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1.
Neuron ; 106(6): 992-1008.e9, 2020 06 17.
Article in English | MEDLINE | ID: mdl-32320644

ABSTRACT

Astrocytes play essential roles in brain function by supporting synaptic connectivity and associated circuits. How these roles are regulated by transcription factors is unknown. Moreover, there is emerging evidence that astrocytes exhibit regional heterogeneity, and the mechanisms controlling this diversity remain nascent. Here, we show that conditional deletion of the transcription factor nuclear factor I-A (NFIA) in astrocytes in the adult brain results in region-specific alterations in morphology and physiology that are mediated by selective DNA binding. Disruptions in astrocyte function following loss of NFIA are most pronounced in the hippocampus, manifested by impaired interactions with neurons, coupled with diminution of learning and memory behaviors. These changes in hippocampal astrocytes did not affect basal neuronal properties but specifically inhibited synaptic plasticity, which is regulated by NFIA in astrocytes through calcium-dependent mechanisms. Together, our studies reveal region-specific transcriptional dependencies for astrocytes and identify astrocytic NFIA as a key transcriptional regulator of hippocampal circuits.


Subject(s)
Astrocytes/metabolism , Brain/metabolism , Calcium/metabolism , Gene Expression Regulation , Learning/physiology , NFI Transcription Factors/genetics , Animals , Astrocytes/physiology , Brain/cytology , Brain/physiopathology , Brain Stem/cytology , Brain Stem/metabolism , Brain Stem/physiopathology , CA1 Region, Hippocampal/cytology , CA1 Region, Hippocampal/metabolism , CA1 Region, Hippocampal/physiopathology , Hippocampus/cytology , Hippocampus/metabolism , Hippocampus/physiopathology , Long-Term Potentiation/physiology , Memory/physiology , Mice , Mice, Knockout , Neural Pathways , Neuronal Plasticity , Neurons , Olfactory Bulb/cytology , Olfactory Bulb/metabolism , Olfactory Bulb/physiopathology , Patch-Clamp Techniques , Prefrontal Cortex/cytology , Prefrontal Cortex/metabolism , Prefrontal Cortex/physiopathology , Spatial Memory/physiology
2.
Int Breastfeed J ; 15: 1, 2020.
Article in English | MEDLINE | ID: mdl-31921327

ABSTRACT

Background: Breastfeeding is a critical, evidence-based intervention that addresses malnutrition, improves early childhood development outcomes, and influences long-term maternal and infant health by reducing the non-communicable disease risk. Scaling up breastfeeding is an indisputably strong action countries can take to prevent suboptimal maternal and infant health outcomes. The Becoming Breastfeeding Friendly (BBF) initiative assists countries with scaling up breastfeeding policy and programs. BBF has been successfully implemented within Latin America, Africa, Europe and South-East Asian regions. This study assessed its application in Samoa. Methods: In 2018, BBF was implemented in Samoa by a 20 member committee of breastfeeding experts who participated in collecting and utilizing national level data to score the degree of friendliness of Samoa's breastfeeding environment, identify gaps, and propose policy recommendations to address those gaps. This eight-month process resulted in a public event where priority recommendations were widely disseminated to decision makers and actions agreed upon. Results: The total BBF Index score for Samoa was 1.6 out of 3.0, indicating a moderate breastfeeding friendly environment for scaling up policies and programs that protect, promote, and support breastfeeding. Gear total scores indicated that seven of the eight gears were moderately strong within Samoa, while the eighth gear, funding and resources, was weakest in strength. Six prioritized recommendations emerged: 1) development and implementation of a National Breastfeeding Policy and Strategic Action Plan; 2) strengthening monitoring and evaluation of all breastfeeding activities; 3) ratifying the International Labour Organization's Maternity Protection Convention 2000 (No 183); 4) identifying high-level advocates to champion and serve as role models for breastfeeding; 5) creation of a national budget line for breastfeeding activities; and 6) hiring of a national breastfeeding coordinator and trainer. Decision makers demonstrated commitment by signing the breastfeeding policy for hospitals ahead of the BBF dissemination meeting and electing to move forward with establishing lactation rooms within government ministries. Conclusion: Implementation of BBF in Samoa yielded important policy recommendations that will address current gaps in national level breastfeeding support. The BBF consultation process can be successfully applied to other countries within the Western Pacific region in order to strengthen their breastfeeding programs.


Subject(s)
Breast Feeding , Capacity Building , Health Plan Implementation/organization & administration , Health Promotion/organization & administration , Postnatal Care/organization & administration , Adult , Female , Health Policy , Health Promotion/methods , Humans , Infant , Infant, Newborn , Male , Postnatal Care/methods , Pregnancy , Program Evaluation , Samoa , Young Adult
3.
Nature ; 578(7793): 166-171, 2020 02.
Article in English | MEDLINE | ID: mdl-31996845

ABSTRACT

Glioblastoma is a universally lethal form of brain cancer that exhibits an array of pathophysiological phenotypes, many of which are mediated by interactions with the neuronal microenvironment1,2. Recent studies have shown that increases in neuronal activity have an important role in the proliferation and progression of glioblastoma3,4. Whether there is reciprocal crosstalk between glioblastoma and neurons remains poorly defined, as the mechanisms that underlie how these tumours remodel the neuronal milieu towards increased activity are unknown. Here, using a native mouse model of glioblastoma, we develop a high-throughput in vivo screening platform and discover several driver variants of PIK3CA. We show that tumours driven by these variants have divergent molecular properties that manifest in selective initiation of brain hyperexcitability and remodelling of the synaptic constituency. Furthermore, secreted members of the glypican (GPC) family are selectively expressed in these tumours, and GPC3 drives gliomagenesis and hyperexcitability. Together, our studies illustrate the importance of functionally interrogating diverse tumour phenotypes driven by individual, yet related, variants and reveal how glioblastoma alters the neuronal microenvironment.


Subject(s)
Brain Neoplasms/enzymology , Class I Phosphatidylinositol 3-Kinases/metabolism , Glioblastoma/enzymology , Animals , Brain Neoplasms/pathology , Carcinogenesis/genetics , Carcinogenesis/metabolism , Class I Phosphatidylinositol 3-Kinases/chemistry , Class I Phosphatidylinositol 3-Kinases/genetics , Disease Models, Animal , Glioblastoma/pathology , Glypicans/metabolism , Mice
4.
Biochem Biophys Rep ; 18: 100630, 2019 Jul.
Article in English | MEDLINE | ID: mdl-30984882

ABSTRACT

The human hCLCA1 gene is a member of the CLCA gene family that has a well-documented role in inflammatory airway diseases. Previously, we demonstrated that secreted hCLCA1 plays a role in regulating the innate immune response by activating airway macrophages. However, the mechanism of this regulation remains unclear. In this present study, recombinant proteins containing different hCLCA1 domains are expressed to determine the specific hCLCA1 domain(s) responsible for macrophage activation. Specifically, hCLCA1 constructs containing the hydrolase domain (HYD), the von Willebrand Factor Type A (VWA) domain, and the fibronectin type III (FN3) domain were heterologously expressed and affinity purified through fast protein liquid chromatography. Circular dichroism spectroscopy revealed that the purified hCLCA1 constructs exhibited secondary structure consistent with folded proteins. The VWA domain clearly demonstrated an ability to activate macrophages, inducing an increase in both IL-1ß mRNA and protein expression. This activation was associated with the activation of MAPKs and NF-κB pathways, identifying potential mechanistic pathways by which hCLCA1's VWA domain exerts its signaling effect. Altogether, this work identifies a domain with signaling function within hCLCA1, providing a specific target to one of the most highly induced gene products of airway inflammatory disease.

5.
Health Syst Reform ; 5(1): 78-82, 2019.
Article in English | MEDLINE | ID: mdl-30924751

ABSTRACT

The increasing prevalence of NCDs such as cardio-vascular diseases, diabetes and kidney failure represents a threat to sustainable development in Samoa. The aim of this commentary is to describe the important role played by women in the community in relation to public health and to detail the lessons learnt and results of a community-based NCD prevention and management package that utilizes the strengths of community engagement at primary care level to accelerate progress towards UHC. The impetus of reforms in Samoa is to strengthen community-based care and rebuild its foundation-Primary Health Care (PHC). In doing so, the government is reinvigorating the role of women's village committees in identifying and referring people with high risks factors for non-communicable diseases. In 2015, an attempt to reinvigorate the role of Komiti Tumama in health was undertaken to address the high burden of non-communicable diseases. The government together with WHO launched a demonstration project, "NCD early detection and self-management through community participation (PEN Fa'a Samoa)", which aimed to address key issues on NCDs through an approach of contextualizing universal health coverage. Preliminary results of the program implementation are positive. PEN Fa'a Samoa achieved a high level of population screening coverage in the demonstration villages, in which the women's committee representatives played a key role. Samoa has shown in this example how such action can strengthen its health system, by utilizing critical human resources at a community level, which have proven to be essential to support the functioning of health services.


Subject(s)
Community Participation/methods , Health Plan Implementation/methods , Primary Health Care/methods , Self-Help Groups , Universal Health Insurance , Adult , Female , Gender Identity , Humans , Noncommunicable Diseases/epidemiology , Samoa/epidemiology , Sustainable Development
6.
J Biol Chem ; 294(15): 6142-6156, 2019 04 12.
Article in English | MEDLINE | ID: mdl-30770467

ABSTRACT

In plants, strict regulation of stomatal pores is critical for modulation of CO2 fixation and transpiration. Under certain abiotic and biotic stressors, pore closure is initiated through anionic flux, with calcium (Ca2+) playing a central role. The aluminum-activated malate transporter 12 (ALMT12) is a malate-activated, voltage-dependent member of the aluminum-activated malate transporter family that has been implicated in anionic flux from guard cells controlling the stomatal aperture. Herein, we report the characterization of the regulatory mechanisms mediating channel activities of an ALMT from the grass Brachypodium distachyon (BdALMT12) that has the highest sequence identity to Arabidopsis thaliana ALMT12. Electrophysiological studies in a heterologous cell system confirmed that this channel is malate- and voltage-dependent. However, this was shown to be true only in the presence of Ca2+ Although a general kinase inhibitor increased the current density of BdALMT12, a calmodulin (CaM) inhibitor reduced the Ca2+-dependent channel activation. We investigated the physiological relevance of the CaM-based regulation in planta, where stomatal closure, induced by exogenous Ca2+ ionophore and malate, was shown to be inhibited by exogenous application of a CaM inhibitor. Subsequent analyses revealed that the double substitutions R335A/R338A and R335A/K342A, within a predicted BdALMT12 CaM-binding domain (CBD), also decreased the channels' ability to activate. Using isothermal titration calorimetry and CBD-mimetic peptides, as well as CaM-agarose affinity pulldown of full-length recombinant BdALMT12, we confirmed the physical interaction between the CBD and CaM. Together, these findings support a co-regulatory mechanism of BdALMT12 activation by malate, and Ca2+/CaM, emphasizing that a complex regulatory network modulates BdALMT12 activity.


Subject(s)
Brachypodium , Calcium , Calmodulin , Organic Anion Transporters , Plant Proteins , Plant Stomata , Amino Acid Substitution , Brachypodium/chemistry , Brachypodium/genetics , Brachypodium/metabolism , Calcium/chemistry , Calcium/metabolism , Calmodulin/chemistry , Calmodulin/genetics , Calmodulin/metabolism , Ion Channel Gating/physiology , Malates/chemistry , Malates/metabolism , Mutation, Missense , Organic Anion Transporters/chemistry , Organic Anion Transporters/genetics , Organic Anion Transporters/metabolism , Plant Proteins/chemistry , Plant Proteins/genetics , Plant Proteins/metabolism , Plant Stomata/chemistry , Plant Stomata/genetics , Plant Stomata/metabolism
7.
Elife ; 62017 10 20.
Article in English | MEDLINE | ID: mdl-29053101

ABSTRACT

Von Hippel-Landau (VHL) protein is a potent tumor suppressor regulating numerous pathways that drive cancer, but mutations in VHL are restricted to limited subsets of malignancies. Here we identified a novel mechanism for VHL suppression in tumors that do not have inactivating mutations. Using developmental processes to uncover new pathways contributing to tumorigenesis, we found that Daam2 promotes glioma formation. Protein expression screening identified an inverse correlation between Daam2 and VHL expression across a host of cancers, including glioma. These in silico insights guided corroborating functional studies, which revealed that Daam2 promotes tumorigenesis by suppressing VHL expression. Furthermore, biochemical analyses demonstrate that Daam2 associates with VHL and facilitates its ubiquitination and degradation. Together, these studies are the first to define an upstream mechanism regulating VHL suppression in cancer and describe the role of Daam2 in tumorigenesis.


Subject(s)
Carcinogenesis , Glioma/physiopathology , Intracellular Signaling Peptides and Proteins/metabolism , Von Hippel-Lindau Tumor Suppressor Protein/metabolism , Humans , Microfilament Proteins , Protein Binding , Proteolysis , Ubiquitination , rho GTP-Binding Proteins
8.
BMC Vet Res ; 12(1): 121, 2016 Jun 21.
Article in English | MEDLINE | ID: mdl-27329127

ABSTRACT

BACKGROUND: Congenital stationary night-blindness (CSNB) is a recessive autosomal defect in low-light vision in Appaloosa and other horse breeds. This condition has been mapped by linkage analysis to a gene coding for the Transient Receptor Potential cation channel Member 1 (TRPM1). TRPM1 is normally expressed in the ON-bipolar cells of the inner nuclear layer of the retina. Down-regulation of TRPM1 expression in CSNB results from a transposon-like insertion in intron 1 of the TRPM1 gene. Stop transcription signals in this transposon significantly reduce TRPM1 primary transcript levels in CSNB horses. This study describes additional contributions by a second mutation of the TRPM1 gene, the ECA1 108,249,293 C > T SNP, to down-regulation of transcription of the TRPM1 gene in night-blind horses. This TRPM1 SNP introduces a consensus binding site for neuro-oncological ventral antigen 1 (Nova-1) protein in the primary transcript. Nova-1 binding disrupts normal splicing signals, producing unstable, non-functional mRNA transcripts. RESULTS: Retinal bipolar cells express both TRPM1 and Nova-1 proteins. In vitro addition of Nova-1 protein retards electrophoretic migration of TRPM1 RNA containing the ECA1 108,249,293 C > T SNP. Up-regulating Nova-1 expression in primary cultures of choroidal melanocytes carrying the intron 11 SNP caused an average log 2-fold reduction of ~6 (64-fold) of TRPM1 mRNA expression. CONCLUSIONS: These finding suggest that the equine TRPM1 SNP can act independently to reduce survival of TRPM1 mRNA escaping the intron 1 transcriptional stop signals in CSNB horses. Coexistence and co-inheritance of two independent TRPM1 mutations across 1000 equine generations suggests a selective advantage for the apparently deleterious CSNB trait.


Subject(s)
Eye Diseases, Hereditary/veterinary , Genetic Diseases, X-Linked/veterinary , Horse Diseases/genetics , Myopia/veterinary , Night Blindness/veterinary , Polymorphism, Single Nucleotide , TRPM Cation Channels/genetics , Animals , Binding Sites , Cells, Cultured , Exons , Eye Diseases, Hereditary/genetics , Genetic Diseases, X-Linked/genetics , Horses , Myopia/genetics , Nerve Tissue Proteins/genetics , Neuro-Oncological Ventral Antigen , Night Blindness/genetics , RNA/metabolism , RNA-Binding Proteins/genetics
9.
J Neuroinflammation ; 12: 37, 2015 Feb 25.
Article in English | MEDLINE | ID: mdl-25890242

ABSTRACT

BACKGROUND: Lipopolysaccharide (LPS)-mediated sickness behaviour is known to be a result of increased inflammatory cytokines in the brain. Inflammatory cytokines have been shown to mediate increases in brain excitation by loss of GABAA-mediated inhibition through receptor internalization or inactivation. Inflammatory pathways, reactive oxygen species and stress are also known to increase monoamine oxidase-A (MAO-A) and acetylcholinesterase (ACh-E) activity. Given that neuromodulator actions on neural circuits largely depend on inhibitory pathways and are sensitive to alteration in corresponding catalytic enzyme activities, we assessed the impact of systemic LPS on neuromodulator-mediated shaping of a simple cortical network. METHODS: Extracellular field recordings of evoked postsynaptic potentials in adult mouse somatosensory cortical slices were used to evaluate effects of a single systemic LPS challenge on neuromodulator function 1 week later. Neuromodulators were administered transiently as a bolus (100 µl) to the bath perfusate immediately upstream of the recording site to mimic phasic release of neuromodulators and enable assessment of response temporal dynamics. RESULTS: Systemic LPS administration resulted in loss of both spontaneous and evoked inhibition as well as alterations in the temporal dynamics of neuromodulator effects on a paired-pulse paradigm. The effects on neuromodulator temporal dynamics were sensitive to the Monoamine oxidase-A (MAO-A) antagonist clorgyline (for norepinephrine and serotonin) and the ACh-E inhibitor donepezil (for acetylcholine). This is consistent with significant increases in total MAO and ACh-E activity found in hemi-brain samples from the LPS-treated group, supporting the notion that systemic LPS administration may lead to longer-lasting changes in inhibitory network function and enzyme (MAO/ACh-E) activity responsible for reduced neuromodulator actions. CONCLUSIONS: Given the significant role of neuromodulators in behavioural state and cognitive processes, it is possible that an inflammatory-mediated change in neuromodulator action plays a role in LPS-induced cognitive effects and could help define the link between infection and neuropsychiatric/degenerative conditions.


Subject(s)
Acetylcholinesterase/metabolism , Cerebral Cortex , Lipopolysaccharides/pharmacology , Monoamine Oxidase/metabolism , Neurons/drug effects , Acetylcholine/pharmacology , Action Potentials/drug effects , Animals , Bicuculline/pharmacology , Biogenic Monoamines/pharmacology , Cerebral Cortex/cytology , Cerebral Cortex/drug effects , Cerebral Cortex/metabolism , Dose-Response Relationship, Drug , Electric Stimulation , GABA-A Receptor Antagonists/pharmacology , Hindlimb Suspension/methods , In Vitro Techniques , Male , Mice , Mice, Inbred C57BL , Nitric Oxide/metabolism , Reaction Time/drug effects , Signal Transduction/drug effects , Time Factors
10.
BMC Pregnancy Childbirth ; 15: 10, 2015 Feb 03.
Article in English | MEDLINE | ID: mdl-25643752

ABSTRACT

BACKGROUND: As obesity has increased worldwide, so have levels of obesity during pregnancy and excess gestational weight gain (GWG). The aim of this paper was to describe GWG among American Samoan women and examine the association between GWG and four adverse pregnancy and infant outcomes: cesarean delivery, small- and large-for-gestational age (SGA/LGA), and infant overweight/obesity. METHODS: Data were extracted from prenatal care records of 632 Samoan women. Mixed-effects growth models were used to produce individual weight-for-gestational week curves from which second and third trimester weight gain was estimated. Binary logistic regression was used to examine associations between GWG and the outcomes of interest. RESULTS: Most women were overweight/obese in early pregnancy (86%) and 78% exceeded the Institute of Medicine GWG guidelines. Greater GWG in the second trimester and early pregnancy weight were independently associated with increased odds of a c-section (OR 1.40 [95% CI: 1.08, 1.83]) and OR 1.51 [95% CI: 1.17, 1.95], respectively). Risk of delivering a LGA infant increased with greater third trimester weight gain and higher early pregnancy weight, while second trimester weight gain was negatively associated with SGA. Risk of infant overweight/obesity at 12 months increased with early pregnancy weight (OR: 1.23 [95% CI: 1.01, 1.51]) and infant birthweight. CONCLUSIONS: The high levels of pregnancy obesity and excessive GWG in American Samoa suggest that it is important for physicians to encourage women into prenatal care early and begin education about appropriate GWG and the potential risks of excess weight gain for both the mother and baby.


Subject(s)
Birth Weight , Cesarean Section/statistics & numerical data , Fetal Macrosomia/epidemiology , Gestational Age , Obesity/epidemiology , Pregnancy Complications/epidemiology , Weight Gain , Adult , American Samoa/epidemiology , Cohort Studies , Delivery, Obstetric/statistics & numerical data , Female , Humans , Infant, Newborn , Infant, Small for Gestational Age , Male , Odds Ratio , Overweight/epidemiology , Pregnancy , Retrospective Studies , Young Adult
11.
Am J Physiol Regul Integr Comp Physiol ; 307(7): R802-16, 2014 Oct 01.
Article in English | MEDLINE | ID: mdl-25080498

ABSTRACT

The objectives of this study were to determine the effect of an increase in diet fermentability on 1) the rate and extent to which short-chain fatty acid (SCFA) absorption pathways adapt relative to changes in Na(+) transport, 2) the epithelial surface area (SA), and 3) the barrier function of the bovine ruminal epithelium. Twenty-five Holstein steer calves were assigned to either the control diet (CON; 91.5% hay and 8.5% supplement) or a moderately fermentable diet (50% hay; 41.5% barley grain (G), and 8.5% supplement) fed for 3 (G3), 7 (G7), 14 (G14), or 21 days (G21). All calves were fed at 2.25% body weight at 0800. Calves were killed (at 1000), and ruminal tissue was collected to determine the rate and pathway of SCFA transport, Na(+) transport and barrier function in Ussing chambers. Tissue was also collected for SA measurement and gene expression. Mean reticular pH decreased from 6.90 for CON to 6.59 for G7 and then increased (quadratic P < 0.001). While effective SA of the ruminal epithelium was not affected (P > 0.10) by dietary treatment, the net Na(+) flux increased by 125% within 7 days (quadratic P = 0.016). Total acetate and butyrate flux increased from CON to G21, where passive diffusion was the primary SCFA absorption pathway affected. Increased mannitol flux, tissue conductance, and tendencies for increased expression of IL-1ß and TLR2 indicated reduced rumen epithelium barrier function. This study indicates that an increase in diet fermentability acutely increases Na(+) and SCFA absorption in the absence of increased SA, but reduces barrier function.


Subject(s)
Epithelium/metabolism , Fatty Acids, Volatile/metabolism , Sodium/metabolism , Adaptation, Physiological , Animal Feed/analysis , Animal Nutritional Physiological Phenomena/physiology , Animals , Biological Transport/physiology , Cattle , Diet/veterinary , Dietary Supplements , Rumen/physiology , Time Factors
12.
Eur J Neurosci ; 40(6): 2859-66, 2014 Sep.
Article in English | MEDLINE | ID: mdl-24964151

ABSTRACT

Glioblastoma (GBM) is by far the most common and most malignant primary adult brain tumor (World Health Organization grade IV), containing a fraction of stem-like cells that are highly tumorigenic and multipotent. Recent research has revealed that GBM stem-like cells play important roles in GBM pathogenesis. GBM is thought to arise from genetic anomalies in glial development. Over the past decade, a wide range of studies have shown that several signaling pathways involved in neural development, including basic helix-loop-helix, Wnt-ß-catenin, bone morphogenetic proteins-Smads, epidermal growth factor-epidermal growth factor receptor, and Notch, play important roles in GBM pathogenesis. In this review, we highlight the significance of these pathways in the context of developing treatments for GBM. Extrapolating knowledge and concepts from neural development will have significant implications for designing better strategies with which to treat GBM.


Subject(s)
Brain Neoplasms/physiopathology , Brain Neoplasms/therapy , Glioblastoma/physiopathology , Glioblastoma/therapy , Animals , Brain/growth & development , Brain/physiopathology , Humans , Neoplastic Stem Cells/physiology , Neural Stem Cells/physiology , Signal Transduction
13.
Matern Child Health J ; 18(10): 2284-92, 2014 Dec.
Article in English | MEDLINE | ID: mdl-24045912

ABSTRACT

The objective of this study is to describe the utilization of prenatal care in American Samoan women and to identify socio-demographic predictors of inadequate prenatal care utilization. Using data from prenatal clinic records, women (n = 692) were categorized according to the adequacy of prenatal care utilization index as having received adequate plus, adequate, intermediate or inadequate prenatal care during their pregnancy. Categorical socio-demographic predictors of the timing of initiation of prenatal care (week of gestation) and the adequacy of received services were identified using one way analysis of variance and independent samples t tests. Between 2001 and 2008 85.4 % of women received inadequate prenatal care. Parity (P = 0.02), maternal unemployment (P = 0.03), and both parents being unemployed (P = 0.03) were negatively associated with the timing of prenatal care initiation. Giving birth in 2007-2008, after a prenatal care incentive scheme had been introduced in the major hospital, was associated with earlier initiation of prenatal care (20.75 vs. 25.12 weeks; P < 0.01) and improved adequacy of received services (95.04 vs. 83.8 %; P = 0.02). The poor prenatal care utilization in American Samoa is a major concern. Improving healthcare accessibility will be key in encouraging women to attend prenatal care. The significant improvements in the adequacy of prenatal care seen in 2007-2008 suggest that the prenatal care incentive program implemented in 2006 may be a very positive step toward addressing issues of prenatal care utilization in this population.


Subject(s)
Attitude to Health , Health Services Accessibility , Prenatal Care/statistics & numerical data , Adolescent , Adult , Age Factors , American Samoa , Female , Humans , Interviews as Topic , Parity , Pregnancy , Primary Health Care , Qualitative Research , Quality of Health Care , Risk Factors , Socioeconomic Factors , Surveys and Questionnaires , Young Adult
14.
PLoS One ; 8(12): e83130, 2013.
Article in English | MEDLINE | ID: mdl-24349445

ABSTRACT

The CLCA gene family produces both secreted and membrane-associated proteins that modulate ion-channel function, drive mucus production and have a poorly understood pleiotropic effect on airway inflammation. The primary up-regulated human CLCA ortholog in airway inflammation is hCLCA1. Here we show that this protein can activate airway macrophages, inducing them to express cytokines and to undertake a pivotal role in airway inflammation. In a U-937 airway macrophage-monocyte cell line, conditioned media from HEK 293 cells heterologously expressing hCLCA1 (with or without fetal bovine serum) increased the levels of pro-inflammatory cytokines (IL-1ß, IL-6, TNF-α and IL-8). This effect was independent of the metalloprotease domain of hCLCA1. Primary porcine alveolar macrophages were similarly activated, demonstrating the effect was not cell line dependent. Similarly, immuno-purified hCLCA1 at physiologically relevant concentration of ~100 pg/mL was able to activate macrophages and induce pro-inflammatory response. This cytokine response increased with higher concentration of immuno-purified hCLCA1. These findings demonstrate the ability of hCLCA1 to function as a signaling molecule and activate macrophages, central regulators of airway inflammation.


Subject(s)
Chloride Channels/metabolism , Macrophage Activation , Macrophages, Alveolar/metabolism , Signal Transduction , Animals , Cattle , Chloride Channels/immunology , Cytokines/biosynthesis , Cytokines/immunology , HEK293 Cells , Humans , Inflammation/immunology , Inflammation/metabolism , Inflammation/pathology , Macrophages, Alveolar/immunology , Macrophages, Alveolar/pathology , Protein Structure, Tertiary , Swine , U937 Cells
15.
Biochem Biophys Res Commun ; 438(4): 581-7, 2013 Sep 06.
Article in English | MEDLINE | ID: mdl-23954634

ABSTRACT

Influenza infects the epithelial cells lining the airways. Normally epithelial cells move solutes through ion channels to create the osmotic drive to hydrate the airways. Viral alteration of this process could explain, in part, the fluid imbalance in the lungs and the resulting pulmonary edema that occurs during severe influenza infections. Using western blot and RT-qPCR, we measured ion channel and cytokine expression in the Calu3 airway cell line after infection with influenza virus (H1N1) for 48 h. We simultaneously measured chloride and potassium channel function by means of a short-circuit current (I(sc)) produced in an Ussing chamber. At a multiplicity of infection (MOI) of 10, viral M1 protein and pro-inflammatory cytokine expression was observed 24h post-infection, despite a lack of measurable change in Isc. However, we observed a decreased secretory response in cAMP- and calcium-induced Isc 48 h post-infection. This correlated with a decrease in CFTR and KCNN4 protein levels. Interestingly, a viral dose of an MOI 0.6 revealed an increased secretory response that correlated with pro-inflammatory cytokine expression. This increased secretory response seemed to be primarily driven through KCNN4. We detected an increase in KCNN4 mRNA and protein, while CFTR function and expression remained unchanged. Furthermore, inhibition of the KCNN4-stimulated I(sc) with TRAM-34, a specific inhibitor, ameliorated the response, implicating KCNN4 as the main driving force behind the secretory phenotype.


Subject(s)
Epithelial Cells/virology , Host-Pathogen Interactions , Influenza A Virus, H1N1 Subtype/physiology , Influenza, Human/metabolism , Intermediate-Conductance Calcium-Activated Potassium Channels/metabolism , Cell Line , Epithelial Cells/metabolism , Humans , Influenza, Human/genetics , Influenza, Human/virology , Intermediate-Conductance Calcium-Activated Potassium Channels/antagonists & inhibitors , Intermediate-Conductance Calcium-Activated Potassium Channels/genetics , Lung/cytology , Lung/virology , RNA, Messenger/genetics , Up-Regulation
16.
Asia Pac J Public Health ; 25(1): 19-31, 2013 Jan.
Article in English | MEDLINE | ID: mdl-22652246

ABSTRACT

The prevalence of cervical and anal human papillomavirus (HPV) and risk factors associated with infections were evaluated in a cross-sectional study of 211 adult women in American Samoa. Overall, 53% of women reported ever having a Pap smear. Cervical and anal HPV was detected in 10% and 16% of women, respectively; 4% of women had concurrent cervical and anal HPV. The most common cervical genotypes were HPV 6, HPV 16, and HPV 53. Cutaneous HPV types were detected in 40% of anal infections. Cervical HPV infection was associated with anal HPV (age-adjusted odds ratio = 3.32, 1.10-10.00). After age adjustment, cervical HPV was associated with being unmarried, postsecondary education, hot running water at home, multiple sexual partners, nulliparity, condom use, and other contraceptive methods. In multivariate analyses, only age remained associated with cervical HPV and anal HPV. Cervical and anal HPV was more prevalent among younger women; only anal HPV was detected in older women.


Subject(s)
Anus Diseases/epidemiology , Papillomavirus Infections/epidemiology , Uterine Cervical Diseases/epidemiology , Adult , Anus Diseases/virology , Cross-Sectional Studies , Female , Humans , Papillomavirus Infections/virology , Prevalence , Risk Factors , Samoa/epidemiology , Uterine Cervical Diseases/virology
17.
Proc Natl Acad Sci U S A ; 109(2): E76-83, 2012 Jan 10.
Article in English | MEDLINE | ID: mdl-22084095

ABSTRACT

Release of substance P (SP) from nociceptive nerve fibers and activation of its receptor neurokinin 1 (NK1) are important effectors in the transmission of pain signals. Nonetheless, the role of SP in muscle pain remains unknown. Here we show that a single i.m. acid injection in mice lacking SP signaling by deletion of the tachykinin precursor 1 (Tac1) gene or coadministration of NK1 receptor antagonists produces long-lasting hyperalgesia rather than the transient hyperalgesia seen in control animals. The inhibitory effect of SP was found exclusively in neurons expressing acid-sensing ion channel 3, where SP enhances M-channel-like potassium currents through the NK1 receptor in a G protein-independent but tyrosine kinase-dependent manner. Furthermore, the SP signaling could alter action potential thresholds and modulate the expression of TTX-resistant sodium currents in medium-sized muscle nociceptors. Thus, i.m. SP mediates an unconventional NK1 receptor signal pathway to inhibit acid activation in muscle nociceptors, resulting in an unexpected antinociceptive effect against chronic mechanical hyperalgesia, here induced by repeated i.m. acid injection.


Subject(s)
Analgesics/metabolism , Chronic Pain/metabolism , Musculoskeletal Pain/metabolism , Receptors, Neurokinin-1/metabolism , Substance P/metabolism , Acid Sensing Ion Channels , Action Potentials/physiology , Animals , Chronic Pain/chemically induced , Electrophysiology , Ganglia, Spinal/metabolism , Gene Deletion , Mice , Mice, Inbred C57BL , Musculoskeletal Pain/chemically induced , Neurokinin A/genetics , Neurokinin-1 Receptor Antagonists , Pain Measurement , Patch-Clamp Techniques , Protein Precursors/deficiency , Protein Precursors/genetics , Sodium Channels/genetics , Tachykinins/deficiency , Tachykinins/genetics
18.
Pituitary ; 10(4): 327-33, 2007.
Article in English | MEDLINE | ID: mdl-17899386

ABSTRACT

Pediatric pituitary diagnosis is complicated by the unique developmental characteristics, secretory patterns and regulation of each pituitary hormone system. Although dynamic test procedures have been described, validation of each procedure is limited and universally agreed diagnostic criteria are not available. Clinical acumen, experience and judgment continue to be primary elements of pituitary diagnosis.


Subject(s)
Endocrinology , Pediatrics , Pituitary Diseases/diagnosis , Child , Humans , Pituitary Diseases/physiopathology
19.
Diabetes Technol Ther ; 8(6): 663-70, 2006 Dec.
Article in English | MEDLINE | ID: mdl-17109598

ABSTRACT

BACKGROUND: This study was designed to test the feasibility and efficacy of continuous subcutaneous insulin infusion (CSII) being instituted within 1 month of diagnosis of type 1 diabetes mellitus (T1DM). METHODS: Twenty-eight consecutive patients with newly diagnosed T1DM with a mean age of 12.1 +/- 6.2 years were placed on CSII, as early as within 1 day of their diagnosis. All accepted CSII when offered it, and none elected to discontinue CSII after follow-up periods of up to 3 years. RESULTS: Hemoglobin A1c levels declined from an initial mean of 10.5 +/- 2.4% to between 6.5% and 7.4% over the next 18 months, at a mean insulin requirement of 0.33 units/kg/day at 3 months, which gradually rose to 0.58 units/kg/day by 18 months. Endogenous insulin secretion, measured by C-peptide values, remained stable during the first 12 months after diagnosis. There was no significant weight gain for the duration of the study (20.7 kg/m(2) vs. a peak of 22.1 kg/m(2) at 12 months, P = 0.54). CONCLUSIONS: The study provided a positive experience with CSII as the initial insulin replacement therapy in newly diagnosed patients with T1DM with excellent clinical outcomes and apparent prolongations of the honeymoon period. It remains to be proven by random patient assignment whether endogenous insulin secretion is better preserved with CSII as an initial ongoing treatment modality and whether long-term complications are reduced by this approach.


Subject(s)
Diabetes Mellitus, Type 1/drug therapy , Insulin Infusion Systems , Insulin/administration & dosage , Adolescent , Adult , Child , Child, Preschool , Diabetes Mellitus, Type 1/diagnosis , Female , Humans , Male , Time Factors
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