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1.
Eur J Pediatr Surg ; 2023 Apr 11.
Article in English | MEDLINE | ID: mdl-36882155

ABSTRACT

OBJECTIVE: The aim of this retrospective study was to describe the risk of postoperative recurrence (POR) after ileocecal resection, the occurrence of surgical complications, and identify predictors of these adverse postoperative outcomes in pediatric Crohn's disease (CD). PATIENTS AND METHODS: All the children less than 18 years of age with a diagnosis of CD, who underwent primary ileocecal resection for CD between January 2006 and December 2016 in our tertiary center, were considered for inclusion. Factors related to POR were investigated. RESULTS: A total of 377 children were followed for CD between 2006 and 2016. During this period, 45 (12%) children needed an ileocecal resection. POR was diagnosed in 16% (n = 7) at 1 year and 35% (n = 15) at the end of the follow-up, with a median follow-up of 2.3 years (Q1-Q3 1.8-3.3). Median duration of the postoperative clinical remission was 1.5 years (range 0.5-2). Multivariate Cox regression analysis identified only young age at diagnosis as a risk factor for POR.In total, 7 of the 43 patients (16%) developed severe postoperative complications, defined as requiring surgical, endoscopic, or radiological intervention. The only risk factor was intraoperative abscess. CONCLUSION: Only young age at diagnosis was associated with POR. This information could be useful to develop targeted therapeutic strategies for young CD children. At the end of follow-up with a median follow-up of 2.3 years (Q1-Q3 1.8-3.3), there was no surgical POR: endoscopic dilatation for POR should be considered in order to delay or prevent surgery.

2.
Arch Pediatr ; 27(7): 393-398, 2020 Oct.
Article in English | MEDLINE | ID: mdl-32921532

ABSTRACT

The current French national guidelines were elaborated by a working group consisting of experts in the field of pediatric endocrinology, rheumatology, hepatogastroenterology, nephrology, and pneumology. A systematic search was undertaken of the literature published between 2008 and 2018 and indexed in PubMed. The recommendations developed were then validated by an external evaluation group comprising representatives from the various highly specialized fields in pediatrics, representatives of the societies and groups supporting the development of the guidelines, and representatives of different healthcare professions. The objective of these guidelines was to detail the current optimal management of children at risk of secondary bone fragility.


Subject(s)
Osteoporosis/etiology , Osteoporosis/therapy , Osteoporotic Fractures/prevention & control , Child , Combined Modality Therapy , France , Humans , Osteoporosis/diagnosis , Osteoporosis/physiopathology , Osteoporotic Fractures/etiology , Prognosis , Quality of Life , Risk Assessment , Risk Factors
3.
Plant Biol (Stuttg) ; 22(2): 203-211, 2020 Mar.
Article in English | MEDLINE | ID: mdl-31762113

ABSTRACT

Species vary in seed size and content of stored reserves, which can be related to dispersal strategies and type of habitat in which they are found. We compare seed carbon and nutrient reserves of anemochorous and zoochorous trees from the Cerrado of central Brazil. We measured seed dry mass, lipids, non-structural carbohydrates (starch and total soluble sugars), carbon and mineral nutrients in ten forest and 13 savanna species, each classified as having wind- or animal-dispersed seeds. We used phylogenetically independent contrasts to test for correlations among these traits. Seeds of anemochorous species were lighter, with higher concentrations of C, N, P, Ca and Mg. Lipids were the dominant carbon reserve for most anemochorous species, underpinning the importance of allocation to compact carbon reserves. Starch, lipids or soluble sugars were the major carbon reserve in zoochorous seeds. Savanna and forest species did not differ in seed mass or in total carbon reserves. However, seeds of forest species had higher concentrations of starch than seeds of savanna species. Lipid and starch negatively correlated across species, suggesting a trade-off between starch and lipids as major seed carbon reserves. Calcium was positively correlated with Mn and B, while Mg was positively correlated with C, N, P, K, S, Zn and B. Potassium, S and Cl were positively correlated, while P was positively correlated with Mg and Zn. Dispersal mode rather than vegetation type constrained seed mass and seed storage allocation patterns in forest and savanna trees. We provide evidence that similar mechanisms are involved in seed storage of carbon and mineral nutrients across species.


Subject(s)
Carbon , Forests , Grassland , Nutrients , Seeds , Trees , Animals , Brazil , Carbon/metabolism , Nutrients/metabolism , Resource Allocation , Seed Dispersal , Seeds/chemistry , Seeds/metabolism , Trees/physiology
4.
Bull Entomol Res ; 107(1): 9-20, 2017 Feb.
Article in English | MEDLINE | ID: mdl-27806733

ABSTRACT

Archeological records attest the early association of Sitophilus with stored cereals from the beginning of agriculture on Asia. The maize weevil (Sitophilus zeamais) became particularly damaging to maize, a cereal crop domesticated on Mesoamerica. We investigated the late evolutionary history of the maize weevil to gain insights on its origin, timing of association with maize, and genealogical relationship to the almost morphologically indistinguishable rice weevil (Sitophilus oryzae). Two mitochondrial genes (cytochrome oxidase subunit I and cytochrome oxidase subunit II) and the nuclear ribosomal gene region were partially sequenced. Analyses showed that the maize weevil shared no haplotypes with the rice weevil; instead, each species exhibited distinct mitogroups and ribogroups. The two weevil species likely split about 8.7 million years ago (95% highest posterior density: 4.0-15.0). Microsatellite data analyses sorted the 309 specimens from 15 populations of the maize weevil into three genotypic groups, which displayed low genetic differentiation and widespread occurrence worldwide. The maize weevil and the rice weevil are each a distinct species; both of which emerged prior to the onset of agriculture. The maize-maize weevil association took place after maize became widespread as a global crop. The maize weevil populations lack spatial genetic structure at the regional, continental, and intercontinental scales.


Subject(s)
Biological Evolution , Gene Flow , Insect Proteins/genetics , Weevils/physiology , Agriculture , Animal Distribution , Animals , Cell Nucleus/genetics , Mitochondrial Proteins/genetics , Phylogeography , Sequence Analysis, DNA , Weevils/genetics , Zea mays/growth & development
5.
Pharmacotherapy ; 36(2): 174-86, 2016 Feb.
Article in English | MEDLINE | ID: mdl-26841333

ABSTRACT

STUDY OBJECTIVE: To assess clinical characteristics, pharmacotherapy treatment patterns, resource utilization and associated charges, and morbidity and mortality outcomes among a real-world cohort of patients with heart failure with reduced ejection fraction (HFrEF) in an academic medical center setting. DESIGN: Retrospective analysis. DATA SOURCE: Electronic health record database that includes clinical, laboratory, and administrative data for all facilities of the University of Utah Health Care System. PATIENTS: A total of 989 adults with prevalent (preexisting) HFrEF, identified by using the International Classification of Diseases, Ninth Revision, Clinical Modification code 428.x (heart failure) between January 1, 2007, and June 30, 2013, and who had a left ventricular ejection fraction of 40% or lower. MEASUREMENTS AND MAIN RESULTS: The cohort had a mean age of 64 ± 15 years and was predominantly white (71%) and male (74%). Patients received ß-blockers, angiotensin-converting enzyme inhibitors (ACEIs) or angiotensin II receptor blockers (ARBs), and aldosterone receptor antagonists (ARAs) at rates of 79%, 69%, and 29%, respectively. Patients achieved target doses of ß-blockers, ACEIs, and ARBs at rates of only 24%, 31%, and 13%, respectively. Overall, 58% of patients were prescribed dual therapy with a ß-blocker and an ACEI or ARB, and 19% were prescribed triple therapy (ß-blocker, an ACEI or ARB, and an ARA). Univariate and multivariate logistic regression models were used to assess the association between baseline characteristics with the presence of triple therapy. Two variables were statistically significant in both models: increasing age was associated with a lower odds of triple therapy (univariate: odds ratio [OR] 0.760, 95% confidence interval [CI] 0.673-0.857; multivariate: OR 0.768, 95% CI 0.625-0.942), whereas receipt of an implantable cardiac device was associated with a 2-fold increase in the odds of triple therapy (univariate: OR 2.1, 95% CI 1.4-3.1; multivariate: OR 2.1, 95% CI 1.3-3.5). During a mean ± SD follow-up of 36 ± 27 months, all-cause mortality was 0.12 per person-year. There were 1311 all-cause hospitalizations of which 611 (47%) were for worsening heart failure. The rate of all-cause and heart failure-specific hospitalizations was 0.44 and 0.21 per person-year of follow-up, respectively. The median length of stay was 6.4 ± 8.8 days, and the median charge was $22,310. The 30-day all-cause readmission rate was 20%, and the primary reason for readmission was heart failure in 65% of cases. CONCLUSION: This study demonstrates the continuing significant disease and economic burden for patients with HFrEF. Challenges remain in utilization of established disease-modifying therapy and in the treatment of patients with HFrEF and multiple comorbidities.


Subject(s)
Adrenergic beta-Antagonists/therapeutic use , Angiotensin Receptor Antagonists/therapeutic use , Angiotensin-Converting Enzyme Inhibitors/therapeutic use , Heart Failure/drug therapy , Heart/drug effects , Mineralocorticoid Receptor Antagonists/therapeutic use , Practice Patterns, Physicians' , Academic Medical Centers , Adrenergic beta-Antagonists/economics , Aged , Angiotensin Receptor Antagonists/economics , Angiotensin-Converting Enzyme Inhibitors/economics , Cohort Studies , Combined Modality Therapy/economics , Cost of Illness , Drug Therapy, Combination/economics , Electronic Health Records , Female , Follow-Up Studies , Health Care Costs , Heart/physiopathology , Heart Failure/economics , Heart Failure/physiopathology , Heart Failure/therapy , Humans , Male , Middle Aged , Mineralocorticoid Receptor Antagonists/economics , Retrospective Studies , Stroke Volume/drug effects , Utah
6.
J Clin Lipidol ; 10(1): 63-71.e1-3, 2016.
Article in English | MEDLINE | ID: mdl-26892122

ABSTRACT

BACKGROUND: Statins have demonstrated significant benefit in reducing cardiovascular disease (CVD) risk. OBJECTIVE: To evaluate statin treatment patterns by intensity, elevated low-density lipoprotein cholesterol (LDL-C) levels, and cardiovascular (CV) events in high-risk CVD patients. METHODS: Patients included were aged ≥ 18 years, with a coronary heart disease (CHD; Jan 1, 2007-Dec 31, 2011, index date) or CHD risk equivalent (CHD RE) diagnosis (Jan 1, 2007-Dec 31, 2010, index date), in the Truven MarketScan claims database, continuously enrolled for 2 years pre- and up to 1 (CHD) or 2 (CHD RE) years post-index. Patients with CHD, CHD RE, rhabdomyolysis, or chronic kidney disease any time pre-index were excluded. Statin therapy was assessed at baseline, 30, 90, and 365 days post-index. LDL-C values were captured in patients with available data at 30-day intervals up to 1 year. CV events were evaluated up to 1 year post-index. Descriptive statistics were used to report results. RESULTS: There were 175,103 CHD and 68,290 CHD RE patients; 3333 CHD RE patients had post-index CV events. At 1 year, 38.7% of CHD patients and 44.3% of CHD RE patients with post-index CV events were not prescribed statins. Most patients who were prescribed statins, received a moderate-intensity statin. The percentage of patients with LDL-C ≥ 100 mg/dL reduced over time, but at 1 year, 29.3% of CHD and 30.0% of CHD RE patients with post-index CV events had LDL-C ≥ 100 mg/dL. At 1 year post-index, 9.9% CHD and 7.3% CHD RE patients had at least 1 CV event. CONCLUSION: There is room for better LDL-C management among high-risk CVD patients to reduce their overall CV risk.


Subject(s)
Cardiovascular Diseases/drug therapy , Cardiovascular Diseases/metabolism , Cholesterol, LDL/metabolism , Hydroxymethylglutaryl-CoA Reductase Inhibitors/therapeutic use , Cardiovascular Diseases/epidemiology , Cohort Studies , Female , Humans , Male , Middle Aged , Retrospective Studies , Risk , United States
7.
J Community Support Oncol ; 13(3): 95-103, 2015 Mar.
Article in English | MEDLINE | ID: mdl-25880672

ABSTRACT

BACKGROUND: Evaluations of the costs of palliative external beam radiation therapy (EBRT) for treatment of bone metastases are limited. OBJECTIVE: To summarize EBRT lifetime care patterns in deceased men with metastatic prostate cancer treated in a cancer hospital in the United States. METHODS: A retrospective review of electronic health records identified deceased adult prostate cancer (ICD-9 185.xx) patients with bone metastases (ICD-9 198.5) and who were treated for bone pain and metastasis management with EBRT between January 1, 1995 and December 17, 2012. Common Procedural Terminology codes were used to identify all EBRT episodes (total billed EBRT services; initial and final evaluation) to calculate length of EBRT treatments and per episode costs (2011 US$). Bootstrapping approximated the 95% confidence interval for final cost estimates. RESULTS: 176 men were identified; 19 (10.8%) had bone metastases in >1 site. Eighty-nine men (50.6%) received >1 EBRT episode (range, 1-6; median, 2), with first episode length ranging from 1-44 calendar days (mean, 13.4; SD, 8.4) at a mean cost of $7,084 (SD, $4,028). About 70% of costs were attributable to hospital charges and 30% to physician charges. LIMITATIONS: Small sample size limits broad applicability to large populations of men with prostate cancer. CONCLUSION: Care costs for EBRT constitute one of many costs that should be taken into account when planning for palliative care of prostate cancer and bone metastasis.

8.
Mol Ecol Resour ; 15(4): 915-20, 2015 Jul.
Article in English | MEDLINE | ID: mdl-25581442

ABSTRACT

Advances in molecular marker technology have provided new opportunities to study the population genetics of polyploid taxa. Paternity analysis using microsatellite markers can be used in detection of gene flow between individuals and populations, in mating system analysis, to identify factors that influence fecundity and fertility, to identify behaviour of parent-offspring relationships and in the analysis of the reproductive success of different ecological groups. As there is no specific program for carrying out paternity analysis in tetraploid species, specialized software was designed for the assignment of paternity for autotetraploid species. orchard is a novel implementation of exclusion and likelihood statistics for carrying out paternity analysis of autotetraploids. First, the program performs an exclusion method, and then, a likelihood statistic is used with nonexcluded candidate fathers. Optional features include estimation of allele dosage of known mother trees and the estimation of pollen flow distances. orchard was tested using a data set of microsatellite data of Dipteryx odorata, a tetraploid Amazonian tree species.


Subject(s)
Computational Biology/methods , DNA Fingerprinting , Dipteryx/genetics , Dipteryx/physiology , Gene Flow , Reproduction , Microsatellite Repeats , Software
9.
Mol Ecol ; 24(1): 38-53, 2015 Jan.
Article in English | MEDLINE | ID: mdl-25402015

ABSTRACT

Selective logging in Brazil allows for the removal of up to 90% of trees above 50 cm diameter of a given timber species, independent of a species' life history characteristics or how quickly it will recover. The genetic and demographic effects of selective logging on two Amazonian timber species (Dipteryx odorata Leguminosae, Jacaranda copaia Bignoniaceae) with contrasting ecological and reproductive characteristics were assessed in the same forest. Genetic diversity and gene flow were characterized by genotyping adults and seed sampled before and after logging, using hypervariable microsatellite markers. Overall, there were no short-term genetic impacts on the J. copaia population, with commercial application of current Brazilian forest management regulations. In contrast, for D. Odorata, selective logging showed a range of genetic impacts, with a 10% loss of alleles, and reductions in siring by pollen from trees within the 546-ha study area (23-11%) and in the number of pollen donors per progeny array (2.8-1.6), illustrating the importance of the surrounding landscape. Asynchrony in flowering between D. odorata trees led to trees with no breeding partners, which could limit the species reproduction and regeneration under current regulations. The results are summarized with other published studies from the same site and the implications for forest management discussed. The different types and levels of impacts associated with each species support the idea that ecological and genetic information by species, ecological guild or reproductive group is essential in helping to derive sustainable logging guidelines for tropical forests.


Subject(s)
Bignoniaceae/genetics , Dipteryx/genetics , Forestry/methods , Gene Flow , Inbreeding , Trees/genetics , Brazil , Conservation of Natural Resources , Genetic Variation , Genotype , Microsatellite Repeats , Pollen/genetics , Population Dynamics
10.
Heredity (Edinb) ; 115(2): 130-9, 2015 Aug.
Article in English | MEDLINE | ID: mdl-24424164

ABSTRACT

The impact of logging and subsequent recovery after logging is predicted to vary depending on specific life history traits of the logged species. The Eco-gene simulation model was used to evaluate the long-term impacts of selective logging over 300 years on two contrasting Brazilian Amazon tree species, Dipteryx odorata and Jacaranda copaia. D. odorata (Leguminosae), a slow growing climax tree, occurs at very low densities, whereas J. copaia (Bignoniaceae) is a fast growing pioneer tree that occurs at high densities. Microsatellite multilocus genotypes of the pre-logging populations were used as data inputs for the Eco-gene model and post-logging genetic data was used to verify the output from the simulations. Overall, under current Brazilian forest management regulations, there were neither short nor long-term impacts on J. copaia. By contrast, D. odorata cannot be sustainably logged under current regulations, a sustainable scenario was achieved by increasing the minimum cutting diameter at breast height from 50 to 100 cm over 30-year logging cycles. Genetic parameters were only slightly affected by selective logging, with reductions in the numbers of alleles and single genotypes. In the short term, the loss of alleles seen in J. copaia simulations was the same as in real data, whereas fewer alleles were lost in D. odorata simulations than in the field. The different impacts and periods of recovery for each species support the idea that ecological and genetic information are essential at species, ecological guild or reproductive group levels to help derive sustainable management scenarios for tropical forests.


Subject(s)
Bignoniaceae/genetics , Conservation of Natural Resources , Dipteryx/genetics , Forestry , Models, Genetic , Alleles , Brazil , Genetics, Population , Genotype , Microsatellite Repeats , Trees/genetics
11.
Mol Ecol Resour ; 12(6): 1196-7, 2012 Nov.
Article in English | MEDLINE | ID: mdl-23006415

ABSTRACT

This article documents the addition of 96 microsatellite marker loci to the Molecular Ecology Resources Database. Loci were developed for the following species: Clarias batrachus, Marmota himalayana, Schizothorax richardsonii, Sitophilus zeamais and Syagrus romanzoffiana. These loci were cross-tested on the following species: Clarias dussumeri, Clarias gariepinus, Heteropneustus fossilis, Sitophilus granarius and Sitophilus oryzae.


Subject(s)
Computational Biology/methods , Ecology/methods , Microsatellite Repeats , Molecular Biology/methods , Animals , Arecaceae/classification , Arecaceae/genetics , Chordata/classification , Chordata/genetics , Weevils/classification , Weevils/genetics
12.
Arch Pediatr ; 16(4): 368-71, 2009 Apr.
Article in French | MEDLINE | ID: mdl-19250810

ABSTRACT

Duodenal duplication is a rare congenital disorder of the gastrointestinal tract. The presentation is highly variable. We report a case of duodenal duplication presenting with hemorrhagic ascites in a 3-month-old girl. The diagnosis of duodenal duplication can be made preoperatively by resonance magnetic imaging. Surgical resection of the duplication was performed. Microscopic examination of the specimen confirmed the duodenal duplication. To our knowledge, this is the 1st reported case of hemorrhagic ascites caused by duodenal duplication and demonstrated by resonance magnetic imaging.


Subject(s)
Ascites/etiology , Duodenum/abnormalities , Hemorrhage/etiology , Duodenum/pathology , Female , Humans , Infant , Magnetic Resonance Imaging
13.
Mol Ecol Resour ; 9(6): 1542-4, 2009 Nov.
Article in English | MEDLINE | ID: mdl-21564953

ABSTRACT

Dipteryx odorata is an intensely exploited Amazonian tree legume. Microsatellite markers were developed to study the genetic structure, gene flow and reproductive biology of D. odorata. Eight highly polymorphic microsatellite markers were isolated from enriched repeat libraries screened for microsatellite repeats. An average of 16 alleles and 0.964 phenotype diversity per locus were found in 76 individuals from the Tapajos National Forest, in the state of Pará in the Brazilian Amazon.

14.
Neuroscience ; 152(4): 1040-53, 2008 Apr 09.
Article in English | MEDLINE | ID: mdl-18355967

ABSTRACT

We have expressed A-FOS, an inhibitor of activator protein-1 (AP-1) DNA binding, in adult mouse striatal neurons. We observed normal behavior including locomotion and exploratory activities. Following a single injection of cocaine, locomotion increased similarly in both the A-FOS expressing and littermate controls. However, following repeated injections of cocaine, the A-FOS expressing mice showed increased locomotion relative to littermate controls, an increase that persisted following a week of withdrawal and subsequent cocaine administration. These results indicate that AP-1 suppresses this behavioral response to cocaine. We analyzed mRNA from the striatum before and 4 and 24 h after a single cocaine injection in both A-FOS and control striata using Affymetrix microarrays (430 2.0 Array) to identify genes mis-regulated by A-FOS that may mediate the increased locomotor sensitization to cocaine. A-FOS expression did not change gene expression in the basal state or 4 h following cocaine treatment relative to controls. However, 24 h after an acute cocaine treatment, 84 genes were identified that were differentially expressed between the A-FOS and control mice. Fifty-six genes are down-regulated while 28 genes are up-regulated including previously identified candidates for addiction including brain-derived neurotrophic factor and period homolog 1. Using a random sample of identified genes, quantitative PCR was used to verify the microarray studies. The chromosomal location of these 84 genes was compared with human genome scans of addiction to identify potential genes in humans that are involved in addiction.


Subject(s)
Cocaine-Related Disorders/genetics , Cocaine/pharmacology , Dopamine Uptake Inhibitors/pharmacology , Gene Expression Regulation/drug effects , Replication Protein C/metabolism , Age Factors , Animals , Animals, Newborn , Behavior, Animal/drug effects , Chromosome Mapping/methods , Cocaine-Related Disorders/physiopathology , Corpus Striatum/drug effects , Dose-Response Relationship, Drug , Exploratory Behavior/drug effects , Gene Expression Regulation/genetics , Locomotion/drug effects , Mice , Mice, Transgenic , Microarray Analysis/methods , Phosphopyruvate Hydratase/genetics , Phosphopyruvate Hydratase/metabolism , RNA, Messenger/metabolism , Replication Protein C/genetics , Time Factors
15.
Mol Ecol Resour ; 8(6): 1288-90, 2008 Nov.
Article in English | MEDLINE | ID: mdl-21586023

ABSTRACT

The Dendrogene Project (Genetic Conservation within Managed Forests in Amazonia) aims to understand the genetic and ecological processes that underpin tree species survival and in particular their response to forest management regimes. As part of the project, we developed eight microsatellite markers for Jacaranda copaia to be used for genetic structure, gene flow and reproductive biology studies. Polymorphism was evaluated using 96 adult trees from the Tapajos National Forest in the Eastern Brazilian Amazon. An average of 22 alleles per locus were detected, with expected heterozygosity ranging from 0.731 to 0.94.

16.
J Evol Biol ; 19(4): 1139-48, 2006 Jul.
Article in English | MEDLINE | ID: mdl-16780514

ABSTRACT

Laboratory mate choice experiments have confirmed species status for cichlid fish in the African Great Lakes that differ in colour and little else. Colour differences between allopatric populations of the South American cichlid genus Apistogramma are known for many species, yet the status of such populations has not been previously tested. Analysis of the genetic relationships and mate choice characteristics of populations previously described as Apistogramma caetei from eastern Amazonia indicates genetic differentiation into at least three allopatric lineages, which also show strong prezygotic isolation through female mate choice, confirming them as Biological species. If future studies confirm that this result is indicative of a general trend, the species richness of the South American cichlid fishes may presently be seriously underestimated.


Subject(s)
Cichlids/physiology , Color , Reproduction , Animals , Female , Male , Sexual Behavior, Animal , Species Specificity
17.
Proc Natl Acad Sci U S A ; 101(9): 3258-63, 2004 Mar 02.
Article in English | MEDLINE | ID: mdl-14978271

ABSTRACT

Leptin is a powerful inhibitor of bone formation in vivo. This antiosteogenic function involves leptin binding to its receptors on ventromedial hypothalamic neurons, the autonomous nervous system and beta-adrenergic receptors on osteoblasts. However, the mechanisms whereby leptin controls the function of ventromedial hypothalamic antiosteogenic neurons remain unclear. In this study, we compared the ability of leptin to regulate body weight and bone mass and show that leptin antiosteogenic and anorexigenic functions are affected by similar amounts of leptin. Using a knock-in of LacZ in the leptin locus, we failed to detect any leptin synthesis in the central nervous system. However, increasing serum leptin level, even dramatically, reduced bone mass. Conversely, reducing serum-free leptin level by overexpressing a soluble receptor for leptin increased bone mass. Congruent with these results, the high bone mass of lipodystrophic mice could be corrected by restoring serum leptin level, suggesting that leptin is an adipocyte product both necessary and sufficient to control bone mass. Consistent with the high bone mass phenotype of lipodystrophic mice, we observed an advanced bone age, an indirect reflection of premature bone formation, in lipodystrophic patients. Taken together, these results indicate that adipocyte-derived circulating leptin is a determinant of bone formation and suggests that leptin antiosteogenic function is conserved in vertebrates.


Subject(s)
Bone Density/physiology , Brain/physiology , Leptin/blood , Animals , Bone Density/drug effects , Cerebral Ventricles , Homeostasis , Humans , Infusions, Parenteral , Leptin/administration & dosage , Leptin/pharmacology , Lipodystrophy/physiopathology , Mice , Mice, Obese , Mice, Transgenic
18.
Cell Death Differ ; 11(3): 270-9, 2004 Mar.
Article in English | MEDLINE | ID: mdl-14647238

ABSTRACT

Fenretinide (HPR), a synthetic retinoid that exhibits lower toxicity than other retinoids, has shown preventive and therapeutic activity against ovarian tumors. Although the growth inhibitory effects of HPR have been ascribed to its ability to induce apoptosis, little is known about the molecular mechanisms involved. Since the proto-oncogene c-Fos has been implicated in apoptosis induction, we analyzed its role in mediating HPR response in a human ovarian carcinoma cell line (A2780) sensitive to HPR apoptotic effect. In these cells, HPR treatment caused induction of c-Fos expression, whereas such an effect was not observed in cells made resistant to HPR-induced apoptosis (A2780/HPR). Moreover, in a panel of other human ovarian carcinoma cell lines, c-Fos inducibility and HPR sensitivity were closely associated. Ceramide, which is involved in HPR-induced apoptosis, was also involved in c-Fos induction because its upregulation by HPR was reduced by fumonisin B(1), a ceramide synthase inhibitor. The causal relationship between c-Fos induction and apoptosis was established by the finding of an increased apoptotic rate in cells overexpressing c-Fos. Similarly to that observed for c-Fos expression, HPR treatment increased c-Jun expression in HPR-sensitive but not in HPR-resistant cells, suggesting the involvement of the transcription factor activating protein 1 (AP-1) in HPR-induced apoptosis. In gene reporter experiments, HPR stimulated AP-1 transcriptional activity and potentiated the AP-1 activity induced by 12-tetradecanoylphorbol 13-acetate. Furthermore, inhibition of AP-1 DNA binding, by transfecting A2780 cells with a dominant-negative Fos gene, caused decreased sensitivity to HPR apoptotic effects. Overall, the results indicate that c-Fos plays a role in mediating HPR-induced growth inhibition and apoptosis in ovarian cancer cells and suggest that c-Fos regulates these processes as a member of the AP-1 transcription factor.


Subject(s)
Antineoplastic Agents/pharmacology , Apoptosis/drug effects , Carcinoma/drug therapy , Fenretinide/pharmacology , Ovarian Neoplasms/drug therapy , Proto-Oncogene Proteins c-fos/metabolism , Antineoplastic Agents/toxicity , Carcinoma/genetics , Carcinoma/metabolism , Carcinoma/pathology , Cell Line, Tumor , Ceramides/metabolism , Enzyme Inhibitors/pharmacology , Female , Fenretinide/toxicity , Fumonisins/pharmacology , Gene Expression Regulation, Neoplastic/drug effects , Genes, Reporter , Genes, jun/drug effects , Green Fluorescent Proteins , Humans , Luminescent Proteins/metabolism , Ovarian Neoplasms/genetics , Ovarian Neoplasms/metabolism , Ovarian Neoplasms/pathology , Proto-Oncogene Mas , Transcription Factor AP-1/metabolism , Up-Regulation
19.
Biochem J ; 360(Pt 3): 599-607, 2001 Dec 15.
Article in English | MEDLINE | ID: mdl-11736649

ABSTRACT

The activator protein 1 (AP-1) transcription factor is composed of heterodimers of the Fos/activating transcription factor (ATF) and Jun subfamilies of basic-region leucine-zipper (B-ZIP) proteins. In order to determine the identities of individual B-ZIP proteins in various AP-1 complexes we tested the effect of dominant-negative mutants to the B-ZIP proteins c-Fos, ATF2, ATF4 and CCAAT-enhancer-binding protein (C/EBP) on the activities of the collagenase and c-Jun promoters. These dominant-negative mutants inhibit DNA binding of wild-type B-ZIP proteins in a leucine-zipper-dependent fashion. Transcription of a collagenase promoter/reporter gene was induced in HepG2 hepatoma cells by expression of c-Fos and c-Jun, administration of PMA ("TPA") or by expression of a truncated form of MEK (mitogen-activated/extracellular-signal-regulated kinase kinase) kinase-1, MEKK1Delta. In all cases, the dominant-negative mutants A-Fos and A-ATF2 decreased collagenase promoter activity. However, A-ATF4 and A-C/EBP had no effect. A-Fos and A-ATF2 also reduced MEKK1Delta-induced stimulation of the c-Jun promoter. In contrast, constitutive c-Jun promoter activity was blocked solely by A-ATF2, strongly suggesting that ATF2 and/or an ATF2-dimerizing protein are of major importance for c-Jun transcription in unstimulated cells. These results demonstrate that AP-1 transcription factors of different compositions control c-jun gene transcription in resting or stimulated cells.


Subject(s)
Collagenases/genetics , Gene Expression Regulation, Neoplastic , MAP Kinase Kinase Kinase 1 , Promoter Regions, Genetic , Proto-Oncogene Proteins c-jun/genetics , Transcription Factor AP-1/metabolism , Amino Acid Sequence , Carcinoma, Hepatocellular , Cells, Cultured , Genes, Reporter , Genes, jun , Humans , Leucine Zippers , Liver Neoplasms , Molecular Sequence Data , Mutagenesis, Site-Directed , Protein Serine-Threonine Kinases/metabolism , Recombinant Proteins/chemistry , Recombinant Proteins/metabolism , Sequence Alignment , Sequence Homology, Amino Acid , Transcription Factor AP-1/chemistry , Transcription Factors/metabolism
20.
Nat Med ; 7(8): 941-6, 2001 Aug.
Article in English | MEDLINE | ID: mdl-11479627

ABSTRACT

Adiponectin is an adipocyte-derived hormone. Recent genome-wide scans have mapped a susceptibility locus for type 2 diabetes and metabolic syndrome to chromosome 3q27, where the gene encoding adiponectin is located. Here we show that decreased expression of adiponectin correlates with insulin resistance in mouse models of altered insulin sensitivity. Adiponectin decreases insulin resistance by decreasing triglyceride content in muscle and liver in obese mice. This effect results from increased expression of molecules involved in both fatty-acid combustion and energy dissipation in muscle. Moreover, insulin resistance in lipoatrophic mice was completely reversed by the combination of physiological doses of adiponectin and leptin, but only partially by either adiponectin or leptin alone. We conclude that decreased adiponectin is implicated in the development of insulin resistance in mouse models of both obesity and lipoatrophy. These data also indicate that the replenishment of adiponectin might provide a novel treatment modality for insulin resistance and type 2 diabetes.


Subject(s)
Adipose Tissue/physiopathology , Insulin Resistance , Intercellular Signaling Peptides and Proteins , Obesity/physiopathology , Proteins/physiology , Adiponectin , Adipose Tissue/metabolism , Amino Acid Sequence , Animals , Leptin/metabolism , Mice , Molecular Sequence Data , Oxidation-Reduction , Receptors, Cytoplasmic and Nuclear/genetics , Receptors, Cytoplasmic and Nuclear/physiology , Signal Transduction , Transcription Factors/genetics , Transcription Factors/physiology , Triglycerides/metabolism
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