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1.
J Am Chem Soc ; 146(13): 9181-9190, 2024 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-38528433

RESUMO

Many unique adsorption properties of metal-organic frameworks (MOFs) have been revealed by diffraction crystallography, visualizing their vacant and guest-loaded crystal structures at the molecular scale. However, it has been challenging to see the spatial distribution of the adsorption behaviors throughout a single MOF particle in a transient equilibrium state. Here, we report three-dimensional (3D) visualization of molecular adsorption behaviors in a single crystalline particle of a MOF by in situ X-ray absorption fine structure spectroscopy combined with computed tomography for the first time. The 3D maps of water-coordinated Co sites in a 100 µm-scale MOF-74-Co crystal were obtained with 1 µm spatial resolution under several water vapor pressures. Through the visualization of the water vapor adsorption process, 3D spectroimaging revealed the mechanism and spatial heterogeneity of guest adsorption inside a single particle of a crystalline MOF.

2.
Protein Expr Purif ; 217: 106444, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38365166

RESUMO

The matrix of the stationary phase is a crucial element in affinity chromatography for protein purification. Various materials, including polymer or magnetic materials, have been employed as the matrix in the purification of His-tagged protein. Here, for the first time, we utilized a combination of melanin and alginate, both natural polymer materials, to synthesize Ni-melanin/alginate (Ni-M/A) beads for His-tagged protein purification. We investigated the binding of His-tagged Mpro on the Ni-M/A beads, referred to as Ni-M/A-Mpro, and assessed the elution efficiency of Mpro from the beads. Our examination involved FTIR, EDS, XRD, SDS-PAGE, and Western blotting methods. FTIR spectra revealed notable changes in the stretching patterns and intensities of hydroxyl, amine, carbonyl, imine and amide chemical groups, when Mpro protein was present in the Ni-M/A sample. XRD spectra demonstrated the occurrence of two Nickel peaks at 35-40 deg and 40-45 deg in Ni-M/A, but only one nickel peak at 35-40 deg in Ni-M/A-Mpro, indicating the binding of Mpro on the Nickel ions. EDS analysis reported a decrease in the concentration of Nickel on the surface of Ni-M/A from 16% to 7% when Mpro protein was loaded into the stationary phase. Importantly, our data indicated that the purity of the His-tagged protein Mpro after purification reached 97% after just one-step purification using the Ni-M/A stationary phase. Moreover, the binding capacity of Ni-M/A for Mpro was approximately 5.2 mg/g with recovery efficiency of 40%. Our results suggested Ni-M/A as a highly potential solid phase for affinity chromatography in the purification of His-tagged protein.


Assuntos
Melaninas , Níquel , Níquel/química , Histidina/química , Cromatografia de Afinidade/métodos , Íons , Polímeros , Alginatos
3.
Molecules ; 29(10)2024 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-38792114

RESUMO

Flavonoids and stilbenoids, crucial secondary metabolites abundant in plants and fungi, display diverse biological and pharmaceutical activities, including potent antioxidant, anti-inflammatory, and antimicrobial effects. However, conventional production methods, such as chemical synthesis and plant extraction, face challenges in sustainability and yield. Hence, there is a notable shift towards biological production using microorganisms like Escherichia coli and yeast. Yet, the drawbacks of using E. coli and yeast as hosts for these compounds persist. For instance, yeast's complex glycosylation profile can lead to intricate protein production scenarios, including hyperglycosylation issues. Consequently, Corynebacterium glutamicum emerges as a promising alternative, given its adaptability and recent advances in metabolic engineering. Although extensively used in biotechnological applications, the potential production of flavonoid and stilbenoid in engineered C. glutamicum remains largely untapped compared to E. coli. This review explores the potential of metabolic engineering in C. glutamicum for biosynthesis, highlighting its versatility as a cell factory and assessing optimization strategies for these pathways. Additionally, various metabolic engineering methods, including genomic editing and biosensors, and cofactor regeneration are evaluated, with a focus on C. glutamicum. Through comprehensive discussion, the review offers insights into future perspectives in production, aiding researchers and industry professionals in the field.


Assuntos
Corynebacterium glutamicum , Flavonoides , Engenharia Metabólica , Estilbenos , Corynebacterium glutamicum/metabolismo , Corynebacterium glutamicum/genética , Engenharia Metabólica/métodos , Flavonoides/biossíntese , Flavonoides/metabolismo , Estilbenos/metabolismo
4.
Sensors (Basel) ; 23(21)2023 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-37960447

RESUMO

Artificial intelligence (AI) radar technology offers several advantages over other technologies, including low cost, privacy assurance, high accuracy, and environmental resilience. One challenge faced by AI radar technology is the high cost of equipment and the lack of radar datasets for deep-learning model training. Moreover, conventional radar signal processing methods have the obstacles of poor resolution or complex computation. Therefore, this paper discusses an innovative approach in the integration of radar technology and machine learning for effective surveillance systems that can surpass the aforementioned limitations. This approach is detailed into three steps: signal acquisition, signal processing, and feature-based classification. A hardware prototype of the signal acquisition circuitry was designed for a Continuous Wave (CW) K-24 GHz frequency band radar sensor. The collected radar motion data was categorized into non-human motion, human walking, and human walking without arm swing. Three signal processing techniques, namely short-time Fourier transform (STFT), mel spectrogram, and mel frequency cepstral coefficients (MFCCs), were employed. The latter two are typically used for audio processing, but in this study, they were proposed to obtain micro-Doppler spectrograms for all motion data. The obtained micro-Doppler spectrograms were then fed to a simplified 2D convolutional neural networks (CNNs) architecture for feature extraction and classification. Additionally, artificial neural networks (ANNs) and 1D CNN models were implemented for comparative analysis on various aspects. The experimental results demonstrated that the 2D CNN model trained on the MFCC feature outperformed the other two methods. The accuracy rate of the object classification models trained on micro-Doppler features was 97.93%, indicating the effectiveness of the proposed approach.


Assuntos
Inteligência Artificial , Radar , Humanos , Processamento de Sinais Assistido por Computador , Caminhada , Análise de Fourier
5.
J Asian Nat Prod Res ; 25(10): 1021-1028, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37200202

RESUMO

One novel chromanone acid derivative, namely inocalophylline C (1), together with one known compound calophyllolide (2), were isolated from the methanolic extract of nut oil resin of Calophyllum inophyllum L., a medicinal plant widely distributed in Vietnam. The isolated compound structures were elucidated by spectroscopic methods and the absolute configuration of 1 was established by the single-crystal X-ray crystallography as ethyl (R) 3-((2 R,3R,6R)-4-hydroxy-2,3-dimethyl-6-((R)-5-methyl-2-(prop-1-en-2-yl)hex-4-en-1-yl)-6-(3-methylbut-2-en-1-yl)-5,7-dioxo-3,5,6,7-tetrahydro-2H-chromen-8-yl)-3-phenylpropanoate.


Assuntos
Calophyllum , Nozes , Calophyllum/química , Extratos Vegetais/química , Metanol , Vietnã
6.
BMC Health Serv Res ; 21(1): 1051, 2021 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-34610841

RESUMO

BACKGROUND: Many tuberculosis (TB) patients incur catastrophic costs. Active case finding (ACF) may have socio-protective properties that could contribute to the WHO End TB Strategy target of zero TB-affected families suffering catastrophic costs, but available evidence remains limited. This study measured catastrophic cost incurrence and socioeconomic impact of an episode of TB and compared those socioeconomic burdens in patients detected by ACF versus passive case finding (PCF). METHODS: This cross-sectional study fielded a longitudinal adaptation of the WHO TB patient cost survey alongside an ACF intervention from March 2018 to March 2019. The study was conducted in six intervention (ACF) districts and six comparison (PCF) districts of Ho Chi Minh City, Viet Nam. Fifty-two TB patients detected through ACF and 46 TB patients in the PCF cohort were surveyed within two weeks of treatment initiation, at the end of the intensive phase of treatment, and after treatment concluded. The survey measured income, direct and indirect costs, and socioeconomic impact based on which we calculated catastrophic cost as the primary outcome. Local currency was converted into US$ using the average exchange rates reported by OANDA for the study period (VND1 = US$0.0000436, 2018-2019). We fitted logistic regressions for comparisons between the ACF and PCF cohorts as the primary exposures and used generalized estimating equations to adjust for autocorrelation. RESULTS: ACF patients were poorer than PCF patients (multidimensional poverty ratio: 16 % vs. 7 %; p = 0.033), but incurred lower median pre-treatment costs (US$18 vs. US$80; p < 0.001) and lower median total costs (US$279 vs. US$894; p < 0.001). Fewer ACF patients incurred catastrophic costs (15 % vs. 30 %) and had lower odds of catastrophic cost (aOR = 0.17; 95 % CI: [0.05, 0.67]; p = 0.011), especially during the intensive phase (OR = 0.32; 95 % CI: [0.12, 0.90]; p = 0.030). ACF patient experienced less social exclusion (OR = 0.41; 95 % CI: [0.18, 0.91]; p = 0.030), but more often resorted to financial coping mechanisms (OR = 5.12; 95 % CI: [1.73, 15.14]; p = 0.003). CONCLUSIONS: ACF can be effective in reaching vulnerable populations and mitigating the socioeconomic burden of TB, and can contribute to achieving the WHO End TB Strategy goals. Nevertheless, as TB remains a catastrophic life event, social protection efforts must extend beyond ACF.


Assuntos
Tuberculose , Estudos Transversais , Custos de Cuidados de Saúde , Humanos , Renda , Vietnã/epidemiologia
7.
BMC Public Health ; 20(1): 934, 2020 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-32539700

RESUMO

BACKGROUND: To achieve the WHO End TB Strategy targets, it is necessary to detect and treat more people with active TB early. Scale-up of active case finding (ACF) may be one strategy to achieve that goal. Given human resource constraints in the health systems of most high TB burden countries, volunteer community health workers (CHW) have been widely used to economically scale up TB ACF. However, more evidence is needed on the most cost-effective compensation models for these CHWs and their potential impact on case finding to inform optimal scale-up policies. METHODS: We conducted a two-year, controlled intervention study in 12 districts of Ho Chi Minh City, Viet Nam. We engaged CHWs as salaried employees (3 districts) or incentivized volunteers (3 districts) to conduct ACF among contacts of people with TB and urban priority groups. Eligible persons were asked to attend health services for radiographic screening and rapid molecular diagnosis or smear microscopy. Individuals diagnosed with TB were linked to appropriate care. Six districts providing routine NTP care served as control area. We evaluated additional cases notified and conducted comparative interrupted time series (ITS) analyses to assess the impact of ACF by human resource model on TB case notifications. RESULTS: We verbally screened 321,020 persons in the community, of whom 70,439 were eligible for testing and 1138 of them started TB treatment. ACF activities resulted in a + 15.9% [95% CI: + 15.0%, + 16.7%] rise in All Forms TB notifications in the intervention areas compared to control areas. The ITS analyses detected significant positive post-intervention trend differences in All Forms TB notification rates between the intervention and control areas (p = 0.001), as well as between the employee and volunteer human resource models (p = 0.021). CONCLUSIONS: Both salaried and volunteer CHW human resource models demonstrated additionality in case notifications compared to routine case finding by the government TB program. The salaried employee CHW model achieved a greater impact on notifications and should be prioritized for scale-up, given sufficient resources.


Assuntos
Agentes Comunitários de Saúde/estatística & dados numéricos , Análise Custo-Benefício/estatística & dados numéricos , Programas de Rastreamento/métodos , Programas de Rastreamento/estatística & dados numéricos , Tuberculose/diagnóstico , Recursos Humanos/estatística & dados numéricos , Adulto , Idoso , Idoso de 80 Anos ou mais , Cidades/estatística & dados numéricos , Feminino , Humanos , Análise de Séries Temporais Interrompida , Masculino , Pessoa de Meia-Idade , Vietnã
8.
Sensors (Basel) ; 20(7)2020 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-32268501

RESUMO

Water clarity is the most common indicator of water quality. The purpose of the study was to develop an instrument which can automatically measure water clarity in place of manual measurement by Secchi disk. The instrument is suspended by buoys at the water surface and uses solar energy to measure the light intensity of LED bulbs after passing through a water column; the result is then converted to Secchi depth by using a regression function. Measurement data are stored in a cloud server so that mobile users can access via an Internet connection. Three experiments were conducted to examine the instrument performance: (i) to ensure light intensity of the LED bulbs is strong enough to pass through the water column; (ii) to determine the regression relationship between the measured light intensity of the instrument and Secchi depth; and (iii) to evaluate the coefficient of variation (CV) of the measured water clarity when using our instrument and a conventional Secchi disk. Experiment results show that the measured values of light intensity are stable with the average CV = 5.25%. Moreover, although there are slight differences between the Secchi depth measured by our instrument and those measured by Secchi disk, the measurements by our instrument can efficiently replace the measurements by conventional Secchi disk, which can be affected by weather conditions as well as by human subjectivity.

9.
Mol Biol Evol ; 35(1): 247-251, 2018 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-29029186

RESUMO

Identifying recombinant sequences in an era of large genomic databases is challenging as it requires an efficient algorithm to identify candidate recombinants and parents, as well as appropriate statistical methods to correct for the large number of comparisons performed. In 2007, a computation was introduced for an exact nonparametric mosaicism statistic that gave high-precision P values for putative recombinants. This exact computation meant that multiple-comparisons corrected P values also had high precision, which is crucial when performing millions or billions of tests in large databases. Here, we introduce an improvement to the algorithmic complexity of this computation from O(mn3) to O(mn2), where m and n are the numbers of recombination-informative sites in the candidate recombinant. This new computation allows for recombination analysis to be performed in alignments with thousands of polymorphic sites. Benchmark runs are presented on viral genome sequence alignments, new features are introduced, and applications outside recombination analysis are discussed.


Assuntos
Rearranjo Gênico/genética , Recombinação Genética/genética , Análise de Sequência de DNA/métodos , Algoritmos , Filogenia , Alinhamento de Sequência/métodos , Análise de Sequência de DNA/estatística & dados numéricos , Software
10.
Biochem Biophys Res Commun ; 519(4): 880-886, 2019 11 19.
Artigo em Inglês | MEDLINE | ID: mdl-31561853

RESUMO

RhoA is a key player in actin cytoskeleton reorganization and exerts most of its effect through the RhoA-ROCKs signaling pathway. Although recent studies have stressed the roles of ROCKs as regulators of glucose metabolism, little is known of the roles played by RhoA, the upstream regulators of ROCKs and other isotypes of Rho small-GTPases. This study was undertaken to determine whether Rho isotypes modulate glucose transport and insulin signaling in insulin-sensitive cell models, that is, 3T3-L1 adipocytes and L6 myoblasts. Glucose uptake assays showed that RhoA knockdown using siRNA reduced insulin-stimulated glucose transport in both cell types, whereas knockdown of RhoB or RhoC did not. Furthermore, RhoA overexpression increased insulin-stimulated glucose transport. Interestingly, the insulin-stimulated PI3K-Akt signaling pathway was unaffected under RhoA-depleted or -overexpressed conditions, which suggested RhoA might regulate glucose transport via an Akt-independent pathway. Interestingly, an immunoblot assay of signaling molecules related to actin-myosin cytoskeletal remodeling showed that unlike RhoA or RhoC, RhoA regulated ERM phosphorylation. Our results suggest that RhoA, but not RhoB or RhoC, mediates glucose transport by regulating the vesicle trafficking machinery in an Akt-independent manner.


Assuntos
Adipócitos/metabolismo , Glucose/metabolismo , Mioblastos/metabolismo , Proteína rhoA de Ligação ao GTP/metabolismo , Células 3T3-L1 , Adipócitos/citologia , Animais , Transporte Biológico/efeitos dos fármacos , Linhagem Celular , Hipoglicemiantes/farmacologia , Insulina/farmacologia , Camundongos , Mioblastos/citologia , Proteínas Proto-Oncogênicas c-akt/metabolismo , Interferência de RNA , Ratos , Transdução de Sinais/efeitos dos fármacos , Proteína rhoA de Ligação ao GTP/genética
11.
Phys Rev Lett ; 122(19): 192501, 2019 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-31144924

RESUMO

We present a precision analysis of the ^{136}Xe two-neutrino ßß electron spectrum above 0.8 MeV, based on high-statistics data obtained with the KamLAND-Zen experiment. An improved formalism for the two-neutrino ßß rate allows us to measure the ratio of the leading and subleading 2νßß nuclear matrix elements (NMEs), ξ_{31}^{2ν}=-0.26_{-0.25}^{+0.31}. Theoretical predictions from the nuclear shell model and the majority of the quasiparticle random-phase approximation (QRPA) calculations are consistent with the experimental limit. However, part of the ξ_{31}^{2ν} range allowed by the QRPA is excluded by the present measurement at the 90% confidence level. Our analysis reveals that predicted ξ_{31}^{2ν} values are sensitive to the quenching of NMEs and the competing contributions from low- and high-energy states in the intermediate nucleus. Because these aspects are also at play in neutrinoless ßß decay, ξ_{31}^{2ν} provides new insights toward reliable neutrinoless ßß NMEs.

12.
BMC Vet Res ; 15(1): 205, 2019 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-31208467

RESUMO

BACKGROUND: Poultry farming is widely practiced by rural households in Vietnam and the vast majority of domestic birds are kept on small household farms. However, smallholder poultry production is constrained by several issues such as infectious diseases, including avian influenza viruses whose circulation remains a threat to public health. This observational study describes the demographic structure and dynamics of small-scale poultry farms of the Mekong river delta region. METHOD: Fifty three farms were monitored over a 20-month period, with farm sizes, species, age, arrival/departure of poultry, and farm management practices recorded monthly. RESULTS: Median flock population sizes were 16 for chickens (IQR: 10-40), 32 for ducks (IQR: 18-101) and 11 for Muscovy ducks (IQR: 7-18); farm size distributions for the three species were heavily right-skewed. Muscovy ducks were kept for long periods and outdoors, while chickens and ducks were farmed indoors or in pens. Ducks had a markedly higher removal rate (broilers: 0.14/week; layer/breeders: 0.05/week) than chickens and Muscovy ducks (broilers: 0.07/week; layer/breeders: 0.01-0.02/week) and a higher degree of specialization resulting in a substantially shorter life span. The rate of mortality due to disease did not differ much among species, with birds being less likely to die from disease at older ages, but frequency of disease symptoms differed by species. Time series of disease-associated mortality were correlated with population size for Muscovy ducks (Kendall's coefficient τ = 0.49, p-value < 0.01) and with frequency of outdoor grazing for ducks (τ = 0.33, p-value = 0.05). CONCLUSION: The study highlights some challenges to disease control in small-scale multispecies poultry farms. The rate of interspecific contact and overlap between flocks of different ages is high, making small-scale farms a suitable environment for pathogens circulation. Muscovy ducks are farmed outdoors with little investment in biosecurity and few inter-farm movements. Ducks and chickens are more at-risk of introduction of pathogens through movements of birds from one farm to another. Ducks are farmed in large flocks with high turnover and, as a result, are more vulnerable to disease spread and require a higher vaccination coverage to maintain herd immunity.


Assuntos
Criação de Animais Domésticos/métodos , Galinhas , Patos , Doenças das Aves Domésticas/epidemiologia , Fatores Etários , Animais , Fazendas/estatística & dados numéricos , Dinâmica Populacional , Doenças das Aves Domésticas/mortalidade , Doenças das Aves Domésticas/prevenção & controle , Doenças das Aves Domésticas/virologia , Vietnã
13.
Biotechnol Bioeng ; 113(12): 2614-2623, 2016 12.
Artigo em Inglês | MEDLINE | ID: mdl-27260386

RESUMO

In this study, we fabricate a functionally integrated monolithic thermoplastic microdevice for continuous operation of nucleic acid purification and amplification using polycarbonate (PC). A solid-phase-based purification and subsequent isothermal amplification, specifically, thermal helicase-dependent amplification (tHDA), was performed in a single operation in a valve-free manner. PC microdevice was assembled using modified thermal bonding process under relatively low temperature and pressure condition, realized by surface chemical modification of PC into hydrophilic property using amine-bearing polyethyleneimine (PEI). After the device sealing, only the microchannel parts were selectively modified to be hydrophobic, using epoxy-terminated poly(dimethylsiloxane) (PDMS) (epoxy-PDMS) on amine-coated surface for stepwise introduction of multiple reagents in a valve-free manner. Using the integrated PC microdevice, nucleic acids from genetically modified Escherichia coli (E. coli) O157:H7 were captured inside a chamber bearing amine functionality, by electrostatic interaction, and were subsequently amplified isothermally in the same chamber. Purified DNA captured inside the microchamber was detected directly inside the chamber by fluorescence measurement, and a 92-bp long EaeA gene, inserted into the E. coli O157:H7, was successfully amplified using the integrated PC microdevice in less than 90 min, paving the way for facile identification of foodborne pathogens with simple operation and reduced peripheral operations applicable for portable healthcare purposes. Biotechnol. Bioeng. 2016;113: 2614-2623. © 2016 Wiley Periodicals, Inc.


Assuntos
DNA Bacteriano/genética , Escherichia coli O157/isolamento & purificação , Análise de Alimentos/instrumentação , Contaminação de Alimentos/análise , Técnicas de Amplificação de Ácido Nucleico/instrumentação , Cimento de Policarboxilato/química , DNA Bacteriano/isolamento & purificação , Desenho de Equipamento , Análise de Falha de Equipamento , Escherichia coli O157/classificação , Escherichia coli O157/genética , Microbiologia de Alimentos/instrumentação , Calefação/instrumentação , Miniaturização , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Integração de Sistemas
14.
J Gen Virol ; 96(12): 3470-3483, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26407694

RESUMO

Human respiratory syncytial virus (RSV) is the major cause of lower respiratory tract infections in children ,2 years of age. Little is known about RSV intra-host genetic diversity over the course of infection or about the immune pressures that drive RSV molecular evolution. We performed whole-genome deep-sequencing on 53 RSV-positive samples (37 RSV subgroup A and 16 RSV subgroup B) collected from the upper airways of hospitalized children in southern Vietnam over two consecutive seasons. RSV A NA1 and RSV B BA9 were the predominant genotypes found in our samples, consistent with other reports on global RSV circulation during the same period. For both RSV A and B, the M gene was the most conserved, confirming its potential as a target for novel therapeutics. The G gene was the most variable and was the only gene under detectable positive selection. Further, positively selected sites inG were found in close proximity to and in some cases overlapped with predicted glycosylation motifs, suggesting that selection on amino acid glycosylation may drive viral genetic diversity. We further identified hotspots and coldspots of intra-host genetic diversity in the RSV genome, some of which may highlight previously unknown regions of functional importance.


Assuntos
Evolução Molecular , Genoma Viral/genética , Infecções por Vírus Respiratório Sincicial/veterinária , Vírus Sincicial Respiratório Humano/classificação , Vírus Sincicial Respiratório Humano/genética , Sequência de Aminoácidos , Criança , Regulação Viral da Expressão Gênica/fisiologia , Variação Genética , Genótipo , Humanos , Modelos Moleculares , Filogenia , Conformação Proteica , Infecções por Vírus Respiratório Sincicial/epidemiologia , Vietnã/epidemiologia , Proteínas Virais/genética , Proteínas Virais/metabolismo
15.
Foods ; 13(7)2024 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-38611414

RESUMO

The colour of seafood flesh is often not homogenous, hence measurement of colour requires repeat measurements to obtain a representative average. The aim of this study was to determine the optimal number of repeat colour measurements required for three different devices [machine vision (digital image using camera, and computer processing); Nix Pro; Minolta CR400 colorimeter] when measuring three species of seafood (Atlantic salmon, Salmo salar, n = 8; rockling, Genypterus tigerinus, n = 8; banana prawns, Penaeus merguiensis, n = 105) for raw and cooked samples. Two methods of analysis for number of repeat measurements required were compared. Method 1 was based on minimising the standard error of the mean and Method 2 was based on minimising the difference in colour over repeat measurements. Across species, using Method 1, machine vision required an average of four repeat measurements, whereas Nix Pro and Minolta required 13 and 12, respectively. For Method 2, machine vision required an average of one repeat measurement compared to nine for Nix Pro and Minolta. Machine vision required fewer repeat measurements due to its lower residual variance: 0.51 compared to 3.2 and 2.5 for Nix Pro and Minolta, respectively. In conclusion, machine vision requires fewer repeat measurements than colorimeters to precisely measure the colour of salmon, prawns, and rockling.

16.
Meat Sci ; 209: 109395, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38141536

RESUMO

Variations in pork quality impact consumer acceptance, and fibre type differences between muscles contribute to this variation. The aim was to investigate the influence of variations in muscle fibre types and protein denaturation peaks across four pork muscles and the influence of ageing and cooking temperature on longissimus quality traits. The longissimus, masseter, cutaneous trunci, and psoas major from 13 carcases were removed 1-day postmortem and subjected to 0- or 14-days ageing (d0, d14). Quality traits, protein denaturation peak temperature (DSC), fibre diameter and fibre type proportions were measured. Cook loss for longissimus was similar on d0 and d14, but was higher on d14 for masseter, cutaneous trunci, and psoas major. Warner-Bratzler shear force was highest, and ultimate pH was lowest, for longissimus, and similar among cutaneous trunci, masseter, and psoas major. Masseter had lowest L* and highest a* and longissimus and cutaneous trunci had highest L* and lowest a*. The DSC temperature peaks for longissimus occurred at lower temperatures relative to the other muscles. Fibre diameter was largest for type-IIb fibres relative to type-IIa and type-I. Longissimus and cutaneous trunci had predominantly type-IIb glycolytic (71%, 51% respectively), masseter had predominantly type-IIa intermediate (50%) and psoas major had predominantly type-I oxidative (48%) fibres. The glycolytic longissimus had the lowest DSC temperature peaks and the lowest quality meat. Masseter had the highest proportion of type-I fibres but was generally similar in quality traits to psoas major, and also similar to cutaneous trunci which had more glycolytic fibres than masseter.


Assuntos
Carne de Porco , Carne Vermelha , Animais , Suínos , Músculo Esquelético/metabolismo , Temperatura , Desnaturação Proteica , Fibras Musculares Esqueléticas/metabolismo , Culinária , Músculos Psoas
17.
Food Chem ; 460(Pt 1): 140506, 2024 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-39053267

RESUMO

The taste of beef is caused by taste-active compounds detected in the mouth during mastication. We hypothesised that the concentration of taste-active compounds in beef is influenced by muscle-fibre-type and postmortem ageing. To test this, and unravel the underlying mechanisms, we investigated the taste-active compounds, and proteomic profiles, in beef masseter [oxidative muscle, all type I fibres) and cutaneous trunci (glycolytic muscle, mostly type II fibres) before and after 14-days postmortem ageing. Our results showed that nucleotides were initially higher and degraded slower in cutaneous trunci (P < 0.05 for both), which could be explained by the profile of nucleotide metabolism enzymes. In contrast, free amino acids were initially higher and increased more in masseter compared to cutaneous trunci (P < 0.05 for all), which might be explained by the profile and activity of proteases in these two muscles. Our results indicate the taste of beef is affected by the muscle-fibre-type and postmortem ageing.


Assuntos
Proteômica , Paladar , Bovinos/metabolismo , Animais , Fibras Musculares Esqueléticas/metabolismo , Metabolômica , Carne Vermelha/análise , Humanos , Mudanças Depois da Morte , Aromatizantes/metabolismo , Aromatizantes/química
18.
Plant Sci ; 339: 111935, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38049038

RESUMO

Manganese (Mn), an indispensable plant micronutrient, functions as a vital enzyme co-factor in numerous biochemical reactions. In rice, the Golgi-localized PHOTOSYNTHESIS-AFFECTED MUTANT 71-LIKE 3 (OsPML3), a member of the UNCHARACTERIZED PROTEIN FAMILY (UPF0016), plays a pivotal role in Mn homeostasis, particularly in rapidly developing tissues. This study focused on the functional characterization of another UPF0016 family member in rice, OsPML4, to elucidate its involvement in Mn homeostasis. OsPML4 had a 73% sequence identity with OsPML3 and exhibited expression in both shoots and roots, albeit at a lower transcriptional level than OsPML3. Furthermore, subcellular localization studies confirmed that OsPML4 localizes in the Golgi apparatus. Notably, heterologous expression of OsPML4 restored growth in the Mn uptake-deficient yeast strain Δsmf1 under Mn-limited conditions. Under Mn-deficient conditions, OsPML4 knockout exacerbated the decline in shoot dry weight and intensified necrosis in young leaves of OsPML3 knockout lines, which displayed stunted growth. The Mn concentration in OsPML3PML4 double knockout lines was lower than in wild-type (WT) and OsPML3 knockout lines. At the reproductive phase, OsPML3PML4 double knockout lines exhibited reduced fertility and grain yield compared to WT and OsPML3 knockout lines. Notably, reductions were observed in the deposition of cell wall polysaccharides and the content of Lea (Lewis A structure)-containing N-glycans in the young leaves of OsPML3PML4 double knockout lines, surpassing the reductions in WT and OsPML3 knockout lines. These findings underscore the significance of OsPML4 in Mn homeostasis in the Golgi apparatus, where it co-functions with OsPML3 to regulate cell wall polysaccharide deposition and late-stage Golgi N-glycosylation.


Assuntos
Proteínas de Transporte de Cátions , Oryza , Manganês/metabolismo , Oryza/genética , Oryza/metabolismo , Complexo de Golgi/metabolismo , Homeostase , Saccharomyces cerevisiae/metabolismo , Proteínas de Transporte de Cátions/metabolismo
19.
Meat Sci ; 218: 109631, 2024 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-39167994

RESUMO

Pork eating quality is affected by various factors. In this study, Longissimus thoracis et lumborum (LTL) and Semimembranosus (SM) muscles from seven genetic lines (PM-LR - Pure maternal, Landrace-type; PM-LW - Pure maternal, Large White-type; PM-D - Pure maternal, Duroc-type; PT-D - Pure terminal, Duroc-type; PT-LW - Pure terminal, Large White-type; PT-LR - Pure Terminal, Landrace-type; Comp-P × LW × D - Composite Terminal - Pietran × Large white × Duroc) were analyzed for pH, intramuscular fat (IMF) content, and collagen content and solubility. A consumer sensory test using check-all-that-apply (CATA) and biometric approaches was also conducted. The results showed that the IMF content of line PM-D was the highest (P = 0.004), while line PT-LW received the highest score in tenderness, liking of flavor, purchase intent, and quality grading (P < 0.05). Line PM-LR and PT-LR showed the lowest IMF content and were least preferred by consumers. Compared to LTL, SM showed higher pH, collagen solubility, and sensory scores in tenderness, juiciness, liking of flavor, and overall liking (P < 0.05). Different muscles and lines were associated with different CATA terms but not with differences in consumer emotional responses. pH positively influenced tenderness, juiciness, and overall liking (P < 0.05), but IMF and collagen had little effect. The flavor was the most important sensory attribute contributing to overall liking, followed by tenderness. Genetic line and muscle affected pork chemical properties and eating quality. The findings are important for the Australian pork industry to improve the eating quality of their products.

20.
J Anim Sci ; 1022024 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-39177492

RESUMO

In this study, pigs from 3 supply chains were slaughtered in an Australian summer and winter (n = 20 for each supply chain). The pigs were from 2 sexes (female and castrated male) and 2 carcass weight groups (high: 95.0 to 100.0 kg and low: 75.0 to 80.0 kg). From each carcass, the Biceps femoris (BF), Longissimus thoracis et lumborum (LTL), and Triceps brachii (TB) were excised at 24 h postmortem, vacuum packed, frozen at 24-48 h and transported to the lab. Cooking loss, Warner-Bratzler shear force (WBSF) and texture profile analysis (adhesiveness, chewiness, cohesiveness, hardness, resilience, and springiness) were measured in LTL and BF. pH, collagen content, and solubility and intramuscular fat (IMF) content were determined for all muscles. Results showed that BF was tougher than LTL, and winter samples were tougher than summer ones (P < 0.05). The TB had higher pH, collagen, and IMF content than BF and LTL (P < 0.05). Collagen solubility was higher in castrated male and winter samples. pH, collagen solubility, and IMF content were significantly (P < 0.05) related to chewiness and hardness in pork BF and LTL. pH and IMF were also related to cooking loss, while collagen solubility and IMF were related to WBSF (P < 0.05). The relationships of pH and IMF with pork texture were predominantly driven by the LTL, while the relationships between collagen solubility and texture were predominantly driven by the BF. Collagen solubility and IMF of pork BF and TB were related to those of LTL, but the correlations were not strong enough for prediction. Pork texture and chemical components were affected by muscle, seasons, sex and carcass weight. pH, collagen solubility, and IMF-affected pork texture.


Pork quality was affected by the season, sex, and weight of the pigs and muscle type. In this study, we determined how season, sex, weight, and muscle affected pork chemical components and texture and, how pH, collagen and intramuscular fat affected pork texture. The results showed that pork silverside was tougher than the loin, while pork collected during winter was tougher than that collected during summer. The pork shoulder had higher pH, intramuscular fat, and collagen content than silverside and loin. Pork with higher pH, collagen solubility, and intramuscular fat content would be the tenderest.


Assuntos
Tecido Adiposo , Colágeno , Músculo Esquelético , Estações do Ano , Animais , Masculino , Feminino , Colágeno/química , Colágeno/metabolismo , Músculo Esquelético/química , Músculo Esquelético/fisiologia , Suínos/fisiologia , Peso Corporal , Fatores Sexuais , Carne/análise , Carne/normas , Culinária
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