mTORC2 acts as a gatekeeper for mTORC1 deficiency-mediated impairments in ILC3 development

Group 3 innate lymphoid cells (ILC3s) are mediators of intestinal immunity and barrier function. Recent studies have investigated the role of the mammalian target of rapamycin complex (mTOR) in ILC3s, whereas the mTORC1-related mechanisms and crosstalk between mTORC1 and mTORC2 involved in regulating ILC3 homeostasis remain unknown. In this study, we found that mTORC1 but not mTORC2 was critical in ILC3 development, IL-22 production, and ILC3-mediated intestinal homeostasis. Single-cell RNA sequencing revealed that mTORC1 deficiency led to disruption of ILC3 heterogeneity, showing an increase in differentiation into ILC1-like phenotypes. Mechanistically, mTORC1 deficiency decreased the expression of NFIL3, which is a critical transcription factor responsible for ILC3 development. The activities of both mTORC1 and mTORC2 were increased in wild-type ILC3s after activation by IL-23, whereas inhibition of mTORC1 by Raptor deletion or rapamycin treatment resulted in increased mTORC2 activity. Previous studies have demonstrated that S6K, the main downstream target of mTORC1, can directly phosphorylate Rictor to dampen mTORC2 activity. Our data found that inhibition of mTORC1 activity by rapamycin reduced Rictor phosphorylation in ILC3s. Reversing the increased mTORC2 activity via heterozygous or homozygous knockout of Rictor in Raptor-deleted ILC3s resulted in severe ILC3 loss and complete susceptibility to intestinal infection in mice with mTORC1 deficiency (100% mortality). Thus, mTORC1 acts as a rheostat of ILC3 heterogeneity, and mTORC2 protects ILC3s from severe loss of cells and immune activity against intestinal infection when mTORC1 activity is diminished.

Dietary isoleucine supplementation enhances growth performance, modulates the expression of genes related to amino acid transporters and protein metabolism, and gut microbiota in yellow-feathered chickens

This study investigated the effects of dietary isoleucine (Ile) on growth performance, intestinal expression of amino acid transporters, protein metabolism-related genes and intestinal microbiota in starter phase Chinese yellow-feathered chickens. Female Xinguang yellow-feathered chickens (n = 1,080, aged 1 d) were randomly distributed to 6 treatments, each with 6 replicates of 30 birds. Chickens were fed diets with 6 levels of total Ile (6.8, 7.6, 8.4, 9.2, 10.0, and 10.8 g/kg) for 30 d. The average daily gain and feed conversion ratio were improved with dietary Ile levels (P < 0.05). Plasma uric acid content and glutamic-oxalacetic transaminase activity were linearly and quadratically decreased with increasing dietary Ile inclusion (P < 0.05). Dietary Ile level had a linear (P < 0.05) or quadratic (P < 0.05) effect on the jejunal expression of ribosomal protein S6 kinase B1 and eukaryotic translation initiation factor 4E binding protein 1. The relative expression of jejunal 20S proteasome subunit C2 and ileal muscle ring finger-containing protein 1 decreased linearly (P < 0.05) and quadratically (P < 0.05) with increasing dietary Ile levels. Dietary Ile level had a linear (P = 0.069) or quadratic (P < 0.05) effect on the gene expression of solute carrier family 15 member 1 in jejunum and solute carrier family 7 member 1 in ileum. In addition, bacterial 16S rDNA full-length sequencing showed that dietary Ile increased the cecal abundances of the Firmicutes phylum, and Blautia, Lactobacillus, and unclassified_Lachnospiraceae genera, while decreased that of Proteobacteria, Alistipes, and Shigella. Dietary Ile levels affected growth performance and modulated gut microbiota in yellow-feathered chickens. The appropriate level of dietary Ile can upregulate the expression of intestinal protein synthesis-related protein kinase genes and concomitantly inhibit the expression of proteolysis-related cathepsin genes.

Dietary L-arginine supplementation enhances growth performance, intestinal antioxidative capacity, immunity and modulates gut microbiota in yellow-feathered chickens

This study investigated the effects of dietary Arginine (Arg) on performance, intestinal antioxidative capacity, immunity, and gut microbiota in Chinese yellow-feathered chickens. One thousand two hundred 1-day-old female Qingyuan partridge chickens were randomly assigned to 5 groups with 6 replicates of 40 birds each. Chickens were fed diets with 5 levels of total Arg (8.5, 9.7, 10.9, 12.1, and 13.3 g/kg) without antibiotics for 30 d. The ADFI, ADG, and feed conversion ratio were improved with dietary Arg levels (P < 0.05). The proportions of CD3⁺ and CD4⁺/CD8⁺ lymphocytes responded in a linear (P < 0.05) manner and those of CD4⁺ in a linear or quadratic (P < 0.05) manner as dietary Arg levels increased. Dietary Arg level had a linear (P < 0.05) or quadratic (P < 0.05) effect on the gene expression of glutathione peroxidase 1, heme oxygenase 1, nuclear factor erythroid 2-related factor 2, and the activities of glutathione peroxidase and total antioxidative capacity in the jejunum and ileum. The relative expression of IL-1β, myeloid differentiation primary response 88, and Toll-like receptor 4 decreased linearly (P < 0.05) in the ileum with increasing dietary Arg levels; secretory IgA contents were increased. In addition, sequencing data of 16S rRNA indicated that dietary Arg increased the relative abundance of Firmicutes phylum, Romboutsia and Candidatus Arthromitus genera, while decreased that of Clostridium sensu stricto 1. A diet containing 12.1 g Arg/kg promoted growth performance, intestinal antioxidation, and innate immunity and modulated gut microbiota in yellow-feathered chickens.

[Expression of myocyte enhancer factor 2B in mantle cell lymphoma and its clinical significance]

Objective: To investigate the expression of myocyte enhancer factor 2B (MEF2B) in mantle cell lymphomas (MCL), and to analyze the correlation between the expression of MEF2B and pathological subtypes, structural subtypes, SOX11 expression and its clinical significance. Methods: Paraffin-embedded tissues were stained with HE, immunohistochemistry (EnVision method) and fluorescence in situ hybridization (FISH) , in addition, the clinical and pathological data of 60 cases of MCL were collected at Sun Yat-sen University Foshan Hospital and Sun Yat-sen University Cancer Center from January,2002 to May, 2019 for analysis. Results: Of the 60 MCLs, males is predominant (M∶F=3∶1). Histologically, the typical MCL is the majority (classical MCL: variant type MCL=48 cases:12 cases) . Fifty cases were classified into non-complete FDC meshwork type MCL, and the remaining 10 cases were classified into the complete-FDC meshwork type MCL group. Patients with classical MCL were more than 60 years old. The coexistent lesion sites both node and extranode in pathological subtype or structural subtype was the most common lesion sites. SOX11(+) MCL was common in classical MCL (P=0.040) and tended to be complete-FDC meshwork type MCL (P=0.086). The expression rate of MEF2B in MCL was 60.0%(36/60). This rate of MEF2B in classical type, complete-FDC meshwork type and SOX11(+) MCL was significantly higher than that variant type, no complete-FDC meshwork type, SOX11(-)MCL (P<0.05), respectively. There was no difference in clinical characteristics of MCL between MEF2B positive and negative groups. Compared with SOX11(-)MCL, the percentage of MEF2B expressed in tumor cells of SOX11(+)MCL was significantly higher (P=0.027). The expression of MEF2B was not related to the proliferation of tumor cells (P=0.341). There was no significant difference in the survival rate between different expression groups of MEF2B and SOX11 (P=0.304 and P=0.819, respectively). Only the mortality of variant type (blastoid/pleomorphic) MCL within 2 years was significantly higher than that of classical type MCL (P<0.05). Conclusions: The expression of MEF2B in MCL is related to the pathological subtypes, structural subtypes and the expression of SOX11, but not to the proliferation and prognosis. The high mortality rate within 2 years is only found in variant MCL. However, the role of MEF2B in MCL needs to be further studied.

Research Status of New Designer Drug Methcathinone in Forensic Toxicology

Methcathinone, a new cathinone designer drug, which is structurally similar to amphetamine analogs, is a central nervous stimulant. Recently, there has been a worldwide rise in its popularity and abuse, and a growing number of cases with disability or even death is reported in several countries, resulting in public concern. The typical symptoms include accelerated heartbeat, high temperature, anxiety, depression, etc. Forensic studies on its toxicity mechanism are rare. This article reviews its toxicological effects, poisoning symptoms, poisoning and addiction mechanisms, and detection methods, to provide theoretical reference for future studies and guidance for related forensic identification.

Influence of dairy by-product waste milk on the microbiomes of different gastrointestinal tract components in pre-weaned dairy calves

The community structure of colonised bacteria in the gastrointestinal tracts (GITs) of pre-weaned calves is affected by extrinsic factors, such as the genetics and diet of the calves; however, the dietary impact is not fully understood and warrants further research. Our study revealed that a total of 6, 5, 2 and 10 bacterial genera showed biologically significant differences in the GITs of pre-weaned calves fed four waste-milk diets: acidified waste milk, pasteurised waste milk, untreated bulk milk, and untreated waste milk, respectively. Specifically, generic biomarkers were observed in the rumen (e.g., Bifidobacterium, Parabacteroides, Fibrobacter, Clostridium, etc.), caecum (e.g., Faecalibacterium, Oxalobacter, Odoribacter, etc.) and colon (e.g., Megamonas, Comamonas, Stenotrophomonas, etc.) but not in the faeces. In addition, the predicted metabolic pathways showed that the expression of genes related to metabolic diseases was increased in the calves fed untreated waste milk, which indicated that untreated waste milk is not a suitable liquid diet for pre-weaned calves. This is the first study to demonstrate how different types of waste milk fed to pre-weaned calves affect the community structure of colonised bacteria, and the results may provide insights for the intentional adjustment of diets and gastrointestinal bacterial communities.

Expression of TRPV6 and CaBP-D28k in the egg shell gland (uterus) during the oviposition cycle of the laying hen

1. The aim of this study was to investigate the localisation of the transient receptor potential vanilloid channel type 6 (TRPV6) in egg shell gland (ESG) and examine the dynamic expression of TRPV6 and Calbindin-d28k (CaBP-D28k), as well as the changes in concentration of total calcium (Ca), total inorganic phosphorus (P), alkaline phosphatase (ALP), parathyroid hormone (PTH) and calcitonin (CT) in plasma during the oviposition cycle. 2. The plasma ALP activity was notably increased at 8 h. In addition, plasma CT was highest at 0 h and significantly lower at 8 h. The change of plasma PTH concentration increased slightly post-oviposition and reached a maximum at 16 h. 3. Immunohistochemical analysis indicated that TRPV6 was strongly localised to the apical luminal epithelium of the mucosa. The mRNA levels of TRPV6 and CaBP-D28k in the ESG remained very low from 0 to 4.5 h, but were significantly increased at 16 h. Furthermore, Western blotting analysis showed that the expression of TRPV6 and CaBP-D28k also reached a maximum at 16 h and was different from the concentration of CaBP-D28k. 4. In conclusion, the epithelial Ca(2+) channel TRPV6 is strongly expressed in the epithelial cells of the eggshell gland, and the increase of TRPV6 and CaBP-D28k mRNA and protein expression during eggshell formation suggests that active Ca(2+) transcellular transport exerts significant effects in delivering active calcium in the ESG.

Potential implication of activating killer cell immunoglobulin-like receptor and HLA in onset of pulmonary tuberculosis

Killer cell immunoglobulin-like receptor (KIR) and human leucocyte antigen (HLA) play crucial role in maintaining immune homoeostasis and controlling immune responses. To investigate the influence of KIR and HLA-C ligands on the risk of pulmonary tuberculosis (PTB), we studied 200 patients who were confirmed to have PTB and 200 healthy controls on the different frequencies of KIR and HLA-C ligands. Genotyping of these genes was conducted by sequence-specific primer polymerase chain reaction (SSP-PCR) method. Gene frequencies were compared between PTB group and the control group by χ(2) test, and P < 0.05 was regarded as statistically significant. As a result, the frequency of KIR genotype A/B was increased in PTB than controls but A/A was decreased. Moreover, striking differences were observed in the frequencies of HLA-Cw*08 between the two groups. Besides, the frequencies of '2DL2/3 with C1' in PTB were increased compared with control group. In addition, individuals with no KIR2DS3 and no Cw*08 were higher in controls than in PTB. KIR2DS1 was increased in PTB when HLA-C group 2 alleles were missing. In conclusion, KIR and HLA-C gene polymorphisms were related to susceptibility to PTB.

Inhibitory activities of baicalin against renin and angiotensin-converting enzyme

CONTEXT

Baicalin has been characterized as the active compound and quality control marker in Scutellaria baicalensis Georgi, traditionally used as a hypotensive herb.

OBJECTIVES

To investigate the inhibitory activities of baicalin against renin and angiotensin-I converting enzyme (ACE) and their molecule mechanism of interactions.

METHODS

The fluorescence method using renin substrate 1(R-2932) and the spectroscopy method by Cushman were used to determine renin and ACE activities, respectively. The fluorescence quench techniques were used to characterize their interactions.

RESULTS

The results showed that baicalin inhibited renin activity with an IC(50) value of 120.36 µM and inhibited ACE activity with an IC(50) value of 2.24 mM in vitro. The fluorescence emission of both renin and ACE were efficiently quenched by baicalin and a complete quenching was achieved at a high concentration of baicalin. Furthermore, baicalin was more effective in quenching the fluorescence of renin (K(SV) = 60 × 10(3) M(-1)) than ACE (K(SV) = 17.1 × 10(3) M(-1)). The quenching of fluorescence of renin and ACE involved static interactions, which was characterized by the formation of quencher-enzyme complex. The baicalin-renin complex formed through three-sites binding including the active site with a binding constant of 796.15 × 10(13) M(-1), but there was only one binding site for the baicalin-ACE complex with a much smaller binding constant of 6.8 × 10(5) M(-1).

CONCLUSION

The inhibition activity of baicalin against renin was a result of the formation of stable complex through multisites binding including the active site, which could explain the higher inhibitory efficiency.

Localisation and expression of TRPV6 in all intestinal segments and kidney of laying hens

1. The aim of this study was to investigate the localisation and expression of the epithelial Ca2+ channel TRPV6 (transient receptor potential vanilloid channel type 6) in different intestinal segments and kidney of laying hens during peak lay. 2. Immunohistochemical analysis of the intestine indicated that TRPV6 was localised to the brush-border membranes of the duodenum, jejunum, ileum, caecum, and rectum. Expression was weaker in the rectum, and little or no expression was found in crypt and goblet cells. In addition, TRPV6 mRNA was quantified amongst different intestinal segments, and expression was highest in the duodenum and jejunum. Furthermore, Western blotting indicated that the duodenum expressed the greatest amount of TRPV6 and the rectum the least with the other segments expressing intermediate levels. 3. In the kidney, distinct immunopositive staining for TRPV6 was detected at the apical domain of the distal convoluted tubules (DCT) and medullary connecting tubules (CNT). Interestingly, distribution of TRPV6 extended to the proximal convoluted tubules (PCT). Furthermore, the kidney expressed lower TRPV6 mRNA and protein levels compared with that in the duodenum. 4. In conclusion, the epithelial Ca2+ channel TRPV6 is strongly expressed in the apical cells of the entire intestine and the renal tubules, suggesting that active Ca2+ transcellular transport plays a crucial role in dietary calcium (re)absorption in laying hens.

Frequent allelic loss at the FRA3B site in endemic nasopharyngeal carcinoma: association with clinical features and Epstein-Barr virus infection

In this study, we aimed to precisely define the patterns of allelic loss at the FRA3B site in endemic nasopharyngeal carcinoma and to determine whether an association exists between allelic loss, clinicopathological features and Epstein-Barr virus infection. We examined the loss of heterozygosity in 40 cases of nasopharyngeal carcinoma from an endemic area in southern China, using eight high dense, polymorphic, microsatellite markers within or flanking the FRA3B site. Loss of heterozygosity at the FRA3B region was shown in 31 (77.5 per cent) primary tumours. Loss of heterozygosity was found most frequently at the D3S1300 (55.6 per cent) and D3S2757 (50.0 per cent) loci. The common area of deletion was located between the D3S4103 and D3S4260 loci. In nasopharyngeal carcinoma, loss of heterozygosity at the FRA3B/fragile histidine triad locus correlated with the following clinicopathological parameters: tumour T-stage, lymph node status, clinical stage, tumour differentiation and serum antibody titres of immunoglobulin (Ig) A against Epstein-Barr virus capsid antigen. Significantly frequent loss of heterozygosity was observed in nasopharyngeal carcinoma with tumour stages T3 and T4, lymph node metastasis and advanced tumour-node-metastasis staging (III and IV). Very frequent loss of heterozygosity was also observed to correlate with World Health Organization type III nasopharyngeal carcinoma histopathology. We also found that nasopharyngeal carcinoma patients with high titres of IgA against Epstein-Barr virus capsid antigen showed very frequent loss of heterozygosity. Allelic loss at the FRA3B site occurs significantly more commonly in endemic nasopharyngeal carcinoma patients. This suggests that the region between D3S4103 and D3S4260 may represent a preferential molecular target in nasopharyngeal carcinogenesis.

HRTEM analysis of nanocrystallization during uniaxial compression of a bulk metallic glass at room temperature

Nanocrystallization during deformation of metallic glass at room temperature has significant implications to understand its deformation mechanism. We present here direct high-resolution transmission electron microscopy (HRTEM) observations of nanocrystallization in a Zr(55)AI(10)Ni(5)Cu(30) bulk metallic glass (BMG) fractured by uniaxial compression at room temperature. The formed nanocrystallites are Zr(2)Cu, with the average diameter of less than 10nm, and are distributed within the round-like regions of localized plastic deformation. We also show direct evidence of atomic neighbor distance increases associated with the shrinkage and broadening of diffused ring pattern from local deformed areas, which may enhance atomic mobility so that nanocrystallization occurred. Our results demonstrate that the origin of the room-temperature deformation of BMG can be attributed to the local atomic spacing increases induced by localization of plastic flow under uniaxial compression test.

Mutation and abnormal expression of the fragile histidine triad gene in nasopharyngeal carcinoma

OBJECTIVE

To determine alterations of fragile histidine triad (FHIT) gene in nasopharyngeal carcinoma and the correlation of FHIT gene with nasopharyngeal carcinogenesis.

STUDY DESIGN

Prospective study.

METHODS

A total of 28 nasopharyngeal carcinoma and 16 normal nasopharyngeal epithelium specimens were examined for abnormalities of FHIT gene by nested reverse-transcriptase-polymerase chain reaction and DNA sequencing.

RESULTS

The deletion of FHIT gene was not observed in 16 normal nasopharyngeal epithelium specimens. In 28 cases of nasopharyngeal carcinoma tissues, 12 (42.9%) exhibited FHIT aberrant transcripts. Complementary DNA sequencing revealed exonic deletion, small DNA insertion, synonymous mutation in exon 8, or frameshift mutation in exon 5.

CONCLUSIONS

The present results suggest that the FHIT gene may play an important role in the pathogenesis of nasopharyngeal carcinoma and may be one of the candidate tumor suppressor genes in nasopharyngeal carcinoma.

The chromosomal effect of birchen dust as determined by the micronucleus test

In a wood processing factory, the measured air concentration of birchen dust was 1.26 +/- 0.41 mg/m3, and the micronucleus frequency of peripheral blood lymphocytes in 83 workers exposed to wood dust was 1.13 +/- 2.83/1000, which was significantly higher (P < 0.01) than that of control group (0.51 +/- 1.41/1000). The number of exposed workers with positive micronucleus test was 9.6%, which was higher than that of control group (4.5%), but the difference was not significant (P > 0.05). The micronucleus test in mice treated with water extracts of unsteamed and unbaked birchen dust showed that the micronucleus frequencies in all treated groups were significantly higher than that of control group (P < 0.01) and there was also a dose response correlation (r = 0.96, P < 0.0005). The results of steamed and baked birchen dust extracts were significantly lower than those of the unsteamed and unbaked ones at the same doses (P < 0.001). This suggests that when the birchen dust is steamed at the temperature of 100 degrees C for 24 h or baked at the temperature of 80 degrees C, its inducing effect in micronucleus test could be lowered.

Effect of anisodine on acute forebrain ischemia-reperfusion damage in rats

AIM

To study the protective effect of anisodine (Ani) on acute forebrain ischemia-reperfusion injury in rats.

METHODS

Both vertebral arteries were occluded by electrocautery. Severe, but transient bilateral cerebral ischemia was produced by clamping both common carotid arteries in rats. Atomic absorption spectrophotometric and spectrophotometric methods were used to determine the contents of calcium and extravasated Evans blue (EB), respectively, remained in forebrain at 60-min recirculation after 30-min ischemia.

RESULTS

At 60-min recirculation, the brain calcium contents were increased from 112 +/- 6 micrograms/g brain dry weight in control (sham operation) group to 165 +/- 7 micrograms/g brain dry weight with marked increase of EB extravasation. Ani (2.5 mg.kg-1, i.p.), and scopolamine (Sco, 0.25 mg.kg-1, i.p.) decreased the elevated calcium and extravasated EB contents.

CONCLUSION

Ani prevented the brain from ischemia insults through reducing intracellular calcium accumulation resulted from ischemia and reperfusion.

Study on micronucleus frequency in peripheral lymphocytes in workers of match factories

This paper reports the results of the study of micronucleus frequency in peripheral lymphocytes in workers exposed to soft wood dust (poplar and linden wood) in match factories. 298 workers exposed to soft wood dust in three match factories were defined as exposure group and 45 waiters in a restaurant as control group. The frequency of micronucleus in peripheral lymphocytes was examined and the control's 95% confidential upper limit >, 4/1000 was defined as the standard to determine the positivity. The positive rate in the exposure group was 36.2% while that in the control group was only 4.4%; the difference is significant (P < 0.01). As the coefficient of correlation between length of work and positive rate was 0.86 (P < 0.01), a dose/time-response is in existence. Meanwhile, the analysis of relation between quantity of smoking and positive rate eliminated the effect of smoking on variation of positive rates. In this paper, we also discussed the relation between positive rates and wood dust concentrations in different worksites and we think that the volatile and unsteady substances in soft wood dust are micronucleus-inducing matters.