Publications by authors named "Yan A Wang"

This study aimed to assess the clinical characteristics, treatment, and prognosis of osteoarticular brucellosis. We conducted a retrospective study enrolling brucellosis patients from the Sixth People's Hospital of Shenyang between September 2014 and June 2019. A total of 1917 participants were admitted during this period.

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2,4-dinitroanisole (DNAN), an insensitive explosive, has replaced trinitrotoluene (TNT) in many melt-cast explosives to improve the safety of ammunition and becomes a promising material to desensitize novel explosives of high sensitivity. Here, we combine thermogravimetric-Fourier transform infrared spectrometry-Mass spectrometry (TG-FTIR-MS), density functional theory (DFT), and ReaxFF molecular dynamics (MD) to investigate its thermal decomposition and detonation mechanisms. As revealed by TG-FTIR-MS, the thermal decomposition of DNAN starts at 453 K when highly active NO is produced and quickly converted to NO resulting in the formation of a large amount of Ph(OH)(OH)OCH.

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Two new styryl lactone derivatives, goniothapic acids A () and B (), and 18 known compounds, were isolated from the twig and leaf extracts of Miq. The structures of new compounds were characterised by spectroscopic methods and HRESITOFMS. Their absolute configuration was established by comparing the experimental and calculated ECD spectra.

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Thorectidiols isolated from the marine sponge (family Thorectidae, order Dictyoceratida) collected in Papua New Guinea are a family of symmetrical and unsymmetrical dimeric biphenyl meroterpenoid stereoisomers presumed to be products of oxidative phenol coupling of a co-occurring racemic monomer, thorectidol (). One member of the family, thorectidiol A (), has been isolated in its natural form, and its structure has been elucidated by analysis of NMR, MS, and ECD data. Acetylation of the sponge extract facilitated isolation of additional thorectidiol diacetate stereoisomers and the isolation of the racemic monomer thorectidol acetate ().

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Serum agglutination test plus exposure history were used to diagnose most cases of human brucellosis in 2 China provinces. After appropriate treatment, 13.3% of acute brucellosis cases progressed to chronic disease; arthritis was an early predictor.

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Breakthrough infection of SARS-CoV-2 is a serious challenge, as increased infections were documented in fully-vaccinated individuals. Recipients with poor antibody response are highly vulnerable to reinfection, whereas those with strong antibody responses achieve sterilizing immunity. Thus far, biomarkers associated with levels of vaccine-elicited antibody response are still lacking.

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Three new indole diterpenoids, aculeatupenes A-C (-), together with four known compounds (-), were isolated from the mycelium of KKU-CT2. Their structures were established by spectroscopic evidence and absolute configurations of - were determined by comparison of their experimental and calculated ECD spectra. Compounds , , and emindole SB () showed weak cytotoxicity against HelaS3, KB, HepG2, MCF-7, and A549 cancer cell lines with IC values in the range of 11.

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In a specifically designed molecular structure, two sp-hybridized carbon atoms align their unhybridized 2p orbitals in the same orientation to form an extremely long C-C σ-single bond that goes beyond 3 Å in length. This new type of C-C σ-bond (coined as a fringe bond) can be made more than 1 Å longer than the current experimental world record (∼1.8 Å) and 300 kJ/mol weaker than the ordinary C-C σ-bond (∼330 kJ/mol).

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Five new compounds-two phloroglucinol benzophenones, garciniacowones F () and G (), and three xanthones, garciniacowones H (), I (), and J ()-together with seven known xanthones (-) were isolated from the fresh leaves of . Their structures were elucidated by detailed analysis of NMR and MS data. Compounds and are phloroglucinol benzophenones containing a polyprenylated bicyclo[3.

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After carefully analyzing the Kamlet-Jacobs (K-J) equations and the structural traits of well-known explosives, hexahydro-1,3,5-trinitro-1,3,5-triazin (RDX), octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine (HMX), and hexanitrohexaazaisowurtizitane (CL-20), diverse nitramine explosives including linear (Models IA, IB, and IC), cyclic (Model II), and caged (Models IIIA and IIIB) molecules were designed by incorporating various number () of -CHNNO- structural unit and studied using the B3LYP/6-31G* and B3PW91/6-31G** methods of the density functional theory. Computational results show that all of the energetic parameters, that is, density (ρ), detonation velocity (), and detonation pressure (), follow the order of IIIB > IIIA > II > IA > IB > IC. With the increasing , the and of linear nitramines eventually keep stable.

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Syn and anti dihydropyrene (DHP) are excellent thermochromes, and therefore extensively studied for their thermochromic and photochromic properties, respectively. However, they suffer from thermal decomposition due to thermal instability. In this study, we thoroughly investigated pathways for the thermal decomposition of anti- and syn- dihydropyrenes through computational methods.

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Four new chalcones (1, 10, 13, and 14), a new flavanone, (9), a new amide (8), and 19 known compounds were acquired from Melodorum siamensis. The structures were established by NMR and MS data analyses. Compounds 1 (er 1.

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Infantile hemangiomas (IHs) are the most common vascular tumors of infancy. Oral propranolol has achieved great success in treating IHs since 2008. To minimize the systemic side events caused by oral administration of propranolol, topical timolol started to be applied in the treatment of IHs, especially for superficial lesions.

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Biotransformation of β-mangostin (1) by the endophytic fungus Xylaria feejeensis GM06 afforded hexacyclic ring-fused xanthenes with an unprecedented hexacyclic heterocylic skeleton. β-Mangostin (1) was transformed to two diastereomeric pairs of enantiomers, mangostafeejin A [(-)-2a/(+)-2b)] and mangostafeejin B [(-)-3a/(+)-3b)]. The chemical structures of the transformation products were elucidated by analysis of NMR and MS data, and the structure of mangostafeejin A [(-)-2a/(+)-2b)] was confirmed by single-crystal X-ray diffraction analysis.

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Kaposiform hemangioendothelioma (KHE) is a relatively rare vascular tumor with an aggressive and infiltrating nature. Previous studies have revealed an exclusive relationship between KHE and Kasabach-Merritt Phenomenon (KMP), which is associated with high morbidity and mortality. No universally accepted treatment modality exists for refractory KHE with or without KMP.

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Treatment of microcystic lymphatic malformations (LMs) is still a great challenge to physicians in the field of managing vascular anomalies. Several kinds of treatment have been proposed for microcystic LMs, but the responses to these treatment modalities vary considerably among individuals. The aim of the study was to investigate the safety and efficacy of intralesional injection of pingyangmycin for microcystic LMs located in the deep facial region.

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A two-dimensional potential energy surface was utilized to treat the proton transfer in acetylacetone (AA) and its α-halo derivatives: α-fluoro-(FAA), α-chloro-(ClAA), and α-bromo-acetylacetone (BrAA). This potential energy function, which couples O-H stretching and in-plane bending vibrations, was acquired through ab initio calculations for a fixed skeleton geometry. The resulting potential energy surfaces were then used to calculate the proton tunneling frequencies and proton transfer barrier heights.

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Arteriovenous malformations (AVMs) are congenital vascular malformations (CVMs) resulting from birth defects of the vasculature. It is rarely seen, only accounting for 1.5% of all vascular anomalies, and 50% of the lesions are located in the oral and maxillofacial region.

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Extracts of laboratory cultures of the fungus Penicilium purpurogenum obtained from rotting fruit of the tree Averrhoa bilimbi growing in Sri Lanka have yielded 10 new meroterpenoids, dhilirolides E-N (5-14). The structures of the new dhilirolides have been elucidated by analysis of spectroscopic data and a single-crystal X-ray diffraction analysis of dhilirolide L (12). Dhilirolides A-N (1-14) represent the four unprecedented and rearranged dhilirane, isodhilirane, 14,15-dinordhilirane, and 23,24-dinorisodhilirane meroterpenoid carbon skeletons.

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Tricholemmal carcinoma is an extremely rare malignancy of the skin, and its biological behavior and management is controversial. The objective of the present study was to investigate the clinicopathological characteristics and management of tricholemmal carcinoma of the head and neck region. The study analyzed 15 patients with tricholemmal carcinoma.

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Computational methods were used to study the experimental finding that forming decamethyldizincocene is more efficient when using a reducing agent (e.g., KH) and ZnCl2 as opposed to a sole ZnR2 reagant.

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Infantile hemangiomas are the most common benign vascular tumors in infancy and childhood. As hemangioma could regress spontaneously, it generally does not require treatment unless proliferation interferes with normal function or gives rise to risk of serious disfigurement and complications unlikely to resolve without treatment. Various methods for treating infant hemangiomas have been documented, including wait and see policy, laser therapy, drug therapy, sclerotherapy, radiotherapy, surgery and so on, but none of these therapies can be used for all hemangiomas.

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Four new sesterterpenoids, ansellone B (4), phorbadione (5), secoepoxyansellone A (6), and alotaketal C (7), have been isolated from specimens of the sponge Phorbas sp. collected in British Columbia. Ansellone B (4) has an unprecedented heterocyclic skeleton featuring an oxocane ring, and secoepoxyansellone A (6) is the first example of the degraded "secoansellane" sesterterpenoid carbon skeleton.

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Venous malformation is one of the most common benign vascular lesions, with approximately 40% of cases appearing in the head and neck. They can affect a patient's appearance and functionality and even cause life-threatening bleeding or respiratory tract obstruction. The current methods of treatment include surgery, laser therapy, sclerotherapy, or a combined.

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Computational methods were used to study the surprising 2004 synthesis of decamethyldizincocene, Zn2(η(5)-C5Me5)2, which was the first molecule to have a direct, unbridged bond between two first-row transition metals. The computational results show that the methyl groups of decamethylzincocene, Zn(η(5)-C5Me5)(η(1)-C5Me5), affect the transition-state stability of its reaction with ZnEt2 (or ZnPh2) through steric hindrance, and this could possibly allow a counter-reaction, the homolytic dissociation of Zn(η(5)-C5Me5)(η(1)-C5Me5) into Zn(η(5)-C5Me5)(•) and (η(1)-C5Me5)(•), to occur, and because no such steric hindrance occurs when zincocene, Zn(η(5)-C5H5)(η(1)-C5H5), is used as a reactant, its dissociation never occurs regardless of what ZnR2 reagent is used.

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