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The skin is subjected to various external factors that contribute to aging including oxidative stress from hydrogen peroxide (H2O2). This study investigated the distribution of aquaporin-8 (AQP8), a protein that transports H2O2 across biological membranes, in skin cells, and its effects in mitigating H2O2-induced oxidative damage. Human dermal fibroblasts were treated with increasing concentrations of H2O2 to evaluate oxidative damage. Cell viability, reactive oxygen species (ROS) generation, and the expression of specific genes associated with skin aging (IL-10, FPR2, COL1A1, KRT19, and Aggrecan) were evaluated and AQP8 expression was assessed via quantitative polymerase chain reaction and western blotting. Small-interfering RNA was used to silence the AQP8 gene and evaluate its significance. The results show that H2O2 treatment reduces cell viability and increases ROS generation, leading to oxidative damage that affects the expression of target molecules. Interestingly, H2O2-treated cells exhibit high levels of AQP8 expression and gene silencing of AQP8 reverses high levels of ROS and low levels of COL1A1, KRT19, and Aggrecan expression in stressed cells, indicating that AQP8 plays a vital role in preventing oxidative damage and consequent aging. In conclusion, AQP8 is upregulated in human dermal fibroblasts during H2O2-induced oxidative stress and may help prevent oxidative damage and aging. These findings suggest that AQP8 could be a potential therapeutic target for skin aging. Further research is necessary to explore the feasibility of using AQP8 as a preventive or therapeutic strategy for maintaining skin health.

To enhance the liquid nitrogen freezing efficiency and improve the quality of frozen prepared Monopterus albus, the effect of variable temperature liquid nitrogen quick-freezing combined with composite cryoprotectant treatment on the quality of prepared M. albus was investigated. Deep-fried cured M. albus was treated with a novel composite cryoprotectant consisting of 4% xylooligosaccharides, 4% sorbitol and 0.3% sodium bicarbonate before precooling followed by liquid nitrogen freezing at variable temperatures (from -80 to -50 ℃). Internal temperature, moisture content, thawing loss, centrifugal loss, moisture state, thiobarbituric reactive substances (TBARS) value, acid value (AV), fluorescent compound content, and total volatile basic nitrogen (TVB-N) content were measured, and ice crystal morphology and microstructure were observed. The results indicated significantly lower thawing loss (3.80%), centrifugal loss (11.6%) and free water percentage (24.4%) under variable temperature liquid nitrogen quick-freezing compared with freezer freezing (P 0.05). These findings suggested that pre-cooling followed by variable temperature liquid nitrogen quick-freezing combined with the novel composite cryoprotectant could enhance the quality of prepared M. albus during frozen storage, which will offer theoretical support for the development of highly efficient freezing and preservation technology for prepared M. albus products.

Xiao Lin,1 Dan Xiong,1 Yi-Qun Peng,1 Zhi-Feng Sheng,1 Xi-Yu Wu,1 Xian-Ping Wu,1 Feng Wu,2 Ling-Qing Yuan,1 Er-Yuan Liao1 1Institute of Metabolism and Endocrinology, 2Department of Pathology, The Second Xiangya Hospital, Central South University, Changsha, Hunan, People’s Republic of China Abstract: With the progressive aging of the population, osteoporosis has gradually grown into a global health problem for men and women aged 50 years and older because of its consequences in terms of disabilities and fragility fractures. This is especially true in the People’s Republic of China, which has the largest population and an increasing proportion of elderly people, as osteoporosis has become a serious challenge to the Chinese government, society, and family. Apart from the fact that all osteoporotic fractures can increase the patient’s morbidity, they can also result in fractures of the hip and vertebrae, which are associated with a significantly higher mortality. The cost of osteoporotic fractures, moreover, is a heavy burden on families, society, and even the country, which is likely to increase in the future due, in part, to the improvement in average life expectancy. Therefore, understanding the epidemiology of osteoporosis is essential and is significant for developing strategies to help reduce this problem. In this review, we will summarize the epidemiology of osteoporosis in the People’s Republic of China, including the epidemiology of osteoporotic fractures, focusing on preventive methods and the management of osteoporosis, which consist of basic measures and pharmacological treatments. Keywords: osteoporosis, fracture, epidemiology, management

Yu-Ting Chin,1 En-Chih Liao,2 Chia-Che Wu,1 Gou-Jen Wang,1,3,4 Jaw-Ji Tsai2 1Department of Mechanical Engineering, National Chung-Hsing University, 2Department of Medical Education and Research, Taichung Veterans General Hospital, 3Graduate Institute of Biomedical Engineering, 4PhD Program in Tissue Engineering and Regenerative Medicine, National Chung-Hsing University, Taichung, Taiwan Abstract: Group 2 allergens (Der p2) have been reported to be a major cause of the human immune response to dust mite allergens. In this study, we have demonstrated for the first time the effective differentiation between haplotype mutation and normal genes in the MD-2 gene promoter using a nanostructured biosensor. A 70-mer gene fragment containing the haplotype of two single nucleotide polymorphisms in the MD-2 gene promoter region was used as a probe to detect haplotype mutations associated with Der p2-induced allergy. Discrimination was achieved using electrochemical impedance spectroscopy. The discrimination experiments employed 30 haplotype mutation samples and 30 normal target samples. The haplotype mutation samples and normal target samples could be clearly discriminated, even using samples produced by a five-cycle polymerase chain reaction process. The time and cost of sample preparation for the polymerase chain reaction process in the clinical setting can thus be reduced. Keywords: haplotype mutation detection, nanostructured biosensor, MD-2 gene promoter, electrochemical impedance spectroscopy

Groundnut, a nutrient-rich food legume, is cultivated world over. It is valued for its good quality cooking oil, energy and protein rich food, and nutrient-rich fodder. Globally, groundnut improvement programs have developed varieties to meet the preferences of farmers, traders, processors and consumers. Enhanced yield, tolerance to biotic and abiotic stresses and quality parameters have been the target traits. Spurt in genetic information of groundnut was facilitated by development of molecular markers, genetic and physical maps, generation of expressed sequence tags (EST), discovery of genes, and identification of quantitative trait loci (QTL) for some important biotic and abiotic stresses and quality traits. The first groundnut variety developed using marker assisted breeding (MAB) was registered in 2003. Since then, USA, China, Japan, and India have begun to use genomic tools in routine groundnut improvement programs. Introgression lines that combine foliar fungal disease resistance and early maturity were developed using MAB. Establishment of marker-trait associations (MTA) paved way to integrate genomic tools in groundnut breeding for accelerated genetic gain. Genomic Selection (GS) tools are employed to improve drought tolerance and pod yield, governed by several minor effect QTLs. Draft genome sequence and low cost genotyping tools such as genotyping by sequencing (GBS) are expected to accelerate use of genomic tools to enhance genetic gains for target traits in groundnut.

Proanthocyanidins (PAs) are a group of natural phenolic compounds that have a great effect on both flavour and nutritious value of fruit. It has been shown that PA synthesis is regulated by R2R3-MYB transcription factors (TFs) via activation of PA-specific pathway genes encoding leucoanthocyanidin reductase (LAR) and anthocyanidin reductase (ANR). Here, we report the isolation and characterization of a MYB gene designated PpMYB7 in peach. The peach PpMYB7 represents a new group of R2R3-MYB genes regulating PA synthesis in plants. It is able to activate transcription of PpLAR1 but not PpANR, and has a broader selection of potential bHLH partners compared with PpMYBPA1. Transcription of PpMYB7 can be activated by the peach basic leucine-zipper 5 TF (PpbZIP5) via response to ABA. Our study suggests a transcriptional network regulating PA synthesis in peach, with the results aiding the understanding of the functional divergence between R2R3-MYB TFs in plants.

Proanthocyanidins (PAs) are the major component of phenolics in apple, but mechanisms involved in PA biosynthesis remain unclear. Here, the relationship between the PA biosynthesis and the expression of genes encoding leucoanthocyanidin reductase (LAR) and anthocyanidin reductase (ANR) was investigated in fruit skin of one apple cultivar and three crabapples. Transcript levels of LAR1 and ANR2 genes were significantly correlated with the contents of catechin and epicatechin, respectively, which suggests their active roles in PA synthesis. Surprisingly, transcript levels for both LAR1 and LAR2 genes were almost undetectable in two crabapples that accumulated both flavan-3-ols and PAs. This contradicts the previous finding that LAR1 gene is a strong candidate regulating the accumulation of metabolites such as epicatechin and PAs in apple. Ectopic expression of apple MdLAR1 gene in tobacco suppresses expression of the late genes in anthocyanin biosynthetic pathway, resulting in loss of anthocyanin in flowers. Interestingly, a decrease in PA biosynthesis was also observed in flowers of transgenic tobacco plants overexpressing the MdLAR1 gene, which could be attributed to decreased expression of both the NtANR1 and NtANR2 genes. Our study not only confirms the in vivo function of apple LAR1 gene, but it is also helpful for understanding the mechanism of PA biosynthesis.

This purpose of this study was to evaluate the effect of pre-drying on the oil penetration and texture characteristics of deep-fried battered and breaded fish nuggets. Battered breaded fish nuggets (BBFNs) were dried in a drying oven and dried at 40 ℃ for 3, 4.5, 6, 7.5 and 9 h and deep fried at 180 ℃ for 60 s. Moisture state in dried BBFNs and deep-fried BBFNs was measured, and the oil content and distribution, microstructure and texture characteristics of deep-fried BBFNs were analyzed. The absorption of oil during deep-fat frying was simulated. The results showed that after deep-fat frying, the contents of strongly bound water (T21), weakly bound water (T22) and free water (T23) in the crust, the content of strongly bound water in the fish nuggets, the content of weakly bound water inside muscle fibers, and the content of free content outside muscle fibers were reduced. As the drying time increased, the starting time of peak T22 for the deep-fried crust gradually decreased, indicating declined freedom degree of water, and the signal intensity of peaks T21 and T22 decreased, suggesting that the bound water was converted to free water. In addition, only fish nuggets with 9 h drying showed a left shift in peak T22. The surface oil (SO) and total oil (TO) contents of deep-fried BBFNs decreased while the penetrated surface oil (PSO) content increased. The crust structure was first tight and then became rough, and the surface of the fish was smooth first and then exhibited cracks and holes. The fluorescence intensity of the crust became weaker gradually. The Sudan red-dyed region in the crust decreased while that of the junction between the crust and the fish nuggets increased gradually. The hardness and crispiness of the crust first decreased and then increased, while the elasticity and chewiness of the fish nuggets presented the opposite trend. These results indicated that pre-drying alleviated the freedom degree of moisture in BBFNs, and changed the microscopic structure of deep-fried BBFNs, thereby affecting the oil penetration and texture characteristics. The study may provide a theoretical basis and scientific guidance for the large-scale production of low-fat deep-fried BBFNs.

In recent years, ultrasound has been widely used in the food industry as a promising non-thermal, green technology, but the exact effect of ultrasound on the physicochemical properties of myofibrillar proteins from Procambarus clarkii is not clear yet. This study investigated the effect of high-intensity ultrasound treatment at 300 W power and 20 kHz frequency for 0, 4, 8, 12 and 16 min during homogenization on the structure and physicochemical properties of myofibrillar proteins from Procambarus clarkii. The results showed that ultrasound treatment decreased the turbidity and mean particle size of myofibrillar proteins significantly (P < 0.05), but initially increased and then decreased the solubility and absolute value of ζ-potential, demonstrating altered degree of protein aggregation. The surface hydrophobicity and endogenous fluorescence intensity initially increased and then decreased with increasing treatment time; the total sulfhydryl group content significantly decreased (P < 0.05) while the carbonyl group content significantly increased (P < 0.05), demonstrating changes in the tertiary structure and a certain degree of protein denaturation. In addition, the relative contents of α-helix and random coil increased first and then decreased, whereas the opposite trend was observed for the proportion of β-sheet, indicating changes in the secondary structure. These results showed that high-intensity ultrasound treatment could affect the physicochemical properties, structure and aggregation degree of myofibrillar proteins from crayfish meat, which could provide a reference for the application of ultrasound as an auxiliary approach in the processing and storage of crayfish.

This study was executed in order to investigate quality deterioration caused by lipid oxidation during the frozen storage of Acipenser sinensis. Fish pieces were stored at −18 ℃ for 24 weeks after being frozen using a freezer (−20 or −50 ℃) or liquid nitrogen (−80 or −110 ℃). The central temperature, fat and free fatty acid (FFA) contents, fatty acid composition, peroxide value (POV), thiobarbituric reactive substance (TBARS) value, and fluorescent compound content were measured and the microstructure of muscle fibers was also observed during the storage period for the purpose of evaluating the influence of freezing methods on lipid oxidation and muscle microstructure in Acipenser sinensis during frozen storage. The results showed that with increasing storage time, the fat and polyunsaturated fatty acid (PUFA) contents of the four fish samples decreased, while POV, TBARS value, and the contents of FFAs, saturated fatty acids (SFAs), monounsaturated fatty acids (MUFAs) and fluorescent compounds increased. The gap between muscle fibers increased, which was accompanied by breaking of myofibrils. In addition, the contents of fat and PUFAs in liquid nitrogen frozen samples were significantly higher than those in freezer frozen ones (at the end of storage, the freezer frozen sample frozen at −20 ℃ contained 7.89% of fat compared to 9.13% for the liquid nitrogen frozen one at −80 ℃), while POV, TBARS value, and the contents of FFAs, SFAs, MUFAs and fluorescent compounds were significantly lower than those in freezer frozen samples (P < 0.05), and the muscle fiber structure was more complete. The above results indicated that liquid nitrogen frozen alleviated the degree of myofibrillar damage and lipid hydrolysis in Acipenser sinensis during frozen storage, thereby reducing the speed of lipid oxidation.

To investigate the effect of dietary fiber on batter characteristics and oil penetration in deep-fried battered and breaded fish nuggets (BBFNs) from silver carp surimi, deep-fried BBFNs were prepared with model batters (composed of wheat starch and gluten) added with 8% apple fiber, 6% soybean fiber or 12% wheat bran fiber. The moisture adsorption isotherms of dietary fiber, wheat starch and gluten, and the pick-up of BBFNs were evaluated, the viscosity, rheological behavior and calorimetric properties of batters were measured, and the thermogravimetric properties of the crust, the water state and oil penetration of deep-fried BBFNs were also evaluated. The results showed that the moisture absorption capacity of wheat starch was the largest, followed by soybean fiber, apple fiber, wheat bran fiber, and gluten. Compared to that the control group (without dietary fiber), the addition of 8% apple fiber, 6% soybean fiber or 12% wheat bran fiber significantly increased the viscosity of batters and the pick-up of BBFNs (P < 0.05). The loss modulus (G’) and storage modulus (G”) of batters were decreased firstly, then increased rapidly and ultimately remained stable with an increase in oil temperature, and soybean fiber resulted in the highest G’ and G”, which contributed to the fastest formation of gels and the highest thermal stability of the crust after frying. The addition of each of the dietary fibers resulted in transformation of free water into bound water and increased the total moisture content of the crust. Soybean fiber resulted in the lowest oil penetration in deep-fried BBFNs, followed by apple fiber, wheat bran fiber and the control group. This study indicated that the addition of the three dietary fibers in model batter systems can accelerate the formation of gels, significantly improve the strength of the gels formed, and ultimately inhibit oil penetration in deep-fried BBFNs.

This study addressed the effect of polysaccharide hydrocolloids on the crust characteristics and oil penetration of fried battered and breaded fish nuggets (BBFNs). Fish pieces were battered with a mixture of wheat starch (WS) and wheat gluten (WG) at a ratio of 11:1 (m/m) added with 0.3% sodium carboxymethyl cellulose (CMC-Na), 0.2% guar gum (GG), or 0.2% xanthan gum (XG), breaded, and fried at 170 ℃ for 40 s followed by 190 ℃ for 30 s. The fluorescence intensity, surface hydrophobicity (H0), sulfydryl and disulfide bond contents, and secondary structure of WG and the crystal structure of WS in the crust were determined, and the oil penetration in the crust was evaluated. Results showed that the H0, fluorescence intensity, disulfide bond content, relative contents of β-sheet and β-turn in the crusts with the three polysaccharide hydrocolloids were greater than those in the control (without the addition of any polysaccharide hydrocolloids), while the free sulfydryl content and the relative contents of α-helix and random coil of WG, and the relative crystallinity of WS were lower than those in the control. The H0, fluorescence intensity, sulfydryl content and relative α-helix content of WG and the relative crystallinity of WS were lowest for the crust with XG, followed by CMC-Na and GG, while an opposite trend was observed for the disulfide bond content and relative β-sheet content. Furthermore, Sudan red staining area was largest for the control, and smallest for fried BBFNs with XG (present only in the crust), followed by CMC-Na and GG. These results indicated that due to their high hydrophilicity and unique structures, the three polysaccharide hydrocolloids can interact with WG to improve the stability of the crust, thereby inhibiting the oil penetration of fried BBFNs.

In the present study, the effect of the interaction between wheat starch and gluten on oil distribution in deep-fried battered and breaded fish nuggets (BBFNs) from silver carp surimi was investigated. Deep-fried BBFNs were prepared using batters consisting of wheat starch (WS) and gluten (WG) blends (at mass ratios of 15:1, 13:1, 11:1, 9:1 and 7:1), and then the surface hydrophobicity (H0), free sulfydryl content, disulfide bond content, secondary structure of WG and the crystalline structure of WS in the crust, as well as the surface oil and penetrated surface oil contents of deep-fried BBFNs were evaluated. The microstructure and oil distribution in the crust were also observed. The results showed that as the WS/WG ratio decreased, the H0 value increased firstly then decreased, and the free sulfydryl and disulfide bond contents gradually decreased and increased, respectively. Meanwhile, the β-turn structure of WG was gradually converted into β-sheet, and the surface oil and penetrated surface oil contents of deep-fried BBFNs as well as the relative crystallinity of WS decreased firstly then increased. The size of pores in the crust and oil distribution decreased at first and then increased. Among the tested WS/WG ratios, deep-fried BBFNs with a WS/WG ratio of 11:1 had the highest H0 (8 990), and the lowest surface oil (2.1%) and penetrated surface oil contents (5.8%), and the lowest relative crystallinity of WS (17.8%), and the crust exhibited the most compact microstructure and the least oil distribution. Therefore, the interaction between WS and WG is affected by changes in WS/WG ratio, which can in turn affect oil distribution in deep-fried BBFNs.