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PubMed1993

Centromeric DNA cloned from functional kinetochore fragments in mitotic cells with unreplicated genomes.

Treatment of cells arrested in the cell cycle at the G1/S-phase boundary with 5 mM caffeine induces premature mitosis, resulting in chromosomal fragmentation and detachment of centromere-kinetochore fragments, which are subsequently attached to the mitotic spindle and segregated in anaphase. Taking advantage of this in vivo separation of the centromere, we have developed a procedure for isolation of a centromere-enriched fraction of mitotic chromatin. Using this method, we have isolated and cloned DNA from the centromere-enriched material of Chinese hamster cells. One of the clones thus obtained was characterized in detail. It contains 6 kb of centromere-associated sequence that exhibits no recognizable homology with other mammalian centromeric sequences and is devoid of any extensive repetitive structure. This sequence is present in a single copy on chromosome 1 and is species-specific. Distinctive features of the clone include the presence of several A+T-rich regions and clusters of multiple topoisomerase II consensus cleavage sites and other sequence motifs characteristic of nuclear matrix-associated regions. We hypothesize that these features might be related to the more compact packaging of centromeric chromatin in interphase nuclei and mitotic chromosomes.

Amino Acid Sequence↗
PubMed1996

Identification and characterization of espin, an actin-binding protein localized to the F-actin-rich junctional plaques of Sertoli cell ectoplasmic specializations.

Ectoplasmic specializations are membrane-cytoskeletal assemblages found in Sertoli cells at sites of attachment to elongate spermatids or neighboring Sertoli cells. They are characterized in part by the presence of a unique junctional plaque which contains a narrow layer of parallel actin bundles sandwiched between the Sertoli cell plasma membrane and an affiliated cistern of endoplasmic reticulum. Using a monoclonal antibody, we have identified 'espin,' a novel actin-binding protein localized to ectoplasmic specializations. By immunogold electron microscopy, espin was localized to the parallel actin bundles of ectoplasmic specializations at sites where Sertoli cells contacted the heads of elongate spermatids. The protein was also detected at the sites of ectoplasmic specializations between neighboring Sertoli cells. Espin exhibits an apparent molecular mass of approximately 110 kDa in SDS gels. It is encoded by an approximately 2.9 kb mRNA, which was found to be specific to testis among the 11 rat organs and tissues examined. On the basis of cDNA sequence, espin is predicted to be an 836 amino acid protein which contains 8 ankyrin-like repeats in its N-terminal third, a potential P-loop, two proline-rich peptides and two peptides which contain clusters of multiple glutamates bracketed by arginines, lysines and glutamines in a pattern reminiscent of the repetitive motif found in the protein trichohyalin. The ankyrin-like repeats and a 66 amino acid peptide in the C terminus show significant sequence similarity to proteins encoded by the forked gene of Drosophila. A fusion protein containing the C-terminal 378 amino acids of espin was found to bind with high affinity (Kd = approximately 10 nM) to F-actin in vitro with a stoichiometry of approximately 1 espin per 6 actin monomers. When expressed by transfected NRK fibroblasts, the same C-terminal fragment of espin was observed to decorate actin fibers or cables. On the basis of its structure, localization and properties, we hypothesize that espin is involved in linking actin filaments to each other or to membranes, thereby potentially playing a key role in the organization and function of the ectoplasmic specialization.

Actins↗
PubMed2001

Visceral fat accumulation contributes to insulin resistance, small-sized low-density lipoprotein, and progression of coronary artery disease in middle-aged non-obese Japanese men.

Visceral fat accumulation plays an important role in the occurrence of coronary artery disease (CAD) associated with a cluster of multiple risk factors, such as glucose intolerance, insulin resistance and hyperlipoproteinemia. To clarify the detailed features of these factors, based on visceral fat accumulation, the present study examined the relationship between fat distribution and the characteristics of glucose metabolism and serum lipoproteins in middle-aged non-obese Japanese men. First, the influence of visceral fat accumulation on glucose metabolism, insulin sensitivity, and the extent and severity of coronary artery lesions was investigated in 50 subjects with CAD and compared with 15 control subjects without CAD (Study 1) and with the lipoprotein characteristics in 44 subjects without CAD who were not treated with lipid-lowering drugs (Study 2). Body fat distribution was determined by abdominal computed tomography. In Study 1, the visceral fat area (VFA), blood pressure, fasting immunoreactive insulin (FIRI), and the plasma insulin area (PIA) obtained by oral glucose tolerance test in the subjects with CAD were all significantly higher than in the control subjects. The VFA was significantly correlated with FIRI, the homeostasis model of insulin resistance, PIA and steady state plasma glucose (SSPG) concentration as an index for insulin resistance (r=0.57, p<0.001, r=0.49, p<0.01, r=0.36, p<0.01, and r=0.50, p<0.05, respectively). Although the SSPG concentration did not correlate with the coronary atherosclerosis index as a score of the extent and severity of coronary lesions, the VFA was significantly correlated with this index (r=0.43, p<0.01). In Study 2, the VFA had significant positive correlations with serum total cholesterol, triglyceride, and apolipoprotein B and E levels and the cholesterol and triglyceride concentrations of very-low-density lipoprotein, intermediate-density lipoprotein, and low-density lipoprotein (LDL) fractions. There was a negative correlation between the VFA and LDL particle size (r=-0.34, p<0.05). In conclusion, visceral fat accumulation may contribute to the development of CAD through the progression of insulin resistance and the increase of apo B-containing lipoproteins and small-sized LDLs in middle-aged non-obese Japanese men.

Adipose Tissue↗
PubMed1992

Improving access to health care: case management for vulnerable children.

Health care providers are being confronted by a change in childhood morbidity from primarily physical problems to complex problems rooted in the social, family, and environmental conditions that accompany persistent urban poverty. The clustering of multiple problems in one family necessitates redefining preventive and treatment strategies. Yet the lack of coordination among federal, state and local service programs often exacerbates the vulnerability of these beleaguered children and families. Therapeutic case management is a powerful service coordination strategy for increasing access and improving the health of vulnerable children. An ongoing evaluation of one case management model at the Center for the Vulnerable Child at Children's Hospital in Oakland, California is described in this article. Process evaluation data show this model to be effective in improving comprehensiveness and continuity of care among participating families.

California↗
PubMed2006

Natural biocombinatorics in the polyketide synthase genes of the actinobacterium Streptomyces avermitilis.

Modular polyketide synthases (PKSs) of bacteria provide an enormous reservoir of natural chemical diversity. Studying natural biocombinatorics may aid in the development of concepts for experimental design of genes for the biosynthesis of new bioactive compounds. Here we address the question of how the modularity of biosynthetic enzymes and the prevalence of multiple gene clusters in Streptomyces drive the evolution of metabolic diversity. The phylogeny of ketosynthase (KS) domains of Streptomyces PKSs revealed that the majority of modules involved in the biosynthesis of a single compound evolved by duplication of a single ancestor module. Using Streptomyces avermitilis as a model organism, we have reconstructed the evolutionary relationships of different domain types. This analysis suggests that 65% of the modules were altered by recombinational replacements that occurred within and between biosynthetic gene clusters. The natural reprogramming of the biosynthetic pathways was unambiguously confined to domains that account for the structural diversity of the polyketide products and never observed for the KS domains. We provide examples for natural acyltransferase (AT), ketoreductase (KR), and dehydratase (DH)-KR domain replacements. Potential sites of homologous recombination could be identified in interdomain regions and within domains. Our results indicate that homologous recombination facilitated by the modularity of PKS architecture is the most important mechanism underlying polyketide diversity in bacteria.

Computational Biology↗
PubMed2000

Characterization of the mouse gene for the heavy metal-responsive transcription factor MTF-1.

MTF-1 is a zinc finger transcription factor that mediates the cellular response to heavy metal stress; its targeted disruption in the mouse leads to liver decay and embryonic lethality at day E14. Recently, we have sequenced the entire MTF-1 gene in the compact genome of the pufferfish Fugu rubripes. Here we have defined the promoter sequences of human and mouse MTF-1 and the genomic structure of the mouse MTF-1 locus. The transcription unit of MTF-1 spans 42 kb (compared to 8.5 kb in Fugu) and is located downstream of the gene for a phosphatase (INPP5P) in mouse, human, and fish. In all of these species, the MTF promoter region has the features of a CpG island. In both mouse and human, the 5' untranslated region harbors conserved short reading frames of unknown function. RNA mapping experiments revealed that in these two species, MTF-1 mRNA is transcribed from a cluster of multiple initiation sites from a TATA-less promoter without metal-responsive elements. Transcription from endogenous and transfected MTF-1 promoters was not affected by heavy metal load or other stressors, in support of the notion that MTF-1 activity is regulated at the posttranscriptional level. Tissue Northern blots normalized for poly A+ RNA indicate that MTF-1 is expressed at similar levels in all tissues, except in the testes, that contain more than 10-fold higher mRNA levels.

5' Untranslated Regions↗
PubMed2006

[Arterial hypertension in the elderly: prevalence, associated factors, and control practices in Campinas, São Paulo, Brazil].

The objective of this study was to assess the prevalence of reported hypertension among the elderly in Campinas, São Paulo, Brazil, identifying related factors, the use of healthcare services, and knowledge and practices related to treatment options. This was a cross-sectional population-based study, with stratified clustered multiple-stage sampling. Data analysis for the 426 individuals (60 years of age and older) considered the sampling design and outlining effect. Hypertension prevalence was 51.8% (46.4% in men and 55.9% in women) and was higher among the elderly with less education (55.9%), immigrants from other States (60.2%), and the overweight or obese (57.2%). The results indicate that healthcare services are ensuring access to medical care (71.6% have regular physician appointments) and medication (86.7% take their routine medication), without distinction as to socioeconomic status. However, social inequalities persist in knowledge and use of other measures to control blood pressure, like appropriate diet and exercise, which are also underused by more privileged socioeconomic strata.

Age Distribution↗
PubMed2003

Chondromodulin-I expression in rat articular cartilage.

The localization and expression of chondromodulin-I (ChM-I), an angiogenesis inhibitor, in the rat articular cartilage during maturation from 2 to 10 weeks of age were examined by immunohistochemistry, Western blot analysis and ribonuclease protection assay, and the results were compared with those in the epiphyseal cartilage. ChM-I was found to be diffusely immunostained in the inter-territorial space of the cartilage matrix from the intermediate to the deep layers at the immature stage. As the articular cartilage matured, the immunoreactivity was localized around the hypertrophic chondrocytes in the deep layer and the immunoreactivity became weak after maturation. In contrast, the ChM-I immunoreactivity was intense in the epiphyseal cartilage at all ages examined. ChM-I was detected by Western blotting as a broad band or occasionally as a cluster of multiple bands (approximately 25 kDa) in both the articular and the epiphyseal cartilage. The intensity of the bands decreased gradually with age in the articular cartilage, but was unchanged in the epiphyseal cartilage at all ages. Ribonuclease protection assay revealed that ChM-I mRNA also decreased gradually with age in the articular cartilage in parallel with the maturation of the articular cartilage, while no decrease in ChM-I mRNA was found in the epiphyseal cartilage. The expression of ChM-I mRNA in the articular cartilage was less than that in the epiphyseal cartilage at all ages. The decrease in amount of ChM-I in the mature articular cartilage suggests that ChM-I plays a more important role in the maintenance of avascularity in the immature articular cartilage than in the mature one. The avascular condition may be preserved by angiogenic inhibitors or mechanisms other than ChM-I in the mature articular cartilage.

Aging↗
PubMed2006

Multi-miRNA hairpin method that improves gene knockdown efficiency and provides linked multi-gene knockdown.

A number of natural microRNA (miRNA) hairpins have been found in clusters of multiple identical or different copies, suggesting that effects of miRNAs can be enhanced and multiple genes can be regulated together by encoding multiple miRNA hairpins in a single transcript. Here, we report a simple and effective artificial multi-hairpin method that stimulates production of mature 22-nucleotide small RNAs from modified miRNA hairpins, improves gene knockdown over single-hairpin constructs, and provides linked multi-gene knockdowns.

Base Sequence↗
PubMedDate not supplied

Developmental history of the Glover-Nilsson smoking behavioral questionnaire.

OBJECTIVE: To develop a simple, easily administered pencil-and-paper questionnaire to determine the degree to which behavioral patterns play a role in smoking dependence. METHODS: A modified Delphi technique was used to identify initial questions and to eliminate obvious duplications. Phase 2 utilized multiple statistical methods (principal components analysis, cluster analysis, stepwise multiple linear regression, cross tables, Mantel-Haenzel c2-test, and a Gamma test) to evaluate and reduce the number of questions from 18. RESULTS: These analyses yielded an 11-item questionnaire that can potentially assess behavioral dependence. CONCLUSION: It is hoped that the GN-SBQ will assist physicians, health care providers, and tobacco interventionists in identifying aspects of smoking addiction that are behavioral in nature. The need for future research is discussed.

Attitude to Health↗
PubMedDate not supplied

Unilateral renal cystic disease.

Unilateral renal cystic disease (URCD) is a distinct entity that is one of the renal cystic diseases. URCD consists of a cluster of multiple cysts in part or most of one kidney with no association of cystic disease in the contralateral kidney. URCD is a nonfamilial, nonprogressive disorder and is not related with autosomal dominant polycystic kidney disease (ADPKD). We report a case of URCD with six-year CT follow-up. Confinement of the cystic disease to one kidney with an absence of cysts in other organs such as liver or pancreas distinguish URCD from ADPKD. Absence of an encapsulated mass and intervening normal renal parenchyma between the cysts can differentiate URCD from cystic renal tumors.

Aged↗
PubMed2000

[Detection of epidermal growth factor receptor gene amplification in human laryngeal carcinomas by means of fluorescence in situ hybridization].

OBJECTIVE: To detect epidermal growth factor receptor(EGFR) gene amplification in human laryngeal carcinoma Hep-2 cell line and laryngeal carcinoma tissues. METHODS: The technique of fluorescence in situ hybridization(FISH). RESULTS: The EGFR gene amplification of a laryngeal carcinoma Hep-2 cell line and 5 laryngeal carcinoma tissues were detected by FISH. In the metaphase chromosome and interphase nuclei of Hep-2 cell line and 2 laryngeal carcinoma tissues, distinct cluster and multiple dot signals were found. In the interphase nuclei of the other 3 laryngeal carcinoma tissues, no increase in the number or extent of the hybrid signals was found. CONCLUSION: Compared with normal diploid cell, the EGFR gene amplification was observed at different levels ranging from 2 to 8 folds in metaphase chromosome and interphase nuclei of Hep-2 cell line and 2 laryngeal carcinoma tissues while no amplification was observed in the other 3 laryngeal carcinoma tissues. The results demonstrate that quantitative detection of amplified gene by FISH in the metaphase chromosome and interphase nuclei is useful for detection of laryngeal carcinoma tissues.

ErbB Receptors↗
PubMed2000

Fluoride in water consumed by children in remote areas of Thailand.

The objective of this study was to analyze fluoride content in water for drinking and for use in remote areas of Thailand. Water was sampled from schools and villages along the border by Multiple Stratified Cluster Random Sampling. Fluoride levels of 214 water samples from 48 schools and 48 villages were assessed in triplicate by fluoride ion electrode. The fluoride content in different regions and types of water were statistically analyzed by Kruskal-Wallis test at a significance level of 0.05. Results showed that fluoride in drinking water and water for use from the schools and villages were 0.01-0.37 ppm, 0.01-0.19 ppm, 0.01-0.87 ppm and 0.01-0.92 ppm, respectively. There was no difference in fluoride content in drinking water from various regions (p=0.23). However, there was a statistical difference in fluoride level in water for use (p=0.04, p=0.01) in various regions. The highest fluoride content was found in samples from the central and eastern region (0.19+/-0.24 ppm and 0.29+/-0.28 ppm respectively). When comparing types of water, ie ground water, surface water and rain water, there were differences in fluoride content (p=0.0). Underground water had the highest fluoride content (0.31+/-0.23 ppm).

Child↗
PubMed2001

[Incidence of fractures after the age of 50 years in the Lebanese population and implications in terms of osteoporosis].

BACKGROUND: No comprehensive population-based data is available on the incidence of fractures in Lebanon and the Middle-East. The aim of this study was to estimate the incidence of osteoporotic fractures in the Lebanese population aged 50 years and over. METHODS: In 1997, a cross-sectional population-based random sample of individuals aged 50 years and over was selected using a multiple level cluster sampling technique. Selected individuals responded to an Arabic version of the EULAR questionnaire. A fracture was defined as incident if it had occurred within the last year. The lifetime risk of osteoporotic fracture was estimated using the incidence rate by ten-year age groups assuming that each individual counts on the average for half the interval. RESULTS: 1003 individuals were included. There were 496 men (49.5%) and 507 women (50.5%). Mean age was 61.3 years (CI: 60.8-61.8) with a maximum of 88 years. The observed number of fractures was 111, giving an absolute risk of osteoporotic fractures of 11.1% (CI: 9.1-12.9). It was higher in women, 13.0% (CI: 10.9-15.1) than in men, 8.6% (CI: 6.9-9.3). Female to male ratio was 1.6. The estimated annual incidence was 2.6% (CI: 2.0-3.2), higher in women, 3.8% (CI: 2.2-5.5) than in men, 1.4% (CI: 0.4-2.5). Incident cases were distributed as follows: 4-hip, 4-forearm, 3-spine, and 15 other sites. Annual incidence was higher in women than in men for all sites. Estimated lifetime risk of osteoporotic fracture was 9.3% (CI: 6.7-11.9) in men and 16.7% (CI: 13.4-19.9) in women. CONCLUSION: Our figures are lower than those found in Northern Europe but are higher than in Asian countries, possibly reflecting a west-east gradient in risk factors.

Age Distribution↗
PubMed2000

Dietary fluoride intake of children aged 3-7 years in remote areas of Thailand.

The objectives of this study were to measure dietary fluoride intake in children aged 3-7 years, to correlate dietary fluoride and fluoride content in water for use in schools and to estimate fluoride gained from the daily diet. Fifty food samples were collected in 45 schools under the jurisdiction of the Border Patrol Police Department. The schools were sampled by multiple stratified cluster random sampling. The food samples were weighed, then measured for fluoride content by a microdiffusion method. Statistical analysis was conducted using the Kruskal-Wallis test. Dietary fluoride in each age group was compared by Student's t test. Analysis for the relationship between dietary fluoride and fluoride content in water was done using Kendall's tau-b. Our results showed that the mean of dietary fluoride in lunch was 0.08 +/- 0.1 ppm. There were no differences when comparing dietary fluoride between different regions of Thailand (p = 0.07). No correlation was found between dietary fluoride and fluoride content in water used in different schools (r(tau) = 0.017, p = 0.85). The daily dietary fluoride intake in children aged 3-6 years was 0.002-0.004 mgF/kg bw/day, in children aged 7 years was 0.003-0.004 mgF/kg bw/day in boys and 0.002-0.004 mgF/kg bw/day in girls.

Child↗
PubMed2000

Fluoride analysis of human milk in remote areas of Thailand.

The objective of this study was to measure the fluoride content in human milk collected from mothers living in remote areas of Thailand and to correlate it with fluoride concentrations in drinking water and water for domestic use. Four to five ml of breast milk were sampled from mothers living in villages where schools under the jurisdiction of the Department of Border Patrol Police were located. The schools were sampled by Multiple Stratified Cluster Random Sampling. Fluoride was determined by microdiffusion method. Statistical analysis were made by ANOVA and LSD test. Correlation between fluoride content in milk and water was assessed by Kendall's tau-b. The mean fluoride concentration in breast milk was 0.017+/-0.02 ppm. There was no difference in breast milk fluoride concentration between regions (p=0.6). No correlation was found between breast milk fluoride content and fluoride concentrations in either drinking water or water for domestic use (r(tau) = -0.09, p = 0.32, r(tau) = -0.04, p = 0.65 respectively).

Dental Caries↗
PubMed2001

[Prevalence of dementia in Shanghai urban and rural area].

OBJECTIVE: To study the prevalence and epidemiological characteristics of dementia and their major types in people aged 55 years and old in urban and rural area, Shanghai. METHODS: A sample with 17,018 residents aged 55 years and above from 22 urban and 14 rural communities was drawn through a stratified multiple stage cluster sampling. A door-to-door three-phase procedure was used to investigate the prevalence of dementia. In 1997 and 1998, A brief memory testing by MMSE was administered to all participants. In phase 2, those who scored below the cutoff points and four percent of those whose score was in the normal range were interviewed to identify dementia through a set of diagnostic examinations according to the DSM-IV criteria. In phase 3, a follow-up program was conducted in 1998 for all persons who was involved in phase 2 to identify those with Alzheimer's dementia (AD) and vascular dementia (VaD) by NINCDS-ADRDA and NINDS-AIREN criteria. RESULTS: Of the targeted sample, 15,910 (94.2%) were interviewed. The overall prevalence of dementia was 3.0% in individuals aged 55 years and above, 4.32% in those aged 65 years old and 5.29% in those aged 70 years and above. The age-adjusted prevalence rates of dementia were 2.03%, 3.78% and 5.48% respectively among the age groups mentioned above. For AD the age-adjusted prevalence rates were 1.37%, 2.71% and 4.13% for individuals in above age groups. Of all types of dementia, AD was accounted 72%, followed by VaD the second. The prevalence of AD was 1.41% in man comparing to 2.78% in woman. The age-specific prevalence of AD increased with age. CONCLUSION: The prevalence of dementia was 3.0% in individuals aged 55 years in urban and rural areas in Shanghai. Alzheimer's disease was more frequent than VaD.

Aged↗
PubMed2002

Tetanus toxoid coverage as an indicator of serological protection against neonatal tetanus.

OBJECTIVE: A Multiple-Indicator Cluster Survey (MICS) was conducted at mid-decade in more than 60 developing countries to measure progress towards the year 2000 World Summit for Children goals. These goals included the protection of at least 90% of children against neonatal tetanus through the immunization of their mothers, as measured by tetanus toxoid (TT) coverage. In the Central African Republic (CAR), serological testing was added to the MICS to understand better the relationship between survey estimates of TT coverage and the prevalence of serological protection. METHODS: In the CAR MICS, mothers of children younger than one year of age gave verbal histories of the TT vaccinations they had received, using the MICS TT questionnaire. A subsample of mothers was tested for tetanus antitoxin, using a double-antigen enzyme-linked immunoadsorbent assay (ELISA). Seropositivity was defined as a titre of > or =0.01 IU/ml, and TT coverage was defined as the proportion of mothers protected at delivery, according to their history of TT vaccinations. FINDINGS: Among the 222 mothers in the subsample, weighted TT coverage was 74.4% (95% Confidence Interval (CI); 67.0% - 81.7%) and tetanus antitoxin seroprevalence was 88.7% (95% CI; 83.2% - 94.2%). The weighted median antitoxin titre was 0.35 IU/ml. CONCLUSIONS: Tetanus toxoid coverage in the CAR was lower than the prevalence of serological protection against neonatal tetanus. If this relationship holds for other countries, TT coverage estimates from the MICS may underestimate the extent to which the year 2000 goal for protecting children against neonatal tetanus was reached. We also showed that a high level of serological protection had been achieved in a country facing major public health challenges and resource constraints.

Central African Republic↗