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Contribution of the demographic factor to the migration turnarounds in Japan, Sweden and Canada.

"It is well known that similar changes of migration pattern occurred during recent decades in most developed countries; core regions recorded a greatly decreased net in-migration in the 1970s, but increased net in-migration in the 1980s. Based on shift-share analysis of the migration data of Japan, Sweden and Canada, this paper reveals that changing cohort size, especially related to the fertility fluctuation of baby boom and bust, has played an important role in the turnarounds. Furthermore, it is elucidated from a series of correlation analyses that this demographic factor was closely linked with labour-market restructuring in terms of industrial/occupational employment changes."

Americas↗

Evidence of a founder effect in families with frontotemporal dementia that harbor the tau +16 splice mutation.

The +16 exon 10 splice mutation of the tau gene (microtubule-associated protein tau, MAPT) has been reported in numerous families with frontotemporal dementia (FTD). To date, the majority of these families are from England and Wales in the UK, although families with this mutation have been reported from Australia and the USA. Our own analysis has identified eight families with the +16 MAPT splice mutation from around the Manchester and North Wales areas of the UK. Given the proximity of the UK families to one another it is likely that they are related and represent a single extended pedigree. In order to investigate this possibility, and the possibility that the families with this mutation from London, the USA, and Australia are related, we genotyped 11 microsatellite markers around the tau locus. In most cases (20/25, 80%), a common haplotype, approximately 3 cM in size, was identified. In the remaining cases, this haplotype appears to have been varyingly reduced in size by recombination. We demonstrate that the +16 mutation is on the H1 tau haplotype and that H1 specific polymorphisms are also shared by these families. These data provide evidence that the MAPT +16 splice mutation cases from around the world analyzed in this study are indeed related and represent a single pedigree that probably originated in the North Wales area of the UK. Furthermore, this single large pedigree may be of use in the identification of disease modifying loci in FTD.

Australia↗

Cytogenetic comparison and phylogeny of three species of Hylobatidae.

Representatives of three subgenera of Hylobatidae, Hylobates (Symphalangus) syndactylus, H. (Nomascus) concolor and H. (Hylobates) agilis were compared karyotypically by G-banding, and silver staining. A greater degree of similarity (30-55%) was found among these groups than previous reports suggest; however, these figures are still considerably lower than chromosome similarities characteristic of all other catarrhine groups. Inversion, translocation, fission, and fusion have all played a role in restructuring hylobatid chromosomes since a common hominoid ancestor. H. syndactylus and H. concolor show the greatest G-band correspondence, and in addition share an unusual C-band distribution and an extremely rare nucleolar organizing region placement (on the Y chromosome). The latter two are probably shared derived traits, suggesting that these two species shared a common ancestor not shared by other hylobatids. These data suggest a branching order for these three hylobatid groups different from those derived by other morphological and biochemical methods.

Animals↗

Molecular genetic analysis of Wanggu remains, Inner Mongolia, China.

The Wanggu tribe, which contributed significantly to the foundation of the Yuan Dynasty, was one of the groups living on the Mongolian steppes during the Jin-Yuan period (AD 1127-1368) of Chinese history. However, there has been both archaeological and historical dispute regarding the origin of the ancient tribe. Recently, we discovered human remains of the Wanggu tribe in the Chengbozi cemetery in the Siziwang Banner of Inner Mongolia, China. To investigate the genetic structure of the Wanggu tribe and to trace the origins of the tribe at a molecular level, we analyzed the control-region sequences and coding regions of mitochondrial DNA (mtDNA) from the remains by direct sequencing and restriction-fragment length polymorphism analysis. In combination with mtDNA data of 15 extant Eurasian populations, we performed phylogenetic analysis and multidimensional scaling analysis. Our results show that the genetic structure of the Wanggu tribe in the Jin-Yuan period is a complex matriline, containing admixture from both Asian and European populations. In addition, we reveal that on the basis of mtDNA data, the ancient tribe may share a recent common ancestor with the Turkic-speaking Uzbeks and Uighurs.

Adolescent↗

Clinical implications of benign multiple sclerosis: a 20-year population-based follow-up study.

In 2001, we followed up all patients from the 1991 Olmsted County Multiple Sclerosis (MS) prevalence cohort. We found that the longer the duration of MS and the lower the disability, the more likely a patient is to remain stable and not progress. This is particularly powerful for patients with benign MS with Expanded Disability Status Scale score of 2 or lower for 10 years or longer who have a greater than 90% chance of remaining stable. This is important because these patients represent 17% of the entire prevalence cohort. These data should assist in the shared therapeutic decision-making process of whether to start immunomodulatory medications.

Cohort Studies↗

Association of the major histocompatibility complex with response to infliximab therapy in rheumatoid arthritis patients.

OBJECTIVE: To determine whether major histocompatibility complex (MHC) polymorphisms are associated with a good or poor response to infliximab therapy in patients with rheumatoid arthritis (RA). METHODS: Seventy-eight infliximab-treated patients with RA were genotyped for HLA-DRB1, HLA-DQA1, HLA-DQB1, MHC class I chain-related gene A (MICA) transmembrane polymorphism alleles, and tumor necrosis factor a (TNFa), TNFb, TNFc, TNFd, TNFe, D6S273, HLA-B-associated transcript 2 (BAT2), and D6S2223 microsatellites. Chi-square tests were performed to compare allele proportions between responder and nonresponder patients. A control sample of 342 healthy individuals was also included to detect linkage disequilibrium between pairs of markers. RESULTS: Among responders, the frequency of the TNFa11;b4 minihaplotype was increased (41% versus 16% in nonresponders; P = 0.01) and that of the D6S273_3 allele was decreased (32% versus 56% in nonresponders; P = 0.04). The D6S273_4/BAT2_2 pair was much more frequently observed among responders (46% versus 11% in nonresponders; P = 0.001). When compared with controls, this pair of alleles was found to be associated only with the group of responder patients (46% in responders versus 17% in controls; P = 0.00002). Most of the time, these markers are present in a DRB1*0404/D6S273_4/BAT2_2/TNFa11;b4 context. No statistically significant differences were observed for MICA and D6S2223 polymorphisms and for shared epitope status. CONCLUSION: The data suggest that genetic determinants of response to infliximab therapy exist in the HLA complex.

Adult↗

Integrating worldwide marketing needs and clinical research.

In this era of globalization, expanding research needs, and the necessity of sharing global technologies and worldwide data evaluation techniques, a challenging environment has been created for multinational drug development, clinical testing, and marketing. Integrating worldwide marketing needs and clinical research will become even more significant in the future as harmonization of pharmaceutical industry research and regulatory requirements increase with the unification of the European Economic Community. Marketing and research teams within a pharmaceutical company must work closely together to make the drug being developed appropriate to a global market.

Drug Industry↗

Microarrays in biology and medicine.

The remarkable speed with which biotechnology has become critical to the practice of life sciences owes much to a series of technological revolutions. Microarray is the latest invention in this ongoing technological revolution. This technology holds the promise to revolutionize the future of biology and medicine unlike any other technology that preceded it. Development of microarray technology has significantly changed the way questions about diseases and/or biological phenomena are addressed. This is because microarrays facilitate monitoring the expression of thousands of genes or proteins in a single experiment. This enormous power of microarrays has enabled scientists to monitor thousands of genes and their products in a given living organism in one experiment, and to understand how these genes function in an orchestrated manner. Obtaining such a global view of life at the molecular level was impossible using conventional molecular biological techniques. However, despite all the progress made in developing this technology, microarray is yet to reach a point where all data are obtained, analyzed, and shared in a standardized fashion. The present article is a brief overview of microarray technologies and their applications with an emphasis on DNA microarray.

Animals↗

The role of E-cadherin in low-grade ductal breast tumourigenesis.

Grade I invasive ductal breast carcinomas have a specific pattern of genetic aberrations, namely gain of 1q and loss of 16q. This pattern is very similar to the changes seen in invasive lobular breast carcinomas (ILCs). The gene on 16q involved in ILC is known to be E-cadherin (CDH1). This study has investigated whether the same gene is responsible for grade I invasive ductal carcinoma (IDC), using allele imbalance analysis, mutation screening, and immunohistochemistry (IHC). The data suggest that despite the shared pattern of genetic aberrations seen in grade I IDC and ILC, CDH1 is not the target gene in low-grade ductal tumourigenesis.

Alleles↗

Rank tests for clustered survival data when dependent subunits are randomized.

In clustered survival data, subunits within each cluster share similar characteristics, so that observations made from them tend to be positively correlated. In clinical trials, the correlated subunits from the same cluster are often randomized to different treatment groups. In this case, the variance formulas of the standard rank tests such as the logrank, Gehan-Wilcoxon or Prentice-Wilcoxon, proposed for independent samples, need to be adjusted for intracluster correlations both within and between treatment groups for testing equality of marginal survival distributions. In this paper we derive a general form of simple variance formulas of the rank tests when subunits from the same cluster are randomized into different treatment groups. Extensive simulation studies are conducted to investigate small sample performance of the variance formulas. We compare our non-parametric rank tests based on the adjusted variances with one from a shared frailty model, which is an optimal semi-parametric testing procedure when the intracluster correlations within and between groups are the same.

Animals↗

Inhibition of neutrophil function by human milk.

Human colostrum, the first product of lactation, has antioxidant properties and inhibits selected enzyme and bactericidal activities of human neutrophils. We examined the subsequent product of lactation, mature human milk, with respect to its antioxidant activities, its effects on neutrophil enzyme activities (myeloperoxidase, beta-glucuronidase, and lysozyme), and its effects on neutrophil bactericidal and phagocytic activities. Mature human milk displayed antioxidant characteristics similar to those of human colostrum, reducing cytochrome c and consuming H2O2. Mature milk also displayed colostrum-like characteristics in depressing neutrophil myeloperoxidase and beta-glucuronidase activities, but not in altering lysozyme activity. Neutrophil bactericidal activity against Staphylococcus aureus was depressed by both mature milk and colostrum, without dramatic effects on phagocytic activity. These data show that mature milk shares characteristics with human colostrum that may result in anti-inflammatory effects, but the magnitude of these effects is generally smaller.

Antioxidants↗

Comparative dental development and microstructure of Proconsul teeth from Rusinga Island, Kenya.

Eighteen histological sections were prepared from eleven teeth attributed to Proconsul heseloni and two molar teeth attributed to Proconsul nyanzae. Measurements of spacings and counts of daily incremental markings in both enamel and dentine were possible in the majority of these tooth sections. Measurements of the spacings and angles to the enamel dentine junction (EDJ) of regular striae of Retzius and of equivalent markings in dentine were also made. In addition to these measurements, counts of perikymata were made on replicas of all other Proconsul teeth housed in the National Museum of Kenya, Nairobi, that preserved good perikymata on any aspect of their tooth surface. The sequence of crown formation in Proconsul and the crown formation times of the enamel and dentine were estimated from these data. In addition, the rates of root extension were estimated using the formula derived for this purpose by Shellis (Archs. oral Biol. 29, 697-705, 1984) and estimates of the total period of root formation subsequently made for premolar and molar teeth based on measurements of root length. A composite chart of dental development for P. heseloni is presented which suggests M3 root completion was between six and seven years of age. In general Proconsul molar teeth have high stria angles to the EDJ, a high ratio of enamel formed with respect of dentine formed at the same time, median values of rates of enamel formation close to the EDJ in excess of 4 microns per day and the occasional presence of "S-shaped" striae in the lateral enamel. There is no evidence to suggest that Proconsul from Rusinga Island, Kenya, had relatively thin enamel on molar or premolar teeth. When all of these data are considered in a comparative context, Proconsul emerges overall as hominoid-like in its enamel and dentine microstructure and as most similar to Pongo but with some features shared with Pan and Homo. Similar data for other Miocene primates will have considerable bearing on how these data are interpreted. These new data on dental microanatomy and on dental development in Proconsul make a further contribution to our understanding of the total morphological picture of this early Miocene primate.

Animals↗

High-resolution anatomy from in situ human brain.

We have generated a spatially accurate, high-resolution three-dimensional (3D) volume of brain anatomy from cryosectioned whole human head. The head of a female cadaver was cryosectioned on a heavy duty cryomacrotome (PMV, Stockholm Sweden) modified for quantitative digital image capture. Serial images (1024(2), 24-bit) were captured directly from the cryoplaned specimen blockface in 500-micron intervals and reconstructed to a 3D data volume. Data were placed into the Talairach coordinate system to create a volume of brain anatomy for atlas reference. We resampled the volume at 500 microns along the sagittal, coronal, and horizontal planes and enhanced the images by digitally editing the background. The spatial resolution of the original digitized images provided sufficient anatomic detail to clearly delineate gray and white matter and neural structures, including major fiber pathways, subthalamic nuclei, and laminae. We developed a compact disk and controlling software program to enable the viewer to select planes of orientation, display, and copy individual to sections at higher resolution. Animation proved useful in the conveyance of system anatomy as structures are shown traversing through the neuroaxis. Postmortem cryosectioning paired with this computerized presentation allowed the complete 3D volume data to be distributed and shared as an educational, clinical, and research resource.

Aged↗

Ebola virus inhibits induction of genes by double-stranded RNA in endothelial cells.

Fatal cases of filoviral infection are accompanied by a marked immunosuppression. Endothelial cells play a vital role in the host immune response through the expression of several immunomodulatory genes in addition to the expression of the antiviral genes, 2',5'-oligoadenylate synthetase [2'-5'(A)N], and the double-stranded RNA (dsRNA)-activated protein kinase (PKR). dsRNA, an intermediate generated during viral replication and gene transcription of many viruses, leads to the induction of immunomodulatory genes in endothelial cells. In this report, we show that induction of the major histocompatibility complex class I family of genes, 2'-5'(A)N, interleukin-6 (IL-6), PKR, interferon (IFN)-regulatory factor-1, and intercellular adhesion molecule-1 (ICAM-1) by dsRNA in human umbilical vein endothelial cells is suppressed by infection with the filovirus Ebola-Zaire (EZ). In contrast, induction of IL-6 and ICAM-1 by IL-1 is intact in EZ-infected cells. Gel shift analysis demonstrates that dsRNA-induced protein binding to IFN-responsive elements is strongly suppressed by EZ-IFN, whereas NF-kappa B activation by dsRNA remains intact. We previously reported that IFN signaling is suppressed by EZ infection, and these data strongly suggest that elements shared between IFN and dsRNA signaling are being inhibited by EZ. Inhibition of IFN and dsRNA responsiveness could play a role in the immunosuppression seen in EZ infections and would play a role in the pathogenesis of disease caused by EZ.

2',5'-Oligoadenylate Synthetase↗

Elderly differential resources and patterns of intergenerational exchange.

The relationships between personal resources of elderly parents and intergenerational interactions were studied. On the basis of a fourfold typology of intergenerational exchange, it was hypothesized that the amount of parents' resources, including familial, economic, physical and cognitive resources, would be differentially related to three exchange types: instrumental aid, shared leisure, and affective relations. Data were collected from 145 Jewish elderly persons residing in the community, through structured personal interviews, and analyzed by a stepwise multiple regression procedure. The findings show the multidimensionality of intergenerational bonds, and support the hypothesis that the amount of personal resources is positively related to expressive interactions and inversely to instrumental aid.

Aged↗

Duplication, balancing selection and trans-species evolution explain the high levels of polymorphism of the DQA MHC class II gene in voles (Arvicolinae).

Major histocompatibility complex (MHC) genes play important role in host-parasite interactions and parasites are crucial factors influencing the population dynamics of hosts. We described the structure and diversity of exon 2 of the MHC class II DQA gene in three species of voles (Arvicolinae) exhibiting regular multi-annual fluctuations of population density and analysed the processes leading to the observed MHC polymorphism. By using cloning-sequencing methodology and capillary electrophoresis-single strand conformation polymorphism, we described seven sequences in the water, eight in the common, and seven in the bank voles coming from an area of 70 km(2) around the Nozeroy canton in the Jura Mountains (Franche Comté, France). All exon 2 sequences translate to give unique amino acid sequences and positive selection was found to act very intensively on antigen binding sites. We documented the presence of recombination at vole DQA region but its importance in generating allelic polymorphism seems to be relatively limited. For the first time within rodents, we documented the duplication of the DQA gene in all three species with both copies being transcriptionally active. Phylogenetic analysis of allelic sequences revealed extensive trans-species polymorphism within the subfamily although no alleles were shared between species in our data set. We discuss possible role of parasites in forming the recent polymorphism pattern of the DQA locus in voles.

Alleles↗

High-resolution array-CGH profiling of germline and tumor-specific copy number alterations on chromosome 22 in patients affected with schwannomas.

Schwannomas may develop sporadically or in association with NF2 and schwannomatosis. The fundamental aberration in schwannomas is the bi-allelic inactivation of the NF2 gene. However, clinical and molecular data suggest that these tumors share a common pathogenetic mechanism related to as yet undefined 22q-loci. Linkage studies in schwannomatosis, a condition related to NF2, have defined a candidate 22q-locus and excluded the NF2 gene as the causative germline mutation. Thus, analysis of aberrations in schwannomas may lead to the identification of putative gene(s) involved in the development of schwannoma/schwannomatosis. We profiled a series of 88 schwannomas and constitutional DNA using a tiling path chromosome 22 array. Array-CGH is a suitable method for high-resolution discrimination between germline and tumor-specific aberrations. Previously reported frequencies of 22q-associated deletions in schwannomas display large discrepancies, ranging from 30% to 80%. We detected heterozygous deletions in 53% of schwannomas and the predominant pattern was monosomy 22. In addition, three tumors displayed terminal deletions and four harbored overlapping interstitial deletions of various sizes encompassing the NF2 gene. When profiling constitutional DNA, we identified eight loci that were affected by copy number variation (CNV). Some of the identified CNVs may not be phenotypically neutral and the possible role of these CNVs in the pathogenesis of schwannomas should be studied further. We observed a correlation between the breakpoint position, present in tumor and/or constitutional DNA and the location of segmental duplications. This association implicates these unstable regions in rearrangements occurring both in meiosis and mitosis.

Chromosomes, Human, Pair 22↗

Involvement of alpha-synuclein in Parkinson's disease and other neurodegenerative disorders.

A major step in the elucidation of the pathogenesis of neurodegenerative disorders was the identification of a mutation in the alpha-synuclein gene in autosomal dominant Parkinson's disease (PD). Alpha-synuclein is the main component of Lewy bodies (LB), the neuropathological hallmark of PD. Moreover, a fragment of alpha-synuclein (NAC) is the second major component of amyloid plaques in Alzheimer's disease (AD). Recent studies of other neurodegenerative disorders such as dementia with LB (DLB), multiple system atrophy (MSA) and amyotrophic lateral sclerosis (ALS) also revealed intracellular accumulations of alpha-synuclein in affected brain regions. This may indicate that these disorders partially share common pathogenic mechanisms. Recent data provide first insights into the physiological function of alpha-synuclein and support the concept of an essential role of alpha-synuclein in neurodegeneration. Increasing knowledge on the pathogenic molecular mechanisms of neurodegeneration and of the pathophysiological function of alpha-synuclein in particular may influence future development of therapeutic strategies in neurodegenerative disorders.

Alzheimer Disease↗