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Aims. The main goal of this work is to measure rotation periods of the M-type dwarf stars being observed by the CARMENES exoplanet survey to help distinguish radial-velocity signals produced by magnetic activity from those produced by exoplanets. Rotation periods are also fundamental for a detailed study of the relation between activity and rotation in late-type stars. Methods. We look for significant periodic signals in 622 photometric time series of 337 bright, nearby M dwarfs obtained by long-time baseline, automated surveys (MEarth, ASAS, SuperWASP, NSVS, Catalina, ASAS-SN, K2, and HATNet) and for 20 stars which we obtained with four 0.2–0.8 m telescopes at high geographical latitudes. Results. We present 142 rotation periods (73 new) from 0.12 d to 133 d and ten long-term activity cycles (six new) from 3.0 a to 11.5 a. We compare our determinations with those in the existing literature; we investigate the distribution of Prot in the CARMENES input catalogue, the amplitude of photometric variability, and their relation to v sini and pEW(Hα); and we identify three very active stars with new rotation periods between 0.34 d and 23.6 d. [ABSTRACT FROM AUTHOR]

Keratosis follicularis spinulosa decalvans (KFSD) is a rare, X linked disorder with skin and eye involvement (MIM 308800). We have studied a large British family with KFSD using polymorphic markers from Xp21-p23 and obtained a lod score of 2.056 at theta=0 with markers proximal and distal to the KFSD candidate region Xp22.13-p22.2 identified by Oosterwijk et al. Our data confirm the linkage to Xp22.13-p22.2 observed in the previously reported Dutch family, but fail to narrow the candidate interval for the KFSD locus. [ABSTRACT FROM PUBLISHER]

Aim: To test the hypothesis that overall intelligence quotient (IQ) is decreased in patients with Aarskog syndrome.Methods: 21 boys under 17 years of age with a confirmed clinical diagnosis of Aarskog syndrome were assessed using the Griffiths mental development scales and the British ability scales.Results: IQ ranged from 68 to 128 and followed a normal distribution.Conclusion: This study does not support the hypothesis that Aarskog syndrome is associated with a lowering of mean IQ. [ABSTRACT FROM AUTHOR]

A novel form of severe, X linked mental retardation associated with alpha thalassaemia (ATR-X syndrome) has recently been described. Two affected cousins are described, one of whom has an unusually mild haematological phenotype. HbH inclusions, which are the hallmark of this disease, were only detected in the peripheral red blood cells after repeated observations. [ABSTRACT FROM AUTHOR]

Introduction: Child maltreatment affects a substantial number of children. However current evidence relies on either longitudinal studies, which are complex and resource-intensive, or linked data studies based on social services data, which is arguably the tip of the iceberg in terms of children who are maltreated. Reliable, linked, population-level data on children referred to services due to suspected abuse or neglect will increase our ability to examine risk factors for, and outcomes following, abuse and neglect., Objective: The objective of this project was to create a linkable population level dataset, The Edinburgh Child Protection Dataset (ECPD), comprising all children referred to the Edinburgh Child Protection Paediatric healthcare team due to a concern about their welfare between 1995 and 2015., Methods: The paper presents the process for creating the dataset. The analyses provide examples of available data from the main referrals dataset between 1995 and 2011 (where data quality was highest)., Results: 19,969 referrals were captured, relating to 11,653 children. Of the 19,969 referrals, a higher proportion were girls (54%), although boys were referred for physical abuse more often than girls (41% versus 30%). Younger children were more likely to be referred for physical abuse (35% of 0-4 year olds vs. 27% 15+): older children were more likely to be referred for sexual abuse (48% of 15+ years vs. 18% of 0-4 years). Most referrals came from social workers (46%) or police (31%)., Conclusions: The ECPD offers a unique insight into the characteristics of referrals to child protection paediatric services over a key period in the history of child protection in Scotland. It is hoped that by making these data available to researchers, and able to be easily linked with both mother and child current and future health records, evidence will be created to better support maltreated children and monitor changes over time., Competing Interests: Conflicts of interests: None declared.

Advancing age is the greatest risk factor for developing multiple age-related diseases. Therapeutic approaches targeting the underlying pathways of ageing, rather than individual diseases, may be an effective way to treat and prevent age-related morbidity while reducing the burden of polypharmacy. We harness the Open Targets Genetics Portal to perform a systematic analysis of nearly 1,400 genome-wide association studies (GWAS) mapped to 34 age-related diseases and traits, identifying genetic signals that are shared between two or more of these traits. Using locus-to-gene (L2G) mapping, we identify 995 targets with shared genetic links to age-related diseases and traits, which are enriched in mechanisms of ageing and include known ageing and longevity-related genes. Of these 995 genes, 128 are the target of an approved or investigational drug, 526 have experimental evidence of binding pockets or are predicted to be tractable, and 341 have no existing tractability evidence, representing underexplored genes which may reveal novel biological insights and therapeutic opportunities. We present these candidate targets for exploration and prioritisation in a web application., (© 2023. Springer Nature Limited.)

Perinatal asphyxia contributes significantly to neonatal deaths globally. This may occur due to the effects of various phenomena like uterine rupture, infections, maternal hemodynamic compromise (amniotic fluid embolus), placenta, and umbilical cord (umbilical cord knot, placental abruption, or compression). Perinatal asphyxia is the term used for interrupted blood flow or the exchange of gases in the fetus during the prenatal period. The reduced oxygenation induces a cascade of brain injuries, resulting in long-term damage to the infant's brain. Some infants exposed to perinatal hypoxia-ischemia will make an immediate recovery and have normal survival, while others may suffer from an evolving clinical encephalopathy. This review article focuses on the relationship between the placenta, neonatal encephalopathy, and neurodevelopmental outcome. It also aims to identify possible interventions and drive the focus of policymakers towards issues that evolve around perinatal asphyxia, neonatal encephalopathy, and neonatal care and that have a high impact on infant morbidity in sub-Saharan Africa.

Recurrent miscarriage is classically defined as three or more consecutive pregnancy losses in about 1-5% of couples trying to conceive. However, several researchers have amended this to two or more because of the recent increase in childless miscarriages. Recurrent miscarriage is a clinical challenge for clinicians because there are many possible causes, and diagnostic testing is expensive and time-consuming. Established causes of recurrent miscarriage are antiphospholipid antibodies, uterine anomalies, and abnormal chromosomes in either partner, particularly translocations. Uterine anatomical abnormalities, endocrine abnormalities, infections, immunologic factors, environmental factors, metabolic or hormonal disorders, sperm quality, and maternal and paternal age have each been linked. Among them, the genetic factor plays a significant role in recurrent miscarriage. Approximately 70% of miscarriage conceptions with sporadic spontaneous miscarriage reveal some chromosome abnormality. Specifically, recurrent miscarriage can be caused by a structural or numerical defect in the parents' or fetus' chromosomes. Recurrent miscarriage has been linked to several genes, including those involved in oxidative stress, angiogenesis, clotting, and inflammation. Despite several well-known etiologic factors, the etiology of recurrent miscarriage is unknown in over half of all instances. The current review aims to analyse the role of the genetic basis of recurrent miscarriages.

Objective: To assess feasibility and acceptability of a novel, low-cost "Suction Tube Uterine Tamponade" (STUT) treatment for refractory postpartum hemorrhage (PPH)., Methods: We allocated patients with refractory PPH by randomly ordered envelopes to STUT or routine uterine balloon tamponade (UBT, Ellavi free-flow system) in 10 hospitals in South Africa. In the STUT group, a 24FG Levin stomach tube was inserted into the uterine cavity and vacuum created with a vacuum pump or manual vacuum aspiration syringe., Results: For this internal pilot study, 12 participants were allocated to STUT and 12 to UBT. Insertion failed in one of each group and was recorded as difficult in 3/10 STUT and 4/9 UBT insertions respectively (five missing data). There were two laparotomies and one intensive care unit admission in the UBT group. Pain during STUT insertion was graded as none/mild in 9/10 and severe in 1/10. The experience of the STUT procedure was graded as fine in 4/11 and "uncomfortable but acceptable" in 7/11., Conclusion: STUT is feasible and acceptable, justifying continuation of our trial. These data will also inform a large World Health Organization trial to test effectiveness of uterine tamponade methods. The numbers are too small to support any clinical recommendation., (© 2021 International Federation of Gynecology and Obstetrics.)

Objective: To describe risk factors and outcomes of pregnant women infected with SARS-CoV-2 admitted to South African healthcare facilities., Methods: A population-based cohort study was conducted utilizing an amended International Obstetric Surveillance System protocol. Data on pregnant women with SARS-CoV-2 infection, hospitalized between April 14, 2020, and November 24, 2020, were analyzed., Results: A total of 36 hospitals submitted data on 673 infected hospitalized pregnant women; 217 (32.2%) were admitted for COVID-19 illness and 456 for other indications. There were 39 deaths with a case fatality rate of 6.3%: 32 (14.7%) deaths occurred in women admitted for COVID-19 illness compared to 7 (1.8%) in women admitted for other indications. Of the women, 106 (15.9%) required critical care. Maternal tuberculosis, but not HIV co-infection or other co-morbidities, was associated with admission for COVID-19 illness. Rates of cesarean delivery did not differ significantly between women admitted for COVID-19 and those admitted for other indications. There were 179 (35.4%) preterm births, 25 (4.7%) stillbirths, 12 (2.3%) neonatal deaths, and 162 (30.8%) neonatal admissions. Neonatal outcomes did not differ significantly from those of infected women admitted for other indications., Conclusion: The maternal mortality rate was high among women admitted with SARS-CoV-2 infection and higher in women admitted primarily for COVID-19 illness with tuberculosis being the only co-morbidity associated with admission., (© 2021 International Federation of Gynecology and Obstetrics.)

Objective: To investigate the efficacy of mobile health (mHealth) intervention strategies that delivered either personalized, culturally, and linguistically tailored cell phone voice messages or text messages related to breast cancer and prevention, compared to the control group, to determine which strategy is more likely to increase breast cancer knowledge and screening mammography among low-income Latina immigrants. Methods: This randomized controlled trial assigned 256 Latina immigrants 40 years of age or older to one of three groups: an automated cell phone voice message group, an automated text message group, or the control group (mail). The mHealth intervention employed a comprehensive approach that included breast cancer and prevention education and free mammography screening. Outcome measures included knowledge of breast cancer and breast cancer prevention, and adherence to screening mammography. Results: There was a general increase in breast cancer knowledge after the educational intervention for all the groups [ p  = 0.01, t (199) = 3.996]. Knowledge increase and mammography adherence did not differ based on group. Conclusion: More important than the actual method of communication is how breast cancer and prevention messages are constructed, who the messenger is, and the enabling factors that facilitate screening adherence. A breast cancer preventive intervention program that is personalized, culturally and linguistically tailored, and offers a free or low-cost mammogram holds promise to be an effective method in reaching an underserved Latina population with a high breast cancer burden., Competing Interests: No competing financial interests exist., (© Maria De Jesus et al., 2021; Published by Mary Ann Liebert, Inc.)

Aim: Recently we have observed differences in the ability of metformin and AICAR to repress glucose production from hepatocytes using 8CPT-cAMP. Previous results indicate that, in addition to activating protein kinase A, 8CPT-modified cAMP analogues suppress the nitrobenzylthioinosine (NBMPR)-sensitive equilibrative nucleoside transporter ENT1. We aimed to exploit 8CPT-cAMP, 8CPT-2-Methyl-O-cAMP and NBMPR, which is highly selective for a high-affinity binding-site on ENT1, to investigate the role of ENT1 in the liver-specific glucose-lowering properties of AICAR and metformin., Methods: Primary mouse hepatocytes were incubated with AICAR and metformin in combination with cAMP analogues, glucagon, forskolin and NBMPR. Hepatocyte glucose production (HGP) and AMPK signalling were measured, and a uridine uptake assay with supporting LC-MS was used to investigate nucleoside depletion from medium by cells., Results: AICAR and metformin increased AMPK pathway phosphorylation and decreased HGP induced by dibutyryl cAMP and glucagon. HGP was also induced by 8CPT-cAMP, 8CPT-2-Methyl-O-cAMP and NBMPR; however, in each case this was resistant to suppression by AICAR but not by metformin. Cross-validation of tracer and mass spectrometry studies indicates that 8CPT-cAMP, 8CPT-2-Methyl-O-cAMP and NBMPR inhibited the effects of AICAR, at least in part, by impeding its uptake into hepatocytes., Conclusions: We report for the first time that suppression of ENT1 induces HGP. ENT1 inhibition also impedes uptake and the effects of AICAR, but not metformin, on HGP. Further investigation of nucleoside transport may illuminate a better understanding of how metformin and AICAR each regulate HGP., (© 2018 The Authors. Diabetes, Obesity and Metabolism published by John Wiley & Sons Ltd.)

Many guanide-containing drugs are antihyperglycaemic but most exhibit toxicity, to the extent that only the biguanide metformin has enjoyed sustained clinical use. Here, we have isolated unique mitochondrial redox control properties of metformin that are likely to account for this difference. In primary hepatocytes and H4IIE hepatoma cells we found that antihyperglycaemic diguanides DG5-DG10 and the biguanide phenformin were up to 1000-fold more potent than metformin on cell signalling responses, gluconeogenic promoter expression and hepatocyte glucose production. Each drug inhibited cellular oxygen consumption similarly but there were marked differences in other respects. All diguanides and phenformin but not metformin inhibited NADH oxidation in submitochondrial particles, indicative of complex I inhibition, which also corresponded closely with dehydrogenase activity in living cells measured by WST-1. Consistent with these findings, in isolated mitochondria, DG8 but not metformin caused the NADH/NAD + couple to become more reduced over time and mitochondrial deterioration ensued, suggesting direct inhibition of complex I and mitochondrial toxicity of DG8. In contrast, metformin exerted a selective oxidation of the mitochondrial NADH/NAD + couple, without triggering mitochondrial deterioration. Together, our results suggest that metformin suppresses energy transduction by selectively inducing a state in complex I where redox and proton transfer domains are no longer efficiently coupled., (Copyright © 2017 The Authors. Published by Elsevier B.V. All rights reserved.)

Glycogen synthase kinase-3 (GSK3) regulates many physiological processes through phosphorylation of a diverse array of substrates. Inhibitors of GSK3 have been generated as potential therapies in several diseases, however the vital role GSK3 plays in cell biology makes the clinical use of GSK3 inhibitors potentially problematic. A clearer understanding of true physiological and pathophysiological substrates of GSK3 should provide opportunities for more selective, disease specific, manipulation of GSK3. To identify kinetically favourable substrates we performed a GSK3 substrate screen in heart tissue. Rab-GTPase binding effector protein 2 (RABEP2) was identified as a novel GSK3 substrate and GSK3 phosphorylation of RABEP2 at Ser200 was enhanced by prior phosphorylation at Ser204, fitting the known consensus sequence for GSK3 substrates. Both residues are phosphorylated in cells while only Ser200 phosphorylation is reduced following inhibition of GSK3. RABEP2 function was originally identified as a Rab5 binding protein. We did not observe co-localisation of RABEP2 and Rab5 in cells, while ectopic expression of RABEP2 had no effect on endosomal recycling. The work presented identifies RABEP2 as a novel primed substrate of GSK3, and thus a potential biomarker for GSK3 activity, but understanding how phosphorylation regulates RABEP2 function requires more information on physiological roles of RABEP2.

Metformin is the first-line antidiabetic drug with over 100 million users worldwide, yet its mechanism of action remains unclear. Here the Metformin Genetics (MetGen) Consortium reports a three-stage genome-wide association study (GWAS), consisting of 13,123 participants of different ancestries. The C allele of rs8192675 in the intron of SLC2A2, which encodes the facilitated glucose transporter GLUT2, was associated with a 0.17% (P = 6.6 × 10(-14)) greater metformin-induced reduction in hemoglobin A1c (HbA1c) in 10,577 participants of European ancestry. rs8192675 was the top cis expression quantitative trait locus (cis-eQTL) for SLC2A2 in 1,226 human liver samples, suggesting a key role for hepatic GLUT2 in regulation of metformin action. Among obese individuals, C-allele homozygotes at rs8192675 had a 0.33% (3.6 mmol/mol) greater absolute HbA1c reduction than T-allele homozygotes. This was about half the effect seen with the addition of a DPP-4 inhibitor, and equated to a dose difference of 550 mg of metformin, suggesting rs8192675 as a potential biomarker for stratified medicine., Competing Interests: The authors have declared that no competing interests exist.

Anti-hyperglycaemic effects of the hydroxybenzoic acid salicylate might stem from effects of the drug on mitochondrial uncoupling, activation of AMP-activated protein kinase, and inhibition of NF-κB signalling. Here, we have gauged the contribution of these effects to control of hepatocyte glucose production, comparing salicylate with inactive hydroxybenzoic acid analogues of the drug. In rat H4IIE hepatoma cells, salicylate was the only drug tested that activated AMPK. Salicylate also reduced mTOR signalling, but this property was observed widely among the analogues. In a sub-panel of analogues, salicylate alone reduced promoter activity of the key gluconeogenic enzyme glucose 6-phosphatase and suppressed basal glucose production in mouse primary hepatocytes. Both salicylate and 2,6 dihydroxybenzoic acid suppressed TNFα-induced IκB degradation, and in genetic knockout experiments, we found that the effect of salicylate on IκB degradation was AMPK-independent. Previous data also identified AMPK-independent regulation of glucose but we found that direct inhibition of neither NF-κB nor mTOR signalling suppressed glucose production, suggesting that other factors besides these cell signalling pathways may need to be considered to account for this response to salicylate. We found, for example, that H4IIE cells were exquisitely sensitive to uncoupling with modest doses of salicylate, which occurred on a similar time course to another anti-hyperglycaemic uncoupling agent 2,4-dinitrophenol, while there was no discernible effect at all of two salicylate analogues which are not anti-hyperglycaemic. This finding supports much earlier literature suggesting that salicylates exert anti-hyperglycaemic effects at least in part through uncoupling., (Copyright © 2016 The Authors. Published by Elsevier B.V. All rights reserved.)

In recent decades, the antihyperglycemic biguanide metformin has been used extensively in the treatment of type 2 diabetes, despite continuing uncertainty over its direct target. In this article, using two independent approaches, we demonstrate that cellular actions of metformin are disrupted by interference with its metal-binding properties, which have been known for over a century but little studied by biologists. We demonstrate that copper sequestration opposes known actions of metformin not only on AMP-activated protein kinase (AMPK)-dependent signaling, but also on S6 protein phosphorylation. Biguanide/metal interactions are stabilized by extensive π-electron delocalization and by investigating analogs of metformin; we provide evidence that this intrinsic property enables biguanides to regulate AMPK, glucose production, gluconeogenic gene expression, mitochondrial respiration, and mitochondrial copper binding. In contrast, regulation of S6 phosphorylation is prevented only by direct modification of the metal-liganding groups of the biguanide structure, supporting recent data that AMPK and S6 phosphorylation are regulated independently by biguanides. Additional studies with pioglitazone suggest that mitochondrial copper is targeted by both of these clinically important drugs. Together, these results suggest that cellular effects of biguanides depend on their metal-binding properties. This link may illuminate a better understanding of the molecular mechanisms enabling antihyperglycemic drug action.

Many diseases of aging including AD (Alzheimer's disease) and T2D (Type 2 diabetes) are strongly associated with common risk factors, suggesting that there may be shared aging mechanisms underlying these diseases, with the scope to identify common cellular targets for therapy. In the present study we have examined the insulin-like signalling properties of an experimental AD 8-hydroxyquinoline drug known as CQ (clioquinol). The IIS [insulin/IGF-1 (insulin-like growth factor-1) signalling] kinase Akt/PKB (protein kinase B) inhibits the transcription factor FOXO1a (forkhead box O1a) by phosphorylating it on residues that trigger its exit from the nucleus. In HEK (human embryonic kidney)-293 cells, we found that CQ treatment induces similar responses. A key transcriptional response to IIS is the inhibition of hepatic gluconeogenic gene expression, and, in rat liver cells, CQ represses expression of the key gluconeogenic regulatory enzymes PEPCK (phosphoenolpyruvate carboxykinase) and G6Pase (glucose-6-phosphatase). The effects on FOXO1a and gluconeogenic gene expression require the presence of Zn2+ ions, reminiscent of much earlier studies examining diabetogenic properties of 8-hydroxyquinolines. Comparative investigation of the signalling properties of a panel of these compounds demonstrates that CQ alone exhibits FOXO1a regulation without diabetogenicity. Our results suggest that Zn2+-dependent regulation of FOXOs and gluconeogenesis may contribute to the therapeutic properties of this drug. Further investigation of this signalling response might illuminate novel pharmacological strategies for the treatment of age-related diseases.

Insulin resistance is a characteristic of type 2 diabetes and is a major independent risk factor for progression to the disease. In particular, insulin resistance associates with increased body fat and almost certainly contributes to the dramatic increase in risk of type 2 diabetes associated with obesity. Therefore, in order to design truly effective insulin sensitising agents, targeted at the mechanism of disease development, we aimed to generate an obesity-related insulin resistant cell model. Rat hepatoma cells were grown in the presence of serum isolated from obese rodents or obese human volunteers, and the insulin sensitivity of the cells monitored over time by measuring a well-characterised insulin regulated gene promoter. Higher insulin concentrations were required to fully repress the gene in the cells grown in obese rodent serum compared with those grown in serum from lean rodents (almost a 10-fold shift in insulin sensitivity). This was reversed by restoration of normal growth medium, while the insulin resistance was prevented by pioglitazone or metformin. Meanwhile, growth of cells in serum collected from obese human volunteers with diabetes also reduced the insulin sensitivity of the rat cells. No clinical marker predicted the degree of insulin resistance that was generated by the human serum. We have developed a novel insulin resistant cell model for the study of the molecular development of obesity-linked insulin resistance, screen for compounds to overcome obesity-related insulin resistance and potentially search for novel serum biomarkers of insulin resistance., (Copyright (c) 2010 Elsevier Inc. All rights reserved.)

Objective: To investigate the relationship between the number of outpatient appointments made; the distance traveled to attend these and the proportion of these appointments missed., Design: Retrospective Cohort Study., Setting: Community Paediatrics., Participants: Eighteen pre-school children on the Special Needs Register., Results: With an increase in the number of appointments made and the distances involved in attending these, the number of missed appointments tends to increase., Conclusions: We need to educate parents as to the importance of follow-up, include families in decision making about appointments and rationalize the number of appointments made.

Insulin resistance is a recognized feature of PCOS (polycystic ovary syndrome). However, the molecular reason(s) underlying this reduced cellular insulin sensitivity is not clear. The present study compares the major insulin signalling pathways in skeletal muscle isolated from PCOS and controls. We measured whole-body insulin sensitivity and insulin signalling in skeletal muscle biopsies taken before and after acute exposure to hyperinsulinaemia in nine women diagnosed with PCOS and seven controls. We examined the expression, basal activity and response to in vivo insulin stimulation of three signalling molecules within these human muscle samples, namely IRS-1 (insulin receptor substrate-1), PKB (protein kinase B) and ERK (extracellular-signal-regulated kinase) 1/2. There was no significant difference in the expression, basal activity or activation of IRS-1 or PKB between PCOS and control subjects. However, there was a severe attenuation of insulin stimulation of the ERK pathway in muscle from all but two of the women with PCOS (the two most obese), and an accompanying trend towards higher basal phosphorylation of ERK1/2 in PCOS. These results are striking in that the metabolic actions of insulin are widely believed to require the IRS-1/PKB pathway rather than ERK, and the former has been reported as defective in some previous PCOS studies. Most importantly, the molecular defect identified was independent of adiposity. The altered response of ERK to insulin in PCOS was the most obvious signalling defect associated with insulin resistance in muscle from these patients.

PDK1 activates a group of kinases, including protein kinase B (PKB)/Akt, p70 ribosomal S6 kinase (S6K), and serum and glucocorticoid-induced protein kinase (SGK), that mediate many of the effects of insulin as well as other agonists. PDK1 interacts with phosphoinositides through a pleckstrin homology (PH) domain. To study the role of this interaction, we generated knock-in mice expressing a mutant of PDK1 incapable of binding phosphoinositides. The knock-in mice are significantly small, insulin resistant, and hyperinsulinemic. Activation of PKB is markedly reduced in knock-in mice as a result of lower phosphorylation of PKB at Thr308, the residue phosphorylated by PDK1. This results in the inhibition of the downstream mTOR complex 1 and S6K1 signaling pathways. In contrast, activation of SGK1 or p90 ribosomal S6 kinase or stimulation of S6K1 induced by feeding is unaffected by the PDK1 PH domain mutation. These observations establish the importance of the PDK1-phosphoinositide interaction in enabling PKB to be efficiently activated with an animal model. Our findings reveal how reduced activation of PKB isoforms impinges on downstream signaling pathways, causing diminution of size as well as insulin resistance.

Objective: Abnormal expression of the hepatic gluconeogenic genes (glucose-6-phosphatase [G6Pase] and PEPCK) contributes to hyperglycemia. These genes are repressed by insulin, but this process is defective in diabetic subjects. Protein kinase B (PKB) is implicated in this action of insulin. An inhibitor of PKB, Akt inhibitor (Akti)-1/2, was recently reported; however, the specificity and efficacy against insulin-induced PKB was not reported. Our aim was to characterize the specificity and efficacy of Akti-1/2 in cells exposed to insulin and then establish whether inhibition of PKB is sufficient to prevent regulation of hepatic gene expression by insulin., Research Design and Methods: Akti-1/2 was assayed against 70 kinases in vitro and its ability to block PKB activation in cells exposed to insulin fully characterized., Results: Akti-1/2 exhibits high selectivity toward PKBalpha and PKBbeta. Complete inhibition of PKB activity is achieved in liver cells incubated with 1-10 mumol/l Akti-1/2, and this blocks insulin regulation of PEPCK and G6Pase expression. Our data demonstrate that only 5-10% of maximal insulin-induced PKB is required to fully repress PEPCK and G6Pase expression. Finally, we demonstrate reduced insulin sensitivity of these gene promoters in cells exposed to submaximal concentrations of Akti-1/2; however, full repression of the genes can still be achieved by high concentrations of insulin., Conclusions: This work establishes the requirement for PKB activity in the insulin regulation of PEPCK, G6Pase, and a third insulin-regulated gene, IGF-binding protein-1 (IGFBP1); suggests a high degree of functional reserve; and identifies Akti-1/2 as a useful tool to delineate PKB function in the liver.

Variation in the calpain 10 gene has been reported to increase susceptibility to type 2 diabetes. Part of this susceptibility appears to be mediated by a decrease in whole body insulin sensitivity. As skeletal muscle is the primary tissue site of the peripheral insulin resistance in type 2 diabetes, the aim of this study was to use a human skeletal muscle cell culture system to explore the effects of calpain inhibition on insulin action. Calpain 10 mRNA and protein expression was examined in cultured myoblasts, myotubes, and whole skeletal muscle from non-diabetic subjects using RT-PCR and Western blotting. Changes in insulin-stimulated glucose uptake and glycogen synthesis in response to the calpain inhibitors ALLN and ALLM were measured. Calpain 10 expression was confirmed in cultured human myoblasts, myotubes, and native skeletal muscle. Insulin-stimulated glucose uptake was significantly decreased following preincubation with ALLN [404+/-40 vs 505+/-55 (mean+/-SEM)pmol/mg/min; with vs without ALLN: p = 0.04] and ALLM [455+/-38 vs 550+/-50 pmol/mg/min; with vs without ALLM: p = 0.025] in day 7 fused myotubes, but not in myoblasts. Neither ALLN nor ALLM affected insulin-stimulated glycogen synthesis in myoblasts or myotubes. These studies confirm calpain 10 expression in cultured human muscle cells and support a role for calpains in insulin-stimulated glucose uptake in human skeletal muscle cells that may be relevant to the pathogenesis of the peripheral insulin resistance in type 2 diabetes.

The transcription factor sterol regulatory element binding protein (SREBP)-1c is intimately involved in the regulation of lipid and glucose metabolism. To investigate whether mutations in this gene might contribute to insulin resistance, we screened the exons encoding the aminoterminal transcriptional activation domain in a cohort of 85 unrelated human subjects with severe insulin resistance. Two missense mutations (P87L and P416A) were found in single affected patients but not in 47 control subjects. However, these variants were indistinguishable from the wild-type in their ability to bind DNA or to transactivate an SREBP-1 responsive promoter construct. We also identified a common intronic single nucleotide polymorphism (C/T) located between exon 18c and 19c. In a case-control study of 517 U.K. Caucasian case subjects and 517 age- and sex-matched control subjects, the T-allele at this locus was significantly associated with type 2 diabetes in men (odds ratio = 1.42 [1.11-1.82], P = 0.005) but not women. In a separate population-based study of 1,100 Caucasians, carriers of the T-allele showed significantly higher levels of total and LDL cholesterol (P < 0.05) compared with wild-type individuals. In summary, we have conducted the first study of the SREBP-1c gene as a candidate for human insulin resistance. Although the rare mutations identified were functionally silent in the assays used, we obtained some evidence, which requires conformation in other populations, that a common variant in the SREBP-1c gene might influence diabetes risk and plasma cholesterol level.

Familial partial lipodystrophy-Dunnigan variety (FPLD) is an autosomal dominant form of lipodystrophy resulting in a loss of sc fat from the trunk and limbs with retention of fat in the visceral depots, face, and neck. Specific point mutations in the gene encoding the nuclear lamina proteins, lamins A and C, have been established to cause this syndrome. We undertook studies to determine which members of the lamin family were expressed in human fat cells, to examine the effect of differentiation state on lamin A and C expression in human preadipocytes, and to test the hypothesis that regional variation in lamin A/C expression might underlie the stereotyped anatomical pattern of FPLD. Lamins A, C, and B1, but not B2, were expressed in sc mature human adipocytes. Subcutaneous preadipocytes expressed all four lamins, with lamin A and C expression increasing with ex vivo differentiation. Consistent with previously reported resistance to ex vivo differentiation, omental preadipocytes did not show an increase in lamin A or C mRNA under these conditions. Lamin A/C mRNA levels were similar in isolated mature adipocytes and preadipocytes from omental, sc, and neck sites. However, lamin C was consistently lower, and the ratio of lamin A/C mRNA was higher in sc mature adipocytes compared with omental mature adipocytes. We conclude that the depot-specific pattern of lamin A/C expression does not provide clues to the mechanism of FPLD. Nonetheless, these studies provide new information regarding the expression of lamin isoforms in normal human adipose cells, which will inform future studies of the molecular pathogenesis of FPLD.

The "rediscovery" of poverty, as echoed in concepts of social inequality, has contributed to the goal of eliminating racial/ethnic and social class disparities in the United States. This commentary focuses on what we know about the pressing health care needs and issues relevant to Latino children and families and how extant knowledge can be linked to priority policy recommendations to ensure the inclusion of Latino health issues in the national discourse. A systematic review of the literature on Latino children and of expert opinion revealed 4 evidence-based themes focused on poverty: economic factors, family and community resources, health system factors, and pitfalls in Latino subgroup data collection. Consensus was found on 4 priority policy recommendations: (1) reduce poverty and increase access to health care coverage, (2) increase funding in targeted primary and preventive health care services, (3) provide funds needed to fully implement relevant health legislation, and (4) improve measurement and quality of data collection. If these recommendations are not instituted, the goals of Healthy People 2010 will not be achieved for the Latino population.

Faciogenital dysplasia (FGDY), also known as Aarskog-Scott syndrome, is an X-linked developmental disorder characterized by disproportionately short stature and by facial, skeletal, and urogenital anomalies. Molecular genetic analyses mapped FGDY to chromosome Xp11.21. To clone this gene, YAC clones spanning an FGDY-specific translocation breakpoint were isolated. An isolated cDNA, FGD1, is disrupted by the breakpoint, and FGD1 mutations cosegregate with the disease. FGD1 codes for a 961 amino acid protein that has strong homology to Rho/Rac guanine nucleotide exchange factors (GEFs), contains a cysteine-rich zinc finger-like region, and, like the RasGEF mSos, contains two potential SH3-binding sites. These results provide compelling evidence that FGD1 is responsible for FGDY and suggest that FGD1 is a Rho/RacGEF involved in mammalian development.