bluuebunny/crossref_metadata_2025 huggingface dataset:
Introduction of the non‐indigenous amphipod Gammarus pulex alters population dynamics and diet of juvenile trout Salmo trutta
Authors: KELLY DAVID W. , DICK JAIMIE T. A.
Published: December 2004

Summary 1. The amphipod Gammarus pulex, introduced to Irish rivers with the aim of enhancing trout feeding, is displacing the native Gammarus duebeni celticus. These two species are generally associated with different environmental conditions and macroinvertebrate communities, confounding assessment of effects of the invader as compared with the native on fish populations. Here, we uncouple effects of the two Gammarus species from environmental gradients.

2. A weir dissects a lowland stretch of the River Lissan, slowing the upstream invasion by G. pulex and resulting in contiguous G. pulex, mixed species and G. d. celticus reaches. Total invertebrate abundance and biomass in the benthos were significantly higher in the G. pulex reach, driven by high invader abundance, with low abundance of other taxa. Gammarus pulex was particularly prominent in night‐time drift.

3. Correspondingly, densities and biomass of 0+ trout were significantly higher in the G. pulex reach, while instantaneous loss rates were lower. Fish growth rates were similar among the three reaches.

4. In the G. pulex reach, this invader dominated the diet of 0+ trout, leading to ingestion of significantly higher invertebrate biomass than fish in the other reaches. Fish generally preyed on Gammarus in proportion to its abundance, but exhibited some positive selection for G. pulex in the invaded reach.

5. The negative effects of the invader on native invertebrates are contrasted with positive effects on juvenile trout. This indicates changes in energy flux after invasion, with differential resource use or assimilation by G. pulex probable underlying mechanisms. As the frequency of amphipod invasions increases globally, investigations of their role as strong interactors at multiple levels of ecological organisation is required if the consequences of deliberate and unintentional introductions are to be predicted, and ultimately, prevented.
The effectiveness of psychotherapeutic interventions for people with learning disabilities: a critical overview
Authors: Willner P.
Published: December 2004

Historically, people with learning disabilities have had little or no access to psychotherapeutic interventions, although there are signs that, over the past decade, this situation has seen some gradual improvement. This paper provides an overview of the evidence for the effectiveness of psychodynamic, cognitive‐behavioural and cognitive therapies in this client group. The available data support the position that all three approaches can be effective in people with mild learning disabilities and in a proportion of people with more severe conditions. However, the literature reporting outcomes of psychotherapeutic interventions in people with learning disabilities is extremely limited, and there is a conspicuous and unjustified poverty of randomized controlled trials. There is also very little evidence regarding either the importance of specific components of therapeutic packages, or the optimal manner of delivering these interventions to people with learning disabilities.
Emotional and behavioural needs of children and adolescents with intellectual disabilities in an urban conurbation
Authors: Emerson E. , Robertson J. , Wood J.
Published: December 2004

Background  Over the past decade, increased attention has been paid to identifying and responding to the emotional and behavioural needs of children and adolescents with intellectual disability (ID). The aims of the present study were to add to this body of knowledge by identifying factors associated with emotional and behavioural needs among a sample of children with ID drawn from a large urban conurbation.

Method  Information was collected by postal questionnaire (or interview for family carers who did not have English as their first language) from teachers and from family carers of 615 children administratively identified as having ID (47% of all children with ID).

Results  Results indicated that: (1) the administrative prevalence of moderate but not severe ID was associated with social deprivation whereas the prevalence of severe but not moderate ID appeared to be associated with ethnicity; (2) 54% of children scored above the threshold on the Developmental Behaviour Checklist (DBC)–primary family carer, and 37% of children scored above the threshold on the DBC‐teacher; (3) social deprivation, male gender, less severe ID and having fewer physical or sensory impairments were associated with antisocial and disruptive behaviour; and (4) more severe ID and additional impairments were associated with anxiety, communication disturbance, social relating and self‐absorbed behaviours.

Conclusions  These results identify a range of risk factors associated with behavioural and emotional problems experienced by children with ID.
Psychiatric symptoms of children and adolescents with juvenile neuronal ceroid lipofuscinosis
Authors: Bäckman M. L. , Santavuori P. R. , Åberg L. E. , Aronen E. T.
Published: December 2004

Background  Juvenile neuronal ceroid lipofuscinosis (JNCL) is one of the most common neurodegenerative disorders in childhood and adolescence. The clinical picture includes diverse and complex psychiatric symptoms that are difficult to treat. Only symptomatic treatment is available. To improve symptomatic therapy, it is important to recognize the symptoms. The purpose of this study was to identify predominant psychiatric symptoms in patients with JNCL.

Methods  The study included 27 patients with JNCL with and without psychotropic treatment. The mean age was 15.2 (range 9–21) years. Characteristic psychiatric symptoms in this patient group were clarified by using the following standardized questionnaires filled in by parents, teachers and the patients themselves: Child Behavior Checklist (CBCL), Teacher Report Form (TRF) and Children's Depression Inventory (CDI). The symptoms were recorded for the entire study group and compared between patients with and without psychotropic treatment and between genders.

Results  The patients had a large number of psychiatric symptoms according to the CBCL and TRF. The most commonly reported symptoms were social, thought, attention problems, somatic complaints and aggressive behaviour. Patients receiving psychotropic medication had more psychiatric symptoms according to the CBCL and TRF. Moreover, female patients had more problems than male patients according to the CBCL. The total psychiatric symptom score was at clinical or borderline range for psychiatric disturbance in 74% of patients. The number of depressive symptoms reported by the patients themselves was low.

Conclusions  JNCL patients suffer from a multitude of psychiatric symptoms. To improve drug choice and dosage, a thorough evaluation of these symptoms by standardized methods is needed before initiating treatment. Progress and possible adverse effects of treatment should be monitored on a regular basis.
Health, healthcare utilization and psychiatric disorder in people with intellectual disability in Taiwan
Authors: Lin J. D. , Yen C. F. , Li C. W. , Wu J. L.
Published: December 2004

Objectives  The aims of the present study were to examine health characteristics and healthcare utilization in relation to people with intellectual disability (ID) having psychiatric disorders in Taiwan.

Methods  A cross‐sectional study was employed; study subjects were recruited from the National Disability Registration Database. Taiwan, stratified by administrative geographical area for the study. Statistical analysis of 1026 carers for people with ID was made to examine the health status and healthcare utilization of individuals with ID having psychiatric disorders.

Results  Approximately 12.1% of people with ID had psychiatric disorders. These individuals were more likely to be poorer in health condition and consuming more medical services (in the outpatient, inpatient and emergency care areas), than those individuals without psychiatric disorders. These individuals with psychiatric disorders were also taking medicines regularly at a far greater percentage than did those without psychiatric disorders.

Conclusions  Given the high prevalence of psychiatric disorders among individuals with ID, the healthcare system should take further steps to develop an appropriate health status monitoring system and community‐based and easily accessible mental health services for them.
Human enamel erosion in constant composition citric acid solutions as a function of degree of saturation with respect to hydroxyapatite
Authors: BARBOUR M. E. , PARKER D. M. , ALLEN G. C. , JANDT K. D.
Published: December 2004

summary  The objective of this study was to investigate human enamel erosion under constant composition conditions, as a function of solution degree of saturation (DS) with respect to hydroxyapatite. The experimental conditions were relevant to the initial stages of enamel erosion by soft drinks. Nanoindentation was used to compare enamel surface softening caused by a control mineral water and two citric acid solutions with DS = 0·000 and DS = 0·032, both having pH 3·30. Enamel hardness and reduced elastic modulus were measured after 0, 30, 60, 120, 300 and 600 s exposure. A statistically significant change in enamel hardness was detected after 30 s exposure to both citric acid solutions, indicating that nanoindentation is extremely sensitive to the initial stages of erosion. There was a statistically significant difference between the mechanical properties of enamel exposed to the two citric acid solutions after 30, 60 and 120 s. At these times, the solution with DS = 0·000 caused twice as much enamel softening as that with DS = 0·032. This demonstrates that it may be possible to design a soft drink with a low erosive potential and a good taste by a small change in DS, at a typical drink pH.
Effect of Tuf‐Coat on Feldspathic porcelain materials
Authors: SEHA MIRKELAM M. , PAMUK S. , BALKAYA M. C. , AKGÜNGÖR G.
Published: December 2004

summary  Ion exchange has been shown to increase the fracture strength of not only industrial glasses but also dental porcelains. Tuf‐Coat, an ion exchange material, has been introduced as a simple method to strengthen dental porcelain restorations. Our experimental investigation aims to evaluate the effect of the ion exchange (Tuf‐Coat) on the flexural strengths of specimens made with Vita VMK 68, Ceramco veneer, IPS and Matchmaker body porcelain. Eighty specimens were fabricated as discs 13 mm in diameter and 2 mm thick according to manufacturers’ recommendations. Specimens were tested using a universal testing machine with a crosshead speed of 0·5 mm/min. by a method of biaxial flexural strength test. The results were evaluated using one‐way variance analysis and ‘Student's t’ test to compare results at P < 0·05 level. Among the porcelains tested only Vita VMK 68 has been statistically affected by the ion exchange method Tuf‐Coat.
The auxin transport inhibitor response 3 (tir3) allele of BIG and auxin transport inhibitors affect the gibberellin status of Arabidopsis
Authors: Desgagné‐Penix Isabel , Eakanunkul Suntara , Coles Jeremy P. , Phillips Andrew L. , Hedden Peter , Sponsel Valerie M.
Published: December 2004

The Arabidopsis gene BIG (formerly DOC1/TIR3/UMB1/ASA1) is known to encode a huge calossin‐like protein that is required for polar auxin transport (PAT). Mutations at this locus, in addition to reducing PAT, can alter the sensitivity of plants to several hormones and light. The tir3‐1 allele of BIG reduces the response of plants to application of the gibberellin (GA) precursors ent‐kaurenoic acid and GA12 and its semidwarf phenotype is partially reversed by C19‐GAs. The effects of auxin transport inhibitors (ATIs) on GA 20‐oxidation was examined in wild‐type and tir3‐1 seedlings. 1‐N‐naphthylphthalamic acid (NPA) and triiodobenzoic acid lead to overexpression of the GA‐biosynthetic gene AtGA20ox1 comparable in magnitude to the overexpression observed in seedlings treated with paclobutrazol, a GA biosynthesis inhibitor. In contrast to that of AtGA20ox1, overexpression of AtGA20ox2 is pronounced only in paclobutrazol‐treated Col and Ler, and is less in tir3‐1 and in all NPA‐treated seedlings. Thus the effects of BIG and ATIs on the expression of genes encoding GA 20‐oxidases are complex, and suggest that at least in some tissues ATIs, directly or indirectly, may reduce the level of bioactive GA and/or alter GA signal transduction.
The receptor‐like MLO protein and the RAC/ROP family G‐protein RACB modulate actin reorganization in barley attacked by the biotrophic powdery mildew fungus Blumeria graminis f.sp. hordei
Authors: Opalski Krystina S. , Schultheiss Holger , Kogel Karl‐Heinz , Hückelhoven Ralph
Published: December 2004

Cytoskeleton remodelling is a crucial process in determining the polarity of dividing and growing plant cells, as well as during interactions with the environment. Nothing is currently known about the proteins, which regulate actin remodelling during interactions with invading pathogens. The biotrophic powdery mildew fungus Blumeria graminis f.sp. hordei (Bgh) invades susceptible barley (Hordeum vulgare L.) by penetrating epidermal cells, which remain intact during fungal development. In contrast, resistant host plants prevent infection by inhibiting penetration through apoplastic mechanisms, which require focusing defence reactions on the site of attack. We stained actin filaments in a susceptible Mlo‐genotype and a near‐isogenic race‐non‐specifically resistant barley mlo5‐mutant genotype using fluorescence‐labelled phalloidin after chemical fixation. This revealed that the actin cytoskeleton is differentially reorganized in susceptible and resistant hosts challenged by Bgh. Actin filaments were polarized towards the sites of attempted penetration in the resistant host, whereas when susceptible hosts were penetrated, a more subtle reorganization took place around fungal haustoria. Strong actin filament focusing towards sites of fungal attack was closely associated with successful prevention of penetration. Actin focusing was less frequent and seemingly delayed in susceptible wild‐type barley expressing the susceptibility factor MLO. Additionally, single cell overexpression of a constitutively activated RAC/ROP G‐protein, CA RACB, another potential host susceptibility factor and hypothetical actin cytoskeleton regulator, partly inhibited actin reorganization when under attack from Bgh, whereas knockdown of RACB promoted actin focusing. We conclude that RACB and, potentially, MLO are host proteins involved in the modulation of actin reorganization and cell polarity in the interaction of barley with Bgh.
An Arabidopsis NPR1‐like gene, NPR4, is required for disease resistance
Authors: Liu Guosheng , Holub Eric B. , Alonso Jose M. , Ecker Joseph R. , Fobert Pierre R.
Published: December 2004

The Arabidopsis genome contains six NPR1‐related genes. Given the pivotal role played by NPR1 in controlling salicylic acid (SA)‐mediated gene expression and disease resistance, functional characterization of other family members appears to be justified. Reverse genetics was used to analyze the role of one NPR1‐like gene, which we called NPR4. The NPR4 protein shares 36% identity with NPR1 and interacts with the same spectrum of TGA transcription factors in yeast two‐hybrid assays. Plants with T‐DNA insertions in NPR4 are more susceptible to the virulent bacterial pathogen Pseudomonas syringe pv. tomato DC3000. This phenotype is complemented by expression of the wild type NPR4 coding region. As determined by the parasite reproduction, the npr4‐1 mutant is more susceptible to the fungal pathogen Erysiphe cichoracearum, but does not differ markedly from wild type in its interaction with virulent and avirulent strains of the oomycete Peronospora parasitica. In leaves of wild‐type plants, NPR4 mRNA levels increase following pathogen challenge or SA treatment, and decrease rapidly following methyl jasmonic acid (MeJA) treatment. Transcripts of the pathogenesis‐related (PR) genes PR‐1, PR‐2, and PR‐5 are only marginally reduced in the npr4‐1 mutant following pathogen challenge or SA treatment. This reduction of PR gene expression is more pronounced when leaves are challenged with the bacterial pathogen following SA treatment. Expression of the jasmonic acid‐dependent pathway marker gene PDF1.2 is compromised in npr4‐1 leaves following application of MeJA or a combination of SA and MeJA. These results indicate that NPR4 is required for basal defense against pathogens, and that it may be implicated in the cross‐talk between the SA‐ and JA‐dependent signaling pathways.
Genomic changes in synthetic Arabidopsis polyploids
Authors: Madlung Andreas , Tyagi Anand P. , Watson Brian , Jiang Hongmei , Kagochi Trevor , Doerge Rebecca W. , Martienssen Robert , Comai Luca
Published: December 2004

Polyploids are common and arise frequently by genome duplication (autopolyploids) or interspecific hybridization (allopolyploids). Neoallopolyploids display sterility, lethality, phenotypic instability, gene silencing and epigenetic changes. Little is known about the molecular basis of these phenomena, and how much genomic remodeling happens upon allopolyploidization. Extensive genomic remodeling has been documented in wheat, but little remodeling occurs in cotton. Newly synthesized Arabidopsis allopolyploids, which display phenotypic instability and low fertility, displayed several, possibly related mechanisms that can remodel genomes. We detected transcriptional activity of several transposons although their transposition was limited. One represents a new family of conditionally active En‐Spm‐like transposons of Arabidopsis thaliana, which underwent remodeling of CG methylation upon allopolyploidization. A random amplified fragment length polymorphism survey suggested remodeling at few, specific loci. Meiotic analyses revealed the appearance of chromosomal fragments in a substantial fraction of anther meiocytes. In several individuals produced by hybrids between the synthetic and a natural allopolyploid pollen viability inversely correlated with meiotic instability. Activity of selected DNA transposons and the possibly related chromosomal breaks could cause changes by inducing translocations and rearrangements.
Detection of RAG mutations and prenatal diagnosis in families presenting with either T–B– severe combined immunodeficiency or Omenn's syndrome
Authors: Tabori U , Mark Z , Amariglio N , Etzioni A , Golan H , Biloray B , Toren A , Rechavi G , Dalal I
Published: December 2004

It has been recently shown that mutations in both of the recombination activating genes RAG1 and RAG2 are involved in each of the two different types of severe combined immunodeficiency (SCID) syndromes: T–B– SCID and Omenn's syndrome (OS). The objective of the study was to search for novel mutations in the RAG genes and to offer prenatal diagnosis for families that have been identified as at risk of T–B– SCID or OS. Mutation analyses of polymerase chain reaction products of RAG1/RAG2 genes were performed in 14 cases (T–B– SCID = 6 and OS = 8). Consanguinity was reported in seven (50%) families. Four missense mutations in the RAG2 gene in six of eight OS patients and in four of six T–B– SCID patients were detected. The C1845T transition leading to a Tre215Ile substitution is a novel mutation. All but one of the patients were homozygous for the detected mutations, possibly reflecting the consanguinity in these families and the relative rarity of the disease‐causing mutations. In addition, three putative polymorphic sites were found. Prenatal diagnosis was offered to seven families, but three of them declined genetic counseling for religious reasons. In the remaining families, four pregnancies were successfully completed, and in one case, the family chose to have an abortion because of a homozygous mutation. Mutations in RAG1/RAG2 genes were detected in only some of the T–B– SCID or OS patients, and the molecular basis for the remaining cases has yet to be elucidated. Important factors such as religious beliefs need to be considered when offering prenatal diagnosis to certain families.
Low frequency of myocilin mutations in Indian primary open‐angle glaucoma patients
Authors: Sripriya S , Uthra S , Sangeetha R , George RJ , Hemamalini A , Paul PG , Amali J , Vijaya L , Kumaramanickavel G
Published: December 2004

Glaucoma is one of the major causes of blindness in the Indian population. Mutations in the myocilin (MYOC) gene have been reported in different populations. However, reports on MYOC mutations in Indian primary open‐angle glaucoma (POAG) patients and juvenile open‐angle glaucoma (JOAG) patients are sparse. We therefore screened 100 unrelated POAG/JOAG patients for MYOC mutations. Patients with POAG/JOAG were clinically diagnosed. Genomic DNA from such patients was collected and studied for MYOC mutations by direct sequencing. Nucleotide variations were compared with unrelated healthy controls by restriction enzyme digestion. Secondary structure prediction for the sequence variants was performed by Chou–Fasman method. A novel mutation in exon 1 (144 G→Α) resulting in Gln48His substitution was observed in 2% of the patients. Four other polymorphisms were also observed. The novel mutation was seen in four other affected family members of a JOAG patient. The novel mutation was found to alter the secondary structure in the glycosaminoglycan initiation site of the protein. MYOC mutations were found in 2% of the population studied. MYOC gene may not be playing a significant role in causing POAG in the Indian population.
The frequency of GJB2 and GJB6 mutations in the New York State newborn population: feasibility of genetic screening for hearing defects
Authors: Fitzgerald T , Duva S , Ostrer H , Pass K , Oddoux C , Ruben R , Caggana M
Published: December 2004

In the US, approximately one in every 1000 children has hearing loss sufficiently severe to interfere with the acquisition of normal speech [Ann NY Acad Sci 630 (1991) 16]. The causes of non‐syndromic hearing loss (NSHL) are known to be heterogeneous, with genetic factors accounting for 50–75%[Am J Med Genet 46 (1993) 486]. Often individuals with NSHL thought to be caused by mutations in GJB2 have only one detectable mutant allele [Am J Hum Genet 62 (1998) 792, Hum Mol Genet 6 (12) (1997) 2173]. Another gene that has been identified as a possible cause of NSHL is GJB6 that codes for the gap junction protein, connexin 30. A consecutive series of anonymous newborn dried blood specimens (n = 2089) was tested for two GJB2 mutations: (i) 35delG, a pan‐ethnic mutation; and (ii) 167delT, a mutation more frequently found in individuals of Ashkenazi Jewish and Mediterranean descents. Mutation detection was validated using allele‐specific oligonucleotide hybridization in single wells. Once the positive samples had been identified, the samples were pooled and retested. All positives in the individual experiment were correctly identified in the pooled experiment. The same random set of anonymous newborn dried blood specimens plus some additional samples were tested (n = 2112) for the 342‐kb deletion in the GJB6 gene.
Evidence for single origins of 35delG and delE120 mutations in the GJB2 gene in Anatolia
Authors: Tekin M , Boğoclu G , Arican ST , Orman MN , Tastan H , Elsayed S , Akar N
Published: December 2004

Eighteen different sequence changes, including three novel alterations, were detected in GJB2, encoding connexin 26, in 371 Turkish probands with non‐syndromic sensorineural hearing loss. Two frequently detected mutations, 35delG and delE120, were shown to have single origins based on the conserved genotypes of two closely linked microsatellite and five single nucleotide polymorphism markers. Carrier frequencies of 35delG and delE120 in Egypt and Turkic populations of the Near East provide insights about the origin of these two mutations.
Mutations in endoglin and in activin receptor‐like kinase 1 among Danish patients with hereditary haemorrhagic telangiectasia
Authors: Brusgaard K , Kjeldsen AD , Poulsen L , Moss H , Vase P , Rasmussen K , Kruse TA , Hørder M
Published: December 2004

Hereditary haemorrhagic telangiectasia (HHT) is a rare disorder with one per 6000–10,000 affected individuals in the general Caucasian population. HHT is genetically heterogeneous, involving at least two loci HHT1 mapping to chromosome 9q34.1 and HHT2 mapping to chromosome 12q31. The loci have been identified as endoglin (ENG) and activin receptor‐like kinase 1 (ALK1). In order to gain knowledge of the genotype distribution and prevalence in the Danish population and to establish a reproducible and sensitive molecular genetic test method, we developed a denaturating gradient gel electrophoresis protocol for mutation scanning of the two loci. Twenty‐five Danish HHT families were tested. A total of eight new as well as seven previously reported mutations were identified. A founder mutation was characterized present in seven families and possibly introduced around 350 years ago. In one individual, a presumed spontaneous mutation was characterized. The method developed proved to be very sensitive for mutation detection in both ENG and ALK1. Genetic screening in HHT families facilitates an early treatment strategy for silent HHT manifestations in first degree relatives.
FMR1 alleles in Tasmania: a screening study of the special educational needs population
Authors: Mitchell RJ , Holden JJA , Zhang C , Curlis Y , Slater HR , Burgess T , Kirkby KC , Carmichael A , Heading KD , Loesch DZ
Published: December 2004

The distribution of fragile X mental retardation‐1 (FMR1) allele categories, classified by the number of CGG repeats, in the population of Tasmania was investigated in 1253 males with special educational needs (SEN). The frequencies of these FMR1 categories were compared with those seen in controls as represented by 578 consecutive male births. The initial screening was based on polymerase chain reaction analysis of dried blood spots. Inconclusive results were verified by Southern analysis of a venous blood sample. The frequencies of common FMR1 alleles in both samples, and of grey zone alleles in the controls, were similar to those in other Caucasian populations. Consistent with earlier reports, we found some (although insignificant) increase of grey zone alleles in SEN subjects compared with controls. The frequencies of predisposing flanking haplotypes among grey zone males FMR1 alleles were similar to those seen in other Caucasian SEN samples. Contrary to expectation, given the normal frequency of grey zone alleles, no premutation (PM) or full mutation (FM) allele was detected in either sample, with only 15 fragile X families diagnosed through routine clinical admissions registered in Tasmania up to 2002. An explanation of this discrepancy could be that the C19th founders of Tasmania carried few PM or FM alleles. The eight to ten generations since white settlement of Tasmania has been insufficient time for susceptible grey zone alleles to evolve into the larger expansions.
Autosomal dominant B‐cell immunodeficiency, distal limb anomalies and urogenital malformations (BILU syndrome) – report of a second family
Authors: Tischkowitz M , Goodman F , Koliou M , Webster D , Edery P , Jones A , Wilson LC
Published: December 2004

A family with an unusual combination of B‐cell immunodeficiency, distal limb abnormalities, genitourinary malformations, and mild dysmorphic features has recently been described. Here, we report a second family with similar features, which also shows autosomal dominant inheritance. In affected individuals from both families, sequence analysis of candidate gene HOXA13 did not identify a mutation, and there was no evidence of a microdeletion involving either HOXA13 or the HOXA cluster as a whole. We further delineate the phenotype of this condition in females and add weight to the observation that this is a true syndromic association.
Mutation screening of USH3 gene (clarin‐1) in Spanish patients with Usher syndrome: low prevalence and phenotypic variability
Authors: Aller E , Jaijo T , Oltra S , Alió J , Galán F , Nájera C , Beneyto M , Millán JM
Published: December 2004

Usher syndrome type III is an autosomal recessive disorder clinically characterized by the association of retinitis pigmentosa (RP), variable presence of vestibular dysfunction and progressive hearing loss, being the progression of the hearing impairment the critical parameter classically used to distinguish this form from Usher syndrome type I and Usher syndrome type II. Usher syndrome type III clinical subtype is the rarest form of Usher syndrome in Spain, accounting only for 6% of all Usher syndrome Spanish cases. The gene responsible for Usher syndrome type III is named clarin‐1 and it is thought to be involved in hair cell and photoreceptor cell synapses. Here, we report a screening for mutations in clarin‐1 gene among our series of Usher syndrome Spanish patients. Clarin‐1 has been found to be responsible for the disease in only two families: the first one is a previously reported family homozygous for Y63X mutation and the second one, described here, is homozygous for C40G. This accounts for 1.7% of Usher syndrome Spanish families. It is noticeable that, whereas C40G family is clinically compatible with Usher syndrome type III due to the progression of the hearing loss, Y63X family could be diagnosed as Usher syndrome type I because the hearing impairment is profound and stable. Thus, we consider that the progression of hearing loss is not the definitive key parameter to distinguish Usher syndrome type III from Usher syndrome type I and Usher syndrome type II.
Small de novo duplication in the repeat region of the TATA‐box‐binding protein gene manifest with a phenotype similar to variant Creutzfeldt‐Jakob disease
Authors: Shatunov A , Fridman EA , Pagan FI , Leib J , Singleton A , Hallett M , Goldfarb LG
Published: December 2004

A 20‐year‐old North American patient developed rapidly progressive cognitive decline and pronounced ataxia, a phenotype compatible with prion disease. No structural changes were found in the PRNP gene, which excludes genetic prion disease, but the patient's PRNP codon 129 Met/Met genotype is known to predispose to variant Creutzfeldt‐Jakob disease (vCJD). Further studies identified an expanded allele with 55 CAG/CAA repeats in the TBP gene. The increase of trinucleotide repeat number in the coding region of the TBP gene has previously been associated with spinocerebellar ataxia type 17 (SCA17). The patient's unaffected parents and siblings show normal‐size TBP alleles with 37–38 repeats. Haplotype and nucleotide sequence analyses clearly indicate that the mutation has occurred de novo on a paternal chromosome by insertion/duplication of a (CAA)(CAG)(CAA)(CAG)15 sequence. This report presents a second fully investigated sporadic case of SCA17 occurring as a result of a DNA rearrangement within the polymorphic TBP trinucleotide repeat region. Our findings suggest that patients suspected of vCJD should undergo testing for SCA17, Huntington's disease and other neurodegener‐ative disorders having phenotypic similarities with vCJD.
Fine mapping of the X‐linked split‐hand/split‐foot malformation (SHFM2) locus to a 5.1‐Mb region on Xq26.3 and analysis of candidate genes
Authors: Faiyaz‐Ul‐Haque M , Zaidi SHE , King LM , Haque S , Patel M , Ahmad M , Siddique T , Ahmad W , Tsui L‐C , Cohn DH
Published: December 2004

Split‐hand/split‐foot malformation (SHFM) is a genetically heterogeneous disorder, with five known loci, that causes a lack of median digital rays, syndactyly, and aplasia or hypoplasia of the phalanges, metacarpals, and metatarsals. In the only known SHFM2 family, affected males and homozygous females exhibit monodactyly or bidactyly of the hands and lobster‐claw feet. This family (1) was revisited to include additional subjects and genealogical data. All 39 affected males and three females fully expressed the SHFM, while 13 carrier females examined exhibited partial expression of SHFM. We narrowed the previously linked 22‐Mb genetic interval on Xq24–q26 (2), by analyzing additional family members and typing additional markers. The results define a 5.1‐Mb region with a new centromeric boundary at DXS1114 and a telomeric boundary at DXS1192. We did not identify mutations in the exons and exon/intron boundaries of 19 candidate genes. These data suggest that the mutation may lie in a regulatory region of one of these candidate genes or in another gene within the SHFM2 region with unclear role in limb development.
Psychiatric and neuropsychological characterization of Pallister‐Hall syndrome
Authors: Azzam A , Lerner DM , Peters KF , Wiggs E , Rosenstein DL , Biesecker LG
Published: December 2004

Pallister‐Hall syndrome (PHS) is a rare, single‐gene, malformation syndrome that includes central polydactyly, hypothalamic hamartoma, bifid epiglottis, endocrine dysfunction, and other anomalies. The syndrome has variable clinical manifestations and is inherited in an autosomal dominant pattern. We sought to determine whether psychiatric disorders and/or neuropsychological impairment were characteristic of PHS. We prospectively conducted systematic neuropsychiatric evaluations with 19 PHS subjects ranging in age from 7 to 75 years. The evaluation included detailed clinical interviews, clinician‐rated and self‐report instruments, and a battery of neuropsychological tests. Seven of 14 adult PHS subjects met diagnostic criteria for at least one DSM‐IV Axis I disorder. Three additional subjects demonstrated developmental delays and/or neuropsychological deficits on formal neuropsychological testing. However, we found no characteristic psychiatric phenotype associated with PHS, and the frequency of each of the diagnoses observed in these subjects was not different from that expected in this size sample. The overall frequency of psychiatric findings among all patients with PHS cannot be compared to point prevalence estimates of psychiatric disease in the general population because of biased ascertainment. This limitation is inherent to the study of behavioral phenotypes in rare disorders. The general issue of psychiatric evaluation of rare genetic syndromes is discussed in light of this negative result.
End‐stage renal failure and cardiac mortality after heart transplantation
Authors: Sénéchal Mario , Dorent Richard , Montcel Sophie Tézénas du , Ghossoub Jean‐Jacques , Pavie Alain , Petitclerc Thierry , Dubois Michelle , Isnard Richard , Gandjbakhch Iradj
Published: December 2004

Abstract: Background: Coronary artery disease (CAD) is the leading cause of mortality after the first year of heart transplantation. End‐stage renal failure (ESRF) is more frequent because of long‐term survival. Impact of ESRF on cardiac mortality in heart transplant patients is unappreciated. The hypothesis of accelerated CAD in uremic patients has been suggested.

Methods: In Pitié La Salpêtrière hospital, 1211 heart transplants have been performed between 1982 and 2001. Thirty‐three patients have reached ESRF. A case–control study was performed to identify risk factors responsible for ESRF and to appreciate the impact of ESRF on cardiac mortality.

Results: In cases at 6 months, serum creatinine tended to be higher (159 ± 31 μmol/L vs. 141 ± 44 μmol/L, p = 0.06) and cyclosporine (CSA) dosage (mg/kg) was significantly lower (5.4 ± 1.8 mg/kg vs. 7.7 ± 2.7 mg/kg, p = 0.002). Mean triglyceride level after transplantation until dialysis was significantly lower in cases (2.18 ± 0.82 mmol/L vs. 1.48 ± 0.62 mmol/L, p = 0.002). In cases and controls, cardiac mortality was responsible for 67% (10 of 15) and 38% (three of eight) of all deaths, respectively. High triglyceride level (2 mmol/L) was associated with cardiac mortality [p < 0.03, hazard ratio (HR) = 3.89]. Kaplan–Meier cardiac free survival rates were significantly lower in cases than in controls (p < 0.03).

Conclusion: These data suggest that CSA nephrotoxicity could result from individually determined susceptibility and that hypertriglyceridemia may have a negative impact on renal function and cardiac mortality. The risk of cardiac mortality is increased in heart transplant patients with ESRF. The hypothesis of accelerated atherosclerosis in ESRF patients after heart transplantation leading to higher cardiac mortality incidence needs further study.
Observations regarding the use of sirolimus and tacrolimus in high‐risk cadaveric renal transplantation
Authors: Lo Agnes , Egidi Maria Francesca , Gaber Lillian W , Hosein Shokouh‐Amiri M , Nazakatgoo Nosratollah , Fisher Jonathan S , Osama Gaber A
Published: December 2004

Abstract:  Background:  Balancing the risk of acute rejection (AR) with drug‐induced toxicities complicates the selection of the optimal immunosuppressive regimen, especially in the high‐risk renal transplant recipient. This study was designed to determine the optimal dosage combinations of tacrolimus and sirolimus in a high‐risk cadaveric renal transplant population.

Methods:  Primary cadaveric renal transplant recipients were randomly assigned to receive either standard tacrolimus (trough levels of 10–15 ng/mL) plus reduced sirolimus (trough levels of 5–10 ng/mL) (Group I) or to receive reduced tacrolimus (trough levels of 5–10 ng/mL) plus standard sirolimus (trough levels of 10–15 ng/mL) (Group II). All patients received Thymoglobulin induction and steroids.

Results: Thirty‐nine (16 in Group I and 23 in Group II) high‐risk renal transplant recipients (100% cadaveric donors, 79% African‐American recipients, and 59% delayed graft function) are the subjects of this report. At 6 months, the patient survival rate was 94 and 100% and the graft survival rate was 94 and 83% in Groups I and II, respectively. The incidence of biopsy‐proven AR was 6 and 5% in Groups I and II, respectively. Eight patients (50%) in Group I required discontinuation of tacrolimus, seven because of biopsy‐proven tacrolimus nephrotoxicity and one secondarily to interstitial pneumonitis. Wound complications were the most frequent adverse event reported in both groups.

Conclusions:  The combination of tacrolimus and sirolimus was associated with a low risk of AR in this cohort of high‐risk renal transplant recipients. However, 50% of patients who received standard tacrolimus and reduced sirolimus combination had to be discontinued from the regimen because of biopsy‐proven nephrotoxicity. These preliminary results provide evidence that sirolimus should not be added to tacrolimus without dosage adjustments. We have discontinued recruitment of patients to the standard tacrolimus and reduced sirolimus combination and we have tightened our criteria for selection of marginal donor kidneys with our high‐risk renal transplant recipients.
Eversion thromboendovenectomy in organized portal vein thrombosis during liver transplantation
Authors: Robles Ricardo , Fernández Juan Ángel , Hernández Quiteria , Marín Caridad , Ramírez Pablo , Bueno Francisco Sánchez , Luján Juan Antonio , Rodríguez José Manuel , Acosta Francisco , Parrilla Pascual
Published: December 2004

Portal thrombosis is no longer considered a contraindication for transplantation because of the technical experience acquired in the field of liver transplantation and the development of various surgical techniques. All the same, the results obtained in portal thrombosis patients are at times suboptimal, and the surgical technique used (thromboendovenectomy or veno‐venous bypass) is also controversial.

Between May 1988 and December 2001, 455 liver transplants were performed, of which 32 (7%) presented portal vein thrombosis. Of these, eight belonged to the first 227 transplants (group I), and 24 to the other 228 (group II). Of the 32 cases with portal thrombosis, 20 (62%) were type Ib, seven (22%) type II/III and five (16%) type IV. Twenty‐two were males (69%), with a mean age of 50 yr (range: 30–70 yr); the thrombosis in all cases developed over a cirrhotic liver: 15 cases of an ethanolic origin, 11 because of hepatitis C virus, two cases of autoimmune aetiology, one case of primary biliary cirrhosis, one case because of hepatitis B virus and two cases of a cryptogenic origin. Five cases had a history of surgical treatment for portal hypertension. The surgical method in all cases consisted of an eversion thromboendovenectomy (ETEV) under direct visual guidance, with occlusion of the portal flow using a Fogarty balloon. Once re‐canalization was achieved, we performed local heparinization and end‐to‐end portal anastomosis. In no case was systemic post‐operative heparinization performed.

In the 32 cases in which thrombectomy was attempted it was achieved in 31 of them (96%), failing only in a case of type IV thrombosis, which was resolved by portal arterialization. Of the 31 successful cases, only one with type IV thrombosis re‐thrombosed. The 5‐yr survival rate of the patients in the series was 69%, with 10 patients dying, of whom only two from causes related to the thrombosis and the thrombosis treatment, both with type IV thrombosis.

The ideal treatment for portal thrombosis during liver transplantation is controversial and depends on its extension and the experience of the surgeon. In our experience, ETEV resolves most thromboses (types I, II and III), but management of type IV, which occasionally can be treated with this technique, may require more complex procedures such as bypass, portal arterialization or cavoportal haemitransposition.
Identification of Spinach Farnesyl Protein Transferase
Authors: Parmryd Ingela , Shipton Catherine A. , Swiezewska Ewa , Andersson Bertil , Dallner Gustav
Published: December 2004

Spinach seedlings were found to contain farnesyl protein transferase. The enzyme is activated by Zn2+, but not by Mg2+. The pH optimum is approximately 7.0 and maximal activity is obtained at 40–45°C. The apparent Km for the farnesyl diphosphate substrate is 7 μM, Western blotting of soluble proteins with an antiserum raised against mammalian farnesyl protein transferase demonstrated a specific cross‐reactivity with the spinach enzyme. The antiserum preferentially recognises the β‐subunit of the heterodimeric farnesyl protein transferase, and the corresponding spinach polypeptide has a molecular mass of 42 kDa on SDS/PAGE. The enzyme can employ dithiothreitol as an acceptor for the farnesyl moiety and catalyses the formation of a thioether linkage between these substrates. On the basis of this discovery, a new method was developed utilising the hydrophobicity of the reaction product, and its interaction with poly(propylene). During in vivo labelling, the plants took up dithiothreitol, which inhibited the incorporation of [3H]mevalonate metabolites into proteins, indicating that dithiothreitol might be isoprenylated in vivo as well as in vitro. However, isoprenylation of some proteins remains unaffected by dithiothreitol suggesting the existence of different isoprenylation mechanisms. Thus, it is demonstrated that plants possess farnesyl protein transferase, which resembles its mammalian and yeast homologues.
Osmo‐Expression and Fast Two‐Step Purification of Escherichia Coli Translation Termination Factor RF‐3
Authors: Mortensen Kim Kusk , Hansen Hans Frede , Grentzmann Guido , Buckingham Richard H. , Sperling‐Petersen Hans Uffe
Published: December 2004

The gene for the translation termination factor RF‐3 in Escherichia coli has recently been cloned and sequenced. Only small amounts of the protein have been purified until now, not sufficient for detailed investigation of the structure and function of this factor. For such studies, we have developed an overexpression system and a purification procedure suitable for large quantities of RF‐3. The gene prfC was cloned into the osmo‐inducible plasmid pOSEX3 and subsequently transformed into the E. coli strain MKH13. The expression of prfC in this plasmid, which is under the control of the osmotic pressure in the growth medium, leads to a level of RF‐3 more than 100‐times higher than that in wild‐type cells. Using a new two‐step FPLC protein purification procedure consisting of ion‐exchange chromatography on Q‐Sepharose FF and S‐Sepharose HP, we obtain 220 mg pure RF‐3 from 10 g overproducing cells, corresponding to 55 mg RF‐3/1 medium. The identity of the purified protein was confirmed by matrix‐assisted laser desorption/ionisation mass spectrometry of tryptolytic fragments and by N‐terminal amino acid sequencing. The activity of the purified factor was tested in vitro by measuring the stimulation of RF‐2 dependent formylmethionine release from a ribosomal termination complex and the binding capacity of GTP and GDP. All assays showed that the purified RF‐3 was highly active with a specific activity of approximately 2000 units/mg.
Kinetic Studies of a Soluble αβ Complex of Nitrate Reductase A from Escherichia Coli
Authors: Buc Jean , Santini Claire‐Lise , Blasco Francis , Giordani Roger , Cárdenas María Luz , Chippaux Marc , Cornish‐Bowden Athel , Giordano Gérard
Published: December 2004

A soluble αβ complex of nitrate reductase can be obtained from a strain of Escherichia coli that lacks the narI gene and expresses only the α and β subunits. The β subunit contains four Fe‐S centres and the α subunit contains the molybdenum cofactor, which is the site at which nitrate is reduced. Despite the lack of the γ subunit of the complete enzyme, this complex can still catalyse the reduction of nitrate with artificial electron donors such as benzyl viologen, so that it is suitable for studying the transfer of electrons between these two types of redox centre.

To examine whether the electrons from reduced benzyl viologen are initially delivered to the Fe‐S centres, or directly to the molybdenum cofactor, or both, we have studied the steady‐state kinetics and the binding of benzyl viologen to the αβ complex and mutants αβ* with altered β subunits.

Reduction of the enzyme by reduced benzyl viologen in the absence of nitrate showed that all four Fe‐S centres and the molybdenum cofactor could be reduced. Two classes of site with different equilibrium constants could be distinguished.

The kinetic results suggest that benzyl viologen supplies its electrons directly to the molybdenum cofactor, at a rate showing a hyperbolic dependence on the square of the concentration of the electron donor. A reaction mechanism is proposed for the reduction of nitrate catalysed by the αβ complex of nitrate reductase with artificial electron donors.
Amino Acid Residues 721–729 are Required for Full Factor VIII Activity
Authors: Kjalke Marianne , Heding Anders , Talbo Gert , Persson Egon , Thomsen Johannes , Ezban Mirella
Published: December 2004

Recombinant two‐chain factor VIII, from which the B domain had been deleted, was expressed in Chinese hamster ovary cells. In addition to the major product, three minor factor VIII forms were isolated. The A2 domains generated by thrombin cleavage showed different electrophoretic mobilities. Peptide mapping of the A2 domains showed that two of the factor VIII forms had the expected C‐terminus of the heavy chain at Arg740 [FVIII‐(1–740)] and that the other factor VIII forms had C‐termini at Tyr729 [FVIII‐(1–729)] or Glu720 [FVIII‐(1–720)]. The major FVIII‐(1–740) form, FVIII‐(1–729) and FVIII‐(1–720) contained sulfated tyrosine residues at Tyr718, Tyr719 and Tyr723. The minor FVIII‐(1–740) form was shown to lack sulfation at these positions. The specific clotting activity was approximately 1×104 U/mg for FVIII‐(1–740) (both forms) and FVIII‐(1–729), but twofold lower for FVIII‐(1–720). A time study of thrombin activation showed that FVIII‐(1–720) was activated slower than FVIII‐(1–740), FVIII‐(1–729) and plasma‐derived factor VIII. Partially sulfated FVIII‐(1–740) was activated at the same rate as the fully sulfated FVIII‐(1–740). The equilibrium dissociation constant for binding of factor VIII to inactivated immobilized thrombin was the same for all factor VIII forms, showing that the slower activation of FVIII‐(1–720) was not due to a lower affinity for the anion‐binding exosite in thrombin.