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Simple Summary: Two subspecies of largemouth bass (Micropterus salmoides, LMB) with different thermal tolerance, northern largemouth bass (NLMB) and Florida largemouth bass (FLMB), were subjected to acute and chronic thermal stress at 33 °C. Then, variations of 12 candidate biomarkers between NLMB and FLMB were analyzed. Compared to NLMB, FLMB exhibited a lower plasma cortisol level and a higher expression of hsp90 under acute thermal stress. Additionally, lower expression of hsp70 in FLMB was observed under chronic thermal stress. The differences in plasma cortisol levels and hsp expression represent variations in thermal tolerance between the two subspecies of LMB, providing valuable information for the identification and breeding of LMB varieties with better thermal tolerance in the future. Affected by the continuously rising temperature, thermal stress leads to a delinked growth rate and resistance to stress in cultured largemouth bass (Micropterus salmoides, LMB) in China. Identification of LMB with better thermal resistance will benefit the breeding of new varieties. However, there has been limited reporting on the evaluation to identify LMB with better thermal resistance. LMB consists of the northern LMB (Micropterus salmoides salmoides, NLMB) and the Florida LMB (Micropterus salmoides floridanus, FLMB). Due to their different geographical distributions, it has been suggested that FLMB exhibit better thermal resistance compared to NLMB. In this study, NLMB and FLMB were subjected to thermal stress for 3 h (acute) and 60 d (chronic) at 33 °C, respectively. Subsequently, the variations of 12 candidate biomarkers between NLMB and FLMB were analyzed. Exposure to acute thermal stress significantly increased plasma cortisol, blood glucose, and lactate levels; activities of superoxide dismutase (SOD), glutathione peroxidase (GPX), catalase (CAT), glucose kinase (GK), pyruvate kinase (PK), lactate dehydrogenase (LDH), and glucose 6 phosphatase (G6Pase); and the expressions of hsp70 and hsp90 in both NLMB and FLMB (p < 0.05). Compared to NLMB, FLMB exhibited a lower plasma cortisol level and a higher expression of hsp90 under acute thermal stress (p < 0.05). Exposure to chronic thermal stress significantly increased plasma cortisol and blood glucose levels, as well as activities of GK, PK, LDH, and G6Pase, as well as expressions of hsp70 and hsp90 in both NLMB and FLMB (p < 0.05). Additionally, FLMB showed a lower expression of hsp70 compared to NLMB (p < 0.05). In conclusion, our results showed that LMB with lower plasma cortisol level and higher expression of hsp90 under acute thermal stress, as well as lower expression of hsp70 under chronic thermal stress were suggested to have better thermal resistance. Our study provides valuable information for identifying and breeding LMB varieties with better thermal resistance in the future. [ABSTRACT FROM AUTHOR]

Microbial nitrate reduction can be driven by organic carbon oxidation, as well as by inorganic electron donors, such as reduced forms of sulfur and iron. An apparent inverse oxygen isotope fractionation effect was observed during nitrate reduction in sediment incubations from five sampling sites of a freshwater lake, Hongze Lake, China. Incubations with organic and inorganic electron donor additions were performed. Especially, the inverse oxygen isotope effect was intensified after glucose addition, whereas the incubations with sulfide and Fe2+ showed normal fractionation factors. Nitrate reductase encoding genes, napA and narG, were analysed with metagenomics. Higher napA/narG ratios were associated with higher oxygen fractionation factors. The most abundant clade (59%) of NapA in the incubation with glucose was affiliated with Rhodocyclales. In contrast, it only accounted for 8%–9% of NapA in the incubations with sulfide and Fe2+. Differences in nitrate reductases might explain different oxygen isotope effects. Our findings also suggested that large variance of O‐nitrate isotope fractionations might have to be considered in the interpretation of natural isotope records. [ABSTRACT FROM AUTHOR]

The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) viruses is mainly transmitted through respiratory droplets. Notably, some coronavirus disease 2019 (COVID-19) patients have ocular manifestations, including conjunctival hyperaemia, chemosis, epiphora, and increased secretions. However, the association between SARS-CoV-2 and ocular surface diseases is poorly described. Between May 2020 and March 2021, a total of 2, 0157 participants from six districts of China were enrolled. Serum samples were tested for immunoglobulin G and M (IgG and IgM) antibodies against the SARS-CoV-2 spike protein and nucleoprotein using magnetic chemiluminescence enzyme immunoassays. Throat swabs were tested for SARS-CoV-2 RNA using RT-PCR assays in a designated virology laboratory. Fisher exact, χ2 test, and logistic regression analysis were performed. Of 2, 0157 serum samples tested, 1, 755 (8.71%) were from ocular surface diseases, 1, 2550 (62.26%) from no-ocular surface diseases (ocular diseases except ocular surface diseases), 5, 852 (29.03%) from no-ocular diseases. SARS-CoV-2 prevalence for the combined measure was 0.90% (182/2, 0157). Seroprevalence of SARS-CoV-2 was significantly (p<0.05) higher in the population with ocular surface diseases (2.28%, 40/1755) compared with no-ocular surface diseases (0.70%, 88/1, 2550), and no-ocular diseases (0.92%, 54/5, 852). Similar results were also observed with respect to sex, age, time, and districts. Logistic regression analyses revealed that ocular surface diseases [ocular surface diseases vs. no-ocular diseases (p=0.001, OR =1.467, 95% CI=1.174-1.834); ocular surface diseases vs. no-ocular surface diseases (p<0.001, OR =2.170, 95% CI=1.434-3.284)] were associated with increased risk of susceptible to SARS-CoV-2 infection. In a word, there was a significant association between ocular surface disease and SARS-CoV-2 infection. Therefore, increasing awareness of eye protection during the pandemic is necessary, especially for individuals with ocular surface diseases. [ABSTRACT FROM AUTHOR]

Yucha is a home-made, fermented fish product in South China. The quality of yucha can vary depending on environmental factors. In order to determine the effects of temperature on bacterial biodiversity and quality of fermented yucha products, in the present study, yucha was fermented at 15°C, 20°C, 25°C, and 30°C. Bacterial cells in all yucha samples grew from 3.7 log CFU/g at the onset of the fermentation and reached growth over 7.0 log CFU/g within 1 week. Lactobacillus plantarum was predominated in the 20°C and 25°C fermented yucha products, while Lactobacillus sakei and Lactobacillus brevis were the most abundant in the yucha products fermented at 15°C and 30°C, respectively. Predominant bacterial species are presumed to be potential starters to drive yucha fermentation. Evaluation of yucha qualities demonstrated that lower biogenic amine contents, better texture properties, and more desirable volatile compounds were identified in yucha products fermented at 20°C. Therefore, this temperature is recommended for industrial yucha processing in the future. [ABSTRACT FROM AUTHOR]

The largemouth bass is an important species, and its culture has risen sharply with the surge in fish aquaculture in China. Due to the lack of selective breeding technology for the largemouth bass, the growth rate and disease resistance are low, its sexual maturation is slow, and other serious problems are contributing to a sharp decline in the safety and quality of largemouth bass products in recent decades. Therefore, comprehensive breeding programs to improve the economic performance and promote the modern industrial development of largemouth bass must be considered a priority. Here, a total of 152 adult largemouth bass, including two parents and 150 progenies, were selected to produce the genetic mapping family. Then, a high-density linkage map was constructed based on restriction site–associated DNA sequencing using 6,917 single-nucleotide polymorphisms (SNPs) located in 24 linkage groups (LGs). The total genetic length of the linkage map was 1,261.96 cM, and the length of each LG varied from 24.72 cM for LG02 to 117.53 cM for LG16, with an average length of 52.58 cM and an average SNP number of 286. Thirteen significant quantitative trait loci (QTLs) for sex determination were located on LG04, LG05, LG08, LG12, LG15, LG21, and LG23. An informative QTL cluster that included six QTLs was detected on LG12. However, one notable QTL, which accounted for 71.48% of the total phenotypic variation, was located in the region of 1.85 cM on LG05. In addition, 32 identified QTLs were related to growth, including body weight, body length, body height, and head length. The QTLs for these growth-related traits are located in 13 LG regions and have little effect on phenotypic variation. This high-density genetic linkage map will enable the fine-mapping of economic traits and support the future genome assembly of the largemouth bass. Additionally, our study will be useful for future selective culture of largemouth bass and could potentially be used in molecular-assisted breeding of largemouth bass for aquaculture. [ABSTRACT FROM AUTHOR]

Purpose: It has been hypothesised that uric acid (UA) has a protective effect against oxidative damage in the central nervous system. Therefore, we investigated serum UA concentrations in patients with primary open‐angle glaucoma (POAG) and explored the relationship between serum UA concentration and glaucoma severity. Methods: This prospective, cross‐sectional, case–control study was conducted in 163 POAG patients and 103 normal controls. Clinical and demographic information was obtained from the medical data platform of the Eye & ENT Hospital of Fudan University, Shanghai, China. The POAG patients were categorised into mild [median deviation (MD) ≤ 6.00 dB], moderate (MD > 6 Db–≥12 dB) and severe (MD > 12 dB) subgroups, based on their visual field MD results. Results: The level of serum UA in the POAG group (0.321 ± 0.084 mmol/l) was approximately 12.77% lower (p < 0.001) than that of the control group (0.362 ± 0.053 mmol/l). The UA/creatinine (Cr) ratio was approximately 14.99% lower (p < 0.001) in patients with POAG (4.47 ± 1.15), compared with the control group (5.14 ± 1.05). The mean level of UA was lowest in the severe POAG group, followed by the moderate POAG group, and the mild POAG group (p < 0.001). A similar trend was observed when UA levels were compared between the POAG and control groups in males. Multivariate regression analyses showed a significant negative correlation between UA and vertical cup–disc ratio (B = −0.320, p = 0.034), and UA and MD (B = −0.441, p = 0.031) in males. Conclusion: Primary open‐angle glaucoma patients have lower UA levels; however, a negative association between UA levels and disease severity was evident in male patients. [ABSTRACT FROM AUTHOR]

Purpose: Retinal vein occlusion (RVO) and diabetic retinopathy (DR) are two major sight-threatening diseases which may lead to neovascular glaucoma (NVG). The aim of this study was to explore the association between platelet parameters and NVG. Methods: A total of 185 subjects were enrolled for the study from January, 2012 to December, 2015 at the Eye-ENT Hospital of Fudan University. Patients include those with NVG secondary to RVO (RVO group, n = 38), patients with NVG secondary to DR (DR group, n = 47), diabetics mellitus without retinopathy (DM group, n = 52), and healthy individuals (control group, n = 48). A complete ophthalmological examination including visual field examination, A-scan ultrasound, Fundus photography, and measurement of platelet parameters were performed for NVG subjects. Results: There was no statistical difference in the mean age and gender among the RVO, DR, and control groups (p>0.05). The mean level of platelet distribution width (PDW) was higher (p<0.001) in the RVO group (15.16±2.13fl) and DR group (16.17±1.66fl) when compared with the control group (13.77±2.99fl). The mean plateletcrit (PCT) value of the RVO group (0.229±0.063%) was also higher (p = 0.049) than the control group (0.199±0.045). In the DR group, mean platelet volume (MPV) value (10.72±1.57fl) was significantly higher (p = 0.002) than the control group (9.75±0.89fl). A similar trend was observed when platelet parameters were compared among the 3 groups with respect to age. The mean level of PDW was significantly higher (p<0.001) in the DR group (16.17±1.66fl) compared with the DM group (13.80±3.32fl). Stepwise multiple logistic regression analysis revealed that PDW (OR = 1.44, 95%CI = 1.149–1.805, p = 0.002) and MPV (OR = 1.503, 95%CI = 1.031–2.192, p = 0.034) were associated with the DR group, PDW (OR = 1.207, 95%CI = 1.010–1.443, p = 0.039) and PCT (OR = 1.663, 95%CI = 1.870–2.654, p = 0.036) were associated with the RVO group. Conclusion: Our results suggest that increased PDW and MPV are associated with the NVG secondary to DR group, elevated PDW and PCT are associated with the RVO group. It indicates that platelets might be an important factor in the onset and/or development of NVG. [ABSTRACT FROM AUTHOR]

BACKGROUND Probiotics are widely used in the food industry and medicine fields in China, but few studies have been conducted to evaluate the actual microbial amounts and species in probiotic products, which may conflict with the labels and mislead consumers to choose inappropriate foods or medicines. RESULTS Twenty commercial dairy products and eight commercial 'healthcare' samples were collected from markets in China and tested using culture-dependent and culture-independent methods. The results suggested that the total bacterial counts of most commercial products met the minimum quantitative requirement of the Chinese national standard (6.00 log colony-forming units g−1). However, the bacterial counts of specific species were inconsistent with the labelling. In parallel, denaturing gradient gel electrophoresis analysis indicated that some probiotic-containing products were wrongly labelled; no Bifidobacterium species were detected in the products claiming to contain bifidobacteria, and the probiotic characteristics (antimicrobial activity, acid resistance and bile resistance) of some isolates had degraded. Moreover, some contaminating bacteria, e.g. Enterobacter sp., Klebsiella sp. and Serratia sp., were also detected in these products. CONCLUSION The combination of culture-dependent and culture-independent methods was proven to quickly and conveniently detect the microbial diversity in probiotic products, and more effort is required to regulate the probiotic market in China. © 2013 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

Abstract: During June through October 2008, numerous cultured largemouth bass (Micropterus salmoides) died in the Foshan area of Guangdong Province, China. Affected fish had ulcerations on the skin and muscle. Epithelioma papillosum cyprini (EPC) cell cultures inoculated with filtrates of muscle homogenates from the diseased fish developed the cytopathic effect (CPE) 5days after inoculation at the primary passage. Transmission electron microscopy of the ulcerative muscle tissue and the infected EPC cells revealed a cytoplasmic, icosahedral virion that averaged 145nm in diameter. Intramuscular injection of the virus (≥107.82 TCID50 ml−1) resulted in clinical signs of the disease and caused 100% mortality of healthy largemouth bass. In addition, the mandarinfish (Siniperca chuatsi) was susceptible to the virus after intramuscular injection of the virus (0.2ml of 109.82 TCID50 ml−1), and the mortality was 20%. However, no death or clinical signs were found in grass carp (Ctenopharyngodon idella), bighead carp (Aristichthys nobilis), Nile tilapia (Oreochromis niloticus), crucian carp (Carassius carassius), common carp (Cyprinus carpio), and fancy carp (C. carpio) after experimental infection. DNA fragments of the viral major capsid protein (MCP) and DNA methyltransferase (MTase) were amplified and sequenced. Subsequent multiple alignment and phylogenetic analysis revealed that the virus is identical to doctor fish virus (DFV) and closely related to largemouth bass virus (LMBV). [Copyright &y& Elsevier]

Chouguiyu (stinky Mandarin fish), a traditional spontaneously fermented fish in China, is famous for its unique aroma and pleasant taste. However, the relationships between the succession of microorganisms during the fermentation and the formation of Chouguiyu 's unique aroma and taste remain to be characterized. In this study, 16S rRNA gene amplicon sequencing was done to investigate the evolving microbiota during Chouguiyu fermentation, and the volatile compounds and amino acids profiles were measured alongside with chemical characterization of the samples (e.g., determination of pH, TVB-N, TBARS, and TCA-soluble peptides). Based on the changes of the microbiota, the fermentation was categorized into two stages: early-fermentation, 1st-3rd days; and late-fermentation, 4th-7th days. Linalool, piperitone, anethole, 1-octen-3-ol, 2-methyl-3-octanone and indole were identified as characteristic volatile compounds in Chouguiyu. According to the sensory evaluation results, the flavor of the Chouguiyu was reinforced in the late-fermentation stage. Redundancy analysis showed the relationships between evolving microbiota and the formation of Chouguiyu 's aroma and taste, and Psychrilyobacter was identified to be the most important bacterial genus contributing to flavor and aroma development, followed by Fusobacterium , Arcobacter and O c eanisphaera. These genera were positively correlated with Glu, Met, Tyr, Pro, linalool, piperitone, indole, TBARS, TVB-N, and TCA, and influenced the flavor and aroma of the Chouguiyu. The results of this study provided a scientific basis to further improve Chouguiyu production. • Chouguiyu 's fermentation process was divided into early-fermentation and late-fermentation. • The changes of features in Chouguiyu were more pronounced during the late-fermentation stage. • Four genera were found to be highly related to the change of Chouguiyu' s flavor and aroma. • These 4 genera included Psychrilyobacter , Fusobacterium , Arcobacter and Oceanisphaera. • The Psychrilyobacter was highly related to the flavor and aroma of Chouguiyu. [ABSTRACT FROM AUTHOR]

Myofibrillar protein (MFP) of Japanese seerfish (JS) was oxidized by Fenton system (1, 4, 8, 16 mM H2O2 for 0, 2, 4, 6 hr). After oxidation, α‐helix ratio and sulfhydryl content of MFP declined along with the increased carbonyl and dityrosine levels. Bromophenol blue bound in MFP under 1 mM H2O2 slightly increased. Polymers together with attenuated myosin heavy chain in protein pattern were observed. Compared with non‐oxidized MFP, storage modulus (G′) of MFP subjected to 1 mM H2O2 for 4 hr increased while that of MFP exposed to 16 mM H2O2 declined. When treated with microbial transglutaminase (MTG), mildly oxidized (1 mM H2O2, 2 hr) MFP showed higher G′ while heavily oxidized (16 mM H2O2, 2 hr) MFP had lower G′ than control. Oxidation showed pronounced influences on physiochemical and gelling properties of JS MFP and the oxidation extent affected MTG role on it. Practical applications: Protein oxidation occurs extensively in muscle and exerts great influences on muscle food quality. JS is widely used for producing gel food in China. Its muscle also contains oxidation initiators such as H2O2, hemoglobin and lipids, increasing the susceptibility to protein oxidation. Results of the study exposed the effects of hydroxyl radical oxidation on physiochemical and gelling properties of JS MFP. It provides strategic support to improve gel properties of MFP by manipulating oxidation. [ABSTRACT FROM AUTHOR]

Sex dimorphism of economic traits such as growth rate and body size have potential breeding value in aquaculture. Largemouth bass (Micropterus salmoides L.) is an important freshwater cultured fish in China and the females live longer and reach larger sizes than males. However, the lacking of sex-specific makers and the unclear sex determination mechanism inhibits the development of all-female breeding. In this study, 5 females and 5 males were randomly selected and sequenced with whole-genome re-sequencing technology. In total, 1394 filtered SNPs and 425 filtered InDels were finally identified, and most of these makers were located at Chr7 and Chr18. The validation of the 35 SNPs located at Chr7 in three distinct population (n = 72) indicated that 2 SNPs (S4 and S6) could distinguish the females and males with 100% accuracies, which were genotyped as CC and CG, AA and AT in the females and males, respectively. Further, 10 and 6 InDels with sizes more than 18 bp were finally screened out on Chr7 and Chr18. 2 male-specific InDels (rs3394676 and rs3496814) located at Chr7 could effectively distinguish the above females and males with a PCR-based agarose gel electrophoresis, which performed as one band in the females and two bands in the males, respectively. These results suggested the Chr7 might be the sex chromosome and a XX/XY sex determination system in largemouth bass. In conclusion, a whole-genome re-sequencing method was first conducted to provide usefulness sex-specific makers and a XX/XY sex determination system in largemouth bass, which contributes to study of the sex determination mechanisms and the development of mono-sex population breeding. • Whole-genome re-sequencing were first conducted to explore the genetic differences between males and females in largemouth bass. • Two male-specific SNPs and two male-specific InDels were developed to distinguish genetic sex of largemouth bass. • The chromosome 7 was the sex chromosome in largemouth bass. • The sex determination system was a XX/XY determination system in largemouth bass. [ABSTRACT FROM AUTHOR]

Little is known about the relationship between physicochemical characteristics and bacterial community of sour meat, a traditional fermented meat product in China. In this study, temperature effects on bacterial community and quality of sour meats during fermentation were investigated. The results showed the reduction of pH, TBARS, and water content was closely related to the increase in temperature. Microbial succession, in which the dominant microorganism species found in the microbial community changes, was observed during the fermentation process of sour meat. The dominant species found in the early stages of fermentation was Lactobacillus sakei whereas the dominant species was Lactobacillus curvatus during the middle stage and Lactobacillus plantarum during the later stage. Higher temperatures were found to be related to the shift of water populations T 2 (including T 2b1 , T 2b2 , T 21 , and T 22) toward faster relaxation times. Rapid fermentation and better quality were obtained at higher fermentation temperatures (particularly at 25 °C), which might be due to increased inhibition of Enterobacteriaceae and Pseudomonas growth as well as tougher texture. Redundancy analysis (RDA) showed a close relationship between L. plantarum and desired product characteristics, which indicated that L. plantarum could be regarded as an indicator of fermentation maturation and product quality. Image 1 • Better quality sour meats are produced when fermented at 25 °C. • L. sakei , L. curvatu s, and L. plantarum became the dominant species successively. • L. plantarum may be a potential indicator of fermentation maturity and good quality. [ABSTRACT FROM AUTHOR]

Suancai is a popular fermented product of Brassica vegetable in China. As important additive, salt concentration has crucial effects on the quality of suancai. To investigate the effects of salt concentration on suancai fermentation, the microbial diversity and volatile compounds (VCs) during fermentation were investigated by using Illumina HiSeq sequencing and GC-MS. Firmicutes, Proteobacteria and Ascomycota were detected as the main phylum during the fermentation with different salt concentrations. Lactobacillus , Lactococcus , Klebsiella , Weissella , Pediococcus , Candida , Cladosporium , Gibberella , Aspergillus , etc., were detected were observed during the fermentation with different concentrations. After fermentation, Lactobacillus predominated the fermentation of suancai and was not affected by salt concentration. Pediococcus , Leuconostoc , Weissella , Sporobolomyces , Azospirillum , Klebsiella , Acinetobacter and Cladosporium were significant affected by salt concentration. Salt addition could affect the VCs profiles and reduce the isothiocyanates after fermentation. Seventy-nine VCs were detected and strongly correlated with the dominant genus Lactobacillus during suancai fermentation. The inoculated fermentation of Lactobacillus could improve the VCs during fermentation. In conclusion, 6% salt addition could acquire a higher Lactobacillus abundance and a better taste quality. These results may facilitate the understanding of the effect of salt concentration on the fermentation ecology to improve suancai characteristics. • The 6% (w/w) salt addition was the best for suancai fermentation and quality. • Lactobacillus and unclassified fungus were dominant genera in suancai. • Seventy-nine VCs were detected during suancai fermentation with different salinity. • VCs were strongly correlated with Lactobacillus during suancai fermentation. • The inoculation of L. plantarum increased the VCs during suancai fermentation. [ABSTRACT FROM AUTHOR]

The bacterial diversity and volatile flavor compounds (VFCs) during suancai fermentation in different temperatures were investigated by Illumina Hiseq sequencing and GC-MS. Firmicutes and Proteobacteria were observed to be the dominant phyla during the fermentation. Lactobacillus , Serratia , Leuconostoc , Pseudomonas , Pseudomonas , Pediococcus , etc., were observed as the main genus. Serratia and Pseudomonas predominated the early stage of suancai fermentation, while Lactobacillus predominated the later stage. Leuconostoc predominated the fermentation at 10 °C and 15 °C, while Weissella and Lactococcus predominated at 20 °C and 25 °C. A total of 86 VFCs were detected in all suancai samples. With the increase of the fermentation temperature, the kinds of VFCs were also increased. Lactobacillus , Pediococcus , Lactococcus , Brochothrix , Psychrobacter , Pseudoalteromonas , Acinetobacter and Enterobacter were the important bacteria related to VFCs during the fermentation. The bacteria were highly correlated with the VFCs in suancai fermentation. As the most dominant genus, Lactobacillus was significantly positive correlated with 13 VFCs. The correlation between the bacteria and VFCs in suancai could be used to search for microbial markers. In conclusion, 20 °C could accelerate the maturation and improve the sensory quality of suancai. This study could provide useful guidelines for screening of strains that contribute to the flavor formation in suancai fermentation. • Firmicutes and Proteobacteria were observed as dominant phylum in suancai. • Lactobacillus predominated the later stage of the suancai fermentation. • The biomarkers in suancai fermented under different temperature were different. • Eight important genera were significant correlated with the VFCs in suancai. • Lactobacillus was significant positive correlated with 13 VFCs in suancai. [ABSTRACT FROM AUTHOR]

This study was designed to explore the temperature effects on bacterial communities and metabolites, as well as their relationships during the fermentation of sour meat, a traditional fermented meat product in the ethnic minority regions of China. Results showed that reduction of pH and increase of lactic acid and free amino acid contents occurred (p < 0.05) as the fermentation temperature and time increased, and the tendency was more apparent at higher temperature. During the fermentation, Lactobacillus gradually replaced other genera, and higher the temperature, more rapid was the process. Both the number and amount of volatile organic compounds increased at higher temperatures. Hexanal, benzaldehyde, nonanal, (E,E)-2,4-decadienal, 1-octen-3-ol and octanal were identified as the key volatile organic compounds produced by Lactobacillus in sour meat as main contributors to odor as confirmed by variable importance in the projection analysis. Redundancy analysis and Pearson correlation showed positive correlation between Lactobacillus and desired product characteristics, such as higher content of lactic acid, free amino acids, volatile organic compounds, and lower pH and water activity values, which may represent a better quality and longer shelf life after fermentation at higher temperature. Therefore fermentation at 20 °C and 25 °C are proposed as optimum temperatures for sour meat production. • Faster fermentation process of sour meat were obtained at higher temperatures (20 °C and 25 °C). • There were more abundant metabolites in batches of higher fermentation temperatures. • Lactobacillus was the dominant genus eventually. • Lactobacillus was positively related to the desirable quality and flavor of sour meat. [ABSTRACT FROM AUTHOR]

Background: Pseudomonas juntendi is a newly identified opportunistic pathogen, of which we have limited understanding. P. juntendi strains are often multidrug resistant, which complicates clinical management of infection., Methods: A strain of Pseudomonas juntendi (strain L4326) isolated from feces was characterized by MALDI-TOF-MS and Average Nucleotide Identity BLAST. This strain was further subject to whole-genome sequencing and Maximum Likelihood phylogenetic analysis. The strain was phenotypically characterized by antimicrobial susceptibility testing and conjugation assays., Results: We have isolated the novel P. juntendi strain L4236, which was multidrug resistant, but retained sensitivity to amikacin. L4236 harbored a megaplasmid that encoded bla OXA-1 and a novel bla IMP-1 resistance gene variant. P. juntendi strain L4236 was phylogenetically related to P. juntendi strain SAMN30525517., Conclusion: A rare P. juntendi strain was isolated from human feces in southern China with a megaplasmid coharboring bla IMP-1-like and bla OXA-1 . Antimicrobial selection pressures may have driven acquisition of drug-resistance gene mutations and carriage of the megaplasmid., (© 2024. The Author(s).)

Rivers play a significant role in the global nitrous oxide (N 2 O) budget. However, the microbial sources and sinks of N 2 O in river systems are not well understood or quantified, resulting in the prolonged neglect of nitrification. This study investigated the isotopic signatures of N 2 O, thereby quantifying the microbial source of N 2 O production and the degree of N 2 O reduction in the Yellow River. Although denitrification has long been considered to be the dominant pathway of N 2 O production in rivers, our findings indicated that denitrification only accounted for 18.3% (8.2%-43.0%) of the total contribution to N 2 O production in the Yellow River, with 50.2%-80.2% being concurrently reduced. The denitrification contribution to N 2 O production (R 2  = 0.44, p < 0.01) and N 2 O reduction degree (R 2  = 0.70, p < 0.01) were positively related to the dissolved organic carbon (DOC) content. Similar to urban rivers and eutrophic lakes, denitrification was the primary process responsible for N 2 O production (43.0%) in certain reaches with high organic content (DOC = 5.29 mg/L). Nevertheless, the denitrification activity was generally constrained by the availability of electron donors (average DOC = 2.51 mg/L) throughout the Yellow River basin. Consequently, nitrification emerged as the primary contributor in the well-oxygenated Yellow River. Additionally, our findings further distinguished the respective contribution of ammonia-oxidizing bacteria (AOB) and archaea (AOA) to N 2 O emissions. Although AOB dominated the N 2 O production in the Yellow River, the AOA specie abundance (AOA/(AOA + AOB)) contributed up to 32.6%, which resulted in 25.6% of the total nitrifier-produced N 2 O, suggesting a significant occurrence of AOA in the oligotrophic Yellow River. Overall, this study provided a non-invasive approach for quantifying the microbial sources and sinks to N 2 O emissions, and demonstrated the substantial role of nitrification in the large oligotrophic rivers., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

Background: Primary angle closure glaucoma (PACG) is the leading cause of irreversible blindness in Asia, and no reliable, effective diagnostic, and predictive biomarkers are used in clinical routines. A growing body of evidence shows metabolic alterations in patients with glaucoma. We aimed to develop and validate potential metabolite biomarkers to diagnose and predict the visual field progression of PACG., Methods: Here, we used a five-phase (discovery phase, validation phase 1, validation phase 2, supplementary phase, and cohort phase) multicenter (EENT hospital, Shanghai Xuhui Central Hospital), cross-sectional, prospective cohort study designed to perform widely targeted metabolomics and chemiluminescence immunoassay to determine candidate biomarkers. Five machine learning (random forest, support vector machine, lasso, K-nearest neighbor, and GaussianNaive Bayes [NB]) approaches were used to identify an optimal algorithm. The discrimination ability was evaluated using the area under the receiver operating characteristic curve (AUC). Calibration was assessed by Hosmer-Lemeshow tests and calibration plots., Results: Studied serum samples were collected from 616 participants, and 1464 metabolites were identified. Machine learning algorithm determines that androstenedione exhibited excellent discrimination and acceptable calibration in discriminating PACG across the discovery phase (discovery set 1, AUCs=1.0 [95% CI, 1.00-1.00]; discovery set 2, AUCs = 0.85 [95% CI, 0.80-0.90]) and validation phases (internal validation, AUCs = 0.86 [95% CI, 0.81-0.91]; external validation, AUCs = 0.87 [95% CI, 0.80-0.95]). Androstenedione also exhibited a higher AUC (0.92-0.98) to discriminate the severity of PACG. In the supplemental phase, serum androstenedione levels were consistent with those in aqueous humor (r=0.82, p=0.038) and significantly (p=0.021) decreased after treatment. Further, cohort phase demonstrates that higher baseline androstenedione levels (hazard ratio = 2.71 [95% CI: 1.199-6.104], p=0.017) were associated with faster visual field progression., Conclusions: Our study identifies serum androstenedione as a potential biomarker for diagnosing PACG and indicating visual field progression., Funding: This work was supported by Youth Medical Talents - Clinical Laboratory Practitioner Program (2022-65), the National Natural Science Foundation of China (82302582), Shanghai Municipal Health Commission Project (20224Y0317), and Higher Education Industry-Academic-Research Innovation Fund of China (2023JQ006)., Competing Interests: SL, JR, ZJ, YQ, MS, YL, JW, YS, XS, SG, WC No competing interests declared, (© 2023, Li, Ren, Jiang et al.)

Candida parapsilosis is becoming a predominant non- albicans cause of invasive candidiasis (IC). Echinocandins are the preferred choice for IC treatment and prophylaxis. Resistance to echinocandins in C. parapsilosis has emerged in several countries, but little is known about the susceptibility profile in China or about mechanisms of resistance. Here, we investigated the echinocandin susceptibilities of 2523 C. parapsilosis isolates collected from China and further explored the resistance mechanism among echinocandin-resistant isolates. Anidulafungin exhibited the highest MICs (MIC 50/90 , 1 and 2 µg/mL; GM, 0.948 µg/mL), while caspofungin showed better activity (0.5 and 1 µg/mL; 0.498 µg/mL). Significantly higher echinocandin MICs were observed among blood-derived isolates compared to others, especially for caspofungin (GM, 1.348 µg/mL vs 0.478 µg/mL). Isolates from ICU and surgical wards also showed higher MICs. Twenty isolates showed intermediate phenotypes for at least one echinocandin. One was resistant to all three echinocandins, fluconazole and voriconazole, which caused breakthrough IC during long-term exposure to micafungin. WGS revealed this isolate carried a mutation S656P in hotspot1 region of Fks1. Bioinformatics analyses suggested that this mutation might lead to an altered protein conformation. CRISPR Cas9-mediated introduction of this mutation into a susceptible reference C. parapsilosis strain increased MICs of all echinocandins 64-fold, with similar results found in the subspecies, C. orthopsilosis and C. metapsilosis . This is the first report of a multi-azole resistant and pan-echinocandin resistant C. parapsilosis isolate, and the identification of a FKS1 S656P conferring pan-echinocandin resistance. Our study underscores the necessity of rigorous management of antifungal use and of monitoring for antifungal susceptibility.

In this study, the spatial and seasonal bacterioplankton community dynamics were investigated in the main channel of the Middle Route of the South-to-North Water Diversion Project (MRP) using Illumina HiSeq sequencing. Water samples were collected in spring and summer from south to north at eight water quality monitoring stations, respectively. The results showed that seasonal changes had a more pronounced effect on the bacterioplankton community compositions (BCCs) than spatial variation. The diversity analysis results indicated that samples of summer have more operational taxonomic units (OTUs), higher richness and diversity than those in spring. The main phyla, Proteobacteria, Actinobacteria, Bacteroidetes, Cyanobacteria and Chloroflexi, displayed significant differences (P < 0.05) between spring and summer in the main channel. The Redundancy analysis (RDA) targeting all samples indicated that specific conductivity (SPC), dissolved oxygen (DO), pH and temperature (T) might be key factors in driving BCCs, while trophic status showed no significant correlation (P > 0.05). The present study provides important insights into the potential ecological roles of specific taxa in the new artificial ecosystem and it offers reference for studies on ecosystem succession of other giant interbasin water diversion project in the world., (Copyright © 2018 Institut Pasteur. Published by Elsevier Masson SAS. All rights reserved.)

Objective: Obesity and a high-fat diet have been found to be associated with an increased risk of age-related cataract (ARC). Thus, this study aimed to investigate whether serum lipid levels are associated with the incidence of ARC., Design: Cross-sectional, case-control study., Setting: EyeandENT Hospital of Fudan University, Shanghai, China., Participants: A total of 219 ARC (male=94, female=125) subjects and 218 (male=110, female=118) normal control subjects were recruited in this study., Outcome Measures: A detailed eye and systematic examination was performed. Serum high-density lipoprotein cholesterol (HDL-C), low-density lipoprotein cholesterol (LDL-C), triglyceride (TG) and cholesterol (CHO) levels were measured by enzymatic colorimetry, and serum apolipoprotein A (APOA) and apoB (APOB) levels were measured by immunoturbidimetry. The subgroups were classified according to gender and types of disease (cortical, nuclear and posterior subcapsular cataract). Logistic regression analyses were performed to identify the association between serum lipid levels and ARC., Results: The serum LDL-C, TG, CHO and APOA levels were significantly higher (p<0.05) in the ARC group than in the control group. A similar result was observed when the serum lipid concentrations were compared between the ARC and control groups both in male and female subgroups. A higher proportion of individuals in the ARC group had higher LDL-C, TG, CHO and APOA levels (fold=3.45, 17.37, 3.27 and11.91, respectively; p<0.0001 in all cases) than in the control group. Results of the logistic regression analyses revealed that high LDL-C (ORs=1.897, 95% CI 0.960 to 3.678) and TG (OR=1.854, 95% CI 1.232 to 2.791) were the independent risk factors for ARC., Conclusion: The serum LDL-C and TG levels were demonstrated to be independent risk factors for ARC., Competing Interests: Competing interests: None declared., (© Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2018. All rights reserved. No commercial use is permitted unless otherwise expressly granted.)

In April 2011, 40% mortality of Largemouth Bass Micropterus salmoides juveniles occurred at a farm of Zhongshan City, Guangdong Province, China. Infected fish became lethargic, exhibited corkscrew and irregular swimming, and developed a distended abdomen and crooked body. Fish began to die within 2 d after the appearance of clinical signs. In order to analyze the pathogeny and diagnose the disease earlier, observation of clinical signs, cell infection, titer calculation, electron microscopy, immersion infection assay for fish, and nucleotide sequence analysis were carried out. Fathead minnow (FHM) cell cultures, inoculated with filtrate of liver and spleen homogenates from the diseased fish, developed the obvious cytopathic effect 46 h after inoculation in the primary culture and 24 h at the first passage. Typical rhabdovirus particles, 115-143 nm in length and 62-78 nm in diameter, were observed in infected FHM cells by direct transmission electron microscopy. The isolated virus produced a titer of 10(7.15) TCID50/mL. Immersion-Fish infected with the virus had similar clinical signs and 80% mortality with 10(2.5) LD50/mL. The data indicated that the rhabdovirus was the lethal pathogeny of the current disease. Based on nucleoprotein-gene nucleotide sequence multiple alignment analysis, the newly isolated virus is a strain of Siniperca chuatsi rhabdovirus (SCRV) under family Rhabdoviridae, which was initially isolated from Mandarin Fish Siniperca chuatsi. Up to the present, at least four virus strains have been isolated from diseased Largemouth Bass, which have had different clinical signs. Comparison of the clinical signs can help in an early diagnosis of the disease.