Wilson's disease in children: 37-year experience and revised King's score for liver transplantation.

Wilson's disease (WD) is a rare liver-based disorder of copper metabolism. Prognostic criteria described by our group in 1986 to predict death without transplantation have not been universally validated. The clinical features of 88 children were reviewed, retrospectively in 74 and prospectively in 14. Data from the retrospectively recruited patients that died or survived on long-term chelation were used to evaluate the validity of our old scoring system and to devise a new prognostic index, then assessed in the 14 prospectively recruited patients. Using the old scoring system, 5 children scoring > or = 7, the cutoff value for death without transplantation, survived, whereas 4 scoring < or = 7 died (sensitivity 87% and specificity 90%). A new index based on serum bilirubin, international normalized ratio, aspartate aminotransferase (AST), and white cell count (WCC) at presentation identified a cutoff score of 11 for death and proved to be 93% sensitive and 98% specific, with a positive predictive value of 88%. When the new index was evaluated prospectively in 14 patients, it predicted the need for transplantation in only the 4 who required it, although 1 child with a score of 11 survived on medical treatment. In conclusion, the new Wilson Index is more sensitive and specific in predicting mortality without transplantation than the old scoring system, but needs to be validated in a larger number of patients.     

Mechanism of strength increase for a hydrothermal porcelain.

OBJECTIVES: The objectives of this study were to verify the formation of a hydrolyzed surface layer on Duceram LFC, to determine the effects of such a layer on mechanical material properties, and to identify a specific mechanism responsible for any strength increase observed. METHODS: Specimens were fabricated from dentin porcelain by a vibration blotting technique and were prepared to have either blunt or sharp surface flaws. Half of the specimens underwent accelerated aging. Specimens were fractured in three-point flexure to measure their strength, and fractographic analysis was used to determine fracture toughness and residual surface stress. Surface hardness and elastic modulus were measured using a microindentation method. Porcelain surface topography was examined using atomic force microscopy, and Fourier transform infrared spectroscopy was used to determine the composition of the surface layer. RESULTS: The aging treatment modified the porcelain surface topography but did not create a layer with increased hydroxyl ion content. Porcelain strength increased upon aging, and the increase was proportional to initial flaw severity. The apparent fracture toughness of sharp flaw specimens increased to match that for specimens containing blunt flaws upon aging. Surface hardness and elastic modulus decreased upon aging. SIGNIFICANCE: Previous studies on the strength increase of hydrothermal porcelain were contradictory because a variety of specimen preparation procedures were used. This study resolves the apparent contradiction by determining the effect of specimen preparation on material strength.     

Head and Neck Histoplasmosis—A Nightmare for Clinicians and Pathologists! Experience at a Tertiary Referral Cancer Centre

Histoplasmosis is a rarely reported deep mycotic infection in the Indian context. Oral or oropharyngeal manifestation can occur as an isolated symptom or as part of a disseminated process associated with immunosuppression especially with HIV and diabetes. Five cases of head and neck histoplasmosis accrued over 6 years in a tertiary referral cancer institute were reviewed. All these patients presented clinically as cancer. In three patients, the marked pseudoepitheliomatous hyperplasia led to a mistaken biopsy diagnosis of malignancy following which definitive surgical treatment was performed. The subsequent excision revealed typical features of histoplasmosis. Isolated oral presentation of histoplasmosis can mimic malignancy both clinically as well as pathologically, leading to potentially disastrous consequences. A high index of suspicion in those with overt or hidden immunosuppression and a deep wedge biopsy to demonstrate the organisms in the subepithelial tissue is recommended. This work has been presented in the “Slide seminar on Infections and Infestations” in the IAP-ID pre conference CME in APCON 2006.     

Oral cavity reconstruction: An objective assessment of function

The prime objective of oral cavity reconstruction is restoration of function, which must be carefully studied while evaluating the success of any reconstructive endeavour. We devised a unique comprehensive test series for the purpose that is suitable for use in routine follow-ups, and capable of providing objective documentation. Functional assessment included evaluation of general health, food intake, oral competence, mastication, speech, swallowing, tongue mobility, and shoulder–neck function. Fifty patients who had had surgery were analyzed and their functional scores compared with those of 10 normal volunteers. The extent of mandibular resection and the magnitude of soft tissue excision significantly affected overall scores of function. Oral competence, as reflected by the water holding test (WHT), was uniformly impaired in the 50 patients, and in dentate individuals, the quality of bolus provided good correlation with all other functional scores. Among reconstructive modalities employed here, the bi-paddled pectoralis major flap produced the best overall scores.     

Pattern of Sequence Variation Across 213 Environmental Response Genes

To promote the clinical and epidemiological studies that improve our understanding of human genetic susceptibility to environmental exposure, the Environmental Genome Project (EGP) has scanned 213 environmental response genes involved in DNA repair, cell cycle regulation, apoptosis, and metabolism for single nucleotide polymorphisms (SNPs). Many of these genes have been implicated by loss-of-function mutations associated with severe diseases attributable to decreased protection of genomic integrity. Therefore, the hypothesis for these studies is that individuals with functionally significant polymorphisms within these genes may be particularly susceptible to genotoxic environmental agents. On average, 20.4 kb of baseline genomic sequence or 86% of each gene, including a substantial amount of introns, all exons, and 1.3 kb upstream and downstream, were scanned for variations in the 90 samples of the Polymorphism Discovery Resource panel. The average nucleotide diversity across the 4.2 MB of these 213 genes is 6.7 × 10^-4, or one SNP every 1500 bp, when two random chromosomes are compared. The average candidate environmental response gene contains 26 PHASE inferred haplotypes, 34 common SNPs, 6.2 coding SNPs (cSNPs), and 2.5 nonsynonymous cSNPs. SIFT and Polyphen analysis of 541 nonsynonymous cSNPs identified 57 potentially deleterious SNPs. An additional eight polymorphisms predict altered protein translation. Because these genes represent 1% of all known human genes, extrapolation from these data predicts the total genomic set of cSNPs, nonsynonymous cSNPs, and potentially deleterious nonsynonymous cSNPs. The implications for the use of these data in direct and indirect association studies of environmentally induced diseases are discussed.     

DFNA54, a third locus for low-frequency hearing loss

Nonsyndromic hereditary hearing impairment (NSHHI) is a highly heterogeneous disorder with more than 90 loci mapped, of which nearly one-half of the responsible genes are identified. In dominant NSSHI hearing loss is typically biased towards the high frequencies while low-frequency hearing loss is unusual. Only two NSHHI loci, DFNA1 and DFNA6/14/38, are associated with predominantly low- frequency loss. We mapped the loci harboring the gene responsible for autosomal dominant low-frequency hearing loss in a multigenerational family. The pedigree of a Swiss family with low-frequency hearing loss was established. Using genomic DNA, DFNA1 and DFNA6/14/38 were excluded by linkage analysis or by direct sequencing of the responsible gene. Genome-wide linkage analysis was performed using commercially available microsatellite markers. Two-point linkage analysis demonstrated linkage to chromosome 5q31, the locus for DFNA15, with a lod score of 6.32 at recombination fraction =0 for marker D5S436. Critical recombinations were seen at markers D5S1972 and D5S410. Sequencing of the corresponding gene POU4F3 yielded no pathogenic mutation segregating with the affected members. In addition to Wolfram syndrome gene 1 (DFNA6/14/38) and diaphanous (DFNA1) there is evidence for a third gene involved in low-frequency hearing loss located at DFNA15. Because of the differences in auditory phenotype and the absence of pathogenic mutation in the coding region of POU4F3 it is likely that there is a second gene in 5q31, designated DFNA54, associated with NSHHI.     

Global molecular epidemiology of the O15:K52:H1 extraintestinal pathogenic Escherichia coli clonal group: evidence of distribution beyond Europe

Escherichia coli O15:K52:H1 is a significant extraintestinal pathogen in Europe (G. Prats et al., J. Clin. Microbiol. 38:201-209, 2000). To search for evidence of this clonal group outside of Europe, 75 non-European E. coli isolates of serogroup O15 were compared with five members of the O15:K52:H1 clonal group from Barcelona, Spain, according to genomic background, virulence genotypes, and antimicrobial resistance profiles. Amplification phylotyping showed that 16 (21%) of the 75 non-European O15 isolates corresponded with the O15:K52:H1 clonal group. The 16 non-European O15:K52:H1 clonal group members represented diverse geographic locales. They were isolated almost exclusively from humans with extraintestinal infections and accounted for 50% of all O15 isolates from five human clinical collections studied. Most non-European clonal group members exhibited a consensus virulence factor profile that included the F16 or F7-2 papA alleles (P fimbrial structural subunit), papG allele II (P fimbrial adhesin), iha (putative adhesin siderophore), and iutA (aerobactin receptor). This resembles the virulence profiles of (i) European representatives of the O15:K52:H1 clonal group and (ii) phylogenetically related "clonal group A," a recently recognized significant contributor to trimethoprim-sulfamethoxazole resistance in the United States (A. R. Manges et al., N. Engl. J. Med. 345:1007-1013, 2001). Antimicrobial resistance profiles were variable, and resistance was inconsistently transferred by conjugation. These findings indicate that the O15:K52:H1 clonal group is broadly distributed beyond Europe, exhibits previously unrecognized phenotypic and genotypic diversity, and contributes significantly to extraintestinal infections in humans.     

Tannic acid resistance in ruminal streptococcal isolates

Tannin degrading isolates of Streptococcus spp. from rumen of non-adaptive cattle, when grown in BHI broth, were able to tolerate tannic acid upto a level of 50 g/l. An increase in lag period from 1.5 to 6 h was observed for the isolates in presence of increased concentration of tannic acid. In addition, the morphology of gram positive diplococci converted to an elongated chain of 40-50 cells with increasing tannic acid from 1 to 4%. Qualitatively, the tannase activity was found to be present in the isolates tested, indicating their potential of being a tannin degrader.