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1.
Radiography (Lond) ; 27(4): 1110-1117, 2021 Nov.
Article de Anglais | MEDLINE | ID: mdl-34092495

RÉSUMÉ

INTRODUCTION: Lateral radiography of the knee joint is frequently performed; however, the retake rate is high owing to positioning errors. Therefore, in this study, to reduce the required number and time of image retakes, we developed a system that can classify the tilting directions of lateral knee radiographs and evaluated the accuracy of the proposed method. METHODS: Using our system, the tilting directions of a lateral knee radiographs were classified into four direction categories. The system was developed by training the DCNN based on 50 cases of Raysum images and tested on three types test dataset; ten more cases of Raysum images, one case of flexed knee joint phantom images and 14 rejected knee joint radiographs. To train a deep convolutional neural network (DCNN), we employed Raysum images created via three-dimensional (3D) X-ray computed tomography (CT); 11 520 Raysum images were created from 60 cases of 3D CT data by changing the projection angles. Thereby, we obtained pseudo images attached with correct labels that are essential for training. RESULTS: The overall accuracy on each test dataset was 88.5 ± 7.0% (mean ± standard deviation), 81.4 ± 11.2%, and 73.3 ± 9.2%. The larger the tilting degree of the knee joint, the higher the classification accuracy. CONCLUSION: DCNN could classify the tilting directions of a knee joint from lateral knee radiographs. Using Raysum images made it possible to facilitate creating dataset for training DCNN. The possibility was indicated for using support system of lateral knee radiographs. IMPLICATIONS FOR PRACTICE: The system may also reduce the burden on patients and increase the work efficiency of radiological technologists.


Sujet(s)
, Tomodensitométrie , Humains , Fantômes en imagerie , Radiographie
2.
J Nutr Health Aging ; 24(5): 512-517, 2020.
Article de Anglais | MEDLINE | ID: mdl-32346690

RÉSUMÉ

OBJECTIVES: Swallowing function is critical for continuing oral feeding to prevent frailty in older adults. In this study, we investigated the impact of tongue pressure and pulmonary function on the nutritional status of older adults. DESIGN, SETTING, PARTICIPANTS: This cross-sectional study was conducted in Kitakyushu, Japan from August 2017 to November 2018. Fifty-two residents aged >65 years of age from three nursing care insurance facilities in Kitakyushu City, Japan were recruited. MEASUREMENTS: Oral health status, swallowing function, nutritional status using a mini nutritional assessment short form (MNA-SF), cognitive function, activities of daily living, peak expiratory flow rate (PEFR) for pulmonary function, and tongue pressure were assessed. The associations between nutritional status and the above factors were analysed using a logistic regression model. RESULTS: Participants were divided into two groups: well-nourished group (MNA-SF ≤12) and undernutrition group (MNA-SF <12). Multivariate logistic regression analysis revealed that the correlations of PEFR [odds ratio (OR) = 0.23, 95% confidence interval (CI) = 0.23-0.89 p=0.033) and tongue pressure (OR = 0.88, 95% CI = 0.88-0.99, p=0.029) remained significant even after adjustment with possible confounders. CONCLUSION: Maximum tongue pressure and PEFR in older adults were significantly associated with their nutritional status. These findings suggest that maintaining oral and pulmonary function may be a preventive factor against a decrease in the nutritional status of older frail adults.


Sujet(s)
Évaluation de l'état nutritionnel , État nutritionnel/physiologie , Débit expiratoire de pointe/physiologie , Langue/physiopathologie , Sujet âgé , Sujet âgé de 80 ans ou plus , Études transversales , Femelle , Évaluation gériatrique , Humains , Japon , Mâle , Maisons de repos
3.
Sci Adv ; 5(9): eaaw1164, 2019 09.
Article de Anglais | MEDLINE | ID: mdl-31579819

RÉSUMÉ

Modeling of postseismic deformation following great earthquakes has revealed the viscous structure of the mantle and the frictional properties of the fault interface. However, for giant megathrust events, viscoelastic flow and afterslip mechanically interplay with each other during the postseismic period. We explore the role of afterslip and viscoelastic relaxation and their interaction in the aftermath of the 2011 M w (moment magnitude) 9.0 Tohoku earthquake based on a detailed model analysis of the postseismic deformation with laterally varying, experimentally constrained, rock rheology. Mechanical coupling between viscoelastic relaxation and afterslip notably modifies both the afterslip distribution and surface deformation. Thus, we highlight the importance of addressing mechanical coupling for long-term studies of postseismic relaxation, especially in the context of the geodynamics of the Japan trench across the seismic cycle.

4.
Bone Joint J ; 101-B(5): 559-564, 2019 May.
Article de Anglais | MEDLINE | ID: mdl-31039001

RÉSUMÉ

AIMS: The use of vitamin E-infused highly crosslinked polyethylene (HXLPE) in total knee prostheses is controversial. In this paper we have compared the clinical and radiological results between conventional polyethylene and vitamin E-infused HXLPE inserts in total knee arthroplasty (TKA). PATIENTS AND METHODS: The study included 200 knees (175 patients) that underwent TKA using the same total knee prostheses. In all, 100 knees (77 patients) had a vitamin E-infused HXLPE insert (study group) and 100 knees (98 patients) had a conventional polyethylene insert (control group). There were no significant differences in age, sex, diagnosis, preoperative knee range of movement (ROM), and preoperative Knee Society Score (KSS) between the two groups. Clinical and radiological results were evaluated at two years postoperatively. RESULTS: Differences in postoperative ROM and KSS were not statistically significant between the study and control groups. No knee exhibited osteolysis, aseptic loosening, or polyethylene failure. Additionally, there was no significant difference in the incidence of a radiolucent line between the two groups. One patient from the study group required irrigation and debridement, due to deep infection, at six months postoperatively. CONCLUSION: Clinical results were comparable between vitamin E-infused HXLPE inserts and conventional polyethylene inserts at two years after TKA, without any significant clinical failure. Cite this article: Bone Joint J 2019;101-B:559-564.


Sujet(s)
Arthroplastie prothétique de genou/instrumentation , Prothèse de genou/effets indésirables , Polyéthylène/administration et posologie , Conception de prothèse/méthodes , Vitamine E/administration et posologie , Sujet âgé , Arthroplastie prothétique de genou/effets indésirables , Arthroplastie prothétique de genou/méthodes , Réactifs réticulants , Femelle , Humains , Articulation du genou/chirurgie , Mâle , Adulte d'âge moyen , Période postopératoire , Conception de prothèse/effets indésirables , Amplitude articulaire
5.
Sci Rep ; 8(1): 10423, 2018 Jul 12.
Article de Anglais | MEDLINE | ID: mdl-30002478

RÉSUMÉ

In nature, protons (H+) play an important role in biological activities such as in mitochondrial ATP synthesis, which is driven by a H+ gradient across the inner membrane, or in the activation of acid sensing ion channels in neuron cells. Bioprotonic devices directly interface with the H+ concentration (pH) to facilitate engineered interactions with these biochemical processes. Here we develop a H+ biotransducer that changes the pH in a mitochondrial matrix by controlling the flow of H+ between a conductive polymer of sulfonated polyaniline and solution. We have successfully modulated the rate of ATP synthesis in mitochondria by altering the solution pH. Our H+ biotransducer provides a new way to monitor and modulate pH dependent biological functions at the interface between the electronic devices and biological materials.


Sujet(s)
Adénosine triphosphate/biosynthèse , Bioingénierie/méthodes , Mitochondries/métabolisme , Protons , Transducteurs , Animaux , Concentration en ions d'hydrogène , Microélectrodes , Myocarde/cytologie , Suidae
7.
Andrologia ; 50(1)2018 Feb.
Article de Anglais | MEDLINE | ID: mdl-28295471

RÉSUMÉ

This study examined whether feeding hydroalcoholic extract of Lepidium meyenii (maca) to 8-week-old (sexually maturing) or 18-week-old (mature) male rats for more than a half year affects serum testosterone concentration and testosterone production by Leydig cells cultured with hCG, 22R-hydroxycholesterol or pregnenolone. Testosterone concentration was determined in the serum samples obtained before and 6, 12, 18 and 24 weeks after the feeding, and it was significantly increased only at the 6 weeks in the group fed with the maca extract to maturing rats when it was compared with controls. Testosterone production by Leydig cells significantly increased when cultured with hCG by feeding the maca extract to maturing rats for 27 weeks (35 weeks of age) and when cultured with 22R-hydroxycholesterol by feeding it to mature rats for 30 weeks (48 weeks of age). Overall testosterone production by cultured Leydig cells decreased to about a half from 35 to 48 weeks of age. These results suggest that feeding the maca extract for a long time to male rats may enhance the steroidogenic ability of Leydig cells to alleviate its decline with ageing, whereas it may cause only a transient increase in blood testosterone concentration in sexually maturing male rats.


Sujet(s)
Vieillissement/effets des médicaments et des substances chimiques , Lepidium , Cellules de Leydig/effets des médicaments et des substances chimiques , Extraits de plantes/pharmacologie , Testostérone/biosynthèse , Vieillissement/métabolisme , Animaux , Gonadotrophine chorionique/pharmacologie , Hydroxycholestérols/pharmacologie , Cellules de Leydig/métabolisme , Mâle , Prégnénolone/pharmacologie , Rats , Testostérone/sang
8.
Reprod Domest Anim ; 53(1): 270-273, 2018 Feb.
Article de Anglais | MEDLINE | ID: mdl-29110347

RÉSUMÉ

This study examined the effects of treatment with U0126, which inhibits MAPK by inhibiting MAPK kinase, during the first 2 hr of in vitro maturation on bovine developmental competence and on gap junction (GAPJ) communication between the oocyte and cumulus cells. The percentage of oocytes developing to the blastocyst stage in the group treated with 5 µM U0126 (28%) was significantly higher than that in controls (15%, p < .05), while that in the group treated with 10 µM U0126 (18%) was not. Breakdown of the GAPJs was delayed in the group treated with 5 µM U0126 when compared to controls, as estimated by immunohistochemical examination of connexin 43, which is a primary constituent of the GAPJs. These results indicate that treatment with 5 µM U0126 during in vitro maturation delays GAPJ breakdown and improves bovine oocyte developmental competence.


Sujet(s)
Butadiènes/pharmacologie , Bovins , Techniques de maturation in vitro des ovocytes/médecine vétérinaire , Mitogen-Activated Protein Kinase Kinases/antagonistes et inhibiteurs , Nitriles/pharmacologie , Ovocytes/effets des médicaments et des substances chimiques , Animaux , Blastocyste/effets des médicaments et des substances chimiques , Communication cellulaire , Connexine 43/métabolisme , Cellules du cumulus/physiologie , Femelle , Fécondation in vitro/médecine vétérinaire , Jonctions communicantes/physiologie , Immunohistochimie , Techniques de maturation in vitro des ovocytes/méthodes
9.
Andrologia ; 49(10)2017 Dec.
Article de Anglais | MEDLINE | ID: mdl-28261840

RÉSUMÉ

Although feeding diets containing the extract powder of Lepidium meyenii (maca), a plant growing in Peru's Central Andes, increases serum testosterone concentration associated with enhanced ability of testosterone production by Leydig cells in male rats, changes in testicular steroidogenesis-related factors by the maca treatment are not known. This study examined the effects of maca on testicular gene expressions for luteinizing hormone receptor, steroidogenic acute regulatory protein and steroidogenic enzymes. Eight-week-old male rats were given the diets with or without (control) the maca extract powder (2%) for 6 weeks, and mRNA levels were determined by reverse transcription quantitative real-time PCR. The results showed that the testicular mRNA level of HSD3B1 (3ß-hydroxysteroid dehydrogenase; 3ß-HSD) increased by the treatment, whereas the levels of the other factors examined did not change. These results suggest that increased expression of 3ß-HSD gene may be involved in the enhanced steroidogenic ability by the maca treatment in rat testes.


Sujet(s)
17-Hydroxysteroid dehydrogenases/génétique , Expression des gènes/effets des médicaments et des substances chimiques , Lepidium , Extraits de plantes/pharmacologie , Testicule/effets des médicaments et des substances chimiques , 17-Hydroxysteroid dehydrogenases/métabolisme , Animaux , Cellules de Leydig/effets des médicaments et des substances chimiques , Mâle , Phosphoprotéines/génétique , Phosphoprotéines/métabolisme , Rats , Récepteur LH/génétique , Récepteur LH/métabolisme , Spermatogenèse/effets des médicaments et des substances chimiques , Testicule/métabolisme
10.
Eur J Neurol ; 24(5): 673-679, 2017 05.
Article de Anglais | MEDLINE | ID: mdl-28251765

RÉSUMÉ

BACKGROUND AND PURPOSE: Few studies have examined why some patients with dementia stop attending medical consultations. We conducted a retrospective study to investigate factors associated with discontinuous clinic attendance. METHODS: Participants were 988 patients with dementia from university hospital (UH) clinics and affiliated local hospital (LH) clinics. We compared continuous and discontinuous attenders on cognitive and affective functions and activities of daily living (ADL), and also compared UH and LH patients (UH: continuous, n = 176; discontinuous, n = 207; LH: continuous, n = 418; discontinuous, n = 187). RESULTS: The total annual rate of discontinuation was 8.0%, and the mean period of attendance before discontinuation was 2.2 ± 2.4 years (UH, 2.8 ± 3.0; LH, 1.5 ± 1.3, P < 0.01). Scores for the Mini-Mental State Examination, Hasegawa Dementia Scale - Revised, Geriatric Depression Scale, apathy scale, Abe's behavioral and psychological symptoms of dementia (BPSD) score, and ADL were significantly worse in the discontinuous group than the continuous group for both UH and LH patients (P < 0.01). The best predictor of discontinuation was ADL decline (UH and LH) and Abe's BPSD score (UH). The most common reason for discontinuation was returning to the family doctor (39.1% for UH), and cessation of hospital attendance at their own discretion (35.3% for LH). CONCLUSIONS: We identified the main reasons for discontinuation of attendance as returning to the family doctor and cessation of hospital attendance at their own discretion. The best predictors of discontinuation were ADL decline and worsening BPSD. There were significant differences in discontinuation between UH and LH patients with dementia.


Sujet(s)
Activités de la vie quotidienne , Démence/rééducation et réadaptation , Hôpitaux/statistiques et données numériques , Patients en consultation externe/statistiques et données numériques , Observance par le patient/statistiques et données numériques , Abandon des soins par les patients/statistiques et données numériques , Sujet âgé , Sujet âgé de 80 ans ou plus , Femelle , Humains , Mâle , Études rétrospectives
11.
Org Biomol Chem ; 15(17): 3568-3570, 2017 May 03.
Article de Anglais | MEDLINE | ID: mdl-28345721

RÉSUMÉ

The structural basis for the intracellular delivery of OSW-1 is investigated using fluorescent derivatives of OSW-1 and its closely related congeners. Despite the large differences in activity, all the fluorescent probes are found to translocate across the plasma membrane to the ER and Golgi apparatus. This observation suggests that the glycosylated cholestane moiety plays an important role in the cell internalization and intracellular localization property of OSW-1.


Sujet(s)
Cholesténones/composition chimique , Cholesténones/métabolisme , Colorants fluorescents/composition chimique , Colorants fluorescents/métabolisme , Espace intracellulaire/métabolisme , Saponines/composition chimique , Saponines/métabolisme , Transport biologique , Cellules HeLa , Humains
13.
Chem Commun (Camb) ; 53(2): 462, 2016 12 22.
Article de Anglais | MEDLINE | ID: mdl-27957581

RÉSUMÉ

Correction for 'Synthesis of a fluorescent photoaffinity probe of OSW-1 by site-selective acylation of an inactive congener and biological evaluation' by K. Sakurai et al., Chem. Commun., 2017, DOI: .

14.
J Comput Chem ; 37(10): 886-95, 2016 Apr 15.
Article de Anglais | MEDLINE | ID: mdl-26748592

RÉSUMÉ

We simulate the formation of a BN fullerene from an amorphous B cluster at 2000 K by quantum mechanical molecular dynamics based on the density-functional tight-binding method. We run 30 trajectories 200 ps in length, where N atoms are supplied around the target cluster, which is initially an amorphous B36 cluster. Most of the incident N atoms are promptly incorporated into the target cluster to form B-N-B bridges or NB3 pyramidal local substructures. BN fullerene formation is initiated by alternating BN ring condensation. Spontaneous atomic rearrangement and N2 dissociation lead to the construction of an sp(2) single-shelled structure, during which the BN cluster undergoes a transition from a liquid-like to a solid-like state. Continual atomic rearrangement and sporadic N2 dissociation decrease the number of defective rings in the BN cluster and increase the number of six-membered rings, forming a more regular shell structure. The number of four-membered rings tends to remain constant, and contributes to more ordered isolated-tetragon-rule ring placement.

15.
Eur J Neurol ; 23(1): 196-200, 2016 Jan.
Article de Anglais | MEDLINE | ID: mdl-26768678

RÉSUMÉ

BACKGROUND AND PURPOSE: A novel TYPE of prion disease associated mainly with autonomic-sensory polyneuropathy was reported by us previously. METHODS: Here the autopsy pathology for patient 1 (the sister) and the clinical characteristics of her younger brother (patient 2) are newly reported. Polymerase chain reaction based restriction fragment length polymorphism analysis of the prion protein gene (PRNP) was performed on both patients and their father (normal control). RESULTS: Polymerase chain reaction based restriction fragment length polymorphism analysis revealed a 2-bp deletion (CT) in codon 178 that causes an additional variable 25 amino acids at the C terminal, from the mutation site to the premature stop codon at codon 203, in both patients 1 and 2 but not in their father. The autopsy of patient 1 showed remarkable prion protein (PrP) deposits in the sympathetic ganglion and peripheral nerves, correlated to her severe autonomic sensory failure. PrP deposits were also found in the central nervous system and peripheral organs such as the heart, lung, stomach, jejunum, ileum, colon, urinary bladder and adrenal gland. The symptoms and biopsy findings of patient 2 were nearly the same as those reported previously for patient 1. His cognitive function was well preserved, but autonomic functions were severely impaired. His biopsied samples showed PrP deposits in the sural nerve and nerve plexuses of the stomach and colon. CONCLUSION: The present unique 2-bp deletion (CT) in codon 178 induced a 'PrP systemic deposition disease' such as pan-autonomic failure, sensory neuropathy and mild cognitive impairment with a specific pathology.


Sujet(s)
Maladies à prions/génétique , Prions/génétique , Adulte , Codon , Issue fatale , Femelle , Humains , Mâle , Pedigree , Polymorphisme de restriction , Maladies à prions/anatomopathologie , Maladies à prions/physiopathologie , Protéines prion
16.
Eur J Neurol ; 23(2): 339-45, 2016 Feb.
Article de Anglais | MEDLINE | ID: mdl-26493280

RÉSUMÉ

BACKGROUND AND PURPOSE: The influence of metabolic syndrome (MetS) on cognitive and affective functions in patients with Alzheimer's disease (AD) was examined. METHODS: A total of 570 AD patients were divided into two subgroups depending on waist circumference (WC) (normal versus achieving Japanese diagnostic criteria of MetS). Afterwards, the AD control subgroup was defined as those normal WC patients with no vascular risk factors (VRFs). The AD with MetS (AD-MetS) subgroup was defined as the MetS WC group who had two or more VRFs to qualify as having MetS. Cognitive and affective functions, insulin resistance, vascular endothelial function and white matter changes between AD-MetS and AD controls were compared. RESULTS: Scores on the Mini-Mental State Examination, Hasegawa Dementia Score-Revised, Frontal Assessment Battery and Montreal Cognitive Assessment were worse in the AD-MetS group than in AD controls, but the difference was not significant. Some analyses were conducted twice, once including all patients and once including only late-elderly patients. Scores on the Geriatric Depression Scale were found to be significantly higher for AD-MetS than for AD controls (all ages, late-elderly), as were those for apathy (late-elderly). Furthermore, both the homeostasis model assessment of insulin resistance and reactive hyperemia index scores were significantly worse in AD-MetS than in AD controls, whilst white matter changes showed a tendency to be worse. CONCLUSIONS: Greater cognitive and affective decline occurs in patients with AD-MetS than in those without. Further, insulin resistance and vascular endothelial dysfunction are strongly correlated with AD-MetS before pathological white matter changes can be observed.


Sujet(s)
Maladie d'Alzheimer/anatomopathologie , Maladie d'Alzheimer/physiopathologie , Syndrome métabolique X/anatomopathologie , Syndrome métabolique X/physiopathologie , Substance blanche/anatomopathologie , Sujet âgé , Sujet âgé de 80 ans ou plus , Maladie d'Alzheimer/épidémiologie , Apathie/physiologie , Comorbidité , Dépression/épidémiologie , Dépression/physiopathologie , Femelle , Humains , Japon/épidémiologie , Mâle , Syndrome métabolique X/épidémiologie
17.
Andrologia ; 48(3): 347-54, 2016 Apr.
Article de Anglais | MEDLINE | ID: mdl-26174043

RÉSUMÉ

Although Lepidium meyenii (maca), a plant growing in Peru's central Andes, has been traditionally used for enhancing fertility and reproductive performance in domestic animals and human beings, effects of maca on reproductive organs are still unclear. This study examined whether feeding the hydroalcoholic extract powder of maca for 6 weeks affects weight of the reproductive organs, serum concentrations of testosterone and luteinising hormone (LH), number and cytoplasmic area of immunohistochemically stained Leydig cells, and steroidogenesis of cultured Leydig cells in 8-week-old male rats. Feeding the extract powder increased weight of seminal vesicles, serum testosterone level and cytoplasmic area of Leydig cells when compared with controls. Weight of prostate gland, serum LH concentration and number of Leydig cells were not affected by the maca treatment. The testosterone production by Leydig cells significantly increased when cultured with 22R-hydroxycholesterol or pregnenolone and tended to increase when cultured with hCG by feeding the extract powder. The results show that feeding the hydroalcoholic extract powder of maca for 6 weeks increases serum testosterone concentration associated with seminal vesicle stimulation in male rats, and this increase in testosterone level may be related to the enhanced ability of testosterone production by Leydig cells especially in the metabolic process following cholesterol.


Sujet(s)
Lepidium , Cellules de Leydig/effets des médicaments et des substances chimiques , Extraits de plantes/pharmacologie , Testostérone/sang , Animaux , Cellules cultivées , Oestradiol/sang , Cellules de Leydig/cytologie , Cellules de Leydig/métabolisme , Hormone lutéinisante/sang , Mâle , Taille d'organe/effets des médicaments et des substances chimiques , Prostate/effets des médicaments et des substances chimiques , Rats , Rat Wistar , Testostérone/biosynthèse
18.
J Neurol Sci ; 350(1-2): 14-7, 2015 Mar 15.
Article de Anglais | MEDLINE | ID: mdl-25662676

RÉSUMÉ

In addition to cognitive impairment, behavioral and psychological symptoms of dementia (BPSD) are another important aspect of most dementia patients. This study was designed for a new simple assessment of BPSD. We first employed a clinical survey for the local community with sending an inquiry letter to all members (n=129) of dementia caregiver society, and then attempted to create a new BPSD score for dementia with 10 BPSD items. This new simple BPSD score was compared to a standard-detailed BPSD score neuropsychiatric inventory (NPI) for a possible correlation (n=792) and a time to complete (n=136). Inter-rater reliability was examined comparing scores between main and second caregivers (n=70) for AD. Based on the clinical survey for local caregivers, a new BPSD score for dementia (ABS, Abe's BPSD score) was newly created, in which each BPSD item was allotted by an already-weighted score (maximum 1-9) based on the frequency and severity, and was finalized with taking temporal occurrences into account. ABS was filled by the main caregiver with a full score of 44, was well correlated with NPI (r=0.716, **p<0.01) in 792 AD patients (age 78.6 ± 7.0 years, MMSE 19.0 ± 5.9), and took a shorter time as only 56.8 ± 38.8s (**p<0.01) than NPI score (132.7 ± 94.0 s) with 136 AD patients. A high inter-rater reliability was obtained (r=0.964, **p<0.01) with a little smaller score (0.877 time) of ABS in secondary than the main caregivers. ABS provides a new simple and quick test for BPSD assessment, with a good correlation to NPI but a shorter time, and with a high inter-rater reliability. Thus ABS is useful for evaluating BPSD for mild to moderate dementia patients.


Sujet(s)
Symptômes comportementaux/diagnostic , Symptômes comportementaux/psychologie , Démence/diagnostic , Démence/psychologie , Tests neuropsychologiques/normes , Indice de gravité de la maladie , Sujet âgé , Sujet âgé de 80 ans ou plus , Femelle , Humains , Mâle , Adulte d'âge moyen , Reproductibilité des résultats
19.
Poult Sci ; 94(4): 722-7, 2015 Apr.
Article de Anglais | MEDLINE | ID: mdl-25681609

RÉSUMÉ

The ileal apical sodium-dependent bile acid cotransporter (ASBT) plays an essential role in the absorption of bile acids from intestinal lumina. ASBT cDNA has been cloned from mammalian and fish species, and the primary structure of the protein and expression properties of the mRNA have been characterized. In this study, we identified chicken ASBT mRNA by cDNA cloning. Chicken ASBT cDNA consisted of 91 bp of the 5'-untranslated region, 1,083 bp of the coding region, and 1,896 bp of the 3'-untranslated region. The cDNA encoded a protein of 360 amino acids showing significant sequence identity with mammalian and fish ASBT. The amino acid residues known to participate in the functions of mammalian ASBT were conserved in chicken ASBT. Real-time polymerase chain reaction analysis revealed that chicken ASBT mRNA was expressed at markedly higher levels in the ileum and proximal colon/rectum, relatively lower levels in the kidney, and very low levels in the jejunum and cecum. Expression levels in the ileum markedly increased after hatching, reached the highest levels on day 7 posthatching, and then decreased to adult levels. A similar expression pattern was observed in the proximal colon/rectum except for the significant decrease from day 7 posthatching to day 21 posthatching. These results suggest that chicken ASBT functions as a bile acid transporter in the ileum and proximal colon/rectum, particularly during the early posthatching period.


Sujet(s)
Protéines aviaires/génétique , Poulets/génétique , Transporteurs d'anions organiques sodium-dépendants/génétique , Symporteurs/génétique , Séquence d'acides aminés , Animaux , Protéines aviaires/métabolisme , Séquence nucléotidique , Poulets/métabolisme , Femelle , Données de séquences moléculaires , Spécificité d'organe , Transporteurs d'anions organiques sodium-dépendants/métabolisme , ARN messager/génétique , ARN messager/métabolisme , Réaction de polymérisation en chaine en temps réel/médecine vétérinaire , Symporteurs/métabolisme
20.
Phys Rev Lett ; 112(2): 026401, 2014 Jan 17.
Article de Anglais | MEDLINE | ID: mdl-24484030

RÉSUMÉ

Using exact numerical techniques, we investigate the nature of excitonic (electron-hole) bound states and the development of exciton coherence in the one-dimensional half-filled extended Falicov-Kimball model. The ground-state phase diagram of the model exhibits, besides band-insulator and staggered orbital ordered phases, an excitonic insulator (EI) with power-law correlations. The criticality of the EI state shows up in the von Neumann entropy. The anomalous spectral function and condensation amplitude provide the binding energy and coherence length of the electron-hole pairs which, on their part, point towards a Coulomb interaction driven crossover from BCS-like electron-hole pairing fluctuations to tightly bound excitons. We show that while a mass imbalance between electrons and holes does not affect the location of the BCS-BEC crossover regime, it favors staggered orbital ordering to the disadvantage of the EI. Within the Bose-Einstein condensation (BEC) regime, the quasiparticle dispersion develops a flat valence-band top, in accord with the experimental finding for Ta2NiSe5.

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