Characterization of the epitope recognized by a monoclonal antibody highly specific for blood group M antigen

The mouse monoclonal antibody M2A1 of IgG1 class, which is highly specific for blood group M antigen, was obtained and characterized by means of hemagglutination, enzyme-linked immunosorbent assay, immunoblotting, and inhibition assays. The use of modified M glycoprotein preparations for inhibition tests and of variant McN and Henshaw red cell membranes for immunoblotting showed that M2A1 recognized an epitope including the NH2-terminal serine and sialic acid residues of glycophorin A, whereas the fifth glycine residue was not involved. The reactivity of the antibody with M antigen was distinctly dependent on ionic strength and pH; the optimum was at pH 8 to 9. The alpha-amino group of terminal serine residue was not necessary for the reaction with M2A1 antibody, and the results obtained suggested that the positive charge of this group contributed to decreasing antigen-antibody reactions at pH below 8. The reaction of the antibody with blood group N antigen was not detectable in any of the assays used.     

Head-Up Tilt Test in Patients with High Pretest Likelihood of Neurally Mediated Syncope: An Approximation to the "Real Sensitivity" of this Testing

This study was designed to examine the "true sensitivity" of a specific head-up tilt (HUT) testing protocol using clinical findings. The HUT protocol used 45 minutes at 60 degrees for the baseline portion and intermittent boluses of 2, 4, and 6 micrograms of isoproterenol in the second phase. Eighty-eight patients (40 men and 48 women; mean age of 33.8 +/- 16 years) with recurrent syncope and high pretest likelihood of neurally mediated syncope were included. The following were considerated as high pretest likelihood criteria: (1) at least two syncopal episodes; (2) no structural heart disease and normal baseline ECG; (3) age < 65 years; (4) a typical history of neurally mediated syncope, triggering factors plus premonitory signs; and (5) short duration of symptoms and fast recovery without neurological sequelae. Fifty-four patients (61%) had a positive tilt test (34/88 baseline [39%] and 20/50 with isoproterenol [40%]). The shorter time interval between the last syncopal episode and baseline HUT test was the only predictor for a positive response (P < 0.003). Conversely, this time interval was not predictor of positive responses during isoproterenol-tilt testing. In conclusion: (1) we claim a "sensitivity" for this combined protocol of 61%; and (2) our results indicate that patients with syncope of unknown origin must be tilted nearest as possible to the last syncope to increase the positive responses of HUT test.     

Angiotensin‐converting enzyme inhibition increases glucose‐induced insulin secretion in response to acute restraint

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Skull Flexure as a Contributing Factor in the Mechanism of Injury in the Rat when Exposed to a Shock Wave

The manner in which energy from an explosion is transmitted into the brain is currently a highly debated topic within the blast injury community. This study was conducted to investigate the injury biomechanics causing blast-related neurotrauma in the rat. Biomechanical responses of the rat head under shock wave loading were measured using strain gauges on the skull surface and a fiber optic pressure sensor placed within the cortex. MicroCT imaging techniques were applied to quantify skull bone thickness. The strain gauge results indicated that the response of the rat skull is dependent on the intensity of the incident shock wave; greater intensity shock waves cause greater deflections of the skull. The intracranial pressure (ICP) sensors indicated that the peak pressure developed within the brain was greater than the peak side-on external pressure and correlated with surface strain. The bone plates between the lambda, bregma, and midline sutures are probable regions for the greatest flexure to occur. The data provides evidence that skull flexure is a likely candidate for the development of ICP gradients within the rat brain. This dependency of transmitted stress on particular skull dynamics for a given species should be considered by those investigating blast-related neurotrauma using animal models.     

Diabetes mellitus in India: The modern scourge

India has a high prevalence of diabetes mellitus and the numbers are increasing at an alarming rate. In India alone, diabetes is expected to increase from 40.6 million in 2006 to 79.4 million by 2030. Studies have shown that the prevalence of diabetes in urban Indian adults is about 12.1%, the onset of which is about a decade earlier than their western counterparts and the prevalence of Type 2 diabetes is 4–6 times higher in urban than in rural areas. The risk factors peculiar for developing diabetes among Indians include high familial aggregation, central obesity, insulin resistance and life style changes due to urbanization. Screening for gestational diabetes and impaired glucose tolerance among pregnant women provides a scope for primary prevention of the disease in mothers as well as in their children. The problems of obesity and impaired glucose tolerance (IGT) (important predisposing factors) are not confined to adults alone but children are also increasingly getting affected. Most long standing macro and micro vascular complications are also more common among Indian diabetics as compared to other races and ethnic groups. A strong familial clustering of diabetic nephropathy among Indian Type 2 diabetics has also been noted. Clustering of cardiovascular risk factor like Syndrome X is common among urban Indians. The rising incidence of diabetes and its complications are going to pose a grave health care burden on our country. Timely effective interventions/measures and screening tests for complications at the time of diagnosis becomes imperative not only for early detection, but also to prevent progression to end stage disease. Screening for gestational diabetes among pregnant women would also go a long way in primary prevention of the disease. Life style changes/interventions and drugs like rosiglitazone are the current strategies that can prevent and/or delay the onset of diabetes. Simple interventional strategies like “Eat less, Eat on time and Walk more” can go a long way in preventing these chronic disorders among present as well as in the future generations.     

Urodynamic Management of Neurogenic Bladder in Spinal Cord Injury

Background

A spinal cord injury is devastating and produces profound changes in the life style of the individual and his family. It is difficult to predict bladder and sphincter behaviour on the basis of clinical somatic neurological deficits.

Methods

A prospective study of 100 spinal cord injury patients was conducted to establish a bladder management protocol. The urodynamic variables were assessed frequently. Clean Intermittent Catheterization (CIC) along with antimuscarinic drugs was instituted and response monitored. Nonresponders were offered Intradetrusor Botulinum toxin.

Result

Spinal shock lasted for upto six months and only 8% could be converted to CIC during the acute phase. A total of 82% patients underwent three to four urodynamic studies which revealed an increase in cystometric capacity and a decrease in the maximum detrusor pressures. This lowered the incidence of incontinence episodes and prevented upper urinary tract damage. Botulinum toxin provided only temporary relief.

Conclusion

Aggressive management of neurogenic bladder (NB) dysfunction is a crucial component of the rehabilitation programme for spinal cord injury patients. Repeated urodynamic studies are an essential aid in managing the evolving nature of the bladder dysfunction. Meticulous bladder management protocol can prevent upper urinary tract complications.Key Words: Spinal cord injury, Neurogenic bladder, Urodynamics     

Effects of valproate on vestibular symptoms and electronystagmographic findings in migraine patients

OBJECTIVES: To investigate the effects of valproic acid on vestibular symptoms and electronystagmography (ENG) findings in patients with migraine-related vestibulopathy. METHODS: Thirty-seven patients with migraine (13 with vertigo, 13 with dizziness, and 11 without vestibular symptoms) were included in the study. Slow-released valproic acid (500 mg/d) was given for 3 months. Frequency of headache and vestibular symptoms in the first, second, and third months of the therapy were recorded and compared with the pretreatment values. The ENG findings were also evaluated before and 2 months after the therapy. RESULTS: We determined that prophylactic low-dose valproic acid decreased the frequency of headache and vestibular symptoms, although it does not cause any statistically meaningful change in ENG findings. CONCLUSIONS: Valproate can be used satisfactorily for patients with migraine who have vestibular complaints. Ineffectiveness of valproic acid on ENG findings can be clarified by the permanent effect of migraine on the vestibular system.