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1.
Phys Rev Lett ; 133(11): 113802, 2024 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-39331981

RESUMO

Non-Hermitian systems have attracted much interest in recent decades, driven partly by the existence of exotic spectral singularities, known as exceptional points (EPs), where the dimensionality of the system evolution operator is reduced. Among various intriguing applications, the discovery of EPs has suggested the potential for implementing a symmetric mode switch, when encircling them in a system parameter space. However, subsequent theoretical and experimental works have revealed that dynamical encirclement of EPs invariably results in asymmetric mode conversion; namely, the mode switching depends only on the winding direction but not on the initial state. This chirality arises from the failure of adiabaticity due to the complex spectrum of non-Hermitian systems. Although the chirality revealed has undoubtedly made a significant impact in the field, a realization of the originally sought symmetric adiabatic passage in non-Hermitian systems with EPs has since been elusive. In this work, we bridge this gap and theoretically demonstrate that adiabaticity, and therefore a symmetric state transfer, is achievable when dynamically winding around an EP. This becomes feasible by specifically choosing a trajectory in the system parameter space along which the corresponding evolution operator attains a real spectrum. Our findings, thus, offer a promise for advancing various wave manipulation protocols in both quantum and classical domains.

2.
Science ; 384(6700): 1122-1126, 2024 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-38843319

RESUMO

The control of thermal radiation by shaping its spatial and spectral emission characteristics plays a key role in many areas of science and engineering. Conventional approaches to tailoring thermal emission using metamaterials are hampered both by the limited spatial resolution of the required subwavelength material structures and by the materials' strong absorption in the infrared. In this work, we demonstrate an approach based on the concept of topology. By changing a single parameter of a multilayer coating, we were able to control the reflection topology of a surface, with the critical point of zero reflection being topologically protected. The boundaries between subcritical and supercritical spatial domains host topological interface states with near-unity thermal emissivity. These topological concepts enable unconventional manipulation of thermal light for applications in thermal management and thermal camouflage.

3.
Light Sci Appl ; 13(1): 143, 2024 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-38918396

RESUMO

Quantum heat engines and refrigerators are open quantum systems, whose dynamics can be well understood using a non-Hermitian formalism. A prominent feature of non-Hermiticity is the existence of exceptional points (EPs), which has no counterpart in closed quantum systems. It has been shown in classical systems that dynamical encirclement in the vicinity of an EP, whether the loop includes the EP or not, could lead to chiral mode conversion. Here, we show that this is valid also for quantum systems when dynamical encircling is performed in the vicinity of their Liouvillian EPs (LEPs), which include the effects of quantum jumps and associated noise-an important quantum feature not present in previous works. We demonstrate, using a Paul-trapped ultracold ion, the first chiral quantum heating and refrigeration by dynamically encircling a closed loop in the vicinity of an LEP. We witness the cycling direction to be associated with the chirality and heat release (absorption) of the quantum heat engine (quantum refrigerator). Our experiments have revealed that not only the adiabaticity breakdown but also the Landau-Zener-Stückelberg process play an essential role during dynamic encircling, resulting in chiral thermodynamic cycles. Our observations contribute to further understanding of chiral and topological features in non-Hermitian systems and pave a way to exploring the relation between chirality and quantum thermodynamics.

4.
Br Poult Sci ; 65(4): 455-464, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38598261

RESUMO

1. Tibial dyschondroplasia (TD) is a skeletal disorder in broilers that has financial implications, necessitating dietary modifications to reduce the prevalence of this disease. This study explored how arginine silicate inositol complex (ASI) supplementation affected tibial growth plate (TGP) and overall bone health in broilers with manganese (Mn) deficiency-induced TD.2. A total of 240 broiler chicks were divided into four groups, each consisting of 60 birds (15 replicates of four broilers each) as follows: i) Control, with 60 mg Mn per kg of diet; ii) ASI, with 60 mg Mn and 1 g ASI per kg of diet; iii) TD, with 22 mg Mn per kg of diet, and iv) TD+ASI, with 22 mg Mn and 1 g ASI per kg of diet.3. It was found that ASI supplementation increased tibial bone length in Mn-deficient TD broilers (p = 0.007). There was no Mn x ASI interaction for other bone morphometry variables (p > 0.05). However, both tibial bone mineral content and density were affected by Mn and ASI (p < 0.05). With ASI supplementation, serum bone-specific alkaline phosphatase and osteocalcin levels were elevated in the TD+ASI group compared to the TD group (p < 0.001). In the TD group, osteoprotegerin (OPG) levels in the TGP decreased compared to the control groups (p < 0.001).4. In contrast, ASI supplementation in the TD broilers counteracted the decrease in OPG compared to TD broilers without ASI supplementation (p < 0.001). The Mn level and ASI supplementation significantly influenced the OPG/receptor activator of the nuclear factor-κB ligand ratio (p < 0.001).5. In conclusion, the results demonstrated that inclusion of ASI in broiler diets could enhance bone formation variables by controlling OPG levels in the TGP, potentially serving as an effective method to decrease the occurrence of TD.


Assuntos
Ração Animal , Arginina , Galinhas , Dieta , Suplementos Nutricionais , Inositol , Manganês , Osteocondrodisplasias , Doenças das Aves Domésticas , Tíbia , Animais , Galinhas/crescimento & desenvolvimento , Manganês/administração & dosagem , Manganês/metabolismo , Ração Animal/análise , Suplementos Nutricionais/análise , Osteocondrodisplasias/veterinária , Osteocondrodisplasias/metabolismo , Tíbia/efeitos dos fármacos , Dieta/veterinária , Arginina/administração & dosagem , Inositol/administração & dosagem , Masculino , Densidade Óssea/efeitos dos fármacos , Silicatos/administração & dosagem , Distribuição Aleatória
5.
Nat Commun ; 14(1): 2076, 2023 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-37045822

RESUMO

Nontrivial spectral properties of non-Hermitian systems can lead to intriguing effects with no counterparts in Hermitian systems. For instance, in a two-mode photonic system, by dynamically winding around an exceptional point (EP) a controlled asymmetric-symmetric mode switching can be realized. That is, the system can either end up in one of its eigenstates, regardless of the initial eigenmode, or it can switch between the two states on demand, by simply controlling the winding direction. However, for multimode systems with higher-order EPs or multiple low-order EPs, the situation can be more involved, and the ability to control asymmetric-symmetric mode switching can be impeded, due to the breakdown of adiabaticity. Here we demonstrate that this difficulty can be overcome by winding around exceptional curves by additionally crossing diabolic points. We consider a four-mode [Formula: see text]-symmetric bosonic system as a platform for experimental realization of such a multimode switch. Our work provides alternative routes for light manipulations in non-Hermitian photonic setups.

7.
Nat Commun ; 13(1): 7351, 2022 11 29.
Artigo em Inglês | MEDLINE | ID: mdl-36446776

RESUMO

Accurate assessment of cell stiffness distribution is essential due to the critical role of cell mechanobiology in regulation of vital cellular processes like proliferation, adhesion, migration, and motility. Stiffness provides critical information in understanding onset and progress of various diseases, including metastasis and differentiation of cancer. Atomic force microscopy and optical trapping set the gold standard in stiffness measurements. However, their widespread use has been hampered with long processing times, unreliable contact point determination, physical damage to cells, and unsuitability for multiple cell analysis. Here, we demonstrate a simple, fast, label-free, and high-resolution technique using acoustic stimulation and holographic imaging to reconstruct stiffness maps of single cells. We used this acousto-holographic method to determine stiffness maps of HCT116 and CTC-mimicking HCT116 cells and differentiate between them. Our system would enable widespread use of whole-cell stiffness measurements in clinical and research settings for cancer studies, disease modeling, drug testing, and diagnostics.


Assuntos
Holografia , Pinças Ópticas , Estimulação Acústica , Biofísica , Diferenciação Celular
8.
Artigo em Inglês | MEDLINE | ID: mdl-35894799

RESUMO

Thoracic computed tomography angiography revealed a filling defect with an internal air density in the lower lobar branch of the left pulmonary artery accompanied by pleural fluid, in a patient who applied with sudden onset chest pain and dyspnoea. The filling defect remained stable after anticoagulant treatment. No progression or complications were observed in 5-year follow-up. In pulmonary embolism that does not resolve despite adequate treatment, non-thrombotic sources, particularly foreign body, should be considered.


Assuntos
Embolia Pulmonar , Angiografia/métodos , Anticoagulantes/efeitos adversos , Seguimentos , Humanos , Artéria Pulmonar/diagnóstico por imagem , Embolia Pulmonar/complicações , Embolia Pulmonar/etiologia
9.
Science ; 376(6589): 184-188, 2022 04 08.
Artigo em Inglês | MEDLINE | ID: mdl-35389774

RESUMO

The topological structure associated with the branch point singularity around an exceptional point (EP) can provide tools for controlling the propagation of light. Through use of graphene-based devices, we demonstrate the emergence of EPs in an electrically controlled interaction between light and a collection of organic molecules in the terahertz regime at room temperature. We show that the intensity and phase of terahertz pulses can be controlled by a gate voltage, which drives the device across the EP. Our electrically tunable system allows reconstruction of the Riemann surface associated with the complex energy landscape and provides topological control of light by tuning the loss imbalance and frequency detuning of interacting modes. Our approach provides a platform for developing topological optoelectronics and studying the manifestations of EP physics in light-matter interactions.

10.
Malays Orthop J ; 16(3): 44-49, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36589385

RESUMO

Introduction: Bigliani classification is used for determination of acromial morphology, but poor inter-observer reliability has been reported on conventional radiographs. This study aims to assess inter- and intra-observer reliability using magnetic resonance imaging (MRI). Materials and methods: Forty consecutive patients diagnosed with subacromial impingement syndrome were included to study. All subjects underwent standard shoulder MRI scan and acromial shape was evaluated by nine observers of different level of expertise (three attending surgeons, three senior orthopaedic residents and three radiologists). A second set of evaluation was performed in order to assess intra-observer reproducibility. Kappa (κ) coefficient analyses both for interobserver reliability and intra-observer reproducibility were then performed. Results: Overall inter-observer agreement among nine observers was fair (κ=0.323). κ values for all 4 individual types ranged from 0.234 to 0.720 with highest agreement for type 4 and lowest agreement for type 3. Second evaluation did not result with an increase of inter-observer agreement (κ=0.338, fair). The κ coefficients for intra-observer reproducibility of nine observers ranged from 0.496 to 0.867. Overall intra-observer reproducibility was substantial. Comparison of inter- and intra-observer reliability among three groups showed no significant difference (p=0.92 and 0.22, respectively). Conclusion: Results showed that MRI did not show superior reliability compared to conventional radiographs. Moreover, inter- and intra-observer agreement did not differ between observers of different level of expertise. Findings of present study suggest that despite a sophisticated imaging modality like MRI, Bigliani's classification apparently lacks accuracy and additional criteria, or different assessment methods are required to assess acromial morphology for clinical guidance.

11.
SAR QSAR Environ Res ; 32(10): 769-792, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34530651

RESUMO

The hybrid method of the Electron-Conformational Genetic Algorithm (EC-GA) was used to determine the pharmacophore groups and to estimate anticancer activity in isatin derivatives using a robust 4D-QSAR software (EMRE). To build the model, each compound is represented by a set of conformers rather than a single conformation. The Electron Conformational Matrix of Congruity (ECMC) is composed via EMRE software. Electron Conformational Submatrix of Activity (ECSA) was calculated by the comparison of these matrices. Genetic algorithm was used to select important variables to predict theoretical activity. The model with the best seven parameters produced satisfactory results. The E statistics technique was applied to the generated EC-GA model to evaluate the individual contribution of each of the descriptors on biological activity. The r2 and q2 values of the training set compounds were found to be 0.95 and 0.93, respectively. Because no previous 4D-QSAR studies on isatin derivatives have been conducted, this study is important in the development of new isatin derivatives. In this study, 27 isatin derivatives whose activities were estimated using the hybrid EC-GA method were also investigated through molecular docking and molecular dynamics simulations for their BCL-2 inhibitory activity.


Assuntos
Antineoplásicos/farmacologia , Isatina/análogos & derivados , Isatina/farmacologia , Proteínas Proto-Oncogênicas c-bcl-2/química , Relação Quantitativa Estrutura-Atividade , Antineoplásicos/química , Isatina/química , Conformação Molecular , Simulação de Acoplamento Molecular , Proteínas Proto-Oncogênicas c-bcl-2/antagonistas & inibidores
12.
Br Poult Sci ; 62(2): 227-234, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33085516

RESUMO

1. This work examined the effects of purified lycopene (LYC) supplementation or a source of LYC as tomato powder (TP) on productive performance, egg yolk cholesterol levels as well as gene expression related to mechanism and regulation of cholesterol.2. One hundred and fifty laying hens (Lohman LSL, hybrid) were randomly divided into one of three treatments, with 10 replicates of five hens per cage, totalling 50 hens per treatment. The hens were fed either a standard diet (control) or a standard diet supplemented with 20 mg purified lycopene/kg diet (LYC) or an equal amount of lycopene-containing tomato powder (TP) for 12 weeks.3. Feed consumption, egg production, and feed efficiency remained similar among treatments (P ≥ 0.27). Supplementing lycopene, either as a purified form or in TP, increased the levels of serum and egg yolk lycopene and reduced serum and egg yolk cholesterol concentrations (P < 0.001). Supplementation in either form decreased gene expression for intestinal NPC1L1, MTP, ACAT2, hepatic SREBP1c, ACLY, and LXRα but increased hepatic ABCG5 and ABCG8 (P < 0.001).4. The results of the present work revealed that egg yolk cholesterol metabolism is regulated by the modulation of a group of genes, particularly with LYC supplementation.


Assuntos
Galinhas , Gema de Ovo , Ração Animal/análise , Animais , Galinhas/genética , Colesterol , Dieta/veterinária , Suplementos Nutricionais/análise , Feminino , Expressão Gênica , Licopeno , Óvulo
13.
Bratisl Lek Listy ; 121(6): 450-454, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32484711

RESUMO

OBJECTIVE: Obesity induced by a high fat diet is associated with chronic up-regulation of inflammatory cytokines which stimulate osteoclast activity and bone resorption. However, the role of high-fat diet on bone-implant connectivity has not been studied in detail. In this study, we investigated whether a high-fat diet (HFD) affects bone implant connection (BIC) in periimplant bone. METHODS: Twenty female Sprague Dawley rats were divided in two groups: 1) Control rats were fed with normal chow and titanium implants were integrated into tibial bones at the end of 3rd month and no treatment was applied 2) HFD group; rats were fed a high-fat diet (42 % of calories as fat), then the titanium implants were integrated into tibial bones at the end 3rd month. Following surgical integration of the implants, the rats were fed with control and HFD diets for 3 months. After the 6 months experimental period all rats were sacrificed and the implants and surrounded bone tissues were collected and the BIC was assessed histomorphometrically after the non-decalcifiing histological methods. Bone implant connection was detected with the ratio of the implant surface directly connected with the peri-implant bone tissues to the total implant surface length. RESULTS: Histologic analysis showed that HFD was not impaired BIC (p>0.05). CONCLUSION: In conclusion, within the limitation of this research, HFD did not effect the BIC rat tibias (Tab. 2, Fig. 2, Ref. 26). Text in PDF www.elis.sk.


Assuntos
Transplante Ósseo , Dieta Hiperlipídica , Osseointegração , Animais , Osso e Ossos , Feminino , Ratos , Ratos Sprague-Dawley , Propriedades de Superfície , Titânio
14.
Malays Orthop J ; 13(1): 45-48, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31001384

RESUMO

Aneurysmal bone cysts rather than local aggressive lesions of the bone which may arise in any part of the axial or appendicular skeleton. Although several theories are available in the literature, the pathogenesis is still conflicting. We report an exceptional case of an aneurysmal bone cyst in the distal femur of a female cerebral palsy patient who underwent bilateral distal femoral derotational osteotomy and plate-screw fixation operations when she was 11 years old. Twenty-four months after the operation, radiographs showed a cystic lesion in the distal portion of the right femur around the osteotomy site. The diagnosis of Aneurysmal Bone Cyst (ABC) was made and the lesion was treated by curettage with cement application. After 36 months of follow-up, there was no recurrence. This is the first case reported in literature which raises the possibility that an osteotomy could be a cause in the development of an aneurysmal bone cyst.

15.
Br Poult Sci ; 60(3): 195-201, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29355388

RESUMO

1. The objective of this study was to determine muscle structure and gene expression in pectoralis major (p. major) muscle of broilers in response to deep pectoral myopathy (DPM) induction. 2. A total of 160 chickens from slow- and fast-growing broilers were raised under same conditions. Half of the broilers from each strain were encouraged to wing flap when they reached 2800 g body weight. Pectoralis minor (p. minor) muscle of the broilers was inspected for the occurrence of DPM and p. major samples were collected from broilers with or without DPM. The muscle fibre area and number, capillary number and the signalling pathways of vascular development (vascular endothelial growth factor A, VEGFA) and muscle contraction regulation (actin alpha 1, ACTA1; myosin light chain kinase 2, MYLK2 and ATPase Ca+2 transporting gene 1, ATP2A1) were studied in p. major muscle. 3. DPM induction increased fibre area of p. major muscle with a greater rate in the slow-growing strain compared with fast-growing line. Although the capillary number was higher in slow-growing compared with fast-growing broilers, in the case of DPM induction, the number of capillaries was similar between strains. 4. Expression of VEGFA, MYLK2 and ATP2A1 was greater in slow- than in fast-growing broilers. DPM induction increased expression of ACTA1, VEGFA and ATP2A1 in p. major muscle of broilers from both strains; however, MYLK2 expression was downregulated. 5. Changes in capillary density and expression of VEGFA found in the p. major muscle of broilers with DPM suggest increased blood flow to increase oxygen availability. The upregulation of ATP2A1 by DPM induction could be attributable to alterations in calcium ion transportation from the cytoplasm into the sarcoplasmic reticulum. 6. The results are evidence of changes in muscle structure and gene expression pathways in p. major muscle of broilers with DPM.


Assuntos
Proteínas Aviárias/genética , Galinhas , Expressão Gênica , Doenças Musculares/veterinária , Músculos Peitorais/química , Doenças das Aves Domésticas/fisiopatologia , Animais , Proteínas Aviárias/metabolismo , Doenças Musculares/genética , Doenças Musculares/fisiopatologia , Músculos Peitorais/fisiopatologia , Doenças das Aves Domésticas/genética
16.
Science ; 359(6379): 995-996, 2018 03 02.
Artigo em Inglês | MEDLINE | ID: mdl-29496870
17.
Poult Sci ; 97(4): 1298-1305, 2018 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-29365168

RESUMO

This experiment was conducted to compare the effect of the supplemental chromium (Cr) form on performance, egg quality, and metabolic profile in laying hens exposed to heat stress (HS). Laying hens (n = 1800; 16-wk-old; Lohmann LSL-Lite) were kept in cages in temperature-controlled rooms at either 22 ± 2°C for 24 h/d (thermoneutral, TN) or 34 ± 2°C for 8 h/d, from 08:00 to 17:00 h, followed by 22°C for 16 h (HS) for 12 wks. Hens reared under both environmental conditions were fed 1 of 3 diets: a basal diet and the basal diet supplemented with either 1.600 mg of chromium-picolinate (CrPic, 12.43% Cr) or 0.788 mg of chromium-histidinate (CrHis, 25.22% Cr) per kg of diet, delivering 200 µg elemental Cr per kg diet. Data were analyzed by 2-way ANOVA. Exposure to HS caused decreases in feed intake (P < 0.0001), egg production (P < 0.0001), egg weight (P < 0.0001), eggshell weight (P < 0.0009), eggshell thickness (P < 0.0001), eggshell strength (P < 0.0001), and Haugh unit (P < 0.0001), deterioration in feed conversion ratio (P < 0.0001), increases in serum glucose and cholesterol concentrations (P < 0.0001 for both), decreases in serum and egg yolk Cr concentrations (P < 0.0001 for both), and decreases in serum Na (P < 0.002) and K (P < 0.01) concentrations. Both Cr sources were equally effective in alleviating performance variables under the HS condition. However, neither Cr sources alleviated deteriorations in egg quality parameters and serum electrolytes. Both Cr sources decreased serum glucose and cholesterol concentrations and increased serum and egg yolk Cr concentrations under the HS condition. In conclusion, HS adversely affected laying performance, egg quality, and metabolic profile. Both CrPic and CrHis partially alleviated the adverse effect of HS on these parameters. Inclusion of either Cr source could be a part of nutritional management strategies to overcome the adverse effects of HS performance and metabolic profile in laying hens.


Assuntos
Galinhas/fisiologia , Cromo/metabolismo , Resposta ao Choque Térmico/efeitos dos fármacos , Metaboloma/efeitos dos fármacos , Óvulo/efeitos dos fármacos , Ração Animal/análise , Animais , Cromo/administração & dosagem , Dieta/veterinária , Suplementos Nutricionais/análise , Feminino , Óvulo/fisiologia
18.
Cell Mol Biol (Noisy-le-grand) ; 63(10): 93-98, 2017 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-29096748

RESUMO

In this study, the effect of the supplemental organic chromium (Cr) forms on the expression of ovarian orexin(hypocretin), glucose transporters (GLUTs), heat shock proteins (HSPs) andnuclear factor-kappaB (NF-κB)were investigated in laying hens (HS). Laying hens (n=1800; 16-wk-old; Lohmann LSL-Lite) were allocated to 6 random groups according to a 2 × 3 factorial trial scheme with two different environmental temperatures [Thermoneutral (TN groups; at either 22±2 °C 24 h/d)  and heat stress (HS groups; at 34±2 °C for 8 h/d, 08:00 to 17:00 h, followed by 22°C for 16 h for a period of 12 wks)], andhens reared under both environmental conditions were fed either a basal diet or the basal diet supplemented with 1.600 mg of chromium-picolinate (CrPic, 12.43% Cr) and 0.788 mg of chromium-histidinate (CrHis, 25.22% Cr) per kg of diet, delivering 200 µg elemental Cr per kg diet. HS groups showed decreased levels of orexin and GLUTs(GLUT1, GLUT4), and increased NFκB, HSP60, HSP70 and HSP90 levels compared to the TN groups in ovarian tissue of hens (P < 0.0001 for all).However, dietary chromium supplementation (CrPic-CrHis) increasedorexin and GLUTs levels and significantly reduced the NF-κB and HSPs levels making them closer to those of thermoneutral group (P < 0.0001).In conclusion, CrPic and CrHis showed supported the relief and treatment of stress complications.


Assuntos
Galinhas/metabolismo , Proteínas Facilitadoras de Transporte de Glucose/metabolismo , Histidina/análogos & derivados , Orexinas/metabolismo , Compostos Organometálicos/farmacologia , Ovário/metabolismo , Ácidos Picolínicos/farmacologia , Regulação para Cima/efeitos dos fármacos , Animais , Suplementos Nutricionais , Feminino , Proteínas Facilitadoras de Transporte de Glucose/genética , Proteínas de Choque Térmico/metabolismo , Histidina/farmacologia , NF-kappa B/metabolismo , Orexinas/genética , Ovário/efeitos dos fármacos , Estresse Fisiológico , Temperatura
19.
Poult Sci ; 96(12): 4317-4324, 2017 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-29053811

RESUMO

This experiment was conducted to investigate effects of the organic complex form of supplemental chromium (Cr) on performance, oxidative stress markers, and serum profile in broilers exposed to heat stress (HS). A total of 1,200 10-day-old boilers (Ross-308) was divided into one of the 6 treatments (2 environmental temperatures x 3 diets with different Cr forms). The birds were kept in temperature-controlled rooms at either 22 ± 2°C 24 h/d (thermoneutral, TN group) or 34 ± 2°C for 8 h/d, 08:00 to 17:00 h, followed by 22°C for 16 h (HS group) and fed either a basal diet (C) or the basal diet supplemented with Cr (200 µg/kg) through 1.600 mg of CrPic (12.43% Cr) and 0.788 mg of CrHis (25.22% Cr). Feed intake and body weight were recorded weekly. After cervical dislocation, liver samples were harvested to analyze Cr concentration and glucose transporter-2,4 (GLUT-2,4) expression. The breast meat also was sampled for the concentration of Cr and expressions of nuclear factor erythroid 2-related factor 2 (Nrf2) and nuclear factor kappa B (NF-κB). Data were analyzed by 2-way ANOVA. Heat stress caused depressions in feed intake (12.1%) and weight gain (21.1%) as well as elevations in feed conversion (11.2%) and abdominal fat (32.8%). It was also associated with depletion of Cr reserves and increases in serum concentrations of glucose, cholesterol, creatine, and enzymes. Exposure to HS was accompanied by suppression of the expressions of Nrf2 and GLUT-2 in muscle and GLUT-4 in the liver and amplification of the expression of NF-κB in muscle. Both Cr sources partially alleviated detrimental effects of HS on performance and metabolic profile. The efficacy of Cr as CrHis was more notable than Cr as CrPic, which could be attributed to higher bioavailability. In conclusion, CrHis can be added into the diet of broilers during hot seasons to overcome deteriorations in performance and wellbeing related to oxidative stress.


Assuntos
Galinhas/fisiologia , Cromo/metabolismo , Histidina/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Ração Animal/análise , Animais , Proteínas Aviárias/metabolismo , Galinhas/sangue , Galinhas/crescimento & desenvolvimento , Cromo/administração & dosagem , Dieta/veterinária , Suplementos Nutricionais/análise , Feminino , Proteínas Facilitadoras de Transporte de Glucose/metabolismo , Histidina/administração & dosagem , Masculino , Músculos/efeitos dos fármacos , Músculos/metabolismo , Fatores de Transcrição/metabolismo
20.
Eur Rev Med Pharmacol Sci ; 21(7): 1627-1634, 2017 04.
Artigo em Inglês | MEDLINE | ID: mdl-28429342

RESUMO

OBJECTIVE: In this study, the diagnostic value of serum endothelin-1 (ET-1) levels and the therapeutic effects of bosentan have been investigated in an experimental appendicitis rat model. MATERIALS AND METHODS: Twenty-one male Sprague-Dawley rats were chosen for the study. The rats were allocated into three groups as follows: Group 1 (control, n = 7), Group 2 (appendicitis, n = 7), and Group 3 (bosentan treatment, n = 7). At the 6th hour of the experiment, Groups 1 and 2 received 2 ml saline, and group 3 received 30 mg/kg bosentan intraperitoneally. At the 24th postoperative hour, all rats were sacrificed and evaluated histopathologically to score the severity of appendicitis. The plasma malondialdehyde, reduced and total glutathione levels, serum, and appendiceal tissue ET-1 levels were evaluated. RESULTS: In this study, we found that the ET-1 levels were significantly increased with appendicitis (p = 0.018). The administration of bosentan can statistically significantly both decrease the histopathologic injury in the inflamed appendix and increase the serum total glutathione levels (p = 0.002). CONCLUSIONS: The increase in plasma ET-1 levels may have a diagnostic value of acute appendicitis. We believe that manifestations that occur during the acute phase of appendicitis may be reduced with the administration of bosentan, which may also help prevent complications.


Assuntos
Apendicite , Antagonistas dos Receptores de Endotelina/farmacologia , Endotelina-1/sangue , Sulfonamidas/farmacologia , Animais , Apendicite/sangue , Apendicite/tratamento farmacológico , Bosentana , Masculino , Ratos , Ratos Sprague-Dawley
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