Na3K6(CO3)3(NO3)2X·6H2O (X = NO3, Cl, Br): Exploring High-Performance UV Birefringent Crystals Induced by Coplanar π-Conjugated CO3 and NO3 Groups

Planar π-conjugated groups, like CO3, NO3, and BO3 triangles, are ideal functional units for designing birefringent materials due to their large optical anisotropy and wide band gap. The key point for designing birefringent crystals is to select appropriate functional building blocks (FBBs) and the proper arrangement mode. It is well known that the substitution strategy has proven to be a promising and accessible approach. In this work, alkali metals were chosen to regulate and control two different π-conjugated groups, CO3 and NO3, to build new compounds with large birefringence. Subsequently, three new compounds, Na3K6(CO3)3(NO3)2X·6H2O (X = NO3, Cl, Br), were successfully synthesized using the hydrothermal method. The aliovalent substitution between the [NO3]- anionic group and halogen anions [Cl]-/[Br]- has been achieved in these compounds. Na3K6(CO3)3(NO3)2X·6H2O feature the well-coplanar CO3 and NO3 groups in their crystal structure. This coplanar arrangement mode may effectively enhance the anisotropic polarizability of Na3K6(CO3)3(NO3)2X·6H2O. And their experimental birefringence can reach 0.094-0.131 at 546 nm. Diffuse reflectance spectra demonstrate that these compounds exhibit short ultraviolet (UV) absorption edges of ∼235 nm. Meanwhile, Na3K6(CO3)3(NO3)2X·6H2O also have an easily grown capacity under facile conditions. This work not only reports three new potential UV birefringent crystals but also provides a strategy to make the π-conjugated MO3 group coplanar.

[Pelvic exenteration for late complications of radiation-induced pelvic injury: a preliminary study]

Objective: To investigate the safety and efficacy of total pelvic exenteration (TPE) for treating late complications of radiation-induced pelvic injury. Methods: This was a descriptive case series study. The inclusion criteria were as follows: (1) confirmed radiation-induced pelvic injury after radiotherapy for pelvic malignancies; (2) late complications of radiation-induced pelvic injury, such as bleeding, perforation, fistula, and obstruction, involving multiple pelvic organs; (3) TPE recommended by a multidisciplinary team; (4) patient in good preoperative condition and considered fit enough to tolerate TPE; and (5) patient extremely willing to undergo the procedure and accept the associated risks. The exclusion criteria were as follows: (1) preoperative or intraoperative diagnosis of tumor recurrence or metastasis; (2) had only undergone diversion or bypass surgery after laparoscopic exploration; and (3) incomplete medical records. Clinical and follow-up data of patients who had undergone TPE for late complications of radiation-induced pelvic injury between March 2020 and September 2022 at the Sixth Affiliated Hospital of Sun Yat-sen University were analyzed. Perioperative recovery, postoperative complications, perioperative deaths, and quality of life 1 year postoperatively were recorded. Results: The study cohort comprised 14 women, nine of whom had recto-vagino-vesical fistulas, two vesicovaginal fistulas, one ileo-vesical fistula and rectal necrosis, one ileo-vesical and rectovaginal fistulas, and one rectal ulcer and bilateral ureteral stenosis. The mean duration of surgery was 592.1±167.6 minutes and the median blood loss 550 (100-6000) mL. Ten patients underwent intestinal reconstruction, and four the Hartmann procedure. Ten patients underwent urinary reconstruction using Bricker's procedure and 7 underwent pelvic floor reconstruction. The mean postoperative hospital stay was 23.6±14.9 days. Seven patients (7/14) had serious postoperative complications (Clavien-Dindo IIIa to IVb), including surgical site infections in eight, abdominopelvic abscesses in five, pulmonary infections in five, intestinal obstruction in four, and urinary leakage in two. Empty pelvis syndrome (EPS) was diagnosed in five patients, none of whom had undergone pelvic floor reconstruction. Five of the seven patients who had not undergone pelvic floor reconstruction developed EPS, compared with none of those who had undergone pelvic floor reconstruction. One patient with EPS underwent reoperation because of a pelvic abscess, pelvic hemorrhage, and intestinal obstruction. There were no perioperative deaths. During 18.9±10.1 months of follow-up, three patients died, two of renal failure, which was a preoperative comorbidity, and one of COVID-19. The remaining patients had gradual and significant relief of symptoms during follow-up. QLQ-C30 assessment of postoperative quality of life showed gradual improvement in all functional domains and general health at 1, 3, and 6 months postoperatively (all P<0.05). Conclusions: TPE is a feasible procedure for treating late complications of radiation-induced pelvic injury combined with complex pelvic fistulas. TPE is effective in alleviating symptoms and improving quality of life. However, the indications for this procedure should be strictly controlled and the surgery carried out only by experienced surgeons.

Diagnostic value of the cerebrospinal fluid lipoarabinomannan assay for tuberculous meningitis: a systematic review and meta-analysis

Objective

This systematic review aims to evaluate the diagnostic accuracy of cerebrospinal fluid (CSF) lipoarabinomannan (LAM) assays in detecting tuberculous meningitis (TBM).

Methods

A systematic review search was conducted in PubMed and five other databases up to April 2023. Studies that evaluated the diagnostic accuracy of CSF LAM assays were included with either definitive or composite reference standard used as the preferred reference standard. The quality of the included studies was assessed using the QUADAS-2 tool. We performed a bivariate random-effects meta-analysis and calculated the summary diagnostic statistics.

Results

A total of six studies, including a sample size of 999, were included in the final analysis. The pooled sensitivity, specificity, and area under the receiver operating characteristic curve (AUC) of CSF LAM for diagnosing TBM were determined to be 0.44 (95% CI: 0.31-0.58), 0.89 (95% CI: 0.81-0.93), and 0.76 (95% CI: 0.73-0.80), respectively. Significant heterogeneity was observed in both sensitivity (Q = 73.82, p < 0.01; I2 = 86.45, 95%CI: 79.64-93.27) and specificity (Q = 95.34, p < 0.01; I2 = 89.51, 95% CI: 84.61-94.42). Regression analysis indicated that the study design (retrospective vs. prospective) was associated with the heterogeneity of pooled sensitivity and specificity (all p < 0.05).

Conclusion

Although more prospective studies are required to validate the role of the CSF LAM assay, current evidence supports that the performance of the CSF LAM assay is unsatisfactory for the TBM diagnosis. Additionally, the optimization of the CSF LAM assay (e.g., improvements in CSF collection and preparation methods) should be considered to improve its performance.

Transcription factor 21 accelerates vascular calcification in mice by activating the IL-6/STAT3 signaling pathway and the interplay between VSMCs and ECs

Vascular calcification is caused by the deposition of calcium salts in the intimal or tunica media layer of the aorta, which increases the risk of cardiovascular events and all-cause mortality. However, the mechanisms underlying vascular calcification are not fully clarified. Recently it has been shown that transcription factor 21 (TCF21) is highly expressed in human and mouse atherosclerotic plaques. In this study we investigated the role of TCF21 in vascular calcification and the underlying mechanisms. In carotid artery atherosclerotic plaques collected from 6 patients, we found that TCF21 expression was upregulated in calcific areas. We further demonstrated TCF21 expression was increased in an in vitro vascular smooth muscle cell (VSMC) osteogenesis model. TCF21 overexpression promoted osteogenic differentiation of VSMC, whereas TCF21 knockdown in VSMC attenuated the calcification. Similar results were observed in ex vivo mouse thoracic aorta rings. Previous reports showed that TCF21 bound to myocardin (MYOCD) to inhibit the transcriptional activity of serum response factor (SRF)-MYOCD complex. We found that SRF overexpression significantly attenuated TCF21-induced VSMC and aortic ring calcification. Overexpression of SRF, but not MYOCD, reversed TCF21-inhibited expression of contractile genes SMA and SM22. More importantly, under high inorganic phosphate (3 mM) condition, SRF overexpression reduced TCF21-induced expression of calcification-related genes (BMP2 and RUNX2) as well as vascular calcification. Moreover, TCF21 overexpression enhanced IL-6 expression and downstream STAT3 activation to facilitate vascular calcification. Both LPS and STAT3 could induce TCF21 expression, suggesting that the inflammation and TCF21 might form a positive feedback loop to amplify the activation of IL-6/STAT3 signaling pathway. On the other hand, TCF21 induced production of inflammatory cytokines IL-1β and IL-6 in endothelial cells (ECs) to promote VSMC osteogenesis. In EC-specific TCF21 knockout (TCF21ECKO) mice, VD3 and nicotine-induced vascular calcification was significantly reduced. Our results suggest that TCF21 aggravates vascular calcification by activating IL-6/STAT3 signaling and interplay between VSMC and EC, which provides new insights into the pathogenesis of vascular calcification. TCF21 enhances vascular calcification by activating the IL-6-STAT3 signaling pathway. TCF21 inhibition may be a new potential therapeutic strategy for the prevention and treatment of vascular calcification.

Transcriptome analysis identifies the role of Class I histone deacetylase in Alzheimer's disease

Epigenetics modification is a process that does not change the sequence of deoxyribonucleic acid (DNA) in disease progression but can alter the genetic expression of the brain in Alzheimer's disease (AD). In this study, we deployed the weighted gene co-expression network analysis (WGCNA) to explore the role of Class I histone deacetylases (HDACs) in AD, which included HDAC1, HDAC2, HDAC3, and HDAC8. The aim of the study was to find how Class I HDACs affected AD pathology by analyzing the Gene Expression Omnibus (GEO) microarray datasets GSE33000. We found that HDAC1 and HDAC8 were more highly expressed in the cortex of AD patients than in Controls, while HDAC2 and HDAC3 were lower expressed. By WGCNA analysis, we found the blue module was associated with HDAC1 and HDAC8, and the turquoise module was related to HDAC2 and HDAC3. Functional enrichment analysis revealed that the Wnt signaling pathway and synaptic plasticity played an important role in the modification of HDAC1 and HDAC8 while gap junction and cell-cell junction were involved in the regulation of HDAC2 and HDAC3 in the disease progression of AD. By Receiver Operating Characteristics (ROC) analysis, we concluded that HDAC1 might be the most probable diagnostic biomarker of Class I HDACs for AD. Our study provided a comprehensive understanding of Class I HDACs and provided new insight into the function of HDAC1 in AD disease progression.

The incremental value of CCTA-derived myocardial radiomics signature for ischemia diagnosis with reference to CT myocardial perfusion imaging

OBJECTIVES

To explore the incremental value of myocardial radiomics signature derived from static coronary computed tomography angiography (CCTA) for identifying myocardial ischemia based on stressdynamic CT myocardial perfusion imaging (CT-MPI).

METHODS

Patients who underwent CT-MPI and CCTA were retrospectively enrolled from two independent institutions, one used as training and the other as testing. Based on CT-MPI, coronary artery supplying area with relative myocardial blood flow (rMBF) value <0.8 was consideredischemia. Conventional imagingfeatures oftarget plaques which caused the most severe narrowing of the vessel included area stenosis, lesion length (LL), total plaque burden, calcification burden, non-calcification burden, high-risk plaque (HRP) score and CT fractional flow reserve (CT-FFR). Myocardial radiomics features were extracted at three vascular supply areas from CCTA images. The optimized radiomics signature was added to the conventional CCTA features to build the combined model (radiomics + conventional).

RESULTS

There were 168 vessels from 56 patients enrolled in the training set, and the testing set consisted of 135 vessels from 45 patients. From either cohort, HRP score, LL, stenosis ≥50% and CT-FFR ≤0.80 were associatedwith ischemia. The optimal myocardial radiomics signature consisted of nine features. The detection of ischemia using the combined model was significantly improved compared with conventional model in both training and testing set (AUC 0.789 vs 0.608, p < 0.001; 0.726 vs 0.637, p = 0.045).

CONCLUSIONS

Myocardial radiomics signature extracted from static CCTA combining with conventional features could provide incremental value to diagnose specific ischemia.

ADVANCES IN KNOWLEDGE

Myocardial radiomics signature extracted from CCTA may capture myocardial characteristics and provide incremental value to detect specific ischemia when combined with conventional features.

Liver X receptor agonists exert antitumor effects against hepatocellular carcinoma via inducing REPS2 expression

Recent studies show that liver X receptor (LXR) agonists exert significant antitumor effects in a variety of tumor cell lines including hepatocellular carcinoma (HCC). But the molecular mechanisms underlying LXR antitumor activity are not fully understood. In this study we investigated the effect of LXR agonist T0901317 (T317) on HCC development and its relationship with RalA binding protein 1 (RALBP1)-associated EPS domain containing 2 (REPS2)/epidermal growth factor receptor (EGFR) signaling axis. We showed that T317 (0.1-0.5 μM) dose-dependently increased REPS2 expression in normal hepatocytes (BNLCL.2 and LO2) and HCC cells (HepG2 and Huh-7). Using promoter activity assay and chromatin immunoprecipitation (CHIP) assay we demonstrated that T317 enhanced REPS2 expression at the transcriptional level via promoting the binding of LXR protein to the LXR-response element (LXRE) in the REPS2 promoter region. We showed that the inhibitory effect of T317 on the proliferation and migration of HCC cells was closely related to REPS2. Moreover, we revealed that T317 (400 nM) increased expression of REPS2 in HepG2 cells, thus inhibiting epidermal growth factor (EGF)-mediated endocytosis of EGFR as well as the downstream activation of AKT/NF-κB, p38MAPK, and ERK1/2 signaling pathways. Clinical data analysis revealed that REPS2 expression levels were inversely correlated with the development of HCC and reduced REPS2 expression associated with poor prognosis, suggesting that REPS2 might be involved in the development of HCC. In conclusion, this study provides new insights into the potential mechanisms of LXR agonist-inhibited HCC.

Intestinal dysbiosis mediates cognitive impairment via the intestine and brain NLRP3 inflammasome activation in chronic sleep deprivation

Growing evidence suggests the involvement of the microbiota-gut-brain axis in cognitive impairment induced by sleep deprivation (SD), however how the microbiota-gut-brain axis work remains elusive. Here, we discovered that chronic SD induced intestinal dysbiosis, activated NLRP3 inflammasome in the colon and brain, destructed intestinal/blood-brain barrier, and impaired cognitive function in mice. Transplantation of "SD microbiota" could almost mimic the pathological and behavioral changes caused by chronic SD. Furthermore, all the behavioral and pathological abnormalities were practically reversed in chronic sleep-deprived NLRP3^-/- mice. Regional knockdown NLRP3 expression in the gut and hippocampus, respectively. We observed that down-regulation of NLRP3 in the hippocampus inhibited neuroinflammation, and ameliorated synaptic dysfunction and cognitive impairment induced by chronic SD. More intriguingly, the down-regulation of NLRP3 in the gut protected the intestinal barrier, attenuated the levels of peripheral inflammatory factors, down-regulated the expression of NLRP3 in the brain, and improved cognitive function in chronic SD mice. Our results identified gut microbiota as a driver in chronic SD and highlighted the NLRP3 inflammasome as a key regulator within the microbiota-gut-brain axis.

Asymmetric {Dy4} Metallogrid and Double-Layered {Dy8} Cage Clusters from Carboxylic Decorated o-vanillin Schiff Bases: Syntheses, Topological Variation, and Single Molecule Magnet Behaviors

There is still great potential to be tapped for polynuclear lanthanide single molecule magnets (Ln-SMMs) in performance. Towards this goal, the exploration of polynuclear lanthanide clusters (PLnCs) with novel special...

Hypoxia-induced upregulation of matrix metalloproteinase 9 increases basement membrane degradation by downregulating collagen type IV alpha 1 chain

Hypoxia can cause basement membrane (BM) degradation in tissues. Matrix metalloproteinase 9 (MMP-9) is involved in various human cancers as well as BM degradation by downregulating type IV collagen (COL4). This study investigated the role of MMP-9 in hypoxia-mediated BM degradation in rat bone marrow based on its regulation of collagen type IV alpha 1 chain (COL4A1). Eighty male rats were randomly divided into four groups based on exposure to hypoxic conditions at a simulated altitude of 7,000 m, control (normoxia) and 3, 7, and 10 days of hypoxia exposure. BM degradation in bone marrow was determined by transmission electron microscopy. MMP-9 levels were assessed by western blot and real-time PCR, and COL4A1 levels were assessed by western blot and immunohistochemistry. Microvessels BMs in bone marrow exposed to acute hypoxia were observed by electron microscopy. MMP-9 expression increased, COL4A1 protein expression decreased, and BM degradation occurred in the 10-, 7-, and 3-day hypoxia groups compared with that in the control group (all P < 0.05). Hypoxia increased MMP-9 levels, which in turn downregulated COL4A1, thereby increasing BM degradation. MMP-9 upregulation significantly promoted BM degradation and COL4A1 downregulation. Our results suggest that MMP-9 is related to acute hypoxia-induced BM degradation in bone marrow by regulating COL4A1.

The determination and elimination of hidden inherent preference using q-ROFNs multicriteria group decision making problem

 The group decision-making problem usually involves decision makers (DMs) from different professional backgrounds, which leads to a considerable point, that it is the fact that there will be a certain difference in the professional cognition, risk preference and other hidden inherent factors of these DMs to the objective things that need to be evaluated. To improve the reasonability of decision-making, these hidden inherent preference (HIP) of DMs should be determined and eliminated prior to decision making. As a special form of fuzzy set, q-rung orthopair fuzzy numbers (q-ROFNs) is a useful tool to process uncertain information in decision making problems. Hence, under the environment of q-ROFNs, the determination of HIP based on distance from average score is proposed and a risk model is established to eliminate the HIP by analyzing the possible impact. Meanwhile, a dominant function is proposed, which extends the comparison method between q-ROFNs and an integrated decision-making method is provided. Finally, considering the application background of double carbon economy, an example by selecting the best design of electric vehicles charging station (EVCS) is conducted to illustrate the proposed method, and the feasibility and efficiency are verified.

DI-3-n-butylphthalide mitigates stress-induced cognitive deficits in mice through inhibition of NLRP3-Mediated neuroinflammation

Our previous study has demonstrated that chronic stress could cause cognitive deficits and tau pathology. However, the underlying mechanism and whether/how DI-3-n-Butylphthalide (NBP) ameliorates these effects are still unclear. Here, Wild-type mice were subjected to chronic unpredictable and mild stress (CUMS) for 8 weeks. Following the initial 4 weeks, the stressed animals were separated into susceptible (depressive) and unsusceptible (resilient) groups based on behavioral tests. Then, NBP (30 mg/kg i.g) was administered for 4 weeks. Morris water maze (MWM), Western-blot, Golgi staining, immunofluorescence staining and ELISA were used to examine behavioral, biochemical, and pathological changes. The results showed that both depressive and resilient mice displayed spatial memory deficits and an accumulation of tau in the hippocampus. Activated microglia and NLRP3 inflammasome were found after 8-week chronic stress. We also found a decreased level of postsynaptic density (PSD) related proteins (PSD93 and PSD95) and decreased the number of dendritic spines in the hippocampus. Interestingly, almost all the pathological changes in depressive and resilient mice previously mentioned could be reversed by NBP treatment. To further investigate the role of NLRP3 inflammasome in chronic stress-induced cognitive deficits, NLRP3 KO mice were also exposed to chronic stress. And these changes induced by chronic stress could not be found in NLRP3 KO mice. These results show an important role for the NLRP3/caspase-1/IL-1β axis in chronic stress-induced cognitive deficits and NBP meliorates cognitive impairments and selectively attenuates phosphorylated tau accumulation in stressed mice through regulation of NLRP3 inflammatory signaling pathway.

[Analysis on operational safety of chronic radiation intestinal injury]

Objective: To investigate the safety and efficacy of surgical treatment for chronic radiation intestinal injury. Methods: A descriptive cohort study was performed. Clinical data of 73 patients with definite radiation history and diagnosed clinically as chronic radiation intestinal injury, undergoing operation at Department of Colorectal Surgery, the Sixth Affiliated Hospital of Sun Yat-sen University from January 1, 2012 to February 28, 2019, were reviewed and analyzed retrospectively. Patients did not undergo operation or only received adhesiolysis were excluded. All the patients had preoperative examination and overall evaluation of the disease. According to severity of intestinal obstruction and patients' diet, corresponding nutritional support and conservative treatment were given. Surgical methods: The one-stage bowel resection and anastomosis was the first choice for surgical treatment of chronic radiation intestinal injury. Patients with poor nutritional condition were given enterostomy and postoperative enteral nutrition and second-stage stoma closure and intestinal anastomosis if nutritional condition improved. For those who were unable to perform stoma closure, a permanent stoma should be performed. Patients with severe abdominal adhesion which was difficult to separate, enterostomy or bypass surgery after adhesiolysis would be the surgical choice. For patients with tumor metastasis or recurrence, enterostomy or bypass surgery should be selected. Observation parameters: the overall and major (Clavien-Dindo grades III to V) postoperative complication within 30 days after surgery or during hospitalization; mortality within postoperative 30 days; postoperative hospital stay; time to postoperative recovery of enteral nutrition; time to removal of drainage tube. Results: Of the 73 patients who had been enrolled in this study, 10 were male and 63 were female with median age of 54 (range, 34-80) years. Preoperative evaluation showed that 61 patients had intestinal stenosis, 63 had intestinal obstruction, 11 had intestinal perforation, 20 had intestinal fistula, 3 had intestinal bleeding, and 6 had abdominal abscess, of whom 64(87.7%) patients had multiple complications. Tumor recurrence or metastasis was found in 15 patients. A total of 65(89.0%) patients received preoperative nutritional support, of whom 35 received total parenteral nutrition and 30 received partial parenteral nutrition. The median preoperative nutritional support duration was 8.5 (range, 6.0-16.2) days. The rate of one-stage intestine resection was 69.9% (51/73), and one-stage enterostomy was 23.3% (17/73). In the 51 patients undergoing bowel resection, the average length of resected bowel was (50.3±49.1) cm. Among the 45 patients with intestinal anastomosis, 4 underwent manual anastomosis and 41 underwent stapled anastomosis; 36 underwent side-to-side anastomosis, 5 underwent end-to-side anastomosis, and 4 underwent end-to-end anastomosis. Eighty postoperative complications occurred in 39 patients and the overall postoperative complication rate was 53.4% (39/73), including 39 moderate to severe complications (Clavien-Dindo grade III-V) in 20 patients (27.4%, 20/73) and postoperative anastomotic leakage in 2 patients (2.7%, 2/73). The mortality within postoperative 30 days was 2.7% (2/73); both patients died of abdominal infection, septic shock, and multiple organ failure caused by anastomotic leakage. The median postoperative hospital stay was 13 (11, 23) days, the postoperative enteral nutrition time was (7.2±6.9) days and the postoperative drainage tube removal time was (6.3±4.2) days. Conclusions: Surgical treatment, especially one-stage anastomosis, is safe and feasible for chronic radiation intestine injury. Defining the extent of bowel resection, rational selection of the anatomic position of the anastomosis and perioperative nutritional support treatment are the key to reduce postoperative complications.

[Staining effect of bovine incisors in vitro by tea solutions]

OBJECTIVE

To determine the optimum staining condition of tea solutions on bovine incisors in vitro, by comparing the color stability of tooth surface of different concentrations of tea solutions and methods on bovine incisors in vitro.

METHODS

Twenty bovine incisors with color surface A1 were chosen, then randomly divided into 4 groups (n=10). Group 1: soaked with 2% tea solution continuously for 6 days; group 2: soaked with 2% tea solution for 6 days, but changed fresh tea solution everyday; group 3: soaked with 1% tea solution continuously for 6 days; group 4: soaked with 1% tea solution for 6 days but fresh tea solution changed every day. After 6 days of staining, the surface color (Δ E value) of all the samples were measured with crystal eye. After brushing 30 times with toothbrushes, the color of bovine incisors were measured again. Then the samples were soaked in artificial saliva at 37 ° C, and Δ E value was measured for 14 days.

RESULTS

After staining for 6 days, the Δ E values of the 2% tea solution groups were better than those of the 1% groups (20.21 vs. 16.44, 24.09 vs. 19.22, P<0.05); the groups with the same tea solution concentration, a better result was observed for the group soaked with daily fresh tea solution than for the group that experienced continuous staining (24.09 vs. 20.21, 19.22 vs. 16.44, P<0.05). Groups 1 and 2 were selected for subsequent brushing experiments. The color of both groups became lighter after brushing, and a better result was observed for the continuous staining group than for the group stained in daily fresh solution (3.06 vs. 9.51, P<0.05). The samples with better coloring effect soaked with 2% tea solution continuously for 6 days were put into artificial saliva for 14 days. There was not any significant change in coloring at the end of the first two days (1.51 vs. 1.51, P>0.05), and the color was visibly lighter after the third day (1.51 vs. 5.89, P<0.05), and no further significant change was observed until the 14th day (5.81 vs.5.89, P>0.05), which was darker coloring than that of the pre-staining group.

CONCLUSION

Continuous staining on bovine incisors with 2% tea solution with subsequent soaking in artificial saliva resulted in consistent coloring from day 3 to day 14, and this method could be used as an ideal model for teeth staining in vitro.

A Highly Selective Fluorescent Probe for Zn2+ Based on a Rhodamine-6G dye Derivative Modified by a Furan Unit

A fluorescent probe for Zn2+ based on rhodamine-6G has been synthesised. It showed excellent fluorescent specific selectivity and high sensitivity for Zn2+ compared with other metal ions, such as Fe3+, Cr3+, Hg2+, Ag+, Ca2+, Cu2+, Pb2+, Cd2+, Ni2+, Co2+ and Mg2+, in CH3CN–phosphate buffer saline solution. The distinct colour change and the rapid emergence of fluorescence emission provided ‘naked-eye’ detection of Zn2+. The detection limit of the fluorescent probe towards Zn2+ was 1.78 μM. In addition, the fluorescence lifetime and fluorescence quantum yield were measured.

MARIS plays important roles in Arabidopsis pollen tube and root hair growth

In flowering plants, male gametes are delivered to female gametes for double fertilization through pollen tubes. Therefore, pollen tube growth is crucial for double fertilization. Despite its importance to sexual reproduction, genetic mechanisms of pollen tube growth remain poorly understood. In this study, we characterized the receptor-like cytoplasmic protein kinase (RLCK) gene, MARIS (MRI) that plays critical roles in pollen tube growth. MRI is preferentially expressed in pollen grains, pollen tubes and roots. Mutation in MRI by a Ds insertion led to a burst of pollen tubes after pollen germination. Pollen-rescue assay by pollen and pollen tube-specific expression of MRI in the mri-4 mutant showed that loss of MRI function also severely affected root hair elongation. MRI protein interacted with the protein kinase OXIDATIVE SIGNAL INDUCIBLE1 (OXI1) in the in vitro and in vivo assays, which functions in plant defence and root hair development, and was phosphorylated by OXI1 in vitro. Our results suggest that MRI plays important roles in pollen tube growth and may function in root hair elongation through interaction with OXI1.

MicroRNA expression profiling identifies miR-328 regulates cancer stem cell-like SP cells in colorectal cancer

Background:

Side population (SP) cells and their relationship to stem cell-like properties have been insufficiently studied in colorectal cancer (CRC). MicroRNAs (miRNAs) have attracted much attention but their roles in the maintenance of SP phenotype remain unclear.

Methods:

The SPs from CRC cell lines and primary cell cultures were analysed for stem cell-like properties. MiRNA microarray analysis identified miR-328 as a potential stemness miRNA of SP phenotype. The level of miR-328 expression in clinical samples and its correlation with SP fraction were determined. Gain-of-function and loss-of-function studies were performed to examine its roles in cancer stem-like SP cells. Furthermore, bioinformatics prediction and experimental validation were used to identify miR-328 target genes.

Results:

The SP cells sorted from CRC possess cancer stem cell (CSC)-like properties, including self-renewal, differentiation, resistance to chemotherapy, invasive and strong tumour formation ability. MiR-328 expression was significantly reduced in SP cells compared with Non-SP cells (P<0.05). Moreover, miR-328 expression was downregulated in CRC (n=33, P<0.05) and low miR-328 expression tend to correlate with high SP fraction (n=15, r=0.6559, P<0.05, Pearson's correlation). Functional studies indicated that miR-328 expression affects the number of SP cells. In addition, miR-328 overexpression reversed drug resistance and inhibited cell invasion of SP cells. Furthermore, luciferase reporter assay demonstrated that miR-328 directly targets ABCG2 and MMP16 and affects the levels of mRNA and protein expression in SP cells.

Conclusion:

These findings indicate that CRC contain cancer stem-like SP cells. MiR-328 has an important role in maintaining cancer stem-like SP phenotype that may be a potential target for effective CRC therapy.

[Suitable habitat of Therioaphis trifolii population on arable lands of southern Ningxia based on GIS]

Based on GIS techniques, the interpolation maps of Therioaphis trifolii population on the arable lands in Yuanzhou District of Guyuan City in different periods were overlapped with the ecological regionalization map and digital altitude map, aimed to analyze the relations of T. trifolii population density with its ecological environment and geographical distribution. In the study area, the occurrence and distribution of T. trifolii had close relations with climate, geomorphology, and altitude. The suitable habitat of T. trifolii in the District was located in the semi-arid plain area and semi-arid holly area at the altitude 1440-2000 m, while the most possible occurrence area was the semi-arid plain at the altitude 1600-1800 m. By combining the suitable habitat with the interpolation maps of T. trifolii population in different periods, the spatial dynamics of T. trifolii population in variety of ecological areas could be analyzed quantitatively.

Identification of dauricine and its metabolites in rat urine by liquid chromatography–tandem mass spectrometry

A rapid, sensitive and specific liquid chromatographic-electrospray ionization (ESI) tandem ion trap mass spectrometric method has been developed for identification of dauricine and its metabolites in rat urine. Six healthy rats were administrated a single dose (100 mg/kg) of dauricine by oral gavage. The urine were sampled from 0 to 24 h and purified by using a C18 solid-phase extraction (SPE) cartridge, then the purified urine samples were separated on a reversed-phase C18 column using methanol/2 mmol/L ammonium acetate (70:30, v/v, adjusted to pH 3.5 with formic acid) as mobile phase and detected by an on-line MS detector. Identification and structural elucidation of the metabolites were performed by comparing their changes in molecular mass (Deltam) and full scan MS(n) spectra with those of the parent drug. At least eight metabolites (such as N-demethyl, dehydrogenate, demethoxyl, hydroxyl, glucuronide conjugated and sulfate conjugated metabolites) and the parent drug were found in rat urine.

Accumulation of methylglyoxal in anaerobically grown Escherichia coli and its detoxification by expression of the Pseudomonas putida glyoxalase I gene

Anaerobic glycerol fermentation by Escherichia coli strains expressing genes from the Klebsiella pneumoniae dha regulon showed that cell growth and 1,3-propanediol (1,3-PD) production are significantly inhibited when 5 g/L or higher of glycerol is initially present. One reason for this inhibition may be methylglyoxal (MG) accumulation. Assays of both intracellular and extracellular MG levels indicated an accumulation of MG in anaerobic glycerol fermentation of transgenic E. coli. Pseudomonas putida glyoxalase I was expressed in the transgenic E. coli to enhance MG detoxification. The activity of glyoxalase I in the transgenic E. coli with the P. putida glyoxalase I under anaerobic conditions was 12-fold higher than that in the control cells. Compared to the control cells, the transgenic cells with the P. putida glyoxalase I displayed a reduction of 35-43% in intracellular MG and a decrease of 30% in extracellular MG. These decreases were statistically significant (P>94). Furthermore, the expression of the P. putida glyoxalase I in the transgenic E. coli markedly improved cell growth and resulted in a 50% increase in 1,3-PD production.

Meta-analysis of the association of platelet glycoprotein IIIa PlA1/A2 polymorphism with myocardial infarction

This meta-analysis examined all the published reports up to October 1999 that studied the association between PlA2 polymorphism of platelet glycoprotein IIIa gene and myocardial infarction. The PlA2 polymorphism was not found to be associated with an increased risk of myocardial infarction, either overall or in selected subgroups, which were patients with premature disease onset (age < or = 60 years), first acute myocardial infarction, and patients who were men, women, and exclusively Caucasian.