An echocardiographic study in patients with non haemorrhagic cerebral infarction to find cardiac abnormalities.

Background: Strokes are a major cause of morbidity and mortality worldwide. Majority are due to ischemic cerebral infarction. Ischemia may result from occlusion of blood vessels due to a disease process intrinsic to carotid and intracranial vessels or may relate to coexisting heart diseases, predisposing to embolic phenomenon. Objective: Echocardiographic study in patients with cerebrovascular accident, confirmed to be of non hemorrhagic nature on CT scan/MRI, for evidence of potential cardiac abnormalities as a predisposing cause for the vascular event. Material and Methods: An observational study was conducted in department of medicine, GNDH, Amritsar. 50 patients of ischemic stroke were taken and 2D transthoracic echocardiography was done to find potential cardioembolic abnormalities. Results: 76% of patients had echocardiographic abnormalities and 42% had potential cardioembolic abnormalities, out of which most common were ventricular wall hypokinesia, calcific aortic valve, rheumatic heart disease and dilated cardiomyopathy. The prevalence was almost similar in different age groups and both the sexes. Conclusion: Prevalence of potential cardioembolic abnormalities is high (42%) in ischemic stroke patients and 2D echocardiography is therefore recommended in the management and secondary prevention of cardioembolic stroke, which has a higher mortality and more chances of recurrence than atherothrombotic type of ischemic stroke.

Antibacterial efficacy of Nisin, Pediocin 34 and Enterocin FH99 against Listeria monocytogenes and cross resistance of its bacteriocin resistant variants to common food preservatives

Antilisterial efficiency of three bacteriocins, viz, Nisin, Pediocin 34 and Enterocin FH99 was tested individually and in combination against Listeria mononcytogenes ATCC 53135. A greater antibacterial effect was observed when the bacteriocins were combined in pairs, indicating that the use of more than one LAB bacteriocin in combination have a higher antibacterial action than when used individually. Variants of Listeria monocytogenes ATCC 53135 resistant to Nisin, Pediocin 34 and Enterocin FH99 were developed. Bacteriocin cross-resistance of wild type and their corresponding resistant variants were assessed and results showed that resistance to a bacteriocin may extend to other bacteriocins within the same class. Resistance to Pediocin 34 conferred cross resistance to Enterocin FH 99 but not to Nisin. Similarly resistance to Enterocin FH99 conferred cross resistance to Pediocin 34 but not to Nisin. Also, the sensitivity of Nisin, Pediocin 34 and Enterocin FH99 resistant variants of Listeria monocytogenes to low pH, salt, sodium nitrite, and potassium sorbate was assayed in broth and compared to the parental wild-type strain. The Nisin, Pediocin 34 and Enterocin FH99 resistant variants did not have intrinsic resistance to low pH, sodium chloride, potassium sorbate, or sodium nitrite. In no case were the bacteriocin resistant Listeria monocytogenes variants examined were more resistant to inhibitors than the parental strains.

A preliminary molecular study on protein profile of vital organs: A new direction for post mortem interval determination.

Estimation of the postmortem interval (PMI) is one of the most important tasks in Forensic Medicine. Six autopsy organ tissues such as brain, lungs, heart, liver, pancreas and kidney were taken at the time of forensic autopsy. All the proteins present in the tissues were extracted and the protein profile was analyzed on the sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) starting from 0 day to 10th day after death. The protein profiles showed a consistent degradation pattern which was consistent and reproducible in all the samples with respect to the time interval. In conclusion, the protein profile of the vital body organs appears to be a useful method for estimating the post mortem interval up to 10th day. Advantage of this approach over others is that it can detect the post mortem interval over a long interval (0 - 10 days) with an easily detectable pattern of protein profile.

Mercury induced modifications in the stereochemistry of the active site through Cys-73 in a serine protease--crystal structure of the complex of a partially modified proteinase K with mercury at 1.8 A resolution.

Proteinese K (PK) isolated from Tritirachium album Limber was crystallized with HgCl2 in excess, under microgravity conditions. The intensity data were collected at 4 degrees C to 1.8 A resolution and the final R-factor after refinement for all the reflections was 0.164. Mercury has been found at two sites with partial occupancies (0.4 and 0.6) which are at distances of 2.48 A and 2.58 A respectively from Cys-73 Sgamma. The Cys-73 in the enzyme structure is located close to the active site residue, His-69. This region is completely buried and is not accessible to the solvent. It is rather tightly packed. Therefore, the binding of mercury distorts the stereochemistry of the neighbouring residues including those belonging to the catalytic triad. As a result of this, the Ogamma of Ser-224 is displaced by 0.6 A which causes the inactivation of proteinase K by increasing the H-bond distance to 3.7 A between Ser-224 Ogamma and His-69 Nepsilon2.

Three-dimensional structure of a new form of mare lactoferrin in 70% PEG 400 at 3.8 A resolution.

Three-dimensional (3D) structure of a new form of diferric mare lactoferrin has been determined at 3.8 A resolution. The protein was crystallized in a space group P2(1)2(1)2(1) with a = 80.1 A, b = 103.7 A, c = 112.2 A with a solvent content of 57%. The structure was solved by molecular replacement method using the model of native mare lactoferrin. The structure has been refined using X-PLOR to a final R-factor of 22.6% for all the data in 15.0-3.8 A resolution range. The final refined model comprises 5281 protein atoms, 2Fe3+ and 2CO3(2-) ions. The protein folds into two globular N- and C-lobes. The two lobes are further divided into two domains N1, N2 in the N-lobe and C1, C2 in the C-lobe. The overall folding of the protein is similar to that observed for the native protein. The superposition of Calpha traces of native mare lactoferrin and the present structure gives an r.m.s shift of 0.7 A. There is a slight variation in the orientation of two lobes but the domain orientations in the present structure are identical to those observed in the native mare lactoferrin.

Enhancement of catalytic activity of enzymes by heating in anhydrous organic solvents: 3D structure of a modified serine proteinase at high resolution.

For the first time, it is demonstrated that exposure of an enzyme to anhydrous organic solvents at optimized high temperature enhances its catalytic power through local changes at the binding region. Six enzymes, namely, proteinase K, wheat germ acid phosphatase, alpha-amylase, beta-glucosidase, chymotrypsin and trypsin were exposed to acetonitrile at 70 degrees C for three hr. The activities of these enzymes were found to be considerably enhanced. In order to understand the basis of this change in the activity of these enzymes, proteinase K was analyzed in detail using X-ray diffraction method. The overall structure of the enzyme was found to be similar to the native structure in aqueous environment. The hydrogen bonding system of the catalytic triad remained intact after the treatment. However, the water structure in the substrate binding site underwent some rearrangement as some of the water molecules were either displaced or completely absent. The most striking observation concerning the water structure was the complete deletion of the water molecule which occupied the position at the so-called oxyanion hole in the active site of the native enzyme. Three acetonitrile molecules were found in the present structure. All the acetonitrile molecules were located in the recognition site. Interlinked through water molecules, the sites occupied by acetonitrile molecules were independent of water molecules. The acetonitrile molecules are involved in extensive interactions with the protein atoms. The methyl group of one of the acetonitrile molecules (CCN1) interacts simultaneously with the hydrophobic side chains of Leu 96, Ile 107 and Leu 133. The development of such a hydrophobic environment at the recognition site introduced a striking conformation change in Ile 107 by rotating its side chain about C alpha-C beta bond by 180 degrees to bring about the delta-methyl group within the range of attractive van der Waals interactions with the methyl group of CCN1. A similar change had earlier been observed in proteinase K when it was complexed to a substrate analogue, lactoferrin fragment.

Allogenic decalbone in glenoplasty for recurrent anterior dislocation of shoulder.

31 patients of recurrent anterior dislocation of shoulder treated by anterior glenoplasty using allogenic decalbone had good results. It is proposed that generalised congenital or developmental disorder may be an important etiological factor in pathogenesis of recurrence of the dislocation.

Circadian variations in circulating plasma sex steroids in female catfish, Clarias batrachus (Linn.).

Estradiol (E2) and 17 alpha-hydroxyprogesterone (17 alpha-OHP) levels exhibited significant circadian rhythms in the prespawning phase of the reproductive cycle. Pattern of rhythm was unimodal. Whereas, in the spawning phase E2 levels did not show significant fluctuations in their daily cycle whereas 17 alpha-OHP levels showed significant rhythm (P less than 0.001). Amplitude of rhythm of E2 was greater in prespawning phase while 17 alpha-OHP showed greater amplitude in spawning phase.

Pediatric hypertension: clinical profile and etiology.

Thirty six symptomatic hospitalized hypertensive children were evaluated for clinical profile and etiology. They were divided into two groups of 23 and 13 patients, respectively of chronic persistent hypertension and acute transient hypertension. Headache, failure to thrive, dyspnea and edema were common clinical features. Renal parenchymal pathology was the commonest etiology in both groups with a tubulo-interstitial pathology being more common amongst chronic hypertensives and acute glomerulonephritis in acute transient hypertensives. Essential hypertension was uncommon, found in only two patients with chronic hypertension reflecting probably an asymptomatic status of most patients with essential hypertension.

Kainic acid induced epileptogenesis in developing normal & undernourished rats--a computerised EEG analysis.

Experimental epilepsy was induced in developing normal, undernourished and subsequently rehabilitated rats by locally injecting graded doses of Kainic acid (KA) in the right frontal cortex. Frequency and power spectral analysis of EEG was carried out to assess the progressive changes in EEG during KA-epileptogenesis. Undernourished animals were highly susceptible to seizure discharge. They exhibited generalized tonic-clonic discharge and had episodes of clinical seizures even after temporary neuronal recovery. Increase in power of delta, theta and decrease in alpha power was observed in the compressed spectral array (CSA) of undernourished animals. Delayed neuronal recovery with reduced background EEG and marked electrosilence in response to intra-rectal sodium valproate was observed in undernourished animals. Rehabilitated animals exhibited partial recovery which was related to the body weight gain. Spike frequency, spike amplitude and neuronal recovery time were not significantly differet between normal and undernourished animals at lower doses of KA (7.5-60 ng) whereas at higher doses (120-500 ng) marked differences were observed in these parameters. In KA treated undernourished rats 3H-glycine incorporation was significantly higher than normal in the hippocampus and spinal cord and lower in the cerebellum.