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1.
Materials (Basel) ; 17(9)2024 Apr 25.
Article in English | MEDLINE | ID: mdl-38730814

ABSTRACT

Super duplex stainless steel (SDSS) is a suitable structural material for various engineering applications due to its outstanding strength and corrosion resistance. In particular, its high-temperature strength can enhance the safety of electronic products and cars. SDSS AISI2507, known for its excellent strength and high corrosion resistance, was analyzed for its microstructure and electrochemical behavior at the ignition temperature of Li-ion batteries, 700 °C. At 700 °C, AISI2507 exhibited secondary phase precipitation values of 1% and 8% after 5 and 10 h, respectively. Secondary phase precipitation was initiated by the expansion of austenite, forming sigma, chi, and CrN phases. The electrochemical behavior varied with the fraction of secondary phases. Secondary phase precipitation reduced the potential (From -0.25 V to -0.31 V) and increased the current density (From 8 × 10-6 A/cm2 to 3 × 10-6 A/cm2) owing to galvanic corrosion by sigma and chi. As the fraction of secondary phases increased (From 0.0% to 8.1%), the open circuit potential decreased (From -0.25 V to -0.32 V). Secondary phase precipitation is a crucial factor in reducing the corrosion resistance of SDSS AISI2507 and occurs after 1 h of exposure at 700 °C.

2.
Nature ; 628(8008): 596-603, 2024 Apr.
Article in English | MEDLINE | ID: mdl-38509371

ABSTRACT

Motor neurons are the final common pathway1 through which the brain controls movement of the body, forming the basic elements from which all movement is composed. Yet how a single motor neuron contributes to control during natural movement remains unclear. Here we anatomically and functionally characterize the individual roles of the motor neurons that control head movement in the fly, Drosophila melanogaster. Counterintuitively, we find that activity in a single motor neuron rotates the head in different directions, depending on the starting posture of the head, such that the head converges towards a pose determined by the identity of the stimulated motor neuron. A feedback model predicts that this convergent behaviour results from motor neuron drive interacting with proprioceptive feedback. We identify and genetically2 suppress a single class of proprioceptive neuron3 that changes the motor neuron-induced convergence as predicted by the feedback model. These data suggest a framework for how the brain controls movements: instead of directly generating movement in a given direction by activating a fixed set of motor neurons, the brain controls movements by adding bias to a continuing proprioceptive-motor loop.


Subject(s)
Drosophila melanogaster , Motor Neurons , Movement , Posture , Proprioception , Animals , Drosophila melanogaster/anatomy & histology , Drosophila melanogaster/genetics , Drosophila melanogaster/physiology , Feedback, Physiological/physiology , Head/physiology , Models, Neurological , Motor Neurons/physiology , Movement/physiology , Posture/physiology , Proprioception/genetics , Proprioception/physiology , Male
3.
Materials (Basel) ; 17(6)2024 Mar 21.
Article in English | MEDLINE | ID: mdl-38541595

ABSTRACT

The development of Li-ion battery cases requires superior electrical conductivity, strength, and corrosion resistance for both cathode and anode to enhance safety and performance. Among the various battery case materials, super duplex stainless steel (SDSS), which is composed of austenite and ferrite as two-phase stainless steel, exhibits outstanding strength and corrosion resistance. However, stainless steel, which is an iron-based material, tends to have lower electrical conductivity. Nevertheless, nickel-plating SDSS can achieve excellent electrical conductivity, making it suitable for Li-ion battery cases. Therefore, this study analysed the plating behaviour of SDSS plates after nickel plating to leverage their exceptional strength and corrosion resistance. Electroless Ni plating was performed to analyse the plating behaviour, and the plating behaviour was studied with reference to different plating durations. Heat treatment was conducted at 1000 °C for one hour, followed by cooling at 50 °C/s. Post-heat treatment, the analysis of phases was executed using FE-SEM, EDS, and EPMA. Electroless Ni plating was performed at 60-300 s. The plating duration after the heat treatment was up to 300 s, and the behaviour of the materials was observed using FE-SEM. The phase analysis concerning different plating durations was conducted using XRD. Post-heat treatment, the precipitated secondary phases in SAF2507 were identified as Sigma, Chi, and CrN, approximating a 13% distribution. During the electroless Ni plating, the secondary phase exhibited a plating rate equivalent to that of ferrite, entirely plating at around 180 s. Further increments in plating time displayed growth of the plating layer from the austenite direction towards the ferrite, accompanied by a reduced influence from the substrate. Despite the differences in composition, both the secondary phase and austenite demonstrated comparable plating rates, showing that electroless Ni plating on SDSS was primarily influenced by the substrate, a finding which was primarily confirmed through phase analysis.

4.
Sci Rep ; 14(1): 4140, 2024 02 20.
Article in English | MEDLINE | ID: mdl-38374383

ABSTRACT

The present study aimed to compare clinical and radiological differences of ONFH patients who were treated with denosumab, and a control group. A total of 178 patients (272 hips) with symptomatic, nontraumatic ONFH were divided into a denosumab group (98 patients, 146 hips) and a control group (80 patients, 126 hips). Patients in the denosumab group received a 60 mg subcutaneous dose of denosumab every 6 months. For the clinical assessments, Harris hip scores (HHS), Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) were evaluated. Plain radiographs and MRI were performed before and a minimum of 1 year after administration of denosumab, which were evaluated for radiological results including femoral head collapse (≥ 2 mm) and volume change of necrotic lesion. Femoral head collapse occurred in 36 hips (24.7%) in the denosumab group, and 48 hips (38.1%) in the control group, which was statistically significant (P = 0.012). Twenty-three hips (15.8%) in the denosumab group and 29 hips (23%) in the control group required THA, which showed no significant difference (P = 0.086). At the final follow-up, 71.9% of hips in the denosumab group had a good or excellent HHS compared with 48.9% in the control group, showing a significant difference (P = 0.012). The denosumab group showed a significantly higher rate of necrotic lesion volume reductions compared with the control group (P < 0.001). Denosumab can significantly reduce the volume of necrotic lesions and prevent femoral head collapse in patients with ARCO stage I or II ONFH.


Subject(s)
Denosumab , Femur Head Necrosis , Humans , Denosumab/therapeutic use , Retrospective Studies , Femur Head/diagnostic imaging , Femur Head/pathology , Femur Head Necrosis/diagnostic imaging , Femur Head Necrosis/drug therapy , Femur Head Necrosis/pathology , Hip/pathology , Treatment Outcome
5.
Biosens Bioelectron ; 240: 115603, 2023 Nov 15.
Article in English | MEDLINE | ID: mdl-37647686

ABSTRACT

The skin microbiome is thought to play a critical role in maintaining skin health and protecting against infection. While most microorganisms that live on the skin are harmless or even beneficial, some can cause skin infections or other health problems, emphasizing the importance of diagnosis of the composition and diversity of the skin flora. However, conventional diagnostic methods for evaluation of the skin microbiome are not sensitive enough to detect bacteria at low concentrations and suffer from poor specificity, thus limiting early diagnosis of bacterial infections. In this study, we developed novel approaches for bacterial species detection and identification methods with single-cell sensitivity using super-resolution microscopy and AI-based image analysis: a protein quantification-based method and an AI-based bacterial image analysis method. We demonstrate that these methods can differentiate between common bacterial members of the skin flora, including Staphylococcus aureus and Staphylococcus epidermidis, and different ribotypes of Cutibacterium acnes, both in purified bacterial samples and in scaling skin samples. The advantages of these methods, including the lack of time-consuming amplification or purification steps and single-cell level detection sensitivity, allow early diagnosis of bacterial infections, even from bacterial samples at extremely low concentrations, thus showing promise as a next-generation platform for microbiome detection as single-cell diagnostics.


Subject(s)
Biosensing Techniques , Skin , Optical Imaging , Staphylococcus epidermidis , Artificial Intelligence
7.
Int Orthop ; 47(5): 1315-1321, 2023 05.
Article in English | MEDLINE | ID: mdl-36829086

ABSTRACT

PURPOSE: This study aimed to evaluate the clinical and radiologic characteristics of the fatigue-type of SSFFH in healthy military recruits. MATERIALS AND METHOD: We retrospectively analyzed 39 hips from 32 patients who were treated for SSFFH between 2014 and 2018. Clinical variables were analyzed. We devised a categorization system that divided SSFFH into five types (A-E) according to the extent of the fracture line MRI axial view. The femoral head was divided into three parts for the categorization: the anterior third, middle third, and posterior third. RESULTS: The included patients were 39 hips from 32 patients with the mean age 22.3 years. Almost all patients with SSFFH (96.9%) complained of hip pain with limping at the time of diagnosis. The mean time to the onset of the hip pain from the beginning of military training was 24.8 days. There were seven patients (21.9%) with concomitant stress fractures on whole-body bone scan. Six hips (15.4%) developed osteoarthritis and required surgery. Almost all the cases (94.9%) involved the anterior compartment of the femoral head. CONCLUSIONS: Military recruits with the hip pain and limping within one month of military training should undergo detailed evaluation. A whole-body bone scan with SPECT is useful for identifying other concomitant stress fractures. Majority of SSFFH involved the anterior compartment of the femoral head.


Subject(s)
Fractures, Stress , Military Personnel , Humans , Young Adult , Adult , Fractures, Stress/diagnostic imaging , Fractures, Stress/therapy , Femur Head/diagnostic imaging , Retrospective Studies , Magnetic Resonance Imaging , Arthralgia , Pain
8.
Nature ; 613(7944): 534-542, 2023 01.
Article in English | MEDLINE | ID: mdl-36599984

ABSTRACT

To survive, animals must convert sensory information into appropriate behaviours1,2. Vision is a common sense for locating ethologically relevant stimuli and guiding motor responses3-5. How circuitry converts object location in retinal coordinates to movement direction in body coordinates remains largely unknown. Here we show through behaviour, physiology, anatomy and connectomics in Drosophila that visuomotor transformation occurs by conversion of topographic maps formed by the dendrites of feature-detecting visual projection neurons (VPNs)6,7 into synaptic weight gradients of VPN outputs onto central brain neurons. We demonstrate how this gradient motif transforms the anteroposterior location of a visual looming stimulus into the fly's directional escape. Specifically, we discover that two neurons postsynaptic to a looming-responsive VPN type promote opposite takeoff directions. Opposite synaptic weight gradients onto these neurons from looming VPNs in different visual field regions convert localized looming threats into correctly oriented escapes. For a second looming-responsive VPN type, we demonstrate graded responses along the dorsoventral axis. We show that this synaptic gradient motif generalizes across all 20 primary VPN cell types and most often arises without VPN axon topography. Synaptic gradients may thus be a general mechanism for conveying spatial features of sensory information into directed motor outputs.


Subject(s)
Behavior, Animal , Drosophila , Neurons , Psychomotor Performance , Synapses , Animals , Brain/cytology , Brain/physiology , Drosophila/anatomy & histology , Drosophila/cytology , Drosophila/physiology , Neurons/physiology , Visual Fields/physiology , Synapses/metabolism , Axons , Dendrites , Escape Reaction
9.
Molecules ; 25(20)2020 Oct 14.
Article in English | MEDLINE | ID: mdl-33066640

ABSTRACT

In order to achieve premium quality with crop production, techniques involving the adjustment of nutrient supply and/or supplemental lighting with specific light quality have been applied. To examine the effects of low mineral supply and supplemental lighting, we performed non-targeted metabolite profiling of leaves and stems of the medicinal herb Perilla frutescens, grown under a lower (0.75×) and lowest (0.1×) supply of different minerals (N, K, or Mg) and under supplemental light-emitting diode (LED) lighting (red, blue, or red-blue combination). The lowest N supply increased flavonoids, and the lowest K or Mg slightly increased rosmarinic acid and some flavonoids in the leaves and stems. Supplemental LED lighting conditions (red, blue, or red-blue combination) significantly increased the contents of chlorophyll, most cinnamic acid derivatives, and rosmarinic acid in the leaves. LED lighting with either blue or the red-blue combination increased antioxidant activity compared with the control group without LED supplementation. The present study demonstrates that the cultivation of P. frutescens under low mineral supply and supplemental LED lighting conditions affected metabolic compositions, and we carefully suggest that an adjustment of minerals and light sources could be applied to enhance the levels of targeted metabolites in perilla.


Subject(s)
Perilla frutescens/metabolism , Plants, Medicinal/metabolism , Chlorophyll/metabolism , Chromatography, High Pressure Liquid/methods , Cinnamates/metabolism , Depsides/metabolism , Flavonoids/metabolism , Lighting , Magnesium/metabolism , Metabolomics/methods , Minerals/metabolism , Nitrogen/metabolism , Perilla frutescens/chemistry , Plant Leaves/chemistry , Plant Leaves/metabolism , Plant Stems/chemistry , Plant Stems/metabolism , Plants, Medicinal/chemistry , Potassium/metabolism , Tandem Mass Spectrometry , Rosmarinic Acid
10.
PLoS One ; 13(6): e0198739, 2018.
Article in English | MEDLINE | ID: mdl-29879203

ABSTRACT

Plants are an important and inexhaustible source of bioactive molecules in food, medicine, agriculture, and industry. In this study, we performed systematic liquid chromatography-mass spectrometry (LC-MS)-based metabolic profiling coupled with antioxidant assays for indigenous plant family extracts. Partial least-squares discriminant analysis of LC-MS datasets for the extracts of 34 plant species belonging to the families Aceraceae, Asteraceae, and Rosaceae showed that these species were clustered according to their respective phylogenies. In particular, seven Aceraceae species were clearly demarcated with higher average antioxidant activities, rationalizing their application for bioconversion studies. On the basis of further evaluation of the interspecies variability of metabolic profiles and antioxidant activities among Aceraceae family plants, we found that Acer tataricum (TA) extracts were clearly distinguished from those of other species, with a higher relative abundance of tannin derivatives. Further, we detected a strong positive correlation between most tannin derivatives and the observed higher antioxidant activities. Following Aspergillus oryzae-mediated fermentative bioconversion of Acer plant extracts, we observed a time-correlated (0-8 days) linear increase in antioxidant phenotypes for all species, with TA having the highest activity. Temporal analysis of the MS data revealed tannin bioconversion mechanisms with a relatively higher abundance of gallic acid (m/z 169) accumulated at the end of 8 days, particularly in TA. Similarly, quercetin precursor (glycoside) metabolites were also transformed to quercetin aglycones (m/z 301) in most Acer plant extracts. The present study underscores the efficacy of fermentative bioconversion strategies aimed at enhancing the quality and availability of bioactive metabolites from plant extracts.


Subject(s)
Acer/chemistry , Acer/metabolism , Aspergillus oryzae/growth & development , Metabolome , Plant Extracts/chemistry , Antioxidants/chemistry , Antioxidants/metabolism , Chromatography, Liquid , Gallic Acid/chemistry , Gallic Acid/metabolism , Mass Spectrometry , Metabolomics , Quercetin/chemistry , Quercetin/metabolism , Tannins/chemistry , Tannins/metabolism
11.
Circ J ; 81(10): 1528-1536, 2017 Sep 25.
Article in English | MEDLINE | ID: mdl-28883215

ABSTRACT

BACKGROUND: The aim of this study is to identify the principal circulating factors that modulate atheromatous matrix metalloproteinase (MMP) activity in response to diet and exercise.Methods and Results:Apolipoprotein-E knock-out (ApoE-/-) mice (n=56) with pre-existing plaque, fed either a Western diet (WD) or normal diet (ND), underwent either 10 weeks of treadmill exercise or had no treatment. Atheromatous MMP activity was visualized using molecular imaging with a MMP-2/9 activatable near-infrared fluorescent (NIRF) probe. Exercise did not significantly reduce body weight, visceral fat, and plaque size in either WD-fed animals or ND-fed animals. However, atheromatous MMP-activity was different; ND animals that did or did not exercise had similarly low MMP activities, WD animals that did not exercise had high MMP activity, and WD animals that did exercise had reduced levels of MMP activity, close to the levels of ND animals. Factor analysis and path analysis showed that soluble vascular cell adhesion molecule (sVCAM)-1 was directly positively correlated to atheromatous MMP activity. Adiponectin was indirectly negatively related to atheromatous MMP activity by way of sVCAM-1. Resistin was indirectly positively related to atheromatous MMP activity by way of sVCAM-1. Visceral fat amount was indirectly positively associated with atheromatous MMP activity, by way of adiponectin reduction and resistin elevation. MMP-2/9 imaging of additional mice (n=18) supported the diet/exercise-related anti-atherosclerotic roles for sVCAM-1. CONCLUSIONS: Diet and exercise affect atheromatous MMP activity by modulating the systemic inflammatory milieu, with sVCAM-1, resistin, and adiponectin closely interacting with each other and with visceral fat.


Subject(s)
Cytokines/pharmacology , Diet , Matrix Metalloproteinase 2/metabolism , Matrix Metalloproteinase 9/metabolism , Physical Conditioning, Animal , Plaque, Atherosclerotic/metabolism , Adiponectin/metabolism , Animals , Apolipoproteins E/genetics , Intra-Abdominal Fat/metabolism , Mice , Mice, Knockout , Resistin/metabolism , Vascular Cell Adhesion Molecule-1/metabolism
12.
Mol Pharmacol ; 92(3): 347-357, 2017 09.
Article in English | MEDLINE | ID: mdl-28696213

ABSTRACT

Calcium-dependent inactivation of high voltage-activated Ca2+ channels plays a crucial role in limiting rises in intracellular calcium (Ca2+i). A key mediator of these effects is calmodulin, which has been found to bind the C-terminus of the pore-forming α subunit. In contrast, little is known about how Ca2+i can regulate low voltage-activated T-type Ca2+ channels. Using whole cell patch clamp, we examined the biophysical properties of Ca2+ current through the three T-type Ca2+ channel isoforms, Cav3.1, Cav3.2, or Cav3.3, comparing internal solutions containing 27 nM and l µM free Ca2+ Both activation and inactivation kinetics of Cav3.3 current in l µM Ca2+i solution were more rapid than those in 27 nM Ca2+i solution. In addition, both activation and steady-state inactivation curves of Cav3.3 were negatively shifted in the higher Ca2+i solution. In contrast, the biophysical properties of Cav3.1 and Cav3.2 isoforms were not significantly different between the two internal solutions. Overexpression of CaM1234 (a calmodulin mutant that doesn't bind Ca2+) occluded the effects of l µM Ca2+i on Cav3.3, implying that CaM is involved in the Ca2+i regulation effects on Cav3.3. Yeast two-hybrid screening and co-immunoprecipitation experiments revealed a direct interaction of CaM with the carboxyl terminus of Cav3.3. Taken together, our results suggest that Cav3.3 T-type channel is potently regulated by Ca2+i via interaction of Ca2+/CaM with the carboxyl terminus of Cav3.3.


Subject(s)
Calcium Channels, T-Type/physiology , Calcium/physiology , Calmodulin/physiology , Animals , Calcium Channels, T-Type/chemistry , HEK293 Cells , Humans , Immunoprecipitation , Rats
13.
Sci Rep ; 6: 35137, 2016 10 12.
Article in English | MEDLINE | ID: mdl-27731357

ABSTRACT

Photoacoustic imaging has attracted interest for its capacity to capture functional spectral information with high spatial and temporal resolution in biological tissues. Several photoacoustic imaging systems have been commercialized recently, but they are variously limited by non-clinically relevant designs, immobility, single anatomical utility (e.g., breast only), or non-programmable interfaces. Here, we present a real-time clinical photoacoustic and ultrasound imaging system which consists of an FDA-approved clinical ultrasound system integrated with a portable laser. The system is completely programmable, has an intuitive user interface, and can be adapted for different applications by switching handheld imaging probes with various transducer types. The customizable photoacoustic and ultrasound imaging system is intended to meet the diverse needs of medical researchers performing both clinical and preclinical photoacoustic studies.


Subject(s)
Photoacoustic Techniques/instrumentation , Ultrasonography/instrumentation , Animals , Blood Vessels/diagnostic imaging , Chickens , Computer Systems , Contrast Media , Equipment Design , Female , Gastrointestinal Tract/diagnostic imaging , Humans , Lasers, Solid-State , Nanostructures , Phantoms, Imaging , Rats , Rats, Sprague-Dawley , Software , Transducers , User-Computer Interface
15.
Curr Biol ; 26(15): 1965-1974, 2016 08 08.
Article in English | MEDLINE | ID: mdl-27397890

ABSTRACT

Hunger is a powerful drive that stimulates food intake. Yet, the mechanism that determines how the energy deficits that result in hunger are represented in the brain and promote feeding is not well understood. We previously described SLC5A11-a sodium/solute co-transporter-like-(or cupcake) in Drosophila melanogaster, which is required for the fly to select a nutritive sugar over a sweeter nonnutritive sugar after periods of food deprivation. SLC5A11 acts on approximately 12 pairs of ellipsoid body (EB) R4 neurons to trigger the selection of nutritive sugars, but the underlying mechanism is not understood. Here, we report that the excitability of SLC5A11-expressing EB R4 neurons increases dramatically during starvation and that this increase is abolished in the SLC5A11 mutation. Artificial activation of SLC5A11-expresssing neurons is sufficient to promote feeding and hunger-driven behaviors; silencing these neurons has the opposite effect. Notably, SLC5A11 transcript levels in the brain increase significantly when flies are starved and decrease shortly after starved flies are refed. Furthermore, expression of SLC5A11 is sufficient for promoting hunger-driven behaviors and enhancing the excitability of SLC5A11-expressing neurons. SLC5A11 inhibits the function of the Drosophila KCNQ potassium channel in a heterologous expression system. Accordingly, a knockdown of dKCNQ expression in SLC5A11-expressing neurons produces hunger-driven behaviors even in fed flies, mimicking the overexpression of SLC5A11. We propose that starvation increases SLC5A11 expression, which enhances the excitability of SLC5A11-expressing neurons by suppressing dKCNQ channels, thereby conferring the hunger state.


Subject(s)
Drosophila Proteins/genetics , Drosophila melanogaster/physiology , Food Deprivation , Hunger , Potassium Channels/genetics , Sodium-Glucose Transport Proteins/genetics , Animals , Drosophila Proteins/metabolism , Drosophila melanogaster/genetics , Male , Neurons/metabolism , Potassium Channels/metabolism , Sodium-Glucose Transport Proteins/metabolism
16.
Int J STD AIDS ; 27(11): 1013-5, 2016 10.
Article in English | MEDLINE | ID: mdl-26826158

ABSTRACT

Little is known about differences between immune reconstitution inflammatory syndrome (IRIS) and non-IRIS lymphoma in HIV patients on antiretroviral therapy (ART). The aim of this study was to describe the characteristics of IRIS and non-IRIS lymphoma in Korean HIV-positive patients on ART compared with lymphoma in those off ART. Of 1490 patients, 41 (3%) had lymphoma. Of these, 27 cases (66%) were classified as lymphoma off ART, eight as IRIS lymphoma, and six as non-IRIS lymphoma on ART. Hodgkin lymphoma was significantly more common among patients with non-IRIS lymphoma on ART than among those with lymphoma off ART (P = 0.005), whereas there was no Hodgkin lymphoma among IRIS lymphoma. Stage IV lymphoma was significantly rarer in non-IRIS lymphoma on ART than in lymphoma off ART (P = 0.007). Non-IRIS lymphoma on ART tends to have a better survival rate than lymphoma off ART (Kaplan-Meier survival analysis, P = 0.167), while IRIS lymphoma exhibited a survival rate similar to lymphoma off ART (P = 0.618). In Korean HIV-positive patients, there were significantly more cases of Hodgkin lymphoma of a less advanced stage in non-IRIS lymphoma on ART than in lymphoma off ART, in contrast to IRIS lymphoma.


Subject(s)
AIDS-Related Opportunistic Infections/mortality , Anti-HIV Agents/therapeutic use , Antiretroviral Therapy, Highly Active , HIV Infections/complications , HIV Infections/drug therapy , Immune Reconstitution Inflammatory Syndrome/complications , Lymphoma, AIDS-Related/mortality , Lymphoma, Non-Hodgkin/mortality , AIDS-Related Opportunistic Infections/ethnology , Adult , Female , HIV Infections/ethnology , Humans , Immune Reconstitution Inflammatory Syndrome/ethnology , Immune Reconstitution Inflammatory Syndrome/mortality , Incidence , Kaplan-Meier Estimate , Lymphoma, AIDS-Related/ethnology , Lymphoma, Non-Hodgkin/ethnology , Male , Republic of Korea/epidemiology , Severity of Illness Index , Survival Analysis , Viral Load
17.
Mol Brain ; 8: 87, 2015 Dec 21.
Article in English | MEDLINE | ID: mdl-26692189

ABSTRACT

BACKGROUND: Food intake of the adult fruit fly Drosophila melanogaster, an intermittent feeder, is attributed to several behavioral elements including foraging, feeding initiation and termination, and food ingestion. Despite the development of various feeding assays in fruit flies, how each of these behavioral elements, particularly food ingestion, is regulated remains largely uncharacterized. RESULTS: To this end, we have developed a manual feeding (MAFE) assay that specifically measures food ingestion of an individual fly completely independent of the other behavioral elements. This assay reliably recapitulates the effects of known feeding modulators, and offers temporal resolution in the scale of seconds. Using this assay, we find that fruit flies can rapidly assess the nutritional value of sugars within 20-30 s, and increase the ingestion of nutritive sugars after prolonged periods of starvation. Two candidate nutrient sensors, SLC5A11 and Gr43a, are required for discriminating the nutritive sugars, D-glucose and D-fructose, from their non-nutritive enantiomers, respectively. This suggests that differential sensing mechanisms play a key role in determining food nutritional value. CONCLUSIONS: Taken together, our MAFE assay offers a platform to specifically examine the regulation of food ingestion with excellent temporal resolution, and identifies a fast-acting neural mechanism that assesses food nutritional value and modulates food intake.


Subject(s)
Appetite Regulation/physiology , Drosophila melanogaster/physiology , Feeding Behavior/physiology , Fructose , Glucose , Nutritive Value , Animal Feed , Animals , Drosophila Proteins/genetics , Drosophila Proteins/physiology , Drosophila melanogaster/genetics , Dynamins/physiology , Entomology/instrumentation , Entomology/methods , Food Deprivation , Fructose/chemistry , Glucose/chemistry , Intestines/physiopathology , Ion Channels , Receptors, Cell Surface/physiology , Sodium-Glucose Transport Proteins/genetics , Sodium-Glucose Transport Proteins/physiology , Species Specificity , Stereoisomerism , TRPA1 Cation Channel , TRPC Cation Channels/physiology
18.
Stroke ; 45(8): 2480-4, 2014 Aug.
Article in English | MEDLINE | ID: mdl-25013021

ABSTRACT

BACKGROUND AND PURPOSE: Micro-computed tomography (mCT) offers high-resolution images, but it suffers from low contrast sensitivity and poor soft tissue contrast. We introduce a new mCT imaging technique with improved sensitivity for the dynamic spatial and temporal characterization of poststroke blood-brain barrier (BBB) dysfunction in small animals in vivo. METHODS: Transient middle cerebral artery occlusion was induced for 1 hour in 10- to 12-week-old C57BL/6 mice (n=35). At 4, 24, and 48 hours after ischemic stroke, serial in vivo mCT imaging was performed 5 minutes after intravenous infusion (n=3) or intracarotid infusion of iopromide (240 µL) for 5 minutes (n=32). After intravenous injection of 2% Evans blue, we performed ex vivo near-infrared fluorescent imaging of parenchymal Evans blue leakage, visual assessment of poststroke parenchymal hematoma, triphenyltetrazolium chloride staining of the brain tissue, and quantitative mapping of stroke-related brain lesions. RESULTS: Infarct-related BBB dysfunction could be demonstrated with intra-arterial but not with intravenous infusion of iopromide. Iopromide leakage across the dysfunctional BBB showed a monophasic (not biphasic) course for 48 hours after ischemic insult in both the parenchymal hematoma (n=5) and the non-parenchymal hematoma (n=24) groups, with relatively severe leakiness and greater hemispheric midline shift in animals with hemorrhage. Parenchymal staining on in vivo mCT overlapped with ex vivo fluorescent staining because of Evans blue. Multivariable analyses showed that midline shift and the amount of iopromide leakage at each of the 3 time points predicted the final infarct size at 48 hours. CONCLUSIONS: The new mCT BBB imaging technique, based on the intra-arterial infusion of clinically available iopromide, allows serial quantitative visualization of poststroke BBB dysfunction in mice, with high resolution and in a sensitive manner.


Subject(s)
Blood-Brain Barrier/diagnostic imaging , Brain Ischemia/diagnostic imaging , Infarction, Middle Cerebral Artery/diagnostic imaging , Stroke/diagnostic imaging , X-Ray Microtomography/methods , Animals , Brain/diagnostic imaging , Mice
19.
Prev Nutr Food Sci ; 19(4): 314-20, 2014 Dec.
Article in English | MEDLINE | ID: mdl-25580396

ABSTRACT

Flavor quality of Liriopis tuber tea that was made using a steaming process was studied by measuring changes in headspace volatile compounds. Headspace volatile compounds of the prepared samples were isolated, separated and identified by the combined system of purge & trap, automatic thermal desorber, gas chromatography, and mass selective detector. As steaming frequencies were increased, the area percent of aldehydes decreased from 32.01% to 3.39% at 1 and 9 steaming frequency times, respectively. However, furans and ketones increased from 18.67% to 33.86% and from 9.60% to 17.40% at 1 and 9 times, respectively. The savory flavor of Liriopis tuber tea was due to a decrease in aldehydes contributing a fresh flavor at the 1st steaming process and newly generated furans from nonenzymatic browning with repeated steaming frequencies. These results will provide basic information for quality control of the newly developed Liriopis tuber tea.

20.
BMC Infect Dis ; 14: 590, 2014 Nov 14.
Article in English | MEDLINE | ID: mdl-25891200

ABSTRACT

BACKGROUND: We estimated the nationwide burden of nosocomial S. aureus bloodstream infection (SA-BSI), a major cause of nosocomial infection, in South Korea. METHODS: To evaluate the nationwide incidence of nosocomial SA-BSI, cases of SA-BSI were prospectively collected from 22 hospitals with over 500 beds over 4?months. Data on patient-days were obtained from a national health insurance database containing the claims data for all healthcare facilities in South Korea. The additional cost of SA-BSI was estimated through a matched case?control study. The economic burden was calculated from the sum of the medical costs, the costs of caregiving and loss of productivity. RESULTS: Three hundred and thirty nine cases of nosocomial SA-BSI were included in the study: 254 cases of methicillin-resistant SA-BSI (MRSA-BSI) and 85 cases of methicillin-susceptible SA-BSI (MSSA-BSI). Death related to BSI occurred in 81 cases (31.9%) of MRSA-BSI and 12 cases (14.1%) of MSSA-BSI. The estimated incidence of nosocomial MRSA-BSI was 0.12/1,000 patient-days and that of nosocomial MSSA-BSI, 0.04/1,000 patient-days. The estimated annual cases of nosocomial BSI were 2,946 for MRSA and 986 for MSSA in South Korea. The additional economic burden per case of nosocomial SA-BSI was US $20,494 for MRSA-BSI and $6,914 for MSSA-BSI. Total additional annual cost of nosocomial SA-BSI was $67,192,559. CONCLUSION: In view of the burden of nosocomial SA-BSI, a national strategy for reducing nosocomial SA-BSI is urgently needed in South Korea.


Subject(s)
Bacteremia/epidemiology , Cross Infection/epidemiology , Staphylococcal Infections/epidemiology , Staphylococcus aureus/isolation & purification , Aged , Case-Control Studies , Cost of Illness , Databases, Factual , Female , Hospitals , Humans , Incidence , Male , Methicillin Resistance , Prospective Studies , Republic of Korea/epidemiology , Staphylococcus aureus/drug effects
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