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3.
Int J Biol Macromol ; 204: 274-283, 2022 Apr 15.
Article in English | MEDLINE | ID: mdl-35120942

ABSTRACT

Due to phase heterogeneity in semi-crystalline polymers, accurate determination of gas solubility has been a challenge. In this regard, PLA/CO2 was used as a case study to investigate the parameters governing formation of the rigid amorphous fraction (RAF) and its effect on the gas sorption behavior of the polymer. Six samples with different degrees of RAF were prepared through varying PLA tacticity and thermal history. Then, a gravimetric method involving a magnetic suspension balance and an in-house PVT visualization system was employed to experimentally determine the CO2 solubility at 70 °C under a pressure of 4.5 MPa. Furthermore, a theoretical CO2 solubility was calculated based on the Simha-Somcynski equation of state and was used in conjunction with the two-phase and three-phase models to describe the phase dependency of the gas solubility. The conventional two-phase model that considered the bulk amorphous phase consistently over-approximated the CO2 solubility compared to the measured data. On the other hand, the three-phase model that distinguished the rigid and the mobile amorphous phases well represented the experimental result. The analysis yielded CO2 solubility coefficients of 0.0375 ggas/gpoly for the RAF and 0.0817 ggas/gpoly for the mobile counterpart.


Subject(s)
Carbon Dioxide , Polyesters , Crystallization , Solubility , Thermodynamics
4.
Animals (Basel) ; 11(10)2021 Sep 30.
Article in English | MEDLINE | ID: mdl-34679877

ABSTRACT

Feeding condensed tannin (CT)-containing diets such as sericea lespedeza (Lespedeza cuneata) and reducing stress have been reported to improve meat quality and food safety in goats. In a completely randomized design with split-plot, thirty-six uncastrated male Spanish goats were assigned to 3 dietary treatments (n = 12/treatment): ground 'Serala' sericea lespedeza hay (SER), bermudagrass (Cynodon dactylon) hay (BG), or bermudagrass hay-dewormed goats (BG-DW; Control) at 75% of intake, with a corn-based supplementation (25%) for 8 weeks. Prior to slaughter, goats were either transported for 90 min to impose stress or held in pens. Basophil counts were lower (p < 0.01) in the SER group compared to BG or BG-DW groups suggesting a better anti-inflammatory capacity due to polyphenols in the SER diet. Compared to BG-DW group, cortisol level was higher (p < 0.05) and norepinephrine was lower (p < 0.05) in the SER group. The SER group had the lowest aerobic plate counts (APC) in both rumen and rectum (p < 0.01). Longissimus dorsi muscle initial pH was not affected by diet or stress. Feeding sericea hay to goats may have beneficial effects, such as enhanced antioxidant and anti-inflammatory properties during stress and reduced gut microbial counts, without changing meat quality characteristics.

5.
Int J Gynaecol Obstet ; 153(2): 322-329, 2021 May.
Article in English | MEDLINE | ID: mdl-33448028

ABSTRACT

OBJECTIVE: The primary aim was to compare the overall survival of women with unsuspected uterine malignancy (UUM) diagnosed after laparotomic versus laparoscopic hysterectomy for benign gynecologic diseases. The secondary aim was to evaluate the incidence of UUM. METHODS: A national health insurance database was analyzed from 2006 to 2010. RESULTS: From the database (24 million women annually), 157 232 women who received hysterectomy for benign diseases were extracted. These women were divided into a laparotomic group (n = 103 631) and a laparoscopic group (n = 53 601). The overall incidences of UUM, unsuspected endometrial cancer, and unsuspected uterine malignancy other than endometrial cancer (UUMOEC) were 0.66%, 0.46%, and 0.19%, respectively. Kaplan-Meier survival analysis and Cox regression analysis showed that the laparoscopic group was associated with more favorable overall survival than the laparotomic group, especially in UUMOEC (P < 0.001). CONCLUSION: In women with UUM diagnosed after hysterectomy for benign diseases, overall survival up to 7 years favors laparoscopy over laparotomy, especially in UUMOEC and the incidence of UUM is relatively low. However, considering the devastating effect of intraperitoneal dissemination of UUM, surgeons should fully explain this issue to patients preoperatively and try to avoid intraperitoneal spread of tumor cells intraoperatively.


Subject(s)
Endometrial Neoplasms/mortality , Hysterectomy/statistics & numerical data , Laparoscopy/statistics & numerical data , Uterine Neoplasms/mortality , Adult , Databases, Factual , Endometrial Neoplasms/diagnosis , Female , Humans , Incidence , Middle Aged , Republic of Korea , Retrospective Studies , Survival Analysis , Uterine Neoplasms/diagnosis
6.
Histopathology ; 76(5): 714-721, 2020 Apr.
Article in English | MEDLINE | ID: mdl-31841221

ABSTRACT

AIMS: Interaction between programmed death-1 ligand (PD-L1) and its receptor programmed death 1 (PD-1) on T cells inactivates antitumour immune responses. PD-L1 expression has been associated with poor prognosis in renal cell carcinoma (RCC) and predicts adverse outcome. This study was designed to evaluate the impact of PD-L1 expression and the immune microenvironment on the clinical outcome in Xp11 translocation renal cell carcinoma (TRCC) and, therefore, their potential relevance as prognostic biomarkers. METHODS AND RESULTS: The present retrospective analysis investigated expression of PD-L1 and immune cells CD8, CD4, CD3, forkhead box protein 3 (FoxP3) and PD-1 in TRCC compared to other types of RCC. FFPE specimens were collected between 2011 and 2017 from 311 patients who underwent nephrectomy at our institution for RCC. Specimens were immunostained for PD-L1, CD8, CD4, CD3, FoxP3 and PD-1, and an outcome analysis was conducted. PD-L1 expression rate was highest in TRCC (68%, 16 of 25), followed by mucinous tubular and spindle cell RCC and collecting duct carcinoma (33%, one of three), papillary RCC (27%, seven of 26), clear cell RCC (16%, 29 of 233), chromophobe RCC (11%, two of 18) and multilocular cystic RCC (0%, none of three). In TRCC, PD-L1 expression was associated with poor recurrence-free survival (RFS) (P = 0.041). The CD4high and FoxP3high groups showed a significantly shorter RFS (P = 0.05 and P = 0.031, respectively) compared to CD4low and FOXPlow groups. CONCLUSION: PD-L1 expression was higher in TRCC than in other types of RCC. High PD-L1 tumour cell expression and tumour infiltration by CD4+ and FoxP3+ immune cells were associated with poor RFS in TRCC.


Subject(s)
B7-H1 Antigen/biosynthesis , CD4-Positive T-Lymphocytes/immunology , Carcinoma, Renal Cell/immunology , Kidney Neoplasms/immunology , Lymphocytes, Tumor-Infiltrating/immunology , Adult , Aged , Aged, 80 and over , Carcinoma, Renal Cell/genetics , Carcinoma, Renal Cell/pathology , Chromosomes, Human, X/genetics , Female , Forkhead Transcription Factors/immunology , Humans , Kidney Neoplasms/genetics , Kidney Neoplasms/pathology , Male , Middle Aged , Prognosis , Retrospective Studies , Translocation, Genetic , Tumor Microenvironment/immunology
7.
ACS Appl Mater Interfaces ; 11(44): 41726-41735, 2019 Nov 06.
Article in English | MEDLINE | ID: mdl-31610650

ABSTRACT

Ideal dielectric materials for microelectronic devices should have high directionally tailored thermoconductivity with low dielectric constant and loss. Hexagonal boron nitride (hBN) with excellent thermal and dielectric properties shows a promise for the fabrication of thermoconductive dielectric polymer composites. Herein, a simple method for the fabrication of lightweight polymer/hBN composites with high directionally tailored thermoconductivity and excellent dielectric properties is presented. The solid polymer/hBN composites are manufactured by melt-compounding and injection molding. The porous composites are successfully manufactured in an injection molding process through supercritical fluid (SCF) foaming. X-ray tomography provides direct visualization of the internal microstructure and hBN orientation, leading to an in-depth understanding of the directionally dependent thermoconductivity of the polymer/hBN composite. Shear-induced orientation of hBN platelets in the solid HDPE/hBN composites leads to a significant anisotropic thermal conductivity. The solid HDPE/23.2 vol % hBN composites show an in-plane thermoconductivity as high as 10.1 W m-1 K-1, whereas the through-plane thermoconductivity is limited to 0.28 W m-1 K-1. However, the generation of a porous structure via SCF foaming imparts in situ exfoliation, random orientation, and interconnectivity of hBN platelets within the polymer matrix. This results in highly isotropic thermoconductivity with higher bulk thermal conductivity in the lightweight porous composites as compared to their solid counterparts. Furthermore, the electrically insulating composites developed in this study exhibit low dielectric constant and ultralow dielectric loss. Thus, this study presents a simple fabrication method to develop lightweight dielectric materials with tailored thermal conductivity for modern electronics.

8.
Anim Nutr ; 5(3): 278-285, 2019 Sep.
Article in English | MEDLINE | ID: mdl-31528730

ABSTRACT

The aim of this study was to determine the effects of tannin-rich peanut skin (PS) supplementation on growth performance, ruminal and blood metabolites, and carcass traits associated with internal parasite infection in meat goats under confined conditions. Twenty-one Kiko crossbred male goats were blocked by body weight (BW) and randomly assigned to one of 3 treatment groups. Experimental diets contained different levels of peanut (Arachis hypogaea) skin replacing alfalfa (Medicago sativa) pellets (ALP) in a control diet. Experimental treatments included: 30% ALP (control), 15% PS and 15% ALP, and 30% PS. Peanut skin was incorporated in the grain mix portion of the diets. Animals were fed once daily, and the intake was adjusted every 3 to 4 d. Each animal was each artificially infected with 5,000 larvae of the 3rd stage of barber's pole worm (Haemonchus contortus). Body weights, dry matter intake (DMI), and fecal samples for fecal egg counts (FEC) were taken at d 0, 12, 23, and 41. Rumen fluid and blood samples were collected at d 45. The performance period lasted 45 d and at the completion of the study, goats were harvested, and carcass characteristics, abomasal worm counts were measured. The results showed that DMI, BW, carcass traits, and meat color were not affected by PS supplementation, whereas average daily gain (ADG, P < 0.01), blood glucose (P < 0.001), phosphorus (P < 0.05), and cholesterol levels (P < 0.001) significantly increased with increasing levels of PS supplementation. There was a linear (P < 0.01) reduction in rumen acetate to propionate ratio, ammonia-nitrogen, FEC, and H. contortus worm counts, with increasing levels of PS supplementation. This study shows that PS supplementation up to 30% of the diet can improve ADG and rumen fermentation while reducing gastrointestinal parasite infection in meat goats.

9.
Front Comput Neurosci ; 11: 28, 2017.
Article in English | MEDLINE | ID: mdl-28487644

ABSTRACT

Most cortical inhibitory cell types exclusively express one of three genes, parvalbumin, somatostatin and 5HT3a. We conjecture that these three inhibitory neuron types possess distinct roles in visual contextual processing based on two observations. First, they have distinctive synaptic sources and targets over different spatial extents and from different areas. Second, the visual responses of cortical neurons are affected not only by local cues, but also by visual context. We use modeling to relate structural information to function in primary visual cortex (V1) of the mouse, and investigate their role in contextual visual processing. Our findings are three-fold. First, the inhibition mediated by parvalbumin positive (PV) cells mediates local processing and could underlie their role in boundary detection. Second, the inhibition mediated by somatostatin-positive (SST) cells facilitates longer range spatial competition among receptive fields. Third, non-specific top-down modulation to interneurons expressing vasoactive intestinal polypeptide (VIP), a subclass of 5HT3a neurons, can selectively enhance V1 responses.

10.
Int Wound J ; 13(5): 996-9, 2016 Oct.
Article in English | MEDLINE | ID: mdl-25091799

ABSTRACT

Fournier's gangrene is a type of necrotising fasciitis around the scrotum and perineum. Because of its aggressive nature, patients should be treated with broad-spectrum antibiotics and emergency, radical debridement during the acute phase. After recovering from the acute phase, reconstruction of the scrotal and perineal soft tissue defects is needed and is often challenging. Traditionally, various reconstruction methods have been used, including skin grafts, fasciocutaneous flaps and musculocutaneous flaps, each with its pros and cons. We successfully covered a wide scrotal defect using a superficial circumflex iliac artery perforator flap, which has not been previously reported for this indication. The design and operative technique are introduced in this study.


Subject(s)
Fasciitis, Necrotizing/surgery , Fournier Gangrene/surgery , Iliac Artery/transplantation , Perforator Flap/transplantation , Plastic Surgery Procedures/methods , Scrotum/surgery , Skin Transplantation/methods , Adult , Humans , Male , Middle Aged , Treatment Outcome
11.
J Neurosci ; 35(45): 15000-14, 2015 Nov 11.
Article in English | MEDLINE | ID: mdl-26558772

ABSTRACT

The dynamical behavior of the cortex is extremely complex, with different areas and even different layers of a cortical column displaying different temporal patterns. A major open question is how the signals from different layers and different brain regions are coordinated in a flexible manner to support function. Here, we considered interactions between primary auditory cortex and adjacent association cortex. Using a biophysically based model, we show how top-down signals in the beta and gamma regimes can interact with a bottom-up gamma rhythm to provide regulation of signals between the cortical areas and among layers. The flow of signals depends on cholinergic modulation: with only glutamatergic drive, we show that top-down gamma rhythms may block sensory signals. In the presence of cholinergic drive, top-down beta rhythms can lift this blockade and allow signals to flow reciprocally between primary sensory and parietal cortex. SIGNIFICANCE STATEMENT: Flexible coordination of multiple cortical areas is critical for complex cognitive functions, but how this is accomplished is not understood. Using computational models, we studied the interactions between primary auditory cortex (A1) and association cortex (Par2). Our model is capable of replicating interaction patterns observed in vitro and the simulations predict that the coordination between top-down gamma and beta rhythms is central to the gating process regulating bottom-up sensory signaling projected from A1 to Par2 and that cholinergic modulation allows this coordination to occur.


Subject(s)
Beta Rhythm/physiology , Cerebral Cortex/physiology , Cholinergic Neurons/physiology , Gamma Rhythm/physiology , Neural Networks, Computer , Signal Transduction/physiology , Humans , Neural Pathways/physiology
12.
Histopathology ; 67(4): 520-8, 2015 Oct.
Article in English | MEDLINE | ID: mdl-25786562

ABSTRACT

AIMS: From the viewpoint of histogenesis, lung adenocarcinoma can be subdivided into two groups: terminal respiratory unit (TRU) and non-TRU types. We recently reported a non-TRU type adenocarcinoma designated as ciliated adenocarcinoma (we now prefer central type adenocarcinoma). We suggest reasons that mucinous adenocarcinoma should encompass central type adenocarcinoma to represent its biological characteristics as non-TRU type adenocarcinoma. METHODS AND RESULTS: Mucin (MUC)5AC and MUC5B were expressed more significantly in non-TRU type adenocarcinoma (P < 0.01). Thirty-five (76.1%) and 45 cases (97.8%) of 46 non-TRU type adenocarcinoma showed positivity for MUC5AC and MUC5B. Twelve (7.6%) and eight (5.1%) cases of 157 TRU type adenocarainoma showed positivity for MUC5B and MUC5AC. NKX2-1 gene expression was measured with quantitative reverse transcription-polymerase chain reaction (qRT-PCR). ΔΔCt of NKX2-1 gene expression was 6.79 for TRU type adenocarcinoma and 0.6 for non-TRU type adenocarcinoma. Overall survival and disease-free survival were poorer in non-TRU type adenocarcinoma (P = 0.02 and P = 0.03). A multivariate test also showed that non-TRU type adenocarcinoma is an independent prognostic factor (P = 0.04). CONCLUSION: MUC5AC and MUC5B were specific makers for non-TRU adenocarcinoma, including both central type adenocarcinoma and mucinous adenocarcinoma. We suggest that non-TRU type adenocarcinoma presents a poorer prognosis, so it should be regarded separately from TRU type adenocarcinoma.


Subject(s)
Adenocarcinoma, Mucinous/pathology , Biomarkers, Tumor/analysis , Lung Neoplasms/pathology , Mucin 5AC/biosynthesis , Mucin-5B/biosynthesis , Adenocarcinoma, Mucinous/classification , Adenocarcinoma, Mucinous/mortality , Aged , Disease-Free Survival , Female , Humans , Immunohistochemistry , Kaplan-Meier Estimate , Lung Neoplasms/classification , Lung Neoplasms/mortality , Male , Middle Aged , Mucin 5AC/analysis , Mucin-5B/analysis , Prognosis , Proportional Hazards Models , Real-Time Polymerase Chain Reaction
13.
ACS Appl Mater Interfaces ; 6(23): 21131-40, 2014 Dec 10.
Article in English | MEDLINE | ID: mdl-25437647

ABSTRACT

Effective removal of oils from water is of global significance for environmental protection. In this study, we investigate the hydrophobicity and oleophilicity of open-cell polymer foams prepared in a continuous and scalable extrusion process. The material used to prepare the open-cell foams is a fibrillar blend of polypropylene (PP) and polytetrafluoroethylene (PTFE). Scanning electron microscopy (SEM) images of the morphology of the PP/PTFE fibrillar blend reveal that the PTFE has a fibrillar morphology in the PP matrix. SEM micrograph of the extruded foam shows the formation of an interconnected open-cell structure. Using nitrogen pycnometry, the open-cell content is estimated to be 97.7%. A typical bulk density of the open-cell foam is measured to be about 0.07 g cm(-3) corresponding to a void fraction of 92%. Thus, a large three-dimensional space is made available for oil storage. A drop of water on the cross-section of the extruded open-cell foam forms a contact angle of 160° suggesting that the open-cell foam exhibits superhydrophobicity. The open-cell foam can selectively absorb various petroleum products, such as octane, gasoline, diesel, kerosene, light crude oil, and heavy crude oil from water and the uptake capacities range from about 5 to 24 g g(-1). The uptake kinetics can be enhanced by exposing the open-cell foam to high intensity ultrasound which increases the surface porosity of the thin, impervious, foam "skin" layer. The reusability of the foam can be improved by using a matrix polymer which demonstrates superior elastic properties and prevents the foams from undergoing a large permanent deformation upon compression to "squeeze out" the oil. For example, when the PP homopolymer matrix is replaced with a PP random copolymer, the permanent deformation for 10 compressive cycles is reduced from about 30% to 10%. To the best of our knowledge, these PP-based open-cell foams outperform PP-based absorbents conventionally used for oil-spill cleanup applications such as nonwoven PP fibers or melt-blown PP pads.

14.
Hear Res ; 312: 128-42, 2014 Jun.
Article in English | MEDLINE | ID: mdl-24721001

ABSTRACT

A listener's capacity to discriminate between sounds is related to the amount of acoustic variability that exists between these sounds. However, a full understanding of how this natural variability impacts neural activity and behavior is lacking. Here, we tested monkeys' ability to discriminate between different utterances of vocalizations from the same acoustic class (i.e., coos and grunts), while neural activity was simultaneously recorded in the anterolateral belt region (AL) of the auditory cortex, a brain region that is a part of a pathway that mediates auditory perception. Monkeys could discriminate between coos better than they could discriminate between grunts. We also found AL activity was more informative about different coos than different grunts. This difference could be attributed, in part, to our finding that coos had more acoustic variability than grunts. Thus, intrinsic acoustic variability constrained the discriminability of AL spike trains and the ability of rhesus monkeys to discriminate between vocalizations.


Subject(s)
Auditory Cortex/physiology , Auditory Perception/physiology , Behavior, Animal/physiology , Macaca mulatta/physiology , Vocalization, Animal/physiology , Action Potentials/physiology , Animals , Electrodes, Implanted , Microelectrodes , Psychomotor Performance/physiology , ROC Curve , Species Specificity
15.
Ther Deliv ; 5(3): 265-75, 2014 Mar.
Article in English | MEDLINE | ID: mdl-24592953

ABSTRACT

BACKGROUND: Domperidone is an antidopaminergic drug that facilitates a function of the digestive smooth muscle. Depending on the Biopharmaceutical Classification System, domperidone is classified as class II with poor solubility and high permeability. METHOD/RESULTS: Solid dispersions were prepared by spray-drying with a polymer. The characterization of prepared solid dispersions was analyzed by scanning electron microscope, Fourier transform infrared spectroscopy, x-ray diffraction and differential scanning calorimeter. In vitro dissolution behavior was carried out in gastric juice (pH 1.2) and these results were compared with pure domperidone (active pharmaceutical ingredient). The dissolution rate was improved due to the influence of polymers. Stability assays were conducted by the same pre-experiment. Storage conditions of the solid dispersions were as follows: 25°C relative humidity 25% and 65°C relative humidity 80%. CONCLUSION: In this study, the goal is to improve the dissolution rate of domperidone by solid dispersions and to confirm stability of the prepared solid dispersions. It suggests that the content of polymers added in solid dispersions can affect the dissolution behavior and change dissolution rate of drug.


Subject(s)
Desiccation , Domperidone/chemistry , Dopamine Antagonists/chemistry , Aerosols , Calorimetry, Differential Scanning , Chemistry, Pharmaceutical , Crystallography, X-Ray , Drug Carriers , Drug Stability , Drug Storage , Gastric Juice/chemistry , Humidity , Hydrogen-Ion Concentration , Kinetics , Microscopy, Electron, Scanning , Povidone/chemistry , Solubility , Spectroscopy, Fourier Transform Infrared , Technology, Pharmaceutical/methods , Temperature
16.
Am J Pathol ; 183(5): 1488-1497, 2013 Nov.
Article in English | MEDLINE | ID: mdl-24001475

ABSTRACT

Adenosine in the normal kidney significantly elevates in response to cellular damage. The renal A3 adenosine receptor (A3AR) is up-regulated under stress, but the therapeutic effects of A3AR antagonists on chronic kidney disease are not fully understood. The present study examined the effect of LJ-1888 [(2R,3R,4S)-2-[2-chloro-6-(3-iodobenzylamino)-9H-purine-9-yl]-tetrahydrothiophene-3,4-diol], a newly developed potent, selective, species-independent, and orally active A3AR antagonist, on unilateral ureteral obstruction (UUO)-induced renal fibrosis. Pretreatment with LJ-1888 inhibited UUO-induced fibronectin and collagen I up-regulation in a dose-dependent manner. Masson's trichrome staining confirmed that LJ-1888 treatment effectively reduced UUO-induced interstitial collagen accumulation. Furthermore, delayed administration of LJ-1888 showed an equivalent therapeutic effect on tubulointerstitial fibrosis to that of losartan. Small-interfering A3AR transfection effectively inhibited transforming growth factor-ß1 (TGF-ß1)-induced fibronectin and collagen I up-regulation in proximal tubular cells similar to LJ-1888, confirming that the renoprotective effect of LJ-1888 resulted from A3AR blockade. UUO- or TGF-ß1-induced c-Jun N-terminal kinase and extracellular signal-regulated kinase phosphorylation decreased significantly after LJ-1888 administration. A3AR blockade reduced UUO- or TGF-ß1-induced up-regulation of lysyl oxidase, which induces cross-linking of extracellular matrix, suggesting that LJ-1888 may also regulate extracellular matrix accumulation via post-translational regulation. In conclusion, the present data demonstrate that the A3AR antagonist, LJ-1888, blocked the development and attenuated the progression of renal fibrosis, and they suggest that LJ-1888 may become a new therapeutic modality for renal interstitial fibrosis.


Subject(s)
Adenosine A3 Receptor Antagonists/therapeutic use , Adenosine/therapeutic use , Kidney Diseases/drug therapy , Kidney Diseases/prevention & control , Kidney Tubules, Proximal/pathology , Receptor, Adenosine A3/metabolism , Thiophenes/therapeutic use , Ureteral Obstruction/complications , Adenosine/pharmacology , Adenosine A3 Receptor Antagonists/administration & dosage , Adenosine A3 Receptor Antagonists/pharmacology , Animals , Collagen Type I/genetics , Collagen Type I/metabolism , Epithelial-Mesenchymal Transition/drug effects , Extracellular Matrix/drug effects , Extracellular Matrix/metabolism , Extracellular Signal-Regulated MAP Kinases/metabolism , Fibronectins/genetics , Fibronectins/metabolism , Fibrosis , Gene Expression Regulation/drug effects , JNK Mitogen-Activated Protein Kinases/metabolism , Kidney Diseases/enzymology , Kidney Diseases/pathology , Kidney Tubules, Proximal/drug effects , Kidney Tubules, Proximal/enzymology , Kidney Tubules, Proximal/metabolism , Male , Mice , Mice, Inbred C57BL , Phosphorylation/drug effects , Protein-Lysine 6-Oxidase/metabolism , RNA, Messenger/genetics , RNA, Messenger/metabolism , Rats , Rats, Sprague-Dawley , Signal Transduction/drug effects , Smad Proteins/metabolism , Thiophenes/pharmacology , Transforming Growth Factor beta1/pharmacology , Ureteral Obstruction/enzymology , Ureteral Obstruction/pathology
18.
PLoS Comput Biol ; 9(8): e1003164, 2013.
Article in English | MEDLINE | ID: mdl-23950699

ABSTRACT

Cortical rhythms have been thought to play crucial roles in our cognitive abilities. Rhythmic activity in the beta frequency band, around 20 Hz, has been reported in recent studies that focused on neural correlates of attention, indicating that top-down beta rhythms, generated in higher cognitive areas and delivered to earlier sensory areas, can support attentional gain modulation. To elucidate functional roles of beta rhythms and underlying mechanisms, we built a computational model of sensory cortical areas. Our simulation results show that top-down beta rhythms can activate ascending synaptic projections from L5 to L4 and L2/3, responsible for biased competition in superficial layers. In the simulation, slow-inhibitory interneurons are shown to resonate to the 20 Hz input and modulate the activity in superficial layers in an attention-related manner. The predicted critical roles of these cells in attentional gain provide a potential mechanism by which cholinergic drive can support selective attention.


Subject(s)
Beta Rhythm/physiology , Models, Neurological , Action Potentials/physiology , Animals , Computational Biology , Computer Simulation , Macaca , Neurons/physiology , Pyramidal Cells/physiology
19.
J Physiol ; 590(13): 3129-39, 2012 Jul 01.
Article in English | MEDLINE | ID: mdl-22570374

ABSTRACT

A comprehensive understanding of the neural mechanisms of cognitive function requires an understanding of how neural representations are transformed across different scales of neural organization: from within local microcircuits to across different brain areas. However, the neural transformations within the local microcircuits are poorly understood. Particularly, the role that two main cell classes of neurons in cortical microcircuits (i.e. pyramidal neurons and interneurons) have in auditory behaviour and cognition remains unknown. In this study, we tested the hypothesis that pyramidal cells and interneurons in the auditory cortex play a differential role in auditory categorization. To test this hypothesis, we recorded single-unit activity from the auditory cortex of rhesus monkeys while they categorized speech sounds. Based on the spike-waveform shape, a neuron was classified as either a narrow-spiking putative interneuron or a broad-spiking putative pyramidal neuron. We found that putative interneurons and pyramidal neurons in the auditory cortex differentially coded category information: interneurons were more selective for auditory categories than pyramidal neurons. These differences between cell classes may be an essential property of the neural computations underlying auditory categorization within the microcircuitry of the auditory cortex.


Subject(s)
Auditory Cortex/physiology , Interneurons/physiology , Pyramidal Cells/physiology , Acoustic Stimulation , Action Potentials , Animals , Macaca mulatta , Male
20.
J Sep Sci ; 34(21): 2967-74, 2011 Nov.
Article in English | MEDLINE | ID: mdl-21898818

ABSTRACT

A mixture of polyphenol components was isolated from the fruits of C. annuum L. cv. Cupra, C. annuum L. cv. Orange glory, and C. annuum L. cv. ST4712 (CLST), via 70% methanol extraction followed by column chromatography over silica gel. The polyphenol components of the mixture were analyzed via HPLC-MS/MS and compared with the reported data. Three cinnamic acid derivatives and five flavonoid components in the fruits of the three varieties were identified for the first time in this study. The antioxidant activity and anticancer effect of the polyphenol mixtures of the three fruits were determined. The antioxidant and anticancer activities of CLST were substantially higher than those of C. annuum L. cv. Cupra and C. annuum L. cv. Orange glory. The high activities of CLST were attributed to the much higher concentration of quercetin derivatives in CLST.


Subject(s)
Antineoplastic Agents/analysis , Antineoplastic Agents/pharmacology , Antioxidants/analysis , Antioxidants/pharmacology , Capsicum/chemistry , Polyphenols/analysis , Polyphenols/pharmacology , Cell Line, Tumor , Cell Proliferation/drug effects , Cell Survival/drug effects , Chromatography, High Pressure Liquid , Dose-Response Relationship, Drug , Drug Screening Assays, Antitumor , Fruit/chemistry , HeLa Cells , Humans , Molecular Structure , Stereoisomerism , Structure-Activity Relationship , Tandem Mass Spectrometry
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