2,4-Dioxo-1-(prop-2-yn­yl)-1,2,3,4-tetra­hydro­pyrimidine-5-carbaldehyde

In the crystal structure of the title compound, C8H6N2O3, the mol­ecules are linked by a pairs of inter­molecular N—H⋯O hydrogen bonds, forming inversion dimers. The aldehyde group is in the same plane as the pyrimidine ring [with a maximum deviation of 0.083 (2) Å for the O atom), and the linear propargyl group [C—C—C = 178.99 (19)°] makes a dihedral angle of 74.36 (13)° with the ring

Bis(μ-3-carb­oxy-2-oxidobenzoato)-κ3O1,O 2:O 3;κ3 O 3:O1,O 2-bis­[aqua­(2,2′-bipyridine-κ2 N,N′)copper(II)]

In the centrosymmetric dinuclear complex, [Cu2(C8H4O5)2(C10H8N2)2(H2O)2], the CuII ion is coordinated by two N atoms from a bipyridine ligand, three O atoms from two 3-carb­oxy-2-oxidobenzoate dianions and the O atom of the water mol­ecule in a distorted octa­hedral geometry. The Cu—-O(H) coordination [2.931 (3) Å] is very weak. In the crystal structure, the dinuclear units are linked into a two-dimensional network parallel to (010) by O—H⋯O hydrogen bonds

Melaminium sulfate

In the title compound, C3H8N6 2+·SO4 2−, the melaminium cations and sulfate anions are inter­connected by N—H⋯N and N—H⋯O hydrogen bonds, forming a layer in the (101) plane. The layers are connected through multiple hydrogen bonds and π–π stacking inter­actions (centroid–centroid distance of about 3.4 Å)

Total Glucosides of Danggui Buxue Tang Attenuate BLM-Induced Pulmonary Fibrosis via Regulating Oxidative Stress by Inhibiting NOX4

Pulmonary fibrosis (PF) is a serious chronic lung disease with unknown pathogenesis. Researches have confirmed that oxidative stress which is regulated by NADPH oxidase-4 (NOX4), a main source of reactive oxygen species (ROS), is an important molecular mechanism underlying PF. Previous studies showed that total glucosides of Danggui Buxue Tang (DBTG), an extract from a classical traditional Chinese herbal formula, Danggui Buxue Tang (DBT), attenuated bleomycin-induced PF in rats. However, the mechanisms of DBTG are still not clear. We hypothesize that DBTG attenuates PF through regulating the level of oxidative stress by inhibiting NOX4. And we found that fibrosis indexes hydroxyproline (HYP) and type I collagen (Col-I) were lower in DBTG groups compared with the model group. In addition, the expression of transforming growth factor-β1 (TGF-β1) and expression of alpha smooth muscle actin (α-SMA) were also much more decreased than the model group. For oxidative stress indicators, DBTG blunted the decrease of superoxide dismutase (SOD) activity, total antioxidant capacity (T-AOC), and the increase in malondialdehyde (MDA), 8-iso-prostaglandin in lung homogenates. Treatment with DBTG restrained the expression of NOX4 compared to the model group. Present study confirms that DBTG inhibits BLM-induced PF by modulating the level of oxidative stress via suppressing NOX4

Astragaloside IV enhances the sensitivity of breast cancer stem cells to paclitaxel by inhibiting stemness

Background: Chemotherapy is one of the common treatments for breast cancer. The induction of cancer stem cells (CSCs) is an important reason for chemotherapy failure and breast cancer recurrence. Astragaloside IV (ASIV) is one of the effective components of the traditional Chinese medicine (TCM) Astragalus membranaceus, which can improve the sensitivity of various tumors to chemotherapy drugs. Here, we explored the sensitization effect of ASIV to chemotherapy drug paclitaxel (PTX) in breast cancer from the perspective of CSCs. Methods: The study included both in vitro and in vivo experiments. CSCs from the breast cancer cell line MCF7 with stem cell characteristics were successfully induced in vitro. Cell viability and proliferation were detected using the Cell Counting Kit-8 (CCK-8) and colony formation assays, and flow cytometry and terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) methods were performed to detect cell apoptosis. Stemness-related protein expression was determined by western blotting (WB) and immunohistochemistry (IHC). Body weight, histopathology, and visceral organ damage of mice were used to monitor drug toxicity. Results: The expression of stemness markers including Sox2, Nanog, and ALDHA1 was stronger in MCF7-CSCs than in MCF7. PTX treatment inhibited the proliferation of tumor cells by promoting cell apoptosis, whereas the stemness of breast cancer stem cells (BCSCs) resisted the effects of PTX. ASIV decreased the stemness of BCSCs, increased the sensitivity of BCSCs to PTX, and synergistically promoted PTX-induced apoptosis of breast cancer cells. Our results showed that the total cell apoptosis rate increased by about 25% after adding ASIV compared with BCSCs treated with PTX alone. The in vivo experiments demonstrated that ASIV enhanced the ability of PTX to inhibit the growth of breast cancer. WB and IHC showed that ASIV reduced the stemness of CSCs. Conclusions: In this study, the resistance of breast cancer to PTX was attributed to the existence of CSCs; ASIV weakened the resistance of MCF7-CSCs to PTX by significantly attenuating the hallmarks of breast cancer stemness and improved the efficacy of PTX. Keywords: Breast cancer; cancer stem cells (CSCs); astragaloside IV (ASIV); paclitaxel (PTX); chemotherap

Clinical efficacy of general anesthesia versus local anesthesia for percutaneous transforaminal endoscopic discectomy

ObjectiveLocal anesthesia (LA) is recommended for percutaneous transforaminal endoscopic discectomy(PTED), but satisfactory pain management is not mostly achieved. The goal of this study was to examine the clinical efficacy of PTED for lumbar disc herniation when performed under local anaesthetic vs. general anesthesia (GA).MethodsFrom August 2018 to August 2020, the clinical data of 108 patients treated with PTED were retrospectively evaluated and separated into two groups: LA and GA based on the anesthesia method. General information and clinical outcomes of patients were included. Visual analog scale (VAS) and Oswestry disability index (ODI) were recorded before operation, 1 week after operation, and 1 year after operation. In addition, VAS for back pain and leg pain on the second postoperative day were also recorded.ResultsWe divided the patients into two groups: 72 in LA and 36 in GA. There were no significant differences in gender, age, course of disease, body mass index, surgical segment, duration of operation, intraoperative bleeding, time of fluoroscopy, length of hospital stay, total hospitalization cost reoperation, surgical satisfaction, Macnab satisfaction, complications, preoperative and 1 year postoperatively VAS for back pain and leg pain and ODI, VAS for leg pain on the second day and 1 week postoperatively between the two groups (P > 0.05). VAS for back pain in GA group on the second day postoperatively, as well as the VAS for back pain and ODI at one week postoperatively, were better than those in LA group (P < 0.05). However, the total hospitalization cost in LA group was significantly lower than that in GA group (P < 0.05). Further analysis of different ages in the two groups showed that there were significant differences in the VAS for back pain on the second day postoperatively and ODI at 1 week postoperatively in the middle-aged group (45 ≤ Y ≤ 59), as well as the VAS for back pain on the second day postoperatively in the senior group (Y ≥ 60) (P < 0.05). However, there were no significant difference among other groups (P > 0.05).ConclusionLong-term outcomes were similar for both PTED under LA and GA, while GA group had better short-term outcomes, especially in middle-aged and elderly patients

Nitrogen acquisition strategy and its effects on invasiveness of a subtropical invasive plant

IntroductionPreference and plasticity in nitrogen (N) form uptake are the main strategies with which plants absorb soil N. However, little effort has been made to explore effects of N form acquisition strategies, especially the plasticity, on invasiveness of exotic plants, although many studies have determined the effects of N levels (e.g. N deposition).MethodsTo address this problem, we studied the differences in N form acquisition strategies between the invasive plant Solidago canadensis and its co-occurring native plant Artemisia lavandulaefolia, effects of soil N environments, and the relationship between N form acquisition strategy of S. canadensis and its invasiveness using a 15N-labeling technique in three habitats at four field sites.ResultsTotal biomass, root biomass, and the uptakes of soil dissolved inorganic N (DIN) per quadrat were higher for the invasive relative to the native species in all three habitats. The invader always preferred dominant soil N forms: NH4+ in habitats with NH4+ as the dominant DIN and NO3- in habitats with NO3- as the dominant DIN, while A. lavandulaefolia consistently preferred NO3- in all habitats. Plasticity in N form uptake was higher in the invasive relative to the native species, especially in the farmland. Plant N form acquisition strategy was influenced by both DIN levels and the proportions of different N forms (NO3-/NH4+) as judged by their negative effects on the proportional contributions of NH4+ to plant N (fNH4+) and the preference for NH4+ (βNH4+). In addition, total biomass was positively associated with fNH4+ or βNH4+ for S. canadensis, while negatively for A. lavandulaefolia. Interestingly, the species may prefer to absorb NH4+ when soil DIN and/or NO3-/NH4+ ratio were low, and root to shoot ratio may be affected by plant nutrient status per se, rather than by soil nutrient availability.DiscussionOur results indicate that the superior N form acquisition strategy of the invader contributes to its higher N uptake, and therefore to its invasiveness in different habitats, improving our understanding of invasiveness of exotic plants in diverse habitats in terms of utilization of different N forms

Structures and Vibrational Spectra of Adenine and Protonated Adenine

The structures and vibrational spectra of neutral and protonated adenine molecules were calculated at the B3LYP/aug-cc-pVTZ level. For neutral adenine, the N9H adenine configuration is more stable in energy of about 32.76 kJ . mol(-1) (6.28 kJ . mol(-1) by using the polarization continuous model (PCM)) than N7H adenine. Based on the potential energy distribution (PED) calculated using the scaled quantum mechanical field (SQMF) procedure, we corrected the assignments of some N9H adenine fundamental vibrations. There are five stable configurations for protonated adenine and the isomer of adenine that is protonated at the NI position is the most stable. Based on vibration analysis, we assigned the fundamental vibrations of this configuration and analyzed the Raman spectra of adenine in the HClO4 (pH=1) solution.National Natural Science Foundation of China [20573087]; National Key Basic Research Program of China [2007CB815303, 2009CB930703]; Program for New Century Excellent Talent (NCET) in Universities of Fujian Province, Chin

7-Deazaguanine modifications protect phage DNA from host restriction systems

Genome modifications are central components of the continuous arms race between viruses and their hosts. The archaeosine base (G+), which was thought to be found only in archaeal tRNAs, was recently detected in genomic DNA of Enterobacteria phage 9g and was proposed to protect phage DNA from a wide variety of restriction enzymes. In this study, we identify three additional 2′-deoxy-7-deazaguanine modifications, which are all intermediates of the same pathway, in viruses: 2′-deoxy-7-amido-7-deazaguanine (dADG), 2′-deoxy-7-cyano-7-deazaguanine (dPreQ0) and 2′-deoxy-7- aminomethyl-7-deazaguanine (dPreQ1). We identify 180 phages or archaeal viruses that encode at least one of the enzymes of this pathway with an overrepresentation (60%) of viruses potentially infecting pathogenic microbial hosts. Genetic studies with the Escherichia phage CAjan show that DpdA is essential to insert the 7-deazaguanine base in phage genomic DNA and that 2′-deoxy-7-deazaguanine modifications protect phage DNA from host restriction enzymes

Simulating the one‐dimensional structure of Titan's upper atmosphere: 2. Alternative scenarios for methane escape

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/94984/1/jgre2821.pd