One-pot Twostep Chemobiocatalytic Synthesis of a Furan Amino Acid from 5-Hydroxymethylfurfural.

Recently, catalytic valorization of biomass-derived furans has received growing interest. 5-Aminomethyl-2-furancarboxylic acid (AMFC), a furan amino acid, holds great promise in the aeras of polymer and pharmaceutical, but its synthesis remains limited. In this work, we report a chemobiocatalytic route toward AMFC by combining laccase-TEMPO system and recombinant Escherichia coli (named E. coli_TAF) harboring ω-transaminase (TA), L-alanine dehydrogenase (L-AlaDH) and formate dehydrogenase (FDH), starting from 5-hydroxymethylfurfural (HMF). In the cascade, HMF is oxidized into 5-formyl-2-furancarboxylic acid (FFCA) by laccase-TEMPO system, and then the resulting intermediate is converted into AMFC by E. coli_TAF via transamination with cheap ammonium formate instead of costly organic amine donors, theoretically generating H2O and CO2 as by-products. The tandem process was run in a one-pot twostep manner, affording AMFC with approximately 81 % yield, together with 10 % 2,5-furandicarboxylic acid (FDCA) as by-product. In addition, the scale-up production of AMFC was demonstrated, with 0.41 g/L h productivity and 8.6 g/L titer. This work may pave the way for green manufacturing of the furan-containing amino acid.

Ultrasound radiomics-based nomogram to predict lymphovascular invasion in invasive breast cancer: a multicenter, retrospective study.

OBJECTIVES: To develop and validate an ultrasound (US) radiomics-based nomogram for the preoperative prediction of the lymphovascular invasion (LVI) status in patients with invasive breast cancer (IBC). MATERIALS AND METHODS: In this multicentre, retrospective study, 456 consecutive women were enrolled from three institutions. Institutions 1 and 2 were used to train (n = 320) and test (n = 136), and 130 patients from institution 3 were used for external validation. Radiomics features that reflected tumour information were derived from grey-scale US images. The least absolute shrinkage and selection operator and the maximum relevance minimum redundancy (mRMR) algorithm were used for feature selection and radiomics signature (RS) building. US radiomics-based nomogram was constructed by using multivariable logistic regression analysis. Predictive performance was assessed with the receiving operating characteristic curve, discrimination, and calibration. RESULTS: The nomogram based on clinico-ultrasonic features (menopausal status, US-reported lymph node status, posterior echo features) and RS yielded an optimal AUC of 0.88 (95% confidence interval [CI], 0.84-0.91), 0.89 (95% CI, 0.84-0.94) and 0.95 (95% CI, 0.92-0.99) in the training, internal and external validation cohort. The nomogram outperformed the clinico-ultrasonic and RS model (p < 0.05). The nomogram performed favourable discrimination (C-index, 0.88; 95% CI: 0.84-0.91) and was confirmed in the validation (0.88 for internal, 0.95 for external) cohorts. The calibration and decision curve demonstrated the nomogram showed good calibration and was clinically useful. CONCLUSIONS: The radiomics nomogram incorporated in the RS and US and the clinical findings exhibited favourable preoperative individualised prediction of LVI. CLINICAL RELEVANCE STATEMENT: The US radiomics-based nomogram incorporating menopausal status, posterior echo features, US reported-ALN status, and radiomics signature has the potential to predict lymphovascular invasion in patients with invasive breast cancer. KEY POINTS: • The clinico-ultrsonic model of menopausal status, posterior echo features, and US-reported ALN status achieved a better predictive efficacy for LVI than either of them alone. • The radiomics nomogram showed optimal prediction in predicting LVI from patients with IBC (ROC, 0.88 and 0.89 in the training and validation sets). • A nomogram demonstrated favourable performance (area under the receiver operating characteristic curve, 0.95) and well calibration (C-index, 0.95) in an independent validation cohort (n = 130).

Hormone replacement therapy and periodontitis progression in postmenopausal women: A prospective cohort study.

OBJECTIVE: This study aimed to investigate the responses of periodontal environment to hormone replacement therapy (HRT) in postmenopausal women with or without periodontitis. BACKGROUND: HRT is a common and effective strategy for controlling menopausal symptoms, while the changes of periodontal environment under it, particularly in postmenopausal women with periodontitis, remain unclear. METHODS: As a prospective cohort study, a total of 97 postmenopausal women receiving HRT were screened, including 47 with and 50 without periodontitis. Correspondingly, 97 women did not receiving HRT were screened as controls during the same period. The full-mouth sulcus bleeding index (SBI), bleeding on probing (BOP), probing pocket depth (PPD), and clinical attachment level (CAL) were measured using periodontal probes. The levels of interleukin-6 (IL-6) and tumor necrosis factor α (TNF-α) in the gingival crevicular fluid were measured using enzyme-linked immunosorbent assay. In addition, cone beam computed tomography was performed to measure the alveolar bone height (ABH) and bone mineral density (BMD). RESULTS: In postmenopausal women without periodontitis, no significantly changes on periodontal parameters were observed after HRT. In women with stage II periodontitis, SBI, BOP, IL-6, and TNF-α were significant decreased after one year and two years of HRT. Compared to the controls, women with stage II periodontitis who underwent HRT had significantly lower CAL and ABH and higher BMD in the second year. The incidence of at least one site with CAL increase ≥1 mm between baseline and 2 years was significantly lower in the HRT group than in the control group in women with stage II periodontitis. In addition, HRT was significantly associated with a decrease in SBI, BOP, IL-6, and TNF-α in the first year and with a decrease in CAL, SBI, BOP, IL-6, and ABH and an increase in BMD in the second year. CONCLUSIONS: In postmenopausal women with stage II periodontitis, HRT is associated with the alleviation of inflammation within two years and the remission of alveolar bone loss in the second year. HRT appears to decrease the incidence of CAL increase ≥1 mm within 2 years in women with periodontitis by inhibiting inflammation and alveolar bone loss.

Sarcopenia, sarcopenic obesity and the clinical outcome of the older inpatients with COVID-19 infection: a prospective observational study.

OBJECTIVE: We aimed to investigate the impact of sarcopenia and sarcopenic obesity (SO) on the clinical outcome in older patients with COVID-19 infection and chronic disease. METHODS: We prospectively collected data from patients admitted to Huadong Hospital for COVID-19 infection between November 1, 2022, and January 31, 2023. These patients were included from a previously established comprehensive geriatric assessment (CGA) cohort. We collected information on their pre-admission condition regarding sarcopenia, SO, and malnutrition, as well as their medical treatment. The primary endpoint was the incidence of intubation, while secondary endpoints included in-hospital mortality rates. We then utilized Kaplan-Meier (K-M) survival curves and the log-rank tests to compare the clinical outcomes related to intubation or death, assessing the impact of sarcopenia and SO on patient clinical outcomes. RESULTS: A total of 113 patients (age 89.6 ± 7.0 years) were included in the study. Among them, 51 patients had sarcopenia and 39 had SO prior to hospitalization. Intubation was required for 6 patients without sarcopenia (9.7%) and for 18 sarcopenia patients (35.3%), with 16 of these being SO patients (41%). Mortality occurred in 2 patients without sarcopenia (3.3%) and in 13 sarcopenia patients (25.5%), of which 11 were SO patients (28%). Upon further analysis, patients with SO exhibited significantly elevated risks for both intubation (Hazard Ratio [HR] 7.43, 95% Confidence Interval [CI] 1.26-43.90, P < 0.001) and mortality (HR 6.54, 95% CI 1.09-39.38, P < 0.001) after adjusting for confounding factors. CONCLUSIONS: The prevalence of sarcopenia or SO was high among senior inpatients, and both conditions were found to have a significant negative impact on the clinical outcomes of COVID-19 infection. Therefore, it is essential to regularly assess and intervene in these conditions at the earliest stage possible.

Psychometric properties of the Chinese version of the 15-item Need for Closure Scale: Scale validation and associations with mental health.

BACKGROUND: Need for closure (NFC) has been found to be implicated in different forms of psychopathology. The 15-item Need for Closure Scale (NFCS) is an efficient and easy tool for assessing individuals' NFC in Western contexts. However, the psychometric properties of the 15-item NFCS have not yet been validated in Chinese populations. METHODS: Two different samples of university students from China were recruited in this study. The first sample (N = 5080, 49.9% females) was used to conduct exploratory factor analysis and reliability analysis. The second sample (N = 3968, 64.2% females) was used to perform confirmatory factor analysis, exploratory structural equation modeling (ESEM), and bifactor models, followed by tests of measurement invariance and criterion validity. RESULTS: The full scale showed good internal consistency. The bifactor-ESEM result with a general factor and four specific factors was chosen as our final model. Strong measurement invariance across sex and ethnicity groups was supported. Evidence was obtained for the criterion validity of NFCS scores with respect to depression, anxiety, and psychological distress. CONCLUSION: The Chinese NFCS appears to be a valid and reliable instrument for measuring the NFC, which could promote both the assessment and research of the NFC in Chinese populations.

Competitive fitness and homologous recombination of SARS-CoV-2 variants of concern.

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) variants continue to emerge and cocirculate in humans and wild animals. The factors driving the emergence and replacement of novel variants and recombinants remain incompletely understood. Herein, we comprehensively characterized the competitive fitness of SARS-CoV-2 wild type (WT) and three variants of concern (VOCs), Alpha, Beta and Delta, by coinfection and serial passaging assays in different susceptible cells. Deep sequencing analyses revealed cell-specific competitive fitness: the Beta variant showed enhanced replication fitness during serial passage in Caco-2 cells, whereas the WT and Alpha variant showed elevated fitness in Vero E6 cells. Interestingly, a high level of neutralizing antibody sped up competition and completely reshaped the fitness advantages of different variants. More importantly, single clone purification identified a significant proportion of homologous recombinants that emerged during the passage history, and immune pressure reduced the frequency of recombination. Interestingly, a recombination hot region located between nucleotide sites 22,995 and 28,866 of the viral genomes could be identified in most of the detected recombinants. Our study not only profiled the variable competitive fitness of SARS-CoV-2 under different conditions, but also provided direct experimental evidence of homologous recombination between SARS-CoV-2 viruses, as well as a model for investigating SARS-CoV-2 recombination.

Bifidobacterium spp. as functional foods: A review of current status, challenges, and strategies.

Members of Bifidobacterium are among the first microbes to colonize the human intestine naturally, their abundance and diversity in the colon are closely related to host health. Recently, the gut microbiota has been gradually proven to be crucial mediators of various metabolic processes between the external environment and the host. Therefore, the health-promoting benefits of Bifidobacterium spp. and their applications in food have gradually been widely concerned. The main purpose of this review is to comprehensively introduce general features, colonization methods, and safety of Bifidobacterium spp. in the human gut, highlighting its health benefits and industrial applications. On this basis, the existing limitations and scope for future research are also discussed. Bifidobacteria have beneficial effects on the host's digestive system, immune system, and nervous system. However, the first prerequisite for functioning is to have enough live bacteria before consumption and successfully colonize the colon after ingestion. At present, strain breeding, optimization (e.g., selecting acid and bile resistant strains, adaptive evolution, high cell density culture), and external protection technology (e.g., microencapsulation and protectants) are the main strategies to address these challenges in food application.

Effects of whey protein complex combined with low-intensity exercise in elderly inpatients with COPD at a stable stage.

BACKGROUND AND OBJECTIVES: Previous literature mostly has demonstrated the efficacy of pulmonary rehabilitation (PR) combined with whole nutrition powder in patients with chronic obstructive pulmonary disease (COPD). However, the benefits of whey protein as an oral nutritional supplement (ONS) during PR are not clear. METHODS AND STUDY DESIGN: It took 12 weeks to complete the trial, we divided 90 elderly patients with stable-stage COPD into a low-intensity exercise group (n= 30, PR group), PR plus whey proteins complex group (n= 30, PRWP group), and a control group (n= 30) randomly, and assessed index such as exercise capacity, mental health status, lung function, and body composition. Eventually, 84 people persisted until the end of the trial. RESULTS: Compared with the control group, hand grip strength (HGS)(1.4 ± 0.6 kg, and 1.0 ± 0.2 kg respectively, p< 0.05) in the PRWP and PR group, 6 minutes of walking distance (6MWD)(14.1 ± 3.8m, p< 0.05) in PRWP group improved. Furthermore, compared with the PR group, Medical Research Council Dyspnea Scale (MRC)(-0.2 ± 0.1, p< 0.01), anxiety score (-1.2 ± 0.4, p< 0.01), and body weight (2.0 ± 0.8kg, p< 0.05) improved in the PRWP group. There were no inter-group differences in a fat-free mass index or appendicular skeletal muscle mass index. CONCLUSIONS: Muscle strength could be enhanced in both intervention models. Adding whey protein complex was additionally successful in rectifying dyspnea, anxiety, and weight loss caused by exercise. This rehabilitation pattern might be valuable in elderly patients with COPD.

1,4-α-Glucosidase from Fusarium solani for Controllable Biosynthesis of Silver Nanoparticles and Their Multifunctional Applications.

In the study, monodispersed silver nanoparticles (AgNPs) with an average diameter of 9.57 nm were efficiently and controllably biosynthesized by a reductase from Fusarium solani DO7 only in the presence of ß-NADPH and polyvinyl pyrrolidone (PVP). The reductase responsible for AgNP formation in F. solani DO7 was further confirmed as 1,4-α-glucosidase. Meanwhile, based on the debate on the antibacterial mechanism of AgNPs, this study elucidated in further depth that antibacterial action of AgNPs was achieved by absorbing to the cell membrane and destabilizing the membrane, leading to cell death. Moreover, AgNPs could accelerate the catalytic reaction of 4-nitroaniline, and 86.9% of 4-nitroaniline was converted to p-phenylene diamine in only 20 min by AgNPs of controllable size and morphology. Our study highlights a simple, green, and cost-effective process for biosynthesizing AgNPs with uniform sizes and excellent antibacterial activity and catalytic reduction of 4-nitroaniline.

Improving the bioaccessibility of lipophilic ingredient in its oral intestinal delivery by ultrasound and biological cross-linker.

BACKGROUND: Great efforts have been made to improve the oral bioaccessibility of lipophilic ingredients with multi-functionalities. Achieving intestinal delivery of lipophilic ingredients and their encapsulation in micelles composed of bile salts and lipid hydrolysates (i.e. fatty acids) is critical for improving oral bioaccessibility. Therefore, oil-core microcapsules are considered ideal carriers of lipophilic ingredients. Previous studies have reported oil-core/zein-shell microcapsules constructed by a one-step anti-solvent process. Still, its efficacy as an intestinal delivery system was limited because if the porous shell structure. RESULTS: Zein solution was pretreated with ultrasound and tannic acid (TA) cross-linking. Composite oil-core microcapsule (COM) with a compact shell structure was successfully prepared by using modified zein solution in the anti-solvent process. Fourier-transform infrared spectroscopy and circular dichroism analyses indicated that ultrasound and TA synergistically promote the conformational transition of zein from α-helix to ß-sheet and enhance the hydrophobic interactions among protein chains. The above changes contribute to the strengthen of shell zein network. Correspondingly, COM presents superior encapsulation efficiency and environmental stability over the simple oil-core microcapsule (SOM) prepared without the use of ultrasound and TA. Furthermore, antioxidant activity of ß-carotene was well retained during the encapsulation process. In vitro studies indicated that COM was more resistant to digestibility and acid-induced swelling. More than 87% of ß-carotene could be released in the intestine in a sustainable way. The controllable release behavior thus promoted a significant increase in bioaccessibility of ß-carotene encapsulated in COM compared to SOM (85.9% versus 48.5%). CONCLUSION: The COM generated here shows potential for bioaccessibility improvement of lipophilic ingredients. © 2022 Society of Chemical Industry.

Oral fate and stabilization technologies of lactoferrin: a systematic review.

Lactoferrin (Lf), a bioactive protein initially found in many biological secretions including milk, is regarded as the nutritional supplement or therapeutic ligand due to its multiple functions. Research on its mode of action reveals that intact Lf or its active peptide (i.e., lactoferricin) shows an important multifunctional performance. Oral delivery is considered as the most convenient administration route for this bioactive protein. Unfortunately, Lf is sensitive to the gastrointestinal (GI) physicochemical stresses and lactoferricin is undetectable in GI digesta. This review introduces the functionality of Lf at the molecular level and its degradation behavior in GI tract is discussed in detail. Subsequently, the absorption and transport of Lf from intestine into the blood circulation, which is pivotal to its health promoting effects in various tissues, and some assisting labeling methods are discussed. Stabilization technologies aiming at preserving the structural integrity and functional properties of orally administrated Lf are summarized and compared. Altogether, this work comprehensively reviews the structure-function relationship of Lf, its oral fate and the development of stabilization technologies for the enhancement of the oral bioavailability of Lf. The existing limitations and scope for future research are also discussed.

Transthoracic, thoracoabdominal, and transabdominal surgical approaches for gastric cardia adenocarcinomas: a survival evaluation based on a cohort of 7103 patients.

BACKGROUND: This study compared the survival outcomes of different surgical approaches to determine the optimal approach for gastric cardia adenocarcinoma (GCA) and aimed to standardize the surgical treatment guidelines for GCA. METHODS: A total of 7103 patients with GCA were enrolled from our previously established gastric cardia and esophageal carcinoma databases. In our database, when the epicenter of the tumor was at or within 2 cm distally from the esophagogastric junction, the adenocarcinoma was considered to originate from the cardia and was considered a Siewert type 2 cancer. The main criteria for the enrolled patients included treatment with radical surgery, no radio- or chemotherapy before the operation, and detailed clinicopathological information. Follow-up was mainly performed by telephone or through home interviews. According to the medical records, the surgical approaches included transthoracic, thoracoabdominal, and transabdominal approaches. Kaplan-Meier and Cox proportional hazards regression models were applied to correlate the surgical approach with survival in patients with GCA. RESULTS: There were marked differences in age and tumor stage among the patients who underwent the three surgical approaches (P < 0.001). Univariate analysis showed that survival was related to sex, age, tumor stage, and N stage (P < 0.001 for all). Cox regression model analysis revealed that thoracoabdominal approach (P < 0.001) and transabdominal approach (P < 0.001) were significant risk factors for poor survival. GCA patients treated with the transthoracic approach had the best survival (5-year survival rate of 53.7%), and survival varied among the different surgical approaches for different tumor stages. CONCLUSION: Thoracoabdominal approach and transabdominal approach were shown to be poor prognostic factors. Patients with (locally advanced) GCA may benefit from the transthoracic approach. Further prospective randomized clinical trials are necessary.

Acute effect of flaxseed-enriched snack bars on glycemic responses and satiety in healthy individuals.

BACKGROUND AND OBJECTIVES: The dietary glycemic index (GI) and glycemic load (GL) have garnered scholarly attention for their roles in weight management and glycemic control. Flaxseed is a good source of fiber, lignans, and omega-3 fatty acids. This study evaluated healthy individuals' acute glycemic response and satiety following the consumption of flaxseed-enriched snack bars. METHODS AND STUDY DESIGN: Nineteen healthy men and women consumed flaxseed bars or a glucose solution containing 50 g of available carbohydrates. Capillary blood glucose concentrations were obtained through the finger-prick test. The GI and GL values of the flaxseed bars were calculated using incremental area under the glucose response curve. Over 2 h, subjective satiety was examined at 0 (fasting), 15, 30, 45, 60, 90 and 120min following the consumption of flaxseed bars or saltine crackers containing 300 kcal by using a visual analogue scale (VAS). RESULTS: Compared with that of the glucose solution, the glucose concentrations of the flaxseed bars (15-90 min) were significantly lower (p<0.001). The GI and GL values of the flaxseed bars were 30.0±23.0 and 2.3±0.2, respectively. Compared with saltine cracker consumption, flaxseed bars consumption resulted in lower hunger and higher satiety. The satiety index score of the flaxseed bars was 1.6 times higher than that of the saltine crackers. CONCLUSIONS: Although further studies are warranted to evaluate the long-term effects of flaxseed-enriched snacks on glycemia and energy balance, our findings suggest that the incorporation of flaxseed into snack bars is a viable strategy for the management of obesity and diabetes.

A Versatile Competitive Coordination Strategy for Tailoring Bioactive Zeolitic Imidazolate Framework Composites.

Zeolitic imidazolate frameworks (ZIFs) serving as platforms for bioactive guest encapsulation have attracted growing attention, yet the tailoring of its architectures and bioactivity remains a major challenge. Herein, a versatile competitive coordination strategy is proposed by using amorphous zinc nucleotide gel as template for step-by-step growth of ZIFs, which enables the tailoring of bioactive ZIF composites under facile conditions. Mechanism investigation reveals that introduced nucleotide determines the hierarchical pore structure and hydrophilicity, leading to customized activity retention and stability of the resultant bioactive ZIF composites. Furthermore, nucleoside monophosphate enhances the acidic tolerance of ZIFs. To the authors' knowledge, this is the first example showing the dynamic evolution of amorphous gels to crystalline ZIFs for in situ encapsulation of enzymes with tailored catalytic performance. This study provides insights for rational design of ZIF-based biocomposites and broadens the application of bioactive metal-organic frameworks.

Fabrication of nanostructured multi-unit vehicle for intestinal-specific delivery and controlled release of peptide.

An oral multi-unit delivery system was developed by incorporating the nanoparticle (NP) into the nanofiber mat and its efficiency for intestinal-specific delivery and controlled release of a peptide (insulin) was investigated. Initially, the influence of deacetylation degree (DD) of chitosan and ionic gelation methods on the properties of NPs was studied. High DD (95%) chitosan was attributed to higher encapsulation efficiency and stability when crosslinked with polyanion tripolyphosphate. Subsequently, the multi-unit system was fabricated using a pH-sensitive polymer (sodium alginate) as the coating layer to further encapsulate the NP. Fiber mat with an average diameter of 481 ± 47 nm could significantly decrease the burst release of insulin in acidic condition and release most amount of insulin (>60%) in the simulated intestinal medium. Furthermore, the encapsulated peptide remained in good integrity. This multi-unit carrier provides the better-designed vehicle for intestinal-specific delivery and controlled release of the peptide.

What protects us against the COVID-19 threat? Cultural tightness matters.

BACKGROUND: The only previous studies that formulated a theoretical model of epidemics for psychological response relative to cultural perspectives have focused on the role of individualism-collectivism and have omitted analysis of tightness-looseness. This study explored the role of cultural tightness in relation to psychological disorders during the outbreak of the COVID-19 pandemic. METHODS: We recruited 1827 Chinese adolescents (Mage = 18.16 ± 2.23 years, 53.3% female) to participate a cross-sectional survey. Participants completed a series of questionnaires, including the scales of cultural tightness, risk perception of COVID-19 pandemic, perceived protection efficacy, anxiety and depression. A latent moderated structural equations model was used to analyse the mediating and moderating effects of risk perception regarding COVID-19, cultural tightness and perceived protection efficacy on psychological disorders. RESULTS: The results showed that greater risk perception of COVID-19 predicted greater psychological disorders, however cultural tightness moderated this positive relationship. The increase in psychological disorders with risk perception regarding COVID-19 was less pronounced among people who lived in tighter cultural areas. In addition, this moderating effect of cultural tightness was further mediated by perceived protection efficacy; that is, tight culture protects against psychological disorders by enhancing perceived protection efficacy. CONCLUSION: This study enriched the theoretical framework of cultural tightness and indicated its importance in the field of mental health and health policies. It also emphasized the importance of tight culture as a protective factor against psychological disorders in case of COVID-19 outbreaks, providing valuable practical insight into psychological prevention for COVID-19 outbreaks.

Nutritional diet plan for patients with dysphagia.

BACKGROUND AND OBJECTIVES: To present a new method of text-modified food management for patients with dysphagia that integrates the idea of food exchange. In addition to prioritizing nutrition in each recipe, the diet plan emphasizes straightforward preparation methods that balance nutrition and palatability. METHODS AND STUDY DESIGN: On the basis of the recommended intake in the Expert Consensus, the design of the texture-modified food incorporates the concept of equivalent food exchange. The plan consists of a staple food, a meat, a vegetable, a snack, and a fruit as the base units, and the volume and nutrient density of each unit is modified to meet the needs of patients with dysphagia. RESULTS: Five categories of standard portions were established, the standard portion of staple foods, milk should be used instead of water during preparation, and carbohydrate components (dextrin) should be added so that each portion provides approximately 200 Kcal of energy. The standard portion of meat, protein components (90% whey) should be added to provide approximately 14 g of protein and 150 Kcal of energy per portion. Two types of standard snacks are recommended, each serving provides 250 Kcal of energy. Vegetables and fruits provide 70 Kcal and 90 Kcal of energy. We compiled 11 recipes representative of the food exchange system and our recipe design priorities (texture modification, sufficient nutrition, color, fragrance and taste). CONCLUSIONS: The method is combined theory and practice and can be applied to clinical nutrition work to promote the nutritional intake of patients with dysphagia.

Biotechnology and bioengineering of pullulanase: state of the art and perspectives.

Pullulanase (EC 3.2.1.41) is a starch-debranching enzyme in the α-amylase family and specifically cleaves α-1,6-glycosidic linkages in starch-type polysaccharides, such as pullulan, ß-limited dextrin, glycogen, and amylopectin. It plays a key role in debranching and hydrolyzing starch completely, thus bring improved product quality, increased productivity, and reduced production cost in producing resistant starch, sugar syrup, and beer. Plenty of researches have been made with respects to the discovery of either thermophilic or mesophilic pullulanases, however, few examples meet the demand of industrial application. This review presents the progress made in the recent years from the first aspect of characteristics of pullulanases. The heterologous expression of pullulanases in different microbial hosts and the methods used to improve the expression effectiveness and the regulation of enzyme production are also described. Then, the function evolution of pullulanases from a protein engineering view is discussed. In addition, the immobilization strategy using novel materials is introduced to improve the recyclability of pullulanases. At the same time, we indicate the trends in the future research to facilitate the industrial application of pullulanases.

Hellinger distance-based stable sparse feature selection for high-dimensional class-imbalanced data.

BACKGROUND: Feature selection in class-imbalance learning has gained increasing attention in recent years due to the massive growth of high-dimensional class-imbalanced data across many scientific fields. In addition to reducing model complexity and discovering key biomarkers, feature selection is also an effective method of combating overlapping which may arise in such data and become a crucial aspect for determining classification performance. However, ordinary feature selection techniques for classification can not be simply used for addressing class-imbalanced data without any adjustment. Thus, more efficient feature selection technique must be developed for complicated class-imbalanced data, especially in the context of high-dimensionality. RESULTS: We proposed an algorithm called sssHD to achieve stable sparse feature selection applied it to complicated class-imbalanced data. sssHD is based on the Hellinger distance (HD) coupled with sparse regularization techniques. We stated that Hellinger distance is not only class-insensitive but also translation-invariant. Simulation result indicates that HD-based selection algorithm is effective in recognizing key features and control false discoveries for class-imbalance learning. Five gene expression datasets are also employed to test the performance of the sssHD algorithm, and a comparison with several existing selection procedures is performed. The result shows that sssHD is highly competitive in terms of five assessment metrics. In addition, sssHD presents limited differences between performing and not performing re-balance preprocessing. CONCLUSIONS: sssHD is a practical feature selection method for high-dimensional class-imbalanced data, which is simple and can be an alternative for performing feature selection in class-imbalanced data. sssHD can be easily extended by connecting it with different re-balance preprocessing, different sparse regularization structures as well as different classifiers. As such, the algorithm is extremely general and has a wide range of applicability.

When altruists cannot help: the influence of altruism on the mental health of university students during the COVID-19 pandemic.

BACKGROUND: The positive predictive effect of altruism on physical and psychological well-being has been extensively demonstrated in previous studies, but few studies have examined the effect of altruism on negative mental health outcomes when altruists cannot perform altruistic behaviours. This study explored the influence of altruism on negative affect and mental health (anxiety and depressive symptoms) during the COVID-19 pandemic while people self-isolated at home in China. METHOD: University students were recruited to participate in a cross-sectional online survey during the outbreak of COVID-19 in China. Self-reported perceived risk, altruism, negative affect, anxiety and depressive symptoms were measured using the Self-Report Altruism Scale (SRA scale), the Positive and Negative Affect Schedule (PANAS), the 7-item Generalized Anxiety Disorder Scale (GAD-7) and the 9-item Patient Health Questionnaire depression scale (PHQ-9). A structural equation model was used to analyse the mediating and moderating effects on mental health. RESULTS: The final sample comprised 1346 Chinese participants (Mage = 19.76 ± 2.23 years, 73% female). Overall, the higher the risk the participants perceived, the more negative affect they exhibited (ß = 0.16, p < .001), and thus, the more anxious and depressed they felt (ß = 0.134, p < .001); however, this relationship between risk perception and negative affect was moderated by altruism. In contrast to previous studies, the increase in negative affect associated with the increased perceived risk was pronounced among individuals with high altruism (t = 7.68, p < .001). CONCLUSIONS: Individuals with high altruism exhibited more negative affect than those with low altruism, which indirectly increased their anxiety and depressive symptoms. These findings enrich theories of altruism and provide valuable insight into the influence of altruism on mental health during the COVID-19 outbreak.