The novel phosphatase NUDT5 is a critical regulator of triple-negative breast cancer growth.

BACKGROUND: The most aggressive form of breast cancer is triple-negative breast cancer (TNBC), which lacks expression of the estrogen receptor (ER) and progesterone receptor (PR), and does not have overexpression of the human epidermal growth factor receptor 2 (HER2). Treatment options for women with TNBC tumors are limited, unlike those with ER-positive tumors that can be treated with hormone therapy, or those with HER2-positive tumors that can be treated with anti-HER2 therapy. Therefore, we have sought to identify novel targeted therapies for TNBC. In this study, we investigated the potential of a novel phosphatase, NUDT5, as a potential therapeutic target for TNBC. METHODS: The mRNA expression levels of NUDT5 in breast cancers were investigated using TCGA and METABRIC (Curtis) datasets. NUDT5 ablation was achieved through siRNA targeting and NUDT5 inhibition with the small molecule inhibitor TH5427. Xenograft TNBC animal models were employed to assess the effect of NUDT5 inhibition on in vivo tumor growth. Proliferation, death, and DNA replication assays were conducted to investigate the cellular biological effects of NUDT5 loss or inhibition. The accumulation of 8-oxo-guanine (8-oxoG) and the induction of γH2AX after NUDT5 loss was determined by immunofluorescence staining. The impact of NUDT5 loss on replication fork was assessed by measuring DNA fiber length. RESULTS: In this study, we demonstrated the significant role of an overexpressed phosphatase, NUDT5, in regulating oxidative DNA damage in TNBCs. Our findings indicate that loss of NUDT5 results in suppressed growth of TNBC both in vitro and in vivo. This growth inhibition is not attributed to cell death, but rather to the suppression of proliferation. The loss or inhibition of NUDT5 led to an increase in the oxidative DNA lesion 8-oxoG, and triggered the DNA damage response in the nucleus. The interference with DNA replication ultimately inhibited proliferation. CONCLUSIONS: NUDT5 plays a crucial role in preventing oxidative DNA damage in TNBC cells. The loss or inhibition of NUDT5 significantly suppresses the growth of TNBCs. These biological and mechanistic studies provide the groundwork for future research and the potential development of NUDT5 inhibitors as a promising therapeutic approach for TNBC patients.

Role of the hydrogen sulfide-releasing donor ADT-OH in the regulation of mammal neural precursor cells.

Neural precursor cells (NPCs) generate new neurons to supplement neuronal loss as well as to repair damaged neural circuits. Therefore, NPCs have potential applications in a variety of neurological diseases, such as spinal cord injury, traumatic brain injury, and glaucoma. Specifically, improving NPCs proliferation and manipulating their differentiated cell types can be a beneficial therapy for a variety of these diseases. ADT-OH is a slow-releasing organic H2 S donor that produces a slow and continuous release of H2 S to maintain normal brain functions. In this study, we aimed to explore the effect of ADT-OH on NPCs. Our results demonstrated that ADT-OH promotes self-renewal and antiapoptosis ability of cultured NPCs. Additionally, it facilitates more NPCs to differentiate into neurons and oligodendrocytes, while inhibiting their differentiation into astrocytes. Furthermore, it enhances axonal growth. Moreover, we discovered that the mRNA and protein expression of ß-catenin, TCF7L2, c-Myc, Ngn1, and Ngn2, which are key genes that regulate NPCs self-renewal and differentiation, were increased in the presence of ADT-OH. Altogether, these results indicate that ADT-OH may be a promising drug to regulate the neurogenesis of NPCs, and needs to be studied in the future for clinical application potential.

Inhibition of PTEN activity promotes IB4-positive sensory neuronal axon growth.

Traumatic nerve injuries have become a common clinical problem, and axon regeneration is a critical process in the successful functional recovery of the injured nervous system. In this study, we found that peripheral axotomy reduces PTEN expression in adult sensory neurons; however, it did not alter the expression level of PTEN in IB4-positive sensory neurons. Additionally, our results indicate that the artificial inhibition of PTEN markedly promotes adult sensory axon regeneration, including IB4-positive neuronal axon growth. Thus, our results provide strong evidence that PTEN is a prominent repressor of adult sensory axon regeneration, especially in IB4-positive neurons.

c-Myc controls the fate of neural progenitor cells during cerebral cortex development.

The anatomical structure of the mammalian cerebral cortex is the essential foundation for its complex neural activity. This structure is developed by proliferation, differentiation, and migration of neural progenitor cells (NPCs), the fate of which is spatially and temporally regulated by the proper gene. This study was used in utero electroporation and found that the well-known oncogene c-Myc mainly promoted NPCs' proliferation and their transformation into intermediate precursor cells. Furthermore, the obtained results also showed that c-Myc blocked the differentiation of NPCs to postmitotic neurons, and the expression of telomere reverse transcriptase was controlled by c-Myc in the neocortex. These findings indicated c-Myc as a key regulator of the fate of NPCs during the development of the cerebral cortex.

Design, synthesis and antitumor evaluation of novel 5-methylpyrazolo[1,5-a]pyrimidine derivatives as potential c-Met inhibitors.

A series of novel 5-methylpyrazolo[1,5-a]pyrimidine derivatives (10a-10x) were designed, synthesized, and evaluated for their in vitro inhibitory activities against c-Met kinase and antiproliferative activities against the SH-SY5Y, MDA-MB-231, A549, and HepG2 cell lines. Most of the compounds remarkably inhibited c-Met kinase and showed moderate to good cytotoxicity and selectivity toward the four cancer cell lines. Among them, compounds 10b and 10f were the two most potent selective c-Met inhibitors with half-maximal inhibitory concentration (IC50) values of 5.17 ± 0.48 nM and 5.62 ± 0.78 nM, respectively, and suppression abilities comparable with the positive control cabozantinib. Cell proliferation assay further demonstrated that the two most promising compounds 10a and 10b also showed good cytotoxicity and selectivity toward MDA-MB-231 cells, with IC50 values of 26.67 ± 2.56 µM and 26.83 ± 2.41 µM, respectively. Compounds 10f and 10g showed cytotoxicity and selectivity toward A549 cells, with IC50 values of 20.20 ± 2.04 µM and 21.65 ± 1.58 µM, respectively. All antiproliferative activities were within the range of those of cabozantinib. Notably, these compounds presented relatively low hepatotoxicity compared with reference drugs. Moreover, the preliminary structure-activity relationship and docking studies revealed that replacement of a nitrogen-containing heterocycle on the R2 (block A) group might improve the c-Met kinase inhibitory and antiproliferative effects in MDA-MB-231 cells, whereas displacement by a substituted benzene ring, especially for the p-fluorophenyl or 4-fluoro-3-methoxyphenyl moiety, on the R2 group enhanced cytotoxicity toward A549 cells. Together, these results suggest that 10b and 10f are promising compounds and provide a basis for their development as new antitumor agents.

Regulation of adult mammalian intrinsic axonal regeneration by NF-κB/STAT3 signaling cascade.

The inflammatory response is a critical regulator for the regeneration of axon following nervous system injury. Nuclear factor-kappa B (NF-κB) is characteristically known for its ubiquitous role in the inflammatory response. However, its functional role in adult mammalian axon growth remains elusive. Here, we found that the NF-κB signaling pathway is activated in adult sensory neurons through peripheral axotomy. Furthermore, inhibition of NF-κB in peripheral sensory neurons attenuated their axon growth in vitro and in vivo. Our results also showed that NF-κB modulated axon growth by repressing the phosphorylation of STAT3. Furthermore, activation of STAT3 significantly promoted adult optic nerve regeneration. Taken together, the findings of our study indicated that NF-κB/STAT3 cascade is a critical regulator of intrinsic axon growth capability in the adult nervous system.

Calcium/calmodulin-dependent protein kinase II regulates mammalian axon growth by affecting F-actin length in growth cone.

While axon regeneration is a key determinant of functional recovery of the nervous system after injury, it is often poor in the mature nervous system. Influx of extracellular calcium (Ca2+ ) is one of the first phenomena that occur following axonal injury, and calcium/calmodulin-dependent protein kinase II (CaMKII), a target substrate for calcium ions, regulates the status of cytoskeletal proteins such as F-actin. Herein, we found that peripheral axotomy activates CaMKII in dorsal root ganglion (DRG) sensory neurons, and inhibition of CaMKII impairs axon outgrowth in both the peripheral and central nervous systems (PNS and CNS, respectively). Most importantly, we also found that the activation of CaMKII promotes PNS and CNS axon growth, and regulatory effects of CaMKII on axon growth occur via affecting the length of the F-actin. Thus, we believe our findings provide clear evidence that CaMKII is a critical modulator of mammalian axon regeneration.

6-Gingerol inhibits proliferation in gastric cancer via the STAT3 pathway in vitro.

With high incidence and mortality, gastric cancer seriously threatened human's life. It is arduous and necessary to investigate its pathogenesis and dig effective drugs. In this study, we explored the role of 6-Gingerol (GI), a natural active ingredient, in treating gastric cancer cells. MTT assay and colony formation assay were utilized to confirmed that GI can control the proliferation of gastric cancer cells, which is time and concentration-dependent to some extent. The Annexin V-FITC/PI staining results by flow cytometry reveal that GI induces the apoptosis of gastric cancer cells. And a study on further pathways by western blot shows that GI brings about cell apoptosis by inhibiting the activation of STAT3. GI therefore may be a good candidate for treating gastric cancer.

Pt-Pd Bimetal Popcorn Nanocrystals: Enhancing the Catalytic Performance by Combination Effect of Stable Multipetals Nanostructure and Highly Accessible Active Sites.

Exploration of highly efficient electrocatalysts is significantly urgent for the extensive adoption of the fuel cells. Because of their high activity and super stability, Pt-Pd bimetal nanocrystals have been widely recognized as one class of promising electrocatalysts for oxygen reduction. This article presents the synthesis of popcorn-shaped Pt-Pd bimetal nanoparticles with a wide composition range through a facile hydrothermal strategy. The hollow-centered nanoparticles are surrounded by several petals and concave surfaces. By exploring the oxygen reduction reaction on the carbon supported Pt-Pd popcorns in perchloric acid solution, it is found that compared with the commercial Pt/C catalyst the present catalysts display superior catalytic performances in aspects of catalytic activity and stability. More importantly, the Pt-Pd popcorns display minor performance degradations through prolonged potential cycling. The enhanced performances can be mainly attributed to the unique popcorn structure of the Pt-Pd components, which allows the appearance and long existence of the high active sites with more accessibility. The present work highlights the key roles of accessible high active sites in the oxygen reduction reaction, which will ultimately guide the design of highly durable Pt-Pd catalysts.

Pharmacokinetics and relative bioavailability of a generic amisulpride tablet in healthy Chinese volunteers
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OBJECTIVE: To assess and compare the pharmacokinetic properties and bioavailability of a newly developed formulation of amisulpride with those of a conventional formulation in healthy Chinese volunteers under fasting state. MATERIALS AND METHODS: A single-dose, two-sequence crossover study was designed. 20 healthy subjects (14 males and 6 females) were randomized into two groups. A single oral dose of amisulpride (200 mg) was given after an overnight fast of 12 hours. Blood samples were taken at scheduled time spots and separated by a washout period of 14 days. Plasma concentration of amisulpride was measured by high-performance liquid chromatography-fluorescence detector (HPLC-FLD) method. RESULTS: The pharmacokinetic parameters of AUC0-tlast, AUC0-∞, and Cmax for the 20 subjects after a single oral dose of the trial preparation or the reference preparation were 4,767.2 and 4,856.3 ng×h×mL-1; 4,891.7 and 5,043.2 ng×h×mL-1; 584.7 and 586.3 ng×mL-1, respectively. The relative bioavailability was 98.9 ± 14.5%. No significant difference was found among the main pharmacokinetic parameters in the two preparations by ANOVA. The 90% confidence intervals for the geometric mean ratios (test/reference) of Cmax and AUC0-tlast were 90.7 - 109.1% and 92.5 - 103.6%, respectively, meeting the predetermined criteria (80 - 125%) for bioequivalence. No serious adverse events were reported. CONCLUSION: The study demonstrated that the two preparations met the regulatory criteria for bioequivalence and both formulations were well tolerated.
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Isoliquiritigenin protects against triptolide-induced hepatotoxicity in mice through Nrf2 activation.

Isoliquiritigenin, a flavonoid found in licorice, has been considered as an antioxidive and hepato-protective agent. Recent studies have shown that a possible mechanism for triptolide-induced hepatotoxicity is related to oxidative damage induced by reactive oxygen species. This study was done to investigate the protection effect of isoliquiritigenin against triptolide-induced hepatotoxicity and the mechanism involved. An acute liver injury model was established by intraperitoneal injection of triptolide (1.0 mg · kg-1) in mice. Different doses of isoliquiritigenin (12.5, 25 and 50 mg · kg-1) were employed as protection. The activities of AST, ALT, ALP and LDH in serum and levels of GSH, GPx, SOD, CAT and MDA in liver tissue were detected. The histopathological changes of liver tissues were observed after HE staining. The protein expression of Nrf2 was detected by western blot. Pretreatment with isoliquiritigenin significantly prevented the triptolide-induced hepatotoxicity indicated by reduced activities of AST, ALT, ALP and LDH. Moreover, isoliquiritigenin pretreatment also prevented from triptolide-induced hepatotoxicity by inhibiting MDA and restoring the levels of GSH, GPx, SOD and CAT. In addition, isoliquiritigenin could attenuate histopathological changes induced by triptolide. Furthermore, the results indicated that isoliquiritigenin pretreatment caused an increase in the protein expression of Nrf2. These results indicated that isoliquiritigenin could protect against triptolide-induced hepatotoxicity via activation of the Nrf2 pathway.

G protein coupled receptor 50 promotes self-renewal and neuronal differentiation of embryonic neural progenitor cells through regulation of notch and wnt/ß-catenin signalings.

G protein-coupled receptor 50 (GPR50), a risk factor for major depressive disorder and bipolar affective disorder, is expressed in both the developmental and adult brain. However, the function of GPR50 in the brain remains unknown. We here show GPR50 is expressed by neural progenitor cells (NPCs) in the ventricular zone of embryonic brain. Knockdown of GPR50 with a small interference RNA (siRNA) decreased self-renewal and neuronal differentiation, but not glial differentiation of NPCs. Moreover, overexpression of either full-length GPR50 or the intracellular domain of GPR50, rather than the truncated GPR50 in which the intracellular domain is deleted in, increased neuronal differentiation, indicating that GPR50 promotes neuronal differentiation of NPCs in an intracellular domain-dependent manner. We further described that the transcriptional activity of the intracellular domain of notch on Hes1 gene was repressed by overexpression of GPR50. In addition, decreased levels of transcription factor 7-like 2 (TCF7L2) mRNA was observed in GPR50 siRNA-transfected NPCs, suggesting that knockdown of GPR50 impairs wnt/ß-catenin signaling. Moreover, the mRNA levels of neurogenin (Ngn) 1, Ngn2 and cyclin D1, the target genes of notch and wnt/ß-catenin signalings, in NPCs were reduced by knockdown of GPR50. Therefore, GPR50 promotes self-renewal and neuronal differentiation of NPCs possibly through regulation of notch and wnt/ß-catenin signalings.

Genetic diversity and recombination analysis of grapevine leafroll-associated virus 1 from China.

Grapevine leafroll-associated virus 1 (GLRaV-1) is one of the causal agents of grapevine leafroll disease (GLD). To investigate the prevalence and genetic variation of GLRaV-1 in China, 132 grapevine samples from 14 Chinese provinces and regions were tested using reverse transcription PCR (RT-PCR) and reverse transcription nested PCR (RT-nPCR). The samples included symptomatic and asymptomatic cultivars, and 36.4% of them tested positive for GLRaV-1. 'Beida' samples, previously identified as virus-free rootstocks, were also found to be infected with GLRaV-1 with an incidence of 40 . GLRaV-1 coat protein (CP) genes and heat-shock protein 70 (HSP70) genes from 43 GLRaV-1 isolates were selected and sequenced. Phylogenetic analysis of global CP and HSP70 gene sequences showed that all variants belonged to eight and seven groups, respectively. For CP gene sequence variants, group 4 was a new group that included only Chinese isolates. The results also showed that natural selection, rather than random processes, led to the evolution of variants belonging to CP gene sequence variants in group 2 and group 8. Furthermore, three new recombination events were identified in the GLRaV-1 CP gene population. This is the first report on the genetic variation of GLRaV-1 isolates in China, and this study will benefit grape clean-plant programs in China.

An Improved Helferich Method for the α/ß-Stereoselective Synthesis of 4-Methylumbelliferyl Glycosides for the Detection of Microorganisms.

An improved Helferich method is presented. It involves the glycosylation of 4-methyl-umbelliferone with glycosyl acetates in the presence of boron trifluoride etherate combined with triethylamine, pyridine, or 4-dimethylaminopyridine under mild conditions, followed by deprotection to give fluorogenic 4-methylumbelliferyl glycoside substrates. Due to the use of base, the glycosylation reaction proceeds more easily, is uncommonly α- or ß-stereoselective, and affords the corresponding products in moderate to excellent yields (51%-94%) under appropriate conditions.

Therapeutic efficacy of recombinant human growth hormone in children with different etiologies of dwarfism from a pharmacoeconomic point of view.

Treatment outcomes for different causes of childhood dwarfism vary widely, and there are no studies on the economic burden of treatment in relation to outcomes. This paper compared the efficacy and healthcare costs per unit height of recombinant human growth hormone (rhGH) for the treatment of growth hormone deficiency (GHD) and idiopathic short stature (ISS) with a view to providing a more cost-effective treatment option for children. We retrospectively analyzed 117 cases (66 cases of GHD and 51 cases of ISS) of short-stature children who first visited Weifang People's Hospital between 2019.1 and 2022.1 and were treated with rhGH for 1 to 3 years to track the treatment effect and statistically analyzed by using paired t tests, non-parametric tests, and chi-square tests, to evaluate the efficacy of rhGH treatment for GHD and ISS children and the medicinal cost. The annual growth velocity (GV) of children with GHD and ISS increased the fastest during 3 to 6 months after treatment and then gradually slowed down. The GV of the GHD group was higher than that of the ISS group from 0 to 36 months after treatment (P < .05 at 3, 6, 9, and 12 months); the height standard deviation scores (HtSDS) of the children in the GHD and ISS groups increased gradually with the increase of the treatment time, and the changes in the height standard deviation scores (ΔHtSDS) of the GHD group were more significant than those of the ISS group (P < .05 at 3, 6, 9, and 12 months). (2) The medical costs in the pubertal group for a 1-cm increase in height were higher than those of children in the pre-pubertal group at the same stage (3 to 24 months P < .05). The longer the treatment time within the same group, the higher the medical cost of increasing 1cm height. RhGH is effective in treating children with dwarfism to promote height growth, and the effect on children with GHD is better than that of children with ISS; the earlier the treatment time, the lower the medical cost and the higher the comprehensive benefit.

New steroidal saponins from the aerial parts of Paris polyphylla var. yunnanensis and their effects on blood coagulation.

Five new steroidal saponins, paripolins D-H (1-5), and 6 known compounds (6-11) were isolated from the aerial parts of Paris polyphylla var. yunnanensis. The structures of 1-5 were determined using spectroscopic analyses in conjunction with acid hydrolysis. It is for the first time to report the 12-hydroxysteroidal saponins from the genus Paris. The effect of all isolated compounds on blood coagulation was determined in vitro using the plasma recalcification time method. Compounds 1 and 2 showed potent procoagulant activity, and 5-11 exhibited significant anticoagulant activity.

Bearing Capacity and Mechanism of the H-V Geogrid-Reinforced Foundation.

A series of model tests were conducted to investigate the bearing capacity and reinforced mechanism of a horizontal-vertical (H-V) geogrid-reinforced foundation. The bearing capacities of the unreinforced foundation, the conventional geogrid, and the H-V geogrid-reinforced foundation were compared. The parameters, including the length of the H-V geogrid, the vertical geogrid height, the depth of the top layer, and the number of H-V geogrid layers, are discussed. Through experiments, it was found that the optimal length of H-V geogrid is around 4B, the optimal vertical geogrid height is approximately 0.6B, and the optimal depth of the top H-V geogrid layer is between 0.33B and 1B. The optimal number of H-V geogrid layers is 2. The result also indicates that the bearing capacity of H-V geogrid is almost 1.7 times greater than that of conventional geogrid. Additionally, the maximum top subsidence of H-V geogrid-reinforced foundation decreased by 13.63% compared to that of conventional geogrid-reinforced foundation. Under the same settlement, the bearing capacity ratio of two H-V geogrid-reinforced foundation layers is 75.28% higher than that of one layer. The results also demonstrate that the vertical elements of H-V geogrid interlock the sand from being displaced under the applied load and redistribute the surcharge over a wider area, thereby increasing the shear strength and improving the bearing capacity of an H-V geogrid-reinforced foundation.

Phosphoserine-loaded chitosan membranes promote bone regeneration by activating endogenous stem cells.

Bone defects that result from trauma, infection, surgery, or congenital malformation can severely affect the quality of life. To address this clinical problem, a phosphoserine-loaded chitosan membrane that consists of chitosan membranes serving as the scaffold support to accommodate endogenous stem cells and phosphoserine is synthesized. The introduction of phosphoserine greatly improves the osteogenic effect of the chitosan membranes via mutual crosslinking using a crosslinker (EDC, 1-ethyl-3-(3-dimethyl aminopropyl)-carbodiimide). The morphology of PS-CS membranes was shown by scanning electron microscopy (SEM) to have an interconnected porous structure. The incorporation of phosphoserine into chitosan membranes was confirmed by energy dispersive spectrum (EDS), Fourier Transforms Infrared (FTIR), and X-ray diffraction (XRD) spectrum. The CCK8 assay and Live/Dead staining, Hemolysis analysis, and cell adhesion assay demonstrated that PS-CS membranes had good biocompatibility. The osteogenesis-related gene expression of BMSCs was higher in PS-CS membranes than in CS membranes, which was verified by alkaline phosphatase (ALP) activity, immunofluorescence staining, and real-time quantitative PCR (RT-qPCR). Furthermore, micro-CT and histological analysis of rat cranial bone defect demonstrated that PS-CS membranes dramatically stimulated bone regeneration in vivo. Moreover, H&E staining of the main organs (heart, liver, spleen, lung, or kidney) showed no obvious histological abnormalities, revealing that PS-CS membranes were no additional systemic toxicity in vivo. Collectively, PS-CS membranes may be a promising candidate for bone tissue engineering.

Gut microbiota and their metabolite profiles following peripheral nerve xenotransplantation.

Background: Intestinal pathogens are associated with xenotransplantation tolerance and rejection. However, changes in the gut microbiota in patients who have undergone peripheral nerve xenotransplantation and their association with immune rejection have not yet been reported. Objective: We aimed to explore intestinal microbes and their metabolites at different time points after peripheral nerve transplantation to provide new insight into improving transplant tolerance. Methods: A peripheral nerve xenotransplantation model was constructed by suturing the segmented nerves of Sprague Dawley rats to those of C57 male mice using xenotransplantation nerve bridging. Fecal samples and intestinal contents were collected at three time points: before surgery (Pre group; n = 10), 1 month after transplantation (Pos1 m group; n = 10), and 3 months after transplantation (Pos3 m group; n = 10) for 16S DNA sequencing and nontargeted metabolome detection. Results: Alpha diversity results suggested that species diversity was significantly downregulated after peripheral nerve xenotransplantation. There were six gut flora genera with significantly different expression levels after xenotransplantation: four were downregulated and two were upregulated. A comparison of the Pre vs. Pos1 m groups and the Pos1 m vs. Pos3 m groups revealed that the most significant differentially expressed Kyoto Encyclopedia of Genes and Genomes metabolite pathways were involved in phenylalanine, tyrosine, and tryptophan biosynthesis, as well as histidine metabolism. Metabolites with a strong relationship to the differentially expressed microbial flora were identified. Conclusion: Our study found lower gut microbiome diversity, with increased short-chain fatty acid (SCFA)-producing and sulfate-reducing bacteria at 1 month post peripheral nerve xenotransplantation, and these were decreased at 3 months post-transplantation. The identification of specific bacterial metabolites is essential for recognizing potential diagnostic markers of xenotransplantation rejection or characterizing therapeutic targets to prevent post-transplant infection.