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1.
BMJ Open ; 14(2): e078486, 2024 02 02.
Article in English | MEDLINE | ID: mdl-38309754

ABSTRACT

INTRODUCTION: Concerns about falling (CaF) are common in older people and have been associated with avoidance of activities of daily life. Exercise designed to prevent falls can reduce CaF, but the effects are usually short-lived. Cognitive behavioural therapy (CBT) can reduce CaF for longer but is not readily available in the community and unlikely to prevent falls. A multidomain intervention that combines CBT, motivational interviewing and exercise could be the long-term solution to treat CaF and reduce falls in older people with CaF. This paper describes the design of a randomised controlled trial to test the effectiveness of two different 12 week self-managed eHealth programmes to reduce CaF compared with an active control. METHODS: A total of 246 participants (82 per group) aged 65 and over, with substantial concerns about falls or balance will be recruited from the community. They will be randomised into: (1) myCompass-Own Your Balance (OYB) (online CBT programme) intervention or (2) myCompass-OYB plus StandingTall intervention (an eHealth balance exercise programme), both including motivational interviewing and online health education or (3) an active control group (online health education alone). The primary outcome is change in CaF over 12 months from baseline of both intervention groups compared with control. The secondary outcomes at 2, 6 and 12 months include balance confidence, physical activity, habitual daily activity, enjoyment of physical activity, social activity, exercise self-efficacy, rate of falls, falls health literacy, mood, psychological well-being, quality of life, exercise self-efficacy, programme adherence, healthcare use, user experience and attitudes towards the programme. An intention-to-treat analysis will be applied. The healthcare funder's perspective will be adopted for the economic evaluation if appropriate. ETHICS AND DISSEMINATION: Ethical approval was obtained from the South Eastern Sydney Local Health District Human Research Ethics Committee (2019/ETH12840). Results will be disseminated via peer-reviewed journals, local and international conferences, community events and media releases. TRIAL REGISTRATION NUMBER: ACTRN12621000440820.


Subject(s)
Quality of Life , Telemedicine , Humans , Aged , Exercise Therapy/methods , Exercise/psychology , Randomized Controlled Trials as Topic
2.
Clin Physiol Funct Imaging ; 43(5): 365-372, 2023 Sep.
Article in English | MEDLINE | ID: mdl-37190935

ABSTRACT

The pupillary light reflex (PLR) is a method for measuring dynamic responses within the autonomic nervous system, and would have potential value as a point-of-care test in a psychiatry clinic if reproducible results could be obtained in a short period of time. We collected PLR from adult community volunteers and depressed outpatients with the purpose of demonstrating (1) that valid data could be obtained >90% of the time from both the community volunteers and the patients, and (2) that reproducible results could be obtained with repeated measurement over short periods of time. Valid data were captured for 90.3% of 76 participants, allowing for two attempts of the PLR per participant. Success rates were similar for depressed patients and community volunteers. Eighteen of these 76 participants provided repeated paired measurements after 5 and 10 min of dark adaptation, producing high correlations for maximum constriction velocity (MCV) between assay 1 and 2 (Pearson's r = 0.71, p < 0.001), but there was a significant 8% increase in velocity for MCV between assay 1 and 2 (∆ = 0.34 ± 0.59 mm/s, p < 0.05). In contrast, PLR measurements were stable when tested in a separate cohort of 21 additional participants at 10 and 15 min of dark adaptation with an MCV Pearson's correlation of r = 0.84, p < 0.001, with a nonsignificant 1% difference between the two time points. These findings indicate an acceptable rate of collecting valid and reproducible PLR data when contrasting two measurements of PLR after 10 or 15 min of dark adaptation in depressed and suicidal patients.


Subject(s)
Light , Reflex, Pupillary , Adult , Humans , Reflex, Pupillary/physiology , Reproducibility of Results , Volunteers , Outpatients
3.
Health Secur ; 21(2): 156-163, 2023.
Article in English | MEDLINE | ID: mdl-36716272

ABSTRACT

From the Field is a semiregular column that provides insight into the experiences of local, county, or state health professionals on the frontlines of health emergencies. National Association of County and City Health Officials members share the challenges faced and the solutions developed as they prepared for and responded to disasters, epidemics, and other major health issues. The aim of sharing these practical experiences is to provide other public health champions with the information and tools they need to help keep their communities safe even in extreme situations. The COVID-19 pandemic created an extraordinarily high demand for personal protective equipment (PPE). Acute need and supply chain disruptions made hospitals, emergency medical services, and other critical care agencies particularly vulnerable to PPE shortages. In March 2020, King County, Washington, developed computational tools, operating procedures, and data visualizations to fulfill its responsibilities to prioritize, allocate, and distribute scarce PPE equitably and efficiently during a public health emergency. King County distributed over 1.6 million gowns, 22 million gloves, 3.9 million surgical masks, and 1.5 million N95 respirators (among other items) during its PPE distribution mission. An algorithm processed resource requests from the community, with respect to available inventory, emergency allocation policies, prioritization constraints, estimated PPE use rates, agency-specific needs, and other parameters. With these inputs and constraints, the requests were translated into instructions for fulfillment and delivery and several tabular and graphical data visualizations were produced for quality assurance and transparency. Access to timely, relevant, and stable data was a constant challenge, and constraints invariably changed as the emergency response unfolded. King County's PPE distribution mission provides a useful case study in how to develop a scalable and data-driven approach to resource allocation and distribution under emergency response conditions.


Subject(s)
COVID-19 , Humans , COVID-19/prevention & control , Washington , Pandemics/prevention & control , Personal Protective Equipment , Health Personnel
4.
Ecol Evol ; 12(12): e9614, 2022 Dec.
Article in English | MEDLINE | ID: mdl-36523531

ABSTRACT

Habitat divergence among close relatives is a common phenomenon. Studying the mechanisms behind habitat divergence is fundamental to understanding niche partitioning, species diversification, and other evolutionary processes. Recent studies found that soil microbes regulate the abundance and diversity of plant species. However, it remains unclear whether soil microbes can affect the habitat distributions of plants and drive habitat divergence. To fill in this knowledge gap, we investigated whether soil microbes might restrict habitat distributions of closely related oaks (Quercus spp.) in eastern North America. We performed a soil inoculum experiment using two pairs of sister species (i.e., the most closely related species) that show habitat divergence: Quercus alba (local species) vs. Q. michauxii (foreign), and Q. shumardii (local) vs. Q. acerifolia (foreign). To test whether host-specific soil microbes are responsible for habitat restriction, we investigated the impact of local sister live soil (containing soil microbes associated with local sister species) on the survival and growth of local and foreign species. Second, to test whether habitat-specific soil microbes are responsible for habitat restriction, we examined the effect of local habitat live soil (containing soil microbes within local sister's habitats, but not directly associated with local sister species) on the seedlings of local and foreign species. We found that local sister live soil decreased the survival and biomass of foreign species' seedlings while increasing those of local species, suggesting that host-specific soil microbes could potentially mediate habitat exclusion. In contrast, local habitat live soil did not differentially affect the survival or biomass of the local vs. foreign species. Our study indicates that soil microbes associated with one sister species can suppress the recruitment of the other host species, contributing to the habitat partitioning of close relatives. Considering the complex interactions with soil microbes is essential for understanding the habitat distributions of closely related plants.

5.
BMJ Open ; 11(4): e051085, 2021 04 15.
Article in English | MEDLINE | ID: mdl-33858875

ABSTRACT

INTRODUCTION: Falls have a multifactorial aetiology, which may limit the effectiveness of the common approach of exercise as the sole intervention strategy. Multifactorial interventions could be more effective in people at high risk of falling; however, the focus of such interventions has traditionally been quite narrow. This paper describes the design of a randomised controlled trial that will evaluate the effectiveness of an eHealth programme, which addresses cumulative effects of key fall-risk factors across the triad of physical, affective and cognitive functions on falls in older people. METHODS AND ANALYSIS: 518 older people aged 65 years and over with high fall risk, defined as having a history of falls in the past 6 months, self-reported fear of falling or being aged 80 years or over, will be recruited via local advertisements, newsletters and presentations, and randomised to an intervention or health education control group. The intervention comprises balance exercise, cognitive-motor exercise and cognitive-behavioural therapy, with their dosage based on participant's baseline balance, executive function and mood. The primary outcome is the rate of falls in the 12 months after randomisation. Secondary outcomes at 6 and 12 months comprise programme adherence, healthcare use, physical activity, balance and mobility, cognitive function, psychological well-being, quality of life, health literacy and user experience and attitudes towards the programme. Data will be analysed following intention to treat to gauge real-world effectiveness. We will further determine complier averaged causal effects to correct for varying adherence and conduct economic analyses to gain insight into cost-effectiveness and cost-utility. ETHICS AND DISSEMINATION: Ethical approval was obtained from the University of New South Wales (UNSW) Human Research Ethics Committee in December 2017. Outcomes will be disseminated via peer-reviewed articles, conference presentations, community events and media releases. TRIAL REGISTRATION NUMBER: ACTRN12619000540112.


Subject(s)
Quality of Life , Telemedicine , Aged , Aged, 80 and over , Exercise Therapy , Fear , Humans , Randomized Controlled Trials as Topic
6.
Aust J Prim Health ; 27(4): 291-296, 2021 Aug.
Article in English | MEDLINE | ID: mdl-33773606

ABSTRACT

The clinical work of GPs and physiotherapists frequently involves the assessment of patient pain. In this study, we aimed to determine the correlation of patient- and clinician-assessment of severity of pain through quantitative analysis of patient- and clinician-assessed pain scores collected at metropolitan general practice and physiotherapy clinics. Prior to a consultation, 30 patients were asked to complete a short general health survey within which they answered questions regarding current pain and, if in pain, the severity of that pain on the visual analogue scale. Following the consultation, their clinicians were asked questions on their observation of the patients, including whether they observed that their patients were in pain and, if so, how severe on the visual analogue scale. Statistical analysis of these data showed that although there was a correlation between the physiotherapist- and patient-assessed pain scores, there was no correlation between the GP- and patient-assessed pain scores. Accurately establishing the severity of patient pain can be difficult. These results suggest that GPs routinely underestimate the severity of patient pain. If the severity of patient pain is clinically relevant, GPs could improve the accuracy of assessment by asking patients directly about that aspect of pain.


Subject(s)
General Practice , Physical Therapy Modalities , Family Practice , Humans , Pain , Pain Measurement
9.
Glob Chang Biol ; 22(10): 3461-73, 2016 10.
Article in English | MEDLINE | ID: mdl-27252148

ABSTRACT

Cassava is an important dietary component for over 1 billion people, and its ability to yield under drought has led to it being promoted as an important crop for food security under climate change. Despite its known photosynthetic plasticity in response to temperature, little is known about how temperature affects plant toxicity or about interactions between temperature and drought, which is important because cassava tissues contain high levels of toxic cyanogenic glucosides, a major health and food safety concern. In a controlled glasshouse experiment, plants were grown at 2 daytime temperatures (23 °C and 34 °C), and either well-watered or subject to a 1 month drought prior to harvest at 6 months. The objective was to determine the separate and interactive effects of temperature and drought on growth and toxicity. Both temperature and drought affected cassava physiology and chemistry. While temperature alone drove differences in plant height and above-ground biomass, drought and temperature × drought interactions most affected tuber yield, as well as foliar and tuber chemistry, including C : N, nitrogen and cyanide potential (CNp; total cyanide released from cyanogenic glucosides). Conditions that most stimulated growth and yield (well-watered × high temperature) effected a reduction in tuber toxicity, whereas drought inhibited growth and yield, and was associated with increased foliar and tuber toxicity. The magnitude of drought effects on tuber yield and toxicity were greater at high temperature; thus, increases in tuber CNp were not merely a consequence of reduced tuber biomass. Findings confirm that cassava is adaptable to forecast temperature increases, particularly in areas of adequate or increasing rainfall; however, in regions forecast for increased incidence of drought, the effects of drought on both food quality (tuber toxicity) and yield are a greater threat to future food security and indicate an increasing necessity for processing of cassava to reduce toxicity.


Subject(s)
Climate Change , Food Supply , Manihot , Droughts , Temperature
10.
J Nerv Ment Dis ; 203(12): 896-900, 2015 Dec.
Article in English | MEDLINE | ID: mdl-26524515

ABSTRACT

The Patient Protection and Affordable Care Act focuses on improving consumer engagement and patient-centered care. This article describes the design and rationale of a study targeting family engagement in pediatric mental health services. The study is a 90-day randomized trial of a telephone-delivered Family Navigator services versus usual care for parents of Medicaid-insured youth younger than 13 years with serious mental illness. Youth are identified through a pediatric antipsychotic medication preauthorization program. Family Navigators offer peer support to empower and engage parents in their child's recovery. Outcomes include parent report of empowerment, social support, satisfaction with child mental health services, and child functioning as well as claims-based measures of psychotherapy service utilization and antipsychotic medication dosage. The focus on "family-centered" care in this study is strongly supported by the active role of consumers in study design and implementation.

11.
Organogenesis ; 11(2): 47-57, 2015.
Article in English | MEDLINE | ID: mdl-26252820

ABSTRACT

Advances in organ regeneration have been facilitated by gentle decellularization protocols that maintain distinct tissue compartments, and thereby allow seeding of blood vessels with endothelial lineages separate from populations of the parenchyma with tissue-specific cells. We hypothesized that a reconstituted vasculature could serve as a novel platform for perfusing cells derived from a different organ: thus discordance of origin between the vascular and functional cells, leading to a hybrid repurposed organ. The need for a highly vascular bed is highlighted by tissue engineering approaches that involve transplantation of just cells, as attempted for insulin production to treat human diabetes. Those pancreatic islet cells present unique challenges since large numbers are needed to allow the cell-to-cell signaling required for viability and proper function; however, increasing their number is limited by inadequate perfusion and hypoxia. As proof of principle of the repurposed organ methodology we harnessed the vasculature of a kidney scaffold while seeding the collecting system with insulin-producing cells. Pig kidneys were decellularized by sequential detergent, enzymatic and rinsing steps. Maintenance of distinct vascular and collecting system compartments was demonstrated by both fluorescent 10 micron polystyrene microspheres and cell distributions in tissue sections. Sterilized acellular scaffolds underwent seeding separately via the artery (fibroblasts or endothelioma cells) and retrograde (murine ßTC-tet cells) up the ureter. After three-day bioreactor incubation, histology confirmed separation of cells in the vasculature from those in the collecting system. ßTC-tet clusters survived in tubules, glomerular Bowman's space, demonstrated insulin immunolabeling, and thereby supported the feasibility of kidney-to-pancreas repurposing.


Subject(s)
Bioprosthesis , Kidney/growth & development , Kidneys, Artificial , Pancreas, Artificial , Tissue Engineering/instrumentation , Tissue Scaffolds , Animals , Equipment Design , Equipment Failure Analysis , Equipment Reuse , Kidney/cytology , Mice , Swine
12.
Am J Pathol ; 185(6): 1552-63, 2015 Jun.
Article in English | MEDLINE | ID: mdl-25843683

ABSTRACT

Hepatic progenitor/oval cell (OC) activation occurs when hepatocyte proliferation is inhibited and is tightly associated with the fibrogenic response during severe liver damage. Connective tissue growth factor (CTGF) is important for OC activation and contributes to the pathogenesis of liver fibrosis. By using the Yeast Two-Hybrid approach, we identified a disintegrin and metalloproteinase with thrombospondin repeat 7 (ADAMTS7) as a CTGF binding protein. In vitro characterization demonstrated CTGF binding and processing by ADAMTS7. Moreover, Adamts7 mRNA was induced during OC activation, after the implantation of 2-acetylaminofluorene with partial hepatectomy in rats or on feeding a 3,5-diethoxycarbonyl-1,4-dihydrocollidine (DDC) diet in mice. X-Gal staining showed Adamts7 expression in hepatocyte nuclear factor 4α(+) hepatocytes and desmin(+) myofibroblasts surrounding reactive ducts in DDC-treated Adamts7(-/-) mice carrying a knocked-in LacZ gene. Adamts7 deficiency was associated with higher transcriptional levels of Ctgf and OC markers and enhanced OC proliferation compared to Adamts7(+/+) controls during DDC-induced liver injury. We also observed increased α-smooth muscle actin and procollagen type I mRNAs, large fibrotic areas in α-smooth muscle actin and Sirius red staining, and increased production of hepatic collagen by hydroxyproline measurement. These results suggest that ADAMTS7 is a new protease for CTGF protein and a novel regulator in the OC compartment, where its absence causes CTGF accumulation, leading to increased OC activation and biliary fibrosis.


Subject(s)
Connective Tissue Growth Factor/metabolism , Disintegrins/metabolism , Liver Cirrhosis/metabolism , Liver/metabolism , Stem Cell Niche/physiology , Thrombospondins/metabolism , ADAM Proteins/genetics , ADAM Proteins/metabolism , ADAMTS7 Protein , Animals , Connective Tissue Growth Factor/genetics , Disintegrins/genetics , Liver/pathology , Liver Cirrhosis/pathology , Liver Regeneration/physiology , Mice , Mice, Knockout , Thrombospondins/genetics
13.
Hepatology ; 61(2): 678-91, 2015 Feb.
Article in English | MEDLINE | ID: mdl-25203810

ABSTRACT

UNLABELLED: Connective tissue growth factor (CTGF) is a matricellular protein that mediates cell-matrix interaction through various subtypes of integrin receptors. This study investigated the role of CTGF and integrin αvß6 in hepatic progenitor/oval cell activation, which often occurs in the form of ductular reactions (DRs) when hepatocyte proliferation is inhibited during severe liver injury. CTGF and integrin αvß6 proteins were highly expressed in DRs of human cirrhotic livers and cholangiocarcinoma. Confocal microscopy analysis of livers from Ctgf promoter-driven green fluorescent protein reporter mice suggested that oval cells and cholangiocytes were the main sources of CTGF and integrin αvß6 during liver injury induced by 3,5-diethoxycarbonyl-1,4-dihydrocollidine (DDC). Deletion of exon 4 of the Ctgf gene using tamoxifen-inducible Cre-loxP system down-regulated integrin αvß6 in DDC-damaged livers of knockout mice. Ctgf deficiency or inhibition of integrin αvß6, by administrating the neutralizing antibody, 6.3G9 (10 mg/kg body weight), caused low levels of epithelial cell adhesion molecule and cytokeratin 19 gene messenger RNAs. Also, there were smaller oval cell areas, fewer proliferating ductular epithelial cells, and lower cholestasis serum markers within 2 weeks after DDC treatment. Associated fibrosis was attenuated, as indicated by reduced expression of fibrosis-related genes, smaller areas of alpha-smooth muscle actin staining, and low collagen production based on hydroxyproline content and Sirius Red staining. Finally, integrin αvß6 could bind to CTGF mediating oval cell adhesion to CTGF and fibronection substrata and promoting transforming growth factor (TGF)-ß1 activation in vitro. CONCLUSIONS: CTGF and integrin αvß6 regulate oval cell activation and fibrosis, probably through interacting with their common matrix and signal partners, fibronectin and TGF-ß1. CTGF and integrin αvß6 are potential therapeutic targets to control DRs and fibrosis in related liver disease.


Subject(s)
Antigens, Neoplasm/metabolism , Chemical and Drug Induced Liver Injury/metabolism , Connective Tissue Growth Factor/metabolism , Integrins/metabolism , Liver Cirrhosis/metabolism , Adult Stem Cells/metabolism , Animals , Bile Duct Neoplasms/metabolism , Bile Ducts, Intrahepatic , Cell Adhesion , Cholangiocarcinoma/metabolism , Female , Fibronectins/metabolism , Humans , Male , Mice , Mice, Knockout , Pyridines , Rabbits , Rats , Transforming Growth Factor beta1/metabolism
14.
FASEB J ; 27(12): 5022-33, 2013 Dec.
Article in English | MEDLINE | ID: mdl-24043261

ABSTRACT

It has been hypothesized that the peripheral taste system may be modulated in the context of an animal's metabolic state. One purported mechanism for this phenomenon is that circulating gastrointestinal peptides modulate the functioning of the peripheral gustatory system. Recent evidence suggests endocrine signaling in the oral cavity can influence food intake (FI) and satiety. We hypothesized that these hormones may be affecting FI by influencing taste perception. We used immunohistochemistry along with genetic knockout models and the specific reconstitution of peptide YY (PYY) in saliva using gene therapy protocols to identify a role for PYY signaling in taste. We show that PYY is expressed in subsets of taste cells in murine taste buds. We also show, using brief-access testing with PYY knockouts, that PYY signaling modulates responsiveness to bitter-tasting stimuli, as well as to lipid emulsions. We show that salivary PYY augmentation, via viral vector therapy, rescues behavioral responsiveness to a lipid emulsion but not to bitter stimuli and that this response is likely mediated via activation of Y2 receptors localized apically in taste cells. Our findings suggest distinct functions for PYY produced locally in taste cells vs. that circulating systemically.


Subject(s)
Peptide YY/metabolism , Satiety Response , Taste , Animals , Eating , Mice , Mice, Knockout , Peptide YY/genetics , Receptors, Neuropeptide Y/genetics , Receptors, Neuropeptide Y/metabolism , Taste Buds/metabolism
15.
PLoS One ; 7(9): e46358, 2012.
Article in English | MEDLINE | ID: mdl-23050020

ABSTRACT

Peptide hormones and their cognate receptors belonging to neuropeptide Y (NPY) family mediate diverse biological functions in a number of tissues. Recently, we discovered the presence of the gut satiation peptide YY (PYY) in saliva of mice and humans and defined its role in the regulation of food intake and body weight maintenance. Here we report the systematic analysis of expression patterns of all NPY receptors (Rs), Y1R, Y2R, Y4R, and Y5R in lingual epithelia in mice. Using four independent assays, immunohistochemistry, in situ hybridization, immunocytochemistry and RT PCR, we show that the morphologically different layers of the keratinized stratified epithelium of the dorsal layer of the tongue express Y receptors in a very distinctive yet overlapping pattern. In particular, the monolayer of basal progenitor cells expresses both Y1 and Y2 receptors. Y1Rs are present in the parabasal prickle cell layer and the granular layer, while differentiated keratinocytes display abundant Y5Rs. Y4Rs are expressed substantially in the neuronal fibers innervating the lamina propria and mechanoreceptors. Basal epithelial cells positive for Y2Rs respond robustly to PYY(3-36) by increasing intracellular Ca(2+) suggesting their possible functional interaction with salivary PYY. In taste buds of the circumvallate papillae, some taste receptor cells (TRCs) express YRs localized primarily at the apical domain, indicative of their potential role in taste perception. Some of the YR-positive TRCs are co-localized with neuronal cell adhesion molecule (NCAM), suggesting that these TRCs may have synaptic contacts with nerve terminals. In summary, we show that all YRs are abundantly expressed in multiple lingual cell types, including epithelial progenitors, keratinocytes, neuronal dendrites and TRCs. These results suggest that these receptors may be involved in the mediation of a wide variety of functions, including proliferation, differentiation, motility, taste perception and satiation.


Subject(s)
Epithelium/metabolism , Receptors, Neuropeptide Y/metabolism , Tongue/cytology , Animals , Cell Line , Humans , In Situ Hybridization , In Vitro Techniques , Mice , Receptors, Neuropeptide Y/genetics , Reverse Transcriptase Polymerase Chain Reaction
16.
Ecol Evol ; 2(7): 1712-24, 2012 Jul.
Article in English | MEDLINE | ID: mdl-22957175

ABSTRACT

Increases in the frequency, duration, and severity of regional drought pose major threats to the health and integrity of downstream ecosystems. During 2007-2008, the U.S. southeast experienced one of the most severe droughts on record. Drought and water withdrawals in the upstream watershed led to decreased freshwater input to Apalachicola Bay, Florida, an estuary that is home to a diversity of commercially and ecologically important organisms. This study applied a combination of laboratory experiments and field observations to investigate the effects of reduced freshwater input on Apalachicola oysters. Oysters suffered significant disease-related mortality under high-salinity, drought conditions, particularly during the warm summer months. Mortality was size-specific, with large oysters of commercially harvestable size being more susceptible than small oysters. A potential salinity threshold was revealed between 17 and 25 ppt, where small oysters began to suffer mortality, and large oysters exhibited an increase in mortality. These findings have important implications for watershed management, because upstream freshwater releases could be carefully timed and allocated during stressful periods of the summer to reduce disease-related oyster mortality. Integrated, forward-looking water management is needed, particularly under future scenarios of climate change and human population growth, to sustain the valuable ecosystem services on which humans depend.

17.
Am J Physiol Lung Cell Mol Physiol ; 301(6): L860-71, 2011 Dec.
Article in English | MEDLINE | ID: mdl-21873446

ABSTRACT

Intrauterine growth restriction (IUGR) increases the risk for bronchopulmonary dysplasia (BPD). Abnormal lung structure has been noted in animal models of IUGR, but whether IUGR adversely impacts fetal pulmonary vascular development and pulmonary artery endothelial cell (PAEC) function is unknown. We hypothesized that IUGR would decrease fetal pulmonary alveolarization, vascular growth, and in vitro PAEC function. Studies were performed in an established model of severe placental insufficiency and IUGR induced by exposing pregnant sheep to elevated temperatures. Alveolarization, quantified by radial alveolar counts, was decreased 20% (P < 0.005) in IUGR fetuses. Pulmonary vessel density was decreased 44% (P < 0.01) in IUGR fetuses. In vitro, insulin increased control PAEC migration, tube formation, and nitric oxide (NO) production. This response was absent in IUGR PAECs. VEGFA stimulated tube formation, and NO production also was absent. In control PAECs, insulin increased cell growth by 68% (P < 0.0001). Cell growth was reduced in IUGR PAECs by 29% at baseline (P < 0.01), and the response to insulin was attenuated (P < 0.005). Despite increased basal and insulin-stimulated Akt phosphorylation in IUGR PAECs, endothelial NO synthase (eNOS) protein expression as well as basal and insulin-stimulated eNOS phosphorylation were decreased in IUGR PAECs. Both VEGFA and VEGFR2 also were decreased in IUGR PAECs. We conclude that fetuses with IUGR are characterized by decreased alveolar and vascular growth and PAEC dysfunction in vitro. This may contribute to the increased risk for adverse respiratory outcomes and BPD in infants with IUGR.


Subject(s)
Endothelial Cells/pathology , Fetal Growth Retardation/pathology , Pulmonary Alveoli/embryology , Pulmonary Artery/embryology , Sheep/embryology , Animals , Blood Vessels/embryology , Blood Vessels/pathology , Cell Aggregation , Cell Hypoxia , Cell Movement , Cell Proliferation , Cells, Cultured , Endothelial Cells/enzymology , Female , Fetal Growth Retardation/physiopathology , Gene Expression , Insulin/pharmacology , Lung/embryology , Lung/pathology , Nitric Oxide/metabolism , Nitric Oxide Synthase Type III/genetics , Nitric Oxide Synthase Type III/metabolism , Phosphorylation , Pregnancy , Primary Cell Culture , Proto-Oncogene Proteins c-akt/metabolism , Pulmonary Alveoli/blood supply , Pulmonary Artery/pathology , Pulmonary Artery/physiopathology , Receptor, Insulin/metabolism , Signal Transduction , Vascular Endothelial Growth Factor A/metabolism , Vascular Endothelial Growth Factor Receptor-2/metabolism
18.
J Appl Physiol (1985) ; 111(1): 192-9, 2011 Jul.
Article in English | MEDLINE | ID: mdl-21551011

ABSTRACT

The purpose of this study was to determine if PKB signaling is decreased and contractile protein degradation is increased in extensor digitorum longus (EDL) and soleus (SOL) muscles from middle-aged (MA) and aged (AG) mice. We also examined the effect of age on atrogene expression in quadriceps muscle. PKB activity, as assessed by Thr(308) and Ser(473) phosphorylation, was significantly higher in EDL and SOL muscles from AG than MA mice. The age-related increase in PKB activity appears to be due to an increase in expression of the kinase, as PKB-α and PKB-ß levels were significantly higher in EDL and SOL muscles from AG than MA mice. The phosphorylation of forkhead box 3a (FOXO3a) on Thr(32), a PKB target, was significantly higher in EDL muscles from AG than MA mice. The rate of contractile protein degradation was similar in EDL and SOL muscles from AG and MA mice. Atrogin-1 and muscle-specific RING finger protein 1 (MuRF-1) mRNA levels did not change in muscles from AG compared with MA mice, indicating that ubiquitin-proteasome proteolysis does not contribute to sarcopenia. A significant decrease in Bcl-2 and 19-kDa interacting protein 3 (Bnip3) and GABA receptor-associated protein 1 (Gabarap1) mRNA was observed in muscles from AG compared with MA mice, which may contribute to age-related contractile dysfunction. In conclusion, the mechanisms responsible for sarcopenia are distinct from experimental models of atrophy and do not involve atrogin-1 and MuRF-1 or enhanced proteolysis. Finally, a decline in autophagy-related gene expression may provide a novel mechanism for impaired contractile function and muscle metabolism with advancing age.


Subject(s)
Aging/metabolism , Muscular Atrophy/enzymology , Proto-Oncogene Proteins c-akt/metabolism , Quadriceps Muscle/enzymology , Sarcopenia/enzymology , Signal Transduction , Age Factors , Aging/genetics , Animals , Apoptosis Regulatory Proteins , Autophagy/genetics , Cytoskeletal Proteins/genetics , Forkhead Box Protein O3 , Forkhead Transcription Factors/genetics , Forkhead Transcription Factors/metabolism , Gene Expression Regulation , Insulin/metabolism , Male , Membrane Proteins/genetics , Mice , Mice, Inbred C57BL , Microtubule-Associated Proteins , Mitochondrial Proteins/genetics , Muscle Proteins/genetics , Muscular Atrophy/genetics , Muscular Atrophy/pathology , Phosphorylation , Proto-Oncogene Proteins c-bcl-2/genetics , Quadriceps Muscle/pathology , RNA, Messenger/metabolism , SKP Cullin F-Box Protein Ligases/genetics , Sarcopenia/genetics , Sarcopenia/pathology , Serine , Threonine , Tripartite Motif Proteins , Ubiquitin-Protein Ligases/genetics
19.
Organogenesis ; 6(2): 134-6, 2010.
Article in English | MEDLINE | ID: mdl-20885860

ABSTRACT

We have developed a method for the decellularization of whole rat livers by perfusion with increasing concentrations of detergents. This procedure resulted in an intact, decellularized organ with an intact liver capsule. These decellularized organs were analyzed by immunohistochemistry, and retained an appropriate distribution of extracellular matrix components. The laminin basement membranes of the liver vasculature also remain intact. These acellular vessel remnants were strong enough to be cannulated, providing a convenient means for the delivery of cells to areas deep within the decellularized organ. Cannulation of the extrahepatic vessel remnants allow for media to be circulated through the decellularized organ. These decellularized livers provide a natural matrix for research in the fields of bio-artificial livers and liver engineering.


Subject(s)
Liver/cytology , Tissue Culture Techniques/methods , Animals , Liver/blood supply , Perfusion , Rats , Rats, Inbred F344
20.
Stem Cells Dev ; 18(1): 37-46, 2009.
Article in English | MEDLINE | ID: mdl-18393672

ABSTRACT

Adult bone marrow (BM)-derived insulin-producing cells (IPCs) are capable of regulating blood glucose levels in chemically induced hyperglycemic mice. Using cell transplantation therapy, fully functional BM-derived IPCs help to mediate treatment of diabetes mellitus. Here, we demonstrate the detection of the pentose phosphate pathway enzyme, transketolase (TK), in BM-derived IPCs cultured under high-glucose conditions. Benfotiamine, a known activator of TK, was not shown to affect the proliferation of insulinoma cell line, INS-1; however, when INS-1 cells were cultured with oxythiamine, an inhibitor of TK, cell proliferation was suppressed. Treatment with benfotiamine activated glucose metabolism in INS-1 cells in high-glucose culture conditions, and appeared to maximize the BM-derived IPCs ability to synthesize insulin. Benfotiamine was not shown to induce the glucose receptor Glut-2, however it was shown to activate glucokinase, the enzyme responsible for conversion of glucose to glucose-6-phosphate. Furthermore, benfotiamine-treated groups showed upregulation of the downstream glycolytic enzyme, glyceraldehyde phosphate dehydrogenase (GAPDH). However, in cells where the pentose phosphate pathway was blocked by oxythiamine treatment, there was a clear downregulation of Glut-2, glucokinase, insulin, and GAPDH. When benfotiamine was used to treat mice transplanted with BM-derived IPCs transplanted, their glucose level was brought to a normal range. The glucose challenge of normal mice treated with benfotiamine lead to rapidly normalized blood glucose levels. These results indicate that benfotiamine activates glucose metabolism and insulin synthesis to prevent glucose toxicity caused by high concentrations of blood glucose in diabetes mellitus.


Subject(s)
Adjuvants, Immunologic/pharmacology , Bone Marrow Cells , Glucose/metabolism , Insulin/metabolism , Thiamine/analogs & derivatives , Transketolase/metabolism , Animals , Antimetabolites/pharmacology , Bone Marrow Cells/cytology , Bone Marrow Cells/drug effects , Bone Marrow Cells/metabolism , Cell Differentiation/physiology , Cell Line , Cell Proliferation , Cell Transplantation , Diabetes Mellitus, Experimental/metabolism , Glyceraldehyde-3-Phosphate Dehydrogenase (Phosphorylating)/metabolism , Humans , Hyperglycemia/metabolism , Hyperglycemia/physiopathology , Male , Mice , Oxythiamine/pharmacology , Rats , Thiamine/pharmacology , Transketolase/genetics
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