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2.
Molecules ; 27(3)2022 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-35164149

RESUMO

Arginine kinase (AK) plays a crucial role in the survival of Daphnia magna, a water flea and a common planktonic invertebrate sensitive to water pollution, owing to the production of bioenergy. AK from D. magna (DmAK) has four highly conserved histidine residues, namely, H90, H227, H284, and H315 in the amino acid sequence. In contrast to DmAK WT (wild type), the enzyme activity of the H227A mutant decreases by 18%. To identify the structure-function relationship of this H227A mutant enzyme, the crystal 3D X-ray structure has been determined and an unfolding assay using anilino-1-naphthalenesulfonic acid (ANS) fluorescence has been undertaken. The results revealed that when compared to the DmAK WT, the hydrogen bonding between H227 and A135 was broken in the H227A crystal structure. This suggests that H227 residue, closed to the arginine binding site, plays an important role in maintaining the structural stability and maximizing the enzyme activity through hydrogen bonding with the backbone oxygen of A135.


Assuntos
Arginina Quinase/química , Proteínas de Artrópodes/química , Daphnia/enzimologia , Animais , Arginina Quinase/genética , Arginina Quinase/metabolismo , Proteínas de Artrópodes/genética , Proteínas de Artrópodes/metabolismo , Cristalografia por Raios X , Daphnia/química , Daphnia/genética , Daphnia/metabolismo , Estabilidade Enzimática , Modelos Moleculares , Mutação Puntual , Conformação Proteica , Especificidade por Substrato
3.
Eur Radiol ; 31(9): 7184-7191, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33733688

RESUMO

OBJECTIVES: To assess interobserver agreement in Lung CT Screening Reporting and Data System (Lung-RADS) categorisation in subsolid nodule-enriched low-dose screening CTs. METHODS: A retrospective review of low-dose screening CT reports from 2013 to 2017 using keyword searches for subsolid nodules identified 54 baseline CT scans. With an additional 108 negative screening CT scans, a total of 162 CT scans were categorised according to the Lung-RADS by two fellowship-trained thoracic radiologists in consensus. We randomly selected 20, 20, 10, and 10 scans from categories 1/2, 3, 4A, and 4B CT scans, respectively, to ensure balanced category representation. Five radiologists classified the 60 CT scans into Lung-RADS categories. The frequencies of concordance and minor and major discordance were calculated, with major discordance defined as at least 6 months of management discrepancy. We used Cohen's κ statistics to analyse reader agreement. RESULTS: An average of 60.3% (181 of 300) of all cases and 45.0% (90 of 200) of positive screens were correctly categorised. The minor and major discordance rates were 12.3% and 27.3% overall and 18.5% and 36.5% in positive screens, respectively. The concordance rate was significantly higher among experienced thoracic radiologists. Overall, the interobserver agreement was moderate (mean κ, 0.45; 95% confidence interval: 0.40-0.51). The proportion of part-solid risk-dominant nodules was significantly higher in cases with low rates of accurate categorisation. CONCLUSION: This retrospective study observed variable accuracy and moderate interobserver agreement in radiologist categorisation of subsolid nodules in screening CTs. This inconsistency may affect management recommendations for lung cancer screening. KEY POINTS: • Diagnostic performance for Lung-RADS categorisation is variable among radiologists with fair to moderate interobserver agreement in subsolid nodule-enriched CT scans. • Experienced thoracic radiologists showed more accurate and consistent Lung-RADS categorisation than radiology residents. • The relative abundance of part-solid nodules was a potential factor related to increased disagreement in Lung-RADS categorisation.


Assuntos
Neoplasias Pulmonares , Detecção Precoce de Câncer , Humanos , Pulmão/diagnóstico por imagem , Neoplasias Pulmonares/diagnóstico por imagem , Variações Dependentes do Observador , Estudos Retrospectivos , Tomografia Computadorizada por Raios X
4.
Sensors (Basel) ; 20(8)2020 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-32316441

RESUMO

A vibration isolator embedded in precision equipment, such as a scanning electron microscope (SEM), wafer inspection equipment, and nanoimprint lithography equipment, play a critical role in achieving the maximum performance of the equipment during the fabrication of nano/micro-electro-mechanical systems. In this study, the factors that degrade the performance of SEM equipment with isolation devices are classified and discussed, and improvement measures are proposed from the viewpoints of the measured image patterns and vibrations in comparison with the relevant vibration criteria. In particular, this study quantifies the image patterns measured using SEMs, and the results are discussed along with the measured vibration. A guide for the selection of mounting equipment is presented by performing vibration analysis on the lower mount of the dual elastic mount configuration applied to the SEM, as well as the image patterns analyzed with that configuration. In addition, design modifications for the mount and its arrangement are suggested based on impact tests and numerical simulations.

5.
Nature ; 497(7447): 142-6, 2013 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-23604253

RESUMO

Arrestins interact with G-protein-coupled receptors (GPCRs) to block interaction with G proteins and initiate G-protein-independent signalling. Arrestins have a bi-lobed structure that is stabilized by a long carboxy-terminal tail (C-tail), and displacement of the C-tail by receptor-attached phosphates activates arrestins for binding active GPCRs. Structures of the inactive state of arrestin are available, but it is not known how C-tail displacement activates arrestin for receptor coupling. Here we present a 3.0 Å crystal structure of the bovine arrestin-1 splice variant p44, in which the activation step is mimicked by C-tail truncation. The structure of this pre-activated arrestin is profoundly different from the basal state and gives insight into the activation mechanism. p44 displays breakage of the central polar core and other interlobe hydrogen-bond networks, leading to a ∼21° rotation of the two lobes as compared to basal arrestin-1. Rearrangements in key receptor-binding loops in the central crest region include the finger loop, loop 139 (refs 8, 10, 11) and the sequence Asp 296-Asn 305 (or gate loop), here identified as controlling the polar core. We verified the role of these conformational alterations in arrestin activation and receptor binding by site-directed fluorescence spectroscopy. The data indicate a mechanism for arrestin activation in which C-tail displacement releases critical central-crest loops from restricted to extended receptor-interacting conformations. In parallel, increased flexibility between the two lobes facilitates a proper fitting of arrestin to the active receptor surface. Our results provide a snapshot of an arrestin ready to bind the active receptor, and give an insight into the role of naturally occurring truncated arrestins in the visual system.


Assuntos
Arrestinas/química , Arrestinas/metabolismo , Isoformas de Proteínas/química , Isoformas de Proteínas/metabolismo , Processamento Alternativo , Animais , Arrestinas/genética , Bovinos , Cristalografia por Raios X , Ligação de Hidrogênio , Modelos Moleculares , Peso Molecular , Conformação Proteica , Isoformas de Proteínas/genética , Rotação , Deleção de Sequência , Eletricidade Estática , beta-Arrestinas
6.
Molecules ; 24(23)2019 11 27.
Artigo em Inglês | MEDLINE | ID: mdl-31783554

RESUMO

Conventional fluorescent lamps that are used in tissue culture are costly light sources, exhibiting excessive wavelength emission-bandwidth that must be replaced by alternative, less costly, and much lower power-consuming energy sources. The use of Light-Emitting Diodes (LEDs) is the best option due to their potential role as elicitors of secondary metabolite production in many plant models. Gynura procumbens (G. procumbens) is widely used for treating various diseases. Here, leaf explants were cultivated in MS medium that was supplemented with 0.5 mg/L of naphthaleneacetic acid (NAA) and 2.0 mg/L of benzylaminopurine (BAP) for 30 days under white, blue, and red LEDs. Secondary metabolites were analyzed by High Performance Liquid Chromatography (HPLC) and Liquid Chromatography-Mass Spectrometry (LC-MS). Blue LEDs elicited the highest antioxidant activity, total flavonoid, and phenolic content. Furthermore, the content of cyanidin-monoglucosides significantly increased under blue light.


Assuntos
Antocianinas/metabolismo , Antioxidantes/química , Asteraceae/química , Luz , Antocianinas/análise , Antocianinas/química , Antioxidantes/análise , Antioxidantes/metabolismo , Asteraceae/crescimento & desenvolvimento , Asteraceae/metabolismo , Biomassa , Células Cultivadas , Cromatografia Líquida de Alta Pressão , Espectrometria de Massas , Fenóis/análise , Fenóis/metabolismo , Fotobiologia , Células Vegetais , Folhas de Planta/química , Folhas de Planta/crescimento & desenvolvimento , Folhas de Planta/metabolismo
7.
Nature ; 471(7340): 651-5, 2011 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-21389988

RESUMO

G-protein-coupled receptors (GPCRs) are seven transmembrane helix (TM) proteins that transduce signals into living cells by binding extracellular ligands and coupling to intracellular heterotrimeric G proteins (Gαßγ). The photoreceptor rhodopsin couples to transducin and bears its ligand 11-cis-retinal covalently bound via a protonated Schiff base to the opsin apoprotein. Absorption of a photon causes retinal cis/trans isomerization and generates the agonist all-trans-retinal in situ. After early photoproducts, the active G-protein-binding intermediate metarhodopsin II (Meta II) is formed, in which the retinal Schiff base is still intact but deprotonated. Dissociation of the proton from the Schiff base breaks a major constraint in the protein and enables further activating steps, including an outward tilt of TM6 and formation of a large cytoplasmic crevice for uptake of the interacting C terminus of the Gα subunit. Owing to Schiff base hydrolysis, Meta II is short-lived and notoriously difficult to crystallize. We therefore soaked opsin crystals with all-trans-retinal to form Meta II, presuming that the crystal's high concentration of opsin in an active conformation (Ops*) may facilitate all-trans-retinal uptake and Schiff base formation. Here we present the 3.0 Å and 2.85 Å crystal structures, respectively, of Meta II alone or in complex with an 11-amino-acid C-terminal fragment derived from Gα (GαCT2). GαCT2 binds in a large crevice at the cytoplasmic side, akin to the binding of a similar Gα-derived peptide to Ops* (ref. 7). In the Meta II structures, the electron density from the retinal ligand seamlessly continues into the Lys 296 side chain, reflecting proper formation of the Schiff base linkage. The retinal is in a relaxed conformation and almost undistorted compared with pure crystalline all-trans-retinal. By comparison with early photoproducts we propose how retinal translocation and rotation induce the gross conformational changes characteristic for Meta II. The structures can now serve as models for the large GPCR family.


Assuntos
Rodopsina/química , Rodopsina/metabolismo , Sítios de Ligação , Sequência Conservada , Cristalização , Cristalografia por Raios X , Subunidades alfa de Proteínas de Ligação ao GTP/química , Subunidades alfa de Proteínas de Ligação ao GTP/metabolismo , Ligantes , Modelos Moleculares , Opsinas/química , Fragmentos de Peptídeos/química , Fragmentos de Peptídeos/metabolismo , Conformação Proteica , Retinaldeído/química , Retinaldeído/metabolismo , Bases de Schiff/química , Eletricidade Estática
8.
Nature ; 455(7212): 497-502, 2008 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-18818650

RESUMO

Opsin, the ligand-free form of the G-protein-coupled receptor rhodopsin, at low pH adopts a conformationally distinct, active G-protein-binding state known as Ops*. A synthetic peptide derived from the main binding site of the heterotrimeric G protein-the carboxy terminus of the alpha-subunit (GalphaCT)-stabilizes Ops*. Here we present the 3.2 A crystal structure of the bovine Ops*-GalphaCT peptide complex. GalphaCT binds to a site in opsin that is opened by an outward tilt of transmembrane helix (TM) 6, a pairing of TM5 and TM6, and a restructured TM7-helix 8 kink. Contacts along the inner surface of TM5 and TM6 induce an alpha-helical conformation in GalphaCT with a C-terminal reverse turn. Main-chain carbonyl groups in the reverse turn constitute the centre of a hydrogen-bonded network, which links the two receptor regions containing the conserved E(D)RY and NPxxY(x)(5,6)F motifs. On the basis of the Ops*-GalphaCT structure and known conformational changes in Galpha, we discuss signal transfer from the receptor to the G protein nucleotide-binding site.


Assuntos
Subunidades alfa de Proteínas de Ligação ao GTP/química , Subunidades alfa de Proteínas de Ligação ao GTP/metabolismo , Opsinas de Bastonetes/química , Opsinas de Bastonetes/metabolismo , Motivos de Aminoácidos , Animais , Arginina/química , Arginina/metabolismo , Sítios de Ligação , Bovinos , Sequência Conservada , Cristalização , Cristalografia por Raios X , Modelos Biológicos , Modelos Moleculares , Conformação Proteica , Regeneração , Retinaldeído/química , Retinaldeído/metabolismo , Rodopsina/química , Transdução de Sinais
9.
J Ginseng Res ; 48(1): 98-102, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38223827

RESUMO

Background: Ginseng (Panax ginseng Meyer) is a perennial plant belonging to the Araliaceae family that is known to have various beneficial effects including improving memory loss and spatial cognitive ability, and anti-cancer and anti-diabetes activity. Its functional benefits also include improving liver function, regulating blood pressure, stress, and providing antioxidant activity. Usually, various agrochemicals are used in cultivating ginseng preventing from many diseases. Methods: FCGP (field cultivated ginseng in pot) was implemented by imitating MCWG (mountain cultivated wild ginseng). Pesticide analysis of pot cultivation was carried out and the contents of bioactive components such as ginsenoside were also analyzed. Results: FCGP ginsenoside content was higher than that of FCG (field cultivated ginseng) and MCWG. FCGP has been shown to have a relatively high antioxidant effect compared with cultivated ginseng. Conclusion: It was confirmed that ginseng can be grown for 6 years without resorting to use of pesticides. In addition, it was confirmed that effective accumulation of physiologically active ingredients such as ginsenoside is possible. Our result represents FCGP is a novel method of pesticide-free ginseng cultivation.

10.
J Anim Sci Technol ; 65(3): 535-549, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-37332281

RESUMO

This study was to investigate the effects of different phytogenic feed additives (PFA) dosage levels in growing- finishing pigs stressed by high stocking density. A total of 72 mix sexed 12 weeks growing pigs ([Landrace × Yorkshire] × Duroc) with initial body weight (BW) of 49.28 ± 4.58 kg were used for 8 weeks. There were 3 replicate pens in each treatment group, with 3 pigs per pen. The dietary treatment groups consisted of basal diets in animal welfare density (negative control [NC]), basal diet in high stocking density (positive control [PC]), PC + 0.04% essential oil (ES1), PC + 0.08% essential oil (ES2), PC + 0.10% bitter citrus extract & essential oil (CES1), PC + 0.20% bitter citrus extract & essential oil (CES2), PC + 0.05% grape pomace extract (GP1), PC + 0.10% grape pomace extract (GP2). The reduction of space allowance decreased (p < 0.05) average daily gain, feed efficiency, and digestibility of dry matter, crude protein, and gross energy. Also, the fecal score of PC groups increased (p < 0.05) compared with other groups. Basic behaviors (feed intake, standing, lying) were inactive (p < 0.05) and singularity behavior (biting) was increased (p < 0.10) under high stocking density. There was no difference in blood profile. However, the supplementation of PFA alleviated the negative effects such as reduced growth performance, nutrient digestibility, and some increasing stress indicators in th blood (cortisol) and animal behavior (biting). In conclusion, the negative effect of high stocking density was most effectively mitigated by the normal dosage of the mixture of bitter citrus extract and essential oil additive (CES1).

11.
J Anim Sci Technol ; 64(6): 1063-1076, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36812026

RESUMO

Two experiments were conducted to determine the effect of Hermetia illucens larvae (HIL) as protein and protease on growth performance, blood profiles, fecal microflora, and gas emission in growing pig. In experiment 1, the seventy-two crossbred growing pigs ([Landrace × Yorkshire] × Duroc) with an initial body weight (BW) of 27.98 ± 2.95 kg were randomly allotted to one of four dietary treatments (3 pigs per pen and 6 replicates pen per treatments). The experimental design was a 2 × 2 factorial arrangement of treatments evaluating two diets (Poultry offal diets and HIL diets) without or with supplementing protease. The poultry offal in basal diet has been replaced by HIL. In experiment 2, the four crossbred growing pigs ([Landrace × Yorkshire] × Duroc) with an initial BW of 28.2 ± 0.1 kg were individually accepted in stainless steel metabolism cages. The dietary treatments included: 1) PO- (PO-; poultry offal diet), 2) PO+ (PO- + 0.05% protease), 3) HIL- (3% PO of PO- diet was replacement 3% HIL), 4) HIL+ (HIL- + 0.05% protease). In experiment 1, From weeks 0 to 2, average daily gain (ADG) and feed efficiency (G:F) were significantly increased in the PO diet group compared with the HIL group. From weeks 2 to 4, ADG and G:F were higher for protease group than for non-protease group. At weeks 2 and 4, the PO diet group had lower blood urea nitrogen (BUN) levels than HIL diet group. In experiment 2, crude protein (CP) and nitrogen (N) retention were decreased by HIL diet at weeks 2 and 4. The fecal microflora and gas emission were not affected by HIL and protease. The HIL diet showed lower CP digestibility than PO diet and total essential amino acids digestibility tended to higher in PO diet than HIL diet. In summary, the present study revealed that replacement of the PO protein with the HIL protein and the additive of protease in growing pig diets during the overall experimental period had no negative effect.

12.
J Anim Sci Biotechnol ; 13(1): 100, 2022 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-36100948

RESUMO

BACKGROUND: Two experiments were conducted to establish an optimal NE challenge model and evaluate the efficacy of stimbiotic (STB) supplementation in necrotic enteritis (NE) challenged broilers. In Exp. 1, a total of 120 Arbor Acres (AA) broilers (45.0 ± 0.21 g) were randomly assigned to 6 treatments in a 3 × 2 factorial arrangement. Vaccine treatments included non-challenge (0), × 10 the recommended dose (× 10) or × 20 the recommended dose (× 20) by the manufacturer. Clostridium perfringens (CP) treatments were non-challenge (No) or 3 mL of 2.2 × 107 CFU CP challenge (Yes). In Exp. 2, a total of 72 AA broilers (40.17 ± 0.27 g) were randomly assigned to 6 treatments in a 3 × 2 factorial arrangement. Dietary treatments included non-additive (CON), 100 mg/kg STB (STB) and 100 mg/kg STB on top of a typical commercial blend including an essential oil, probiotics, and enzyme (CB). Challenge treatments included non-NE challenge (No) and NE challenge (Yes) as established in Exp. 1. RESULTS: In Exp. 1, CP and vaccine challenge decreased (P < 0.05) body weight (BW), body weight gain (BWG) and feed intake (FI), and increased (P < 0.05) the number of broilers with diarrhea and intestinal lesions. The oral administration of × 20 recommended dose of vaccines coupled with 3 mL of 2.2 × 107 CFU CP resulted in (P < 0.01) a significantly increased incidence of wet litter and intestinal lesions. Thus, this treatment was chosen as the challenge model for the successful inducement of NE in Exp. 2. In Exp. 2, the NE challenge negatively affected (P < 0.01) growth performance, ileal morphology, immunoglobulin contents in blood, caecal microbiota in the caecum, footpad dermatitis, intestinal lesion scores, tumour necrosis factor (TNF-α) and endotoxin in the serum compared with the non-NE challenged birds. The supplementation of STB and CB in diets enhanced (P < 0.05) growth performance, intestinal microbiota, and blood profiles by stimulating ileal morphology (VH and VH:CD) and propionate production in the cecum, and there were no differences in measured variables between STB and CB supplemented birds. CONCLUSION: Overall, these results indicate that STB supplementation was able to reduce the inflammatory response and improve the performance of NE challenged birds, and the supplementation of STB alone was as effective as a typical commercial blend containing a number of other additives.

13.
J Anim Sci Technol ; 64(2): 291-301, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35530405

RESUMO

The objective of this study was to evaluate the effects of different mixing ratios of Bacillus licheniformis and Bacillus subtilis in diets on nutrient digestibility, fecal microflora, and odor gas emissions of growing pigs. A total of four crossbred ([Landrace × Yorkshire] × Duroc) barrows with average body weight (BW) of 41.2 ± 0.7 kg were randomly allotted four diets over four periods in a 4 × 4 Latin square design. Treatments were as follows: Control (CON, basal diet), CON + 0.2% probiotic complex (L4S6, B. licheniformis and B. subtilis at a 4:6 ratio), CON + 0.2% probiotic complex (L5S5, B. licheniformis and B. subtilis at a 5:5 ratio), CON + 0.2% probiotic complex (L6S4, B. licheniformis and B. subtilis at a 6:4 ratio). Dietary probiotic supplementation showed higher crude protein (CP) digestibility values and lower Escherichia coli counts in fecal samples than the CON group (p < 0.05). There was no significant difference in NH3 or H2S emission until day 3. The positive effect of H2S and NH3 emissions was detected earlier with the L4S6 and L5S5 compared to the L6S4, which had a lower ratio of B. subtilis. Both the L4S6 and L5S5 probiotic complexes significantly decreased the fecal H2S and NH3 emission in days 4 and 6 (p < 0.05). On day 7, all probiotic complexes decreased (p < 0.05) H2S and NH3 emissions than the CON group. Our results agreed that the dietary supplementation of Bacillus licheniformis and Bacillus subtilis complexes in growing pigs can significantly improve CP digestibility and reduce fecal E. coli counts, NH3 and H2S emissions. Notably, the higher mixing ratio of Bacillus subtilis in probiotic supplementation is more effective in reducing the odor of manure.

14.
J Anim Sci Technol ; 64(1): 23-37, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-35174340

RESUMO

Thirty-six weaned piglets with an initial body weight (BW) of 8.43 ± 0.40 kg (28 days of age, ([Landrace × Yorkshire] × Duroc) were randomly assigned to 6 treatments for a 2-week feeding trial to determine the effects of different inorganic zinc (IZ), organic zinc (OZ) or combination of low crude protein diet (LP) and Mixed feed additive (MFA) on diarrhea score, nutrient digestibility, zinc utilization, blood profiles, organ weight, and fecal microflora in weaned piglet diet. The pigs were individually placed in 45 × 55 × 45 cm stainless steel metabolism cages in an environmentally controlled room (30 ± 1°C). The dietary treatments included a negative control (NC), positive control (PC; zinc oxide, 1,000 mg/kg), T1 (IZ : OZ, 850 : 150), T2 (IZ : OZ 700 : 300), T3 (IZ : OZ, 500 : 500), and T4 (LP + MFA [0.1% Essential oils + 0.08% Protease + 0.02% Xylanase]). The daily feed allowance was adjusted to 2.7 times the maintenance requirement for digestible energy (2.7 × 110 kcal of DE/kg BW0.75). This allowance was divided into two equal parts, and the piglets were fed at 08 : 30 and 17 : 30 each day. Water was provided ad libitum through a drinking nipple. The diarrhea score was significantly increased (p < 0.05) in NC treatment compared with other treatments. The apparent total tract digestibility (ATTD) of dry matter (DM), nitrogen (N), and gross energy (GE) was significantly increased (p < 0.05) in the T2 treatment compared with the PC and NC treatments in week 1. In week 2, the ATTD of DM, N, and GE was significantly decreased (p < 0.05) in the NC treatment compared with other treatments. The T3 treatment had significantly higher (p < 0.05) ATTD and apparent ileal digestibility of zinc than the PC and T1 treatments. The Escherichia coli count in feces was significantly decreased in the T4 treatment compared with the NC and T2 treatments. The Lactobacillus count in feces was significantly increased in the T4 and T1 treatment compared with the T2 and T3 treatments. In conclusion, IZ : OZ 500 : 500 levels could improve nutrient digestibility and zinc utilization in weaned piglets, Moreover, MFA in LP diets could be used as a zinc alternative.

15.
Structure ; 30(2): 263-277.e5, 2022 02 03.
Artigo em Inglês | MEDLINE | ID: mdl-34678158

RESUMO

Visual arrestin (Arr1) terminates rhodopsin signaling by blocking its interaction with transducin. To do this, Arr1 translocates from the inner to the outer segment of photoreceptors upon light stimulation. Mounting evidence indicates that inositol phosphates (InsPs) affect Arr1 activity, but the Arr1-InsP molecular interaction remains poorly defined. We report the structure of bovine Arr1 in a ligand-free state featuring a near-complete model of the previously unresolved C-tail, which plays a crucial role in regulating Arr1 activity. InsPs bind to the N-domain basic patch thus displacing the C-tail, suggesting that they prime Arr1 for interaction with rhodopsin and help direct Arr1 translocation. These structures exhibit intact polar cores, suggesting that C-tail removal by InsP binding is insufficient to activate Arr1. These results show how Arr1 activity can be controlled by endogenous InsPs in molecular detail.


Assuntos
Arrestina/química , Arrestina/metabolismo , Fosfatos de Inositol/metabolismo , Rodopsina/metabolismo , Animais , Bovinos , Cristalografia por Raios X , Camundongos , Modelos Moleculares , Conformação Proteica , Domínios Proteicos , Análise de Sequência de RNA , Análise de Célula Única
16.
J Anim Sci Biotechnol ; 13(1): 107, 2022 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-36050784

RESUMO

BACKGROUND: This study was conducted to investigate the effects of each phytogenic feed additive (PFA; PFA1, bitter citrus extract; PFA2, a microencapsulated blend of thymol and carvacrol; PFA3, a mixture of bitter citrus extract, thymol, and carvacrol; PFA4, a premixture of grape seed, grape marc extract, green tea, and hops; PFA5, fenugreek seed powder) on the growth performance, nutrient digestibility, intestinal morphology, and immune response in weaned pigs infected with Escherichia coli (E. coli). RESULTS: A total of 63 4-week-old weaned pigs were placed in individual metabolic cages and assigned to seven treatment groups. The seven treatments were as follows: 1) NC; basal diet without E. coli challenge, 2) PC; basal diet with E. coli challenge, 3) T1; PC + 0.04% PFA1, 4) T2; PC + 0.01% PFA2, 5) T3; PC + 0.10% PFA3, 6) T4; PC + 0.04% PFA4, 7) T5; PC + 0.10% PFA5. The experiments lasted in 21 d, including 7 d before and 14 d after the first E. coli challenge. In the E. coli challenge treatments, all pigs were orally inoculated by dividing a total of 10 mL of E. coli F18 for 3 consecutive days. The PFA-added groups significantly increased (P < 0.05) average daily gain and feed efficiency and decreased (P < 0.05) the fecal score at d 0 to 14 post-inoculation (PI). Tumor necrosis factor α was significantly lower (P < 0.05) in the PFA-added groups except for T1 in d 14 PI compared to the PC treatment. The T3 had a higher (P < 0.05) immunoglobulin G and immunoglobulin A concentration compared to the PC treatment at d 7 PI. Also, T3 showed significantly higher (P < 0.05) villus height:crypt depth and claudin 1 expression in ileal mucosa, and significantly down-regulated (P < 0.05) the expression of calprotectin compared to the PC treatment. CONCLUSIONS: Supplementation of PFA in weaned pigs challenged with E. coli alleviated the negative effects of E. coli and improved growth performance. Among them, the mixed additive of bitter citrus extract, thymol, and carvacrol showed the most effective results, improving immune response, intestinal morphology, and expression of tight junctions.

17.
Artigo em Inglês | MEDLINE | ID: mdl-33613686

RESUMO

As a known steroid hormone, cortisol is involved in gluconeogenesis. Uninterrupted cortisol secretion has fatal effects, both physically and psychologically, because cortisol counteracts the immune response. Moxibustion (Mox) treatment is a traditional technique used in East Asia, which therapeutically transfers heat to certain points on the body surface. In the present study, the effect of Mox treatment on stress hormone secretion was investigated using a mouse model of starvation, in which Mox was applied on the Zhongwan acupoint (CV12). First, high cortisol levels induced by starvation were dose-dependently reduced by Mox treatment. In addition, the stress-induced decline in lymphoid progenitor cell production accompanied by altered cellularity in the thymus, bone marrow, and spleen was also significantly recovered by Mox treatment. Taken together, these findings indicated that Mox treatment reduces stress hormone secretion, which may rescue stress-induced lymphopoiesis impairment. These observations also suggested that enhanced resistance to stress may be one of the mechanisms underlying the immunomodulatory effects of Mox treatment.

18.
Sci Rep ; 11(1): 20933, 2021 Oct 22.
Artigo em Inglês | MEDLINE | ID: mdl-34686722

RESUMO

Scanning electron microscopy (SEM) is a high-resolution imaging technique with subnanometer spatial resolution that is widely used in materials science, basic science, and nanofabrication. However, conducting SEM is rather complex due to the nature of using an electron beam and the many parameters that must be adjusted to acquire high-quality images. Only trained operators can use SEM equipment properly, meaning that the use of SEM is restricted. To broaden the usability of SEM, we propose an autofocus method for a SEM system based on a dual deep learning network, which consists of an autofocusing-evaluation network (AENet) and an autofocusing-control network (ACNet). The AENet was designed to evaluate the quality of given images, with scores ranging from 0 to 9 regardless of the magnification. The ACNet can delicately control the focus of SEM online based on the AENet's outputs for any lateral sample position and magnification. The results of these dual networks showed successful autofocus performance on three trained samples. Moreover, the robustness of the proposed method was demonstrated by autofocusing on unseen samples. We expect that our autofocusing system will not only contribute to expanding the versatility of SEM but will also be applicable to various microscopes.

19.
J Anim Sci Technol ; 63(3): 491-500, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-34189499

RESUMO

The objective of this study was to evaluate the effects of low protein diets added with protease on growth performance, nutrient digestibility, and blood profiles of weaned piglets and growing-finishing pigs. A total of 96 weaned pigs ([Yorkshire × Landrace] × Duroc) with average body weight (BW) of 6.99 ± 0.21 kg were used in a 20-week experiment. The dietary treatments were arranged in a 2 × 3 factorial design. Treatments were as follows: In phase 1 (1-2 weeks), two protein levels as high protein (HP; 19.0%), low protein (LP; 17.0%), and three protease (PT) levels (PT0, 0%; PT1, 0.3%; and PT2, 0.5%); in phase 2 (3-4 weeks), protein levels (HP, 18.05%; LP, 16.15%) and protease levels (0%, 0.3%, and 0.5%); in phase 3 (5-12 weeks), protein levels (HP, 17.1%; LP, 15.3%) and protease level (0%, 0.15%, and 0.3%); in phase 4 (13-20 weeks), protein levels (HP, 16.15%; LP, 14.45%) and protease level (0%, 0.15%, and 0.3%). At 4 weeks and 20 weeks after treatment, BW was higher (p < 0.050) in the PT2 group than PT0 group. From weeks 0 to 4, average daily gain (ADG) and feed efficiency (G/F) were higher (p = 0.006 and p = 0.014; p = 0.014 and p = 0.044, respectively) in the PT2 group than PT0 and PT1 groups. From weeks 16 to 20, ADG and G/F were higher (p < 0.001 and p = 0.009; p = 0.004 and p = 0.033, respectively) in the PT2 group than PT0 and PT1 groups. Crude protein (CP) digestibility was higher (p = 0.013, p = 0.014, and p = 0.035, respectively) in the low protein (LP) group than high protein (HP) group at weeks 4, 12, and 20. At weeks 4 and 20, the LP diet group had lower (p < 0.001 and p = 0.001, respectively) blood urea nitrogen (BUN) levels than the HP diet group. Therefore, a low CP diet added with protease could increase growth performance and CP digestibility of weaned piglets and growing-finishing pigs.

20.
J Anim Sci Technol ; 63(1): 104-113, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33987588

RESUMO

This study was conducted to investigate the efficiency of a microencapsulated mixture of organic acids (MOA) with low protein in piglet feed on growth performance, diarrhea score, nutrient digestibility, fecal microbial counts, and blood profiles in weaning pigs. A total of 80 pigs [(Landrace × Yorkshire) × Duroc; 6.8 ± 0.48 kg] were randomly assigned to four dietary treatment groups: high protein (HP); low protein (LP); MOA1, LP + 0.2% MOA; and MOA2, LP + 0.3% MOA. The MOA2 group had higher average daily weight gains (during days 0-14 and days 0-28), diarrhea score (during days 0-14, during days 14-28 and days 0-28) and greater digestibility of dry matter (days 14 and 28) compared to the LP group (p < 0.05). However, there were no significant differences (p > 0.05) between the pigs fed diets with the MOA1 and MOA2 in blood profiles and fecal microflora. In conclusion, this study indicates that piglets fed 0.3% MOA in low protein diets maintained similar growth performance and nutrient digestibility, but alleviated the incidence of diarrhea compared to piglets fed high protein diets.

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