Design, synthesis, antibacterial evaluation of isopropylamine linked with different substituted phenol and piperazine novel derivatives

BACKGROUND

Xanthomonas oryzae pv. oryzae (Xoo) is often considered one of the most destructive bacterial pathogens causing bacterial leaf blight (BLB), resulting in significant yield and cost losses in rice. In this study, a series of novel derivatives containing the isopropanolamine moiety linked to various substituted phenols and piperazines were designed, synthesized and screened.

RESULTS

Antibacterial activity results showed that most compounds had good inhibitory effects on Xoo, among which compound W2 (EC50  = 2.74 μg mL-1 ) exhibited the most excellent inhibitory activity, and W2 also had a certain curative effect (35.89%) on rice compared to thiodiazole copper (TC) (21.57%). Scanning electron microscopy (SEM) results indicated that compound W2 could cause rupture of the Xoo cell membrane. Subsequently, proteomics and quantitative real-time polymerase chain reaction revealed that compound W2 affected the physiological processes of Xoo and may exert antibacterial activity by targeting the two-component system pathway. Interestingly, W2 upregulated Xoo's methyltransferase to impact on its pathogenicity.

CONCLUSION

The present study offers a promising phenolic-piperazine-sopropanolamine compound as an innovative antibacterial strategy by specifically targeting the two-component system pathway and inducing upregulation of methyltransferase to effectively impact Xoo's pathogenicity. © 2024 Society of Chemical Industry.

Novel 2-Amino-1,4-Naphthoquinone Derivatives Induce A549 Cell Death through Autophagy

A series of 1,4-naphthoquinone derivatives containing were synthesized as anti-cancer agents and the crystal structure of compound 5a was confirmed by X-ray diffraction. In addition, the inhibitory activities against four cancer cell lines (HepG2, A549, K562, and PC-3) were tested, respectively, and compound 5i showed significant cytotoxicity on the A549 cell line with the IC₅₀ of 6.15 μM. Surprisingly, in the following preliminary biological experiments, we found that compound 5i induced autophagy by promoting the recycling of EGFR and signal transduction in the A549 cell, resulting in the activation of the EGFR signal pathway. The potential binding pattern between compound 5i and EGFR tyrosine kinase (PDB ID: 1M17) was also identified by molecular docking. Our research paves the way for further studies and the development of novel and powerful anti-cancer drugs.

Signaling molecule glutamic acid initiates the expression of genes related to methylglyoxal scavenging and osmoregulation systems in maize seedlings

Glutamic acid (Glu) is not only a protein amino acid, but also a signaling molecule, which takes part in various physiological processes in plants. Our previous study found that root-irrigation with Glu could improve the heat tolerance of maize seedlings by plant Glu receptor-like channels-mediated calcium signaling (Protoplasma, 2019; 256:1165-1169), but its molecular mechanism remains unclear. In this study, based on the our previous work, the maize seedlings were treated with 1 mM Glu prior to be exposed to heat stress (HS), and then the expression of genes related to related to methylglyoxal (MG)-scavenging and osmoregulation systems was quantified. The results showed that Glu treatment up-regulated the gene expression of Zea mays aldo-keto reductase (ZmAKR) under both non-HS and HS conditions. Also, the gene expression of Zea mays alkenal/alkenone reductase (ZmAAR), glyoxalase II (ZmGly II), pyrroline-5-carboxylate synthase (ZmP5CS), betaine dehydrogenase (ZmBADH), and trehalase (ZmTRE) was up-regualted by exogenous Glu treatment under HS conditions. These data imply that signaling molecule Glu initiated the expression of genes related to MG-scavenging and osmoregulation systems in maize seedlings, further supporting the fact that Glu-enhanced heat tolerance in plants.

Involvement of osmoregulation, glyoxalase, and non-glyoxalase systems in signaling molecule glutamic acid-boosted thermotolerance in maize seedlings

Glutamic acid (Glu) is not only an important protein building block, but also a signaling molecule in plants. However, the Glu-boosted thermotolerance and its underlying mechanisms in plants still remain unclear. In this study, the maize seedlings were irrigated with Glu solution prior to exposure to heat stress (HS), the seedlings' thermotolerance as well as osmoregulation, glyoxalase, and non-glyoxalase systems were evaluated. The results manifested that the seedling survival and tissue vitality after HS were boosted by Glu, while membrane damage was reduced in comparison with the control seedlings without Glu treatment, indicating Glu boosted the thermotolerance of maize seedlings. Additionally, root-irrigation with Glu increased its endogenous level, reinforced osmoregulation system (i.e., an increase in the levels of proline, glycine betaine, trehalose, and total soluble sugar, as well as the activities of pyrroline-5-carboxylate synthase, betaine dehydrogenase, and trehalose-5-phosphate phosphatase) in maize seedlings under non-HS and HS conditions compared with the control. Also, Glu treatment heightened endogenous methylglyoxal level and the activities of glyoxalase system (glyoxalase I, glyoxalase II, and glyoxalase III) and non-glyoxalase system (methylglyoxal reductase, lactate dehydrogenase, aldo-ketoreductase, and alkenal/alkenone reductase) in maize seedlings under non-HS and HS conditions as compared to the control. These data hint that osmoregulation, glyoxalase, and non-glyoxalase systems are involved in signaling molecule Glu-boosted thermotolerance of maize seedlings.

[New diagnostic classification of cheilitis and its clinical diagnostic pathway]

Cheilitis is a general term for various types of inflammatory diseases that occur on the lips. The etiology differs and the clinical manifestations and pathological features overlap, leading to difficulties in clinical diagnosis. Reasonable classification is conducive to the diagnosis of cheilitis. However, its classification is difficult because of its cha-racteristics. At present, scholars have proposed two different classification schemes, but a unified classification standard has not yet been established. We classified cheilitis based on its etiology, clinical manifestations, pathological characteristics, and relationship with systemic and special diseases on the basis of special medical reports and by combining clinical practice experience and summarizing previous cheilitis diagnosis and treatment literature. In accordance with this classification method, we proposed suggestions for the clinical diagnosis of cheilitis to provide a reference for the clinical diagnosis and treatment of complex cheilitis.

[Risk factors and prognosis of bronchopulmonary dysplasia associated pulmonary hypertension in preterm infants]

Objective: To analyze clinical features, prognosis and risk factors of bronchopulmonary dysplasia (BPD) associated pulmonary hypertension (PH). Methods: Clinical data of 338 infants with BPD were collected from the neonatal intensive care unit (NICU) in Shenzhen Maternity and Child Healthcare Hospital, Southern Medical University between January 2016 and December 2018. These infants were divided into PH group and non-PH group. The clinical features and prognosis were compared between these two groups by Chi-square test or nonparametric test. Risk factors for BPD-PH were analyzed with binary logistic regression model. Results: Among the 338 BPD infants, 314 had no PH (92.9%) and 24 had PH (7.1%), with an average gestational age of (27.1±1.8) weeks, and 206 were males and 132 females.PH infants had younger gestational age ((26.4±2.1) vs. (27.2±1.7) weeks, t=2.201, P=0.028) and lower birth weight ((798±255) vs. (1 003±240) g, t=4.030, P<0.01), compared to non-PH infants. Besides, duration of mechanical ventilation and non-invasive positive pressure ventilation were higher in PH group than that in non-PH group (14.3 (2.1, 43.7) vs. 0.5 (0, 4.7) d, Z=-4.553, P<0.01; 30.0 (22.5, 64.2) vs. 15.0 (7.0, 26.0) d, Z=-4.838, P<0.01). The proportions of maternal hypertension, small for gestational age (SGA), late onset sepsis, ventilator associated pneumonia, hemodynamically significant patent ductus arteriosus (hsPDA), patent ductus arteriosus (PDA) requiring ligation, severe BPD and severe extrauterine growth retardation (EUGR) were higher in PH group than those in non-PH group ((20.8% (5/24) vs. 6.4% (20/314), 33.3% (8/24) vs. 7.6% (24/314), 54.2% (13/24) vs. 7.3% (23/314), 25.0% (6/24) vs. 6.1% (19/314), 75.0% (18/24) vs. 39.2% (123/314), 45.8% (11/24) vs. 1.9% (6/314), 66.7% (16/24) vs. 7.3% (23/314), 75.0% (18/24) vs. 45.5% (143/314), all P<0.05). Multivariate logistic regression analysis showed that maternal hypertension (OR=12.950, 95%CI: 1.740-96.385), severe bronchopulmonary dysplasia (OR=10.160, 95%CI: 2.725-37.884), SGA (OR=4.992, 95%CI: 1.432-16.920), PDA requiring ligation (OR=19.802, 95%CI: 3.297-118.921), severe EUGR (OR=20.316, 95%CI: 2.221-185.853) were independent risk factors of BPD associated PH. In the 24 infants with PH, all 7 mild PH infants and 8 moderate PH infants survived, while 4 out of 9 severe PH infants died. Among the survivors, the longest duration of oxygen therapy was up to the corrected gestational age of 1 year and 2 months. Conclusions: PH is a severe complication of BPD, and associated with higher mortality and poor prognosis. Echocardiography screening and regular post-discharge follow up are recommended for BPD infants with risk factors of PH.

Interplay between hydrogen sulfide and methylglyoxal initiates thermotolerance in maize seedlings by modulating reactive oxidative species and osmolyte metabolism

Hydrogen sulfide (H₂S) and methylglyoxal (MG) were supposed to be novel signaling molecules in plants. However, whether interplay between H₂S and MG can initiate thermotolerance in maize seedlings and in relation to metabolism of reactive oxygen species (ROS) and osmolytes is little known. In this study, watering with MG and NaHS (H₂S donor) alone or in combination elevated survival and tissue vigor of maize seedlings under heat stress and coped with an increase in the biomembrane injury (as indicated in membrane lipid peroxidation and electrolyte leakage). The above-mentioned effects were separately weakened by MG scavengers (N-acetyl cysteine: NAC; aminoguanidine: AG) and H₂S inhibitor (DL-propargylglycine, PAG) and scavenger (hypotaurine, HT). These suggested that the interplay between H₂S and MG initiated the thermotolerance in maize seedlings. The further data indicated that, under non-heat stress and heat stress conditions, MG and NaHS alone or in combination modulated ROS metabolism by regulating the activities of antioxidant enzymes (catalase, ascorbate peroxidase, guaiacol peroxidase, glutathione reductase, monodehydroascorbate reductase, and dehydroascorbate reductase) and the contents of non-enzymatic antioxidants (ascorbic acid, glutathione, flavonoids, and carotenoids) in maize seedlings. In addition, MG and NaHS alone or in combination also separately modulated the metabolism of osmolytes (proline, trehalose, glycine betaine, and total soluble sugar), H₂S (L-cysteine desulfhydrase and O-acetylserine (thione) lyase), and MG (glyoxalase I, glyoxalase II, and MG reductase). These physiological effects also were separately impaired by NAC, AG, PAG, and HT. The current data illustrated that the interplay between H₂S and MG initiated the thermotolerance in maize seedlings by modulating ROS, osmolyte, H₂S, and MG metabolism.

Signaling Role of Glutamate in Plants

It is well known that glutamate (Glu), a neurotransmitter in human body, is a protein amino acid. It plays a very important role in plant growth and development. Nowadays, Glu has been found to emerge as signaling role. Under normal conditions, Glu takes part in seed germination, root architecture, pollen germination, and pollen tube growth. Under stress conditions, Glu participates in wound response, pathogen resistance, response and adaptation to abiotic stress (such as salt, cold, heat, and drought), and local stimulation (abiotic or biotic stress)-triggered long distance signaling transduction. In this review, in the light of the current opinion on Glu signaling in plants, the following knowledge was updated and discussed. 1) Glu metabolism; 2) signaling role of Glu in plant growth, development, and response and adaptation to environmental stress; as well as 3) the underlying research directions in the future. The purpose of this review was to look forward to inspiring the rapid development of Glu signaling research in plant biology, particularly in the field of stress biology of plants.

Glutamate signaling enhances the heat tolerance of maize seedlings by plant glutamate receptor-like channels-mediated calcium signaling

Glutamate (Glu), a neurotransmitter in animal, is a novel signaling molecule in plants, which takes part in cellular metabolism, seed germination, plant growth, development, and long-distance information transfer. However, whether Glu can enhance the heat tolerance in maize seedlings and its relation to calcium signaling is still elusive. In this study, maize seedlings were pretreated with Glu and then exposed to heat stress. The results showed that Glu pretreatment enhanced the survival percentage of maize seedlings under heat tolerance, indicating that Glu could increase the heat tolerance of maize seedlings. The Glu-induced heat tolerance was weakened by exogenous calcium chloride, plasma membrane Ca²⁺ channel blocker (LaCl₃), Ca²⁺ chelator (ethylene glycol-bis(b-aminoethylether)-N,N, N΄,N΄-tetraacetic acid), calmodulin antagonists (trifluoperazine and chlopromazine), and plant glutamate receptor-like antagonists (MgCl₂ and 6,7-dinitroquinoxaline- 2,3-(1H,4H)- dione). These findings for the first time reported that Glu could increase the heat tolerance of maize seedlings by plant glutamate receptor-like channels-mediated calcium signaling.

Methylglyoxal triggers the heat tolerance in maize seedlings by driving AsA-GSH cycle and reactive oxygen species-/methylglyoxal-scavenging system

Traditionally, methylglyoxal (MG) was looked upon as a toxic byproduct of cellular metabolism. Nowadays, MG has been found to be a novel signaling molecule. However, whether MG can trigger the heat tolerance in maize seedlings and the underlying mechanisms is still elusive. In this study, the maize seedlings irrigated with MG increased the survival percentage of seedlings under heat stress (HS), remitted a decrease in tissue vitality and an increase in electrolyte leakage, and reduced membrane lipid peroxidation, implying MG could trigger the heat tolerance of maize seedlings. The further experiments showed that MG drove the ascorbic acid (AsA)-glutathione (GSH) cycle by activating enzymes (glutathione reductase, monodehydroascorbate reductase, dehydroascorbate reductase, and ascorbate peroxidase) and increasing the contents of antioxidants (AsA and GSH) and the ratio of GSH/(GSH + oxidized glutathione) and AsA/(AsA + dehydroascorbate) under both non-HS and HS. Also, the reactive oxygen species (ROS)-scavenger system (catalase, guaiacol peroxidase, carotenoid, total phenols, and flavonoids) and MG-scavenger system (glyoxalase I and glyoxalas II) also were up-regulated in maize seedlings pretreated with MG under non-HS and HS. This work for the first time reported that MG could trigger the heat tolerance of maize seedlings by driving the AsA-GSH cycle and ROS-/MG-scavenging system.

[Clinicopathologic features and prognosis of adenoid cystic carcinoma of external auditory meatus]

Objective: To investigate clinicopathologic features and prognosis of adenoid cystic carcinoma (ACC) involving external auditory meatus. Methods: The clinical presentation and follow-up data of 63 patients with ACC of external auditory canal were collected from January 2006 to February 2017 at PLA General Hospital and Hainan Branch of PLA General Hospital. The clinicopathologic features and prognostic factors of external auditory canal ACC were analyzed. Results: (1) There were 28 males and 35 females and the average age of the first diagnosis was 48.9 years (22-81 years). The tumors showed cribriform pattern in 35 cases (15 cases of late stage), tubular pattern in 14 cases (8 cases of late stage), and solid pattern in 14 cases (9 cases of late stage). Cases with solid pattern was relatively more frequent than that of cribriform pattern and tubular pattern, but the difference was not statistically significant (P>0.05). (2) The average follow-up time was 62.4 months (2-228 months) in the 57 available cases. Among the 33 cases with recurrence, 18 cases had local recurrence and 15 cases had distant metastasis. The mean recurrence time was 40.6 months (2-204 months). Nine patients died of ACC: 2 cases in early stage (died at 48 and 102 months after the first treatment), 7 cases in late stage and 57 with (died at 9, 30, 32, 60, 72, 94 and 228 months). (3) Among the 37 patients with perineural invasion, there were 21 cases of cribriform pattern, 4 cases of tubular pattern and 12 cases of solid pattern; the number of cases in early stage and late stage were 15 and 22, respectively; and the differences were statistically significant (P<0.05). In addition, 31 cases had otalgia among the 37 patients with perineural invasion, where differences were not significant (P>0.05). (4) Thirty of 45 cases with tumor resection or partial resection of temporal bone had recurrence, whereas 3 of 12 cases of tumor combined with superficial lobectomy of parotid gland had recurrence. The difference was statistically significant (P<0.05). Postoperative adjuvant radiotherapy was given in 19 cases, including 7 cases of early stage (2 cases of recurrence), and 12 cases of late stage (8 cases of recurrence), among which there was no significant difference (P>0.05). Conclusions: ACC occurring in external auditory canal frequently recurs. Superficial parotid lobectomy at the first operation is necessary to prevent tumor recurrence. Postoperative adjuvant radiotherapy has certain curative effect on patients with early stage tumor, but it does not affect the recurrence rate. Patients at late stage are more prone to perineural invasion than those in early stage. In addition, cribriform and solid patterns are more common that tubular pattern, and there is no significant correlation between perineural invasion and otalgia.

[Clinicopathologic characterisitics of pancreatic acinar cell carcinomas]

Objective: To investigate clinical, pathological and immunohistochemical features of pancreatic acinar cell carcinoma. Methods: A retrospective review of surgical and pathological databases between 2011 and 2016 at PLA General Hospital was collected and 14 cases of acinar cell carcinoma (ACC) of the pancreas were identified. EnVision immunohistochemistry was used to detect the expression of Trypsin, bcl-10 and cytokeratin(CK) proteins. Results: The patients included nine cases of pure ACC, 3 cases of mixed acinar ductal carcinoma, 1 case of mixed acinar-neuroendocrine carcinoma and acinar-ductal-neuroendocrine carcinoma, respectively. Tumors involved different anatomic locations of the pancreas, including eight involving the head of pancreas, four in the body and tail, one in the uncinate process and one in a heterotopic pancreas. Two patients had lymph node and liver metastases before surgery. Microscopically, the tumor was hypercellular with less fibroblastic proliferation and tumor cells arranged in acinar or solid pattern. The well differentiated tumor cells showed eosinophilic, granular cytoplasm with single prominent nucleoli, while the poorly differentiated tumor cells tended to grow in solid sheets. Immunohistochemically, the tumor cells were positive for pan-cytokeratin (14/14), Trypsin (12/14) and bcl-10 (11/14). Stains for CK7 and CK19 were negative (11/14 and 3/4). According to the pTNM staging, there were 7 cases at stageⅠ, 3 at stage ⅡA, 3 at stage Ⅲ and 1 at stage Ⅳ. With average postoperative follow-up of 6-58 months, the median disease-free survival time was 16 months. Conclusions: Pancreatic acinar cell carcinoma is a rare and relatively indolent malignant tumor with characteristic histopathological and immunohistochemical features. Accurate pathological diagnosis plays an important role in patients' treatment and evaluation of prognosis.

Effect of atracylodes rhizome polysaccharide in rats with adenine-induced chronic renal failure

The aim of the study was to elucidate the therapeutic effects of Atracylodes rhizome polysaccharide on adenine-induced chronic renal failure in rats. Fifty male Sprague Dawley rats were selected and randomly divided in to 5 groups (n=10 rats per group): The normal control group, the chronic renal failure pathological control group, the dexamethasone treatment group and two Atracylodes rhizome polysaccharide treatment groups, treated with two different concentrations of the polysaccharide, the Atracylodes rhizome polysaccharide high group and the Atracylodes rhizome polysaccharide low group. All the rats, except those in the normal control group were fed adenine-enriched diets, containing 10 g adenine per kg food for 3 weeks. After being fed with adenine, the dexamethasone treatment group, Atracylodes rhizome polysaccharide high group and Atracylodes rhizome polysaccharide low group rats were administered the drug orally for 2 weeks. On day 35, the kidney coefficient of the rats and the serum levels of creatinine, blood urea nitrogen, total protein and hemalbumin were determined. Subsequent to experimentation on a model of chronic renal failure in rats, the preparation was proven to be able to reduce serum levels of creatinine, blood urea nitrogen and hemalbumin levels (P<0.05) and improve renal function. Atracylodes rhizome polysaccharide had reversed the majority of the indices of chronic renal failure in rats.

Effect of trapped energetic particles on the resistive wall mode

A stability analysis for the resistive wall mode is studied in the presence of trapped energetic particles (EPs). When the EPs' beta exceeds a critical value, a fishbonelike bursting mode (FLM) with an external kink eigenstructure can exist. This offers the first analytic interpretation of the experimental observations [Phys. Rev. Lett. 103, 045001 (2009)]. The mode-particle resonances for the FLM and the q=1 fishbone occur in different regimes of the precession frequency of EPs. In certain ranges of the plasma rotation speed and the EPs' beta, a mode conversion can occur between the resistive wall mode and FLM.

[Development of a new HPLC technique for analyzing monosaccharide composition and its application in the quality control of Silybum marianum polysaccharide]

A new HPLC-UV technique for the separation and analysis of 10 monosaccharides achieved within 13.5 min using 1-phenyl-3-methyl-5-pyrazolone (PMP) as the labelling molecule of the reductive monosaccharides has been established by combining common high performance liquid chromatography-UV and C18 column. The established technique was applied to the quantification of the monosaccharide components in extract of Silybum marianum. The results showed that the tested 10 monosaccharides as PMP derivatives were baseline separated under the HPLC conditions proposed. It was confirmed that Silybum marianum extract was composed of mannose, rhamnose, glucuronic acid, galacturonic acid, glucose, xylose, galactose and arabinose with the molar ratio of 0.66:0.84:0.58:1.0:1.6:0.69:2.7:4.8. Quantitative recoveries of the compositional monosaccharides separated from the extract were in the range of 92.4%-104.0%, and the RSD values fell within 0.68%-3.81%. The results demonstrated that the proposed HPLC method was simple, rapid, convenient, and precise, and it was applicable to the analysis of the compositional monosaccharides of Silybum marianum extract.

Analysis of expressed sequence tags from skeletal muscle-specific cDNA library of Chinese native Xiang pig

A Longissimus Dorsi muscle cDNA library of Xiang Pig was constructed, and 131 randomly isolated clones were sequenced in this study. The results of bioinformatics analysis showed that 131 ESTs represented 109 unique clones sequences, of which 99 showed homology to previously identified genes in humans or other mammals, 3 matched other uncharacterized expressed sequence tags (ESTs), and 7 showed no significant matches to sequences already present in DNA databases. No protein matches were found for 10 ESTs. Functional analysis of the ESTs showed that a considerable proportion of them encoded proteins involved in gene/protein expression (45.46%). Other classes included genes involved in metabolism (10.10%), cell structure/motility (10.10%), cell/organism defense (5.05%), cell signaling/communication (2.02%), and cell division (0.0%). Unclassified genes constituted the remaining 27.27%. This study reported the results of the first gene expression profile analysis of Chinese native Xiang Pig skeletal muscle cells, thereby greatly facilitating the functional study of candidate genes involved in muscle growth as well as in the improvement of meat quality in domestic pigs.

[Chromosomal mapping of chicken MC4R using a radiation hybrid panel and the comparative analysis of the gene homologous regions between chicken and human chromosome]

Mutations of the melanocortin-4 receptor (MC4R) are associated with hyperphagia, obesity, and accelerated longitudinal growth in pig, mice and human. However, little is known about the functions of this gene in chicken. To map the MC4R gene in Chicken chromosome, we used a 6000 rads chicken-hamster radiation hybrid panel (ChikenRH6). PCR of samples from the ChikenRH6 revealed the location of the MC4R gene to be nearby markers MCW0062, BCL2 and OVY on chromosome 2q12. Five markers were placed into a single linkage group based on two-point analysis with a LOD score of greater than 5. At the same time, the MC4R gene was selected as marker to compare DNA sequence between chicken and human chromosome. The result shows there are the same homologous regions between chicken chromosome 2 (GGA2) and human chromosome 18 (HSA18), and we found that the genes BCL2 and obesity are located in the near regions of MC4R on human chromosome 18. So we can reduce that the chicken MC4R gene maybe there are the same functions with the human MC4R gene. Overall, this work reveals widespread chromosome rearrangements of MC4R between chicken and human genomes, and mappings the chicken MC4R gene on 2q12 by a RH panel.