Isolation and characterization of Cu/Zn-superoxide dismutase in Fasciola gigantica.

A full-length complementary DNA (cDNA) encoding Cu/Zn-superoxide dismutase was isolated from Fasciola gigantica that on nucleotide sequencing showed a close homology (98.9%) with Cu/Zn-superoxide dismutase (SOD) of the temperate liver fluke, F. hepatica. Expression of the gene was found in all the three developmental stages of the parasite viz. adult, newly excysted juvenile and metacercaria at transcriptional level by reverse transcription-polymerase chain reaction (RT-PCR) and at the protein level by Western blotting. F. gigantica Cu/Zn-SOD cDNA was cloned and expressed in Escherichia coli. Enzyme activity of the recombinant protein was determined by nitroblue tetrazolium (NBT)-polyacrylamide gel electrophoresis (PAGE) and this activity was inactivated by hydrogen peroxide but not by sodium azide, indicating that the recombinant protein is Cu/Zn-SOD. The enzyme activity was relatively stable at a broad pH range of pH 4.0-10.0. Native Cu/Zn-superoxide dismutase protein was detected in the somatic extract and excretory-secretory products of the adult F. gigantica by Western blotting. NBT-PAGE showed a single Cu/Zn-SOD present in the somatic extract while three SODs are released ex vivo by the adult parasite. The recombinant superoxide dismutase did not react with the serum from buffaloes infected with F. gigantica. The role of this enzyme in defense by the parasite against the host reactive oxygen species is discussed.

Long-term contraception by a single silastic implant-D containing norethindrone acetate in women: a clinical evaluation.

PIP: 876 women were followed over a 3975-woman-month period after implantation of a single silastic capsule containing 40 mg of norethindrone acetate. Data were analyzed by a life-table method with 3 cut-off dates. Net cumulative pregnancy rate until 7 months was 2.3/100, whereas it rose to 3.9/100 after 8 months of implantation. Net cumulative termination rates rose from .7-10.9 at the end of 7 months and reached 13.6 after 8 months. Removal rates for planned pregnancy, personal, and medical reasons after 8 months were .6, 1.2, and 5.7, respectively. 1.4/100 requested implant removals in preparation for sterilization procedures. Expulsion occurred at a rate of .8/100 at the end of 8 months. The continuation rate was 86.4/100 after 8 months. Menstrual pattern abnormalities showed a reduction with time. This implant seems an acceptable long-term contraception alternative.^ieng

Serum and rectal mucosal zinc levels in acute and chronic diarrhea.

Serum and rectal mucosal zinc content was estimated in children (6-18 months old) with acute diarrhea (Group I: n = 50), chronic diarrhea (Group II: n = 25), extraintestinal infections (Group III: n = 15) and apparently healthy controls (Group IV: n = 20). The sex and nutritional status of various groups was comparable. The mean serum and tissue zinc levels in acute (p less than 0.001) and chronic (p less than 0.05 for serum; p less than 0.001 for tissue) diarrhea groups were significantly lower than healthy and infected controls. Group II had significantly lower (p less than 0.001) serum and rectal zinc content in comparison to Group I. There was a significant negative correlation between serum zinc and diarrheal duration (r = 0.5676; p less than 0.001). Repeat estimation at discharge in 38 patients (25 in Group I, 13 in Group II) revealed a significant reduction in both tissue and serum zinc and only tissue zinc in acute and chronic diarrhea, respectively. A total of 23 patients (16 in Group I, and 7 in Group II) were evaluated 2 weeks after discharge. After discharge, at recovery there was no alteration in serum zinc, but tissue zinc was marginally higher (p greater than 0.05). It is concluded that zinc depletion occurs in diarrhea, more so in the chronic state; with the continuation of diarrhea, depletion progresses; and there is a tendency for repletion during convalescence.

A simple in vitro method to detect singlet oxygen and to compare photodynamic activity using alkaline phosphatase.

A simple, sensitive and reliable in vitro method based on photodynamic inactivation of alkaline phosphatase to detect singlet oxygen and for evaluating relative photosensitizing efficiencies of photosensitizers such as hematoporphyrin (Hp) and phthalocyanines has been developed and compared with photobleaching of p-nitroso dimethyl aniline (RNO) and photooxidation of L-tryptophan. Inactivation of alkaline phosphatase is dependent both on light fluence and sensitizer concentration. Scavengers like mannitol and azide anion indicated the involvement of singlet oxygen in the deactivation of alkaline phosphatase, since azide anion provided concentration dependent protection whereas mannitol had no effect and that compared to ordinary water, photoinactivation of alkaline phosphatase was three times higher in 65% D2O. Alkaline phosphatase appears to be resistant to free radical attack (particularly to OH radicals) since hydrogen peroxide alone or in presence of ferrous ions did not reduce the enzyme activity and mannitol or azide anion gave no significant protection when alkaline phosphatase was irradiated with Co-60 gamma rays up to 2 K Gy. With the present method using red light, the chloroaluminium phthalocyanine sulphonates prepared by sulphonation showed higher and the corresponding condensation product lower photodynamic activity; Hp being intermediate and Mn- and Gd-phthalocyanines had no photodynamic activity.

Luffa aegyptiaca (Gourd) Fruit Juice as a Source of Peroxidase.

Peroxidases have turned out to be potential biocatalyst for a variety of organic reactions. The research work reported in this communication was done with the objective of finding a convenient rich source of peroxidase which could be used as a biocatalyst for organic synthetic reactions. The studies made have shown that Luffa aegyptiaca (gourd) fruit juice contains peroxidase activity of the order of 180 enzyme unit/mL. The K(m) values of this peroxidase for the substrates guaiacol and hydrogen peroxide were 2.0 and 0.2 mM, respectively. The pH and temperature optima were 6.5 and 60°C, respectively. Like other peroxidases, it followed double displacement type mechanism. Sodium azide inhibited the enzyme competitively with K(i) value of 3.35 mM.

Serum and rectal mucosal magnesium status in acute and chronic diarrhoea.

Serum and rectal mucosal magnesium content was estimated in children (6-18 months old) with acute diarrhoea (Group I: n = 50), chronic diarrhoea (Group II: n = 25), extra-intestinal infections (Group III: n = 15) and healthy controls (Group IV: n = 20). The sex and nutritional status of the different groups were comparable. The mean serum magnesium levels in acute and chronic diarrhoea were comparable to healthy and infected controls. The tissue magnesium content of infants with chronic diarrhoea was significantly (P less than 0.001) lower than other groups. Repeat estimation at discharge in 38 patients (25 in Group I, 13 in Group II) revealed a significant reduction in serum levels in both groups (P less than 0.05 and P less than 0.01, respectively) and in tissue levels in acute diarrhoea (P less than 0.05). A total of 23 infants (16 in Group I) were evaluated 2-3 weeks after discharge. There was an increase in tissue magnesium content at recovery in acute (P less than 0.02) and chronic (P greater than 0.05) diarrhoea groups. It is concluded that infants with chronic, but not acute diarrhoea, are magnesium depleted at presentation; with the continuation of diarrhoea there is a progressive depletion of magnesium; and there is a tendency to regain the magnesium status during the convalescent period.

Serum and rectal mucosal copper status in acute and chronic diarrhea.

Serum and rectal mucosal copper content was estimated in children (6-18 months old) with acute diarrhea (group I: n = 50), chronic diarrhea (group II: n = 25), extraintestinal infections (group III: n = 15), and apparently healthy controls (group IV: n = 20). The sex and nutritional status of various groups was comparable. The mean serum copper levels in acute diarrhea and infected control groups were comparable, but significantly (p less than 0.001) greater in comparison to chronic diarrhea and healthy control groups. The tissue copper in group II was significantly (p less than 0.001) lower than other groups, which were comparable. There was a significant negative correlation between serum copper and diarrheal duration (r = -0.615; p less than 0.001). Repeat estimation at discharge in 38 patients (25 in group I and 13 in group II) revealed a significant (p less than 0.05) reduction in the serum and tissue copper content during this period. Among the 23 infants (16 in group I and 7 in group II) evaluated 2-3 weeks after discharge, there was an increase in copper values of tissue alone (p less than 0.05) in group I and both serum and tissue (p less than 0.05) in group II. It is concluded that elevation of serum copper in acute diarrhea is a nonspecific response to infection; infants with chronic but not acute diarrhea are copper depleted at presentation; and with the continuation of diarrhea, there is a progressive depletion of copper.

Oral zinc supplementation in persistent diarrhoea in infants.

A controlled randomized trial was conducted in 40 infants (6-18 months old) with persistent diarrhoea (greater than 2 weeks' duration) to evaluate the effect of oral zinc supplementation. After completion of rehydration, 20 infants in group A received oral zinc sulphate (20 mg elemental zinc twice daily) and an equal number in group B were given a placebo (glucose). Each child was given oral nalidixic acid and a similar milk-free feeding schedule. Both the groups were comparable with respect to various initial characteristics including nutrition, diarrhoeal disease, serum alkaline phosphatase and serum and rectal mucosal zinc content. During therapy, all the assessed parameters of zinc status (serum alkaline phosphatase and serum and rectal zinc) recorded significant elevation and reduction in groups A and B, respectively. At recovery, the zinc status of group A was significantly higher than that of group B. The diarrhoeal duration and frequency in the zinc-supplemented group were lower but the differences were not statistically significant (p = 0.078 and p = 0.076, respectively). Weight gain in both groups was comparable. It is concluded that in persistent diarrhoea there is depletion of zinc with the progression of disease and oral zinc administration can improve the zinc status. The possible anti-diarrhoeal effect of zinc, however, merits further study.

A controlled trial on utility of oral zinc supplementation in acute dehydrating diarrhea in infants.

A controlled, randomized trial was conducted in 50 infants with acute dehydrating diarrhea to evaluate the effect of oral zinc supplementation in acute diarrhea. After completion of rehydration, 25 infants in Group A received oral zinc sulfate (20 mg elemental zinc twice daily) and an equal number in Group B were given placebo (glucose). Both groups were comparable with respect to various initial characteristics including nutritional status, diarrheal disease, serum alkaline phosphatase, and serum and rectal mucosal zinc content. During therapy all the assessed parameters of zinc status (serum alkaline phosphatase and serum and rectal zinc) recorded significant elevation and reduction in Groups A and B, respectively. At recovery the zinc status of Group A was significantly better and was nearer that of healthy controls. The diarrheal duration and frequency in the zinc-supplemented group were lower, but the differences were not significant (0.05 less than p less than 0.1). However, when only subjects with relatively severe initial zinc depletion (rectal zinc lower than the 15th percentile of healthy controls; 11 in Group A and 14 in Group B) were considered, the diarrheal duration and frequency were significantly (p less than 0.05 and p less than 0.01, respectively) lower in the zinc-supplemented cases. Weight gain in both groups was similar. It is concluded that oral zinc administration in acute diarrhea can replenish body zinc status and this may shorten the diarrheal duration and frequency in children with relatively severe zinc depletion.

Effect of alloxan diabetes and phenformin on insulin binding with liver plasma membrane receptors.

Effect of phenformin on [125I]insulin binding with the liver plasma membrane of normal and alloxan diabetic rats was studied in vitro. Diabetic rats showed a decreased binding of [125I]insulin with liver plasma membrane indicating thereby a decreased binding affinity of insulin with its receptors. Phenformin caused an increased binding of [125I]insulin with liver plasma membrane in normal as well as in diabetic rats. Results of this study indicate that the control of diabetes by phenformin is possibly affected by increasing the binding of insulin with plasma membrane receptors which in turn promotes insulin dependent metabolic reactions at the cellular level.