bluuebunny/crossref_metadata_2025 huggingface dataset:
A scanning electron microscope study of plaque accumulation on silk and PVDF suture materials in oral mucosa
Authors: Parirokh M. , Asgary S. , Eghbal M. J. , Stowe S. , Kakoei S.
Published: October 2004

Aim  To examine plaque accumulation on silk and polyvinylidene fluoride (PVDF) sutures at different time intervals.

Methodology  Twenty‐one male albino rabbits received sutures under general and local anaesthesia. After 3, 5 and 7 days sutures were removed and processed for scanning electron microscope (SEM) observation. The Friedman and the Wilcoxon tests were used to compare contamination on PVDF and silk suture materials at different time intervals.

Results  At all time intervals, the whole surface of silk sutures was covered with a thick layer of bacterial plaque and debris. Microorganisms and blood cells on the surface and between the filaments of the silk suture material were observed. Light debris appeared around the knot area of PVDF sutures after 3 days. At 5 and 7 days, contamination could be seen in scattered areas along the suture material. The average contaminated area was smaller on PVDF suture materials, which were removed at 5 than at 7 days after insertion. At 3 days, PVDF sutures showed significantly less contamination than at 5 and 7 days (P = 0.002). There were statistically significant differences between silk and PVDF sutures at 3, 5 and 7 days.

Conclusion  SEM observation showed that PVDF sutures were contaminated less than silk sutures at 3, 5 and 7 days.
The annual frequency of root fillings, tooth extractions and pulp‐related procedures in Danish adults during 1977–2003
Authors: Bjørndal L. , Reit C.
Published: October 2004

Aim  To investigate a hypothesized long‐time decrease of endodontic treatment in a population with low caries prevalence.

Methodology  A Danish nationwide database including almost all dental diagnostic, prophylactic and therapeutic procedures performed in Danish adults was available. Data on the annual frequencies of root fillings, extractions, pulpotomies, direct pulp cappings and stepwise excavations between 1977 and 2003 were analysed. Data on pulpal and periapical diagnoses were not available and on patients age and gender only from 1996.

Results  Between 1977 and 2003 the annual number of root filled canals increased from 268 223 to 364 867 (36%). The annual number of root filled teeth increased from 160 119 to 191 803 (20%). During the period, the annually registered patients increased by 16%. Calculated per 1000 patients, the number of root fillings showed a statistically significant increase of 17%. In root filled teeth the canal/tooth ratio increased from 1.67 to 1.96. Root fillings were frequently recorded in all age groups with the bulk of treatments performed on patients between 40 and 60 years of age. At a total population level, the rate of root fillings decreased among younger individuals and increased among older. The annual number of tooth extractions was more than halved from 656 624 in 1977 to 346 490 in 2003. Pulpotomies decreased markedly over the period and less than 10 treatments per 1000 patients were noted for pulp capping as well as stepwise excavation procedures.

Conclusions  The present study failed to show a long‐time decrease of endodontic treatment in a population with low caries prevalence. On the contrary, an increase of root filled canals was observed between 1977 and 2003, which was probably due to a reduction of the tooth extraction rate and an increased treatment of multi‐rooted teeth.
Evolutionary history of coastal tiger beetles in Japan based on a comparative phylogeography of four species
Authors: SATOH A. , SOTA T. , UÉDA T. , ENOKIDO Y. , PAIK J. C. , HORI M.
Published: October 2004

To reveal the phylogeographical patterns of four species of coastal tiger beetles in Japan (Lophyridia angulata, Abroscelis anchoralis, Cicindela lewisii and Chaetodera laetescripta), we conducted phylogenetic and nested clade analysis (NCA) using the mitochondrial DNA sequences of two loci (COI and 16S rRNA), with specimens sampled from Japan and neighbouring countries. Abroscelis anchoralis and L. angulata have similar disjunct distributions in Japan. The NCA indicated past fragmentation involving three isolated areas of A. anchoralis. In contrast, local populations of L. angulata in Japan shared the same haplotype, indicating recent vicariance. Co‐occurrence of haplotypes from several divergent clades in Japanese populations of Ch. laetescripta suggested ancient vicariance and subsequent intermixing of local populations. The tree topology of C. lewisii, with shallow branches and little geographical segregation of haplotypes between Japan and Korea or within Japan, suggested that the Japanese population was segregated from the Korean population only recently. Restricted gene flow, with isolation by distance, was inferred for various geographical associations of haplotypes for coastal tiger beetles in the NCA. Based on these phylogeographical patterns, coupled with a molecular clock approach, the evolutionary history of four species of coastal tiger beetles was deduced, with the additional consideration of the competitive relationships among those species. We also discuss the conservation of highly localized A. anchoralis populations in Japan, using the concept of evolutionarily significant units.
Somatic mutation‐mediated evolution of herbicide resistance in the nonindigenous invasive plant hydrilla (Hydrilla verticillata)
Authors: MICHEL ALBRECHT , ARIAS RENEE S. , SCHEFFLER BRIAN E. , DUKE STEPHEN O. , NETHERLAND MICHAEL , DAYAN FRANCK E.
Published: October 2004

Hydrilla (Hydrilla verticillata L.f. Royle) was introduced to the surface water of Florida in the 1950s and is today one of the most serious aquatic weed problems in the USA. As a result of concerns associated with the applications of pesticides to aquatic systems, fluridone is the only USEPA‐approved chemical that provides systemic control of hydrilla. After a decrease in fluridone's efficacy at controlling hydrilla, 200 Florida water bodies were sampled to determine the extent of the problem and the biological basis for the reduced efficacy. Our studies revealed that hydrilla phenotypes with two‐ to six‐fold higher fluridone resistance were present in 20 water bodies. Since fluridone is an inhibitor of the enzyme phytoene desaturase (PDS), the gene for PDS (pds) was cloned from herbicide‐susceptible and ‐resistant hydrilla plants. We report for the first time in higher plants three independent herbicide‐resistant hydrilla biotypes arising from the selection of somatic mutations at the arginine 304 codon of pds. The three PDS variants had specific activities similar to the wild‐type enzyme but were two to five times less sensitive to fluridone. In vitro activity levels of the enzymes correlated with in vivo resistance of the corresponding biotypes. As hydrilla spread rapidly to lakes across the southern United States in the past, the expansion of resistant biotypes is likely to pose significant environmental challenges in the future.
Recolonization and radiation in Larix (Pinaceae): evidence from nuclear ribosomal DNA paralogues
Authors: WEI XIAO‐XIN , WANG XIAO‐QUAN
Published: October 2004

Gene paralogy frequently causes the conflict between gene tree and species tree, but sometimes the coexistence of a few paralogous copies could provide more markers for tracing the phylogeographical process of some organisms. In the present study, nrDNA ITS paralogues were cloned from all but one species of Larix, an Eocene genus having two sections, Larix and Multiserialis, with a huge circumboreal distribution and an Eastern Asia–Western North America disjunction, respectively. A total of 96 distinct clones, excluding five putative pseudogenes or recombinants, were obtained and used in the gene genealogy analysis. The clones from all Eurasian species of section Larix are mixed together, suggesting that recolonization and recent morphological differentiation could have played important roles in the evolution of this section. In contrast, the species diversification of the Eurasian section Multiserialis may result from radiation in the east Himalayas and its vicinity, considering extensive nrDNA founder effects in this group. Our study also suggests that the distribution pattern analysis of members of multiple gene family would be very useful in tracking the evolutionary history of some taxa with recent origin or rapid radiation that cannot be resolved by other molecular markers.
The genetic structure of adders (Vipera berus) in Fennoscandia: congruence between different kinds of genetic markers
Authors: CARLSSON M. , SÖDERBERG L. , TEGELSTRÖM H.
Published: October 2004

In order to elucidate the colonization history of Fennoscandian adders (Vipera berus), the phylogeographical patterns of two nuclear sets of DNA markers (random amplified polymorphic DNA and microsatellite) are compared with that previously obtained from mitochondrial DNA. An eastern and a western lineage within Fennoscandian adders is readily distinguishable using both sets of nuclear markers, corroborating the hypothesis that the lineages stem from separate glacial refugia. Moreover, the same contact zones as were derived from mitochondrial data are clearly identifiable. Both sets of nuclear markers detect a high level of admixture across one zone in northern Finland, with introgression reaching far west into Sweden.
The molecular phylogenetics of endangerment: cryptic variation and historical phylogeography of the California tiger salamander,Ambystoma californiense
Authors: SHAFFER H. BRADLEY , PAULY GREGORY B. , OLIVER JEFFREY C. , TRENHAM PETER C.
Published: October 2004

A primary goal of conservation genetics is the discovery, delimitation and protection of phylogenetic lineages within sensitive or endangered taxa. Given the importance of lineage protection, a combination of phylogeography, historical geology and molecular clock analyses can provide an important historical context for overall species conservation. We present the results of a range‐wide survey of genetic variation in the California tiger salamander,Ambystoma californiense, as well as a summary of the past several million years of inundation and isolation of the Great Central Valley and surrounding uplands that constitute its limited range. A combination of population genetic and phylogenetic analyses of mitochondrial DNA variation among 696 samples from 84 populations revealed six well‐supported genetic units that are geographically discrete and characterized by nonoverlapping haplotype distributions. Populations from Santa Barbara and Sonoma Counties are particularly well differentiated and geographically isolated from all others. The remaining units in the Southern San Joaquin Valley, Central Coast Range, Central Valley and Bay Area are separated by geological features, ecological zone boundaries, or both. The geological history of the California landscape is consistent with molecular clock evidence suggesting that the Santa Barbara unit has been isolated for at least 0.74–0.92 Myr, and the Sonoma clade is equally ancient. Our work places patterns of genetic differentiation into both temporal‐ and landscape‐level contexts, providing important insights into the conservation genetics of the California tiger salamander.
Bcl‐2 expression inversely correlates with tumour cell differentiation in medulloblastoma
Authors: Schüller U. , Schober F. , Kretzschmar H. A. , Herms J.
Published: October 2004

Medulloblastoma (MB) is a cerebellar primitive neuroectodermal tumour that occurs predominantly in childhood. It can be mainly divided into classical and desmoplastic tumours, but differential diagnosis is often difficult. Patients’ prognosis is poor and neuropathological markers that reliably predict outcome are still missing. In a series of 104 MBs including 80 tumours of the classical and 24 tumours of the desmoplastic variant we studied the number of apoptotic figures and the expression of the proto‐oncogene bcl‐2, an anti‐apoptotic protein known to affect tumour cell proliferation. We observed a strong correlation between the expression of bcl‐2 with patients’ age (P < 0.001) as well as with the desmoplastic subtype (P < 0.001). Here, protein expression was found to be restricted to internodular, less differentiated, highly proliferative areas. In classical MB, bcl‐2 was detected only in 23% of cases and was highly inversely correlated with the expression of synaptophysin (P < 0.001) indicating that bcl‐2 is predominantly expressed by undifferentiated classical MB. With regard to prognosis the expression of bcl‐2 tended to correlate with poor outcome in classical MB but not in desmoplastic MB, although not to a statistically significant extension (P = 0.06). On the other hand, a high number of apoptotic figures in the tumour tissue was found to indicate poor prognosis independent of the histological subtype (P < 0.05).
Expression of glucose transporter 5 by microglia in human gliomas
Authors: Sasaki A. , Yamaguchi H. , Horikoshi Y. , Tanaka G. , Nakazato Y.
Published: October 2004

Our previous studies indicate that glucose transporter 5 (GLUT5) is a microglial marker in routine paraffin sections, and is rarely present in monocytes/macrophages of the peripheral organs. We examined the expression of GLUT5 in 91 cases of human gliomas to characterize the microglial phenotype in glioma tissues. Immunohistochemistry was performed on formalin‐fixed, paraffin‐embedded sections using such antibodies as a GLUT5 antibody, two markers for activated microglia: major histocompatibility complex (MHC) class II Ag and macrophage scavenger receptor class A (MSR‐A), and MIB‐1 antibody. The immunoreactivity of GLUT5 was present in three microglial phenotypes: ramified (resting), activated, and ameboid (macrophagic) microglia in most of the cases. A double‐labelling study of astrocytic tumours using GLUT5 and MIB‐1 antibodies demonstrated a proportion of proliferating microglia. However, no morphological difference between MIB‐1‐positive, microglial cells and MIB‐1‐negative, microglial cells was found. The number of GLUT5‐positive microglia was significantly (P < 0.001) higher in astrocytic tumours than in oligodendroglial tumours. Many GLUT5‐positive microglia (up to 52% in total cells) were often observed in pilocytic astrocytomas, where microglial cells were predominantly ramified, and the number of MHC class II‐ or MSR‐A‐positive microglia was less than GLUT5‐positive microglia. Thus, the present study indicated that intrinsic microglia can be a source of microglia/macrophages cell populations in astrocytic tumours, and that pilocytic astrocytomas often have a high proportion of microglial cells with mild activation.
Imaging of iron oxide nanoparticles by MR and light microscopy in patients with malignant brain tumours
Authors: Neuwelt E. A. , Várallyay P. , Bagó A. G. , Muldoon L. L. , Nesbit G. , Nixon R.
Published: October 2004

Objective:

Ferumoxtran‐10 (Combidex®), a dextran‐coated iron oxide nanoparticle, provides enhancement of intracranial tumours by magnetic resonance (MR) for more than 24 h and can be imaged histologically by iron staining. Our goal was to compare ferumoxtran imaging and histochemistry vs. gadolinium enhancement in malignant brain tumours on preoperative and postoperative MR. Methods: Seven patients with primary and metastatic malignant tumours underwent MR imaging with gadolinium and ferumoxtran both pre‐ and postoperatively. Normalized signal intensities on the ferumoxtran‐enhanced scans were determined in representative regions of interest. Resected tissue from six ferumoxtran patients and from three patients who did not receive ferumoxtran was assessed for localization of iron in tumour and reactive brain. Results: All malignant tumours (all of which enhanced by gadolinium MR) showed ferumoxtran accumulation with T1 and T2 signal changes, even using a 0.15 T intraoperative MR unit in one patient. Iron staining was predominantly in reactive cells (reactive astrocytes and macrophages) and not tumour cells. In five of the seven patients, including two patients who showed additional lesions, areas enhancing with ferumoxtran but not with gadolinium were observed. Comparison of the pre‐ and postoperative MR revealed residual ferumoxtran‐enhancing areas in four of seven cases. Conclusion: In malignant tumours, ferumoxtran may show areas of enhancement, even with a 0.15 T intraoperative MR, that do not enhance with gadolinium. Ferumoxtran‐enhancing lesions have persistent increased T1 signal intensity for 2–5 days, which may provide advantages over gadolinium for postoperative imaging. Histochemistry for iron shows uptake of ferumoxtran in reactive cells (astrocytes and macrophages) rather than tumour cells.
Spinal motoneurone distress during experimental allergic encephalomyelitis
Authors: Giardino L. , Giuliani A. , Fernandez M. , Calzà L.
Published: October 2004

The main pathophysiological feature characterizing multiple sclerosis (MS) is demyelination. However, the possibility of neural damage has recently been proposed as a mechanism in chronic disease. Experimental allergic encephalomyelitis (EAE) is the most widely used experimental model for MS. We investigated occurrences of microglial activation and astrocytosis in the spinal cord, choline acetyl‐transferase (ChAT) and calcitonin gene‐related peptide (CGRP) mRNA regulation in spinal motoneurones during EAE. EAE was induced in female Lewis rats by injecting guinea pig spinal cord tissue in complete Freund's adjuvant (CFA) to which heat‐inactivated Mycobacterium had been added. Rats injected with CFA and uninjected rats were used as controls. ChAT and CGRP mRNAs were studied by in situ hybridization in the lumbar spinal cord and a computerized grain counting procedure was used for quantification. No differences in ChAT mRNA level were found between control and CFA‐injected rats. ChAT mRNA level was strongly reduced in EAE 14 days after immunization and then recovered (29 days after immunization). CGRP mRNA increased 14 days after immunization, and then recovered to control level. Extensive long‐lasting gliosis developed in the spinal cord and around motoneurones and a transient expression of p75LNGFR in motoneurones was also found. These data suggest that during EAE, gliosis induces distress in spinal cord neurones involving the synthesis enzyme for the main transmitter.
No evidence for mutations or altered expression of the Suppressor of Fused gene (SUFU) in primitive neuroectodermal tumours
Authors: Koch A. , Waha A. , Hartmann W. , Milde U. , Goodyer C. G. , Sörensen N. , Berthold F. , Digon‐Söntgerath B. , Krätzschmar J. , Wiestler O. D. , Pietsch T.
Published: October 2004

The sonic hedgehog (Shh) and the Wnt signalling pathways are involved in the development of medulloblastomas (MBs), the most frequent malignant brain tumours in children. Components of these two developmental and cancer‐associated pathways, including (Patched) PTCH, SMOH, adenomatous polyposis coli (APC), β‐catenin and AXIN1 show somatic mutations in sporadic MBs. In this study we analysed SUFU (human suppressor of fused), which acts as a negative regulator of both the Shh and Wnt signalling pathways and therefore represents a putative tumour suppressor gene, to find out if it is also involved in the pathogenesis of sporadic MBs. We screened 145 primitive neuroectodermal tumours (PNETs) including 90 classic MBs, 42 of the desmoplastic variant and two medullomyoblastomas as well as 11 MB cell lines for mutations using single‐strand conformational polymorphism (SSCP) and sequencing analysis. 18% of the MBs exhibited allelic losses on chromosome 10q. In contrast to a previous report, in which truncating mutations of SUFU have been identified in 9% of MBs, we were not able to identify somatic mutations of SUFU in our large tumour panel. We uncovered single nucleotide polymorphisms (SNPs) in exon 4, 8, 11 and in intron 2 in the SUFU gene. Expression analysis by competitive reverse transciption‐polymerase chain reaction (RT‐PCR) revealed no difference in SUFU mRNA levels of both MB subtypes and normal foetal or adult cerebellar tissues. Our results indicate that genetic alterations of the SUFU gene, do not contribute significantly to the molecular pathogenesis of MBs.
Absence of neuronal nitric oxide synthase (nNOS) as a pathological marker for the diagnosis of Becker muscular dystrophy with rod domain deletions
Authors: Torelli S. , Brown S. C. , Jimenez‐Mallebrera C. , Feng L. , Muntoni F. , Sewry C. A.
Published: October 2004

Immunohistochemistry using antibodies to dystrophin is the pathological basis for the diagnosis of Duchenne and Becker muscular dystrophy (DMD and BMD). While the sarcolemma of DMD muscle is negative, BMD muscle generally shows variable labelling because of the translation of a partially functional dystrophin that is localized to the sarcolemma. In rare cases, however, this labelling is equivocal and similar to that observed in controls making diagnosis difficult. We report here that in such instances immunolabelling with antibodies to the neuronal form of nitric oxide synthase (nNOS) can be useful in suspecting a dystrophinopathy with a mutation in the ‘hot‐spot’ rod domain and help to direct molecular analysis. nNOS localizes to the sarcolemma of mature muscle fibres via several components of the dystrophin‐associated protein complex (DAPC) including dystrophin but sarcolemmal nNOS is lost when dystrophin levels are very low or absent because of deletions in critical regions of the rod domain. We report three cases who presented with only mild or no muscle weakness but had elevated serum creatine kinase activity and dystrophin immunolabelling indistinguishable from normal, making a pathological diagnosis difficult. All three cases had a complete absence of sarcolemmal nNOS and were subsequently found to have an in‐frame deletion in the common rod domain exons (in these cases 48, 45–51, 47–53) compatible with a BMD. In addition, we observed that nNOS appears to be developmentally regulated with the antibody used and was often absent from the sarcolemma of immature fibres. These findings demonstrate the value of including antibodies to nNOS in routine immunohistochemical studies and that absence of nNOS can be a more sensitive marker than up‐regulation of utrophin for diagnosis of BMD. Immaturity of fibres, however, needs to be taken into account, especially in neonates.
Ezrin expression in tissue microarray of primary and recurrent gliomas
Authors: Tynninen O. , Carpén O. , Jääskeläinen J. , Paavonen T. , Paetau A.
Published: October 2004

Malignant progression, infiltrative growth pattern and recurrencies after surgery are characteristic features of diffuse gliomas. Ezrin is a membrane‐cytoskeleton linker protein expressed in several types of neoplasms. In experimental models, increased ezrin expression correlates with invasion of malignant glioma cells. We studied ezrin expression and its correlation with patient survival in 229 primary and recurrent astrocytomas (WHO grades II–IV), oligodendrogliomas (II–III) and oligoastrocytomas (II–III) of 113 patients. Ezrin expression as evaluated by immunohistochemistry and immunoblotting was detected in all studied glioma types. Staining intensity and number of immunoreactive cells correlated with increasing malignancy of astrocytomas and oligoastrocytomas (P = 0.001). Ezrin expression was strongest in astrocytomas (P = 0.006). Also oligodendrogliomas were positive for ezrin. High ezrin expression in primary gliomas correlated with shorter time to recurrence (P < 0.05) and poor overall survival (P < 0.05) of the patients. Ezrin expression increased during progression of the tumours (P < 0.05). However, ezrin was not an independent prognostic factor. The results of this study show that ezrin expression is associated with progression of gliomas and correlates with histological cell type and WHO tumour grade.
HIV‐1 expression protects macrophages and microglia from apoptotic death
Authors: Cosenza M. A. , Zhao M.‐L. , Lee S. C.
Published: October 2004

Macrophages and microglia are the predominant cells infected with HIV‐1 in the brain, yet the effects of productive HIV infection on the fate of these cells are poorly understood. In this study, we tested the hypothesis that HIV‐1 expression influences cell death in infected macrophages and microglial cells. We detected apoptosis by terminal deoxynucleotidyl transferase‐mediated dUTP nick end labelling (TUNEL) in the cerebral white matter of control and HIV encephalitis (HIVE) brains, and quantitatively analysed apoptotic cells with respect to their location (vessel‐associated vs. parenchymal), CD68 expression, and HIV‐1 p24 expression. There were more vessel‐associated, but not more parenchymal, TUNEL+ cells in HIVE cases as compared to controls. Vessel‐associated TUNEL+ cells were primarily endothelial cells (von Willebrand factor+) or macrophages (CD68+). TUNEL+/CD68+ cells were present in both control and HIVE cases in similar frequencies (2.1 ± 0.7% vs. 1.9 ± 0.7% of total CD68+ populations, respectively). In HIVE, TUNEL+/p24+ cells were 0.4 ± 0.2% of the total p24+ cell population, which was lower than the frequency of TUNEL+/CD68+ cells (1.9 ± 0.7%) in the total CD68+ macrophage population. These results suggest that HIV‐1‐infected macrophages and microglia are resistant to apoptosis, and may contribute to the formation of a central nervous system viral reservoir.
A quantitative investigation of neuronal cytoplasmic and intranuclear inclusions in the pontine and inferior olivary nuclei in multiple system atrophy
Authors: Nishie M. , Mori F. , Yoshimoto M. , Takahashi H. , Wakabayashi K.
Published: October 2004

Multiple system atrophy (MSA) is a sporadic neurodegenerative disease characterized by the presence of neuronal and oligodendroglial α‐synuclein aggregates. To investigate the relationship between the occurrence of neuronal cytoplasmic and intranuclear inclusions (NCIs and NNIs, respectively) and the progression of neuronal degeneration, we performed a quantitative analysis of the pontine and inferior olivary nuclei based on 14 cases of MSA. α‐Synuclein immunohistochemistry revealed that NCIs and NNIs were present in both brain nuclei in all the cases. The average incidence of NCIs in the pontine and inferior olivary nuclei was 9.1% and 25.8%, respectively, and that of NNIs was 9.2% and 9.0%, respectively. The number of NNIs was strongly correlated with that of neurones in the pontine and inferior olivary nuclei. Although the number of NCIs was not correlated with the neuronal population in both nuclei, the NCI count in patients with moderate MSA was higher than in patients with mild MSA. The NNI count was much higher than the NCI count in the pontine nucleus in four patients, and was the same in the olivary nucleus in three of the four patients. Moreover, the neuronal population in the NNI‐predominant cases was significantly higher than in the NCI‐predominant cases. These findings suggest that NCI formation is accelerated by the progression of the disease process, and that in MSA, NNI formation is an earlier phenomenon than NCI formation.
Identification of up‐regulated genes by array analysis in scrapie‐infected mouse brains
Authors: Brown A. R. , Webb J. , Rebus S. , Williams A. , Fazakerley J. K.
Published: October 2004

The major neuropathological features of the transmissible spongiform encephalopathies (TSEs) are well documented, however, the underlying molecular events are poorly defined. We have applied cDNA expression arrays and quantitative RT‐PCR to the study of gene expression in the brain, and more specifically in the hippocampus, of the well‐characterized ME7/CV mouse model of scrapie. The number of genes showing consistent, scrapie‐associated changes in expression was limited, and was primarily restricted to glial‐associated genes. Increased expression of genes encoding glial fibrillary acidic protein, vimentin, complement component 1q (alpha and beta polypeptides), cathepsin D, clusterin and cystatin C was evident in the hippocampus from 170 days after inoculation (dpi), with expression increasing thereafter to terminal disease (225–235 dpi). Elevation of gene expression preceded clinical disease by approximately 30 days, and coincided with a 20‐day period in the ME7/CV model during which 50% of the CA1 hippocampal neurones are lost. Increased expression of cystatin C, an inhibitor of lysosomal cysteine proteases, is a novel finding in the context of TSE neuropathology and was confirmed by Western analysis and immunocytochemistry.
Expression of stress‐activated kinases c‐Jun N‐terminal kinase (SAPK/JNK‐P) and p38 kinase (p38‐P), and tau hyperphosphorylation in neurites surrounding βA plaques in APP Tg2576 mice
Authors: Puig B. , Gómez‐Isla T. , Ribé E. , Cuadrado M. , Torrejón‐Escribano B. , Dalfó E. , Ferrer I.
Published: October 2004

Hyperphosphorylated tau in neurites surrounding β‐amyloid (βA) deposits, as revealed with phospho‐specific anti‐tau antibodies, are found in amyloid precursor protein (APP) Tg2576 mice. Because βA is a source of oxidative stress and may be toxic for cultured cells, the present study examines the expression of phosphorylated (active) stress‐activated kinase c‐Jun N‐terminal kinase (SAPK/JNK‐P) and p38 kinase (p38‐P), which have the capacity to phosphorylate tau at specific sites, and their specific substrates c‐Jun and ATF‐2, which are involved in cell death and survival in several paradigms, in Tg2576 mice. The study was planned to shed light about the involvement of these kinases in tau phosphorylation in cell processes surrounding amyloid plaques, as well as in the possible phosphorylation (activation) of c‐Jun and activating transcription factor‐2 (ATF‐2) in relation to βA deposition. Moderate increase in the expression of phosphorylated mitogen‐activated protein kinase and extracelullar signal‐regulated kinase (MAPK/ERK‐P) occurs in a few amyloid plaques. However, strong expression of SAPK/JNK‐P and p38‐P is found in the majority of, if not all, amyloid plaques, as seen in serial consecutive sections stained for βA and stress kinases. Moreover, confocal microscopy reveals colocalization of phospho‐tau and SAPK/JNK‐P, and phospho‐tau and p38‐P in many dystrophic neurites surrounding amyloid plaques. Increased expression levels of nonbound tau, SAPK/JNK‐P and p38‐P are corroborated by Western blots of total cortical homogenate supernatants in Tg2576 mice when compared with age‐matched controls. No increase in phosphorylated c‐JunSer63 (c‐Jun‐P) and ATF‐2Thr71 (ATF‐2‐P) is found in association with βA deposits. In addition, no expression of active (cleaved) caspase‐3 (17 kDa) has been found in transgenic mice. Taken together, these observations provide a link between βA‐induced oxidative stress, activation of stress kinases SAPK/JNK and p38, and tau hyperphosphorylation in neurites surrounding amyloid plaques, but activation of these kinases is not associated with accumulation of c‐Jun‐P and ATF‐2‐P, nor with activation of active caspase‐3 in the vicinity of βA deposits.
Differential patterns of insulin‐like growth factor‐I and ‐II mRNA expression in medulloblastoma
Authors: Van Doorn J. , Gilhuis H. J. , Koster J. G. , Wesseling P. , Reddingius R. E. , Gresnigt M. G. , Bloemen R. J. , Van Muijen G. N. P. , Van Buul‐Offers S. C.
Published: October 2004

Insulin‐like growth factors (IGFs) play an important role in tumour growth and development. We hypothesized that this is also the case for medulloblastomas, which are highly malignant cerebellar brain tumours usually occurring in children. In these tumours the expression patterns of IGF‐I and ‐II mRNA were studied. Tumour specimens obtained from 12 children and two adults at diagnosis were hybridized in situ with digoxigenin‐labelled cRNA probes for hIGF‐I and hIGF‐II mRNAs. In all cases, tumour cells showed abundant expression of IGF‐I mRNA. Nine of the 14 tumours showed variable but significant IGF‐II expression. In these tumours, the hybridization signal almost exclusively colocalized with a subpopulation of Ki‐M1P positive cells that were identified as ramified microglia (RM) cells. In the five tumours without IGF‐II expression, microglia/brain macrophages with a more rounded amoeboid‐like morphology predominated. RM cells in normal cerebellar tissues, residing abundantly in areas of the white and, to a less extent, in the grey matter, were IGF‐II mRNA‐negative. These RM cells showed a thinner and more extensively branched appearance and were more evenly distributed than those encountered in medulloblastoma. Probably, during the transformation from the resting ramified towards the amoeboid morphology (or vice versa) IGF‐II mRNA expression is only temporarily induced. The physiological meaning of the induction of IGF‐II mRNA expression by these cells in medulloblastoma remains unclear but any IGF‐II peptide synthesized could exert unfavourable mitogenic and antiapoptotic effects on adjacent tumour cells. However, in this relatively small number of cases we could not find any indications for a relationship between clinical characteristics of the various cases and the extent of IGF‐II mRNA expression.
Vascular endothelial growth factor and the nervous system
Authors: Brockington A. , Lewis C. , Wharton S. , Shaw P. J.
Published: October 2004

Vascular endothelial growth factor (VEGF) is an angiogenic factor essential for the formation of new blood vessels during embryogenesis and in many pathological conditions. A new role for VEGF as a neurotrophic factor has recently emerged. In the developing nervous system, VEGF plays a pivotal role not only in vascularization, but also in neuronal proliferation, and the growth of coordinated vascular and neuronal networks. After injury to the nervous system, activation of VEGF and its receptors may restore blood supply and promote neuronal survival and repair. There is a growing body of evidence that VEGF is essential for motor neurone survival, and that aberrant regulation of VEGF may play a role in the degeneration of neurones in diseases such as amyotrophic lateral sclerosis.
Progress in searching for susceptibility loci and genes for smoking‐related behaviour
Authors: Li MD , Ma JZ , Beuten J
Published: October 2004

Smoking behaviour is influenced by both genetic and environmental factors. Many years of twin and adoption studies have demonstrated that heritability is at least 50% responsible for both smoking initiation and smoking persistence. Furthermore, the extent, to which genetic and environmental factors contribute to smoking behaviour, is significantly different in men and women. Linkage analyses from several independent studies provide evidences for suggested linkage of smoking behaviour to chromosomes 1, 2, 4, 5, 6, 9, 10, 11, 14, 17, 18 and 21. However, almost none of these loci have been replicated yet. Furthermore, numerous population‐based association studies have been performed to examine the effects of a number of candidate genes, such as cytochrome P450, dopamine receptor (DR) and transporter, serotonin transporter and nicotinic acetylcholine receptor, on smoking behaviour. However, many of these reports have not yet received independent confirmation. Of these candidate genes, the D2 dopamine receptor (DRD2) gene has been extensively studied. Meta‐analysis of 12 reported studies showed a significantly higher prevalence of the DRD2 TaqI A1 allele in smokers than that in non‐smokers (p < 0.0001; pooled OR = 1.50; 95% CI = 1.33–1.70). For other candidate genes, insufficient published studies are available to allow a meta‐analysis to be performed, or meta‐analysis showed no significant difference between smokers and non‐smokers. More studies are necessary to determine whether these genes play a significant role in smoking behaviour.
Attitudes and beliefs concerning prostate cancer genetic screening
Authors: Doukas David J. , Localio A. Russell , Li Yuelin
Published: October 2004

This quantitative study determines the values, beliefs, and attitudes influencing the intention of men to undergo or defer genetic testing for prostate cancer risk using a model based on components of the Theory of Reasoned Action and Health Belief Model. Telephone interviews of a community sample of 400 men in a large, East Coast metropolitan area of diverse educational, ethnic, and age backgrounds were conducted to rank key values and beliefs about genetic testing for prostate cancer risk in anticipation of its future availability. Descriptive statistics, univariate analyses, and logistic regression were used in data analysis. The factors of values attached to consequences, motivation from self, beliefs in benefits, and a motivation to comply with others (borderline) were statistically significant for testing intention. Of all demographics, only increased education was associated with diminished interest in testing. Desire to be tested varied widely across groups of men. Based on these identified values, health professionals can better understand men's values and beliefs on the risks and benefits of testing. The relationship of men to others, family and society, require further investigation in this and other aspects of genetic testing.
Hutchinson–Gilford progeria syndrome
Authors: Pollex RL , Hegele RA
Published: October 2004

Hutchinson–Gilford progeria syndrome (HGPS) is an extremely rare genetic disorder that causes premature, rapid aging shortly after birth. Recently, de novo point mutations in the Lmna gene have been found in individuals with HGPS. Lmna encodes lamin A and C, the A‐type lamins, which are an important structural component of the nuclear envelope. The most common HGPS mutation is located at codon 608 (G608G). This mutation creates a cryptic splice site within exon 11, which deletes a proteolytic cleavage site within the expressed mutant lamin A. Incomplete processing of prelamin A results in nuclear lamina abnormalities that can be observed in immunofluorescent studies of HGPS cells. Mouse models, such as Lmna knockout, Zmpste24 knockout, and Lmna L530P knockin will help the study of progeria. Lmna mutations have also recently been found in patients with atypical forms of progeria. The discovery of the HGPS mutations brings the total number of diseases caused by mutant Lmna to nine, underscoring the astonishing spectrum of laminopathies. Future research into HGPS could also provide important clues about the general process of aging and aging‐related diseases.
Haplotypic analyses of the aldosterone synthase gene CYP11B2 associated with stage‐2 hypertension in northern Han Chinese
Authors: Gu D , Ge D , He J , Li B , Chen J , Liu D , Chen J , Chen R
Published: October 2004

The objective of this study was to investigate the association of polymorphisms in the aldosterone synthase gene CYP11B2 (−344T/C, Lys173/Arg, and an intronic conversion [IC]) with stage‐2 hypertension in northern Han Chinese. A total of 503 hypertensives and their age‐, gender‐, and area‐matched controls were included in this study. The female hypertensives had significantly higher frequencies of the −344T, 173Lys, and IC‐conversion alleles (p = 0.002, 0.002, and 0.014, respectively). The estimated frequency of haplotype composed of the −344T, 173Lys, and IC‐conversion alleles (haplotype 4) was significantly higher in the female hypertensives compared with their controls (p = 0.007). Using a multivariate score test, we found that haplotype 4 remained associated with female hypertension after the adjustment for covariates (p = 0.003), while the haplotype 3 of T‐Arg‐WT showed a protective effect both in the males and in the females (p = 0.03 and 0.006, respectively). The odds ratio for haplotype phase of 4–4 was 2.60 (95% CI, 1.21–5.58) and for 3–3, 0.20 (95%CI, 0.03–0.77). These results indicate that the Lys173 and the IC‐conversion allele of the CYP11B2 gene confer an increased risk for stage‐2 hypertension in northern Han Chinese women.
Anticipated reactions to genetic testing for hereditary non‐polyposis colorectal cancer susceptibility*
Authors: Brodersen NH , Sutton S , Goff S , Hodgson SV , Thomas HJW
Published: October 2004

Genetic testing for cancer susceptibility (e.g. hereditary non‐polyposis colorectal cancer) is available for some families with a history of colon cancer. Our aim was to investigate participants' anticipated emotional and behavioral reactions to genetic testing for colon cancer and whether gender or clinical risk influences these reactions. 437 asymptomatic participants with a colorectal cancer family history completed a questionnaire about anticipated emotions and actions, under different genetic testing scenarios. More women than men anticipated feeling worried, regretful, and angry if tested positive. People at lower‐risk anticipated more surprise and disbelief than those at higher‐risk. People anticipated feeling more guilt, regret and less relief if they were not tested than if they were. High‐risk results were anticipated to increase depression and worry. Most people still wanted screening if at low risk, anticipated leading healthier lifestyles whatever the result, but would make more plans for the future if they were at high risk. Clinical implications are that as anticipated emotional effects of not being tested may be more severe than having a test, people choosing to forgo testing should feel able to reconsider their decision anytime. Most people did not anticipate strong emotional reactions but thought it would change their lifestyle and would like continued clinical surveillance whatever the result.
High prevalence of V37I genetic variant in the connexin‐26 (GJB2) gene among non‐syndromic hearing‐impaired and control Thai individuals
Authors: Wattanasirichaigoon D , Limwongse C , Jariengprasert C , Yenchitsomanus PT , Tocharoenthanaphol C , Thongnoppakhun W , Thawil C , Charoenpipop D , Pho‐iam T , Thongpradit S , Duggal P
Published: October 2004

Hearing loss is highly prevalent with a worldwide incidence of 1–2 per 1000 newborns. Several previous studies have demonstrated that mutations of connexin 26 (Cx26 or GJB2) are responsible for most cases of the recessive non‐syndromic sensorineural hearing loss (NSSHL). Certain mutations have been described frequently among various populations, which include 35delG, 167delT, and 235delC. Recently, a missense mutation, V37I, was reported as a pathogenic change in East Asian affected individuals. To identify genetic variants associated with NSSHL in Thai population, we performed mutation analysis of Cx26 in 166 unrelated probands with NSSHL and 205 controls. We identified seven novel genetic variants in Cx26. We also identified a high prevalence of the V37I mutation among both affected probands (11.1%) and control subjects (8.5%), which suggests that the pathologic role of V37I may be modified by other genes. Our data support previous studies that show heterogeneity in the frequencies and types of mutations in Cx26 within populations and among ethnicities and that before clinical significance and causality can be attributed to a genetic variant, functional characterization is necessary.
Exploration of the impact of messages about genes and race on lay attitudes
Authors: Condit CM , Parrott RL , Bates BR , Bevan J , Achter PJ
Published: October 2004

The effect of messages about genetics on lay audiences was assessed through an experimental study that exposed participants (n = 96) to a Public Service Announcement about race, genes, and heart disease. Participants who received a message that specified either ‘Whites’ or ‘Blacks’ as the subject of the message demonstrated elevated levels of racism, genetic basis for racism, and one dimension of genetic discrimination as compared to those receiving a version of the message with no race specification or in a no‐message control condition. The presentation of such messages to the public is not recommended until additional research clarifies this finding and perhaps describes mitigating vocabularies or approaches.
SDHB, SDHC, and SDHD mutation screen in sporadic and familial head and neck paragangliomas
Authors: Mhatre AN , Li Y , Feng L , Gasperin A , Lalwani AK
Published: October 2004

Mutations within three genes, SDHB, SDHC, and SDHD, encoding distinct subunits of a hetero‐oligomeric protein known as the mitochondrial complex II, a component of the mitochondrial electron transport chain and the Krebs cycle have been implicated in the pathogenesis of hereditary paraganglioma (PGL). This study describes a mutation screen of SDHB, SDHC, and SDHD in blood and tumor samples of 14 sporadic and three familial cases of head and neck PGL (HNP). Germline mutations in SDHB and SDHD were identified in two of the three affected individuals with familial HNP. The SDHB mutation was a novel 3 base pair, in‐frame deletion of AGC at nucleotide 583–585 encoding serine (delS195). The SDHD mutation was a C to T transition within codon 81 causing substitution of proline with leucine (P81L). In contrast to familial cases, no germline or somatic mutations were identified in the 14 sporadic cases of HNP. The presence of mutations within SDHB and SDHD in two of the three samples of familial PGLs and absence of mutations in sporadic cases is consistent with the significant contribution of these genes to familial but not sporadic PGL. The etiology of sporadic PGL remains to be elucidated.
The clinical evaluation and pregnancy outcome of euploid fetuses with increased nuchal translucency
Authors: Maymon R , Herman A
Published: October 2004

This review aims to address the systematic work‐up and counseling throughout pregnancies with increased nuchal translucency (NT) in euploid fetuses. Original articles from peer‐reviewed English‐language journals between 1997 and 2003 were studied. They all included descriptions of pregnancy outcomes of euploid fetuses with increased NT. Eleven studies reporting on the pregnancy outcome of 2128 euploid fetuses with increased NT (≥3 mm or ≥95 centile) were retrieved by our literature search. A statistical analysis was conducted for assessing the consistency of effects across studies. The χ2 tests were applied to verify the homogeneity of the results from different series. A significant difference was found between the studies even when the results were analyzed separately according to various NT cutoff levels (i.e. ≥3 mm, ≥3.5–4 mm, and ≥95 centile). These discrepancies suggest that those studies are significantly different and therefore, cannot be combined for meta‐analysis. Of all the reported series, 2.2–10.6% of the fetuses have miscarried and 0.5–15.8% ended in perinatal death. There was an overall rate of 0.5–12.7% neurodevelopmental problems, and 2.1–7.6% of the malformations which were undiagnosed before birth. Importantly, 70–90% fetuses had normal outcomes. A detailed two‐step anomaly scan including midgestation fetal echocardiography should be part of perinatal management of pregnancies with increased fetal NT. Data on relevant family history and persistence of nuchal edema provide additional relevant information for planning pregnancy management.
A_16_C haplotype in the FcεRIβ gene confers a higher risk for atopic asthma in the Indian population
Authors: Sharma S , Nagarkatti R , B‐Rao C , Niphadkar PV , Vijayan V , Sharma SK , Ghosh B
Published: October 2004

We conducted a case‐control study aimed at identifying polymorphisms and haplotypes in the FcεRIβ gene associated with asthma and its associated phenotypes such as serum IgE levels. A G/A polymorphism in intron 2, a (CA)n repeat polymorphism in intron 5, and a C/T polymorphism in 3′‐UTR, encompassing a length of 8.74 Kb, were genotyped, and haplotypes were generated for unrelated patients and healthy volunteers in two independent cohorts. A significant association was observed at the level of alleles and genotypes studied with asthma independently in the two cohorts (p < 0.05). A change in CC_AA genotype combination to a non‐CC_AA genotype was associated with reduced risk for asthma. Interestingly, a three‐locus haplotype, A_16_C, was found to be significantly associated with asthma (p = 10−5 in cohort A and p = 0.004 in cohort B). On the other hand, the haplotype G_18_T was found to be negatively associated with asthma (p = 0.007 in cohort A and p = 0.0004 in cohort B). This is the first study identifying a haplotype A_16_C that predisposes individuals to asthma in the Indian population.