The newborn with seizures -- a follow-up study.

OBJECTIVE: To determine the sequelae of neonatal seizures in a cohort of newborns, recruited over a six month period. DESIGN: Prospective hospital based study. SETTING: The neonatal intensive care unit (NICU) of a tertiary care hospital. PARTICIPANTS: 135 babies were recruited of whom 10 died and 25 were lost to follow up. METHODS: The cases were followed up over four months. RESULTS: 68% of the babies followed up were normal; 32% had an abnormal neurological outcome. Seven (7%) developed post-neonatal epilepsy. Hypocalcemia was significantly associated with mortality (OR: 21.9; 95% CI: 1.2-391.2). No risk factors could be identified for post neonatal epilepsy. Presence of spike waves in the EEG was significantly related to abnormal neurological outcome (OR: 3.5; 95% C.I. 1.2-10.8). CONCLUSIONS: Majority of neonates with seizures have a normal outcome with no developmental delay or neurological deficit. Predominantly spike waves in the EEG is predictive of abnormal neurological outcome.

Callosal agenesis and Open lip Schizencephaly.

We report a case of a new born who presented with neonatal seizures; and who had coexistence of a Corpus Callosum Agenesis with a bilateral Open lip Schizencephaly and a Dandy Walker malformation. The investigations for an underlying etiology, however was futile.

Retinopathy of prematurity in VLBW and extreme LBW babies.

OBJECTIVE: This is a hospital-based, prospective clinical study to determine the incidence, risk factors, and outcome of extreme low birth weight and very low birth weight pre-term babies with retinopathy of prematurity (ROP) at the Sultan Qaboos University Hospital, Oman. METHODS: All babies with a birth weight =/< 1500 g and gestational age =/< 32 weeks admitted in the Neonatal Unit, were screened for ROP between 4 to 6 weeks of age and staged according to the international classification and were followed up until complete vascularization of the retina. Fifty nine babies formed the study group. RESULTS: The overall incidence of ROP was 25.4% (15 out of 59), of which 6 babies had severe ROP and underwent cryotherapy/laser. All babies with ROP had a birth weight < 1250 g and were born before 31 weeks of gestation. CONCLUSION: ROP is a multifactorial disease, the immature retina of the pre-term baby being the primary factor. Incidence and severity was inversely proportional to birth weight and gestational age. Multiple logistic regression analysis showed that sepsis and total parenteral nutrition to be highly significant risk factors. Repeated blood transfusions, hypotension and congenital heart disease with left to right shunt were seen to be considerably associated with the development of ROP. A decrease in overall incidence and severity of ROP was observed in this study.

High and low molecular weight proteolytic activities in prawn (Metapenaeus brevicornis) muscle.

Muscle extract of prawn (Metapenaeus brevicornis) expressed high azocoll lytic activity compared to extracts of many other prawn varieties; the activity was also inhibited to a small extent by dithiothreitol. Ammonium sulphate precipitation, subsequent extraction at pH 5.6 and chromatography revealed the occurrence of two types of azocoll lytic activities: one, high molecular weight (630 kDa) and the other low molecular weight (< 30 kDa) enzyme. The former was stimulated by dithiothreitol whereas the latter was inhibited. SDS PAGE of high molecular weight preparation did not show homogeneity but the profile was similar to that of the low molecular weight fraction. Gel filtration of high molecular weight enzyme following incubation at high pH revealed the formation of low molecular weight fractions having activity towards azocoll. Chymotrypsin-like activity associated with high molecular weight enzyme was also susceptible to dissociation by high pH. Azocoll lytic activity of both enzymes was strongly inhibited by 1,10-phenanthroline.

Effect of gamma irradiation on chemical and biological properties of lipopolysaccharide from Salmonella typhimurium.

Lipopolysaccharide (LPS) from S. typhimurium on exposure to gamma-radiation resulted in decrease in toxicity and was less mitogenic, Silver stained profiles of irradiated LPS on polyacrylamide gels revealed complete loss of its heteropolysaccharides which was confirmed further by analysing lipid A and LPS from Salmonella minnesota Re mutants on SDS-PAGE. Glucosamine and 2-keto 3-deoxy-octonate(Kdo) contents were significantly decreased on treatment. Lipid A obtained by removal of heteropolysaccharides from LPS was less toxic on exposure to gamma radiations.

Possible role of calcium dependent protein phosphorylation in the modulation of wound induced HRGP gene activation in potatoes after gamma irradiation.

Hydroxyproline rich glycoprotein (HRGP) gene is induced in both control and gamma irradiated potato tubers after wounding. The enhanced RNA synthesis in response to wounding correlated well with the accumulation of both HRGP gene transcripts and protein. Initially, the level of HRGP gene expression in gamma irradiated potatoes in response to wounding was 30% more than the corresponding controls. After post irradiation storage of 3-5 weeks, HRGP gene expression in response to wounding was significantly lower than the unirradiated samples. This low level of HRGP gene expression in irradiated potatoes was partially retrieved by 5 mM Ca2+ treatment. Prior treatment with trifluoperazine, a calcium channel blocker resulted in 35% reduction in wound induced HRGP gene expression in control potatoes, further providing evidence for the involvement of Ca2+ dependency for HRGP gene activation. A comparative study on in vivo protein phosphorylation induced by wounding in control and irradiated potatoes exhibited significant differences. A good correlation was observed in the modulation of phosphorylation and HRGP gene expression by Ca2+ in irradiated potatoes. Wound induced signal transduction system and subsequent Ca2+ dependent protein phosphorylation for the activation of HRGP gene is affected in potatoes after gamma irradiation, thus impairing the wound healing process adversely.

Aggregation of banana pyrophosphate fructose 6-phosphate 1-phosphotransferase by glycerol.

Addition of glycerol during purification of banana (Musaceae, Musa cavendishii) pyrophosphate fructose 6-phosphate 1-phosphotransferase [(PFP), EC 2.7.1.90] initiated molecular aggregation of the enzyme. The aggregation process was dependent on the glycerol concentration. The native enzyme (66 kDa molecular mass) showed enhanced activity at 3% (V/V) or less of glycerol concentration. Glycerol concentration between 4 and 5% (V/V) affected a gradual and sequential aggregation of native form of the enzyme. These aggregated forms had molecular masses of 135, 200 and 270 kDa. The 135 and 200 kDa forms were stable for about 72 hrs and prolonged storage over 2 weeks resulted in the formation of the 270 kDa form. Concentration over 5% could reduce the time required for aggregation. Fru2.6 bis P activated the enzyme over ten fold, but did not help in the aggregation process. Studies on the role of glycerol on PFP specific activity suggested a difference in the activation process compared to that by Fru2.6bis P. Replacement of Hepes buffer by Tris increased the Fru2.6 bis P requirement for maximum activation by around 10 fold. Removal of glycerol from the buffer media resulted in almost complete inactivation of the enzyme.

Activation of protease activity in rat peritoneal macrophages in protein deficiency: characterization of cathepsin D.

Rat peritoneal macrophages contained high proteolytic activity that was significantly enhanced under the stress induced by protein deficiency. The aspartyl protease cathepsin D which has been known to be the most active protease in endocytic processes was extracted from the macrophages recovered from control (20% protein fed) and protein deficient (4% protein fed) rats and was affinity purified and characterized further. The cathepsin D from the control sample exhibited better recovery, purification and higher specific activity compared to that from the deficient groups. Apparently the pH optima and heat stability of the enzyme from both the groups were similar. The SDS PAGE profile clearly indicated the presence of greater amounts of active forms of cathepsin D in the deficient samples in vivo itself which reflected in a reduction in Km value of the enzyme. Subtle differences observed in the activity of these macrophage proteases in the protein deficient rats may be partly responsible for the enhanced degradation of macrophage membrane proteins reported earlier.

Synthesis and phosphorylation of macrophage membrane proteins in protein deficient rat.

Changes in the biosynthesis and phosphorylation of rat peritoneal macrophage membrane proteins induced by protein malnutrition have been studied. The results clearly indicate that the biosynthesis of high molecular weight proteins (45-200 kDa) and their phosphorylation are significantly reduced in the macrophages isolated from protein deficient (4% protein-fed) rats compared to the control group fed 20% protein diet. Lipopolysaccharide (LPS) treatment both in vivo and in vitro enhanced the synthesis and phosphorylation of these proteins in both control and protein deficient groups; however, the extent of enhancement was much less in the deficient group. These results indicate that besides the down regulation of these membrane proteins, protein malnutrition seems to make these macrophages less responsive to potent immuno stimulants like LPS.

Newly synthesised mRNA as a probe for identification of wound responsive genes from potatoes.

A method for the selective isolation of wound induced RNA from potato tuber has been standardised by labeling with 4-thiouridine and subsequent affinity chromatography on Affigel 501 phenyl-mercury Sepharose column. About 30% of the total RNA isolated from wounded potato tissue was found to be synthesized de novo. The relative abundance of wound induced RNAs was confirmed by using two well identified wound inducible gene probes of hydroxyproline-rich glycoproteins (HRGP) and proteinase inhibitor I. The selectively separated wound induced mRNA was used to make cDNA probes. By screening a--gt10 cDNA library from wounded potato tissue with these cDNA probes, several wound responsive genes were identified. Wound inducible expression of these genes was further confirmed by Northern hybridization and their tissue specific expressions were examined. Thus, a simple method for the direct identification of wound responsive genes from potato was developed.

Enumeration of macrophage carbohydrates in protein-deficient rats: relation to cell surface properties.

In order to study the effect of protein malnutrition on macrophage glycoproteins the carbohydrate composition of peritoneal macrophages from protein-deficient rats has been studied by paper chromatography and HPLC. The results show that the carbohydrate content of resident cells recovered from protein-deficient group was significantly greater than control and decreased on prolonged incubation. In the protein-deficient samples there was a significant decrease in the content of galactose, fucose and galactosamine known to be binding to specific ligands and increase in glucose and mannosamine. In both control and deficient groups, thioglycollate (TG) elicitation resulted in higher total sialic acid content. Prolonged incubation (18 hr) caused an elevation of sialic acid levels in the resident cells, whereas a drastic reduction was observed in the TG elicited cells. In the protein-fed (20%) group, the cell surface sialic acid which contributes to the negative charge of the cells, reduced significantly on culturing the TG cells but not the resident cells. In the protein-deficient group, this effect was seen in the resident cells also; in the TG cells the cell surface sialic acid was significantly low at the isolation stage suggesting that these cells had become comparatively more positively charged in vivo itself. This observed reduction could be correlated to the enhanced sialidase levels in these cells. These protein deficiency related changes in the carbohydrate composition of macrophages could lead to modification of their receptor activity and charge related functions.