In patients with a positive family history of familial adenomatous polyposis can the condition be diagnosed from the presence of congenital hypertrophy of the retinal pigment epithelium detected via an eye examination: A systematic review.

In classic familial adenomatous polyposis (FAP) adenomas become malignant. Congenital hypertrophy of the retinal pigment epithelium (CHRPE) is a retinal pigmented lesion and is the earliest and most common potential extraintestinal manifestation of FAP. This review aims to summarize and analyse all of the published data on CHRPE in patients with classic FAP and then ascertain whether these patients should undergo a relatively cheap and non-invasive dilated fundus examination to screen for CHRPE. Adhering to Preferred Reporting Items for Systematic Reviews and Meta Analyses guidelines our database search identified 102 relevant articles of which 13 were selected for further analysis. The percentage of FAP patients with CHRPE was found to be 80.00%, whereas the percentage of at-risk patients with CHRPE was 31.12%. Despite various statistically significant findings, CHRPE alone cannot be used as a surrogate for diagnosing FAP in those with a positive family history. The authors advocate a combined approach of eye examinations, colonoscopy and genetic testing.

Using Cellulolytic Nitrogen Fixing Bacterium, Azomonas agilis for Effective Degradation of Agricultural Residues.

INTRODUCTION: Azomonas agilis, a nitrogen-fixing bacterium, was isolated from rhizospheric soil in central Myanmar. METHODS & MATERIALS: The nitrogen-fixing activity of this bacterium was detected by plate screening method using glucose nitrogen free mineral medium and ammonium test-kit Cellulolytic activity was screened by plat assay and detected by Dinitrosalicyclic acid method (DNS). RESULTS & DISCUSSION: The isolated A. agilis grew in media containing 3-12% of NaCl, although the growth became poor when NaCl concentrations increased. Among various carbon sources, sucrose was the best source for ammonium accumulation of this bacterium, whereas arabinose was not the suitable carbon source. Although the nitrogen-fixing activity of A. agilis was highest after one week incubation, cellulase enzyme production was highest after 2-3 days of incubation. It was observed that cellulase enzyme activity of A. agilis for cellulose and sodium carboxymethyl cellulose (CMC) was almost the same. Three agricultural wastes were used to detect the cellulase enzyme activity of A. agilis, cellulase activity was better on filter paper as a substrate when compared to rice-straw and sawdust. CONCLUSION: So, the isolated A. agilis has high potential as an effective bacterial strain to use in sustainable agriculture and degradation of some agricultural residues.

Correction: Pathogenic waterborne free-living amoebae: An update from selected Southeast Asian countries.

[This corrects the article DOI: 10.1371/journal.pone.0169448.].

Pathogenic waterborne free-living amoebae: An update from selected Southeast Asian countries.

Data on the distribution of free-living amoebae is still lacking especially in Southeast Asian region. The aquatic environment revealed a high occurrence of free-living amoebae (FLA) due to its suitable condition and availability of food source, which subsequently causes infection to humans. A total of 94 water samples consisted of both treated and untreated from Laos (31), Myanmar (42), and Singapore (21) were investigated for the presence of pathogenic FLA. Each water sample was filtered and cultured onto non-nutrient agar seeded with live suspension of Escherichia coli and incubated at room temperature. Morphological identification was conducted for both trophozoites and cysts via microscopic stains (Giemsa and immunofluorescence). The presence of Naegleria-like structures was the most frequently encountered in both treated and untreated water samples, followed by Acanthamoeba-like and Vermamoeba-like features. To identify the pathogenic isolates, species-specific primer sets were applied for molecular identification of Acanthamoeba, Naegleria, and Vermamoeba. The pathogenic species of Acanthamoeba lenticulata and A. triangularis were detected from untreated water samples, while Vermamoeba vermiformis was found in both treated and untreated water samples. Our results suggested that poor water quality as well as inadequate maintenance and treatment might be the cause of this alarming problem since chlorine disinfection is ineffective in eradicating these amoebas in treated water samples. Regular monitoring and examination of water qualities are necessary in order to control the growth, hence, further preventing the widespread of FLA infections among the public.

Peripheral enzymatic deacetylation of chitin and reprecipitated chitin particles.

The enzymatic deacetylation of various chitin preparations was investigated using the fungal chitin deacetylase (CDA) isolated from Rhizopus oryzae growth medium. Specific extracellular enzyme activity after solid state fermentation was 10 times higher than that after submerged fermentation. Natural crystalline chitin is a very poor substrate for the enzyme, but showed a five-time better deacetylation after dissolution and reprecipitation. Chitin particles, enzymatically deacetylated for only 1% exhibited a strongly increased binding capacity towards ovalbumin, while maintaining the rigidity and insolubility of chitin in a moderate acidic environment. Because of the unique combination of properties, these CDA treated chitin materials were named "chit-in-osan". Chitinosan was shown to be an attractive matrix for column chromatography because no hydrogel formation was observed, that impaired the flow of eluent. Under the same conditions, partially deacetylated chitosan swelled and blocked the flow in the column.

Automated Registration of Multimodal Optic Disc Images: Clinical Assessment of Alignment Accuracy.

PURPOSE: To determine the accuracy of automated alignment algorithms for the registration of optic disc images obtained by 2 different modalities: fundus photography and scanning laser tomography. MATERIALS AND METHODS: Images obtained with the Heidelberg Retina Tomograph II and paired photographic optic disc images of 135 eyes were analyzed. Three state-of-the-art automated registration techniques Regional Mutual Information, rigid Feature Neighbourhood Mutual Information (FNMI), and nonrigid FNMI (NRFNMI) were used to align these image pairs. Alignment of each composite picture was assessed on a 5-point grading scale: "Fail" (no alignment of vessels with no vessel contact), "Weak" (vessels have slight contact), "Good" (vessels with <50% contact), "Very Good" (vessels with >50% contact), and "Excellent" (complete alignment). Custom software generated an image mosaic in which the modalities were interleaved as a series of alternate 5×5-pixel blocks. These were graded independently by 3 clinically experienced observers. RESULTS: A total of 810 image pairs were assessed. All 3 registration techniques achieved a score of "Good" or better in >95% of the image sets. NRFNMI had the highest percentage of "Excellent" (mean: 99.6%; range, 95.2% to 99.6%), followed by Regional Mutual Information (mean: 81.6%; range, 86.3% to 78.5%) and FNMI (mean: 73.1%; range, 85.2% to 54.4%). CONCLUSIONS: Automated registration of optic disc images by different modalities is a feasible option for clinical application. All 3 methods provided useful levels of alignment, but the NRFNMI technique consistently outperformed the others and is recommended as a practical approach to the automated registration of multimodal disc images.

Improvement of retinal function in L-ORD after prolonged dark adaptation.

OBJECTIVE: To describe the changes in dark-adapted (DA) retinal electrophysiological function after prolonged dark adaptation in a cohort of patients with late-onset retinal degeneration (L-ORD). DESIGN: Prospective case series. PARTICIPANTS: Nine patients with either stage 2 or 3 L-ORD. METHODS: International Society for Clinical Electrophysiology of Vision standard DA electroretinograms (ERGs) were performed before and after a period of extended dark adaptation (16 hours) in a cohort of patients heterozygous for the Ser163Arg mutation in C1QTNF5. RESULTS: Rod function was abnormal in 8 of 9 patients after standard (20 min) of dark adaptation. After extended dark adaptation, rod function normalized in 4 patients and there was a mean improvement in the DA 0.01 rod-specific ERG b-wave amplitude of 310% (p = 0.004). A significant improvement in DA 3.0 a-wave ERG amplitude localized the improvement in rod function at the level of the photoreceptor. CONCLUSIONS: This study demonstrates that a significant proportion of rod dysfunction in L-ORD can be reversed by extended dark adaptation and suggests that an abnormality of the visual cycle contributes to the pathogenesis of the disease. These findings would suggest that some retinal function could be restored, even in advanced cases of the disease if a suitable treatment is found.

Urinary NAG as an early indicator of renal damage in Russell's viper bite envenomation.

Urinary N-acetyl-beta-D-glucosaminidase (NAG; beta-N-acetylglucosaminidase; EC 3.2.1.30), blood urea, serum creatinine and creatinine clearance were measured in 23 patients bitten by Russell's viper (Daboia russelii siamensis), with systemic envenomation, at different time intervals after the bite during clinical observation for 5 d. Activities of urinary NAG were compared with these indicators of renal function in 3 clinical conditions: non-oliguric acute renal failure (ARF), oliguric ARF not requiring peritoneal dialysis, and oliguric ARF requiring peritoneal dialysis. Cut-off values to identify the 3 conditions were established. When the times of onset of the conditions, indicated by the cut-off values, were compared, urinary NAG was generally found to be the earliest indicator of renal damage. In each type of ARF, the urinary NAG level was abnormal before changes in the values of the other indicators of renal function. It may be possible to predict the types of ARF within 2 h after the bite by measurement of urinary NAG.

Renal involvement in Russell's viper bite patients without disseminated intravascular coagulation.

We measured urinary beta-N-acetylglucosaminidase (NAG: EC 3.2.1.30), blood urea, serum creatinine, albuminuria index and creatinine clearance in 16 patients bitten by Russell's viper (Daboia russelii siamensis) without disseminated intravascular coagulation (DIC) at the time of admission and then once daily for 5 d. Urinary NAG activity and the albuminuria index showed considerable variation whereas the other standard indicators of renal function revealed no abnormality. It is concluded that structural damage to the kidney occurred in these victims in the absence of DIC, indicating a direct toxic effect of Russell's viper venom on the kidney.

Effects of Russell's viper venom on renal lysosomal functions in experimental mice.

The lysosome-enriched fraction of mice kidney was isolated by homogenization and differential centrifugation. Lysosomal functions, namely lysosomal enzyme activities and membrane integrities were investigated in (a) the renal lysosome-enriched fraction, incubated with different concentrations of Russell's viper venom (RVV) for various time intervals (in vitro test) and (b) the kidney homogenate of mice, which had been envenomed with different dosages of RVV and been sacrificed after various time intervals post-envenomation (in vivo test). Three typical marker enzymes for lysosome were used, namely N-acetyl-beta-D-glucosaminidase (NAG), cathepsin D and acid phosphatase. It was found that, with increasing dosages of RVV and increasing time intervals after RVV treatment, the activities of all lysosomal enzymes generally increased and the lysosomal membrane integrities apparently reduced in in vitro and in vivo conditions, respectively. Among the three typical marker enzymes, NAG was found to be the most specific, sensitive and informative marker enzyme for the study of lysosomal functions in the kidney of mice treated with RVV.

Clinical trial of intramuscular anti-snake venom administration as a first aid measure in the field in the management of Russell's viper bite patients.

Efficacy of intramuscular anti-snake venom administration immediately after bite as a first aid measure in the field followed by standard hospital management versus standard hospital management alone in the therapy of Russell's viper bite patients was studied. There was a definite reduction in the number of patients with systemic envenomation, complications following disseminated intravascular coagulation and in fatality rate of Russell's viper bite victims who had received first aid intramuscular anti-snake venom prior to hospitalization when compared with those who had not.

Effect of enterotoxigenic Escherichia coli heat stable toxin on intestinal lysosomal enzymes in the suckling rat.

A preliminary study on 9 suckling Wistar rats, which received E. coli stable toxin, and on 12 sham-operated controls showed that acid phosphatase, the marker enzyme for lysosome, was significantly increased in the infected group whereas alkaline phosphatase, glucose 6-phosphatase, succinic dehydrogenase, and proteinase, the marker enzymes for brush border, microsome, mitochondria, and the soluble fraction, respectively, remained unaffected. The results suggest that lysosome, the subcellular organelle responsible for intracellular digestion could be modified by E. coli stable toxin. In another set of experiments, where 7 infected suckling rats and 7 sham-operated controls were used, the maximal activities of lysosomal enzymes (released by Triton X-100) were found to be increased in the infected group confirming the results obtained in the preliminary experiment. The values of the ratio between maximal and basal activity (an expression of the degree of retention of enzymes to lysosome) of acid phosphatase and cathepsin D were also significantly increased, indicating that lysosomal membrane may also be stabilized during the infection. The increased activities of lysosomal enzymes and the increased lysosomal membrane stability suggest that intracellular digestion by lysosome could be increased during E. coli stable toxin infection.

Effect of cholera toxin on L-[14C]glycine uptake and intestinal cell enzymes in rabbit.

The uptake of L-[14C]glycine and the activities of intracellular marker enzymes of enterocytes were studied in ligated small intestinal segments of rabbits during experimental cholera induced by intra-intestinal injection of pure cholera toxin (CT). No significant difference was observed in the active uptake of L-[14C]glycine between the CT-injected small intestinal segments and the saline-injected control segments, indicating that there is an intact active transport system for intestinal absorption of L-[14C]glycine during experimental cholera in rabbits. Apart from a significant increase in the activity of a brush border marker enzyme (alkaline phosphatase), there was no significant difference between the activities of marker enzymes for lysosomes (acid phosphate), microsomes (glucose-6-phosphatase), mitochondria (succinate dehydrogenase), and a cytosol enzyme (proteinase) in mucosal homogenates of CT-injected small intestinal segments compared to controls. The finding of an intact mitochondrial marker enzyme together with intact L-[14C]glycine absorption provides a scientific basis for considering the use of glycine and other monoamino monocarboxylic amino acids in "improved" oral rehydration solutions for the treatment of acute diarrhea, including cholera.

Decreased phosphodiesterase activity in cholera toxin-induced hypersecretion in suckling rats.

During cholera toxin (CT)-induced hypersecretion in suckling rats, the rise in the intestinal cAMP concentration was found to be accompanied by a decrease in the cAMP-phosphodiesterase activity. The results suggest the involvement of phosphodiesterase (PDE) as one of the factors governing the rise of cAMP.

Purification, characterization and biological activities of phospholipase A from Russell's viper (Vipera russelli) venom.

1. The major phospholipase A has been purified to electrophoretic homogeneity from the venom of Vipera russelli (Russell's viper). 2. The molecular weight of the purified enzyme was estimated to be 31,000 by Sephadex G-75 gel filtration chromatography and 29,000 by SDS-polyacrylamide gel electrophoresis. The enzyme exhibited an apparent Km value of 2.3 x 10(-2) M. 3. The phospholipase A showed edema forming, indirect hemolytic and myonecrotic activities but not hemorrhagic activity.

Intracellular distribution of radio-labelled enterotoxigenic Escherichia coli heat-stable toxin (STa) in the intestine of suckling rat.

The chloramine T-procedure was employed to radio-iodinate Escherichia coli heat-stable toxin (STa). The percentage iodination yield was 53.14% with a specific activity of 25.9 microCi/micrograms. Intragastric injections of both labelled and unlabelled toxin administered to suckling rats produced significant increase of fluid accumulation indicating that the biological activity of STa was not lost during radio-iodination. The uptake of the labelled toxin by subcellular particles of the intestinal cells in the suckling rats indicated that the toxin uptake was maximum in mitochondrial-lysosomal fraction. This confirms our previous observation on lysosomal involvement in digestion of the toxin. Results of the study also seem to be consistent with the short-lived hyper-secretory action of the toxin.

Clinical trial of berberine in acute watery diarrhoea.

Four hundred adults presenting with acute watery diarrhoea were entered into a randomised, placebo controlled, double blind clinical trial of berberine, tetracycline, and tetracycline and berberine to study the antisecretory and vibriostatic effects of berberine. Of 185 patients with cholera, those given tetracycline or tetracycline and berberine had considerably reduced volume and frequency of diarrhoeal stools, duration of diarrhoea, and volumes of required intravenous and oral rehydration fluid. Berberine did not produce an antisecretory effect. Analysis by factorial design equations, however, showed a reduction in diarrhoeal stools by one litre and a reduction in cyclic adenosine monophosphate concentrations in stools by 77% in the groups given berberine. Considerably fewer patients given tetracycline or tetracycline and berberine excreted vibrios in stools after 24 hours than those given berberine alone. Neither tetracycline nor berberine had any benefit over placebo in 215 patients with non-cholera diarrhoea.