Background And Objectives: Dual-energy X-ray absorptiometry (DXA) T-scores have been shown to predict fragility fractures in population-based studies. Recently, a novel MRI-based vertebral bone quality (VBQ) score has been proposed, showing better predictability for fragility fractures compared with DXA T-scores. The aim of this study was to explore the correlation between VBQ scores and DXA T-scores and to determine the impact of VBQ scores on the risk of subsequent fragility fractures after cement augmentation for osteoporotic vertebral compression fracture (OVCF).
View Article and Find Full Text PDFThe aza Paternò-Büchi reaction is a [2+2]-cycloaddition reaction between imines and alkenes that produces azetidines, four-membered nitrogen-containing heterocycles. Currently, successful examples rely primarily on either intramolecular variants or cyclic imine equivalents. To unlock the full synthetic potential of aza Paternò-Büchi reactions, it is essential to extend the reaction to acyclic imine equivalents.
View Article and Find Full Text PDFApramycin is a widely used aminoglycoside antibiotic with applications in veterinary medicine. It is composed of a 4-amino-4-deoxy-d-glucose moiety and the pseudodisaccharide aprosamine, which is an adduct of 2-deoxystreptamine and an unusual eight-carbon bicyclic dialdose. Despite its extensive study and relevance to medical practice, the biosynthetic pathway of this complex aminoglycoside nevertheless remains incomplete.
View Article and Find Full Text PDFValanimycin is an azoxy-containing natural product isolated from the fermentation broth of Streptomyces viridifaciens MG456-hF10. While the biosynthesis of valanimycin has been partially characterized, how the azoxy group is constructed remains obscure. Herein, the membrane protein VlmO and the putative hydrazine synthetase ForJ from the formycin biosynthetic pathway are demonstrated to catalyze N-N bond formation converting O-(l-seryl)-isobutyl hydroxylamine into N-(isobutylamino)-l-serine.
View Article and Find Full Text PDFOver-distraction has been shown to be a risk factor for cage subsidence and postoperative neck pain after anterior cervical discectomy and fusion (ACDF). Biomechanical studies have demonstrated increased adjacent segment intradiscal pressure after ACDF. The purpose of this study is to determine if over-distraction of the index disc has an effect on adjacent segment pathology.
View Article and Find Full Text PDFApramycin is an aminoglycoside antibiotic isolated from and that has found clinical use in veterinary medicine. The apramycin structure is notable for its atypical eight-carbon bicyclic dialdose (octose) moiety. While the apramycin biosynthetic gene cluster () has been identified and several of the encoded genes functionally characterized, how the octose core itself is assembled has remained elusive.
View Article and Find Full Text PDFOxsB is a B-dependent radical SAM enzyme that catalyzes the oxidative ring contraction of 2'-deoxyadenosine 5'-phosphate to the dehydrogenated, oxetane containing precursor of oxetanocin A phosphate. AlsB is a homologue of OxsB that participates in a similar reaction during the biosynthesis of albucidin. Herein, OxsB and AlsB are shown to also catalyze radical mediated, stereoselective C2'-methylation of 2'-deoxyadenosine monophosphate.
View Article and Find Full Text PDFOxetanocin A and albucidin are two oxetane natural products. While the biosynthesis of oxetanocin A has been described, less is known about albucidin. In this work, the albucidin biosynthetic gene cluster is identified in Streptomyces.
View Article and Find Full Text PDFStudy Design: A retrospective cohort study.
Objective: To determine radiographic parameters, including the lowest instrumented vertebral (LIV) tilt, related to the postoperative magnitude and progression of residual lumbar curves (LCs) in adolescent idiopathic scoliosis patients who underwent posterior spinal fusion with LIV at or above L1.
Summary Of Background Data: Although several guidelines have been proposed for thoracic curve fusion, factors related to the postoperative magnitude and potential progression of unfused LCs remained undetermined.
Objective: Decreased bone mineral density as measured by dual-energy x-ray absorptiometry (DEXA) has been reported to be associated with cage subsidence following transforaminal lumbar interbody fusion (TLIF). However, DEXA is not often available or routinely performed before surgery. A novel MRI-based vertebral bone quality (VBQ) score has been developed and reported to be correlated with DEXA T-scores.
View Article and Find Full Text PDFPurpose: Artificial intelligence based on deep learning (DL) approaches enables the automatic recognition of anatomic landmarks and subsequent estimation of various spinopelvic parameters. The locations of inflection points (IPs) and apices (APs) in whole-spine lateral radiographs could be mathematically determined by a fully automatic spinal sagittal curvature analysis system.
Methods: We developed a DL model for automatic spinal curvature analysis of whole-spine lateral plain radiographs by using 1800 annotated images of various spinal disease etiologies.
CdSe/CdS with ZnS/ZnO shell quantum dots (QDs) are synthesized by a one-pot method with various oleylamine (OLA) contents. The crystal structures of the QDs were analyzed by X-ray diffractometry, which showed ZnS diffraction peaks. It was represented that the ZnS shell was formed on the surface of the CdSe/CdS core.
View Article and Find Full Text PDFBackground: X-ray is a necessary tool for post-total hip arthroplasty (THA) check-ups; however, parameter measurements are time-consuming. We proposed a deep learning tool, BKNet that automates localization of landmarks with parameter measurements.
Methods: About 3072 radiographs from 3021 patients who underwent THA at our institute between 2013 and 2017 were used.
The structural and functional properties of Osbeck (CGO) seed mucilage by different extraction practices, including conventional citrate buffer, ultrasonic-assisted (UAE), enzymatic-assisted extraction (EAE) with cellulase or Celluclast 1.5 L and various ultrasonic-assisted enzymatic extraction (UAEE) procedures were investigated. It was found that CGO seed from agricultural and processing byproducts is an excellent new source of high methoxyl pectin with quite high intrinsic viscosity (about 108.
View Article and Find Full Text PDFHuman spinal balance assessment relies considerably on sagittal radiographic parameter measurement. Deep learning could be applied for automatic landmark detection and alignment analysis, with mild to moderate standard errors and favourable correlations with manual measurement. In this study, based on 2210 annotated images of various spinal disease aetiologies, we developed deep learning models capable of automatically locating 45 anatomic landmarks and subsequently generating 18 radiographic parameters on a whole-spine lateral radiograph.
View Article and Find Full Text PDFAprD4 is a radical -adenosyl-l-methionine (SAM) enzyme catalyzing C3'-deoxygenation of paromamine to form 4'-oxo-lividamine. It is the only 1,2-diol dehydratase in the radical SAM enzyme superfamily that has been identified and characterized . The AprD4 catalyzed 1,2-diol dehydration is a key step in the biosynthesis of several C3'-deoxy-aminoglycosides.
View Article and Find Full Text PDFWe present an automated method for measuring the sagittal vertical axis (SVA) from lateral radiography of whole spine using a convolutional neural network for keypoint detection (ResUNet) with our improved localization method. The algorithm is robust to various clinical conditions, such as degenerative changes or deformities. The ResUNet was trained and evaluated on 990 standing lateral radiographs taken at Chang Gung Memorial Hospital, Linkou and performs SVA measurement with median absolute error of 1.
View Article and Find Full Text PDFBackground: The optimal anchor density in adolescent idiopathic scoliosis (AIS) surgery to achieve good curve correction remains unclear. The purpose of the study is to analyze the correlations between three-dimensional curve correction and anchor density in the pedicle screw-based posterior fusion of AIS.
Methods: One hundred and twenty-seven AIS patients receiving primary posterior fusion with pedicle screw instrumentation were retrospectively reviewed.
Background: Correcting the scoliosis and stabilizing the spine in the corrected position is the basis of treatment for adolescent idiopathic scoliosis (AIS). Spinal instrumentation and derotation are the principle steps of surgery for any type of AIS. A perspicuous understanding needs to be attained regarding derotation maneuvers in practice; therefore, we intend to compare radiological outcomes following concave and convex rod derotation maneuvers to analyze their efficacy to correct selective Lenke's Type-1 scoliosis.
View Article and Find Full Text PDFThe incorporation of additive in lipid bilayers is one of the ordinary approaches for modulating their properties. Additive effect on phase transition of ion-pair amphiphile (IPA) bilayers, however, is not known. In this work, four double-chained IPAs with different hydrocarbon chain lengths and symmetry were designed and synthesized from single-chained cationic and anionic surfactants by the precipitation method.
View Article and Find Full Text PDFA series of zinc(II) dipicolylamine (ZnDPA)-based drug conjugates have been synthesized to probe the potential of phosphatidylserine (PS) as a new antigen for small molecule drug conjugate (SMDC) development. Using in vitro cytotoxicity and plasma stability studies, PS-binding assay, in vivo pharmacokinetic studies, and maximum tolerated dose profiles, we provided a roadmap and the key parameters required for the development of the ZnDPA based drug conjugate. In particular, conjugate 24 induced tumor regression in the COLO 205 xenograft model and exhibited a more potent antitumor effect with a 70% reduction of cytotoxic payload compared to that of the marketed irinotecan when dosed at the same regimen.
View Article and Find Full Text PDF