bluuebunny/crossref_metadata_2025 huggingface dataset:
Cyclin and Cyclin-Dependent Kinase Substrate Requirements for Preventing Rereplication Reveal the Need for Concomitant Activation and Inhibition
Authors: Ikui Amy E , Archambault Vincent , Drapkin Benjamin J , Campbell Veronica , Cross Frederick R
Published: December 2006

DNA replication initiation in S. cerevisiae is promoted by B-type cyclin-dependent kinase (Cdk) activity. In addition, once-per-cell-cycle replication is enforced by cyclin-Cdk-dependent phosphorylation of the prereplicative complex (pre-RC) components Mcm2-7, Cdc6, and Orc1-6. Several of these controls must be simultaneously blocked by mutation to obtain rereplication. We looked for but did not obtain strong evidence for cyclin specificity in the use of different mechanisms to control rereplication: both the S-phase cyclin Clb5 and the mitotic cyclins Clb1–4 were inferred to be capable of imposing ORC-based and MCM-based controls. We found evidence that the S-phase cyclin Clb6 could promote initiation of replication without blocking reinitiation, and this activity was highly toxic when the ability of other cyclins to block reinitiation was prevented by mutation. The failure of Clb6 to regulate reinitiation was due to rapid Clb6 proteolysis, since this toxic activity of Clb6 was lost when Clb6 was stabilized by mutation. Clb6-dependent toxicity is also relieved when early accumulation of mitotic cyclins is allowed to impose rereplication controls. Cell-cycle timing of rereplication control is crucial: sufficient rereplication block activity must be available as soon as firing begins. DNA rereplication induces DNA damage, and when rereplication controls are compromised, the DNA damage checkpoint factors Mre11 and Rad17 provide additional mechanisms that maintain viability and also prevent further rereplication, and this probably contributes to genome stability.
Evolution of Different Y Chromosomes in Two Medaka Species,Oryzias dancenaandO. latipes
Authors: Takehana Yusuke , Demiyah Diana , Naruse Kiyoshi , Hamaguchi Satoshi , Sakaizumi Mitsuru
Published: December 2006

Although the sex-determining gene DMY has been identified on the Y chromosome in the medaka (Oryzias latipes), this gene is absent in most Oryzias species, suggesting that closely related species have different sex-determining genes. Here, we investigated the sex-determination mechanism in O. dancena, which does not possess the DMY gene. Since heteromorphic sex chromosomes have not been reported in this species, a progeny test of sex-reversed individuals produced by hormone treatment was performed. Sex-reversed males yielded all-female progeny, indicating that O. dancena has an XX/XY sex-determination system. To uncover the cryptic sex chromosomes, sex-linked DNA markers were screened using expressed sequence tags (ESTs) established in O. latipes. Linkage analysis of isolated sex-linked ESTs showed a conserved synteny between the sex chromosomes in O. dancena and an autosome in O. latipes. Fluorescence in situ hybridization (FISH) analysis of these markers confirmed that sex chromosomes of these species are not homologous. These findings strongly suggest an independent origin of sex chromosomes in O. dancena and O. latipes. Further analysis of the sex-determining region in O. dancena should provide crucial insights into the evolution of sex-determination mechanisms in vertebrates.
Five Ovine Mitochondrial Lineages Identified From Sheep Breeds of the Near East
Authors: Meadows Jennifer R S , Cemal Ibrahim , Karaca Orhan , Gootwine Elisha , Kijas James W
Published: December 2006

Archaeozoological evidence indicates that sheep were first domesticated in the Fertile Crescent. To search for DNA sequence diversity arising from previously undetected domestication events, this survey examined nine breeds of sheep from modern-day Turkey and Israel. A total of 2027 bp of mitochondrial DNA (mtDNA) sequence from 197 sheep revealed a total of 85 haplotypes and a high level of genetic diversity. Six individuals carried three haplotypes, which clustered separately from the known ovine mtDNA lineages A, B, and C. Analysis of genetic distance, mismatch distribution, and comparisons with wild sheep confirmed that these represent two additional mtDNA lineages denoted D and E. The two haplogroup E sequences were found to link the previously identified groups A and C. The single haplogroup D sequence branched with the eastern mouflon (Ovis orientalis), urial (O. vignei), and argali (O. ammon) sheep. High sequence diversity (K = 1.86%, haplogroup D and O. orientalis) indicates that the wild progenitor of this domestic lineage remains unresolved. The identification in this study of evidence for additional domestication events adds to the emerging view that sheep were recruited from wild populations multiple times in the same way as for other livestock species such as goat, cattle, and pig.
Substitution of Critical Isoleucines in the KH Domains of Drosophila Fragile X Protein Results in Partial Loss-of-Function Phenotypes
Authors: Banerjee Paromita , Nayar Shweta , Hebbar Sarita , Fox Catherine F , Jacobs Michele C , Park Jae H , Fernandes Joyce J , Dockendorff Thomas C
Published: December 2006

Fragile X mental retardation proteins (FMRP) are RNA-binding proteins that interact with a subset of cellular RNAs. Several RNA-binding domains have been identified in FMRP, but the contribution of these individual domains to FMRP function in an animal model is not well understood. In this study, we have generated flies with point mutations in the KH domains of the Drosophila melanogaster fragile X gene (dfmr1) in the context of a genomic rescue fragment. The substitutions of conserved isoleucine residues within the KH domains with asparagine are thought to impair binding of RNA substrates and perhaps the ability of FMRP to assemble into mRNP complexes. The mutants were analyzed for defects in development and behavior that are associated with deletion null alleles of dfmr1. We find that these KH domain mutations result in partial loss of function or no significant loss of function for the phenotypes assayed. The phenotypes resulting from these KH domain mutants imply that the capacities of the mutant proteins to bind RNA and form functional mRNP complexes are not wholly disrupted and are consistent with biochemical models suggesting that RNA-binding domains of FMRP can function independently.
An Unusual Pattern of Spontaneous Mutations Recovered in the Halophilic Archaeon Haloferax volcanii
Authors: Mackwan Reena R , Carver Geraldine T , Drake John W , Grogan Dennis W
Published: December 2006

Spontaneous mutations in the orotate:phosphoribosyl transferase (pyrE2) gene of the halophilic archaeon Haloferax volcanii were selected by 5-fluoroorotic acid plus uracil at a rate of ∼2 × 10−8/cell division in fluctuation and null-fraction tests but ∼6 × 10−8/cell division in mutation-accumulation tests. The corresponding genomic mutation rates were substantially lower than those observed for other mesophilic microbial DNA genomes on the basis of similar target genes. The mutational spectrum was dominated by indels adding or deleting multiples of 3 bp. Properties of the organism contributing to this unusual mutational pattern may include phenotypic lag caused by a high chromosomal copy number and efficient promotion of strand misalignments by short direct repeats.
Assistive Technology Use Among Adolescents and Young Adults With Spina Bifida
Authors: Johnson Kurt L. , Dudgeon Brian , Kuehn Carrie , Walker William
Published: December 2006

Objectives. We sought to determine the use of assistive technology among a population of individuals with spina bifida.

Methods. We performed a descriptive analysis of individuals aged 13 to 27 years diagnosed with myelomeningocele (n=348) using data obtained from an existing database at Children’s Hospital and Regional Medical Center, Seattle, Washington. We summarized disease characteristics, utilization of assistive technology, community and self-care independence, and other variables.

Results. Eighty-four percent of the respondents lived with at least 1 of their natural parents. Fifty-seven percent used wheelchairs, 35% used braces, and 23% used walking aids. Independent self-care was a common skill, but 72% reported limited participation in structured activities. Half were aged 18 years or older; of those, only 50% had completed high school and 71% were unemployed. Those aged younger than 18 years were all still in school (100%).

Conclusions. Adolescents and young adults with spina bifida rely on assistive technology and specialized care routines to maintain their health. Assistive technology use for mobility is common; little is known about secondary complications associated with use of these technologies or the use of assistive technology to address learning disabilities and other societal barriers. Underutilization of assistive technology could delay successful transitions to independent living and community participation.
Early Otitis Media Among Minnesota American Indians: The Little Ears Study
Authors: Daly Kathleen A. , Pirie Phyllis L. , Rhodes Kristine L. , Hunter Lisa L. , Davey Cynthia S.
Published: December 2006

Objectives. We examined relationships between otitis media risk factors, sociodemographic characteristics, and maternal knowledge and attitudes and early onset of otitis media.

Methods. Pregnant women from Minnesota American Indian reservations and an urban clinic were enrolled in our study between 1998 and 2001. Follow-up was performed on enrollees’ infants until the children were 2 years old. Research nurses collected data by ear examination, from interviews and questionnaires given to enrolled mothers, and otitis media episodes that were abstracted from medical records.

Results. Sixty-three percent of infants had experienced an otitis media episode by 6 months of age. Logistic regression analyses showed that maternal otitis media history, infant history of upper respiratory infection, and compliance with study visits were significantly related to early otitis media onset. Although high percentages of infants were exposed to cigarette smoke and other children and were formula fed, these factors were not related to otitis media. Mothers’ prenatal awareness of otitis media risks associated with environmental tobacco smoke exposure and formula feeding did not predict their postpartum behaviors.

Conclusions. We found that infant history of upper respiratory infection and maternal otitis media history are risk factors for early otitis media in American Indian infants. Mothers’ prepartum knowledge and attitudes regarding otitis media did not predict their postpartum avoidance of risk behaviors.
The Effect of Poverty and Caregiver Education on Perceived Need and Access to Health Services Among Children With Special Health Care Needs
Authors: Porterfield Shirley L. , McBride Timothy D.
Published: December 2006

Objectives. We examined the association between several variables and the use of specialist physician services, developmental therapies, and prescription medications among children with special health care needs (N=38866).

Methods. We used a bivariate probit model to estimate whether a given child needed specialized services and whether that child accessed those services; we controlled for activity limitations and severity of special needs. Variables included family income, mother’s (or other caregiver’s) educational level, health insurance coverage, and perceived need for specialized services. We used data from the 2001 National Survey of Children with Special Health Care Needs.

Results. Lower-income and less-educated parents were less likely than higher-income and more-educated parents to say their special needs children needed specialized health services. The probability of accessing specialized health services—when needed—increased with both higher family income and insurance coverage.

Conclusions. Children with special health care needs have less access to health services because their parents do not recognize the need for those services. An intervention in the form of information at the family level may be an appropriate policy response.
Framing the Public Health of Caregiving
Authors: Talley Ronda C. , Crews John E.
Published: December 2006

Caregiving has only recently been acknowledged by the nation as an important topic for millions of Americans. A psychological or sociological approach to care-giving services has been most often applied, with little attention to the population-based public health outcomes of caregivers.

We conceptualize caregiving as an emerging public health issue involving complex and fluctuating roles. We contend that caregiving must be considered in the context of life span needs that vary according to the ages, developmental levels, mental health needs, and physical health demands of both caregivers and care recipients.
Exposure to Lead and Length of Time Needed to Make Homes Lead-Safe for Young Children
Authors: Zierold Kristina M. , Havlena Jeff , Anderson Henry
Published: December 2006

Objectives. We determined the length of time needed to make homes lead-safe in a population of children aged 0 to 6 years with blood lead levels (BLLs) of 20 micrograms per deciliter (μg/dL) or greater. Reducing this time would reduce children’s exposure to lead.

Methods. Data came from the Wisconsin Childhood Lead Poisoning Prevention Program’s comprehensive blood lead surveillance system. Analysis was restricted to children whose first BLL test value during 1996–1999 was between 20 and 40 μg/dL and for whom housing intervention data were available (n=382).

Results. The median length of time required to make a home lead-safe was 465 days. Only 18% of children lived in homes that were made lead-safe within 6 months; 45% lived in homes requiring more than 18 months to be lead-safe.

Conclusions. Efforts are needed to reduce the time it takes to make a home lead-safe. Although abatement orders always include time limits, improved compliance with the orders must be enforced. Greater emphasis should be placed on securing lead-safe or lead-free housing for families, thus reducing lead exposure.
Malnutrition Among Children Younger Than 5 Years-Old in Conflict Zones of Chiapas, Mexico
Authors: Sánchez-Pérez Héctor Javier , Hernán Miguel A. , Ríos-González Adriana , Arana-Cedeño Marcos , Navarro Albert , Ford Douglas , Micek Mark A. , Brentlinger Paula
Published: December 2006

We performed a cross-sectional, community-based survey, supplemented by interviews with community leaders in Chiapas, Mexico, to examine the prevalence and predictors of child malnutrition in regions affected by the Zapatista conflict.

The prevalence rates of stunting, wasting, and underweight were 54.1%, 2.9%, and 20.3%, respectively, in 2666 children aged younger than 5 years. Stunting was associated with indigenous ethnicity, poverty, region of residence, and intracommunity division. The results indicate that malnutrition is a serious public health problem in the studied regions.
The Black–White Disparity in Pregnancy-Related Mortality From 5 Conditions: Differences in Prevalence and Case-Fatality Rates
Authors: Tucker Myra J. , Berg Cynthia J. , Callaghan William M. , Hsia Jason
Published: December 2006

Objectives. We sought to determine whether differences in the prevalences of 5 specific pregnancy complications or differences in case fatality rates for those complications explained the disproportionate risk of pregnancy-related mortality for Black women compared with White women in the United States.

Methods. We used national data sets to calculate prevalence and case-fatality rates among Black and White women for preeclampsia, eclampsia, abruptio placentae, placenta previa, and postpartum hemorrhage for the years 1988 to 1999.

Results. Black women did not have significantly greater prevalence rates than White women. However, Black women with these conditions were 2 to 3 times more likely to die from them than were White women.

Conclusions. Higher pregnancy-related mortality among Black women from preeclampsia, eclampsia, abruptio placentae, placenta previa, and postpartum hemorrhage is largely attributable to higher case-fatality rates. Reductions in case-fatality rates may be made by defining more precisely the mechanisms that affect complication severity and risk of death, including complex interactions of biology and health services, and then applying this knowledge in designing interventions that improve pregnancy-related outcomes.
Effects of Maternal and Provider Characteristics on Up-to-Date Immunization Status of Children Aged 19 to 35 Months
Authors: Kim Sam S. , Frimpong Jemima A. , Rivers Patrick A. , Kronenfeld Jennie J.
Published: December 2006

Objectives. We examined the effects of maternal and provider characteristics on the up-to-date immunization status of children.

Methods. We used data from the 2003 National Immunization Survey to determine variations in children’s up-to-date status in the 4:3:1:3 immunization series.

Results. Low maternal educational levels and low socioeconomic status were associated with high 4:3:1:3 series completion rates. Also, completion rates were high in Hispanic and non-Hispanic Black families with low income-to-poverty ratios.

Conclusions. We found that children of less educated mothers and children in Hispanic and non-Hispanic Black families with low income-to-poverty ratios were more likely to have completed the 4:3:1:3 series. Although the reasons for these results need further exploration in other data sets, possible factors are Hispanics’ positive cultural attitudes regarding the needs and importance of young children and provision of information on immunizations to low-income minority mothers who access government-subsidized health care programs.
Using Participant Event Monitoring in a Cohort Study of Unintentional Injuries Among Children and Adolescents
Authors: Wilkins J.R. , Crawford J. Mac , Stallones Lorann , Koechlin Kathleen M. , Shen Lei , Hayes John , Bean Thomas L.
Published: December 2006

Objectives. We conducted a 3-year cohort study of 407 youths aged 9 to 18 years to develop multivariable risk prediction models of agriculture-related injuries.

Methods. Data were obtained via participant event monitoring, with youths self-reporting injuries and exposures in daily diaries over a 13-week period. We evaluated data quality by comparing injury self-reports with other injury data.

Results. Semilogarithmic plots of rates of all unintentional injuries combined (US data from 2000) as well as of agriculture-related injuries (US and Canadian data from 19 previous studies) graphed as a function of injury severity exhibited linearity, as did plots based on the present results. Severity-specific unintentional injury rates were 1.4- to 4.3-times higher than national rates, suggesting that our methodology can significantly reduce injury underreporting. In addition, at each severity level, estimated agriculture-related injury rates were 5.8- to 9.3-times higher than rates from previous national, regional, and state-based studies.

Conclusions. Our approach to participant event monitoring can be implemented with youths aged 9 to 18 years and will yield reliable daily data on unintentional injuries.
Brief Intervention for Alcohol Use by Pregnant Women
Authors: O’Connor Mary J. , Whaley Shannon E.
Published: December 2006

Objectives. We examined the efficacy of brief intervention as a technique to help pregnant women achieve abstinence from alcohol. A second aim was to assess newborn outcomes as a function of brief intervention.

Methods. Two hundred fifty-five pregnant women who were participants in the Public Health Foundation Enterprises Management Solutions Special Supplemental Nutrition Program for Women, Infants, and Children and who reported drinking alcohol were assigned to an assessment-only or a brief intervention condition and followed to their third trimester of pregnancy. Brief intervention consisted of 10- to 15-minute sessions of counseling by a nutritionist, who used a scripted manual to guide the intervention. Newborn outcomes of gestation, birth-weight, birth length, and viability were assessed.

Results. Women in the brief intervention condition were 5 times more likely to report abstinence after intervention compared with women in the assessment-only condition. Newborns whose mothers received brief intervention had higher birthweights and birth lengths, and fetal mortality rates were 3 times lower (0.9%) compared with newborns in the assessment-only (2.9%) condition.

Conclusions. The success of brief intervention conducted in a community setting by nonmedical professionals has significant implications for national public health policies.
Experiences of Intimate Partner Violence and Related Injuries Among Women in Yokohama, Japan
Authors: Yoshihama Mieko , Horrocks Julie , Kamano Saori
Published: December 2006

We estimated rates of intimate partner violence and related injuries in a sample of 1371 women aged 18 to 49 years in Yokohama, Japan. By the age of 30 years, 14.3% of women who had ever had a partner had experienced violence from that partner, and 3.3% had suffered injuries related to such violence. By the time women had reached the age of 49 years, these percentages were 19% and 4%, respectively. In addition to the need for increased prevention efforts, our findings indicate the need for an expanded legal definition of intimate partner violence in Japan given that the current definition excludes premarital violence.
Changing the Child Labor Laws for Agriculture: Impact on Injury
Authors: Marlenga Barbara , Berg Richard L. , Linneman James G. , Brison Robert J. , Pickett William
Published: December 2006

Objective. The child labor laws are intended to protect young workers from the most dangerous jobs. However, children who work on their parents’ farms are exempt from these laws. We evaluated the potential for preventing the occurrence of farm injuries among children by changing the US Federal Child Labor Laws, Hazardous Occupations Orders for Agriculture.

Methods. A retrospective case series of 1193 farm injuries among children from the United States and Canada was assembled. The Hazardous Occupations Orders were systematically applied to each case. Injury preventability was estimated.

Results. A total of 286 (24%) cases of injury involved immediate family members engaged in farm work. Among these children, 33% of those aged younger than 16 years and 36% of those aged 16 or 17 years were performing work prohibited under the Hazardous Occupations Orders.

Conclusions. Removing the family farm exemption from the Hazardous Occupations Orders and raising the age restriction for performing hazardous agricultural work from 16 to 18 years would be efficacious in preventing the most serious injuries experienced by young family farm workers. Potential reductions in injury would meet Healthy People 2010 goals for reducing traumatic injury in the agricultural sector.
Associations Between Childhood Intelligence and Hospital Admissions for Unintentional Injuries in Adulthood: The Aberdeen Children of the 1950s Cohort Study
Authors: Lawlor Debbie A. , Clark Heather , Leon David A.
Published: December 2006

Objectives. We examined associations between childhood intelligence and hospital admissions for injuries in adulthood.

Methods. Data were derived from a cohort study (=11103) involving individuals born in Aberdeen, Scotland, between 1950 and 1956.

Results. Overall, 1043 cohort members had at least 1 hospital admission resulting from an unintentional injury over 231152 person-years of risk. There were inverse linear associations between childhood intelligence assessed at the ages of 7, 9, and 11 years and having had a hospital admission stemming from an unintentional injury (gender-adjusted hazard ratio [HR] for a 1-standard-deviation increase in intelligence test score at age 7 years = 0.75; 95% confidence interval [CI]=0.70, 0.80). These associations were not markedly affected by adjustment for childhood socioeconomic status, maternal age or height, birthweight, or childhood growth. However, they were attenuated after adjustment for educational attainment (HR=0.85; 95% CI=0.78, 0.91).

Conclusions. Childhood intelligence is related to hospital admissions for injuries in adulthood, and this relationship is partly explained by educational attainment. The association between childhood intelligence and injury may contribute to the association between childhood intelligence and premature mortality demonstrated in several studies.
Time Spent Outdoors at Midday and Children’s Body Mass Index
Authors: Milne Elizabeth , Simpson Julie A. , Johnston Robyn , Giles-Corti Billie , English Dallas R.
Published: December 2006

Objectives. We investigated whether the Kidskin sun protection intervention increased children’s body mass index by reducing the time spent outdoors at midday.

Methods. The Kidskin sun protection intervention involved 1614 Australian school children assigned to 1 of 3 groups: a control group, a moderate-intervention group, or a high-intervention group. Schools in the control group received the standard health curriculum and schools in the intervention groups received a multicomponent intervention. Outcomes included time spent outdoors and nevus development (a marker of melanoma risk). Height and weight were measured at 3 time points. Body mass index was transformed into age- and gender-specific z scores; z scores at each age were modeled simultaneously. Time spent outdoors at ages 10 and 12 years was analyzed using a linear mixed effects modeling.

Results. The proportion of children who were overweight or obese increased with age. The moderate-intervention and control groups had a minimal increase in z score over time, and the z score for the high-intervention group decreased over time. There were no differences among groups with respect to total time outdoors at any age.

Conclusions. It is possible to reduce the time children spend outdoors when ultraviolet radiation is high without producing an unfavorable effect on the children’s body mass index.
Racial and Ethnic Differentials in Overweight and Obesity Among 3-Year-Old Children
Authors: Kimbro Rachel Tolbert , Brooks-Gunn Jeanne , McLanahan Sara
Published: December 2006

Objectives. We estimated racial/ethnic differences in overweight and obesity in a national sample of 3-year-olds from urban, low-income families and assessed possible determinants of differences.

Methods. Survey, in-home observation, and interview data were collected at birth, 1 year, and 3 years. We used logistic regression analyses and adjusted for a range of covariates in examining overweight and obesity differentials according to race/ethnicity.

Results. Thirty-five percent of the study children were overweight or obese. Hispanic children were twice as likely as either Black or White children to be overweight or obese. Although we controlled for a wide variety of characteristics, we were unable to explain either White–Hispanic or Black–Hispanic differences in overweight and obesity. However, birthweight, taking a bottle to bed, and mother’s weight status were important predictors of children’s overweight or obesity at age 3 years.

Conclusions. Children’s problems with overweight and obesity begin as early as age 3, and Hispanic children and those with obese mothers are especially at risk.
Current Priorities in Health Research Funding and Lack of Impact on the Number of Child Deaths per Year
Authors: Leroy Jef L. , Habicht Jean-Pierre , Pelto Gretel , Bertozzi Stefano M.
Published: December 2006

We determined the proportion of research on childhood mortality directed toward better medical technology (i.e., by improving old technology or creating new technology) compared with research on technology delivery and utilization. We also estimated mortality reductions from a research-funding strategy focusing primarily on developing technology compared with one that also focused on delivery and utilization.

Ninety-seven percent of grants were for developing new technologies, which could reduce child mortality by 22%. This reduction is one third of what could be achieved if existing technologies were fully utilized.

There is a serious discrepancy between current research and the research needed to save children’s lives. In addition to increased research on the efficacy of treatment, there is an even greater need for increased research on delivery and use of technology.
Association Between Adult and Childhood Socioeconomic Status and Prevalence of the Metabolic Syndrome in African Americans: The Pitt County Study
Authors: Lucove Jaime C. , Kaufman Jay S. , James Sherman A.
Published: December 2006

We evaluated the association between socioeconomic status (SES) during childhood and adulthood and prevalence of the metabolic syndrome in African Americans. Higher adult educational status and adult skilled occupation were protective against the metabolic syndrome, but no associations were found between the metabolic syndrome and other SES variables. Differences by gender were observed. Improving access to education among African Americans could reduce risk for the metabolic syndrome, but more research is needed in minority populations.
Long-Term Reductions in Mortality Among Children Under Age 5 in Rural Haiti: Effects of a Comprehensive Health System in an Impoverished Setting
Authors: Perry Henry , Berggren Warren , Berggren Gretchen , Dowell Duane , Menager Henri , Bottex Erve , Dortonne Jean Richard , Philippe Francois , Cayemittes Michel
Published: December 2006

Objectives. Evidence regarding the long-term impact of health and other community development programs on under-5 mortality (the risk of death from birth until the fifth birthday) is limited. We compared mortality in a population served by health and other community development programs at the Hôpital Albert Schweitzer (HAS) with national mortality rates among children younger than 5 years for Haiti between 1958 and 1999.

Methods. We collected information on births and deaths in the HAS service area between 1995 and 1999 and assembled previously published under-5 mortality rates at HAS. Published national rates for Haiti served as a comparison.

Results. In the early 1970s, the under-5 mortality rate at HAS declined to a level three fourths lower than that in Haiti nationwide. More recently, HAS rates have remained at one half those for Haiti nationwide. Child survival interventions in the HAS service area were substantially higher than in Haiti nationwide although socioeconomic characteristics and levels of childhood malnutrition were similar in both areas.

Conclusions. HAS’s programs have been responsible for long-term sustained reduction in mortality among children aged less than 5 years. Integrated systems for health and other community development programs could be an effective strategy for achieving the United Nations Millennium Goal to reduce under-5 mortality two thirds by 2015.
FGFR3 Is a Negative Regulator of the Expansion of Pancreatic Epithelial Cells
Authors: Arnaud-Dabernat Sandrine , Kritzik Marcie , Kayali Ayse G. , Zhang You-Qing , Liu Guoxun , Ungles Cory , Sarvetnick Nora
Published: December 2006

Fibroblast growth factors (FGFs) and their receptors (FGFRs) are key signaling molecules for pancreas development. Although FGFR3 is a crucial developmental gene, acting as a negative regulator of bone formation, its participation remains unexplored in pancreatic organogenesis. We found that FGFR3 was expressed in the epithelia in both mouse embryonic and adult regenerating pancreata but was absent in normal adult islets. In FGFR3 knockout mice, we observed an increase in the proliferation of epithelial cells in neonates, leading to a marked increase in islet areas in adults. In vitro studies showed that FGF9 is a very potent ligand for FGFR3 and activates extracellular signal–related kinases (ERKs) in pancreatic cell lines. Moreover, FGFR3 blockade or FGFR3 deficiency led to increased proliferation of pancreatic epithelial cells in vivo. This was accompanied by an increase in the proportion of potential islet progenitor cells. Thus, our results show that FGFR3 signaling inhibits the expansion of the immature pancreatic epithelium. Consequently, this study suggests that FGFR3 participates in regulating pancreatic growth during the emergence of mature islet cells.
Crystal Structure of the Major Diabetes Autoantigen Insulinoma-Associated Protein 2 Reveals Distinctive Immune Epitopes
Authors: Kim Seung Jun , Jeong Dae Gwin , Jeong Sook Kyung , Yoon Tae-Seong , Ryu Seong Eon
Published: December 2006

Insulinoma-associated protein-2 (IA-2) is a major autoantigen in type 1 diabetes that occurs through autoimmune-mediated β-cell destruction. We present here the crystal structure of the protein tyrosine phosphatase (PTP)-like domain of human IA-2. The structure reveals a canonical PTP domain with the closed WPD loop over the active site pocket, explaining the lack of enzyme activity in the native protein. The structural interpretation of previous mutagenesis studies indicates that the B-cell epitopes are concentrated on two distinctive regions on peripheral loops of the central β-sheet surrounding T-cell epitopes within the sheet. The detailed structural information on immune epitopes provides a framework for the future development of immune intervention strategies against diabetes.
Prevention and Treatment of Obesity, Insulin Resistance, and Diabetes by Bile Acid–Binding Resin
Authors: Kobayashi Misato , Ikegami Hiroshi , Fujisawa Tomomi , Nojima Koji , Kawabata Yumiko , Noso Shinsuke , Babaya Naru , Itoi-Babaya Michiko , Yamaji Kaori , Hiromine Yoshihisa , Shibata Masao , Ogihara Toshio
Published: December 2006

Bile acid–binding resins, such as cholestyramine and colestimide, have been clinically used as cholesterol-lowering agents. These agents bind bile acids in the intestine and reduce enterohepatic circulation of bile acids, leading to accelerated conversion of cholesterol to bile acids. A significant improvement in glycemic control was reported in patients with type 2 diabetes whose hyperlipidemia was treated with bile acid–binding resins. To confirm the effect of such drugs on glucose metabolism and to investigate the underlying mechanisms, an animal model of type 2 diabetes was given a high-fat diet with and without colestimide. Diet-induced obesity and fatty liver were markedly ameliorated by colestimide without decreasing the food intake. Hyperglycemia, insulin resistance, and insulin response to glucose, as well as dyslipidemia, were markedly and significantly ameliorated by the treatment. Gene expression of the liver indicated reduced expression of small heterodimer partner, a pleiotropic regulator of diverse metabolic pathways, as well as genes for both fatty acid synthesis and gluconeogenesis, by treatment with colestimide. This study provides a molecular basis for a link between bile acids and glucose metabolism and suggests the bile acid metabolism pathway as a novel therapeutic target for the treatment of obesity, insulin resistance, and type 2 diabetes.
Liraglutide, a Long-Acting Glucagon-Like Peptide-1 Analog, Reduces Body Weight and Food Intake in Obese Candy-Fed Rats, Whereas a Dipeptidyl Peptidase-IV Inhibitor, Vildagliptin, Does Not
Authors: Raun Kirsten , von Voss Pia , Gotfredsen Carsten F. , Golozoubova Valeria , Rolin Bidda , Knudsen Lotte Bjerre
Published: December 2006

Metabolic effects of the glucagon-like peptide-1 analog liraglutide and the dipeptidyl peptidase-IV inhibitor vildagliptin were compared in rats made obese by supplementary candy feeding. Female Sprague-Dawley rats were randomized to 12-week diets of chow or chow plus candy. The latter were randomized for 12 further weeks to continue their diet while receiving 0.2 mg/kg liraglutide twice daily subcutaneously, 10 mg/kg vildagliptin twice daily orally, or vehicle or to revert to chow-only diet. Energy expenditure was measured, and oral glucose tolerance tests (OGTTs) were performed. Body composition was determined by dual-energy X-ray absorptiometry scanning, and pancreatic β-cell mass was determined by histology. Candy feeding increased weight, fat mass, and feeding-associated energy expenditure. Liraglutide or reversal to chow diet fully reversed weight and fat gains. Liraglutide was associated with decreased calorie intake and shifted food preference (increased chow/decreased candy consumption). Despite weight loss, liraglutide-treated rats did not decrease energy expenditure compared with candy-fed controls. Vildagliptin affected neither weight, food intake, nor energy expenditure. OGTTs, histology, and blood analyses indirectly suggested that both drugs increased insulin sensitivity. Liraglutide and vildagliptin inhibited obesity-associated increases in β-cell mass. This was associated with weight and fat mass normalization with liraglutide, but not vildagliptin, where the ratio of β-cell to body mass was low.
Transforming Growth Factor-β2 and Connective Tissue Growth Factor in Proliferative Vitreoretinal Diseases
Authors: Kita Takeshi , Hata Yasuaki , Kano Kumiko , Miura Muneki , Nakao Shintaro , Noda Yoshihiro , Shimokawa Hiroaki , Ishibashi Tatsuro
Published: December 2006

The critical association of connective tissue growth factor (CTGF), which is thought to be one of the downstream mediators of transforming growth factor-β (TGF-β), with vitreoretinal diseases remains to be clarified. In the current study, we first demonstrated the correlation between the concentrations of TGF-β2 as well as CTGF in the vitreous and CTGF gene regulation in cultured hyalocytes. Concentrations of TGF-β2 and CTGF in the vitreous from patients with proliferative vitreoretinal diseases were significantly higher than in those with nonproliferative diseases, and there was a positive correlation between their concentrations (r = 0.320, P < 0.01). Cultured hyalocytes expressed CTGF mRNA, which was enhanced in the presence of TGF-β2, associated with nuclear accumulation of Smad4. TGF-β2–dependent Smad4 translocation and CTGF gene expression were mediated through Rho kinase and at least partially via p38 mitogen-activated protein kinase. Finally, fasudil, a Rho kinase inhibitor already in clinical use, inhibited both Smad4 translocation and CTGF gene expression. In conclusion, combined effects of TGF-β2 and CTGF appear to be involved in the pathogenesis of proliferative vitreoretinal diseases. Hyalocytes may be a possible source of CTGF and thus might play a role in vitreoretinal interface diseases. Furthermore, Rho kinase inhibitors might have therapeutic potential to control fibrotic disorders in the eye.
Dominant-Negative α-Subunit of Farnesyl- and Geranyltransferase Inhibits Glucose-Stimulated, but Not KCl-Stimulated, Insulin Secretion in INS 832/13 Cells
Authors: Veluthakal Rajakrishnan , Kaur Hitchintan , Goalstone Marc , Kowluru Anjaneyulu
Published: December 2006

The majority of small G-proteins undergo posttranslational modifications (e.g., isoprenylation) at their C-terminal cysteine residues. Such modifications increase their hydrophobicity, culminating in translocation of the modified proteins to their relevant membranous sites for interaction with their respective effectors. Previously, we reported glucose-dependent activation and membrane association of Rac1 in INS 832/13 cells. We also demonstrated modulatory roles for Rac1/GDP dissociation inhibitor in glucose-stimulated insulin secretion (GSIS) in INS 832/13 cells, further affirming roles for Rac1 in GSIS. Herein, we demonstrate that geranylgeranyltransferase inhibitor-2147 (GGTI-2147), an inhibitor of protein prenylation, markedly increased cytosolic accumulation of Rac1 and elicited significant inhibition of GSIS from INS 832/13 cells. In the current study, we also examined the localization of protein prenyltransferases (PPTases) and regulation of GSIS by PPTases in INS 832/13 cells. Western blot analyses indicated that the regulatory α-subunit and the structural β-subunit of PPTase holoenzyme are predominantly cytosolic in their distribution. Overexpression of an inactive mutant of the regulatory α-subunit of PPTase markedly attenuated glucose- but not KCl-induced insulin secretion from INS 832/13 cells. Together, our findings provide the first evidence for the regulation of GSIS by PPTase in INS 832/13 cells. Furthermore, they support our original hypothesis that prenylation of specific G-proteins may be necessary for GSIS.
RegII Is a β-Cell Protein and Autoantigen in Diabetes of NOD Mice
Authors: Gurr Werner , Shaw Margaret , Li Yanxia , Sherwin Robert
Published: December 2006

The Reg family of proteins has been studied in the context of growth and regeneration in several organs including pancreatic islets. We previously suggested that Reg proteins act as autoantigens in type 1 diabetes, based on evidence that a member of the Reg family (hepatocellular carcinoma intestine pancreas [HIP]/pancreatitis-associated protein [PAP]) was overexpressed in the islets of a patient who died after sudden onset of type 1 diabetes, and that, in NOD mice, Reg-specific T-cells adoptively transferred diabetes. In the current study, we developed antisera to detect individual Reg members in mouse islets and found that RegIIIα was present in the non–β-cell portion of the islets, while RegII was predominantly expressed in β-cells. Vaccination of NOD mice with the separately expressed N-terminal (NtfrII) or C-terminal (CtfrII) portion of RegII revealed a dichotomy: NtfrII vaccination accelerated and CtfrII vaccination delayed type 1 diabetes. Vaccination with CtfrII was more effective when given at later stages in the pathogenesis of type 1 diabetes, a time dependency different from that seen with other antigen-dependent vaccine strategies in NOD mice, which might have therapeutic implications. In conclusion, RegII is a novel β-cell–derived autoantigen in NOD mice. The autoimmune response against this protein may convert a regenerative into an islet-destructive process accelerating development of type 1 diabetes.
A Functional Polymorphism in the Manganese Superoxide Dismutase Gene and Diabetic Nephropathy
Authors: Möllsten Anna , Marklund Stefan L. , Wessman Maija , Svensson Maria , Forsblom Carol , Parkkonen Maikki , Brismar Kerstin , Groop Per-Henrik , Dahlquist Gisela
Published: December 2006

Oxidative stress has been suggested to contribute to the development of diabetic nephropathy. Manganese superoxide dismutase (MnSOD) protects the cells from oxidative damage by scavenging free radicals. The demand for antioxidants is increased by smoking, which could disturb the balance between antioxidants and radicals. The present study aimed to determine whether a valine/alanine polymorphism in MnSOD (V16A, rs4880), alone or in combination with smoking, can contribute to development of diabetic nephropathy in 1,510 Finnish and Swedish patients with type 1 diabetes. Overt diabetic nephropathy (n = 619) was defined as having an albumin excretion rate (AER) >200 μg/min or renal replacement therapy; incipient diabetic nephropathy was defined as having an AER of 20–200 μg/min (n = 336). The control subjects had diabetes duration of ≥20 years, without albuminuria (AER <20 μg/min) and without antihypertensive treatment (n = 555). In addition to male sex and elevated A1C, smoking was significantly associated with diabetic nephropathy (overt plus incipient), odds ratio (OR) 2.00 (95% CI 1.60–2.50). When controlling for age at onset, diabetes duration, A1C, smoking, and sex, the Val/Val genotype was associated with an increase in risk of diabetic nephropathy (1.32 [1.00–1.74], P = 0.049). When evaluating the combined effect of genotype and smoking, we used logistic regression with stratification according to smoking status and genotype. The high-risk group (ever smoking plus Val/Val genotype) had 2.52 times increased risk of diabetic nephropathy (95% CI 1.73–3.69) compared with the low-risk group, but no departure from additivity was found. Our results indicate that smoking and homozygosity for the MnSOD Val allele is associated with an increased risk of diabetic nephropathy, which supports the hypothesis that oxidative stress contributes to the development of diabetic nephropathy.
TIMP-1 Transgenic Mice Recover From Diabetes Induced by Multiple Low-Dose Streptozotocin
Authors: Jiang Hongwei , Zhu Hanyu , Chen Xiangmei , Peng Youming , Wang Jianzhong , Liu Fuyou , Shi Suozhu , Fu Bo , Lu Yang , Hong Quan , Feng Zhe , Hou Kai , Sun Xuefeng , Cai Guangyan , Zhang Xueguang , Xie Yuansheng
Published: December 2006

Type 1 diabetes results from autoimmune destruction of the insulin-producing β-cells of pancreatic islets, of which the capacity for self-replication in the adult is too limited to restore following extensive tissue injury. Tissue inhibitor of metalloproteinase (TIMP)-1 inhibits matrix metalloproteinase activity and regulates proliferation and apoptosis of a variety of cells types, depending on the context. Here, we show that overexpression of human TIMP-1 in pancreatic β-cells of transgenic mice counteracts the cytotoxicity and insulitis induced by multiple low-dose streptozotocin (MLDS). Nontransgenic mice developed severe hyperglycemia, hypoinsulinemia, and insulitis 2 weeks after streptozotocin administration and died within 17 weeks. However, MLDS-treated transgenic mice gradually normalized the metabolic parameters and survived. β-Cell mass increased in parallel as a result of enhancement of β-cell replication. Thus, our results have demonstrated for the first time that overexpression of TIMP-1 in β-cells enhances the replication of pancreatic islets β-cells and counteracts type 1 diabetes, indicating that the TIMP-1 gene may be a potential target to prevent, or even reverse, type 1 diabetes.
Human Islet Amyloid Polypeptide Oligomers Disrupt Cell Coupling, Induce Apoptosis, and Impair Insulin Secretion in Isolated Human Islets
Authors: Ritzel Robert A. , Meier Juris J. , Lin Chia-Yu , Veldhuis Johannes D. , Butler Peter C.
Published: December 2006

Insulin secretion from the 2,000–3,000 β-cells in an islet is a highly synchronized activity with discharge of insulin in coordinate secretory bursts at approximately 4-min intervals. Insulin secretion progressively declines in type 2 diabetes and following islet transplantation. Both are characterized by the presence of islet amyloid derived from islet amyloid polypeptide (IAPP). In the present studies, we examined the action of extracellular human IAPP (h-IAPP) on morphology and function of human islets. Because oligomers of h-IAPP are known to cause membrane disruption, we questioned if application of h-IAPP oligomers to human islets would lead to disruption of islet architecture (specifically cell-to-cell adherence) and a decrease in coordinate function (e.g., increased entropy of insulin secretion and diminished coordinate secretory bursts). Both hypotheses are affirmed, leading to a novel hypothesis for impaired insulin secretion in type 2 diabetes and following islet transplantation, specifically disrupted cell-to-cell adherence in islets through the actions of membrane-disrupting IAPP oligomers.
Pro-Survival Role of Gelsolin in Mouse β-Cells
Authors: Yermen Barbara , Tomas Alejandra , Halban Philippe A.
Published: December 2006

We have previously shown that the Ca2+-dependent actin-severing protein gelsolin plays an important role in regulated insulin secretion. The aim of this study was to determine the role of gelsolin in β-cell survival as it has been shown to play a dual role in apoptosis in other cell types. MIN6 subclones B1 and C3, shown previously to express gelsolin at different levels (B1≫C3 cells), were used for this purpose. We demonstrate that B1 cells have lower levels of apoptosis and active caspase-3 when compared with C3 cells, in both standard (25 mmol/l glucose and 15% FCS) and deprived (5 mmol/l glucose and 1% FCS) conditions. Overexpression of gelsolin resulted in a decrease in the percentage of terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling (TUNEL)+ and active caspase-3+ cells. Conversely, knockdown of gelsolin by RNA interference in B1 cells caused an increase in the number of TUNEL+ and active caspase-3+ cells. Finally, the anti-apoptotic role of gelsolin was confirmed in purified primary mouse β-cells where overexpression of gelsolin resulted in a decrease in the percentage of TUNEL+ cells. In summary, our results show for the first time that gelsolin plays a pro-survival role in pancreatic β-cells.