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1.
Nature ; 569(7758): 703-707, 2019 05.
Artículo en Inglés | MEDLINE | ID: mdl-31022719

RESUMEN

The presence of a quaternary centre-a carbon with four other carbons bonded to it-in any given molecule can have a substantial chemical and biological impact. In many cases, it can enable otherwise challenging chemistry. For example, quaternary centres induce large rate enhancements in cyclization reactions-known as the Thorpe-Ingold effect-which has application in drug delivery for molecules with modest bioavailability1. Similarly, the addition of quaternary centres to a drug candidate can enhance both its activity and its metabolic stability2. When present in chiral ligands3, catalysts4 and auxiliaries5, quaternary centres can guide reactions toward both improved and unique regio-, stereo- and/or enantioselectivity. However, owing to their distinct steric congestion and conformational restriction, the formation of quaternary centres can be achieved reliably by only a few chemical transformations6,7. For particularly challenging cases-for example, the vicinal all-carbon8, oxa- and aza-quaternary centres9 in molecules such as azadirachtin10,11, scopadulcic acid A12,13 and acutumine14-the development of target-specific approaches as well as multiple functional-group and redox manipulations is often necessary. It is therefore desirable to establish alternative ways in which quaternary centres can positively affect and guide synthetic planning. Here we show that if a synthesis is designed such that each quaternary centre is deliberately leveraged to simplify the construction of the next-either through rate acceleration or blocking effects-then highly efficient, scalable and modular syntheses can result. This approach is illustrated using the conidiogenone family of terpenes as a representative case; however, this framework provides a distinct planning logic that is applicable to other targets of similar synthetic complexity that contain multiple quaternary centres.


Asunto(s)
Técnicas de Química Sintética , Terpenos/química , Terpenos/síntesis química , Productos Biológicos/síntesis química , Productos Biológicos/química , Catálisis , Diterpenos/síntesis química , Diterpenos/química , Preparaciones Farmacéuticas/síntesis química , Preparaciones Farmacéuticas/química
2.
BMC Biotechnol ; 24(1): 56, 2024 Aug 12.
Artículo en Inglés | MEDLINE | ID: mdl-39135176

RESUMEN

This study evaluated the effects of supplementing the diet of lactating cows with Acremonium terrestris culture (ATC) on milk production, serum antioxidant capacity, inflammatory indices, and serum lipid metabolomics. Over 90 days, 24 multiparous Chinese Holstein cows in mid-lactation (108 ± 10.4 days in milk, 637 ± 25 kg body weight, 30.23 ± 3.7 kg/d milk yield) were divided into either a control diet (CON) or a diet supplemented with 30 g of ATC daily. All the data were analyzed using Student's t test with SPSS 20.0 software. The results showed that compared with CON feeding, ATC feeding significantly increased milk yield, antioxidant capacity, and immune function. Lipidome screening identified 143 lipid metabolites that differed between the two groups. Further analysis using "random forest" machine learning revealed three glycerophospholipid serum metabolites that could serve as lipid markers with a predictive accuracy of 91.67%. This study suggests that ATC can be a useful dietary supplement for improving lactational performance in dairy cows and provides valuable insights into developing nutritional strategies to maintain metabolic homeostasis in ruminants.


Asunto(s)
Acremonium , Suplementos Dietéticos , Lactancia , Lipidómica , Espectrometría de Masas en Tándem , Animales , Bovinos , Femenino , Lipidómica/métodos , Acremonium/metabolismo , Espectrometría de Masas en Tándem/métodos , Cromatografía Líquida de Alta Presión , Lípidos/sangre , Leche/química , Leche/metabolismo , Alimentación Animal/análisis , Antioxidantes/metabolismo
3.
J Magn Reson Imaging ; 59(3): 1034-1042, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-37272790

RESUMEN

BACKGROUND: The assessment of resectability after neoadjuvant chemotherapy of hepatoblastoma is dependent on Post-Treatment EXTENT of Disease (POSTTEXT) staging and its annotation factors P (portal venous involvement) and V (hepatic venous/inferior vena cava [IVC] involvement), but MR performance in assessing them remains unclear. PURPOSE: To assess the diagnostic performance of contrast-enhanced MR imaging for preoperative POSTTEXT staging and diagnosing vascular involvement in terms of annotation factors P and V in pediatric hepatoblastoma following neoadjuvant chemotherapy. STUDY TYPE: Retrospective. SUBJECTS: Thirty-five consecutive patients (17 males, median age, 24 months; age range, 6-98 months) with proven hepatoblastoma underwent preoperative MR imaging following neoadjuvant chemotherapy. FIELD STRENGTH/SEQUENCE: 3.0 T; T2-weighted imaging (T2WI), T2WI with fat suppression, diffusion weighted imaging, radial stack-of-the-star/Cartesian 3D Dixon T1-weighted gradient echo imaging. ASSESSMENT: Three radiologists independently assessed the POSTTEXT stages and annotation factors P and V based on the 2017 PRE/POSTTEXT system. The sensitivities and specificities were calculated for 1) diagnosing each POSTTEXT stage; 2) discrimination of stages III and IV (advanced) from those stages I and II (non-advanced) hepatoblastomas; and 3) annotation factors P and V. The combination of pathologic findings and surgical records served as the reference standard. STATISTICAL TESTS: Sensitivity, specificity, Fleiss kappa test. RESULTS: The sensitivity and specificity ranges for discriminating advanced from non-advanced hepatoblastomas were 73.3%-80.0% and 80.0%-90.0%, respectively. For annotation factor P, they were 66.7%-100.0% and 90.6%, respectively. For factor V, they were 75.0% and 67.7%-83.9%, respectively. There was excellent, substantial, and moderate agreement on POSTTEXT staging (Fleiss kappa = 0.82), factors P (Fleiss kappa = 0.64), and factors V (Fleiss kappa = 0.60), respectively. DATA CONCLUSION: MR POSTTEXT provides reliable discrimination between advanced and non-advanced tumors, and MR has moderate to excellent specificity at identifying portal venous and hepatic venous/IVC involvement. EVIDENCE LEVEL: 3 TECHNICAL EFFICACY: Stage 3.


Asunto(s)
Hepatoblastoma , Neoplasias Hepáticas , Masculino , Niño , Humanos , Preescolar , Lactante , Hepatoblastoma/tratamiento farmacológico , Hepatoblastoma/patología , Hepatoblastoma/cirugía , Terapia Neoadyuvante , Estudios Retrospectivos , Imagen por Resonancia Magnética/métodos , Venas Hepáticas , Sensibilidad y Especificidad , Neoplasias Hepáticas/patología , Estadificación de Neoplasias
4.
J Enzyme Inhib Med Chem ; 39(1): 2296355, 2024 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-38234133

RESUMEN

Orthosiphon aristatus is a well-known folkloric medicine and herb for Guangdong soup for the treatment of rheumatism in China. Eight isopimarane-type and migrated pimarane-type diterpenoids (1-8), including a new one with a rarely occurring α,ß-unsaturated diketone C-ring, were isolated from O. aristatus. Their structures were determined by spectroscopic methods and quantum chemical calculations. Furthermore, the most abundant compound, orthosiphol K, was structurally modified by modern synthetic techniques to give seven new derivatives (9-15). The anti-rheumatoid arthritis activity of these diterpenoids were evaluated on a TNF-α induced MH7A human rheumatoid fibroblast-like synoviocyte model. Compound 10 showed the most potent activity among these compounds. Based on their inhibitory effects on the release levels of IL-1ß, the preliminary structure-activity relationships were concluded. Furthermore, western blot analysis revealed that 10 could increase the expression of IκBα and decrease the expression of NF-κB p65, and the expression levels of COX-2 and NLRP3 proteins were consequently down-regulated.


Asunto(s)
Artritis Reumatoide , Diterpenos , Orthosiphon , Humanos , Orthosiphon/química , Orthosiphon/metabolismo , Abietanos , Artritis Reumatoide/tratamiento farmacológico , Factor de Necrosis Tumoral alfa , Diterpenos/farmacología , Diterpenos/química , FN-kappa B/metabolismo
5.
J Oral Rehabil ; 2024 Jun 18.
Artículo en Inglés | MEDLINE | ID: mdl-38894533

RESUMEN

BACKGROUND: Painful temporomandibular disorder (TMD) is the common cause of chronic oro-facial pain, which may interfere with sleep. Previous studies have documented an association between sleep and TMD. OBJECTIVES: This study aimed to further explore the association of night-time sleep and daytime napping with painful TMD. METHODS: A total of 419 patients (aged 31.88 ± 11.54 years with women forming 85.4%) from a TMD/Orofacial Pain center were enrolled. Patients' sleep conditions were evaluated with the Pittsburgh Sleep Quality Index (PSQI) questionnaire, and information on night-time sleep duration, napping duration and napping frequency was interviewed. TMD was diagnosed according to the Diagnostic Criteria for TMD protocol and stratified into myalgia (muscle pain), arthralgia (joint pain) and combined (muscle and joint pain) subgroups. The severity of TMD was measured with the Fonseca Anamnestic Index (FAI) questionnaire. Restricted cubic spline (RCS) regression models were established to explore relationships between sleep and painful TMD subgroups. RESULTS: Patients with poor sleep quality (PSQI≥6) had higher FAI scores (median 60, p < .001) and higher proportions of painful TMDs. The myalgia subgroup had higher PSQI scores (median 8, p < .001) than the arthralgia subgroup. The RCS models indicated a non-linear relationship between night-time sleep duration and myalgia (p < .001), which was not observed in arthralgia. However, there were no significant findings concerning napping and painful TMD subgroups. CONCLUSION: This study found that the association between sleep and TMD is mainly related to painful TMD conditions, which are associated with night-time sleep duration.

6.
Chin J Traumatol ; 27(5): 254-262, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-39079771

RESUMEN

PURPOSE: Shaping and assembling contemporary external fixators rapidly for the severe mandibular fractures remains a challenge, especially in emergency circumstance. We designed a novel external fixator that incorporates universal joints to provide the stabilization for mandibular comminuted fractures. This study aims to confirm the efficacy of this novel external fixator through biomechanical tests in vitro and animal experiments. METHODS: In vitro biomechanical tests were conducted using 6 fresh canine with mandibular defect to simulate critical comminuted fractures. Three mandibles were stabilized by the novel external fixator and other mandibles were fixed by 2.5 mm reconstruction plates. All fixed mandibles were subjected to loads of 350 N on the anterior regions of teeth and 550 N on the first molar of the unaffected side. The stability was evaluated based on the maximum displacement and the slope of the load-displacement curve. In animal experiments, 9 beagles with comminuted mandibular fractures were divided into 3 groups, which were treated with the novel external fixation, reconstruction plate, and dental arch bar, respectively. The general observation, the changes in animals' weight, and the surgical duration were recorded and compared among 3 groups. The CT scans were performed at various intervals of 0 day (immediately after the surgery), 3 days, 7 days, 14 days, 21 days, and 28 days to analyze the displacement of feature points on the canine mandible and situation of fracture healing at 28 days. The statistical significance was assessed by the two-way analysis of variance test followed by the Bonferroni test, enabling multiple comparisons for all tests using GraphPad Prism10.1.0 (GraphPad Inc, USA). RESULTS: The outcomes of the biomechanical tests indicated that no statistically significant differences were found in terms of the maximum displacement (p = 0.496, 0.079) and the slope of load displacement curves (p = 0.374, 0.349) under 2 load modes between the external and internal fixation groups. The animal experiment data showed that there were minor displacements of feature points between the external and internal fixation groups without statistic difference, while the arch bar group demonstrated inferior stability. The CT analysis revealed that the best fracture healing happened in the internal fixation group, followed by the external fixation and arch baring at 28 days after fixation. The external fixation group had the shortest fixation duration (25.67 ± 3.79) min compared to internal fixation ((70.67 ± 4.51) min, p < 0.001) and arch baring ((42.00 ± 3.00) min, p = 0.046). CONCLUSION: The conclusion of this study highlighted the efficacy and reliability of this novel external fixator in managing mandibular fractures rapidly, offering a viable option for the initial stabilization of comminuted mandibular fractures in the setting of emergency rescue.


Asunto(s)
Fijadores Externos , Fijación de Fractura , Fracturas Conminutas , Fracturas Mandibulares , Animales , Fracturas Mandibulares/cirugía , Fracturas Mandibulares/diagnóstico por imagen , Fracturas Conminutas/cirugía , Perros , Fijación de Fractura/métodos , Fenómenos Biomecánicos
7.
BMC Oral Health ; 24(1): 397, 2024 Mar 28.
Artículo en Inglés | MEDLINE | ID: mdl-38549071

RESUMEN

OBJECTIVES: This study aimed to summarize the clinical features of non-syndromic late developing supernumerary teeth (LDST) and comparisons with common supernumerary teeth (ST) and explore the association between LDST and the third dentition. MATERIALS AND METHODS: This study retrospected cone-beam computed tomography (CBCT) and medical history of 41,903 consecutive patients from January to December 2021. Comparisons between ST and LDST were evaluated by Chi-square test or Fisher exact test. Correlation between chronological age and dental stage age was evaluated by Spearman's rank correlation coefficient. Binary logistic regression analysis was used to explore the features of LDST originating from the third dentition. RESULTS: Sixty patients with 126 non-syndromic LDST and 1602 patients with 1988 non-syndromic ST were identified. The prevalence of ST and LDST was 3.82% and 0.14%, respectively, with a male-female ratio of 1.78:1 and 1.31:1. LDST patients mainly had LDST in multiple (58.33%) and bilaterally (41.67%), with an average of 2.1/patient. Most LDST were normal-shaped (84.13%), vertically oriented (71.43%), located in the mandible (80.16%), and distributed in the premolar region (82.54%). The study also indicated that the development of LDST was correlated with permanent teeth, with LDST developing 6.48 to 10.45 years later. In this study, 72.22% of LDST met the clinical criteria for the third dentition. CONCLUSIONS: LDST manifested different clinical features from common ST. LDST might be closely related to the third dentition. CLINICAL RELEVANCE: This work would help to comprehend LDST from a clinical perspective, and may be complementary to the criteria of the third dentition.


Asunto(s)
Diente Supernumerario , Humanos , Masculino , Femenino , Diente Supernumerario/diagnóstico por imagen , Diente Supernumerario/epidemiología , Dentición , Dentición Permanente , Diente Premolar , Tomografía Computarizada de Haz Cónico
8.
Metab Eng ; 80: 94-106, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37717646

RESUMEN

An overwhelming number of studies have reported the correlation of decreased abundance of butyrate-producing commensals with a wide range of diseases. However, the molecular-level mechanisms whereby gut butyrate causally affects the host mucosal immunity and pathogenesis were poorly understood, hindered by the lack of efficient tools to control intestinal butyrate. Here we engineered a facultative anaerobic commensal bacterium to delivery butyrate at the intestinal mucosal surface, and implemented it to dissect the causal role of gut butyrate in regulating host intestinal homeostasis in a model of murine chronic colitis. Mechanistically, we show that gut butyrate protected against colitis and preserved intestinal mucosal homeostasis through its inhibiting effect on the key pyroptosis executioner gasdermin D (GSDMD) of colonic epithelium, via functioning as an HDAC3 inhibitor. Overall, our work presents a new avenue to build synthetic living delivery bacteria to decode causal molecules at the host-microbe interface with molecular-level insights.


Asunto(s)
Colitis , Microbioma Gastrointestinal , Animales , Ratones , Butiratos/metabolismo , Interacciones Microbiota-Huesped , Ingeniería Metabólica , Microbioma Gastrointestinal/genética , Bacterias/genética , Bacterias/metabolismo
9.
Chemistry ; 29(45): e202301458, 2023 Aug 10.
Artículo en Inglés | MEDLINE | ID: mdl-37222652

RESUMEN

We present a novel and effective photocatalytic method for the methylation of ß-diketones with controllable degrees of deuterium incorporation via development of new methyl sources. By utilizing a methylamine-water system as the methyl precursor and a cascade assembly strategy for deuteration degree control, we synthesized methylated compounds with varying degrees of deuterium incorporation, showcasing the versatility of this approach. We examined a range of ß-diketone substrates and synthesized key intermediates for drug and bioactive compounds with varying degrees of deuterium incorporation, ranging from 0 to 3. We also investigated and discussed the postulated reaction pathway. This work demonstrates the utility of readily available reagents, methylamines and water, as a new methyl source, and provides a simple and efficient strategy for the synthesis of degree-controllable deuterium-labelled compounds.

10.
BMC Pediatr ; 23(1): 163, 2023 04 06.
Artículo en Inglés | MEDLINE | ID: mdl-37024864

RESUMEN

BACKGROUND: When analyzing the relationship between adenotonsillar hypertrophy and craniofacial morphology, researchers generally regarded hypertrophied adenoids and tonsils as a whole. It remains unclear whether different enlarged sites of pharyngeal lymphoid tissue would correlate with multiple craniofacial subtypes. We hypothesized there would be craniofacial subtypes correlated with different locations of hypertrophied adenoid and tonsil. METHODS: Lateral cephalometric radiographs were obtained from 466 children (171 boys and 295 girls, aged 12.27 ± 2.69 years). They were divided into four groups according to different sites of enlarged pharyngeal lymphoid tissue: adenoid hypertrophy group (AG, n = 126), tonsillar hypertrophy group (TG, n = 59), adenotonsillar hypertrophy group (ATG, n = 69) and control group (CG, n = 212). Five commonly used angles for cephalometric measurements were investigated: SNA (Sella-Nasion-Point A), SNB (Sella-Nasion-Point B), ANB (Point A-Nasion-Point B), mandibular plane angle (MP/SN) and Y-axis angle (SGn/FH). RESULTS: Children with isolated tonsillar hypertrophy correlated with increased SNA (unstandardized regression coefficient B = 1.38, p = 0.009) and SNB (B = 1.99, p = 0.001) compared with controls. However, children with isolated adenoid hypertrophy correlated with decreased SNB (B=-0.94, p = 0.036), increased ANB (B = 0.74, p = 0.014) and increased MP/SN (B = 2.22, p < 0.001). Similarly, children with adenotonsillar hypertrophy correlated with decreased SNB (B=-1.36, p = 0.015), increased ANB (B = 1.35, p < 0.001) and increased MP/SN (B = 2.64, p = 0.001). CONCLUSIONS: Isolated adenoid hypertrophy correlated with a retrognathic mandible, an increased maxillo-mandibular sagittal discrepancy, and an increased mandibular plane angle. Isolated tonsillar hypertrophy correlated with maxillary and mandibular protrusion. Adenotonsillar hypertrophy did not show a superimposed craniofacial pattern of the above two but showed the same craniofacial pattern as isolated adenoid hypertrophy.


Asunto(s)
Tonsila Faríngea , Tonsila Palatina , Masculino , Niño , Femenino , Humanos , Tonsila Palatina/diagnóstico por imagen , Mandíbula , Hipertrofia , Cefalometría
11.
Orthod Craniofac Res ; 26(4): 608-617, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-36919983

RESUMEN

OBJECTIVES: To generate a novel subtype of obstructive sleep apnea (OSA) based on anatomical features and verify the differences in the response of different subtypes to orthodontic treatment, thus providing a theoretical reference for clinical decision-making. MATERIALS AND METHODS: A K-means cluster analysis was performed for this retrospective serial study, which includes 722 OSA patients, aged 44.0 (36.0, 54.0) years, 80.2% male, with apnea-hypopnea index (AHI) of 23.2 (13.4, 39.6) events·h-1 , and body mass index (BMI) of 25.47 ± 3.00 kg·m-2 . All samples were divided into three subtypes based on AHI, BMI, and five variables of craniofacial measurements. Sixty-seven cases with mandibular advancement devices (MAD) therapeutic results were further applied to validate the efficacy and side effects of this treatment in different subtypes. RESULTS: Two hundred and thirty patients (31.9%) were characterized as cluster 1: AHI of 17.65 (11.80, 30.42) events·h-1 , BMI of 23.65 ± 2.62 kg·m-2 , with skeletal Class II high-angle shape. Cluster 2 included 278 patients (38.5%): AHI of 17.00 (11.00, 26.48) events·h-1 , BMI of 25.36 ± 2.53 kg·m-2 , soft palate length (SPL) of 39.25 mm (36.12, 42.20), with basically normal skeleton and normal airway size. Cluster 3, consisting of 214 patients (29.6%), exhibited a combination of anatomical deformity and obesity, with the highest AHI and BMI of 45.35 (30.42, 62.53) events·h-1 and 27.57 ± 2.59 kg·m-2 respectively, but less deformity degree than cluster 1. Cluster 2 had the highest response rate and relatively mild side effects with MAD. CONCLUSIONS: Orthodontic treatment based on anatomical morphology could exert a better effect on mild-moderate OSA patients with mild skeletal deformity.


Asunto(s)
Avance Mandibular , Apnea Obstructiva del Sueño , Humanos , Masculino , Femenino , Estudios Retrospectivos , Polisomnografía/métodos , Apnea Obstructiva del Sueño/terapia , Avance Mandibular/métodos , Análisis por Conglomerados , Fenotipo , Resultado del Tratamiento
12.
Ecotoxicol Environ Saf ; 251: 114527, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-36628874

RESUMEN

The aims of this study were to evaluated the effect and underlying mechanism of Gandankang (GDK) aqueous extract in alleviating the acute liver injury induced by carbon tetrachloride (CCl4) in vivo and in vitro. Mice were divided into 5 groups (n = 8) for acute (Groups: control, 0.3 % CCl4, BD (Bifendate), 1.17, 2.34 and 4.68 mg/kg GDK) liver injury study. 10 µL/g CCl4 with corn oil were injected interperitoneally (i.p) expect the control group. HepG2 cells were used in vitro study. The results showed GDK can effectively inhibit liver damage and restore the structure and function of the liver. In mechanism, GDK inhibited CCl4-induced liver fibrosis and blocked the NF-κB pathway to effectively inhibit the hepatic inflammatory response; and inhibited CCl4-induced oxidative stress by upregulating the Keap1/Nrf2 pathway-related proteins and promoting the synthesis of several antioxidants. Additionally, it inhibited ferroptosis in the liver by regulating the expression of ACSl4 and GPX4. GDK reduced lipid peroxide generation in vitro by downregulating the production of reactive oxygen species and Fe2+ aggregation, thereby inhibiting ferroptosis and alleviating CCl4-induced hepatocyte injury. In conclusion, we describe the potential complex mechanism underlying the effect of GDK against acute liver injury.


Asunto(s)
Tetracloruro de Carbono , Enfermedad Hepática Inducida por Sustancias y Drogas , Ratones , Animales , Tetracloruro de Carbono/toxicidad , Tetracloruro de Carbono/metabolismo , Proteína 1 Asociada A ECH Tipo Kelch/metabolismo , Factor 2 Relacionado con NF-E2/metabolismo , Hígado , Antioxidantes/metabolismo , Estrés Oxidativo , Transducción de Señal , Enfermedad Hepática Inducida por Sustancias y Drogas/metabolismo
13.
Sensors (Basel) ; 23(13)2023 Jun 21.
Artículo en Inglés | MEDLINE | ID: mdl-37447657

RESUMEN

With the increasing demand for remote sensing image applications, extracting the required images from a huge set of remote sensing images has become a hot topic. The previous retrieval methods cannot guarantee the efficiency, accuracy, and interpretability in the retrieval process. Therefore, we propose a bag-of-words association mapping method that can explain the semantic derivation process of remote sensing images. The method constructs associations between low-level features and high-level semantics through visual feature word packets. An improved FP-Growth method is proposed to achieve the construction of strong association rules to semantics. A feedback mechanism is established to improve the accuracy of subsequent retrievals by reducing the semantic probability of incorrect retrieval results. The public datasets AID and NWPU-RESISC45 were used to validate these experiments. The experimental results show that the average accuracies of the two datasets reach 87.5% and 90.8%, which are 22.5% and 20.3% higher than VGG16, and 17.6% and 15.6% higher than ResNet18, respectively. The experimental results were able to validate the effectiveness of our proposed method.


Asunto(s)
Algoritmos , Semántica , Tecnología de Sensores Remotos , Almacenamiento y Recuperación de la Información , Reconocimiento de Normas Patrones Automatizadas/métodos
14.
Angew Chem Int Ed Engl ; 62(31): e202306367, 2023 08 01.
Artículo en Inglés | MEDLINE | ID: mdl-37276015

RESUMEN

Illicium sesquiterpenes are a large family of biologically active secondary metabolites isolated from Illicium species of plants and are well-known for their activity of neurite outgrowth in cultured neurons. Herein, we propose a comprehensive biosynthetic pathway for illicium sesquiterpenes and report a synthetic route to illisimonin A and merrilactone A based on it. We think that the carbon scaffolds of most of the illicium sesquiterpenes could be synthesized from a dicarbonyl derivative of allo-cedrane through retro-Dieckmann condensation, oxidative cleavage and aldol reaction at suitable oxidation states in Nature. The common intermediate for illisimonin A and merrilactone A similar to the dicarbonyl derivative of allo-cedrane was assembled with up to 82 % ee by an asymmetric intramolecular desymmetrizing reductive Heck reaction by the use of a new type of chiral phosphine ligand. The syntheses of illisimonin A and merrilactone A supported the key transformations of the proposed biosynthetic pathway.


Asunto(s)
Illicium , Sesquiterpenos , Neuronas , Lactonas , Estructura Molecular
15.
Angew Chem Int Ed Engl ; 62(15): e202300773, 2023 04 03.
Artículo en Inglés | MEDLINE | ID: mdl-36806846

RESUMEN

Tricrilactones A-H (1-8), a new family of oligomeric 10-membered macrolides featuring collectively five unique ring skeletons, were isolated from a hitherto unexplored fungus, Trichocladium crispatum. Compounds 1 and 7 contain two unconventional bridged (aza)tricyclic core skeletons, 2, 3, 5, and 6 share an undescribed tetracyclic 9/5/6/6 ring system, 4 bears an uncommon 9/5/6/10/3-fused pentacyclic architecture, and 8 is a dimer bridged by an unexpected C-C linkage. Their structures, including absolute configurations, were elucidated by spectroscopic analysis, quantum chemical calculations, and X-ray diffraction analysis. Importantly, the absolute configuration of the highly flexible side chain of 1 was resolved by the asymmetric synthesis of its four stereoisomers. The intermediate-trapping and isotope labeling experiments facilitated the proposal of the biosynthetic pathway for these macrolides. In addition, their antiosteoporosis effects were evaluated in vivo (zebrafish).


Asunto(s)
Chaetomium , Macrólidos , Animales , Estructura Molecular , Macrólidos/química , Pez Cebra , Antibacterianos/farmacología
16.
Fish Shellfish Immunol ; 131: 160-171, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-36210005

RESUMEN

The role of subcutaneous adipose tissue adipocytes and the effects of fatty acids on carrageenan-induced skin inflammation in gilthead seabream (Sparus aurata) were studied. Fish were injected intramuscularly with phosphate-buffered saline (control) or λ-carrageenin (1%), and skin samples collected at the injection site at 3 and 6 h post-injection (p.i.) were processed for histological study. In addition, the presence and levels of lipid classes, fatty acid methyl esters (FAME) and eicosanoids were evaluated in the skin samples obtained from the injected areas. Histological results indicated an increase in adipocyte area in fish sampled at 3 h p.i. with λ-carrageenin compared to fish in the control group. Furthermore, the frequency of adipocytes between 4500 and 5000 µm2 was increased at 6 h in the λ-carrageenin group compared to the control group. Analysis of lipid classes found that fish injected with λ-carrageenan showed increased free fatty acid (FFA) and sphingomyelin content at 3 and 6 h, respectively, compared to the control group. An increase in saturated fatty acids (SFA), n-6 polyunsaturated fatty acids (PUFA), and a decrease in the values of monounsaturated fatty acids (MUFA), n-3 PUFA and minor fatty acids were observed in fish skin at 6 h after λ-carrageenin injection, with respect to the values obtained in the control group. Regarding the analysis of eicosanoids, an increase in hydroxyeicosatetraenoic acid (5-HETE) was detected in the skin of fish at 6 h post-carrageenin injection compared to the control group. The presented results indicate the contribution of adipocytes and fatty acids in the development and regulation of the inflammatory response triggered by λ-carrageenin in gilthead seabream skin.


Asunto(s)
Dorada , Animales , Dorada/fisiología , Ácidos Grasos/análisis , Carragenina , Dieta , Adipocitos , Grasa Subcutánea/química , Inflamación/inducido químicamente , Inflamación/veterinaria
17.
BMC Infect Dis ; 22(1): 651, 2022 Jul 28.
Artículo en Inglés | MEDLINE | ID: mdl-35902828

RESUMEN

BACKGROUND: At present, skeletal tuberculosis (TB) diagnosis is mostly by histopathology, but the positivity rate is low. There is a need to develop new methods for the molecular identification of this disorder. Therefore, we aimed to investigate the clinical utility of quantitative PCR (qPCR)-based diagnosis of skeletal TB from formalin-fixed paraffin-embedded (FFPE) tissues and its comparative evaluation with acid-fast bacillus staining (AFS). METHODS: We detected Mycobacterium tuberculosis (M. tuberculosis/MTB) DNA using qPCR and AFS in FFPE tissue samples from 129 patients suspected of having skeletal TB. The sensitivity, specificity as well as area under the curve (AUC) of qPCR and AFS were calculated. Meanwhile, some factors potentially affecting qPCR and AFS results were investigated. RESULTS: Overall, qPCR outperformed AFS in detecting M. tuberculosis. The AUC of qPCR was higher than that of AFS (0.744 vs.0.561, p < 0.001). Furthermore, decalcification of bone tissues did not affect the sensitivity and specificity of qPCR tests. Whereas it impacted the performance of AFS, decalcification increased AFS's specificity and decreased its sensitivity (p < 0.05). Moreover, qPCR had a significantly larger AUC than AFS in decalcified and non-decalcified groups (0.735/0.756 vs. 0.582/0.534, p < 0.001) respectively. Similarly, the AUC of PCR was more extensive than that of AFS regardless of skeletal TB patients with concomitant pulmonary TB or not (0.929 vs. 0.762; 0.688 vs. 0.524, p < 0.01). CONCLUSIONS: Our data demonstrate that qPCR offers superior accuracy for the detection of mycobacteria in FFPE tissues compared to traditional AFS, indicating its clinical value in osteoarticular TB diagnosis.


Asunto(s)
Mycobacterium tuberculosis , Tuberculosis Ganglionar , Formaldehído , Humanos , Mycobacterium tuberculosis/genética , Adhesión en Parafina , Reacción en Cadena en Tiempo Real de la Polimerasa/métodos , Sensibilidad y Especificidad
18.
Ecotoxicol Environ Saf ; 245: 114118, 2022 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-36174321

RESUMEN

Mori fructus aqueous extracts (MFAEs) have been used as a traditional Chinese medicine for thousands of years with the function of strengthening the liver and tonifying the kidney. However, its inner mechanism to alleviative renal injury is unclear. To investigate the attenuation of MFAEs on nephrotoxicity and uncover its potential molecular mechanism, we established a nephrotoxicity model induced by carbon tetrachloride (CCl4). The mice were randomly divided into control group, CCl4 model group (10% CCl4), CCl4 + low and high MFAEs groups (10% CCl4 + 100 mg/kg and 200 mg/kg MFAEs). We found that MFAEs decreased the kidney index of mice, restored the pathological changes of renal structure induced by CCl4, reduced cystatin C, neutrophil gelatinase-associated lipocalin (NGAL), kidney injury molecule 1 (Kim-1) blood urea nitrogen and creatinine contents in serum, promoted the nuclear transportation of Nrf2 (nuclear factor erythroid derived 2 like 2), elevated the expression of HO-1 (heme oxygenase 1), GPX4 (glutathione peroxidase 4), SLC7A11 (solute carrier family 7 member 11), ZO-1 (zonula occludens-1) and Occludin, suppressed the expression of Keap1 (kelch-like ECH-associated protein 1), HMGB1 (High Mobility Group Protein 1), ACSL4 (acyl-CoA synthetase long chain family member 4) and TXNIP (thioredoxin interacting protein), upregulated the flora of Akkermansia, Anaerotruncus, Clostridium_sensu_stricto, Ihubacter, Alcaligenes, Dysosmobacter, and downregulated the flora of Clostridium_XlVa, Helicobacter, Paramuribaculum. Overlapped with Disbiome database, Clostridium_XlVa, Akkermansia and Anaerotruncus may be the potential genera treated with renal injury. It indicated that MFAEs could ameliorate kidney injury caused by CCl4 via Nrf2 signaling.


Asunto(s)
Microbioma Gastrointestinal , Proteína HMGB1 , Animales , Tetracloruro de Carbono/metabolismo , Tetracloruro de Carbono/toxicidad , Coenzima A/metabolismo , Creatinina , Cistatina C/metabolismo , Proteína HMGB1/metabolismo , Hemo-Oxigenasa 1/metabolismo , Proteína 1 Asociada A ECH Tipo Kelch/metabolismo , Riñón/metabolismo , Ligasas/metabolismo , Lipocalina 2/metabolismo , Ratones , Factor 2 Relacionado con NF-E2/genética , Factor 2 Relacionado con NF-E2/metabolismo , Ocludina/metabolismo , Estrés Oxidativo , Fosfolípido Hidroperóxido Glutatión Peroxidasa , Tiorredoxinas/metabolismo
19.
Ann Plast Surg ; 89(4): 444-450, 2022 10 01.
Artículo en Inglés | MEDLINE | ID: mdl-35703222

RESUMEN

OBJECTIVE: Pedicled perforator partial or complete necrosis with a rate of 13.7%. This study was undertaken to test whether preconditioning with transcutaneous electrical nerve stimulation (TENS) monitored by infrared thermography protect against partial necrosis by converting the choke anastomoses to the true anastomoses via inducing heme oxygenase-1 (HO-1) in a rat pedicled perforator flap model. METHODS: Seventy-two Sprague-Dawley rats were randomly assigned to the control, the TENS, the TENS + SnPP (tin protoporphyrin; HO-1 activity inhibitor; 50 µmol/kg) and the TENS +0.9% saline groups. On the unilateral dorsum of the rats, a rectangular flap donor site of 11 × 3 cm was marked out, which contained three perforator angiosomes and two choke zones. On days 1, 3 and 4, 1 hour of TENS (biphasic pulses, 25 mA, 80 Hz, 200 µs) was applied to the flap donor sites, respectively. On day 5, after the flap donor sites were assessed by infrared thermography, the flaps were harvested based on the deep circumflex iliac artery perforator. RESULTS: Infrared thermography showed that the choke zones in the flap donor sites presented white in the TENS and the TENS +0.9% saline groups, whereas they presented red in the control and the TENS + SnPP groups. Postmortem arteriography showed that the number of arterioles across each choke zone significantly increased in the TENS and the TENS +0.9% saline groups compared with the control and the TENS + SnPP groups. Immunohistochemistry and western blot showed a significant increase in HO-1 in the choke zones after TENS preconditioning. The necrotic area percentage of the flaps was significantly decreased in the TENS (4.3% ± 2.6%) and the TENS +0.9% saline groups (4.5% ± 2.3%) compared with the control (24.8% ± 5.0%) ( P < 0.001); there was no significant difference between the TENS and the TENS + SnPP (24.4% ± 7.3%) groups. CONCLUSIONS: These data show that TENS preconditioning monitored by infrared thermography might be a promising strategy to prevent pedicled perforator flaps from partial necrosis.


Asunto(s)
Colgajo Perforante , Estimulación Eléctrica Transcutánea del Nervio , Animales , Supervivencia de Injerto , Hemo-Oxigenasa 1/farmacología , Metaloporfirinas , Necrosis , Colgajo Perforante/irrigación sanguínea , Protoporfirinas/farmacología , Ratas , Ratas Sprague-Dawley , Solución Salina , Termografía , Estaño/farmacología
20.
Chemistry ; 27(9): 3151-3158, 2021 Feb 10.
Artículo en Inglés | MEDLINE | ID: mdl-33241622

RESUMEN

The development of thermally activated delayed fluorescence (TADF) emitters with orange-red emission still lags behind that of their blue, green, and yellow counterparts. Recent research to address this problem mainly focused on developing new acceptor units. There were few donor units designed especially for orange-red emitters. Herein, with benzothiophene fused to a diphenylacridine donor unit, a new donor moiety, namely, 5,5-diphenyl-5,13-dihydrobenzo[4,5]thieno[3,2-c]acridine (BTDPAc), was designed and synthesized. Benefiting from the strong electron-donating ability of the new donor moiety, a new TADF emitter, 2-[4'-(tert-butyl)(1,1'-biphenyl)-4-yl]-6-[5,5-diphenylbenzo[4,5]thieno[3,2-c]acridin-13(5H)-yl]-1H-benzo[de]isoquinoline-1,3(2H)-dione (BTDPAc-PhNAI), shows an orange-red emission with a maximum at 610 nm in dilute toluene solution. Also, with the help of the diphenyl rings of the donor unit, high photoluminescence quantum yields were achieved for BTDPAc-PhNAI over a wide concentration range. Consequently, an orange-red organic light-emitting diode based on BTDPAc-PhNAI achieved a high external quantum efficiency of nearly 20 %, which was comparable to state-of-the-art device performances with similar emission spectra.

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