Gut microbiota-brain bile acid axis orchestrates aging-related neuroinflammation and behavior impairment in mice.

Emerging evidence shows that disrupted gut microbiota-bile acid (BA) axis is critically involved in the development of neurodegenerative diseases. However, the alterations in spatial distribution of BAs among different brain regions that command important functions during aging and their exact roles in aging-related neurodegenerative diseases are poorly understood. Here, we analyzed the BA profiles in cerebral cortex, hippocampus, and hypothalamus of young and natural aging mice of both sexes. The results showed that aging altered brain BA profiles sex- and region- dependently, in which TßMCA was consistently elevated in aging mice of both sexes, particularly in the hippocampus and hypothalamus. Furthermore, we found that aging accumulated-TßMCA stimulated microglia inflammation in vitro and shortened the lifespan of C. elegans, as well as behavioral impairment and neuroinflammation in mice. In addition, metagenomic analysis suggested that the accumulation of brain TßMCA during aging was partially attributed to reduction in BSH-carrying bacteria. Finally, rejuvenation of gut microbiota by co-housing aged mice with young mice restored brain BA homeostasis and improved neurological dysfunctions in natural aging mice. In conclusion, our current study highlighted the potential of improving aging-related neuro-impairment by targeting gut microbiota-brain BA axis.

Recent advances in the treatment of gout with NLRP3 inflammasome inhibitors.

Gout is an autoinflammatory disorder characterized by the accumulation of monosodium urate crystals in joints and other tissues, representing the predominant type of inflammatory arthritis with a notable prevalence and propensity for severe outcomes. The NLRP3 inflammasome, a member of the pyrin domain-containing NOD-like receptor family, exerts a substantial impact on both innate and adaptive immune responses and serves as a pivotal factor in the pathogenesis of gout. In recent years, there has been significant academic and industrial interest in the development of NLRP3-targeted small molecule inhibitors as a promising therapeutic approach for gout. To assess the advancements in NLRP3 inflammasome inhibitors for gout treatment, this review offers a comprehensive analysis and evaluation of current clinical candidates and other inhibitors targeting NLRP3 inflammasome from a chemical structure standpoint, with the goal of identifying more efficacious options for clinical management of gout.

Gut microbiota remodeling improves natural aging-related disorders through Akkermansia muciniphila and its derived acetic acid.

Accumulating evidence indicates gut microbiota contributes to aging-related disorders. However, the exact mechanism underlying gut dysbiosis-related pathophysiological changes during aging remains largely unclear. In the current study, we first performed gut microbiota remodeling on old mice by fecal microbiota transplantation (FMT) from young mice, and then characterized the bacteria signature that was specifically altered by FMT. Our results revealed that FMT significantly improved natural aging-related systemic disorders, particularly exerted hepatoprotective effects, and improved glucose sensitivity, hepatosplenomegaly, inflammaging, antioxidative capacity and intestinal barrier. Moreover, FMT particularly increased the abundance of fecal A.muciniphila, which was almost nondetectable in old mice. Interestingly, A.muciniphila supplementation also exerted similar benefits with FMT on old mice. Notably, targeted metabolomics on short chain fatty acids (SCFAs) revealed that only acetic acid was consistently reversed by FMT. Then, acetic acid intervention exerted beneficial actions on both Caenorhabditis elegans and natural aging mice. In conclusion, our current study demonstrated that gut microbiota remodeling improved natural aging-related disorders through A.muciniphila and its derived acetic acid, suggesting that interventions with potent stimulative capacity on A. muciniphila growth and production of acetic acid was alternative and effective way to maintain healthy aging. DATA AVAILABILITY STATEMENT: The data of RNAseq and 16 S rRNA gene sequencing can be accessed in NCBI with the accession number PRJNA848996 and PRJNA849355.

Bacterial Community Survey of Wolbachia-Infected Parthenogenetic Parasitoid Trichogramma pretiosum (Hymenoptera: Trichogrammatidae) Treated with Antibiotics and High Temperature.

Wolbachia has been shown to induce thelytokous parthenogenesis in Trichogramma species, which have been widely used as biological control agents around the world. Little is known about the changes of bacterial community after restoring arrhenotokous or bisexual reproduction in the T. pretiosum. Here, we investigate the emergence of males of T. pretiosum through curing experiments (antibiotics and high temperature), crossing experiments, and high-throughput 16S ribosomal RNA sequencing (rRNA-seq). The results of curing experiments showed that both antibiotics and high temperatures could cause the thelytokous T. pretiosum to produce male offspring. Wolbachia was dominant in the thelytokous T. pretiosum bacterial community with 99.01% relative abundance. With the relative abundance of Wolbachia being depleted by antibiotics, the diversity and relative content of other endosymbiotic bacteria increased, and the reproductive mode reverted from thelytoky to arrhenotoky in T. pretiosum. Although antibiotics did not eliminate Wolbachia in T. pretiosum, sulfadiazine showed an advantage in restoring entirely arrhenotokous and successive bisexual reproduction. This study was the first to demonstrate the bacterial communities in parthenogenetic Trichogramma before and after antibiotics or high-temperature treatment. Our findings supported the hypothesis that Wolbachia titer-dependence drives a reproduction switch in T. pretiosum between thelytoky and arrhenotoky.

Dietary rutin improves breast meat quality in heat-stressed broilers and protects mitochondria from oxidative attack via the AMPK/PINK1-Parkin pathway.

BACKGROUND: This study was conducted to investigate the effect of dietary rutin on the meat quality, antioxidant status and mitochondrial structure and function in the breast muscle of heat-stressed broilers. A total of 192 male broilers were randomly assigned into three groups and treated with normal control (CON), heat stress (34 °C, HS), and HS with 500 mg kg-1 rutin supplementation (HS + Rutin), respectively. RESULTS: Dietary rutin significantly reversed HS-induced decrease in body weight, average daily feed intake, average daily gain, and feed efficiency. Rutin supplementation attenuated HS-induced impaired meat quality by decreasing the lightness, drip loss at 24 and 48 h, the peak time of free water (T22 ) and the peak area ratio of free water (P22 ), and increasing the pH24h and peak area ratio of immobilized water (P21 ). Rutin supplementation promoted superoxide dismutase, glutathione peroxidase activities and total antioxidant capacity, and decreased malondialdehyde levels compared with the HS group. Moreover, rutin attenuated HS-induced mitochondrial damage by increasing the mitochondrial DNA copy number and improving mitochondrial morphology. Dietary rutin significantly increased mitochondrial biogenesis-related mRNA (proliferator-activated γ receptor coactivator-1α [PGC-1α], nuclear respiratory factor 1 [NRF1], and mitochondrial transcription factor A [TFAM]) expression via the AMP-activated protein kinase (AMPK) signaling pathway. HS significantly increased mitophagy-related genes and proteins (Parkin, PTEN-induced putative kinase 1 [PINK1], microtubule associated protein light chain 3-II [LC3-II]) expression, and dietary rutin significantly reversed these alterations. CONCLUSION: Dietary rutin attenuated the HS-induced decline in meat quality and antioxidant capacity of broilers, which may be related to inhibition of the AMPK/PINK1-Parkin signaling pathway to attenuate mitochondrial damage. © 2023 Society of Chemical Industry.

Simultaneous quantitative analysis of ten bioactive flavonoids in Citri Reticulatae Pericarpium Viride (Qing Pi) by ultrahigh-performance liquid chromatography and high-resolution mass spectrometry combined with chemometric methods.

INTRODUCTION: Citri Reticulatae Pericarpium Viride (Qing Pi in Chinese) is a clinically effective Chinese herb, which contains biologically valuable flavonoids. Qing Pi is divided into two commodity specifications, Si Hua Qing Pi (SHQP) and Ge Qing Pi (GQP), based on the harvesting time. The flavonoid contents in Qing Pi from different origins and commodity specifications may vary significantly, which will affect their therapeutic functions. Thus, it is crucial to set up a reliable and comprehensive quality evaluation method for flavonoid analysis in Qing Pi. OBJECTIVES: We aimed to establish a rapid and sensitive ultrahigh-performance liquid chromatography method coupled with diode-array detection and high-resolution mass spectrometry (UPLC-DAD-HRMS) for identification and quantification of ten flavonoids in Qing Pi. Chemometric methods were further applied to distinguish Qing Pi of different origins and specifications. METHODOLOGY: An UPLC-DAD-HRMS method was developed for the simultaneous separation and quantification of ten flavonoids in 46 batches of Qing Pi samples from different sources in China. Chemometric approaches were applied to discriminate Qing Pi from different origins and commodity specifications. RESULTS: The chemometric procedures (i.e., hierarchical clustering analysis and principal component analysis) were employed to identify the differences of Qing Pi samples with different origins and commodity specifications. The results showed that the contents of ten flavonoids in Qing Pi samples of different origins were significantly different, and the same results were found out between SHQP and GQP. CONCLUSIONS: This study provides a chemical basis for quality control of Qing Pi.

Activated biochar derived from spent Auricularia auricula substrate for the efficient adsorption of cationic azo dyes from single and binary adsorptive systems.

In this study, spent Auricularia auricula substrate (AS)-derived biochar (ASBCs) and activated biochar with NaOH (A-ASBC) were evaluated for the adsorption of cationic azo dyes, including methylene blue (MB), rhodamine B (RB), and crystal violet (CV), from single and binary adsorptive systems. A-ASBC showed a higher maximum adsorption capacity for these dyes (MB: 53.62 mg·g-1, RB: 32.33 mg·g-1, CV: 735.73 mg·g-1) than ASBCs in a single system because it had a greater specific surface area and more oxygen containing-functional groups on the surface. The adsorption process of the three dyes onto the adsorbents was in good agreement with the Freundlich adsorption isotherm and fit the pseudo-second-order kinetic model, which revealed sorbate polymolecular layer formation over the adsorbent surface and the involvement of chemisorption. The adsorption mechanism showed that the adsorption of three dyes on adsorbents could be postulated as a multistep process with extraordinary affinity-induced adsorption in terms of both physisorption and chemisorption. In the binary adsorptive system, the results showed that all MB, RB, and CV had antagonistic/competitive effects on each other's adsorption (QBinary/QSingle < 1). Furthermore, a phytotoxic assay affirmed the effectiveness of the adsorbent in adsorbing dye species from aqueous solutions using Brassica pekinensis L. seeds as the model. Therefore, activated biochar prepared from AS can be used as a potentially economical and effective adsorbent for treating printing and dyeing wastewater.

Prognostic Role of Time to Surgery in Hepatocellular Carcinoma at Barcelona Clinic Liver Cancer Stage 0-A.

BACKGROUND: Postsurgical recurrence is common in early-stage hepatocellular carcinoma (HCC). Prolonged time to surgery (TTS) may lead to tumor progression. However, the impact of TTS on HCC prognosis is controversial in Western studies and unknown in China. We aim to investigate the impact of TTS on the prognosis of Chinese HCC patients at Barcelona Clinic Liver Cancer (BCLC) stage 0-A who underwent surgery. PATIENTS AND METHODS: We retrospectively enrolled 967 BCLC 0-A HCC patients who underwent surgery at three tertiary centers in China. Primary outcomes were recurrence-free survival (RFS) and overall survival (OS). Restricted cubic spline (RCS) was used to select the cutoff value of TTS. Propensity score matching (PSM) was performed to reduce confounding bias, and a time-dependent Cox model was utilized to investigate factors influencing TTS. RESULTS: The median TTS of BCLC 0-A HCC patients was 13 days (interquartile range: 10-21 days). For patients with TTS ≤ 70 days, the cutoff value of TTS was 13 days according to RCS. After PSM, corresponding 1-, 3-, and 5-year RFS of the TTS > 13 days and TTS ≤ 13 days groups were 75.6%, 55.3%, 46.4% and 71.2%, 52.3%, 38.8%, respectively (P = 0.103). Corresponding 1-, 3-, and 5-year OS of TTS > 13 days and TTS ≤ 13 days groups were 93.7%, 82.8%, 69.6% and 92.4%, 78.5%, 68.4%, respectively (P = 0.580). Time-dependent Cox analysis revealed that age and tumor size were factors influencing TTS. CONCLUSIONS: Our study suggests that, for patients with TTS ≤ 70 days, prolonged TTS had no impact on BCLC 0-A Chinese HCC patients receiving surgery.

Simultaneous quantitative analysis of nine constituents in six Chinese medicinal materials from Citrus genus by high-performance liquid chromatography and high-resolution mass spectrometry combined with chemometric methods.

In this study, we aim to determine the chemical constituents of six Chinese medicinal materials from the Citrus genus using high-performance liquid chromatography and high-resolution mass spectrometry. Eight flavonoids and one coumarin were identified and further quantified as marker substances by high-performance liquid chromatography method. The separation was performed on an Agilent TC-C18 column with 0.1% formic acid and acetonitrile as the mobile phase under gradient elution. The analytical method was fully validated in terms of linearity, sensitivity, intra- and inter-day precision and repeatability, limit of detection, limit of quantitation, and recovery. It was subsequently applied to evaluate the quality of 103 batches of the Chinese medicinal materials from the Citrus genus. In addition, the principal constituent analysis was used to compare the samples of different species from the Citrus genus leading to successful classification of the samples in accordance with their origins. It was found that the contents of nine constituents varied greatly in different ripening stages and varieties of the samples from the Citrus genus. In addition, neoeriocitrin and 5,7-dimethoxycoumarin were determined as two unique constituents of 'Zhiqiao' and 'Foshou', respectively. In conclusion, this study provides a chemical basis for quality control of Chinese medicinal materials from the Citrus genus.

Significance of plasma MACC1 levels on the prognostic stratification in patients with colorectal cancer.

The clinical significance of metastasis-associated in colon cancer-1 (MACC1) has been investigated but the relevance of peripheral MACC1 levels was rather limited. Herein, our data revealed that plasma MACC1 levels in 117 colorectal cancer patients (CRC) were dramatically higher than that in normal controls (P < 0.001), and with a strong discrimination power between the two groups (AUC = 0.960, P < 0.001). Moreover, MACC1 is an independent prognostic factor for CRC patients. When clinical parameters stratified by MACC1low and MACC1high , MACC1 levels exhibited further significant predictive value. Summary, plasma MACC1 levels could be a useful prognostic and diagnostic biomarker, and could improve the prognostic value of traditional prognosticators for colorectal cancer patients.

Preoperative prediction of microvascular invasion in hepatocellular cancer: a radiomics model using Gd-EOB-DTPA-enhanced MRI.

OBJECTIVES: Preoperative prediction of microvascular invasion (MVI) in patients with hepatocellular cancer (HCC) is important for surgery strategy making. We aimed to develop and validate a combined intratumoural and peritumoural radiomics model based on gadolinium-ethoxybenzyl-diethylenetriamine (Gd-EOB-DTPA)-enhanced magnetic resonance imaging (MRI) for preoperative prediction of MVI in primary HCC patients. METHODS: This study included a training cohort of 110 HCC patients and a validating cohort of 50 HCC patients. All the patients underwent preoperative Gd-EOB-DTPA-enhanced MRI examination and curative hepatectomy. The volumes of interest (VOIs) around the hepatic lesions including intratumoural and peritumoural regions were manually delineated in the hepatobiliary phase of MRI images, from which quantitative features were extracted and analysed. In the training cohort, machine-learning method was applied for dimensionality reduction and selection of the extracted features. RESULTS: The proportion of MVI-positive patients was 38.2% and 40.0% in the training and validation cohort, respectively. Supervised machine learning selected ten features to establish a predictive model for MVI. The area under the receiver operating characteristic curve (AUC), sensitivity, specificity of the combined intratumoural and peritumoural radiomics model in the training and validation cohort were 0.85 (95% confidence interval (CI), 0.77-0.93), 88.2%, 76.2%, and 0.83 (95% CI, 0.71-0.95), 90.0%, 75.0%, respectively. CONCLUSIONS: We evaluate quantitative Gd-EOB-DTPA-enhanced MRI image features of both intratumoural and peritumoural regions and provide an effective radiomics-based model for the prediction of MVI in HCC patients, and may therefore help clinicians make precise decisions regarding treatment before the surgery. KEY POINTS: • An effective radiomics model for prediction of microvascular invasion in HCC patients is established. • The radiomics model is superior to the radiologist in prediction of MVI. • The radiomics model can help clinicians in pretreatment decision making.

Chronic heat stress alters hypothalamus integrity, the serum indexes and attenuates expressions of hypothalamic appetite genes in broilers.

The hypothalamus is crucial to ensure the functionality of the entire organisms, such as body temperature, feed intake and energy regulation. Exposing broilers to high ambient temperature usually induces lower feed intake and energy imbalance. We investigated the molecular mechanisms by which heat stress impairs the appetite via dysfunction in hypothalamus of the broilers. Broilers were allocated to three groups: the normal control (NC) group, and fed ad libitum; heat-stress (HS) group, and fed ad libitum; pair-fed (PF) group, which received the feed intake equal to HS group. Experiment lasted from the age of 28 to 42 d. The results showed that HS increased the head surface temperature of broiler and changed hypothalamic ultrastructure. HS treatment also increased the serum corticosterone in the broilers after 7 days of heat stress, elevated the FT4 and FT3 after 14 days of heat stress. Heat stress of 14 days showed a tendency to increase the leptin. However, the serum corticosterone in the HS group had no significant difference after 14 days of heat stress. In addition, HS treatment decreased the expression of orexigenic gene neuropeptide Y (NPY) after 14 days of heat stress, while HS treatment had no effect on the reactive oxygen species (ROS), as well as the gene expression of AMPKα1 and LKB1 in the hypothalamus. In conclusion, HS increased the surface temperature of head in broiler, and then altered the integrity of hypothalamus. Meanwhile, HS increased the serum corticosterone which may ascribe to the activation of HPA axis in the broilers. In addition, chronic heat stress decreased the expression of orexigenic gene NPY, which may cause the broiler to reduce feed intake.

Dietary taurine supplementation decreases fat synthesis by suppressing the liver X receptor α pathway and alleviates lipid accumulation in the liver of chronic heat-stressed broilers.

BACKGROUND: Chronic heat stress can enhance fat synthesis and result in lipid accumulation in the liver of broilers. To investigate the effects and molecular mechanisms of dietary taurine supplementation on fat synthesis and lipid accumulation in the liver of chronic heat-stressed broilers, 144 28 day-old chickens (Arbor Acres) were randomly distributed to normal control (NC, 22 °C, basal diet), heat stress (HS, consistent 32 °C, basal diet), or heat stress plus taurine (HS + T, consistent 32 °C, basal diet +5.00 g kg-1 taurine) groups for a 14-day feeding trial. RESULTS: Compared with those of the HS group, dietary taurine supplementation significantly decreased the level of very-low-density lipoprotein and the activity of aspartate aminotransferase in plasma and the relative weight of liver in the HS + T group. In addition, dietary taurine supplementation also significantly decreased the levels of triglyceride, acyl-CoA carboxylase (ACC) and fatty acid synthase (FAS), and suppressed the mRNA expression levels of liver X receptor α (LXRα), sterol response element-binding protein 1c, ACC and FAS in the liver of chronic heat-stressed broilers. Meanwhile, dietary taurine supplementation effectively alleviated lipid accumulation in the liver of broilers exposed to chronic heat stress. CONCLUSION: Chronic heat stress significantly increased fat synthesis and resulted in excess lipid deposition in the liver of broilers. Dietary taurine supplementation can effectively decrease fat synthesis by suppressing the LXRα pathway and alleviate lipid accumulation in the liver of chronic heat-stressed broilers. © 2019 Society of Chemical Industry.

Dietary taurine supplementation improves breast meat quality in chronic heat-stressed broilers via activating the Nrf2 pathway and protecting mitochondria from oxidative attack.

BACKGROUND: Chronic heat stress can induce oxidative impairment and decrease breast meat quality in broilers. Taurine is a ß-amino acid with antioxidant properties. To investigate the alleviative effects and molecular mechanisms of taurine supplementation on breast meat quality in broilers exposed to chronic heat stress, 144 28-day-old chickens (Arbor Acres) were randomly distributed to thermoneutral (TN, 22 °C, basal diet), heat stress (HS, consistent 32 °C, basal diet), or heat stress plus taurine (HS + T, consistent 32 °C, basal diet + 5.00 g kg-1 taurine) groups for a 14-day trial. RESULTS: Chronic heat stress did not affect the contents of moisture, crude protein and crude fat in breast muscle, but impaired breast meat quality in broilers. Taurine supplementation significantly alleviated the increase in lightness and drip loss and the decrease in pH45 min and shear force of breast meat in chronic heat-stressed broilers. Compared with the HS group, taurine supplementation significantly decreased the levels of reactive oxygen species and malonaldehyde and increased the messenger RNA expressions of nuclear factor erythroid 2-related factor 2 (Nrf2), NAD(P)H quinone dehydrogenase 1 and heme oxygenase 1 in the HS + T group. Meanwhile, taurine supplementation effectively alleviated mitochondrial damage caused by chronic heat exposure. CONCLUSION: Dietary taurine supplementation can effectively improve the quality of breast meat in chronic heat-stressed broilers via activating the Nrf2 pathway and protecting mitochondria from oxidative attack. © 2018 Society of Chemical Industry.

Serum metabolomics study of nutrient metabolic variations in chronic heat-stressed broilers.

To investigate the effects of heat stress on broiler metabolism, we assigned 144 broilers to normal control (NC), heat stress (HS) or pair-fed (PF) groups and then monitored the effects using growth performance, carcass characteristics, biochemical assays and GC-MS-based metabolomics. The up-regulation of cloacal temperature confirmed that our experiment was successful in inducing chronic heat stress. The average daily gain and average daily feed intake of the HS group were significantly lower than those of the NC group, by 28·76 and 18·42 %, respectively (P1 and P<0·05). The greater feed:gain ratio of the HS group was significantly positively correlated with the leg, abdominal fat, subcutaneous fat and intramuscular fat proportions and levels of some free amino acids (proline, l-cysteine, methionine and threonine) but was negatively correlated with breast proportion and levels of some NEFA (stearic acid, arachidonic acid, palmitic acid and oleic acid). These findings indicated that the heat-stressed broilers were in negative energy balance and unable to effectively mobilise fat, thereby resulting in protein decomposition, which subsequently affected growth performance and carcass characteristics.

Effects of chronic heat exposure on growth performance, intestinal epithelial histology, appetite-related hormones and genes expression in broilers.

BACKGROUND: Heat stress often occurs in the modern poultry industry, which impairs growth performance, particularly via reducing appetite. This study was aimed to investigate the mechanism of attenuating appetite by chronic heat exposure in broilers. A total of 144 broilers (28 days old) were allocated to normal control (NC, 22 °C), heat stress (32 °C), and pair-fed (22 °C) groups. RESULTS: Chronic heat exposure significantly increased cloacal temperatures and respiration rates, decreased the average daily feed intake and average daily gain, increased feed-to-gain ratio compared with the NC group, and elevated the concentrations of ghrelin and cholecystokinin (CCK) both in serum and intestine, as well as peptide YY and somatostatin in intestine on 35- or 42-day-old broilers. Moreover, heat exposure decreased villi height (VH) and the ratio of VH to crypt depth (CD), while it increased CD in the jejunum on 35- and 42 day-olds, increased (P < 0.05) the concentrations of valine and isoleucine in plasma on 42 days, and upregulated (P < 0.05) the expression of taste receptor type 1 members 1 and 3 (T1R1 and T1R3), CCK, and ghrelin in the intestine on 35- or 42-day-old broilers. CONCLUSION: Chronic heat exposure impairs the performance, intestinal morphology and appetite, which may be correlated with the increased secretion or gene expression of appetite-related hormones and genes, and the higher expression of nutrient-sensing receptors (T1R1 and T1R3) in broilers. © 2018 Society of Chemical Industry.

Bacterial community radial-spatial distribution in biofilms along pipe wall in chlorinated drinking water distribution system of East China.

Biofilms in the pipe wall may lead to water quality deterioration and biological instability in drinking water distribution systems (DWDSs). In this study, bacterial community radial-spatial distribution in biofilms along the pipe wall in a chlorinated DWDS of East China was investigated. Three pipes of large diameter (300, 600, and 600 mm) were sampled in this DWDS, including a ductile cast iron pipe (DCIP) with pipe age of 11 years and two gray cast iron pipes (GCIP) with pipe ages of 17 and 19 years, and biofilms in the upper, middle, and lower parts of each pipe wall were collected. Real-time quantitative polymerase chain reaction (qPCR) and culture-based method were used to quantify bacteria. 454 pyrosequencing was used for bacterial community analysis. The results showed that the biofilm density and total solid (TS) and volatile solid (VS) contents increased gradually from the top to the bottom along the pipe wall. Microorganisms were concentrated in the upper and lower parts of the pipe wall, together accounting for more than 80 % of the total biomass in the biofilms. The bacterial communities in biofilms were significantly different in different areas of the pipe wall and had no strong interaction. Compared with the upper and lower parts of the pipe wall, the bacterial community in the middle of the pipe wall was distributed evenly and had the highest diversity. The 16S rRNA genes of various possible pathogens, including Escherichia coli, Staphylococcus epidermidis, Pseudomonas aeruginosa, and Salmonella enterica, were detected in the biofilms, and the abundances of these possible pathogens were highest in the middle of the pipe wall among three areas. The detachment of the biofilms is the main reason for the deterioration of the water quality in DWDSs. The results of this study suggest that the biofilms in the middle of the pipe wall have highly potential risk for drinking water safety, which provides new ideas for the study of the microbial ecology in DWDS.

Production of Transgenic Pigs with an Introduced Missense Mutation of the Bone Morphogenetic Protein Receptor Type IB Gene Related to Prolificacy.

In the last few decades, transgenic animal technology has witnessed an increasingly wide application in animal breeding. Reproductive traits are economically important to the pig industry. It has been shown that the bone morphogenetic protein receptor type IB (BMPR1B) A746G polymorphism is responsible for the fertility in sheep. However, this causal mutation exits exclusively in sheep and goat. In this study, we attempted to create transgenic pigs by introducing this mutation with the aim to improve reproductive traits in pigs. We successfully constructed a vector containing porcine BMPR1B coding sequence (CDS) with the mutant G allele of A746G mutation. In total, we obtained 24 cloned male piglets using handmade cloning (HMC) technique, and 12 individuals survived till maturation. A set of polymerase chain reactions indicated that 11 of 12 matured boars were transgene-positive individuals, and that the transgenic vector was most likely disrupted during cloning. Of 11 positive pigs, one (No. 11) lost a part of the terminator region but had the intact promoter and the CDS regions. cDNA sequencing showed that the introduced allele (746G) was expressed in multiple tissues of transgene-positive offspring of No.11. Western blot analysis revealed that BMPR1B protein expression in multiple tissues of transgene-positive F1 piglets was 0.5 to 2-fold higher than that in the transgene-negative siblings. The No. 11 boar showed normal litter size performance as normal pigs from the same breed. Transgene-positive F1 boars produced by No. 11 had higher semen volume, sperm concentration and total sperm per ejaculate than the negative siblings, although the differences did not reached statistical significance. Transgene-positive F1 sows had similar litter size performance to the negative siblings, and more data are needed to adequately assess the litter size performance. In conclusion, we obtained 24 cloned transgenic pigs with the modified porcine BMPR1B CDS using HMC. cDNA sequencing and western blot indicated that the exogenous BMPR1B CDS was successfully expressed in host pigs. The transgenic pigs showed normal litter size performance. However, no significant differences in litter size were found between transgene-positive and negative sows. Our study provides new insight into producing cloned transgenic livestock related to reproductive traits.

PPR protein PDM1/SEL1 is involved in RNA editing and splicing of plastid genes in Arabidopsis thaliana.

After transcription, most chloroplast precursor RNAs undergo further post-transcriptional processing including cleavage, editing, and splicing. Previous investigation has shown that the cleavage of the rpoA transcript and most editing sites, including accD-1, are defective in the knockout mutant of PDM1/SEL1, a PLS-type PPR protein, and that PDM1 is associated with the rpoA transcript. In this work, we found that the splicing of group II introns in trnK and ndhA is also affected in pdm1. Co-immunoprecipitation mass spectrometry experiments were performed to identify proteins that are associated with PDM1. We obtained 126 non-redundant proteins, of which MORF9 was reported to be involved in RNA editing in chloroplast. Yeast two-hybrid assays showed that PDM1 interacts directly with MORF9, MORF2, and MORF8. RNA immunoprecipitation showed that PDM1 associates with the transcripts of trnK and ndhA, as well as accD-1, suggesting that PDM1 is involved in RNA editing and splicing. Therefore, PDM1 is an important protein for post-transcriptional regulation in chloroplast.

Pyrosequencing analysis of bacterial communities in biofilms from different pipe materials in a city drinking water distribution system of East China.

Biofilms in drinking water distribution systems (DWDSs) could cause several types of problems, such as the deterioration of water quality, corrosion of pipe walls, and potential proliferation of opportunistic pathogens. In this study, ten biofilm samples from different pipe materials, including ductile cast iron pipe (DCIP), gray cast iron pipe (GCIP), galvanized steel pipe (GSP), stainless steel clad pipe (SSCP), and polyvinyl chloride (PVC), were collected from an actual DWDS to investigate the effect of pipe material on bacterial community. Real-time quantitative polymerase chain reaction (qPCR) and culture-based method were used to quantify bacteria. 454 pyrosequencing was used for bacterial community analysis. The results showed that the numbers of total bacteria and culturable heterotrophic bacteria from iron pipes were higher than that in PVC, while the numbers of Shigella and vibrios were low in biofilms from iron pipes. Bacterial community analysis showed that Hyphomicrobium or Desulfovibrio were the predominant microorganism in iron pipes, whereas Sphingomonas or Pseudomonas were dominant in other types of pipe. This study revealed differences in bacterial communities in biofilms among different pipe materials, and the results were useful for pipeline material selection in DWDSs.