Restoration of phytanic acid oxidation in Refsum disease fibroblasts from patients with mutations in the phytanoyl-CoA hydroxylase gene.

Refsum disease (RD) is biochemically characterized by the excessive accumulation of phytanic acid in tissues and body fluids due to deficiency of phytanoyl-CoA hydroxylase (PAHX). In this study, we screened three RD patients and identified a novel deletion (88 amino acids), and a missense mutation (Arg275Trp) in the previously reported PAHX cDNA (Jansen et al., 1997; Mihalik et al., 1997). Moreover, transfection of skin fibroblasts from two RD patients with wild-type PAHX gene restored the activity for alpha-oxidation of phytanic acid. Southern analysis on a somatic cell hybrid panel detected the PAHX gene on chromosome 10, corroborating radiation hybrid and homozygosity mapping data (Mihalik et al., 1997; Nadal et al., 1995).

Fetal cerebrohepatorenal (Zellweger) syndrome: dysmorphic, radiologic, biochemical, and pathologic findings in four affected fetuses.

Four fetuses with positive family histories for cerebrohepatorenal (Zellweger) syndrome (CHRS) underwent diagnostic amniocentesis or chorionic villus biopsy. Cultured amniocytes or fibroblasts from all of the fetuses displayed abnormal fatty acid ratios, and the parents elected therapeutic abortions. Dysmorphic features in one fetus consisted of micrognathia, proximal implantation of toes, and bilateral talipes equinovarus. Radiologic examination of the fetus confirmed the dysmorphic features and revealed foci of mineralization in the patellae. Biochemical analysis of three of the fetuses demonstrated markedly increased levels of very-long-chain fatty acids, both saturated and monounsaturated, in liver, kidney, adrenal, and brain. Pathologic findings consisted of premature mineralization of patellae; renal cystic tubular dilations; striated cells in adrenal fetal zone and testicular interstitium; dysplastic alterations of inferior olivary nuclei, dentate nuclei, and cerebral cortex; equivocal increases in portal fibrous tissue; and abnormal cytosomes in fetal zone adrenocortical cells, testicular and renal interstitial cells, and brain macrophages. Iron deposition, probably physiologic, was observed only in liver tissue. Distributions of immunoreactive catalase were identical in the fetuses with CHRS and age-matched control subjects. These findings document the accuracy of the prenatal diagnostic test and provide insights into the morphogenesis and pathogenesis of CHRS.

Microbial degradation of mefenoxam in rhizosphere of Zinnia angustifolia.

The fate of the fungicide mefenoxam was studied in a containerized rhizosphere system. The rhizosphere system used Zinnia angustifolia (Tropic Snow) in a bark/sand potting mix and was compared to bulk potting mix (no plants). Rhizosphere microbial populations were allowed to establish for 3 weeks prior to fungicide addition (20 microg per g mix). Mefenoxam and degradation product concentrations were determined by High HPLC or capillary electrophoresis after extraction. Seventy eight percent of the fungicide originally applied to the rhizosphere was degraded after 21 days compared to 44% in bulk system (no plant). The primary degradation product was the free acid N-(2,6-dimethylphenyl)-N-(methoxyacetyl)-DL-alanine, which accounted for 71% of the applied parent chemical after 30 days. N-(2,6-dimethylphenyl)-acetamide was also detected, but in lesser amounts. Bacterial populations in the rhizosphere increased during the 30-day period, which correlated with an increase in degradation of the parent compound. Pure cultures of Pseudomonas fluorescens and Chrysobacterium indologenes isolated from the rhizosphere system could degrade the applied fungicide (10 microg/ml) almost completely to the free acid within 54 h.

Cataract surgery in camp patients: a study on visual outcomes.

AIM: To assess the complications and visual outcomes associated with cataract surgery in camp patients operated at a tertiary centre. MATERIALS AND METHODS: In a retrospective study, 206 outreach camp patients had undergone cataract surgeries with posterior chamber intraocular lens implantation under peribulbar anesthesia over a period of 6 months. Post-operative complications on Day 1 were graded as per Oxford Cataract Treatment and Evaluation Team (OCTET) definitions. One month postoperative complications, best corrected visual acuity and refractive errors were assessed. RESULTS: 206 eyes underwent cataract extraction with PCIOL implantation. Small incision cataract surgery (SICS) was the commonest method (78.6%) used. The most common first post-operative day complication was mild iridocyclitis (26.2%). The complications were based on OCTET definitions, and showed that 33 % had Grade I and 3.4 % had Grade II complications. The major post-operative complication after 4 weeks of surgery was posterior capsular opacity. 89.8 % of the eyes had a 4 week-post-operative best corrected visual acuity of e± 6/24. The commonest refractive error was myopia with against the rule astigmatism, seen in 86 out of 150 cases. CONCLUSION: High quality cataract surgery with a low rate of intra-operative complications and good visual outcome can be attained in camp patients operated in the base hospitals, thus justifying more similar screening camps to clear the vast cataract backlog.