reconstruct' protocol. The score was thus found to be useful clinically not only to assess salvage but also to provide guidelines in reconstruction.

Amputation, Surgical↗

PubMed2006

Immune reconstitution syndrome in a child with TB and HIV.

Immune reconstitution syndrome (IRS) is the transient worsening or appearance of new signs, symptoms or radiological manifestation of an opportunistic infection occurring after the initiation of Highly active antiretroviral therapy (HAART) and is not due to treatment failure or new infection. We describe a case of a HIV infected child with tubercular (mediastinal) lymphadenitis with worsening of clinical and radiological features on starting HAART.

Anti-HIV Agents↗

PubMed2006

Plant-based formulation in the management of chronic obstructive pulmonary disease: a randomized double-blind study.

BACKGROUND: A randomized double-blind placebo controlled clinical study was undertaken to investigate the safety and efficacy of a plant-based formulation (DCBT1234-Lung KR), which earlier through 2 trials was found to improve FEV1 and the quality of life of COPD patients. OBJECTIVE: The efficacy of DCBT1234-Lung KR was assessed using pulmonary function tests, arterial blood gas (ABG) analyses and the clinical symptoms of COPD in a 6-month study period against a matching placebo and a biomedical drug combination (salbutamol+theophylline+bromhexine). METHODS: One hundred and five subjects aged between 35 and 85 years with a smoking history of more than 20 pack years, showing little or no improvement in FEV1 upon a bronchial challenge of 200 microg of inhaled salbutamol and exhibiting ABG percentage of less than 85% of oxygen saturation were taken up for the study. The study had 3 arms viz., the plant-based formulation (DCBT1234-Lung KR), placebo and salbutamol (12 mg/day) plus theophylline (300 mg/day) plus bromhexine (24 mg/day). The end point of the study was determined as an improvement of FEV1 by 200 mL and/or increased ABG values (>90% PaO2) and clinical symptoms like dyspnoea, wheezing, cough, expectoration, disability, and sleep disturbances. RESULTS: DCBT1234-Lung KR patients showed statistically significant (95% level) improvement in FEV1 and PaO2 in comparison with salbutamol+theophylline+bromhexine and placebo patients. Twenty-three per cent of DCBT1234-Lung KR patients, 19% of salbutamol+theophylline+bromhexine group and 12% of placebo group patients showed the desired 200 mL improvement in FEV1 values in comparison with the other 2 arms. Improved PaO2 was observed in 15.4% of the DCBT1234-Lung KR patients while no improvement was seen with patients in any other arms. Symptoms like dyspnoea, wheezing, cough, expectoration, disability and sleep disturbances also significantly reduced in DCBT1234-Lung KR and the biomedical group patients, but not in the placebo arm. CONCLUSIONS: DCBT1234-Lung KR was equivalent, if not better than the present day treatment with salbutamol, theophylline and bromhexine combination in COPD patients and this was ascertained using FEV1 and ABG values.

Adult↗

PubMed2006

Intradural spinal tuberculosis in the absence of vertebral or meningeal tuberculosis: a case report.

We present a patient with spinal intradural tuberculosis in the absence of both vertebral and meningeal tuberculosis. Diagnosis was made based on intra-operative findings and was confirmed by histopathology. Early surgical decompression along with a combination of steroid and antitubercular therapy resulted in a good outcome. At 26-month follow-up, the patient regained bladder control and was able to walk with support. Clinical features, magnetic resonance imaging, and intra-operative findings are described. Pathology and the relevant literature are discussed.

Adult↗

PubMed2006

Variant of a lumbar disc cyst in a 13-year-old girl: a case report.

A disc cyst is a rare entity with a clinical presentation that closely mimics an intervertebral disc herniation. Disc cysts are ventrally located, intraspinal, extradural cystic lesions that communicate with the parent intervertebral disc through a ruptured annulus. We present the clinical features, magnetic resonance imaging, intra-operative and histopathological findings of a variant of a lumbar intervertebral disc cyst in a 13-year-old girl who presented with a 6-month history of unilateral radiculopathy following an injury. Magnetic resonance imaging revealed a large posterocentral, fluid-filled cyst occupying the L5-S1 interspace and bulging into the spinal canal. The cyst was confined within an intact bulging annulus fibrosis and extended directly from the parent disc. The cyst was surgically decompressed, resulting in complete symptomatic relief.

Adolescent↗

PubMed2006

A score for predicting salvage and outcome in Gustilo type-IIIA and type-IIIB open tibial fractures.

Limb-injury severity scores are designed to assess orthopaedic and vascular injuries. In Gustilo type-IIIA and type-IIIB injuries they have poor sensitivity and specificity to predict salvage or outcome. We have designed a trauma score to grade the severity of injury to the covering tissues, the bones and the functional tissues, grading the three components from one to five. Seven comorbid conditions known to influence the management and prognosis have been given a score of two each. The score was validated in 109 consecutive open injuries of the tibia, 42 type-IIIA and 67 type-IIIB. The total score was used to assess the possibilities of salvage and the outcome was measured by dividing the injuries into four groups according to their scores as follows: group I scored less than 5, group II 6 to 10, group III 11 to 15 and group IV 16 or more. A score of 14 to indicate amputation had the highest sensitivity and specificity. Our trauma score compared favourably with the Mangled Extremity Severity score in sensitivity (98% and 99%), specificity (100% and 17%), positive predictive value (100% and 97.5%) and negative predictive value (70% and 50%), respectively. A receiver-operating characteristic curve constructed for 67 type-IIIB injuries to assess the efficiency of the scores to predict salvage, showed that the area under the curve for this score was better (0.988 (+/- 0.013 SEM)) than the Mangled Extremity Severity score (0.938 (+/- 0.039 SEM)). All limbs in group IV and one in group III underwent amputation. Of the salvaged limbs, there was a significant difference in the three groups for the requirement of a flap for wound cover, the time to union, the number of surgical procedures required, the total days as an in-patient and the incidence of deep infection (p < 0.001 for all). The individual scores for covering and functional tissues were also found to offer specific guidelines in the management of these complex injuries. The scoring system was found to be simple in application and reliable in prognosis for both limb-salvage and outcome measures in type-IIIA and type-IIIB open injuries of the tibia.

Adolescent↗

PubMed2006

Spontaneous rapid osteolysis in Paget's disease after internal fixation of subtrochanteric femoral fracture.

Rapidly-progressive spontaneous progression of the osteolysis following internal fixation of pathological fracture in patients with Paget's disease has not been previously reported. We describe two patients, aged 59 and 65 years, respectively, who had pathological subtrochanteric fractures in Pagetic femora fixed internally using an interlocked intramedullary nail, and who developed spontaneous rapid osteolysis. Both patients responded favourably to long-term treatment with alendronate, with resultant fracture union and resolution of osteolysis.

Aged↗

PubMed2005

Spontaneous complete recovery of paraplegia caused by epidural hematoma complicating epidural anesthesia: a case report and review of literature.

STUDY DESIGN: Case report. SETTING: Tertiary referral spinal surgery center in South India. OBJECTIVES: To report a patient who developed epidural hematoma following epidural anesthesia causing acute paraplegia. Surgery was avoided due to concomitant gastrointestinal bleeding and poor general condition. Patient showed early signs of recovery with complete resolution of neurological deficits in 12 weeks. CONCLUSION: Surgery can be avoided in patients who show early signs of neurological recovery following epidural hematoma.

Aged↗

PubMed2005

Plant-based formulation for bronchial asthma: a controlled clinical trial to compare its efficacy with oral salbutamol and theophylline.

BACKGROUND: Plant-based medicine is the 3rd most popular choice of both adults (11%) and children (6%) suffering from Asthma. While several plant-based formulations have been reported for the treatment of asthma in the past, many authors have published their reservations on clinical trials carried out using complementary and alternative medicines. OBJECTIVES: The authors desired to eliminate the shortcomings of the earlier clinical trials carried out by many investigators in a structured study. Therefore, a 12-week randomized double-blind placebo-controlled clinical study was conducted to investigate the efficacy of a plant-based formulation (DCBT4567-Astha-15) in comparison with oral salbutamol, salbutamol + theophylline and a matching placebo in patients with reversible asthma. METHODS: Ninety-four patients between 15 and 50 years of age, showing 15% improvement in forced expiratory volume in 1 s (FEV(1)) 15 min after a bronchial challenge of inhaled salbutamol (200 microg) were recruited, and the end point of the study was determined as a 15% improvement in FEV(1) and clinical symptoms like dyspnoea, wheezing, cough, expectoration, disability, sleep disturbances and respiration rate. RESULTS: DCBT4567-Astha-15, salbutamol and salbutamol + theophylline patients showed statistically significant improvement in FEV(1), while placebo patients did not show any improvement. Fifty percent of DCBT4567-Astha-15, 48% of salbutamol, 58% of salbutamol + theophylline and 26% of placebo patients showed the desired 15% improvement in FEV(1). Improved mean FEV(1) values at the end of the trial indicated that the salbutamol - theophylline combination was superior followed by salbutamol and DCBT4567-Astha-15. Clinical symptoms like dyspnoea, wheezing, cough, expectoration, disability, and sleep disturbances were significantly reduced in DCBT4567-Astha-15 patients compared to patients of the other three arms. CONCLUSIONS: DCBT4567-Astha-15 was as efficacious as salbutamol (12 mg/day) or salbutamol (12 mg/day) in combination with theophylline (200 mg/day) in the treatment of reversible asthmatics. Quality of life of patients also improved with DCBT4567-Astha-15 drug treatment.

Administration, Oral↗

PubMed2005

Exact algorithms for planted motif problems.

The problem of identifying meaningful patterns (i.e., motifs) from biological data has been studied extensively due to its paramount importance. Three versions of this problem have been identified in the literature. One of these three problems is the planted (l, d)-motif problem. Several instances of this problem have been posed as a challenge. Numerous algorithms have been proposed in the literature that address this challenge. Many of these algorithms fall under the category of heuristic algorithms. In this paper we present algorithms for the planted (l, d)-motif problem that always find the correct answer(s). Our algorithms are very simple and are based on some ideas that are fundamentally different from the ones employed in the literature. We believe that the techniques we introduce in this paper will find independent applications.

Algorithms↗

PubMed2005

Modulatory effects of Aloe vera leaf gel extract on oxidative stress in rats treated with streptozotocin.

Oxidative stress is currently suggested as a mechanism underlying diabetes and diabetic-related complications. Oxidative stress results from an imbalance between radical-generating and radical-scavenging systems. Many secondary plant metabolites have been reported to possess antioxidant activity. This study was designed to evaluate the potential antioxidative activity of the ethanolic extract from Aloe vera leaf gel in the plasma and pancreas of streptozotocin (STZ)-induced diabetic rats. Glibenclamide was used as a standard reference drug. Oral administration of ethanolic extract at a concentration of 300 mg kg(-1) body weight for 21 days resulted in a significant reduction in fasting blood glucose, thiobarbituric acid reactive substances, hydroperoxides and alpha-tocopherol and significant improvement in ascorbic acid, reduced glutathione and insulin in the plasma of diabetic rats. Similarly, the treatment also resulted in a significant reduction in thiobarbituric acid reactive substances, hydroperoxides, superoxide dismutase, catalase and glutathione peroxidase and significant improvement in reduced glutathione in the pancreas of STZ-induced diabetic rats when compared with untreated diabetic rats. The ethanolic extract appeared to be more effective than glibenclamide in controlling oxidative stress. Thus, this study confirms the ethnopharmacological use of Aloe vera in ameliorating the oxidative stress found in diabetes.

Alkaloids↗

PubMed2005

Mineral contents of aloe vera leaf gel and their role on streptozotocin-induced diabetic rats.

The role of some inorganic elements like vanadium, zinc, sodium, potassium, calcium, copper, manganese, and traces of chromium in the improvement of impaired glucose tolerance and their indirect role in the management of diabetes mellitus are being increasingly recognized. In traditional methods, medicinal plants are being used, which contain both organic and inorganic constituents. In the present study, an attempt has been made to analyze the inorganic elements present in Aloe vera leaf gel and their role on diabetes-related biochemical alterations in experimental rats. Special emphasis was given to the inorganic parts by carefully preparing ash of the leaf gel. The results clearly indicate the presence of several hypoglycemic-activity-possessing elements in the gel. The ash treatment also resulted in hypoglycemic action. In conclusion, the presence of various inorganic trace elements in the gel might account for the hypoglycemic nature of the plant.

Aloe↗

PubMed2005

Translaminar facetal screw (Magerl's) fixation.

Translaminar facet screw fixation (TLFS) achieves stabilization of the vertebral motion segment by screws inserted at the base of the spinous process, through the opposite lamina, traversing the facet joint, and ending in the base of the transverse process. It is simple, does not require any specialized equipment, and has the advantages of being a procedure of lesser magnitude, lesser operative time, less cost and few complication rate. Recently there is growing interest in this technique to augment the anterior lumbar fusions to achieve global fusion less invasively. In this review article, we discuss the clinical and biomechanical considerations, surgical technique, indications, contraindications and recent developments of TLFS fixation in lumbar spine fusion.

Biomechanical Phenomena↗

PubMed2005

Anti-tuberculosis drug resistance in patients with HIV and tuberculosis in South India.

SETTING: Tuberculosis Research Centre clinics at Chennai and Madurai, Tamil Nadu, South India. OBJECTIVES: To investigate the prevalence and pattern of drug resistance among patients with HIV and pulmonary tuberculosis (PTB). DESIGN: Prospective cohort study of HIV-positive patients with PTB between January 2001 and May 2003. Sputum mycobacterial culture and drug susceptibility testing were performed. RESULTS: A total of 204 patients with positive sputum cultures for Mycobacterium tuberculosis were included; 167 of them were new cases, and 37 had a history of previous anti-tuberculosis treatment for > 1 month. Among the former, resistance to isoniazid (INH) was observed in 22 (13%) and MDR-TB in 7 (4.2%). Reported resistance rates in this geographic area among new cases ranged from 15% to 28% for INH and 2.8% to 3.4% for MDR (INH + rifampicin [RMP]). In contrast, among HIV-positive patients with a history of previous treatment, resistance was found to INH in 10 (27%) and to RMP in 7 (18.9%), while MDR-TB was seen in 5 (13.5%) patients. CONCLUSION: Among new TB patients, MDR-TB is marginally higher in HIV-positive patients than in the non-HIV-infected population in this region. Standard treatment guidelines should be followed. Higher rates of drug resistance are observed among previously treated patients.

Antitubercular Agents↗

PubMed2005

Colonization of mycoplasma in the upper respiratory tract of AIDS patients with pulmonary symptoms in Chennai, India.

BACKGROUND & OBJECTIVE: Mycoplasmas have been implicated in causing minor to severe respiratory infections in man. Mycoplasmas are considered to act as cofactors in patients with AIDS. A preliminary study was conducted to isolate mycoplasmas from sputum specimens of AIDS patients and non-HIV patients with underlying pulmonary symptoms and signs. METHODS: A total of 130 sputum samples (100 from AIDS patients and 30 from non-HIV) were cultured on standard pleuropneumonia-like organisms (PPLO) glucose agar up to 3 wk. The plates were examined for the presence of fried-egg colonies characteristic of Mycoplasma. Subsequently the plates were stained using Diene's stain. Sputum specimens from the AIDS patients were also screened for other bacterial pathogens. RESULTS: Mycoplasmas were detected from 36 (36%) of the AIDS patients and only 5 (16.6%) of the non HIV control individuals with underlying pulmonary symptoms. Data on the detection rates of other microorganisms from the AIDS cases were also analysed. INTERPRETATION & CONCLUSION: This preliminary study provided supportive evidence that mycoplasma colonized in upper respiratory tract of individuals with AIDS to a larger extent than that of the non HIV subjects with pulmonary symptoms. Further studies need to be done to characterize mycoplasma isolates to species level.

AIDS-Related Opportunistic Infections↗

PubMed2004

ISSLS prize winner: A study of diffusion in human lumbar discs: a serial magnetic resonance imaging study documenting the influence of the endplate on diffusion in normal and degenerate discs.

STUDY DESIGN: An in vivo serial magnetic resonance imaging study of diffusion characteristics in human lumbar discs over 24 hours in healthy volunteers and patients with low back pain. OBJECTIVES: To document the temporal pattern of diffusion in normal human lumbar discs and to study the influence of the vascularity of bone and the status of endplate on diffusion in the normal and degenerate discs. SUMMARY OF BACKGROUND DATA: Diffusion is the only source of nutrition to the discs, but no firm data are available on pattern of diffusion in humans. More data on this important subject are required to improve our understanding of disc degeneration and to probe research possibilities for preventing the same. METHODS: The diffusion pattern over 24 hours following gadodiamide injection was studied in 150 discs (96 normal and 54 degenerate). Signal intensity values for three regions of interest in bone (i.e., vertebral body, subchondral bone, and endplate zone) and seven in the disc were calculated, and normal percentiles of diffusion were derived for these regions. Enhancement percentage for each time period, peak enhancement percentage for each region, and the time taken to achieve peak enhancement percentage (Tmax) were used to define and compare diffusion characteristics and plot a time-intensity curve to document the 24-hour temporal pattern. The correlation of blood flow of the bone as measured by peak enhancement percentage of vertebral body, the status of the endplate zone as measured by the peak enhancement percentage, and Tmax of the endplate zone were correlated with the diffusion of the disc.Univariate analysis of variance, multiple comparisons, appropriate tests for significance, and stepwise linear regression analysis were used for analysis of the data using SPSS software. RESULTS: In normal discs, a "diffusion march" from the vertebral body to the center of disc was noted with the SImax being observed at 5 min in the vertebral body and subchondral bone, at 2 hours in the endplate zone, and at 6 hours in the nucleus pulposus. A significant difference in mean peak enhancement percentage was observed between that of the body and the discs in those less than 10 years and those above the age of 20 years (P < 0.001). Alterations in endplate zone produced distinct magnetic resonance imaging signs of disturbance in diffusion, which offered a reliable noninvasive method of identifying endplate cartilage damage. Stepwise linear regression analysis showed that the significant variable influencing diffusion to the center of the nucleus pulposus of the total sample was peak enhancement percentage of endplate zone (R2 = 0.216; P < 0.001), that of degenerate discs was peak enhancement percentage of endplate zone (R2 = 0.322; P < 0.001), and that of normal discs (R2 = 0.324; P < 0.001) was age. CONCLUSIONS: Serial postcontrast magnetic resonance imaging studies offer a reliable method of assessing the diffusion of the discs and the functional status of the endplate cartilage. Endplate cartilage damage increases with age and produces considerable changes in diffusion. The present study has described reliable signs by which these damages can be identified in vivo. Aging and degeneration have been shown to be two separate processes by documenting clear-cut differences in diffusion. The present data encourage use of diffusion studies as a noninvasive method to assess the physiologic status of the disc and endplate and to study the effect of drugs, smoking, mechanical loading, exercises, etc. on the physiology of the disc.

Adolescent↗

PubMed2004

Hypoglycemic effect of Aloe vera gel on streptozotocin-induced diabetes in experimental rats.

In the present study an attempt has been made to evaluate the presence of hypoglycemic activity in the alcoholic extract of Aloe vera gel. Effects of oral administration of A. vera extract at a concentration of 200 and 300 mg/kg of body weight on (a) normal fasted rats, (b) oral glucose-loaded rats, and (c) streptozotocin-induced diabetic rats have been studied. A. vera extract maintain the glucose homeostasis by controlling the carbohydrate metabolizing enzymes.

Administration, Oral↗