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Brown rot of stone fruit, a disease caused by the ascomycete fungus Monilinia fructicola, has caused significant losses to the agricultural industry. In order to explore and discover potential fungicides against M. fructicola, thirty-one novel mandelic acid derivatives containing piperazine moieties were designed and synthesized based on the amide skeleton. Among them, target compound Z31 exhibited obvious in vitro antifungal activity with the EC50 value of 11.8 mg/L, and significant effects for the postharvest pears (79.4 % protective activity and 70.5 % curative activity) at a concentration of 200 mg/L. Antifungal activity for the target compounds was found to be significantly improved by the large steric hindrance of the R1 groups and the electronegative of the piperazines in the molecular structure, according to a three-dimensional quantitative structure-activity relationship (3D-QSAR) analysis. Further mechanism studies have demonstrated that the compound Z31 can disrupt cell membrane integrity, resulting in increased membrane permeability, release of intracellular electrolytes, and affect the normal growth of hyphae. Additional, morphological study also indicated that Z31 may disrupt the integrity of the membrane by inducing generate excess endogenous reactive oxygen species (ROS) and resulting in the peroxidation of cellular lipids, which was further verified by the detection of malondialdehyde (MDA) content. These studies have provided the basis for the creation of novel fungicides to prevent brown rot in stone fruits.
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Tobacco mosaic virus (TMV), as one of the most traditional and extensive biological stresses, poses a serious threat to plant growth and development. In this work, a series of 1-phenyl/tertbutyl-5-amino-4-pyrazole oxadiazole and arylhydrazone derivatives was synthesized. Bioassay evaluation demonstrated that the title compounds (P1-P18) without a "thioether bond" lost their anti-TMV activity, while some of the ring-opening arylhydrazone compounds exhibited superior in vivo activity against TMV in tobacco. The EC50 value of title compound T8 for curative activity was 139 µg/mL, similar to that of ningnanmycin (NNM) (EC50 = 152 µg/mL). Safety analysis revealed that compound T8 had no adverse effects on plant growth or seed germination at a concentration of 250 µg/mL. Morphological observation revealed that compound T8 could restore the leaf tissue of a TMV-stressed host and the leaf stomatal aperture to normal. A mechanism study further revealed that compound T8 not only restored the photosynthetic and growth ability of the damaged host to normal levels but also enhanced catalase (CAT) activity and reduced the content of malondialdehyde (MDA) and hydrogen peroxide (H2O2) in the damaged host, thereby reducing the oxidation damage to the host. TMV-green fluorescent protein (GFP) experiments further demonstrated that compound T8 not only slowed the transmission speed of TMV in the host but also inhibited its reproduction. All of the experimental results demonstrated that compound T8 could reduce the oxidative damage caused by TMV stress and regulate the photosynthetic ability of the host, achieving the ability to repair damage, to make the plant grow normally.
Asunto(s)
Antivirales , Hidrazonas , Nicotiana , Oxadiazoles , Enfermedades de las Plantas , Virus del Mosaico del Tabaco , Virus del Mosaico del Tabaco/efectos de los fármacos , Virus del Mosaico del Tabaco/fisiología , Oxadiazoles/química , Oxadiazoles/farmacología , Hidrazonas/farmacología , Hidrazonas/química , Hidrazonas/síntesis química , Nicotiana/virología , Nicotiana/efectos de los fármacos , Enfermedades de las Plantas/virología , Antivirales/farmacología , Antivirales/síntesis química , Antivirales/química , Diseño de Fármacos , Relación Estructura-Actividad , Hojas de la Planta/química , Hojas de la Planta/efectos de los fármacos , Estructura MolecularRESUMEN
In recent years, the fungal disease 'pepper stem rot', contracted from the soil-borne pathogen sclerotium rolfsii, has been increasing year by year, causing significant losses to the pepper (Capsicum annuum L.) industry. To investigate the infection mechanism of stem rot, the fungus S. rolfsii was used to infect the roots of pepper plants, and was found to affect root morphology and reduce root activity, which subsequently inhibited root growth and development. With fungal infestation, its secretions (oxalic acid, PG and PMG enzyme) were able to break normal tissues in the stem base and induced the burst of the active oxygen, which leads to injury aggravation. Morphological observations of the site of damage at the base of the stem using SEM revealed that the vascular bundles and stomata were completely blocked by hyphae, resulting in a blockade of material exchange in the plant. It was subsequently found that most of the stomata in the leaves were closed, which caused the leaves to lose their ability to photosynthesize, then turned yellow, wilt, shed, and the plant died. Commercialized fungicide thifluzamide with excellent in vitro (EC50 = 0.1 µg/mL) and in vivo curative (EC50 = 29.2 µg/mL) antifungal activity was selected to control the stem rot disease in peppers. The results demonstrated that it was able to suppress the secretion of associated pathogenic factors and reduce the outbursts of reactive oxygen species, thus reducing the damage caused by S. rolfsii at the base of the plant's stem and also enhancing the root activity of the infected plant, thereby promoting root growth. It could also inhibit fungal growth, unblock the vascular bundles and stomata, maintain a balance of material and energy exchange within the plant, and thus restore the damaged plant to its normal growth capacity. All the results will provide an adequate reference for the prevention and control of stem rot disease on peppers with thifluzamide.
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Basidiomycota , Enfermedades de las Plantas , Tiazoles , Enfermedades de las Plantas/prevención & control , Enfermedades de las Plantas/microbiología , AnilidasRESUMEN
The increasing resistance displayed by plant phytopathogenic bacteria to conventional pesticides has heightened the urgency for the exploration of novel antibacterial agents possessing distinct modes of action (MOAs). In this study, a series of novel phenylalanine derivatives with the unique structure of acylhydrazone dithioether have been designed and synthesized. Bioassay results demonstrated that most target compounds exhibited excellent in vitro antibacterial activity against Xanthomonas oryzae pv oryzae (Xoo) and Xanthomonas axonopodis pv citri (Xac). Among them, the EC50 values of L3, L4, L6, L21, and L22 against Xoo were 7.4, 9.3, 6.7, 8.9, and 5.1 µg/mL, respectively, superior to that of bismerthiazol (BT) and thiodiazole copper (TC) (41.5 and >100 µg/mL); the EC50 values of L3, L4, L5, L6, L7, L8, L20, L21, and L22 against Xac were 5.6, 2.5, 6.2, 4.1, 4.2, 6.4, 6.3, 3.6, and 5.2 µg/mL, respectively, superior to that of BT and TC (43.3 and >100 µg/mL). An unmodified drug affinity responsive target stability (DARTS) technology was used to investigate the antibacterial MOAs of active compound L22, and the 50S ribosomal protein L2 (RL2) as an unprecedented target protein in Xoo cells was first discovered. The target protein RL2 was then expressed and purified. Furthermore, the in vitro interactions by microscale thermophoresis (Kd = 0.050 µM) and fluorescence titration (Ka = 1.4 × 105 M-1) experiments also demonstrated a strong binding force between compound L22 and RL2. Overall, these results not only facilitate the development of novel antibacterial agents but also establish a reliable method for exploring the targets of bactericides.
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Oryza , Xanthomonas , Fenilalanina/farmacología , Pruebas de Sensibilidad Microbiana , Oxadiazoles/farmacología , Antibacterianos/química , Oryza/microbiología , Enfermedades de las PlantasRESUMEN
Coronavirus disease 2019 (COVID-19) has become a significant global public health problem. Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2), which causes the disease, utilizes angiotensin-converting enzyme II (ACE2) as a major functional receptor to enter host cells. No study has systematically assessed ACE2 expression in multiple tissues in children. This study investigated ACE2 expression and ACE2 protein's histological distribution in various organs in paediatric patients (the small intestine, thymus, heart and lungs). Our study revealed that ACE2 was highly expressed in enterocytes of the small intestine and widely expressed in the myocardium of heart tissues. The most notable finding was the positive staining of ACE2 in the Hassall's corpuscles epithelial cells. Negligible ACE2 expression in the lung tissues may contribute to a lower risk of infection and fewer symptoms of pneumonia in children than in adults with COVID-19 infection. These findings provide initial evidence for understanding SARS-CoV-2 pathogenesis and prevention strategies in paediatric clinical practice, which should be applicable for all children worldwide.
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COVID-19 , SARS-CoV-2 , Adulto , Humanos , Niño , Enzima Convertidora de Angiotensina 2/genética , Corazón , Salud PúblicaRESUMEN
Plant diseases caused by phytopathogenic fungi are a serious threat in the process of crop production and cause large economic losses to global agriculture. To obtain high-antifungal-activity compounds with novel action mechanisms, a series of 4-substituted mandelic acid derivatives containing a 1,3,4-oxadiazole moiety were designed and synthesized. In vitro bioassay results revealed that some compounds exhibited excellent activity against the tested fungi. Among them, the EC50 values of E13 against Gibberella saubinetii (G. saubinetii), E6 against Verticillium dahlia (V. dahlia), and E18 against Sclerotinia sclerotiorum (S. sclerotiorum) were 20.4, 12.7, and 8.0 mg/L, respectively, which were highly superior to that of the commercialized fungicide mandipropamid. The morphological studies of G. saubinetii with a fluorescence microscope (FM) and scanning electron microscope (SEM) indicated that E13 broke the surface of the hyphae and destroyed cell membrane integrity with increased concentration, thereby inhibiting fungal reproduction. Further cytoplasmic content leakage determination results showed a dramatic increase of the nucleic acid and protein concentrations in mycelia with E13 treatment, which also indicated that the title compound E13 could destroy cell membrane integrity and affect the growth of fungi. These results provide important information for further study of the mechanism of action of mandelic acid derivatives and their structural derivatization.
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Antifúngicos , Fungicidas Industriales , Antifúngicos/química , Fungicidas Industriales/farmacología , Ácidos Mandélicos/farmacología , Oxadiazoles , Relación Estructura-ActividadRESUMEN
PURPOSE: To assess the safety and efficacy of laparoscopic versus open repair of congenital duodenal obstruction (CDO), we conducted a systematic review and meta-analysis (CDO). METHODS: A literature search was conducted to identify studies that compared laparoscopic surgery (LS) and open surgery (OS) for neonates with CDO. Meta-analysis was used to pool and compare variables such as operative time, time to feeding, length of hospital stay, anastomotic leak or stricture, postoperative ileus, wound infection, and overall postoperative complications. RESULTS: Among the 1348 neonatal participants with CDO in the ten studies, 304 received LS and 1044 received OS. When compared to the OS approach, the LS approach resulted in shorter hospital stays, faster time to initial and full feeding, longer operative time, and less wound infection. However, no significant difference in secondary outcomes such as anastomotic leak or stricture, postoperative ileus, and overall postoperative complications was found between LS and OS. CONCLUSIONS: LS is a safe, feasible and effective surgical procedure for neonatal CDO when compared to OS. Compared with OS, LS has a faster time to feeding, a shorter hospital stay, and less wound infection. Furthermore, in terms of anastomotic leak or stricture, postoperative ileus, and overall postoperative complications, LS is equivalent to OS. We conclude that LS should be considered an acceptable option for CDO.
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Obstrucción Duodenal , Ileus , Laparoscopía , Infección de Heridas , Fuga Anastomótica/epidemiología , Constricción Patológica/cirugía , Obstrucción Duodenal/congénito , Humanos , Ileus/cirugía , Recién Nacido , Laparoscopía/métodos , Tiempo de Internación , Complicaciones Posoperatorias/etiología , Estudios Retrospectivos , Resultado del Tratamiento , Infección de Heridas/complicaciones , Infección de Heridas/cirugíaRESUMEN
BACKGROUND: Although thoracoscopic surgery has become the routine surgical method for esophageal atresia/tracheoesophageal fistula (EA/TEF), thoracoscopic treatment for recurrent tracheoesophageal fistula (rTEF) is far from popularized. OBJECTIVES: We aimed to explore the safety and efficacy of thoracoscopic treatment for rTEF with a large-cohort study. METHODS: We retrospectively analyzed the clinical characteristics and outcomes of 103 consecutive patients who underwent thoracoscopic surgery for rTEF by one surgeon after EA/TEF repair at two different institutions in China from 2014 to 2021. RESULTS: One hundred and three pediatric patients (67 boys) were enrolled and the primary operations were performed via thoracoscopic (n = 75, 72.82%) or open surgery (n = 28, 27.18%). The median age at rTEF diagnosis was 5 (3, 10) months after the primary repair. Patients were diagnosed with recurrent fistula to the trachea (n = 97, 94.17%), bronchi (n = 4, 3.88%), and lung parenchyma (n = 2, 1.94%), and all of them underwent thoracoscopic surgery at a median age of 7 (5, 14) months with a median weight of 6200 (4870, 7650) g. After the repair of rTEF, the incidence of esophageal leakage, esophageal stricture, and TEF recurrence were 12.8%, 33.4%, and 10.8%, respectively. After the follow-up, 87 patients survived, 6 died, and 10 were lost to follow-up. CONCLUSIONS: The results of thoracoscopic surgery for rTEF were comparable with previously reported thoracotomy surgery. Owing to the clear field during the operation, rapid patient recovery and esthetic results, the thoracoscopic approach could be a better choice for experienced pediatric surgeons. LEVEL OF EVIDENCE: LEVEL IV.
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Atresia Esofágica , Fístula Traqueoesofágica , Humanos , Niño , Masculino , Lactante , Fístula Traqueoesofágica/etiología , Fístula Traqueoesofágica/cirugía , Atresia Esofágica/cirugía , Estudios Retrospectivos , Estudios de Cohortes , Resultado del Tratamiento , Toracoscopía/efectos adversos , Toracoscopía/métodosRESUMEN
OBJECTIVE: This study aims to investigate and analyze the connection between PITX2 polymorphisms and the susceptibility of congenital esophageal atresia. METHODS: From January 2015 to June 2020, 46 children with congenital esophageal atresia undergoing surgery were recruited for the study and placed in an observation group, and 40 neonates born in pediatrics during the same period were also recruited for the study and placed in a control group. The alleles and distribution frequencies of the polymorphisms of PITX2 gene rs2200733 were analyzed, and the odds ratio (OR) of esophageal atresia caused by the rs2200733 polymorphism were calculated using a logistic analysis. RESULTS: In the observation group, there were 23 patients (50.00%) with the TT genotype of rs2200733, 21 patients with the TC genotype (45.65%), and 2 patients with the CC genotype (4.35%). In the control group, there were 13 patients with the TT genotype (32.50%), 17 patients with the TC genotype (42.50%), and 10 patients with the CC genotype (25.00%), and the differences in the genotypes between the two groups were statistically significant (P<0.05). The frequencies of the T-alleles and C-alleles of rs2200733 in the observation group were 72.83% and 27.17% respectively, while the frequencies of the control group were 53.75% and 46.25% respectively, and the differences in the rs2200733 allele frequencies were statistically significant (P>0.05). Taking the CC genotype as a reference, the neonates with the TC genotype (OR=2.978, 95% CI=1.084~7.952, P=0.042) or the neonates with the TT genotype (OR=4.778, 95% CI=1.208~13.492, P=0.009) had an increased risk of esophageal atresia, of which the TT genotype indicated a higher risk. CONCLUSION: The polymorphic site rs2200733 (T/C) of the PITX2 gene is connected to the incidence of congenital esophageal atresia. The T-allele is a risk factor for congenital esophageal atresia, and compared with the CC genotype, the TT genotype has an increased risk of esophageal atresia.
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Due to its potential adverse effects on human health, perfluorooctanoic acid (PFOA), one of the once widely used legacy per- and polyfluoroalkyl substances (PFASs), has been recently replaced by its novel alternatives including hexafluoropropylene-oxide-dimer-acid (GenX) and ammonium 4,8-dioxa-3H-perfluorononanoate (ADONA). These alternative PFASs are detected in water and exposed workers. PFASs can enter organs like thyroids, however, it is yet unknown whether the new alternatives are safer than PFOA. In the current study, we compared the thyroid disrupting effects of PFOA and its alternatives GenX and ADONA in vitro with both rat thyroid cell line FRTL5 and primary normal human thyroid (NHT) cells. Cells were exposed to ascendant doses of PFOA, GenX or ADONA for various incubation time and cell viability was assessed by WST-1 assay and LDH assay. The proliferation rate of survived cells was determined by crystal violet-based cell proliferation assay and MTT assay. The gene expression of thyroid hormone regulation-related genes in thyroid cells after exposure was quantified by RT-PCR and Western blot. Our data showed that both PFOA and GenX reduced thyroid cell viability in both dose and time dependent manner, with GenX being more toxic than PFOA at the same condition. Similarly, the proliferation rate of cells survived exposure to PFOA and GenX was considerably impaired, with GenX showing more profound adverse effect than PFOA. Unlike PFOA and GenX, ADONA showed no apparent adverse effects on the viability and proliferation of both thyroid cell types. Gene expression data revealed that all three PFASs altered gene expression in both thyroid cells and the altered gene expression seemed to be PFAS and cell type dependent. Taken together, our data reveal that the thyroid disrupting effects is increased in the order of GenX > PFOA > ADONA. Our findings will be beneficial for the guidance of the future usage of PFASs and development of better alternatives.
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Compuestos de Amonio , Fluorocarburos , Adrenocromo/análogos & derivados , Animales , Caprilatos/toxicidad , Fluorocarburos/toxicidad , Óxidos , Compuestos de Amonio Cuaternario , Ratas , Glándula TiroidesRESUMEN
BACKGROUND: With advances in minimally invasive surgery, thoracoscopic repair of oesophageal atresia has become popular in many centres worldwide and indeed has been described as the pinnacle of neonatal surgery. Here, we report our experience in two tertiary referral centres. METHODS: Thoracoscopic technique was introduced in 2007. Thus, a retrospective review of all patients diagnosed with oesophageal atresia was carried out. Patients who had thoracoscopic repair were included, and those who had open repair due to co-morbidities were excluded. Patient demographics, operative data, complications, and associated anomalies were noted. RESULTS: A total of thirty-three patients underwent thoracoscopic repair during the time period. Thirty-one were successfully repaired thoracoscopically. Two patients had conversions due to intra-operative instability. The mean body weight of the neonates was 2.58 kg. The mean operative time was 146 min. Three patients suffered from minor anastomotic leaks, which healed on conservative management. Seven patients had anastomotic strictures, which responded successfully to endoscopic dilatation. Two patients died in the post-operative period due to pneumonia. One patient had a recurrent fistula 3 months after the primary repair, and he subsequently underwent a successful second repair. CONCLUSIONS: In experienced hands, thoracoscopic repair of oesophageal atresia is at least as good as open surgery but with less surgical trauma. Standard of post-operative care contributes significantly to post-operative outcome. Thoracoscopic technique is now our preferred approach.