Free radical induced damages to rat liver subcellular organelles: inhibition by Andrographis paniculata extract.

Aqueous extract of Andrographis paniculata was examined for antioxidant activity using rat liver subcellular organelles as model systems. The study deals with two important biological oxidative agents, ascorbate-Fe(+2) and AAPH generating hydroxyl and peroxyl radical, respectively. Oxidative damage was examined against the inhibition of membrane peroxidation, protein oxidation and restoration in decreased SOD and catalase activity. The antimutagenic activity of Ap was examined following inhibition in AAPH induced strand breaks in plasmid pBR322 DNA. Extract was a potent scavenger of DPPH, ABTS radicals, exemplified by ESR signals, O2-*, *OH and H2O2, displayed excellent reducing power, FRAP potentials to reduce Fe (III) --> Fe (II) and had considerable amount of phenolics/ flavonoids contents, an effective antioxidant index. The observed antioxidant effect might be primarily due to its high scavenging ability for ROS. Effect was confirmed ex vivo following inhibition in peroxidation, restoration in SOD enzyme, SOD band intensity and protein degradation in Ap fed liver homogenate. Based on these results, it was concluded that the aqueous extract of Andrographis paniculata might emerge as a potent antiradical agent against various pathophysiological oxidants.

Peroxynitrite: a potent oxidizing and nitrating agent.

Nitric oxide (NO*) reacts with superoxide (O2-*) forming peroxynitrite (PXN) (ONOO-), a strong oxidant which reacts with several biomolecules leading to enormous implications in biological process, holds enormous implications for the understanding of free radicals. The ONOO- formation in vivo has significant implications in free radical biology. It exerts a defensive role in large number of pathophysiological reactions and also acts as signaling molecule in activation of several protooncogenes. It decomposes rapidly to an intermediate and reacts with several biomolecules. Evidence for PXN formation in vivo has been obtained immunohistochemically through detection of a characteristic reaction product with protein tyrosine residues and 3-nitrotyrosine. This "biomarker" of PXN formation has now been identified in various pathologies such as Lou Gehrig's disease, Parkinson's disease, cancer, atherosclerosis as well as in biological aging. 3-nitrotyrosine formation has been documented in various tissues, e.g. even in non-diseased embryonic heart during normal development. Therefore, there is a great opportunity in the postgenomic period to understand the interplay of these molecular interactions with biological events such as apoptosis, gene regulation etc. This review deals with biological significance of peroxynitrite, its precursors, reactions with large range of biomolecules, including aminoacids, proteins, lipids, nucleic acids, antioxidants as well as cytotoxic aspects.

Immunological response to two hepatitis B vaccines administered in two different schedules.

OBJECTIVES: To evaluate the antibody response to a plasma derived hepatitis B vaccine containing pre-S and S antigens and a recombinant vaccine containing only S antigen and compare the two vaccines in 0, 1, 2 and 0, 1, 6, schedules METHODS: One hundred fifty nine healthy infants were randomized to receive the vaccines in two different schedules. Anti HBs titers were estimated prior to the vaccination and then one-month following the second and third doses. RESULTS: Both the vaccines produced a high rate of seroconversion and seroprotection. The antibody response was similar with both the vaccines and the 0, 1, 6, schedule induced a significantly higher antibody level than the 0, 1, 2, schedule. CONCLUSION: 0, 1, 6 schedule produces a higher antibody level than 0, 1, 2 schedule though both the schedules have good seroconversion and seroprotection rates with both the vaccines.

Necrotizing myelitis in an immunocompetent child: a case report with review of literature.

A few cases of necrotizing myelitis have been reported in adults since its first description in 1973. No case has been described in the pediatric age group. A 12-year-old boy, who presented with acute flaccid paraplegia, loss of sphincter control and sensory loss showed features suggestive of necrotizing myelitis on magnetic resonance imaging. Investigations carried out could not reveal a specific etiological or pre-disposing factor. No clinical improvement occurred despite the therapy.

An unusual case of biliary atresia.

Intrahepatic biliary cysts are rarely seen in the patients with biliary atresia. We describe a ten-month-old child with biliary atresia in whom the abdominal imaging studies (ultrasonography, computed tomographic scan and magnetic resonance cholangiopancreatography) revealed multiple intrahepatic biliary cysts ('bile lakes'). The child also had intrapulmonary shunting of blood due to pulmonary arteriovenous fistulae, which were demonstrated on contrast-enhanced echocardiography. Both these findings, 'bile lakes' and pulmonary arteriovenous fistulae occur rarely in biliary atresia.

Infantile tremor syndrome and zinc deficiency.

Infantile tremor syndrome is characterized by coarse tremors, mental and physical retardation, light colored brown hair, skin pigmentation and anemia. Amongst the theories proposed for the etilogy of the disorder, the nutritional theory is most accepted. In this case report, we have presented a fourteen-month-old male child with ITS and documented zinc deficiency. Though most of the previous workers have proposed vitamin-B12 deficiency as the etimology for ITS, our report suggests that zinc deficiency could also have a causative role.

Pulmonary arteriovenous malformations.

Pulmonary arteriovenous malformations rarely present in childhood. Two cases are presented in this report. Both the cases presented clinically with cyanosis and clubbing without a cardiac murmur. The second case had cerebral abscess in addition. Both the cases underwent a contrast-enhanced echocardiography which suggested the presence of pulmonary arteriovenous malformations. The first case also underwent 99mTc radionuclide scan and pulmonary angiography. The cases are being reported for their characteristic clinical features and for emphasizing the role of non-invasive modalities like contrast-enhanced echocardiography and radionuclide scan in reaching the diagnosis.

Glanzmann's thrombasthenia.

Glanzmann's thrombasthenia (GT) is an uncommon cause of bleeding in children. We diagnosed two siblings as having GT on the basis of flow cytometric studies. Both had cutaneous bleedings and epistaxis since early childhood. Hematological investigations revealed prolonged bleeding time and a normal platelet count. Both the patients had absence of aggregation of platelets with the agonist adenosine diphosphate. Absence of the GPIIb/IIIa receptor was confirmed by flow cytometry. A short review of the disorder is presented.

Chloroquine induced parkinsonism.

A case of parkinsonism is reported in a 5-years-old male child following prolonged use of chloroquine. The patient presented with reduced spontaneous movements and speech with an expressionless face and a parkinsonian gait but no tremors. His investigations including CT scan brain, CSF study and serum ceruloplasmin were normal. Chloroquine was discontinued and the patient was started on oral trihexyphenidyl. The patient showed gradual recovery and the drug was successfully withdrawn. The toxic manifestations were only transient and reversible.

Rheumatic fever in children.

Rheumatic fever (RF) and rheumatic heart disease (RHD) are major public health problems in developing countries. A prospective study carried out in a large general hospital showed that carditis was the predominant feature in first attack and also the recurrence of RF but that recurrence was associated with more severe manifestations. Echocardiography picked up cases of subclinical carditis. Presence of congestive cardiac failure in association with carditis always led to chronic RHD. Recurrence occurred only when patient defaulted penicillin prophylaxis. The overall recurrence rate was 0.026 per patient.

Leptospirosis - an under-diagnosed clinical condition.

Leptospirosis is a zoonotic disease caused by leptospiral spirochaete. Two cases in children are described presenting with hepatorenal dysfunction.

Effect of passively transferred anti-poliovirus antibodies on seroconversion.

A prospective study enrolling 50 mother-infant pairs was undertaken to determine the effect of maternal antibodies on poliovirus antibody titres and seroconversion rates in infants and to determine the difference in titres and seroconversion rates following three and five doses of oral poliovaccine (OPV). Cord blood samples and samples collected 4 weeks after 3rd and 5th doses of trivalent oral poliovaccine were processed for estimation of anti-poliovirus antibody titres. These were expressed as geometric mean titres (GMT). Significance was analyzed using unpaired 't' test. The relationship between maternal antibody titres and seroconversion was determined by correlation coefficient test. Post OPV5 titres were significantly higher than post OPV3 titres for type 1 and type 2 polioviruses. Seroconversion rates against type 1, 2 and 3 polioviruses were 92.9%, 100.0% and 92.9% following OPV3 and 100.0%, 100.0% and 93.2% following OPV5. The cord blood titres did not have any relation to post-OPV3 or post-OPV5 titres. Although there is significant passive transfer of poliovirus antibodies across the placenta, this does not affect titres achieved after immunization. Post-OPV5 titres against type 1 and type 2 viruses are significantly higher than post-OPV3 titres. The seroconversion rates following OPV5 are higher than those obtained post-OPV3 but this difference is not statistically significant.