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J Arora

Publications and source records attributed to J Arora.

14 recordsLinked to original sources
PubMed2005

External fixation in comminuted, displaced intra-articular fractures of the distal radius: is it sufficient?

INTRODUCTION: External fixation has been extensively used to treat the intra-articular fractures of the distal radius and it has several distinct advantages over conventional POP cast and plate fixation. However, the limitation of external fixation to achieve articular congruity in the comminuted intra-articular fractures of the distal radius has been documented in the literature. This could be because external fixation alone does not expand crushed cancellous bone and cannot work without soft tissue hinges. This prospective study was conducted to look at the results of comminuted, displaced intra-articular fractures of the distal radius treated exclusively by external fixation. MATERIALS AND METHODS: A 2-year follow-up of 27 patients with comminuted, displaced intra-articular fractures of distal radius that were treated exclusively by external fixation is presented. The radiological results, functional results and complications were analyzed according to the scoring system given by Jakim et al. RESULTS: Anatomical reduction could not be achieved in 12 patients (44%) and reduction was lost in two patients (7%). Excellent and good results were seen in 59.3%, fair results were seen in 22.2% and poor results were seen in 18.5% of the cases. Outcome scores of patients without articular step were significantly better as compared to the patients with articular step at healing. There was a positive correlation between the restoration of normal anatomy (radiological results) and the functional outcome (r=0.775). Overall nine patients (33%) had complications. CONCLUSION: We conclude that although the external fixation is reliable in maintaining the reduction in displaced comminuted intra-articular fractures, it is inadequate in restoring articular congruity in many cases. The complications of external fixation are frequent and may be potentially serious in nature.

Adolescent↗
PubMed2005

Osteolysis in a surface-cemented, primary, modular Freeman-Samuelson total knee replacement.

We analysed at a mean follow-up of 7.25 years the clinical and radiological outcome of 117 patients (125 knees) who had undergone a primary, cemented, modular Freeman-Samuelson total knee replacement. While the tibial and femoral components were cemented, the patellar component was uncemented. A surface-cementing technique was used to secure the tibial components. A total of 82 knees was available for radiological assessment. Radiolucent lines were seen in 41 knees (50%) and osteolytic lesions were seen in 13 knees (16%). Asymptomatic, rotational loosening of the patellar implant was seen in four patients and osteolysis was more common in patients with a patellar resurfacing. Functional outcome scores were available for 41 patients (41 knees, 35%) and the mean Western Ontario McMasters Universities score was 77.5 (sd 19.5) and the cumulative survival was 93.4% at ten years with revision for aseptic loosening as an endpoint. Increased polyethylene wear from modular components, a rotationally-loose patella, and the surface-cementing technique may have contributed to the high rate of osteolysis seen in our study.

Aged↗
PubMed2004

The role of pre-operative templating in primary total knee replacement.

Templating of preoperative X-rays is routinely performed before a total knee replacement. We performed this retrospective study on preoperative templating in primary total knee replacement to assess its accuracy and reproducibility. Preoperative radiographs of 47 patients were templated twice by two observers separately after a gap of 3 months. The size of actual implant used was compared to the size predicted by templating. Data were analysed to assess inter and intra-observer variation. Templating was accurate for both tibial and femoral components in only 53.2% of observations. This study also revealed that templating is a highly-subjective and observer-dependent technique. Inter-observer and intra-observer mismatch was present in 46.8% and 43.6% of readings respectively. We conclude from this study that preoperative templating is neither accurate nor reproducible.

Arthroplasty, Replacement, Knee↗
PubMed2003

Recurrent osteoid osteoma of the lunate: a case report and review of the literature.

Osteoid osteoma is a benign tumour of bone that rarely localises in the carpal bones. Its treatment by curettage and bone grafting is considered to be curative and its recurrence is thought to be rare. We report a case of an osteoid osteoma of the lunate, which recurred seven years after the initial operation. Recurrent osteoid osteoma of the lunate bone has not been reported in the literature. We present this case report for its atypical presentation and diagnostic difficulty and also to alert the readers of the possibility of an osteoid osteoma as a cause of the chronic unexplained wrist pain in young adults.

Adult↗
PubMed1998

Evaluation of various diagnostic signs on percutaneous transhepatic cholangiography in obstructive jaundice.

Twenty patients of obstructive jaundice were subjected to percutaneous transhepatic cholangiography (PTC) of which 17 were operated on. Patients were divided in 4 groups according to the site of obstruction. The diagnostic signs observed were: Complete block with interface having convexity downwards (4), convexity upwards (3), biconcave caudal cut off (6), smooth edged cut off (one), irregular edged cut off (one) and non-specific appearance (one); incomplete block with interface having convexity upwards (one); biconcave caudal cut off (2) and multiple smooth central filling defects (2). In one case there was incomplete obstruction at two sites giving rise to two different signs. PTC was 100% correct in accurately telling the site of lesion. As regards the nature of the lesion the diagnosis on PTC was found correct in 15 out of 17 cases (88.5%).

Cholangiography↗
PubMed1998

Mechanical stretch alters the actin cytoskeletal network and signal transduction in human trabecular meshwork cells.

PURPOSE: Human trabecular meshwork (HTM) cells were mechanically stretched in vitro as a potential model for the distension of this tissue that can occur in vivo in response to increased pressure gradients. Cell morphology and certain components of the signal transduction pathways, including the mitogen-activated protein kinase (MAPK) and c-Jun N-terminal protein kinase (JNK) pathways, were evaluated for stretch-induced alterations. METHODS: Primary HTM cells grown in tissue culture were subjected to a mechanical stretch lasting from 10 seconds to 4 days. The actin cytoskeletal network was visualized by phalloidin staining. Proteins phosphorylated on their tyrosine residues were isolated using an immunoaffinity system and were analyzed by gel electrophoresis and immunostaining. Mitogen-activated protein kinase activity was evaluated using an in-gel assay system, and the mRNA levels of c-fos and c-jun were determined by quantitation of competitive reverse transcription-polymerase chain reaction. In addition, the amount of c-Fos protein was estimated by chemiluminescent immunoblot analysis. RESULTS: On stretching, the HTM cells elongated but regained their normal morphologic characteristics within 24 hours. Unstretched HTM cells displayed a diffuse F-actin microfilament network, whereas stretched cells exhibited complex geodesic patterns. Ten seconds after stretching began, the level of tyrosine phosphorylation on the six major phosphoproteins significantly decreased between 80% and 100%, whereas the level of paxillin tyrosine phosphorylation significantly increased 39%. Stretching caused MAPK activity and the amount of mRNA and protein of the immediate-early gene c-fos to decrease more than 60% within 2 minutes, but within 15 to 30 minutes they increased above or equivalent to normal levels. The level of c-jun mRNA was unchanged by stretching. CONCLUSIONS: In response to a mechanical stretch, major cytoskeletal alterations occur in HTM cells, which involve changes in the levels of tyrosine phosphorylation. Mechanotransduction (signal transduction by mechanical stimulation) through the MAPK signaling pathway was significantly depressed immediately after stretching; however, the JNK pathway appeared to be unaffected. The data suggest that HTM cells adapt to mechanical stress by altering the cytoskeletal network and signaling cascades.

Actin Cytoskeleton↗
PubMed1997

Transient loss of alphaB-crystallin: an early cellular response to mechanical stretch.

Human trabecular meshwork (HTM) is distended and stretched with increases in intraocular pressure. During this stretching, there is a rearrangement of actin filaments. The HTM cells express alpha B-crystallin, a small heat shock protein that may have a role in the stabilization and regulation of the cytoskeleton in mammalian cells. The levels of alpha B-crystallin were examined in trabecular meshwork cells after mechanical stretch. Human TM primary cell cultures, plated onto silicone sheets, were subjected to a single 10% linear stretch and samples were prepared at various times after stretch for immunoblotting or Northern blotting. Immunoblots of total protein extracts with antibody specific for alpha B-crystallin detected a 26% decrease of cellular alpha B-crystallin levels within 2 minutes. After 1 hour alpha B-crystallin levels had decreased 90% compared to control cells. The levels of alpha B-crystallin began to recover in cells stretched for 2 hours and returned to initial levels by 24 hours. Northern blots probed with alpha B-crystallin exon III cDNA detected a transcript of 0.65 kb in human TM cells and the levels of the alpha B mRNA remained constant during alpha B-crystallin protein decrease. Later, levels of the 0.65 kb transcript of alpha B-crystallin increased during the cellular recovery. These results suggest that decreased levels of alpha B-crystallin after mechanical stretch were probably not due to transcriptional changes but rather to increased degradation of alpha B-crystallin protein. An increase in mRNA levels may play a role in the recovery of alpha B-crystallin during reorganization of the cytoskeleton and attachment to the substratum. These data raise the possibility of a specific proteolysis of alpha B-crystallin protein in cells after a physiological challenge.

Blotting, Northern↗
PubMed1976

Hemodynamic changes associated with angina pectoris induced by maximal treadmill exercise: effect of sublingual isosorbide dinitrate on systolic time intervals.

A technique for the study of patients with angina pectoris has been described, in which systolic time interval (STI) measurements are obtained at intervals after the onset of stress-induced angina. The technique is uniquely suited to the evaluation of anti-anginal drugs. Sublingual isosorbide dinitrate (SISD) was randomly alternated with a placebo (P) tablet in a double-blind study of 20 patients with stable angina pectoris. After SISD, compared to placebo, a highly significant shortening of Q-S2 and LVET occurred (p less than 0.001) which lasted throughout the entire 120 minute study period. The hemodynamic basis for these differences was felt to be improved myocardial contractility secondary to a reduction in systemic vascular resistance and reduced venous return induced by the SISD. A significant prolongation of PEP occurred at 60 minutes post-SISD (p less than 0.01). This was attributed to an increase in the gradient between LVEDP and aortic diastolic pressure resulting from reduced venous return after SISD. The PEP/LVET ratio was significantly increased up to 60 minutes after SISD (P less than 0.05). Heart rate was uniformly higher post-SISD, compared to post-placebo values; the differences were highly significant up to 60 minutes (P less than 0.001) and remained significant at 120 minutes (p less than 0.05). The time to angina was significantly longer (immediately post SISD, p less than 0.05; 30 min, p less than 0.001; 60 mins, p less than 0.05; 120 mins, p less than 0.05); and the work load greater, for 120 minutes following SISD: the increase in the latter was highly significant for 30 minutes after SISD (p less than 0.001) and remained significant up to 120 minutes (60 mins, p less than 0.05; 120 mins, p less than 0.05). These observations were attributed to an improvement in myocardial function due to the sublingual isosorbide dinitrate. A high degree of correlation was found to exist between heart rate and the STI. This correlation was negative for the QS2 interval (-0.996) and LVET (-0.993) and positive for PEP (+0.817) and the PEP/LVET ratio (+0.950).

Aged↗
PubMed1976

The effect of respiratory motion on the echocardiogram.

The effects of respiratory movements on the ultrasonic echoes of the cardiac structures were recorded and analyzed in 50 consecutive patients. Deep inspiration in cooperative patients resulted in a considerable increase of dense anterior echoes, with blotting out of any distal or posterior echoes in 12 of 44 patients (group A). In the second or larger series (32 of 44 patients; group B), a posterior displacement of most of the identifiable intrinsic cardiac echoes was seen with deep inspiration, particularly those of the posterior wall of the left ventricle. Forced expiration produced an opposite or anterior displacement of the cardiac echoes. Normal respirations showed similar but smaller excursions.

Echocardiography↗
PubMedDate not supplied

Translocation of adenine nucleotides in the mitochondria of male sterile and male fertile sorghum.

The translocation of ATP from the inside to the outside of the mitochondrial membrane has been studied in a male sterile (2219 A) and a male fertile (2219 B) line of sorghum. The translocation of ATP was found to be substantially lower in case of mitochondria from the male sterile line. The affinity of adenine nucleotides to the translocator proteins of the mitochondrial membrane was found to be almost one half in case of 2219 A as compared to 2219 B when the Km for ATP-ADP was determined by two different assays. It is proposed that the inadequate supply of ATP in the cytosol resulting from its inefficient translocation may contribute to the male sterility in this line.

Adenine Nucleotides↗