cDNA cloning and characterization of the human UDP glucuronosyltransferase, UGT1A3

The cDNA encoding the UDP glucuronosyltransferase, UGT1A3, has been cloned and expressed in cell culture. The deduced amino acid sequence of the cDNA is 90% similar in sequence to that of a previously characterized form, UGT1A4 and to that of a third form, UGT1A5 whose function in unknown. UGT1A3, when expressed in COS cells has a relative molecular mass of 55 kDa and is active in the glucuronidation of estrone and 2-hydroxyestrone. Activity towards other polyhydroxylated estrogens including 4-hydroxyestrogen and estriol and its metabolites was not detected. UGT1A3 was also inactive towards androgens and their metabolites. The enzyme preferentially glucuronidated the N-hydroxy metabolite of 2-acetylaminofluorence and was more active towards the 6- and 12-hydroxylated metabolites of benzo[alpha]pyrene. RNA encoding UGT1A3 was detected in human liver and colon tissue.

Two brc-abl junction peptides bind HLA-A3 molecules and allow specific induction of human cytotoxic T lymphocytes

Intracellular processing of the products of the bcr-abl junction region in CML Philadelphia chromosomes would generate novel peptides which, if they are capable of binding to HLA-class I molecules, would be potential targets of a cytotoxic T cell response. The 18 nonamers corresponding to the b2-a2 and b3-a2 fusions and differing from the parental bcr and abl sequences for at least one amino acid have been synthesized and tested for binding with HLA class I alpha chain preparations from HLA-homozygous B lymphoblastoid cell lines. Two peptides derived from the b3-a2 junction bound to HLA-A3 and elicited detectable specific CTL responses in vitro. The binding affinity of one of the two peptides could be increased by appropriate substitutions of the anchor residues with those of the known HLA-A3 anchor motifs. More important, the modified peptide had increased capacity to prime a specific CTL response in vitro. The interaction with HLA-A3 of these two peptides and their substitution derivatives seems to be promising for target trials aimed at eliciting a specific CD8 T cell response against CML.

H-RYK, an unusual receptor kinase: isolation and analysis of expression in ovarian cancer

BACKGROUND

Protein tyrosine kinases play an important role in cellular metabolism as key components of signal transduction pathways. They are involved in cellular growth, differentiation, and development. Receptor tyrosine kinases (EGF receptor and c-erbB2) have been shown to be important in the pathogenesis of cancer. In ovarian cancer, overexpression of c-erbB2, a type I receptor, has been correlated with an adverse effect on survival of patients.

MATERIAL AND METHODS

An unusual receptor tyrosine kinase, H-RYK, has been isolated from a complimentary DNA library of SKOV-3, an epithelial ovarian cancer cell line, using a polymerase chain reaction-mediated approach.

RESULTS

The primary structure of the predicted amino acid sequence of the protein shows a novel NH2-terminal region. The catalytic region shows homology to other tyrosine kinases, the closest homology being with v-sea (39%). A significant alteration in the catalytic domain is that the highly conserved "DFG" triplet in subdomain VII is altered to "DNA." The gene was mapped to chromosome 3q22. A single transcript of 3.0 kb is expressed in heart, brain, lung, placenta, liver, muscle, kidney, and pancreas by Northern analysis with maximal expression in skeletal muscle. In situ hybridization analysis on human tissues demonstrated localization of message in the epithelial and stromal compartment of tissues such as brain, lung, colon, kidney, and breast. There was minimal to absent expression of H-RYK on surface epithelium of ovaries. In benign (3) and borderline tumors of the ovary (5), there was expression in the stromal compartment. However, in malignant tumors (24) there was increased expression predominantly confined to the epithelium. Polyclonal antisera raised against synthetic peptides recognize a 100-kD protein in ovarian cancer cells and other cell lines. In contrast to other receptor tyrosine kinases, the receptor did not phosphorylate in an in vitro kinase assay.

CONCLUSIONS

The expression of this unusual receptor tyrosine kinase in epithelial ovarian cancer suggests that it may be involved in tumor progression, which needs further investigation.

Semantide- and chemotaxonomy-based analyses of some problematic phenotypic clusters of slowly growing mycobacteria, a cooperative study of the International Working Group on Mycobacterial Taxonomy

During previous cooperative numerical taxonomic studies of slowly growing mycobacteria, the International Working Group on Mycobacterial Taxonomy described a number of strains whose taxonomic status was ambiguous. A new study of DNA, RNA, and proteins from 66 of these organisms was performed to correlate their properties with phenotypic clustering behavior; the results of this study permitted 51 of the strains studied to be assigned to known species. The methods used to characterize the semantides included nucleotide sequencing and assessment of levels of semantide relatedness by affinity binding techniques, including whole DNA-DNA hybridization, probe hybridization, and antibody binding. There was good overall agreement between the phenotypic and chemotaxonomic clusters and the groups of organisms identified by semantide analyses. Our results supported the conclusion that we should continue to rely on polyphasic taxonomy to provide satisfactory systematic resolution of members of the genus Mycobacterium. We identified no single 16S rRNA interstrain nucleotide sequence difference value that unequivocally defined species boundaries. DNA-DNA hybridization remains the gold standard, but common resources are needed to permit DNA-DNA hybridization analyses to be made available to laboratories that are not prepared to use this technology. One of the large novel clusters which we studied corresponds to the recently described species Mycobacterium interjectum, a pathogen that resembles the nonpathogen Mycobacterium gordonae phenotypically. We also identified strains that appear to represent ribovars of Mycobacterium intracellulare which do not react with the commercial diagnostic probes that are currently used for identification of this species. Other branches or clusters consisted of too few strains to permit a decision about their taxonomic status to be made.

Rapid and simultaneous quantification of rhamnose, mannitol, and lactulose in urine by HPLC for estimating intestinal permeability in pediatric practice

Determination of intestinal permeability by measuring nonmetabolized sugars has been used to assess the integrity of intestinal mucosa. We have developed and validated a modified HPLC method for determining the concentration of L-rhamnose, mannitol, and lactulose in urine, using an amine-modified silica column and refractive index detection. Probe sugars are simultaneously resolved within 18 min. The calibration curve for each sugar is linear to 20 mmol/L. The minimum detectable concentration of lactulose is 0.05 mmol/L. Recovery of probe sugars is between 99.3% and 105.1%. Overall precision (CV) of estimation of probe sugars ranges from 4.2% to 6.5%. In 14 urine samples from healthy children who ingested the test solution containing 1 g of L-rhamnose, 1 g of mannitol, and 5 g of lactulose, the 5-h urinary excretion ratios of lactulose/rhamnose and lactulose/mannitol were 0.047 +/- 0.018 and 0.021 +/- 0.010 (mean +/- SD), respectively. This method presents a rapid, convenient, and practical technique for determining intestinal permeability in clinical pediatric practice.

Validation in rats of two biomarkers of exposure to the food-borne carcinogen 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP): PhIP-DNA adducts and urinary PhIP

2-Amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP)-DNA adducts in white blood cells and tissues and unmetabolized PhIP in urine were validated as biomarkers of exposure in male Fischer-344 rats treated with daily PhIP doses ranging from 1 to 0.0001 mg/kg. At the end of the 23 day treatment period all rats were killed and their blood and 10 tissues were collected for isolation of DNA and analysis of PhIP-DNA adducts by 32P-postlabeling and alkaline hydrolysis with GC/MS. PhIP-DNA adducts could be detected only in animals receiving 1 or 0.1 mg/kg/day, with highest adduct levels in the pancreas, heart and kidneys. There was a good correlation (r = 0.77, P < 0.005) between the two methods of analysis, with average adduct levels determined by 32P-postlabeling approximately 1.4 times higher than those determined by alkaline hydrolysis with GC/MS. PhIP-DNA adducts accumulated in most tissues, especially in the liver, kidneys, heart and pancreas, with lower levels in the white blood cells, small intestine, stomach, colon and cecum. Using GC/MS levels of unmetabolized PhIP were measurable in four weekly 24 h urine samples even at 0.0001 mg/kg/day, a dose comparable with reported human dietary exposure. A linear dose-response was obtained for excretion of unmetabolized PhIP across the range of doses, with approximately 1.8% of the dose excreted daily, largely independent of the number of doses. No PhIP was detected in the urine of untreated rats. If it can be shown that a constant percentage of PhIP is excreted unchanged in human urine, irrespective of dose, as has been found with the rat, measurement of urinary PhIP could be used as an accurate measure of dietary exposure to this amine in man.

Rapid and simultaneous quantification of rhamnose, mannitol, and lactulose in urine by HPLC for estimating intestinal permeability in pediatric practice

Determination of intestinal permeability by measuring nonmetabolized sugars has been used to assess the integrity of intestinal mucosa. We have developed and validated a modified HPLC method for determining the concentration of L-rhamnose, mannitol, and lactulose in urine, using an amine-modified silica column and refractive index detection. Probe sugars are simultaneously resolved within 18 min. The calibration curve for each sugar is linear to 20 mmol/L. The minimum detectable concentration of lactulose is 0.05 mmol/L. Recovery of probe sugars is between 99.3% and 105.1%. Overall precision (CV) of estimation of probe sugars ranges from 4.2% to 6.5%. In 14 urine samples from healthy children who ingested the test solution containing 1 g of L-rhamnose, 1 g of mannitol, and 5 g of lactulose, the 5-h urinary excretion ratios of lactulose/rhamnose and lactulose/mannitol were 0.047 +/- 0.018 and 0.021 +/- 0.010 (mean +/- SD), respectively. This method presents a rapid, convenient, and practical technique for determining intestinal permeability in clinical pediatric practice.

Linkage study of the D5 dopamine receptor gene (DRD5) in multiplex Icelandic and English schizophrenia pedigrees

OBJECTIVE

The authors investigated the possibility that genetic variation or mutation of the dopamine D5 receptor gene might modify susceptibility to schizophrenia.

METHOD

Twenty-three Icelandic and English pedigrees containing multiple cases of schizophrenia were genotyped by using a highly informative microsatellite for the D5 dopamine receptor gene DRD5.

RESULTS

By means of three different affection models, negative lod scores were obtained under assumptions of autosomal dominant and recessive inheritance. There was no evidence for locus heterogeneity. Nonparametric extended relative pair analysis also produced negative results.

CONCLUSIONS

These data indicate that mutations of the D5 dopamine receptor gene are not a major cause of schizophrenia in these pedigrees. Because of the probable existence of locus heterogeneity, the D5 receptor gene may be of etiologic importance in other families with schizophrenia.

Investigation by linkage analysis of the XY pseudoautosomal region in the genetic susceptibility to schizophrenia

BACKGROUND

A susceptibility locus for schizophrenia in the pseudoautosomal region has been proposed on the basis of a possible excess of sex chromosome aneuploidies among patients with schizophrenia and an increased sex concordance in affected sib pairs. Several studies investigating this hypothesis have produced conflicting evidence.

METHOD

In a series of Icelandic and British families, we used lod score and sib pair linkage analyses with markers for the MIC2 and DXYS14 loci on the pseudoautosomal XY region.

RESULTS

Lod and sib pair linkage analysis with these markers produced strongly negative scores. Heterogeneity testing also produced negative results.

CONCLUSION

We conclude that the present study provides no support for the involvement of either the pseudoautosomal region or the nearby region of the sex chromosomes in the aetiology of schizophrenia.

Linkage analysis of chromosome 22q12-13 in a United Kingdom/Icelandic sample of 23 multiplex schizophrenia families

A possible linkage to a genetic subtype of schizophrenia and related disorders has been reported on the long arm of chromosome 22 at q12-13. (Pulver et al., 1994: Am J Med Genet 54:36-43; Coon et al., 1994: Am J Med Genet 54:72-79; Pulver et al., 1994: Am J Med Genet 54:44-50). However formal statistical tests in a combined sample could not reject homogeneity and prove that there was a linked subgroup of families. We have studied 23 schizophrenia pedigrees to test whether some multiplex schizophrenia families may be linked to the microsatellite markers D22S274 and D22S283 which span the 22q12-13 region. Two point followed by multipoint lod and non-parametric linkage analyses under the assumption of heterogeneity provided no evidence for linkage over the relevant region.

Age and responses to the Love Attitudes Scale: consistency in structure, differences in scores

Two separate issues concerning the relation between age and love are addressed in this article. The first issue is concerned with the age generalizability of the factor structure produced by responses to the Love Attitudes Scale. The data presented indicate that the factor structure of responses to the Love Attitudes Scale is highly similar in college-aged and middle-aged participants. The second issue concerns the relation between age and actual scores on the sub-scales of the Love Attitude Scales. The data indicate that age is related to responses on the Mania and Agape sub-scales, particularly for females. Collectively, these data suggest that general structural conceptions of love remain relatively constant into middle-age, but that there is a relation between age and some specific love styles.

Superoxide dismutase activity in lymphoblastoid cells from motor neurone disease/amyotrophic lateral sclerosis (MND/ALS) patients

Point mutations in the gene encoding Cu,Zn superoxide dismutase (SOD1) are associated with autosomal dominant familial amyotrophic lateral sclerosis (FALS). We have measured Cu,Zn SOD activity in lymphoblastoid cells from affected and at risk FALS patients carrying mutations in the SOD1 gene, FALS patients without mutations in the SOD1 gene, individuals affected by the sporadic form of the disease (SALS), normal controls and individuals with other neurological abnormalities. The results show a significant decrease in Cu,Zn SOD activity in affected and at risk FALS individuals as compared to FALS patients without mutations, SALS individuals, normal and neurological controls. It is concluded that decreased SOD activity may contribute, together with other as yet unknown factors, to motor neurone demise.

Localization of an epithelial-specific receptor kinase (EDDR1) to chromosome 6q16

A protein receptor tyrosine kinase (EDDR1) has been isolated from a complementary DNA library of SKOV-3, an epithelial ovarian cancer cell line. The primary structure of the predicted amino acid sequence of the protein shows a novel N-terminal region that has homology to a factor VIII-like domain. The C-terminal catalytic domain has all of the canonical sequence motifs of a receptor tyrosine kinase with homology to the TRK-2H protein (49%), which suggests that it is a type II receptor. It is expressed in epithelial cells of several tissues. To determine the chromosomal localization of the gene, somatic cell hybrids were analyzed by PCR amplification using oligonucleotide primers specific for EDDR1. Segregation was observed to a hybrid containing human chromosome 6. Cosmids for EDDR1 were isolated from a human chromosome 6 cosmid library and were shown by fluorescence in situ hybridization to map to 6q16.

Weight concerns and dieting behaviors among high school girls in Israel

PURPOSE

The purpose of this study was to determine the prevalence of weight concerns and dieting behaviors among Israeli adolescent females, to compare the results with those found in other countries and with previous studies in Israel, and to compare the different ethnic groups within the study population.

METHODS

The study population included 341 tenth grade girls, mostly native-born, from three public high schools in Jerusalem, Israel. Girls completed a questionnaire, and anthropometric measures were taken within their respective schools.

RESULTS

Seventeen percent of the population was obese, however a much larger percentage expressed dissatisfaction with their body weights and shapes. Dieting for weight loss was common with 74% reporting past dieting and 47% reporting present dieting. No differences were found between the girls whose families originated in different countries. However mothers' weight concerns, as perceived by their daughters, did differ with higher concerns among the mothers who had come from Europe/America or who were born in Israel, than among those from North Africa or the Middle East.

CONCLUSIONS

Comparisons with earlier studies in Israel indicate a large increase in weight concerns and dieting behaviors, with prevalence rates similar to those reported in Western countries. The finding that among the girls, these maladaptive attitudes and behaviors crossed ethnic boundaries, suggests that adolescent girls have been acculturated into the dominant culture in which a strong emphasis is placed on thinness. The results suggest the need for educational programs and for further studies on different cultural and religious groups within Israel.

Isolation and characterization of an epithelial-specific receptor tyrosine kinase from an ovarian cancer cell line

A protein receptor tyrosine kinase (RTK 6) has been isolated from a complementary DNA library of SKOV-3, an epithelial ovarian cancer cell line, using a polymerase chain reaction (PCR)-mediated approach. The primary structure of the predicted amino acid sequence of the protein shows a novel NH2-terminal region which has homology to a factor VIII-like domain. The juxtamembrane region is proline and glycine rich and is the longest for any known receptor kinase. The COOH-terminal catalytic domain has all of the canonical sequence motifs of a receptor tyrosine kinase with homology to the TRK-2H protein (49%). A single transcript of 4.5 kilobases is expressed at low levels in heart, placenta, lung, liver, muscle, kidney, and pancreas, with high levels of expression in the brain. Ribonuclease protection assay showed a varying level of expression of message in a panel of eight ovarian cancer cell lines compared to placenta. In situ hybridization analysis demonstrated localization of mRNA in the epithelial cells of the ovary, kidney, small bowel, lung, thymus, and brain. There was a lower level of message in normal, benign, and borderline tumors of the ovary compared to malignant tumors of the ovary. Polyclonal antisera raised against a COOH-terminal synthetic peptide recognize a M(r) 140,000 protein in ovarian cancer cells, which autophosphorylates in an in vitro kinase assay.

Screening with the Alcohol use Disorders Identification Test (AUDIT) in an inner-city population

OBJECTIVES

1) To determine the operating characteristics of the Alcohol Use Disorders Identification Test (AUDIT) in an inner-city population and 2) to compare AUDIT performance with physician recognition of alcohol-related problems.

DESIGN

New patients were administered a health habits questionnaire, which included the AUDIT and the alcohol portion of the Structured Clinical Interview for DSM-III-R (used as the "gold standard" for alcohol abuse or dependence). The findings were compared with physician recognition based on chart review.

SETTING

Inner-city general medicine clinic staffed by resident physicians with faculty supervision.

PATIENTS/PARTICIPANTS

Consecutive new patients over a ten-week period. Of 166 consecutive new patients, 23 were not contacted, 17 refused to participate, two were excluded for gross cognitive deficits, and 124 completed the study.

RESULTS

Of the 124 patients, 41 (33%) met criteria for past or present alcohol abuse or dependence. The AUDIT correctly identified 26/27 (sensitivity of 96%) of patients with current problems and 0/14 of patients with past problems only. Physician rates of recognition of current and past alcohol-related problems based on chart review were 12/27 (sensitivity of 44%) and 1/14 (7%), respectively. The specificities of both the AUDIT and physician recognition were high, 96% and 99%, respectively.

CONCLUSIONS

1) Alcohol-related problems were common in this setting, 2) The AUDIT had a high sensitivity and a high specificity for detection of current alcohol problems in this setting, but it failed to detect patients with only past histories of alcohol problems. 3) The AUDIT performed significantly better than did the physicians in detecting alcohol problems. 4) The addition of an assessment of past alcohol use to supplement information from the AUDIT would appear to represent a promising screening strategy worthy of further investigation.

Sequence and structure similarities of cathepsin B from the parasite Schistosoma mansoni and human liver

A three-dimensional structure of Schistosoma mansoni cathepsin B was modelled using the coordinates of the crystal structure of the human liver enzyme. Both enzymes appear to share remarkable structural similarity. However, an examination of the models complexed with two synthetic inhibitors revealed differences in inhibitor binding, as confirmed by differences in the 50% inhibitory concentration of the same inhibitor.

The effects of educational placement and grade level on the self-perceptions of low achievers and students with learning disabilities

Previous studies have yielded mixed findings as to the effect of learning disabilities (LD) on self-perception. We proposed that perceived competence in children who experience learning difficulties is affected both by age trends in self-appraisal processes and by the degree to which students' salient reference group is composed primarily of similar or more competent others. Measures of perceived competence (Harter, 1982) and perceived achievement were administered to 222 Israeli students (127 boys, 95 girls) in Grades 3, 5, and 7. The sample comprised 68 children with LD attending special schools, 68 children with LD attending special classes in regular schools, and 86 nonidentified low achievers in regular classes. As expected, perceived competence was similar and high in all groups at Grade 3, but was higher among the special school group than among the special class and low achieving groups at Grade 5. The benefits of special schools were less clear at Grade 7. Implications for research methodology and educational practice are discussed.

The importance of secondary anchor residue motifs of HLA class I proteins: a chemometric approach

In this paper we report a chemometric approach to Quantitative Structure-Activity Relationship (QSAR) analysis applied to a study of the binding of peptides to Major Histocompatibility Complex (MHC) class I proteins. Peptides which possess the known primary anchor residue motif for HLA-B27 binding do not necessarily bind to HLA-B27 proteins. Secondary anchor residues are also involved, but it is not yet clear which amino acids are required or in which positions. A classic approach to this problem would be to synthesize multiple peptides each varying by a single amino acid from a starting peptide, and test them for their binding properties. Not only is this approach inefficient, but it is essentially unable to provide information about possible mutual interactions of amino acid residues in different positions. Using a statistical design to select the most informative compounds to use in the QSAR study, it was possible to analyse the effects on HLA-B27 peptide binding of different amino acids in four positions by means of only nine peptides. The relative binding activity of these peptides could then be modeled mathematically to provide information about the relative contribution of each of the four positions and to suggest a new peptide with high binding affinity. Our results demonstrate the usefulness of the chemometric strategy for studying peptides of interest in molecular immunology.

Genetic linkage of cone-rod retinal dystrophy to chromosome 19q and evidence for segregation distortion

Inherited retinal dystrophies are the most common cause of childhood blindness in the developed world. Cone-rod retinal dystrophies are severe examples of this group of disorders. Analysis of a large cone-rod dystrophy pedigree suggested that inheritance within the family was influenced by meiotic drive (p = 0.008), a rare segregation distortion in human genetics. Two-point linkage analysis showed significant linkage with three markers mapping to chromosome 19q. Multipoint analysis gave a maximum lod score of 10.08 (theta = 0.05) distal to D19S47. Cone-rod dystrophy is therefore assigned to 19q13.1-q13.2 and a new candidate locus for other retinal dystrophies is identified.

Anchor residue motifs of HLA class-I-binding peptides analyzed by the direct binding of synthetic peptides to HLA class I alpha chains

The binding characteristics of the primary anchor residue motifs reported for HLA-A2 (A*0201, A*0205) and HLA-B27 (B*2705) alleles were investigated by a direct binding assay of the pertinent synthetic peptides to HLA class I alpha chains derived from a panel of HLA homozygous B-cell lines of various HLA phenotypes, including four A2 subtypes. The assay is based on a serologic detection of the conformational change of HLA class I alpha chains induced by binding to specific peptides in the presence of beta 2m. It is applicable to test a large number of HLA allelic products and synthetic peptides. Assay data confirmed the high allele specificity of the anchor residue motifs tested, but also revealed the intra- and interlocus cross-reactivity of these motifs. In the case of A2 anchor motifs, not only a broad cross-reactivity within the A2 subgroup, but also cross-reactivities with A24, A26, A28, and A29 were observed. With B27 anchor motifs, an interlocus cross-reactivity with A3 and A31 was seen. Several peptides, even though they carried A2 or B27 major anchor residue motifs, failed to bind to the relevant alpha chains, suggesting that the presence of a primary anchor residue motif is necessary for HLA class-I-peptide binding but is not by itself sufficient to guarantee binding.