(P)ppGpp synthetase Rsh participates in rifampicin tolerance of persister cells in Brucella abortus in vitro.

Brucella abortus is facultative intracellular pathogen that causes chronic persistent infections and results in abortion and infertility in food animals. Recurrent infections can be one of the results of persister cells formation that transiently displays phenotypic tolerance to high dose of antibiotics treatment. We examined persister cells formation of B. abortus strain A19 in stationary phase and investigated a potential role for the (p)ppGpp synthetase Rsh in this process. We found that B. abortus stationary phase cells can produce higher levels of multi-drugs tolerant persister cells in vitro under high dose of antibiotics (20 × MIC) exposure than do exponential phase cells. Persister cell formation was also induced with environmental stressors pH 4.5, 0.01 M PBS (pH7.0), 2% NaCl and 25 °C, upon exposure to ampicillin, enrofloxacin and rifampicin. Persister cells were not formed following exposure to 1 mM H2O2. The numbers of persister cells were significantly increased following uptake of B. abortus stationary phase cells by RAW264.7 macrophages in contrast with cultures in TSB liquid medium. Environmental stressors to B. abortus significantly increased expression of rsh mRNA level. The rsh null mutant (Δrsh) formed significantly fewer persister cells than the complemented (CΔrsh) and wildtype (WT) strains under high dose of rifampicin in vitro. These data for the first time demonstrate that B. abortus can produce multi-drug tolerant persister cells in stationary phase. The (p)ppGpp synthetase Rsh is necessary for persister cell formation in B. abortus in the presence of rifampicin. On this basis, a new understanding of the recurrent infections of Brucella was advanced, thus provided a new basis for revelation of pathogenic mechanism of the chronic persistent infection in Brucella.

Alr Gene in Brucella suis S2: Its Role in Lipopolysaccharide Biosynthesis and Bacterial Virulence in RAW264.7.

Brucella suis, the causative agent of brucellosis, poses a significant public health and animal husbandry threat. However, the role of the alanine racemase (alr) gene, which encodes alanine racemase in Brucella, remains unclear. Here, we analyzed an alr deletion mutant and a complemented strain of Brucella suis S2. The knockout strain displayed an unaltered, smooth phenotype in acriflavine agglutination tests but lacked the core polysaccharide portion of lipopolysaccharide (LPS). Genes involved in the LPS synthesis were significantly upregulated in the deletion mutant. The alr deletion strain exhibited reduced intracellular viability in the macrophages, increased macrophage-mediated killing, and upregulation of the apoptosis markers. Bcl2, an anti-apoptotic protein, was downregulated, while the pro-apoptotic proteins, Bax, Caspase-9, and Caspase-3, were upregulated in the macrophages infected with the deletion strain. The infected macrophages showed increased mitochondrial membrane permeability, Cytochrome C release, and reactive oxygen species, activating the mitochondrial apoptosis pathway. These findings revealed that alanine racemase was dispensable in B. suis S2 but influenced the strain's rough features and triggered the mitochondrial apoptosis pathway during macrophage invasion. The deletion of the alr gene reduced the intracellular survival and virulence. This study enhances our understanding of the molecular mechanism underlying Brucella's survival and virulence and, specifically, how alr gene affects host immune evasion by regulating bacterial LPS biosynthesis.

Soybean GmSAUL1, a Bona Fide U-Box E3 Ligase, Negatively Regulates Immunity Likely through Repressing the Activation of GmMPK3.

E3 ubiquitin ligases play important roles in plant immunity, but their role in soybean has not been investigated previously. Here, we used Bean pod mottle virus (BPMV)-mediated virus-induced gene silencing (VIGS) to investigate the function of GmSAUL1 (Senescence-Associated E3 Ubiquitin Ligase 1) homologs in soybean. When two closely related SAUL1 homologs were silenced simultaneously, the soybean plants displayed autoimmune phenotypes, which were significantly alleviated by high temperature, suggesting that GmSAUL1a/1b might be guarded by an R protein. Interestingly, silencing GmSAUL1a/1b resulted in the decreased activation of GmMPK6, but increased activation of GmMPK3 in response to flg22, suggesting that the activation of GmMPK3 is most likely responsible for the activated immunity observed in the GmSAUL1a/1b-silenced plants. Furthermore, we provided evidence that GmSAUL1a is a bona fide E3 ligase. Collectively, our results indicated that GmSAUL1 plays a negative role in regulating cell death and immunity in soybean.

Comparison of pain relief and limb function improvement after extracorporeal shock wave therapy and thermomagnetic therapy in the treatment of low back pain.

Objective: To compare the rehabilitation effects of extracorporeal shock wave therapy (ESWT) and thermomagnetic therapy (TMT) in patients with low back pain (LBP). Methods: As a single-centre retrospective observational study, clinical data of patients with LBP who received rehabilitation treatment in our hospital from January 2020 to May 2021 were retrospectively collected. Based on the treatment mode, the patients were retrospectively divided into two groups: the control group (patients received core muscle training + TMT, n=51) and the observation group (patients received core muscle training + ESWT, n=56). The general data of the patients were collected and the groups were matched for age, gender and pain duration. The visual analogue scale (VAS) score of pain, improvement of limb function, ß-endorphin (ß-EP), prostaglandin E2 (PGE2) and nitric oxide (NO) were compared between the two groups before and after treatment. Results: The VAS scores of the observation group were lower than those of the control group at one, two weeks and one month after the treatment (P<0.05). After the treatment, the proportion of mild limb dysfunction in the observation group was 57.14% (32/56), which was higher than 35.29% (1 /51) in the control group. The proportion of patients with severe and obvious disorders was 0 and 5.36% (3/56), respectively, which was lower than 11.76% (6/51) and 5.88% (3/51) in the control group (P<0.05). After the treatment, levels of NO and PGE2 in the observation group were lower, and the level of ß-EP was significantly lower than in the control group (P<0.05). Conclusions: A combination of core muscle training and ESWT can effectively improve the analgesic effect of the treatment and promote greater improvement of limb function in patients with LBP.

BtpB inhibits innate inflammatory responses in goat alveolar macrophages through the TLR/NF-κB pathway and NLRP3 inflammasome during Brucella infection.

Brucella species are infectious facultative intracellular pathogens. They have evolved multiple strategies to thwart immune responses and replicate in macrophages for chronic persistence in the host. As a Brucella effector, BtpB is transferred into target cells through the type IV secretion system. BtpB, a Toll/interleukin-1 receptor domain-containing protein, blocks host innate immune responses by interfering with Toll-like receptor signaling. However, the intracellular targets and their activated downstream pathways remain unclear. In this study, we constructed a strain of Brucella suis S2 with a deletion in the gene for BtpB, ΔbtpB, and the complemented strain, C-ΔbtpB with a restored copy of the btpB gene. The bacterial growth curves and stress resistance results showed that BtpB did not affect B. suis S2 growth. Infection of alveolar macrophages with WT and ΔbtpB strains showed that BtpB inhibited TLR2 and TLR4 expression and attenuated NLRP3 inflammasome activation. BtpB also attenuated secretion of the Brucella-induced proinflammatory cytokines, IL-1ß, IL-6, and TNF-α, in alveolar macrophages while up-regulating IL-10 expression. In general, the results confirmed that BtpB specifically inhibits TLR2/TLR4 and disrupts NLRP3 signaling pathways to inhibit host immune responses in early Brucella infections.

Brucella BtpB Manipulates Apoptosis and Autophagic Flux in RAW264.7 Cells.

Brucella transfers effectors into host cells, manipulating cellular processes to its advantage; however, the mechanism by which effectors regulate cellular processes during infection is poorly understood. A growing number of studies have shown that apoptosis and autophagy are critical mechanisms for target cells to cope with pathogens and maintain cellular homeostasis. BtpB is a Brucella type IV secretion system effector with a complex mechanism for manipulating host infection. Here, we show that the ectopic expression of BtpB promoted DNA fragmentation. In contrast, an isogenic mutant strain, ΔbtpB, inhibited apoptosis compared to the wild-type strain B. suis S2 in RAW264.7 cells. In addition, BtpB inhibited autophagy, as determined by LC3-II protein levels, the number of LC3 puncta, and p62 degradation. We also found that BtpB reduced autophagolysosome formation and blocked the complete autophagic flux. Moreover, our results revealed that the autophagy inhibitor, chloroquine, reduces Brucella's intracellular survival. Overall, our data unveil new mechanisms of virulence implicating the effector BtpB in regulating host intracellular infection.

[Interaction of Chinese and western medicines in treatment of cardiovascular diseases].

Cardiovascular diseases are a global public health problem, and the combination of Chinese and western medicine tends to be a major solution in China. However, the complex components in traditional Chinese medicine may interact with the therapeutic western medicines for the diseases, which will lead to the herb-drug interaction(HDI). The information on the interaction can serve as a reference for the rational combination of the Chinese and western medicines in the clinical treatment of cardiovascular diseases and help avoid the occurrence of clinical safety events. However, the research on the interaction of Chinese medicine is limited as compared with that on western medicine, and no systematic review on HDI in the treatment of cardiovascular diseases is available. Therefore, this study first introduced the mechanism of HDI, then summarized the research on HDI for the commonly used drugs for cardiovascular diseases, analyzed the problems in the available studies, and put forward suggestions on the application, regulation, and research. This study aims to highlight HDI in clinical drug use and provide a reference for rational use of combination of Chinese and western medicines in the treatment of cardiovascular diseases.

An ArsR Transcriptional Regulator Facilitates Brucella sp. Survival via Regulating Self and Outer Membrane Protein.

The arsenic acid-resistant (ArsR) family transcriptional regulators are widely distributed in microorganisms, including in the facultative intracellular pathogen Brucella spp. ArsR proteins are implicated in numerous biological processes. However, the specific roles of ArsR family members in Brucella remain obscure. Here, we show that ArsR6 (BSS2_RS07325) is required for Brucella survival both under heat, oxidative, and osmotic stress and in a murine infection model in vivo. RNA-seq and ChIP-seq reveal that 34 potential target genes for ArsR6 protein were identified, among which eight genes were up-regulated and 26 genes were down-regulated, including outer membrane protein 25D (Omp25D). ArsR6 autoregulates its own expression to maintain bacterial intracellular Cu/Ni homeostasis to benefit bacterial survival in hostile environments. Moreover, ArsR6 also regulates the production of virulence factor Omp25D, which is important for the survival of Brucella under stress conditions. Significantly, Omp25D deletion strain attenuated in a murine infection model in vivo. Altogether, our findings reveal a unique mechanism in which the ArsR family member ArsR6 autoregulates its expression and also modulates Omp25D expression to maintain metal ion homeostasis and virulence in Brucella.

VceC Mediated IRE1 Pathway and Inhibited CHOP-induced Apoptosis to Support Brucella Replication in Goat Trophoblast Cells.

The effectors of the type IV secretion system (T4SS) of bacteria play important roles in mediating bacterial intracellular proliferation and manipulating host-related pathway responses to bacterial infection. Brucella Spp. inhibit the apoptosis of host cells to benefit their own intracellular proliferation. However, the underlying mechanisms between T4SS effectors and Brucella-inhibited apoptosis in goat trophoblast cells remain unclear. Here, based on Brucella suis vaccine strain 2, the VceC was deleted by allelic exchange. We show that ΔVceC was able to infect and proliferate to high titers in goat trophoblast cells (GTCs) and increase C/EBP-homologous protein (CHOP)-mediated apoptosis. GRP78 expression decreased upon ΔVceC infection. In addition, we discovered that the inositolrequiring enzyme 1 (IRE1) pathway was inhibited in this process. Changing endoplasmic reticulum (ER) stress affected Brucella intracellular replication in GTCs. The replication of ΔVceC was more sensitive under the different ERstress conditions in the GTC line after treatment with ER stress inhibitors 4 phenyl butyric acid (4-PBA) or ER stress activator Tm. Together, our findings show that VceC has a protective effect on the intracellular persistence of Brucella infection, and inhibits ER stress-induced apoptosis in the CHOP pathway. The present work provides new insights for understanding the mechanism of VceC in the establishment of chronic Brucella infection.

[Effects of sleep deprivation induced blood stasis syndrome on platelet activation in rats].

Blood stasis syndrome is the pre-state of thrombotic disease. The model of blood stasis syndrome in rats was induced by sleep deprivation to study on effects of blood stasis syndrome on platelet activation. The weight, the color of tongue and hemorheology for the blood stasis syndrome of Chinese medicine were measured after modeling. The release of platelet granules and platelet activation factors in plasma were detected by ELISA kit related indicators to provide experimental basis for platelet function evaluation and related drug effects in syndrome research. The results showed that the weight of the model group rats was significantly lower than that of the normal group (P<0.01). The tongue showed a dark purple blood stasis pattern, and the R, G and B values of the tongue surface in model group were significantly lower than those of the normal group (P<0.01). The hemorheological parameters including high shear, middle shear and low shear viscosity in whole blood were significantly higher than those in the normal group (P<0.01). But plasma viscosity did not change significantly. The release levels of platelet α particles (GMP-140, ß-TG, PF4) and dense particles (ADP, 5-HT) were significantly higher than those in the normal group (P<0.01). The levels of TXB2 and 6-keto-PGF1α in plasma were significantly higher than those in the normal group (P<0.01). The ratios of TXB2 and 6-keto-PGF2α were also significantly higher than those in the normal group (P<0.01). The levels of PAF in plasma in model group were significantly higher than those in the normal group (P<0.01). It was concluded that platelet functions could be changed induced by sleep deprivationin rats with blood stasis syndrome, and there might be inflammation and endothelial cell dysfunction.

[Characterization and pathophysiological changes of cerebral infarction rat model with qi-deficiency and blood-stasis Syndrome].

This study aimed to observe the general state and changes in pathophysiological indexes of multiple cerebral infarction rat model with Qi-deficienty and Blood-stasis syndrome. Rats were randomly divided into 4 groups(with 30 in each group): the normal group, the sham group, the model group and the Yiqi Huoxue recipe group. Rats in the model group and Yiqi Huoxue group were provided with interruptable sleep deprivation for 7 days before the multiple cerebral infarction operation, and followed by another 4 weeks of sleep deprivation; rats in the Yiqi Huoxue group were intragastrically administrated with drug at a dose of 26 g·kg⁻¹, once a day for 4 weeks. The general state was observed, and the pathophysiological indexes were measured at 48 h, 2 weeks and 4 weeks after administration. The results showed that rats in the normal group and the sham group represented a good general state and behaviors, with a normal morphological structure of brain tissues; rats in the model group featured yellow fur, depression, accidie, loose stools and movement disorder, with obvious brain histomorphological damage, which became aggravated with the increase of modeling time; rats in the Yiqi Huoxue group showed release in the general state and above indexes. Compared with the sham group at three time points, rats in the model group showed decrease in body weight, exhaustive swimming time and RGB value of tongue surface image, and increase in whole blood viscosity of the shear rate under 5, 60 and 150 S⁻¹, reduction in cerebral cortex Na⁺-K⁺-ATPase, Ca²âº-ATPase activity and contents of 5-HT, rise in TXB2 levels and decline in 6-keto-PGF1a in serum(P<0.05, P<0.01). Compared with the model group, rats in the Yiqi Huoxue group showed alleviations in the above indexes at 2 w and 4 w(P<0.05, P<0.01). The results showed that the characterization and pathophysiological indexes in the multiple cerebral infarction rat model with Qi-deficiency and blood-stasis syndrome were deteriorated; Yiqi Huoxue recipe could significantly alliviate the abnormal conditions, which suggested of the model was stable and reliable and the pathophysiologic evolutionary mechanism might be related to energy metabolism dysfunction, vasoactive substance abnormality and changes in neurotransmitters.

[Determination of aflatoxin B1, B2, G1, G2 in Ben Lamge granules by HPLC-FLD after multi-pretreatment clean-up].

To establish a multi-pretreatment method for the determination of aflatoxin B1, B2, G1, G2 in Chinese patent medicines, aflatoxins were analyzed by high performance liquid chromatography-fluorescence detector with post-column derivatization, after the multi-pretreatment of samples. The results showed that after the samples extracted with MeOH-H2O, dehydrated by anhydrous magnesium sulphate and sodium chloride, and finally purified by neutral alumina, the impurity interference of different sources in Chinese patent medicines matrix can be effectively removed, and the main peak can be nicely separated from the impurity peak. The detection limits were 0.25, 0.25, 0.50, 0.25 µg x L(-1) for AFB1, AFB2, AFG1, AFG2, respectively. The quantification limits were 1.00, 0.50, 1.00, 0.50 µg x L(-1), respectively. Aflatoxin B1, G1 showed a good linear relationship at a range of 1.0-50 µg x L(-1), aflatoxin B2, G2 at a range of 0.5-12.5 µg x L(-1) (R2 > 0.99). The average recovery was 80.40% - 108.6%. The present method is simple, reproducible with the reasonable recoveries and can be applied for the determination of aflatoxins in Chinese patent medicines.

[Clinical analysis of syndrome-relative biological indices in acute lacuna encephalon infarction patients of upper hyperactivity of Gan Yang syndrome].

OBJECTIVE: To analyze and summarize changes of syndrome-related biological indices in acute lacuna encephalon infarction patients of upper hyperactivity of Gan yang syndrome (UHGYS), thus providing objective evidence for syndrome typing and disease identification. METHODS: Recruited were 50 patients at Department of Encephalopathy, Xiyuan Hospital, China Academy of Chinese Medical Sciences, who were in line with diagnostic criteria of UHGYS as the experimental group in this study. Another 40 healthy volunteers were recruited as the control group from May 2010 to July 2012. Blood routines (including WBC, RBC, Hb, NEUT%, and LY%), hepatic and renal functions tests (including ALT, AST, TBIL, TP, ALB, Cr, and BUN) were performed by automatic whole blood analyzer and colorimetric technique. The levels of fasting blood glucose, HbAlc, blood lipids (including TC, TG, HDL-C, LDL-C, and VLDL-C), and coagulation functions (including AT-III, PT, PTA, INR, TT, APTT, and FBG, reaction time), renin, angiotensin II, hs-CRP, and Hcy were also measured. The thyroid functions (including FT3, FT4, T3, T4, and TSH) were detected by electrochemiluminescence immunoassay. The levels of tumor necrosis factor alpha (TNF-alpha), IL-6 and IL-1 in serum were measured by ELISA and radioimmunoassay respectively. RESULTS: Compared with the control group, RBC, LY%, ALT, TP, ALB, HDL-C, AT-III activities, contents of PTA and FT4 obviously decreased, TBIL, BUN, Glu, HbAlc, TSH, hs-CRP, renin, Ang II, TNF-alpha, IL-1 and IL-6 significantly increased in the experimental group (P < 0.05, P < 0.01). CONCLUSION: The pathological process of acute lacuna encephalon infarction patients of UHGYS was closely correlated with thyroid functions, the renin-angiotensin-aldosterone system, the extrinsic and intrinsic coagulation systems, as well as inflammation reaction.

[Effect of formula of removing both phlegm and blood stasis on inflammatory reaction in Chinese mini-swine with coronary atherosclerosis].

OBJECTIVE: To observe the effect of formula of removing both phlegm and blood stasis (TYTZ) in inhibiting the inflammatory reaction in Chinese mini-swine with coronary atherosclerosis. METHOD: Totally 36 Chinese mini-swine were randomly divided to six groups: the normal control group, the model group, the Shujiangzhi group and TYTZ groups with does of 2.0, 1.0 and 0.5 g x kg(-1), and six each in every group. Except for the normal control group, all of other groups were fed with high-fat diet for 2 weeks. Interventional balloons are adopted to injure their left anterior descending artery endothelium. After the operation, they were fed with high-fat diet for 8 weeks to prepare the coronary atherosclerosis model. In the 8th week after the operation and administration, the intravascular ultrasound was adopted to observe the coronary artery plaque burden of each group and the pathological morphology of coronary artery. Such inflammatory factors as high-sensitivity C-reactive protein (hs-CRP), tumor necrosis factor (TNF)-alpha and interleukin (IL)-6 were detected by ELISA. The expression of NF-kappaB p65 nuclear translocation was observed by the immunohistochemical method. RESULT: Compared with the normal control group, the model group showed significant increase in the coronary artery plaque burden at the end of the experiment (P < 0.01), notably abnormal structural changes in atherosclerotic vascular tissues, luminal stenosis, a large number of foam cells and inflammatory cell infiltration, remarkable growth of hs-CRP, TNF-alpha and IL-6 levels (P < 0.01). The immunohistochemical staining also showed the significant increase in the NF-kappaB p65 nuclear translocation of coronary artery of Chinese mini-swine in the model group. Compared with the model group, TYTZ could significantly attenuate atherosclerotic plaque burden (P < 0.01), inhibit the coronary luminal stenosis, reduce inflammatory cell infiltration, decrease such inflammatory cell factors as hs-CRP, TNF-alpha and IL-6 in serum, and inhibit the NF-kappaB p65 nuclear translocation of coronary artery (P < 0.05 or P < 0.01). CONCLUSION: TYTZ can reduce the downstream inflammatory reaction by controlling NF-kappaB p65 nuclear translocation, so as to inhibit the occurrence and development of coronary atherosclerotic plaque in Chinese mini-swine.

[Effect of formula of removing both phlegm and blood stasis in improving hemorheology and blood fat of mini-swine with coronary heart disease of phlegm-stasis cementation syndrome].

OBJECTIVE: To observe effect of formula of removing both phlegm and blood stasis (TYTZ) in improving hemorheology and blood fat of mini-swine with coronary heart disease of phlegm-stasis cementation syndrome. METHOD: Thirty-six Chinese mini-swine were randomly divided to six groups: the normal control group, the model group, the Shujiangzhi group and TYTZ groups with doses of 2.0, 1.0 and 0.5 g x kg(-1), with six mice in each group. Except for the normal control group, all of other groups were fed with high-fat diet for 2 weeks. Interventional balloons are adopted to injure their left anterior descending artery endothelium. After the operation, they were fed with high-fat diet for 8 weeks to prepare the coronary heart disease model of phlegm-stasis cementation syndrome. In the 8th week after the operation and administration, the changes in hemorheological parameters, serum lipid level, myocardial ischemia level and range were observed. RESULT: Compared with the normal control group, the model group showed significant increase in serum TC, TG, LDL-C and VLDL-C levels (P < 0.01), whole blood viscosity under the shear rate of 5 s (-1) and 60 s (-1) (P < 0.01), and myocardial ischemia degree and range (P < 0.01). Compared with the model group, TYTZ groups revealed significant decrease in myocardial ischemia degree and range (P < 0.01), serum TC, TG, LDL-C and VLDL-C levels (P < 0.05 or P < 0.01) and whole blood viscosity under the shear rate of 5 s(-1) and 60 s(-1) (P < 0.05). CONCLUSION: TYTZ could improve the abnormal hemorheology in Chinese mini-swine with coronary heart disease of phlegm-stasis cementation syndrome, and regulate serum lipid, with a certain efficacy for coronary heart disease of phlegm-stasis cementation syndrome.

The PTB and PRR domains of numb regulate neurite outgrowth by influencing voltage-gated calcium channel expression and kinetics.

Numb is an evolutionarily conserved protein that regulates the differentiation of neuronal progenitor cells through unknown mechanisms. Numb has four alternative splice variants with different lengths of phosphotyrosine-binding (PTB) and proline-rich regions (PRR) domains. In this study, we demonstrated that Numb expression was increased in the primary cultures of rat cortical and hippocampal neurons over time in vitro, and Numb antisense inhibited neurite outgrowth. We verified that cells overexpressing short PTB (SPTB) or long PTB (LPTB) domains exhibited differentiation or proliferation, respectively. SPTB-mediated differentiation was related to the PRR domains, as cells expressing SPTB/LPRR had longer dendrites and more branched dendrites than cells expressing SPTB/SPRR. The differentiation of both cell types was completely blocked by the Ca2+ chelator. Western blot analysis revealed the increased total protein expression of voltage-gated calcium channel (VGCC) subunit α1C and α1D in cells expressing SPTB and LPTB Numb. The increased expression of the VGCC ß3 subunit was only observed in cells expressing SPTB Numb. Immunocytochemistry further showed that SPTB-mediated cell differentiation was associated with increased membrane expression of VGCC subunits α1C, α1D and ß3, which corresponded to the higher Ca2+ current (ICa) densities. Furthermore, we found that VGCC of cells transfected with SPTB/SPRR or SPTB/LPRR Numb isoforms exhibit steady-state inactivation (SSI) in both differentiated and undifferentiated phenotypes. A similar SSI of VGCC was observed in the differentiated cells transfected with SPTB/SPRR or SPTB/LPRR Numb isoforms, whereas a left shift SSI of VGCC in cells expressing SPTB/LPRR was detected in the undifferentiated cells. Collectively, these data indicate that SPTB domain is essential for neurite outgrowth involving in membrane expression of VGCC subunits, and LPRR plays a role in neuronal branching and the regulation of VGCC inactivation kinetics.

Construction of a novel aminofluorene-based ratiometric near-infrared fluorescence probe for detecting carboxylesterase activity in living cells.

Herein, we constructed a novel aminofluorene-based fluorescence probe (FEN-CE) for the detection of carboxylesterase (CE) in living cells by a ratiometric near-infrared (NIR) fluorescence signal. FEN-CE with NIR emission (650 nm) could be hydrolyzed specifically by CE and transformed to FENH with the release of the self-immolative group, which exhibited a red-shifted emission peak of 680 nm. In addition, FEN-CE showed high selectivity for CE and was successfully used in the detection of CE activity in living cells through its ratiometric NIR fluorescence signals.

Mitochondria-Modulating Liposomes Reverse Radio-Resistance for Colorectal Cancer.

Complete remission of colorectal cancer (CRC) is still unachievable in the majority of patients by common fractionated radiotherapy, leaving risks of tumor metastasis and recurrence. Herein, clinical CRC samples demonstrated a difference in the phosphorylation of translation initiation factor eIF2α (p-eIF2α) and the activating transcription factor 4 (ATF4), whose increased expression by initial X-ray irradiation led to the resistance to subsequent radiotherapy. The underlying mechanism is studied in radio-resistant CT26 cells, revealing that the incomplete mitochondrial outer membrane permeabilization (iMOMP) triggered by X-ray irradiation is key for the elevated expression of p-eIF2α and ATF4, and therefore radio-resistance. This finding guided to discover that metformin and 2-DG are synergistic in reversing radio resistance by inhibiting p-eIF2α and ATF4. Liposomes loaded with metformin and 2-DG (M/D-Lipo) are thus prepared for enhancing fractionated radiotherapy of CRC, which achieved satisfactory therapeutic efficacy in both local and metastatic CRC tumors by reversing radio-resistance and preventing T lymphocyte exhaustion.

Deletion of the alr gene in Brucella suis S2 attenuates virulence by enhancing TLR4-NF-κB-NLRP3- mediated host inflammatory responses.

Brucella is an intracellular parasitic bacterium lacking typical virulence factors, and its pathogenicity primarily relies on replication within host cells. In this study, we observed a significant increase in spleen weight in mice immunized with a Brucella strain deleted of the gene for alanine racemase (Alr), the enzyme responsible for alanine racemization (Δalr). However, the bacterial load in the spleen markedly decreased in the mutant strain. Concurrently, the ratio of white pulp to red pulp in the spleen was increased, serum IgG levels were elevated, but no significant damage to other organs was observed. In addition, the inflammatory response was potentiated and the NF-κB-NLRP3 signaling pathway was activated in macrophages (RAW264.7 Cells and Bone Marrow-Derived Cells) infect ed with the Δalr mutant. Further investigation revealed that the Δalr mutant released substantial amounts of protein in a simulated intracellular environment which resulted in heightened inflammation and activation of the TLR4-NF-κB-NLRP3 pathway in macrophages. The consequent cytoplasmic exocytosis reduced intracellular Brucella survival. In summary, cytoplasmic exocytosis products resulting from infection with a Brucella strain deleted of the alr gene effectively activated the TLR4-NFκB-NLRP3 pathway, triggered a robust inflammatory response, and reduced bacterial survival within host cells. Moreover, the Δalr strain exhibits lower toxicity and stronger immunogenicity in mice.

[Significance of serum MMP-3, TIMP-1, and monocyte CD147 in rheumatoid arthritis patients of damp-heat Bi-syndrome and of cold-damp Bi-syndrome].

OBJECTIVE: To explore the clinical significance of serum matrix metalloproteinase-3 (MMP-3), tissue inhibitor of metalloproteinase-1 (TIMP-1), and monocyte CD147 in rheumatoid arthritis (RA) patients of damp-heat Bi-syndrome (DHBS) and of cold-damp Bi-syndrome (CDBS). METHODS: The clinical data of 22 patients from inpatients and outpatients with RA were collected, and their peripheral blood was withdrawal. The disease activity scores [DAS28(4)] were assessed. The serum levels of MMP-3 and TIMP-1 were detected by double antibody sandwich enzyme linked immunosorbent assay (ELISA). The mean fluorescence intensity (MFI) and the expression percentage of CD147 on CD14+ monocytes were detected by flow cytometry. The difference of each index between RA patients of DHBS and RA patients of CDBS was analyzed. RESULTS: The level of serum MMP-3 and the MFI of CD147 on the monocyte surface were obviously higher in RA patients of DHBS than in those of CDBS and the normal control group (P < 0.05). The concentration of serum TIMP-1 was obviously higher in RA patients of DHBS than in those of the normal control group (P < 0.05), while there was no statistical difference between the two syndrome types. The percentage of CD147 expression was obviously lower in DHBS than in those of CDBS and the normal control group (P < 0.05). CONCLUSIONS: Increased serum MMP-3 level of RA patients of DHBS might result in destroy of joint cartilages and sclerotin. The significant increase of MFI and decreased expression percentage of monocyte CD147 might be the results of increased disease activity of RA and monocyte migration to the synovial membrane tissue.